bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Gamma Radiation on Resonant and Antiresonant Characteristics of Piezoelectric Wafer Active Sensors
Authors: Haider Mohammad Faisal , Giurgiutiu Victor , Lin Bin , Yu Lingyu , Lam Poh-Sang , Verst Christopher
Published: August 2018

This paper presents gamma radiation effects on resonant and antiresonant characteristics of piezoelectric wafer active sensors (PWAS) for structural health monitoring (SHM) applications to nuclear-spent fuel storage facilities. The irradiation test was done in a Co-60 gamma irradiator. Lead zirconate titanate (PZT) and Gallium Orthophosphate (GaPO4) PWAS transducers were exposed to 225 kGy gamma radiation dose. First, 2 kGy of total radiation dose was achieved with slower radiation rate at 0.1 kGy/h for 20; h then the remaining radiation dose was achieved with accelerated radiation rate at 1.233 kGy/h for 192 h. The total cumulative radiation dose of 225 kGy is equivalent to 256 years of operation in nuclear-spent fuel storage facilities. Electro-mechanical impedance and admittance (EMIA) signatures were measured after each gamma radiation exposure. Radiation-dependent logarithmic sensitivity of PZT-PWAS in-plane and thickness modes resonance frequency (∂(fR)/∂( logeRd)) was estimated as 0.244 kHz and 7.44 kHz, respectively; the logarithmic sensitivity of GaPO4-PWAS in-plane and thickness modes resonance frequency was estimated as 0.0629 kHz and 2.454 kHz, respectively. Therefore, GaPO4-PWAS EMIA spectra show more gamma radiation endurance than PZT-PWAS. Scanning electron microscope (SEM) and X-ray diffraction method (XRD) was used to investigate the microstructure and crystal structure of PWAS transducers. From SEM and XRD results, it can be inferred that there is no significant variation in the morphology, the crystal structure, and grain size before and after the irradiation exposure.
Probabilistic Analysis of Extreme Riser Responses for a Weather-Vaning FPSO in Tropical Cyclones
Authors: Armstrong Curtis , Drobyshevksi Yuriy , Chin Christopher , Penesis Irene
Published: August 2018

The probability distributions of extreme responses of a flexible riser connected to a weather-vaning floating production storage and offloading (FPSO) are developed and investigated numerically for two tropical cyclones. Statistical properties of riser responses provide the foundation for response based analysis (RBA), a comprehensive approach for the prediction of extreme responses and design metocean conditions of offshore systems. The storm-based probabilistic analysis is applied to responses of flexible risers with the objective to develop their distributions in a storm and to determine their most probable maximum (MPM) values. An asymptotic form of the response distribution in a storm is formulated, which can be used in the random event, method of Tromans and Vandersohuren (1995, “Response Based Design Conditions in the North Sea: Application of a New Method,” Offshore Technology Conference, Houston, TX, May 1–4). The methodology is illustrated by two case studies for an FPSO in cyclonic storms at a location offshore Australia. Time domain simulations are employed to predict the FPSO motions, critical riser responses, and their probability distributions. It is shown that the maximum storm responses can be reproduced by governing “equivalent” metocean intervals with increased percentiles or inflated durations. Effects of different environmental excitation upon the risers and their impact on the statistical properties of responses are discussed, providing important insights for extension toward a multistorm RBA approach. The study also discusses issues with practices such as the analysis for a 3 h design event and presents observations on the variability of several types of responses, which reveal their environmental sensitivities.
Effects of Uncertainty and Quasi-Chaotic Geometry on the Leakage of Brush Seals
Authors: Fuchs Alexander , Haidn Oskar J.
Published: August 2018

This article presents a brief review of the experimental and theoretical state of the art regarding the leakage flow prediction of brush seals. The authors model a computational fluid dynamics (CFD)-based approach for the leakage flow of brush seals. The brush seal is treated by modeling its real geometrical structure, namely numerous bristles in an array in transverse flow. The fluid domain is segregated into discrete volumes surrounding each bristle. Two different discretization schemes are chosen to study their influence on the leakage behavior. Furthermore, for each scheme multiple inter-bristle distances, pressure ratios and turbulence models are evaluated. In addition, the influence of irregular arrangement configurations, which forms a quasi-chaotic inner structure, is studied. The results gained are compared to other authors' experimental and numerical data.
Hydrodynamic Flow Characteristics in an Internally Circulating Fluidized Bed Gasifier
Authors: Simanjuntak J. P. , Al-attab K. A. , Zainal Z. A.
Published: August 2018

In this paper, the hydrodynamic flow inside an internally circulating fluidized bed (ICFBG) was characterized using experimental and three-dimensional computational fluid dynamics (CFD) models. Eulerian-Eulerian model (EEM) incorporating the kinetic theory of granular flow was implemented in order to simulate the gas–solid flow. A full-scale plexiglass cold flow experimental model was built to verify simulation results prior to the fabrication of the gasifier. Six parameters were manipulated to achieve the optimum design geometry: fluidization flow rate of the draft tube (Qdt), aeration flow rate of the annulus (Qan), initial bed static height (Hbs), draft tube height (Hdt), draft tube diameter (Ddt), and orifice diameter (Dor). The investigated parameters showed strong effect on the particle flow characteristics in terms of the pressure difference (ΔP) and solid circulation rate (Gs). The predicted results by simulation for the optimum case were in close agreement with experimental measurements with about 5% deviation. The results show that the ICFBG operated stably with the maximum Gs value of 86.6 kg/h at Qdt of 350 LPM, Qan of 150 LPM, Hbs of 280 mm, Hdt of 320 mm, Ddt of 100 mm, and Dor of 20 mm.
Mobilization of Crude Oil in Porous Media With Oil-Soluble Surfactant Delivered by Hydrosoluble Micelles
Authors: Ezeh Chike G. , Duan Yufei , Rausa Riccardo , Papadopoulos Kyriakos D.
Published: August 2018

In this work, an oil-soluble surfactant was studied to enhance crude oil mobilization in a cryolite-packed miniature bed. The cryolite packed bed provided a transparent, random porous medium for observation at the microscopic level. In the first part of the paper, oil-soluble surfactants, Span 80 and Eni-surfactant (ES), were dissolved directly into the crude oil. The porous medium was imbued with the crude oil (containing the surfactants), and de-ionized water was the flooding phase; in this experiment, the system containing ES had the best performance. Subsequently, sodium dodecyl sulfate (SDS), a hydrosoluble surfactant, was used to solubilize the ES, with the SDS acting as a carrier for the ES to the contaminated porous media. Finally, the SDS/ES micellar solutions were used in oil-removal tests on the packed bed. Grayscale image analysis was used to quantify the oil recovery effectiveness for the flooding experiments by measuring the white pixel percentage in the packed bed images. The SDS/ES flooding mixture had a better performance than the SDS alone.
A Comprehensive Review of Thermal Enhanced Oil Recovery: Techniques Evaluation
Authors: Mokheimer Esmail M. A. , Hamdy M. , Abubakar Zubairu , Shakeel Mohammad Raghib , Habib Mohamed A. , Mahmoud Mohamed
Published: August 2018

The oil production from any well passes through three stages. The first stage is the natural extraction of oil under the well pressure, the second stage starts when the well pressure decreases. This second stage includes flooding the well with water via pumping sea or brackish water to increase the well pressure and push the oil up enhancing the oil recovery. After the first and secondary stages of oil production from the well, 20–30% of the well reserve is extracted. The well is said to be depleted while more than 70% of the oil are left over. At this stage, the third stage starts and it is called the enhanced oil recovery (EOR) or tertiary recovery. Enhanced oil recovery is a technology deployed to recover most of our finite crude oil deposit. With constant increase in energy demands, EOR will go a long way in extracting crude oil reserve while achieving huge economic benefits. EOR involves thermal and/or nonthermal means of changing the properties of crude oil in reservoirs, such as density and viscosity that ensures improved oil displacement in the reservoir and consequently better recovery. Thermal EOR, which is the focus of this paper, is considered the dominant technique among all different methods of EOR. In this paper, we present a brief overview of EOR classification in terms of thermal and nonthermal methods. Furthermore, a comprehensive review of different thermal EOR methods is presented and discussed.
Optimal Pitch Control Design With Disturbance Rejection for the Controls Advanced Research Turbine
Authors: Wenzhong Gao David , Wang Xiao , Wang Jianhui , Gao Tianqi , Stefanovic Margareta , Li Xiangjun
Published: August 2018

Advanced and model-based control techniques have become prevalent in modern wind turbine controls in the past decade. These methods are more attractive compared to the commonly used proportional-integral-derivative (PID) controller, as the turbine structural flexibility is increased with multiple and coupled modes. The disturbance accommodating control (DAC) is an effective turbine control approach for the above-rated wind speed region. DAC augments the turbine state-space model with a predefined disturbance waveform model, based on which the controller reduces the impact of wind disturbances on the system output (e.g., rotor speed). However, DAC cannot completely reject the wind disturbance in certain situations, and this results in steady-state regulation errors in the turbine rotor speed and electric power. In this paper, we propose a novel wind turbine pitch control using optimal control theory. The obtained feedback and feedforward control terms function to stabilize the turbine system and reject wind disturbances, respectively, derived systematically based on the Hamilton–Jacobi–Bellman (HJB) equation. Simulation results show that the proposed method achieves desired rotor speed regulation with significantly reduced steady-state errors under turbulent winds, which is simulated on the model of the three-bladed controls advanced research turbine (CART3) using the FAST code.
On-Sun Performance Evaluation of Alternative High-Temperature Falling Particle Receiver Designs
Authors: Ho Clifford K. , Christian Joshua M. , E. Yellowhair Julius , Armijo Kenneth , Kolb William J. , Jeter Sheldon , Golob Matthew , Nguyen Clayton
Published: August 2018

This paper evaluates the on-sun performance of a 1 MW falling particle receiver. Two particle receiver designs were investigated: obstructed flow particle receiver versus free-falling particle receiver. The intent of the tests was to investigate the impact of particle mass flow rate, irradiance, and particle temperature on the particle temperature rise and thermal efficiency of the receiver for each design. Results indicate that the obstructed flow design increased the residence time of the particles in the concentrated flux, thereby increasing the particle temperature and thermal efficiency for a given mass flow rate. The obstructions, a staggered array of chevron-shaped mesh structures, also provided more stability to the falling particles, which were prone to instabilities caused by convective currents in the free-fall design. Challenges encountered during the tests included nonuniform mass flow rates, wind impacts, and oxidation/deterioration of the mesh structures. Alternative materials, designs, and methods are presented to overcome these challenges.
Comparative Performance of a Solar Screen With Respect to Perforation Ratio: Illuminance and Energy Saving
Authors: Alawadhi Esam M.
Published: August 2018

The objectives of sustainable building design are to provide the comfort to the occupants and to eliminate negative environmental impacts of its operations. In this regard, windows play a crucial role in saving energy used for electrical lights and enhancing the indoor visual environment. Excessive sunlight penetration through the windows could increase the heat gains and create the uncomfortable visual environment. Hence, external shading devices, such as solar screens, control the sunlight penetration and minimize its negative effects. The objectives of this research are to provide new insight into the impact of installing the solar screen on the indoor visual environment and heat gain through the window. Experimental measurements are conducted in extreme weather month and window direction, in June and for West facing façade window. Three design patterns of the solar screen were considered with perforation ratios of 12.5%, 25%, and 35%. Without a solar screen, the results show that there is a significant illuminance level variation in the indoor space, between 200 and 2250 Lux. However, if a solar screen with 12.5% perforation ratio is installed, the illuminance level in entire indoor space becomes uniform, it is maintained at 400 Lux during the daytime, and thereby visual comfort is attained. Additionally, the heat gain through the window is decreased by 52.8%, and the window is prevented from heating up during the daytime.
Development of perception and perceptual learning for multi-timescale filtered speech
Authors: Huyck Julia Jones , Rosen Merri J.
Published: August 2018

The perception of temporally changing auditory signals has a gradual developmental trajectory. Speech is a time-varying signal, and slow changes in speech (filtered at 0–4 Hz) are preferentially processed by the right hemisphere, while the left extracts faster changes (filtered at 22–40 Hz). This work examined the ability of 8- to 19-year-olds to both perceive and learn to perceive filtered speech presented diotically for each filter type (low vs high) and dichotically for preferred or non-preferred laterality. Across conditions, performance improved with increasing age, indicating that the ability to perceive filtered speech continues to develop into adolescence. Across age, performance was best when both bands were presented dichotically, but with no benefit for presentation to the preferred hemisphere. Listeners thus integrated slow and fast transitions between the two ears, benefitting from more signal information, but not in a hemisphere-specific manner. After accounting for potential ceiling effects, learning was greatest when both bands were presented dichotically. These results do not support the idea that cochlear implants could be improved by providing differentially filtered information to each ear. Listeners who started with poorer performance learned more, a factor which could contribute to the positive cochlear implant outcomes typically seen in younger children.
Effects of vowel context and discriminability on band independence in nonsense syllable recognition
Authors: Whitmal Nathaniel A.
Published: August 2018

The Speech Intelligibility Index algorithm [(1997). ANSI S3.5-1997] models cues in disjoint frequency bands for consonants and vowels as additive, independent contributions to intelligibility. Data from other studies examining only consonants in single-vowel nonsense stimuli exhibit synergetic and redundant band contributions that challenge the band independence assumption. The present study tested the hypotheses that (a) band independence is present for multi-vowel stimuli, and (b) dependent band contributions are artifacts of confounding stimulus administration and testing methods. Data were measured in two experiments in which subjects identified filtered nonsense consonant-vowel-consonant syllables using a variety of randomly selected vowels. The measured data were used in simulations that further characterized the range of subject responses. Results of testing and simulation suggest that, where present, band independence is fostered by low broadband error, high vowel diversity, and high vowel discriminability. Synergistic band contributions were observed for confusable vowels that were most susceptible to filtering; redundant contributions were observed for the least susceptible vowels. Implications for intelligibility prediction and enhancement are discussed.
Sociodemographic and psychological determinants of influenza vaccine intention among recipients of autologous and allogeneic haematopoietic stem cell transplant: a cross-sectional survey of UK transplant recipients using a modified health belief model
Authors: Miller Paul D E , Forster Alice S , de Silva Thushan I , Leonard Hayley , Anthias Chloe , Mayhew Michaela , Klammer Matthias , Paskar Susan , Hurst Erin , Peggs Karl , Madrigal Alejandro , A Snowden John
Published: August 2018

Objectives

Studies exploring vaccination rates among haematopoietic stem cell transplant (HSCT) recipients have focused on physician factors that limit uptake. Understanding the patient factors that determine vaccination intention is crucial to delivering a successful vaccination programme. Using a modified health belief model (mHBM), we conducted a cross-sectional survey with the objective of exploring the sociodemographic and psychological factors that determined autologous and allogeneic HSCT recipients’ intention to receive the seasonal inactivated influenza vaccine (SIIV) during the 2015–2016 influenza season.

Setting

The setting of our study was three tertiary level, UK National Health Service (NHS) autologous and allogeneic HSCT centres.

Participants

Eligible patients were aged 16 years or over and recipients of autologous or allogeneic HSCT for any disease indication, with no absolute contraindication to receiving the SIIV during the next influenza season, and having not received the SIIV since transplant. 93 participants from 3 UK NHS HSCT centres completed an anonymous study-specific questionnaire. 78.5% were recipients of allogeneic and 21.5% autologous HSCT.

Results

23.7% of participants expressed low intent to receive the SIIV. Patients aged over 65 (OR 0.02, 95% CI 0.01 to 0.57, p=0.02) and those who had not received the SIIV prior to HSCT (OR 0.04, 95% CI 0.02 to 0.56, p=0.02) were less likely to have high intent. A multivariate logistic regression model incorporating constructs of the mHBM was statistically significant (p<0.001) and explained 74.7% of variation in SIIV intention. More patients felt that a recommendation from their HSCT team than their general practitioner would prompt them to receive the SIIV, and this was most pronounced in those who had low intent.

Conclusions

The mHBM may provide a useful structure for addressing low vaccine intent among HSCT recipients and further interventional studies are warranted. We would encourage HSCT and general practitioners to discuss SIIV intention as a routine part of care.
Ethnic differences in frailty: a cross-sectional study of pooled data from community-dwelling older persons in the Netherlands
Authors: Franse Carmen Betsy , van Grieken Amy , Qin Li , Melis Rene J F , Rietjens Judith A C , Raat Hein
Published: August 2018

Objective

Few European studies examined frailty among older persons from diverse ethnic backgrounds. We aimed to examine the association of ethnic background with frailty. In addition, we explored the association of ethnic background with distinct components that are considered to be relevant for frailty.

Design and setting

This was a cross-sectional study of pooled data of The Older Persons and Informal Caregivers Survey Minimum DataSet (TOPICS) in the Netherlands.

Participants

Community-dwelling persons aged 55 years and older with a Dutch, Indonesian, Surinamese, Moroccan or Turkish ethnic background were included (n=23 371).

Measurements

Frailty was assessed with the validated TOPICS-Frailty Index that consisted of 45 items. The TOPICS-Frailty Index contained six components: morbidities, limitations in activities of daily living (ADL), limitations in instrumental ADL, health-related quality of life, psychosocial health and self-rated health. To examine the associations of ethnic background with frailty and with distinct frailty components, we estimated multilevel random-intercept models adjusted for confounders.

Results

TOPICS-Frailty Index scores varied from 0.19 (SD=0.12) among persons with a Dutch background to 0.29 (SD=0.15) in persons with a Turkish background. After adjustment for age, sex, living arrangement and education level, persons with a Turkish, Moroccan or Surinamese background were frailer compared with persons with a Dutch background (p<0.001). There were no significant differences in frailty between persons with an Indonesian compared with a Dutch background. The IADL component scores were higher among all groups with a non-Dutch background compared with persons with a Dutch background (p<0.05 or lower for all groups).

Conclusions

Compared with older persons with a Dutch background, persons with a Surinamese, Moroccan or Turkish ethnic background were frailer. Targeted intervention strategies should be developed for the prevention and reduction of frailty among these older immigrants.
Interventions to improve patient flow in emergency departments: an umbrella review
Authors: De Freitas Loren , Goodacre Steve , O’Hara Rachel , Thokala Praveen , Hariharan Seetharaman
Published: August 2018

Objectives

Patient flow and crowding are two major issues in ED service improvement. A substantial amount of literature exists on the interventions to improve patient flow and crowding, making it difficult for policymakers, managers and clinicians to be familiar with all the available literature and identify which interventions are supported by the evidence. This umbrella review provides a comprehensive analysis of the evidence from existing quantitative systematic reviews on the interventions that improve patient flow in EDs.

Methods

An umbrella review of systematic reviews published between 2000 and 2017 was undertaken. Included studies were systematic reviews and meta-analyses of quantitative primary studies assessing an intervention that aimed to improve ED throughput.

Results

The search strategy yielded 623 articles of which 13 were included in the umbrella review. The publication dates of the systematic reviews ranged from 2006 to 2016. The 13 systematic reviews evaluated 26 interventions: full capacity protocols, computerised provider order entry, scribes, streaming, fast track and triage. Interventions with similar characteristics were grouped together to produce the following categories: diagnostic services, assessment/short stay units, nurse-directed interventions, physician-directed interventions, administrative/organisational and miscellaneous. The statistical evidence from 14 primary randomised controlled trials (RCTs) was evaluated to determine if correlation or clustering of observations was considered. Only the fast track intervention had moderate evidence to support its use but the RCTs that assessed the intervention did not use statistical tests that considered correlation.

Conclusions

Overall, the evidence supporting the interventions to improve patient flow is weak. Only the fast track intervention had moderate evidence to support its use but correlation/clustering was not taken into consideration in the RCTs examining the intervention. Failure to consider the correlation of the data in the primary studies could result in erroneous conclusions of effectiveness.
Emergency department provider perspectives on elder abuse and development of a novel ED-based multidisciplinary intervention team
Authors: Rosen Tony , Stern Michael E , Mulcare Mary R , Elman Alyssa , McCarthy Thomas J , LoFaso Veronica M , Bloemen Elizabeth M , Clark Sunday , Sharma Rahul , Breckman Risa , Lachs Mark S
Published: August 2018

Background

An ED visit provides a unique opportunity to identify elder abuse, which is common and has serious medical consequences. Despite this, emergency providers rarely recognise or report it. We have begun the design of an ED-based multidisciplinary consultation service to improve identification and provide comprehensive medical and forensic assessment and treatment for potential victims.

Methods

We qualitatively explored provider perspectives to inform intervention development. We conducted 15 semistructured focus groups with 101 providers, including emergency physicians, social workers, nurses, technologists, security, radiologists and psychiatrists at a large, urban academic medical centre. Focus groups were transcribed, and data were analysed to identify themes.

Results

Providers reported not routinely assessing for elder mistreatment and believed that they commonly missed it. They reported 10 reasons for this, including lack of knowledge or training, no time to conduct an evaluation, concern that identifying elder abuse would lead to additional work, and absence of a standardised response. Providers believed an ED-based consultation service would be frequently used and would increase identification, improve care and help ensure safety. They made 21 recommendations for a multidisciplinary team, including the importance of 24/7 availability, the value of a positive attitude in a consulting service and the importance of feedback to referring ED providers. Participants also highlighted that geriatric nurse practitioners may have ideal clinical and personal care training to contribute to the team.

Conclusions

An ED-based multidisciplinary consultation service has potential to impact care for elder abuse victims. Insights from providers will inform intervention development.
Right ventricle to pulmonary artery coupling in patients undergoing transcatheter aortic valve implantation
Authors: Sultan Ibrahim , Cardounel Arturo , Abdelkarim Islam , Kilic Arman , Althouse Andrew D , Sharbaugh Michael S , Gupta Aman , Xu Jeff , Fukui Miho , Simon Marc A , Schindler John T , Lee Joon S , Gleason Thomas G , Cavalcante João L
Published: August 2018

Objectives

To evaluate the prognostic value of the ratio between tricuspid annular plane systolic excursion (TAPSE)-pulmonary artery systolic pressure (PASP) as a determinant of right ventricular to pulmonary artery (RV-PA) coupling in patients undergoing transcatheter aortic valve replacement (TAVI).

Background

RV function and pulmonary hypertension (PH) are both prognostically important in patients receiving TAVI. RV-PA coupling has been shown to be prognostic important in patients with heart failure but not previously evaluated in TAVI patients.

Methods

Consecutive patients with severe aortic stenosis who received TAVI from July 2011 through January 2016 and with comprehensive baseline echocardiogram were included. All individual echocardiographic images and Doppler data were independently reviewed and blinded to the clinical information and outcomes. Cox models quantified the effect of TAPSE/PASP quartiles on subsequent all-cause mortality while adjusting for confounders.

Results

A total of 457 patients were included with mean age of 82.8±7.2 years, left ventricular ejection fraction (LVEF) 54%±13%, PASP 44±17 mm Hg. TAPSE/PASP quartiles showed a dose-response relationship with survival. This remained significant (HR for lowest quartile vs highest quartile=2.21, 95% CI 1.07 to 4.57, p=0.03) after adjusting for age, atrial fibrillation, LVEF, stroke volume index, Society of Thoracic Surgeons Predicted Risk of Mortality.

Conclusion

Baseline TAPSE/PASP ratio is associated with all-cause mortality in TAVI patients as it evaluates RV systolic performance at a given degree of afterload. Incorporation of right-side unit into the risk stratification may improve optimal selection of patients for TAVI.
Woman in her 50s with shortness of breath on exertion
Authors: Konishi Takao , Murakami Hironori , Tanaka Shinya
Published: August 2018

Clinical introduction

A 59-year-old woman visited an outpatient cardiology clinic due to shortness of breath on exertion. Physical examination showed no significant abnormality of vital signs. A III/VI systolic murmur was heard on the fourth intercostal space at the right sternal border. The majority of laboratory tests were normal. Chest X-ray showed a curved vessel shadow (figure 1A). Initial transthoracic echocardiography showed abnormal blood flow into the inferior vena cava (IVC) in the subxiphoid long axis view (figure 1B) and mild right heart dilatation (online supplementary figure 1). Transoesophageal echocardiography showed severe tricuspid regurgitation (online supplementary figure 2).

Figure 1

(A) Chest X-ray. (B) Colour Doppler image in the subxiphoid long axis view.

Supplementary data

Supplementary data

Question

What is the most likely underlying disease for the patient’s shortness of breath on exertion?

Pulmonary arteriovenous fistula.

Pulmonary arterial hypertension.

Lung cancer.

Partial anomalous pulmonary venous connection.

Isolated tricuspid regurgitation.
Biomarkers for the diagnosis of venous thromboembolism: D-dimer, thrombin generation, procoagulant phospholipid and soluble P-selectin
Authors: Riva Nicoletta , Vella Kevin , Hickey Kieron , Bertù Lorenza , Zammit Daniel , Spiteri Silvana , Kitchen Steve , Makris Michael , Ageno Walter , Gatt Alex
Published: August 2018

Background

The diagnostic algorithm for venous thromboembolism (VTE) currently involves a composite of pre-test probability, D-dimer and imaging. Other laboratory tests, however, may assist in the identification of patients with VTE.

Aim

To assess the accuracy of different coagulation tests (D-dimer, thrombin generation, phospholipid-dependent (PPL) clotting time, soluble P-selectin (sP-selectin)) as biomarkers of acute VTE.

Methods

Random samples arriving at the Coagulation Laboratory at Mater Dei Hospital (Msida, Malta) from the Accident and Emergency Department with a request for D-dimer measurement were collected between August 2015 and February 2016. The following tests were performed: Innovance D-dimer (Siemens Healthcare Diagnostics), HemosIL D-dimer HS (Instrumentation Laboratory), thrombin generation (using the calibrated automated thrombogram), STA Procoag PPL (Diagnostica Stago) and sP-selectin (Affymetrix; eBioscience). VTE was objectively confirmed by compression ultrasonography, CT pulmonary angiography or ventilation/perfusion lung scan.

Results

100 samples were collected (33 with VTE). A strong positive linear correlation was found between the two D-dimer tests (r=0.97, p<0.001). Patients with VTE showed significantly higher sP-selectin concentrations compared with patients without VTE (75.7 ng/mL vs 53.0 ng/mL, p<0.001). In the random forest plot, the two D-dimer assays showed the highest variable importance, followed by sP-selectin. A sP-selectin cut-off of 74.8 ng/mL was associated with 72.7% sensitivity and 78.2% specificity for acute VTE in our cohort.

Conclusion

Our results confirmed D-dimer as the main biomarker of VTE and speculated a role for sP-selectin. The impact of thrombin generation was limited and no role emerged for the PPL clotting time. These observations need to be confirmed in large management studies.
Tobacco company strategies to identify and promote the benefits of nicotine
Authors: Ling Pamela M , Glantz Stanton A
Published: August 2018

Background

In response to a changing regulatory and consumer landscape, tobacco companies developed new strategies to promote cigarettes and smoking. We examined one of these strategies: to fund and conduct scientific research related to potential benefits of nicotine, and to use their findings to promote nicotine.

Methods

Qualitative analysis of previously secret tobacco industry documents from the Truth (formerly Legacy) Tobacco Documents Library (industrydocuments.library.ucsf.edu/tobacco), triangulated with data from other sources, including the online search engine Google, from the 1970s to December 2017.

Results

After publication of the 1988 Surgeon General’s report on nicotine addiction, tobacco companies (particularly RJ Reynolds) intensified efforts to promote the benefits of nicotine while downplaying its addictiveness and health risks. Activities included building relationships with academic institutions and funding scientific studies of the benefits of nicotine on cognition and other performance areas through intramural and extramural programmes. Companies then promoted their research findings through public relations campaigns, often minimising nicotine’s health risks by comparing it to caffeine or coffee. These comparisons appeared in highly publicised scientific meetings and interviews with the press. Nicotine-positive messages reappeared in the popular press and on some company websites in the 2010s.

Conclusions

Tobacco companies implemented strategies to promote benefits of nicotine to scientific and general audiences while minimising its health risks. These strategies reappeared at the time novel tobacco products like electronic cigarettes were introduced. A greater awareness of the source of claims related to purported benefits of nicotine could inform discussions about emerging tobacco products.
Distributional health and financial benefits of increased tobacco taxes in Colombia: results from a modelling study
Authors: James Erin Kinsella , Saxena Akshar , Franco Restrepo Camila , Llorente Blanca , Vecino-Ortiz Andres I , Villar Uribe Manuela , Iunes Roberto F , Verguet Stéphane
Published: August 2018

Background

In Colombia, smoking is the second leading modifiable risk factor for premature mortality. In December 2016, Colombia passed a major tax increase on tobacco products in an effort to decrease smoking and improve population health. While tobacco taxes are known to be highly effective in reducing the prevalence of smoking, they are often criticised as being regressive in consumption. This analysis attempts to assess the distributional impact (across socioeconomic groups) of the new tax on selected health and financial outcomes.

Methods

This study builds on extended cost-effectiveness analysis methods to study the new tobacco tax in Colombia, and estimates, over a time period of 20 years and across income quintiles of the current urban population (80% of the country population), the years of life gained with smoking cessation and the increased tax revenues, all associated with a 70% relative price increase of the pack of cigarettes. Where possible, we use parameters that vary by income quintile, including price elasticity of demand for cigarettes (average of −0.44 estimated from household survey data).

Findings

Over 20 years, the tax increase would lead to an estimated 191 000 years of life gained among Colombia’s current urban population, with the largest gains among the bottom two income quintiles. The additional annual tax revenues raised would amount to about 2%–4% of Colombia’s annual government health expenditure, with the poorest quintiles bearing the smallest tax burden increase.

Conclusions

The tobacco tax increase passed by Colombia has substantial implications for the country’s population health and financial well-being, with large benefits likely to accrue to the two poorest quintiles of the population.
We need to make more use of technology in the slaughter industry to improve welfare
Authors: Pinillos Rebeca García
Published: August 2018

Rebeca García Pinillos explains how the use of advanced technologies could help drive forward improvements in farm animal welfare during slaughter processes, as well as staff wellbeing.
Reliability-based design of internal limit states for mechanically stabilized earth walls using geosynthetic reinforcement
Authors: Bathurst Richard J. , Lin Peiyuan , Allen Tony
Published: August 2018

This paper demonstrates reliability-based design for tensile rupture and pullout limit states for mechanically stabilized earth (MSE) walls constructed with geosynthetic (geogrid) reinforcement. The general approach considers the accuracy of the load and resistance models that appear in each limit state equation plus uncertainty due to the confidence (level of understanding) of the designer at the time of design. The reliability index is computed using a closed-form solution that is easily implemented in a spreadsheet. The general approach provides a quantitative link between nominal factor of safety, which is familiar in allowable stress design practice, and reliability index used in modern civil engineering reliability-based design practice. A well-documented MSE wall case study is used to demonstrate the general approach and to compare margins of safety using different load and resistance model combinations. A practical outcome from the case study example is the observation that the pullout limit state is much less likely to control design than the ultimate tensile rupture state for walls with continuous reinforcement coverage. The more accurate “simplified stiffness method” that is used to compute tensile loads in the reinforcement under operational conditions is shown to generate a more cost-effective reinforcement option than the less accurate American Association of State Highway and Transportation Officials (AASHTO) simplified method.
Characterization of the GATA gene family in Vitis vinifera: genome-wide analysis, expression profiles, and involvement in light and phytohormone response
Authors: Zhang Zhan , Ren Chong , Zou Luming , Wang Yi , Li Shaohua , Liang Zhenchang
Published: August 2018

The plant GATA family is one of the most important transcription factors involved in light-responsive development, nitrogen metabolism, phytohormone signaling, and source/sink balance. However, the function of the GATA gene is less known in grape (Vitis vinifera L.). In this study, we comprehensively analyzed the GATA family in grape, particularly the phylogenetic evolution, duplication patterns, conserved motifs, gene structures, cis-elements, tissue expression patterns, and predicted function of VvGATA genes in response to abiotic stress. The potential roles of VvGATA genes in berry development were also investigated. The GATA transcription factors displayed expression diversity among different grape organs and tissues, and some of them showed preferential expression in a specific tissue. Heterotrophic cultured cells were used as model systems for the functional characterization of the VvGATA gene and study of its response to light and phytohormone. Results indicated that some VvGATA genes displayed differential responses to light and phytohormones, suggesting their role in light and hormone signaling pathways. A thorough analysis of GATA transcription factors in grape (V. vinifera L.) presented the characterization and functional prediction of VvGATA genes. The data presented here lay the foundation for further functional studies of grape GATA transcription factors.
Fortran Geezers
Authors: Hendrikson Dick
Published: August 2018

There was a reunion of the J3/WG5 Fortran old timers, the "geezers", on June 9th and 10th; just before the joint J3/WG5 meeting in Oakland CA. 25 people attended parts of the reunion. 18 were old enough to be true Fortran geezers; many joined the committee back in the 70s. Another 3 or 4 qualified by age to be a geezer, but are still too active on J3/WG5 to be a real old geezer. The remaining 3 or 4 are way to young to be geezers and just dropped by to visit with former colleagues or make new friends.
The h2m-AutoFortran tool for facilitating C-Fortran interoperability
Authors: Anderson Michelle , Liu Sisi Garnet , Nagle Daniel
Published: August 2018

Large, high-performance programs are often written in Fortran. Modern Fortran supports interoperability with C, which is beneficial because many useful libraries expose a C language interface. However, manually preparing the Fortran interfaces for each routine in a substantial C library to properly link a Fortran program can be time consuming. The h2m-AutoFortran tool can greatly simplify this process by harnessing the power of the Clang Compiler's abstract syntax tree to analyse C header files and translate them into corresponding interoperable Fortran modules. The resulting module may then be compiled and used in the Fortran program, providing correct access to procedures and data in the library.
Maintenance of contractile function of isolated airway smooth muscle after cryopreservation
Authors: Ijpma Gijs , Liang Chu Qiao , Kachmar Linda , Panariti Alice , Benedetti Andrea , Lavoie Jean-Pierre , Lauzon Anne-Marie
Published: August 2018

Isolated human airway smooth muscle (ASM) tissue contractility studies are essential for understanding the role of ASM in respiratory disease, but limited availability and cost render storage options necessary for optimal use. However, to our knowledge, no comprehensive study of cryopreservation protocols for isolated ASM has been performed to date. We tested several cryostorage protocols on equine trachealis ASM using different cryostorage media [1.8 M dimethyl sulfoxide and fetal bovine serum (FBS) or Krebs-Henseleit (KH)] and different degrees of dissection (with or without epithelium and connective tissues attached) before storage. We measured methacholine (MCh), histamine, and isoproterenol (Iso) dose-responses and electrical field stimulation (EFS) and MCh force-velocity curves. We confirmed our findings in human trachealis ASM stored undissected in FBS. Maximal stress response to MCh was decreased more in dissected than undissected equine tissues. EFS force was decreased in all equine but not in human cryostored tissues. Furthermore, in human cryostored tissues, EFS maximal shortening velocity was decreased, and Iso response was potentiated after cryostorage. Overnight incubation with 0.5 or 10% FBS did not recover contractility in the equine tissues but potentiated Iso response. Overnight incubation with 10% FBS in human tissues showed maximal stress recovery and maintenance of other contractile parameters. ASM tissues can be cryostored while maintaining most contractile function. We propose an optimal protocol for cryostorage of ASM as undissected tissues in FBS or KH solution followed by dissection of the ASM bundles and a 24-h incubation with 10% FBS before mechanics measurements.
Losartan has no additive effect on the response to heavy-resistance exercise in human elderly skeletal muscle
Authors: Heisterberg Mette Flindt , Andersen Jesper L. , Schjerling Peter , Lund Alberte , Dalskov Simone , Jønsson Anders Overgård , Warming Nichlas , Fogelstrøm Mathilde , Kjaer Michael , Mackey Abigail L.
Published: August 2018

Our purpose here was to investigate the potential of blocking the angiotensin II type I receptor (AT1R) on the hypertrophy response of elderly human skeletal muscle to 4 mo of heavy-resistance exercise training. Fifty-eight healthy elderly men (+65 yr) were randomized into three groups, consuming either AT1R blocker (losartan, 100 mg/day) or placebo for 4 mo. Two groups performed resistance training (RT) and were treated with either losartan or placebo, and one group did not train but was treated with losartan. Quadriceps muscle biopsies, MR scans, and strength tests were performed at baseline and after 8 and 16 wk. Biopsies were sectioned for immunohistochemistry to determine the number of satellite cells, capillaries, fiber type distribution, and fiber area. Gene expression levels of myostatin, connective tissue, and myogenic signaling pathways were determined by real-time RT-PCR. Four months of heavy-resistance training led in both training groups to expected improvements in quadriceps (∼3–4%) and vastus lateralis (∼5–6%), cross-sectional area, and type II fiber area (∼10–18%), as well as dynamic (∼13%) and isometric (∼19%) quadriceps peak force, but with absolutely no effect of losartan on these outcomes. Furthermore, no changes were seen in satellite cell number with training, and most gene targets failed to show any changes induced by training or losartan treatment. We conclude that there does not appear to be any effect of AT1R blocking in elderly men during 4 mo of resistance training. Therefore, we do not find any support for using AT1R blockers for promoting muscle adaptation to training in humans.

NEW & NOTEWORTHY Animal studies have suggested that blocking angiotensin II type I receptor (AT1R) enhances muscle regeneration and prevents disuse atrophy, but studies in humans are limited. Focusing on hypertrophy, satellite cells, and gene expression, we found that AT1R blocking did not result in any greater responses with 4 mo of resistance training. These results do not support previous findings and question the value of blocking AT1R in the context of preserving aging human muscle.
Lower cutaneous microvascular reactivity in adult cancer patients receiving chemotherapy
Authors: Sutterfield S. L. , Caldwell J. T. , Post H. K. , Lovoy G. M. , Banister H. R. , Ade C. J.
Published: August 2018

Cancer patients with a history of anticancer chemotherapy are at an increased cardiovascular disease risk compared with cancer-free populations. Therefore, we tested the hypothesis that cancer patients receiving adjuvant chemotherapy would have a lower cutaneous microvascular reactivity and lower endothelium-dependent flow-mediated dilation (FMD) of the brachial artery compared with matched cancer-free control subjects. To test this hypothesis, we performed a case control study with seven cancer patients receiving adjuvant chemotherapy and seven matched healthy reference control subjects. Red blood cell flux was measured as an index of cutaneous blood flow via laser Doppler flowmetry. Acetylcholine (ACh)-mediated vasodilation was determined by iontophoresis. Data were expressed as percent increase in cutaneous vascular conductance. Endothelium-dependent FMD of the brachial artery via ultrasonography was determined as an index of macrovessel endothelial function. Cutaneous microvascular reactivity was attenuated in cancer patients compared with control subjects [cancer: 959.9 ± 187.3%, control: 1,556.8 ± 222.2%; P = 0.03, effect size (ES) = 1.1]. Additionally, cancer patients demonstrated a significantly lower area under the curve response to ACh iontophoresis compared with healthy control subjects. Brachial artery FMD was also significantly lower in cancer patients compared with control subjects (cancer: 2.2 ± 0.6%, control: 6.6 ± 1.4%; P = 0.006, ES = 1.6), which was significantly associated with measurements of microvascular reactivity. These findings suggest that decreases in vascular reactivity can occur during cancer chemotherapy, which may have implications for the long-term risk of cardiovascular disease morbidity and mortality.

NEW & NOTEWORTHY Cancer survivors treated with chemotherapy experience an increased risk of cardiovascular events, linked to both cardiac and vascular toxicity. The major finding of this study is that microvascular reactivity and macrovascular endothelium-dependent flow-mediated dilation are lower in cancer patients currently receiving adjuvant chemotherapy compared with healthy counterparts.
Design and Mechanical Analysis of Bionic Foldable Beetle Wings
Authors: Wang Caidong , Wang Chen , Ning Yu , Chen Lumin , Wang Xinjie
Published: August 2018

In order to improve the flight performance of collapsible aircrafts, a novel mechanism of bionic foldable wings of beetle is designed based on the four-plate mechanism theory. The folding and unfolding movements of the bionic foldable wings are driven by motor and torsion hinges. Based on the D-H method, a kinematic model of wings is established to analyze the dihedral angle of adjacent plates. The folding ratio of an area in different plate creasing angles has been derived and calculated. Utilizing the kinematic and static models produced, as well as considering the folding ratio and output motor torque, the optimal physical parameters of folding wings are obtained. Dynamic models of rigid and flexible wings were established using ADAMS, and a motion simulation was performed. The relationship between dihedral angle and torque during the folding process of both rigid and flexible wings was obtained. The results provide a better understanding of the folding mechanism through the formulation of rigid-flexible wing analysis, as well as demonstrating a novel design of insect-mimicking artificial wings for small aerial vehicles.