bluuebunny/crossref_metadata_2025 huggingface dataset:
Verbal autopsy in health policy and systems: a literature review
Authors: Thomas Lisa-Marie , D’Ambruoso Lucia , Balabanova Dina
Published: May 2018

Introduction

Estimates suggest that one in two deaths go unrecorded globally every year in terms of medical causes, with the majority occurring in low and middle-income countries (LMICs). This can be related to low investment in civil registration and vital statistics (CRVS) systems. Verbal autopsy (VA) is a method that enables identification of cause of death where no other routine systems are in place and where many people die at home. Considering the utility of VA as a pragmatic, interim solution to the lack of functional CRVS, this review aimed to examine the use of VA to inform health policy and systems improvements.

Methods

A literature review was conducted including papers published between 2010 and 2017 according to a systematic search strategy. Inclusion of papers and data extraction were assessed by three reviewers. Thereafter, thematic analysis and narrative synthesis were conducted in which evidence was critically examined and key themes were identified.

Results

Twenty-six papers applying VA to inform health policy and systems developments were selected, including studies in 15 LMICs in Africa, Asia, the Middle East and South America. The majority of studies applied VA in surveillance sites or programmes actively engaging with decision makers and governments in different ways and to different degrees. In the papers reviewed, the value of continuous collection of cause of death data, supplemented by social and community-based investigations and underpinned by electronic data innovations, to establish a robust and reliable evidence base for health policies and programmes was clearly recognised.

Conclusion

VA has considerable potential to inform policy, planning and measurement of progress towards goals and targets. Working collaboratively at sub-national, national and international levels facilitates data collection, aggregation and dissemination linked to routine information systems. When used in partnerships between researchers and authorities, VA can help to close critical information gaps and guide policy development, implementation, evaluation and investment in health systems.
Pregnant women who requested a ‘108’ ambulance in two states of India
Authors: Singh Samiksha , Doyle Pat , Campbell Oona Maeve Renee , Rao Govindaraju Venkata Ramana , Murthy Gudlavalleti V S
Published: May 2018

We studied the pregnant women, who requested a ‘108’ ambulance in two Indian states (Andhra Pradesh (AP) and Himachal Pradesh (HP)). We conducted a cross-sectional telephone survey to study the characteristics and outcomes of those who (1) were transported using ‘108’ ambulance, (2) were sent ‘108’ ambulance but did not use it and (3) were not assigned a ‘108’ ambulance. We conducted interviews within 24 hours of clients’ call and followed them up at 48 hours, on the 7th and 28th day. 90% of pregnant women callers in AP and only 16% in HP were from poorer socioeconomic circumstances. 22.5% of women who were not provided an ambulance in HP lived in tribal areas. A higher proportion of women who were transported using ‘108’ reported either a high-risk condition (AP, 22%; HP, 27%) or an early complication in pregnancy (AP and HP, 16%), compared with the other groups (AP, 18% and 8%; HP, 19% and 16%). In AP, women who were sent an ambulance but did not use it had higher prevalence of obstetric emergency (9.8%) compared with the other groups (ambulance used, 7.4%; not assigned, 4.1%). One-fifth of women in AP and one-seventh in HP delivered by caesarean section. One woman who called, but was not transported by ‘108’, died in AP. Ten stillbirths and 22 neonatal deaths were reported in AP and 17 and 16, respectively, in HP. Strategies are required to improve ‘108’ service for tribal areas in HP. The ‘108’ services should be improved to reduce non-use of ambulance, especially for women who report obstetric emergencies.
Insulin sensitivity assessed using urine C peptide creatinine ratio (UCPCR) in pregnancy: cross-sectional analysis of an English multiethnic cohort
Authors: Markoska Ankica , Mendoza Lilian C , Valaiyapathi Rajalakshmi , Thorn Chloe , Dornhorst Anne
Published: May 2018

Aims

To assess urinary C peptide creatinine ratio (UCPCR) used in a modified Matsuda equation to measure insulin sensitivity (IS) in pregnancy.

Research and design methods

In this cross-sectional study, two IS measurements were calculated in 73 pregnant women at ~28 weeks of gestation by two separate methods using modified Matsuda equations. The first using the 0 and 120 min serum C peptide concentration during a 75 g oral glucose tolerance test (OGTT) and the second using the 0 and 120 min UCPCR values. The calculated IS measurements from the two methodologies were evaluated using Person’s test and linear regression analysis. The relationship between ISOGTTUCPCR and the fasting second void UCPCR and 120 min UCPCR was assessed using Pearson correlation and linear regression analysis after logarithmic transformation of the variables. Statistical analysis was performed using SPSS V.22.

Results

The IS measured using serum C peptide (ISOGTTc-pep) in the modified Matsuda equation correlated with the IS measurement using serum UCPCR (ISOGTT-UCPCR) (r 0.704, p<0.0001). A strong correlation was found between the ISOGTT-UCPCRand the fasting UCPCR (r −0.916, p<0.0001), displaying a hyperbolic relationship.

Conclusion

The UCPCR provides a practical methodology to assess IS and β-cell function in pregnancy.
Gender disparities in first medical contact and delay in ST-elevation myocardial infarction: a prospective multicentre Swedish survey study
Authors: Sederholm Lawesson Sofia , Isaksson Rose-Marie , Ericsson Maria , Ängerud Karin , Thylén Ingela
Published: May 2018

Objectives

Compare gender disparities in ST-elevation myocardial infarction (STEMI) regarding first medical contact (FMC) and prehospital delay times and explore factors associated with prehospital delay in men and women separately.

Design

Cross-sectional study based on medical records and a validated questionnaire. Eligible patients were enrolled within 24 hours after admittance to hospital.

Setting

Patients were included from November 2012 to January 2014 from five Swedish hospitals with catheterisation facilities 24/7.

Participants

340 men and 109 women aged between 31 and 95 years completed the survey.

Main outcome measures

FMC were divided into five possible contacts: primary healthcare centre by phone or directly, national advisory nurse by phone, emergency medical services (EMS) and emergency room directly. Two parts of prehospital delay times were studied: time from symptom onset to FMC and time from symptom onset to diagnostic ECG.

Results

Women more often called an advisory nurse as FMC (28% vs 18%, p=0.02). They had a longer delay until FMC, 90 (IQR 39–221) vs 66 (28–161) min, p=0.04 and until ECG, 146 (68–316) vs 103 (61–221) min, p=0.03. Men went to hospital because of believing they were stricken by an MI to a higher extent than women did (25% vs 15%, p=0.04) and were more often recommended to call EMS by bystanders (38% vs 22%, p<0.01). Hesitating about going to hospital and experiencing pain in the stomach/back/shoulders were factors associated with longer delays in women. Believing the symptoms would disappear or interpreting them as nothing serious were corresponding factors in men. In both genders bystanders acting by contacting EMS explained shorter prehospital delays.

Conclusions

In STEMI, women differed from men in FMC and they had longer delays. This was partly due to atypical symptoms and a longer decision time. Bystanders acted more promptly when men than when women fell ill. Public knowledge of MI symptoms, and how to act properly, still seems insufficient.
Determinants of seat belt use behaviour: a protocol for a systematic review
Authors: Ghaffari Mohtasham , Armoon Bahram , Rakhshanderou Sakineh , Mehrabi Yadollah , Soori Hamid , Simsekoghlu Ozelem , Harooni Javad
Published: May 2018

Introduction

The use of seat belts could prevent severe collision damage to people in vehicle accidents and keep passengers safe from sustaining serious injuries; for instance, it could prevent passengers from being thrown out of a vehicle after the collision. The current systematic review will identify and analyse the determinants of seat belt use behaviour.

Methods and analysis

We will include qualitative, quantitative and mixed methods studies reporting the acquired data from passengers aged more than 12 years and drivers, from both commercial and personal vehicles. Online databases including MEDLINE/PubMed, Scopus, Web of Science, Embase, Cochrane Database of Systematic Reviews and PsycINFO will be investigated in the current study. Published and available articles will be evaluated according to their titles and abstracts. Published papers conforming to the inclusion criteria will be organised for a complete review. Next, the full text of the remaining articles will be studied independently for eligibility by two authors. The quality of the selected studies will be assessed with appropriate tools. Based on the information obtained from the data extraction, the type of determinants of seat belt use will be classified.

Ethics and dissemination

Ethics approval is not required, because this is a protocol for a systematic review and no primary data will be collected. The authors will ensure to maintain the rights of the used and included articles in the present systematic review. The findings of this review will be published in a relevant peer-reviewed journal.

PROSPERO registration number

CRD42017067511.
A novel method of topology identification for general complex dynamical networks with incomplete measurements
Authors: Wang Xinwei , Jiang Guo-Ping , Wu Xu
Published: May 2018

Recovering the topological structure of a general complex dynamical network with the incomplete measurements of transmitted drive states is investigated in this paper. The incomplete measurements, which cannot be ignored, have not been well considered in topology identification issue. Different from previous studies, we propose a novel method which can handle the situation of incomplete measurements well. The proposed method can fix the excessive deviation of the controller caused by the incomplete measurements, and overcome the special restrictions on the node dynamics raised by the previous methods. By means of LaSalle’s invariance principle, mathematical derivation of the mechanism is deduced rigorously to obtain the sufficient criteria in the form of linear matrix inequalities. Numerical simulations with the complex dynamical network composed of chaotic dynamical nodes are given to illustrate the effectiveness of our proposed method.
Individual T1-weighted/T2-weighted ratio brain networks: Small-worldness, hubs and modular organization
Authors: Wu Huijun , Wang Hao , Lü Linyuan
Published: May 2018

Applying network science to investigate the complex systems has become a hot topic. In neuroscience, understanding the architectures of complex brain networks was a vital issue. An enormous amount of evidence had supported the brain was cost/efficiency trade-off with small-worldness, hubness and modular organization through the functional MRI and structural MRI investigations. However, the T1-weighted/T2-weighted (T1w/T2w) ratio brain networks were mostly unexplored. Here, we utilized a KL divergence-based method to construct large-scale individual T1w/T2w ratio brain networks and investigated the underlying topological attributes of these networks. Our results supported that the T1w/T2w ratio brain networks were comprised of small-worldness, an exponentially truncated power–law degree distribution, frontal-parietal hubs and modular organization. Besides, there were significant positive correlations between the network metrics and fluid intelligence. Thus, the T1w/T2w ratio brain networks open a new avenue to understand the human brain and are a necessary supplement for future MRI studies.
Highway Deformation Monitoring Based on an Integrated CRInSAR Algorithm — Simulation and Real Data Validation
Authors: Xing Xuemin , Wen Debao , Chang Hsing-Chung , Chen Li Fu , Yuan Zhi Hui
Published: May 2018

Long-term surface deformation monitoring of highways is crucial to prevent potential hazards and ensure sustainable transportation system safety. DInSAR technique shows its great advantages for ground movements monitoring compared with traditional geodetic survey methods. However, the unavoidable influences of the temporal and spatial decorrelation have brought restrictions for traditional DInSAR on the application for ribbon infrastructures deformation monitoring. In addition, PS and SBAS techniques are not suitable for the area where adequate natural high coherent points cannot be detected. Due to this, we designed an integrated highway deformation monitoring algorithm based on CRInSAR technique in this paper, the processing flow including Corner Reflectors (CR) identification, CR baseline network establishment, phase unwrapping, and time series highway deformation estimation. Both the simulated and real data experiments are conducted to assess and validate the algorithm. In the scenario using simulated data, 10 different noise levels are added to test the performance under different circumstances. The RMSE of linear deformation velocities for 10 different noise levels are obtained and analyzed, to investigate how the accuracy varies with noise. In the real data experiment, part of a highway in Henan, China is chosen as the test area. Six PALSAR images acquired from 22 December 2008 to 09 February 2010 were collected and 12 CR points were installed along the highway. The ultimate time series deformation estimated show that all the CR points are stable. CR04 is undergoing the most serious subsidence, with the maximum magnitude of 13.71[Formula: see text]mm over 14 months. Field leveling measurements are used to assess the external deformation accuracy, the final RMSE is estimated to be [Formula: see text][Formula: see text]mm, which indicates good accordance with the result of leveling.
A Low-Noise Dynamic Comparator with Offset Calibration for CMOS Image Sensor Architecture
Authors: Sathishkumar Arumugam , Saravanan Siddhan
Published: May 2018

A low-noise, high-speed, low-input-capacitance switched dynamic comparator (SDC) CMOS image sensor architecture is presented in this paper. The comparator design occupying less area and consuming lesser power is suitable for bank of comparators in CMOS image readouts. The proposed dynamic comparator eliminates the stacking issue related to the conventional comparator and reduces the offset noise further. The need for low-noise, low-power, area-efficient and high-speed flash analog-to-digital converters (ADCs) in many applications today motivated us to design a comparator for ADC. The rail-to-rail output swing is also improved. The input capacitance is reduced by using shared first-stage technique. The comparator is designed with constant [Formula: see text]/[Formula: see text] biasing to suppress the environmental drift. The simulation results from 45-nm and 65-nm CMOS technologies confirm the analysis results. It is shown that in the proposed dynamic comparator both the power consumption and delay time are significantly reduced. The maximum clock frequency of the proposed comparator can be increased to 3.5[Formula: see text]GHz and 2.2[Formula: see text]GHz at supply voltages of 1[Formula: see text]V and 0.6[Formula: see text]V, respectively. Simulations are carried out using predictive technology models for 45[Formula: see text]nm and 65[Formula: see text]nm in HSPICE.
FPGA-Based Hardware Accelerator for an Embedded Factor Graph with Configurable Optimization
Authors: Sugiarto Indar , Axenie Cristian , Conradt Jörg
Published: May 2018

A factor graph (FG) can be considered as a unified model combining a Bayesian network (BN) and a Markov random field (MRF). The inference mechanism of a FG can be used to perform reasoning under incompleteness and uncertainty, which is a challenging task in many intelligent systems and robotics. Unfortunately, a complete inference mechanism requires intense computations that introduces a long delay for the reasoning process to complete. Furthermore, in an energy-constrained system such as a mobile robot, it is required to have a very efficient inference process. In this paper, we present an embedded FG inference engine that employs a neural-inspired discretization mechanism. The engine runs on a system-on-chip (SoC) and is accelerated by its FPGA. We optimized our design to balance the trade-off between speed and hardware resource utilization. In our fully-optimized design, it can accelerate the inference process eight times faster than the normal execution, which is twice the speed-up gain achieved by a parallelized FG running on a PC. The experiments demonstrate that our design can be extended into an efficient reconfigurable computing machine.
Are there really conformal frames? Uniqueness of affine inflation
Authors: Azri Hemza
Published: May 2018

Here, we concisely review the nonminimal coupling dynamics of a single scalar field in the context of purely affine gravity and extend the study to multifield dynamics. The coupling is performed via an affine connection and its associated curvature without referring to any metric tensor. The latter arises a posteriori and it may gain an emergent character like the scale of gravity. What is remarkable in affine gravity is the transition from nonminimal to minimal couplings which is realized by only field redefinition of the scalar fields. Consequently, the inflationary models gain a unique description in this context where the observed parameters, like the scalar tilt and the tensor-to-scalar ratio, are invariant under field reparametrization. Overall, gravity in its affine approach is expected to reveal interesting and rich phenomenology in cosmology and astroparticle physics.
FABRICATION AND CHARACTERIZATION OF TiO2 THIN FILM FOR DEVICE APPLICATIONS
Authors: HOSSEINI A. , GÜLLÜ H. H. , COSKUN E. , PARLAK M. , ERCELEBI C.
Published: May 2018

Titanium oxide (TiO2) film was deposited by rectification factor (RF) magnetron sputtering technique on glass substrates and p-Si (111) wafers to fabricate n-TiO2/p-Si heterojunction devices for the investigation of material and device properties, respectively. The structural, surface morphology, optical and electrical properties of TiO2 film were characterized by means of scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), UV–visual (UV–Vis) spectral and dark current-voltage (I–V) measurement analyses. The deposited film layer was found to be homogeneous structure with crack-free surface. The bandgap value of TiO2 film was determined as 3.6[Formula: see text]eV and transmission was around 65–85% in the spectral range of 320–1100[Formula: see text]nm. The conductivity type of the deposited film was determined as n-type by hot probe method. These values make TiO2 film a suitable candidate as the n-type window layer in possible diode applications. TiO2 film was also deposited on p-Si (111) wafer to obtain Al/n-TiO2/p-Si/Al heterojunction device structure. The dark I–V characteristic was studied to determine the possible conduction mechanisms and diode parameters.
Further Revelation on Damage Detection by IAS Computed from the Contact-Point Response of a Moving Vehicle
Authors: Yang Y. B. , Zhang Bin , Qian Yao , Wu Yuntian
Published: May 2018

The instantaneous amplitude squared (IAS) of the driving component of the contact-point response of a moving test vehicle was proposed for the damage detection of the sustaining bridge. As a supplement to the properties previously presented for the IAS, this paper is aimed at unveiling the key feature of the discontinuity amplification inherent in the IAS through the double guarantee of a “square operation” in the definition and a “second derivative” in computing the contact-point response. The capability of the IAS was demonstrated with regard to the effects of the environmental noise, vehicle damping and bridge damping in the numerical simulation. It is confirmed that the IAS can be reliably used in the damage detection of bridges by a moving test vehicle.
Free Vibration and Elastic Critical Load of Functionally Graded Material Thin Cylindrical Shells Under Internal Pressure
Authors: Han Yueyang , Zhu Xiang , Li Tianyun , Yu Yunyan , Hu Xiaofang
Published: May 2018

An analytical approach for predicting the free vibration and elastic critical load of functionally graded material (FGM) thin cylindrical shells filled with internal pressured fluid is presented in this study. The vibration of the FGM cylindrical shell is described by the Flügge shell theory, where the internal static pressure is considered as the prestress term in the shell equations. The motion of the internal fluid is described by the acoustic wave equation. The natural frequencies of the FGM cylindrical shell under different internal pressures are obtained with the wave propagation method. The relationship between the internal pressure and the natural frequency of the cylindrical shell is analyzed. Then the linear extrapolation method is employed to obtain the elastic critical load of the FGM cylindrical shell from the condition that the increasing pressure has resulted in zero natural frequency. The accuracy of the present method is verified by comparison with the published results. The effects of gradient index, boundary conditions and structural parameters on the elastic critical load of the FGM cylindrical shell are discussed. Compared with the experimental and numerical analyses based on the external pressure, the present method is simple and easy to carry out.
Experimental Investigation on Hardness Properties of Laser Hardened Bead Profile of Commercially Pure Titanium Grade3 Using Nd:YAG Laser
Authors: Badkar Duradundi Sawant
Published: May 2018

This research paper presents the laser transformation hardening (LTH) to improve the surface hardness of commercially pure titanium, nearer to ASTM Grade3 chemical composition of 1.6[Formula: see text]mm thickness sheet using a CW (continuous wave) 2[Formula: see text]kW, with radiation wavelength [Formula: see text][Formula: see text][Formula: see text]m Nd:YAG laser. Full factorial and response surface design approach in Design Expert 9 software have been discussed and evaluated by statistical regression analysis and analysis of variance. The experiment was carried out as the full factorial design (FFD) array of 27 with 3 factors, 3 levels, i.e. 3[Formula: see text] experiments. The selected input parameters are: laser power, scanning speed and focused position, and responses are: Vickers Microhardness on top surface, in fusion zone, and in heat affected zone. FFD and response surface methodology (RSM) were applied to evaluate and optimize the effects of laser process parameters on Vickers microhardness of laser hardened surface. The results show that, the hardness of as-received commercially pure titanium is approximately 153[Formula: see text]VHN and the hardness after laser transformation hardened bead geometrical surface is in the range of 200–240[Formula: see text]VHN. The hardness can be increased with the increase in the scanning speed and decrease in the optimum value of laser power i.e. heat input applied. It has been found that the quadratic model is best fitted for prediction of the Vickers microhardness of laser hardened surface. These findings are significant in modern development of hard surface coatings for corrosion and wear resistant applications. Application of experimental results will be considered in the aerospace, marine, chemical, medicine, automobile and the engineering industries.
Association of Hemodynamic Behavior in the Thoracic Aortic Aneurysm to the Intraluminal Thrombus Prediction: A Two-Way Fluid Structure Coupling Investigation
Authors: Ong Chi Wei , Yap Choon Hwai , Kabinejadian Foad , Nguyen Yen Ngoc , Cui Fangsen , Chua Kian Jon , Ho Pei , Leo Hwa Liang
Published: May 2018

Clotting of blood elements or intraluminal thrombus (ILT) is known to develop within aortic aneurysm sacs, and is clinically associated with the dilation and rupturing of aneurysms. However, the underlying factors that generate ILT are still unclear. We hypothesize that ILT can form under the influence of unfavorable hemodynamic patterns. This paper presents evidence for one such type of flow dynamics that could give rise to ILT within the aneurysm sac. Image-based patient-specific fluid–structure-interaction modeling of three cases of thoracic aortic aneurysms was performed, using retrospective CT images to investigate the formation of ILT as a result of local hemodynamic of aneurysm. This study showed that the formation of the ILT was associated with a vortex observed near the aortic narrowing, upstream of the aneurysm sac. This vortex could subject the blood elements to elevated stresses before directing them into the sac. The recirculation flow within the aneurysm sac may trap these activated blood elements, thus, leading to the formation of ILT during early diastole. One primary cause for ILT, as indicated in this study, could be attributed to the sharp curvature at the aortic narrowing (or isthmus) that gives rise to the vortex. Our study also showed that the size and location of the aneurysm have a direct impact on the duration and location of the vortex, which could influence the formation of the ILT.
Thermoelastic Crack Analysis in Functionally Graded Pipelines Conveying Natural Gas by an FEM
Authors: Attia Mohamed A. , Eltaher Mohamed A. , Soliman Ahmed , Abdelrahman Alaa A. , Alshorbagy Amal E.
Published: May 2018

Internal cracks are a serious problem in pipelines conveying unsteady pressurized fluids like natural gas. To investigate and overcome this problem, this paper is motivated to highlight and study the response of gas pipes made of functionally graded materials (FGM) instead of the traditional carbon steel material. FGM is proposed as a composite material because of its advantages of minimizing the stress variation in the pipe. Ceramic is applied because of its durability against corrosion and its surface hardness against erosion. FGM properties are radially graded and a finite element model is developed and implemented into ABAQUS package, including FORTRAN subroutines which are adapted for the present case study. Coupled plane strain thermoelastic analysis is used to investigate the stresses and the stress intensity factor (SIF) at various crack depths under the actual thermomechanical loads. Both coupled and uncoupled thermomechanical approaches are introduced and compared to reveal the necessity of the coupled analysis for accurate FGMs’ investigation. The different influences of unsteady thermal and mechanical loads on the crack propagation are discussed.
Elasto-Plastic Modeling of Low-Velocity Impact on Functionally Graded Circular Plates
Authors: Mars Jamel , Said Lotfi Ben , Wali Mondher , Dammak Fakhreddine
Published: May 2018

Low-velocity impact of elasto-plastic functionally graded material (FGM) plates is first investigated in this paper based on Mori–Tanaka model to underline micromechanics and locally determine the effective FGM properties and self-consistent method of Suquet for the homogenization of the stress-field. The elasto-plastic behavior of the particle reinforced metal matrix FGM plate is assumed to follow Ludwik hardening law. An incremental formulation of the elasto-plastic constitutive relation is developed to predict the tangent operator. The homogenization formulation and numerical algorithms are implemented into ABAQUS/Standard via a user material subroutine (UMAT) and USDFLD subroutine. The effect of the power-law index on low-velocity impact parameters like contact force, deflection, permanent indentation, velocity distribution and the kinetic energy are examined using the proposed method. With the aim of demonstrating the accuracy and efficiency of the present method, current numerical results are compared to experimental and theoretical results from the literature and show very good agreement.
Bi-Directional Functionally Graded Nanotubes: Fluid Conveying Dynamics
Authors: Tang Ye , Yang Tianzhi
Published: May 2018

In the paper, a novel model of fluid-conveying nanotubes made of bi-directional functionally graded materials is presented for investigating the dynamic behaviors and stability. For the first time, the material properties of the nanotubes along both radical and axial directions are under consideration. Based on Euler–Bernoulli beam and Eringen’s nonlocal elasticity theories, the governing equation of the nanotubes and associated boundary conditions are developed using Hamilton’s principle. Differential quadrature method (DQM) is applied for discretizing the equation to determine the numerical solutions of the nanotubes with different boundary conditions. Numerical examples are presented to examine the effects of the material gradation, nonlocal parameter, and mode order on the dynamics and stability. It is shown that the two-directional materials distribution can significantly change the critical flow velocity, fundamental frequencies and stability. Comparing with traditional one-directional distribution, such 2D is more flexible to tune overall dynamic behaviors, this may provide new avenues for smart pipes.
Three-Dimensional Parametric Finite-Volume Homogenization of Periodic Materials with Multi-Scale Structural Applications
Authors: Chen Qiang , Wang Guannan , Chen Xuefeng
Published: May 2018

In order to satisfy the increasing computational demands of micromechanics, the Finite-Volume Direct Averaging Micromechanics (FVDAM) theory is developed in three-dimensional (3D) domain to simulate the multiphase heterogeneous materials whose microstructures are distributed periodically in the space. Parametric mapping, which endorses arbitrarily shaped and oriented hexahedral elements in the microstructure discretization, is employed in the unit cell solution. Unlike the finite-element (FE) technique, the expressions for local stiffness matrices are derived explicitly, enabling efficient global stiffness matrix assembly using an easily implementable algorithm. To demonstrate the accuracy and efficiency of the proposed theory, the homogenized moduli and localized stress distributions produced by the FE analyses are given for comparisons, where excellent agreement is always obtained for the 3D microstructures with different geometrical and material properties. Finally, a multi-scale stress analysis of functionally graded composite cylinders is conducted. This extension further increases the FVDAM’s range of applicability and opens new opportunities for pursuing other areas, providing an attractive alternative to the FE-based approaches that may be compared.
Simultaneous quantification of longitudinal and transverse ocular chromatic aberrations with Hartmann–Shack wavefront sensor
Authors: Deng Yangchun , Zhao Junlei , Dai Yun , Zhang Yudong
Published: May 2018

A simple method to objectively and simultaneously measure eye’s longitudinal and transverse chromatic aberrations was proposed. A dual-wavelength wavefront measurement system using two Hartmann–Shack wavefront sensors was developed. The wavefronts of the red (639.1[Formula: see text]nm) and near-infrared (786.0[Formula: see text]nm) lights were measured simultaneously for different positions in the model eye. The chromatic wavefronts were converted into Zernike polynomials. The Zernike tilt coefficient (first term) was used to calculate the transverse chromatic aberration along the [Formula: see text]-direction, while the Zernike defocus coefficient (fourth term) was used to calculate the longitudinal chromatic aberration. The measurement and simulation data were consistent.
Bottom of Pyramid 4.0: Modularising and Assimilating Industrial Revolution Cognition into a 4-Tiered Social Entrepreneurship Upliftment Model for Previously Disconnected Communities
Authors: Darwish H. , Van Dyk L.
Published: May 2018

Developing a sociopreneurial (social-entrepreneurship) ecosystem is a substantial long-term investment. Much like natural ecosystems, there are a multitude of support systems needed to maintain balance and diversity in sociopreneurial ecosystems and their interactions are complex in nature. Yet, the various benefits that arise from such ecosystems make them a worthwhile investment. Examples of this come from global universities and private companies who have succeeded in creating hubs of innovation and creativity in different cities around the world. These hubs have achieved commendable results and produced quality initiatives. Yet, there is little success beyond the walls of cities, especially in low income communities. Typically, Bottom of Pyramid (BoP) Entrepreneurs must either move to cities to make their entrepreneurial ambitions come true or settle for small business status. This is especially troubling given that their communities are often the ones that need their skills most. The article begins by discussing the concept of Bottom of the Pyramid (BoP) society. It argues that in the context of the knowledge era and the rise of the network society, the BoP is better named “the outer network society”. Using Industrial Engineering principles and systems thinking, the researcher designed a product range and upliftment model (collectively known as the ModulaRISE) that helps resolve most of the structural issues with developing a sustainable sociopreneurial ecosystem. The ModulaRISE model provides three core support structures that can assist in reversing this unfortunate brain drain: Education, Operation and Finance. Moreover, an overarching concern resolved with the model is the tiered system that helps bridge cognitive challenges of being exposed to Industry 4.0 futuristic technologies without the proper incentivized build up. The model has already been launched on a small scale with preliminary case studies showing significant promise. The vision is to develop a fully turn-key upliftment in a box model for BoP communities which connects them to the world and allows them to collaborate to mutually enrich their society and the global society. In concluding, it is discussed that since the majority of society (80%) lives in the outer network, it is fundamental for Industrial Engineers to help design new systems that connect these societies to resources (in the broadest sense) that can help them develop socio-economically and cognitively to be able integrate to the global network society.
Surficial sediment failures due to the 1929 Grand Banks Earthquake, St Pierre Slope
Authors: Schulten Irena , Mosher David C. , Krastel Sebastian , Piper David J. W. , Kienast Markus
Published: May 2018

A
M
w
7.2 earthquake centred beneath the upper Laurentian Fan of the SW Newfoundland continental slope triggered a damaging turbidity current and tsunami on 18 November 1929. The turbidity current broke telecommunication cables, and the tsunami killed 28 people and caused major infrastructure damage along the south coast of Newfoundland. Both events are believed to have been derived from sediment mass failure as a result of the earthquake. This study aims to identify the volume and kinematics of the 1929 slope failure in order to understand the geohazard potential of this style of sediment failure. Ultra-high-resolution seismic reflection and multibeam swath bathymetry data are used to determine: (1) the dimension of the failure area; (2) the thickness and volume of failed sediment; (3) fault patterns and displacements; and (4) styles of sediment failure. The total failure area at St Pierre Slope is estimated to be 5200 km
2
, recognized by escarpments, debris fields and eroded zones on the seafloor. Escarpments are typically 20–100 m high, suggesting failed sediment consisted of this uppermost portion of the sediment column. Landslide deposits consist mostly of debris flows with evidence of translational, retrogressive sliding in deeper water (>1700 m) and evidence of instantaneous sediment failure along fault scarps in shallower water (730–1300 m). Two failure mechanisms therefore seem to be involved in the 1929 submarine landslide: faulting and translation. The main surficial sediment failure concentrated along the deep-water escarpments consisted of widely distributed, translational, retrogressive failure that liquefied to become a debris flow and rapidly evolved into a massive channelized turbidity current. Although most of the surficial failures occurred at these deeper head scarps, their deep-water location and retrogressive nature make them an unlikely main contributor to the tsunami generation. The localized fault scarps in shallower water are a more likely candidate for the generation of the tsunami, but further research is needed in order to address the characteristics of these fault scarps.
Microvascularization is not a limiting factor for exercise in adults with cerebral palsy
Authors: Andersen Ida Torp , Harrison Adrian , Broholm Rikke , Harder Anja , Nielsen Jens Bo , Bülow Jens , Pingel Jessica
Published: May 2018

Muscle contractures are a common complication in patients with central nervous system (CNS) lesions which limit range of movement and cause joint deformities. Furthermore, it has previously been shown that muscles with contractures have a reduced number of capillaries, indicating decreased tissue vascularization. The aim of the present study was to investigate the microvascular volume (MV) at rest and after acute exercise in the muscle tissue of individuals with cerebral palsy (CP) and healthy control individuals. Contrast-enhanced ultrasound (CEUS) was used before and after 30 min of walking or running on a treadmill in 10 healthy control participants and 10 individuals with CP to detect MV of their skeletal muscle tissue. A significant increase in the MV was observed after exercise both in the adult CP group (21–53 yr) and in the control group (21–52 yr) (1.8 ± 0.8 ΔdB to 3.1 ± 0.9 ΔdB or 42.9% and 1.5 ± 0.6 ΔdB to 2.5 ± 0.9 ΔdB or 39.0%, respectively). Furthermore, a difference in the resting MV was observed between the most severe cases of CP [gross motor function classification scale (GMFCS) 3 and 4] (2.3 ± 0.5 ΔdB) and the less severe cases (GMFCS 1 and 2) (1.5 ± 0.2 ΔdB). When the CP group was walking (3.4 km/h), the lactate levels, Borg score, and heart rate matched the level of controls when they were running (9.8 km/h). In conclusion, individuals with CP become exhausted at much lower exercise intensities than healthy individuals. This is not explained by impaired microvascularization, since the MV of the individuals with CP respond normally to increased O2demand during acute exercise.

NEW & NOTEWORTHY Cerebral palsy (CP) patients were less physically active compared with typically developed individuals. This may affect the microvascularization. We observed that the CP group became exhausted at much lower exercise intensities compared with healthy individuals. However, impaired microvascularization was not the reason for the decreased physical activity as the CP group responded normally to increased O2demand during acute exercise. These results indicate that walking may be recommended as an intervention to train and maintain skeletal muscle tissue in individuals with CP.
Whole body vibration training increases physical measures and quality of life without altering inflammatory-oxidative biomarkers in patients with moderate COPD
Authors: Neves Camila D. C. , Lacerda Ana Cristina R. , Lage Vanessa K. S. , Soares Aline A. , Chaves Maria Gabriela A. , Lima Liliana P. , Silva Thyago J. , Vieira Érica L. M. , Teixeira Antônio L. , Leite Hércules R. , Matos Mariana A. , Mendonça Vanessa A.
Published: May 2018

Whole body vibration training (WBVT) has been identified as an alternative intervention to improve exercise capacity and quality of life of patients with chronic obstructive pulmonary disease (COPD). However, the effect of WBVT on inflammatory-oxidative biomarkers remains unknown. The aim of this trial was to investigate the effects of WBVT on quality of life and physical and inflammatory-oxidative parameters in patients with COPD. Twenty patients were equally divided into 1) an intervention group (IG) that performed the WBVT, and 2) a control group (CG) that did not receive any intervention. Intervention consisted in performing static squatting on a vibrating platform, in six series of 30 s, 3 days/wk, for 12 wk. Patients were evaluated for plasma levels of IL-6, IL-8, IFN-γ, soluble receptors of TNF-α; white cell count; plasma levels of oxidant and antioxidant markers; 6-min walking distance (6MWD); peak oxygen uptake (V̇o2peak); handgrip strength; quality of life; timed 5-chair sit-to-stand (5STS); and timed get-up and go test (TUG). After WBVT, patients from IG showed a significant increase in the 6MWD, V̇o2peak, and handgrip strength ( P < 0.05). Furthermore, patients from the IG reached minimal clinically important difference regarding quality of life. No significant differences were found in 5STS, TUG, inflammatory-oxidative biomarkers, and white cell count in the IG. The CG did not show significant improvement in all assessments ( P > 0.05). Taken together, our results demonstrated that the WBVT induced clinically significant benefits regarding exercise capacity, muscle strength, and quality of life in patients with COPD that were not related to inflammatory-oxidative biomarker changes.

NEW & NOTEWORTHY Whole body vibration training is a new option for nonpharmacological treatment of chronic obstructive pulmonary disease (COPD). This study showed the potential of this training to improve exercise capacity, quality of life, and muscle strength in patients with COPD. Furthermore, to our knowledge this was the first study showing that vibration exercise does not modify the plasma levels of inflammatory-oxidative biomarkers, suggesting that the beneficial effects on physical measures and quality of life are independent of changes in biomarkers.
Abundance of ClC-1 chloride channel in human skeletal muscle: fiber type specific differences and effect of training
Authors: Thomassen Martin , Hostrup Morten , Murphy Robyn M. , Cromer Brett A. , Skovgaard Casper , Gunnarsson Thomas P. , Christensen Peter M. , Bangsbo Jens
Published: May 2018

Cl−channel protein 1 (ClC-1) may be important for excitability and contractility in skeletal muscle, but ClC-1 abundance has not been examined in human muscle. The aim of the present study was to examine ClC-1 abundance in human skeletal muscle, including fiber type specific differences and the effect of exercise training. A commercially available antibody was tested with positive and negative control tissue, and it recognized specifically ClC-1 in the range from 100 to 150 kDa. Abundance of ClC-1 was 38% higher ( P < 0.01) in fast twitch Type IIa muscle fibers than in slow twitch Type I. Muscle ClC-1 abundance did not change with 4 wk of training consisting of 30 min cycling at 85% of maximal heart rate (HRmax) and 3 × 30-s all out sprints or during a 7-wk training period with 10–12 × 30 s uphill cycling and 4–5 × ~4 min cycling at 90%–95% of HRmax. ClC-1 abundance correlated negatively ( P < 0.01) with maximal oxygen consumption ( r = –0.552) and incremental exercise performance ( r = –0.546). In addition, trained cyclists had lower ( P < 0.01) ClC-1 abundance than lesser trained individuals. The present observations indicate that a low abundance of muscle ClC-1 may be beneficial for exercise performance, but the role of abundance and regulation of ClC-1 in skeletal muscle of humans with respect to exercise performance and trainability need to be elucidated.

NEW & NOTEWORTHY Abundance of the Cl−channel protein 1 (ClC-1) chloride channel may be important for excitability and contractility in human skeletal muscle and may therefore have implications for fatigue development. In this study, we confirmed ClC-1 specificity for a commercially available antibody, and this study is first to our knowledge to determine ClC-1 protein abundance in human muscle by Western blotting. We observed that abundance of ClC-1 was higher in fast compared with slow twitch fibers and lower in trained individuals than in recreationally active.
Cheap labor: myosin fiber type expression and enzyme activity in the forelimb musculature of sloths (Pilosa: Xenarthra)
Authors: Spainhower Kyle B. , Cliffe Rebecca N. , Metz Allan K. , Barkett Ernest M. , Kiraly Paije M. , Thomas Dylan R. , Kennedy Sarah J. , Avey-Arroyo Judy A. , Butcher Michael T.
Published: May 2018

Sloths are canopy-dwelling inhabitants of American neotropical rainforests that exhibit suspensory behaviors. These abilities require both strength and muscular endurance to hang for extended periods of time; however, the skeletal muscle mass of sloths is reduced, thus requiring modifications to muscle architecture and leverage for large joint torque. We hypothesize that intrinsic muscle properties are also modified for fatigue resistance and predict a heterogeneous expression of slow/fast myosin heavy chain (MHC) fibers that utilize oxidative metabolic pathways for economic force production. MHC fiber type distribution and energy metabolism in the forelimb muscles of three-toed ( Bradypus variegatus, n = 5) and two-toed ( Choloepus hoffmanni, n = 4) sloths were evaluated using SDS-PAGE, immunohistochemistry, and enzyme activity assays. The results partially support our hypothesis by a primary expression of the slow MHC-1 isoform as well as moderate expression of fast MHC-2A fibers, whereas few hybrid MHC-1/2A fibers were found in both species. MHC-1 fibers were larger in cross-sectional area (CSA) than MHC-2A fibers and comprised the greatest percentage of CSA in each muscle sampled. Enzyme assays showed elevated activity for the anaerobic enzymes creatine kinase and lactate dehydrogenase compared with low activity for aerobic markers citrate synthase and 3-hydroxyacetyl CoA dehydrogenase. These findings suggest that sloth forelimb muscles may rely heavily on rapid ATP resynthesis pathways, and lactate accumulation may be beneficial. The intrinsic properties observed match well with suspensory requirements, and these modifications may have further evolved in unison with low metabolism and slow movement patterns as means to systemically conserve energy.

NEW & NOTEWORTHY Myosin heavy chain (MHC) fiber type and fiber metabolic properties were evaluated to understand the ability of sloths to remain suspended for extended periods without muscle fatigue. Broad distributions of large, slow MHC-1 fibers as well as small, fast MHC-2A fibers are expressed in sloth forelimbs, but muscle metabolism is generally not correlated with myosin fiber type or body size. Sloth muscles rely on rapid, anaerobic pathways to resist fatigue and sustain force production.
Endometrial Carcinoma in a 26-Year-Old Patient with Bardet-Biedl Syndrome
Authors: Grechukhina Olga , Gressel Gregory M. , Munday William , Wong Serena , Santin Alessandro , Vash-Margita Alla
Published: May 2018

Background.Bardet-Biedl Syndrome (BBS) is a rare genetic condition characterized by cognitive impairment, dysmorphism, central obesity, and diabetes mellitus, among other abnormalities. Although some of these characteristics are known independent risk factors for endometrial cancer and its precursors, the association between BBS and endometrial cancer is underreported.Case.We present the case of a 26-year-old patient with BBS and clinical signs of hyperestrogenism who presented with abnormal uterine bleeding and was diagnosed with endometrioid adenocarcinoma. She ultimately underwent definitive surgical treatment with hysterectomy and bilateral salpingectomy.Conclusions. This is one of only a few reports in the literature describing the association of BBS and endometrioid endometrial adenocarcinoma. Given the association of BBS with risk factors for hyperestrogenism such as truncal obesity, hyperinsulinemia, and ovulatory dysfunction, providers should have increased suspicion for endometrial cancer in young patients with BBS and abnormal uterine bleeding.