33 research outputs found
Damage on masonry walls due to blast vibration
When the energy left over from a blasting process transmits to the surrounding,
particles in their paths are displaced by these waves giving rise to particle
velocities. But a structural vibration may vary according to the soil type, soil
structure interaction and characteristics of the structure.
Therefore need of a threshold, applicable to our conditions on which to base the
blasting operations was identified. This paper presents a study on investigating the
damage on wall panels due to blast vibration. A wall panel, size of 1200 mm×1000
mm with free ends and another with vertical lateral supports were constructed
closer to a rock blasting quarry and the effect of vibration on the structure was
monitored. A significant crack was observed at the foundation level of the
cantilever type wall panel at a vibration level around 30mms-1 of ppv but no
damage on the wall panel with fixed ends. Numerical modeling was carried out
with the Finite Element Modeling using SAP 2000 software. Results of the
numerical study verify that the tensile stresses of the bottom level of the wall panel
exceed the splitting tensile strength only in the wall panel with free ends
Investigation of damage on wall panels due to blast vibration
As the energy left over from a blast vibration process transmits to the surrounding, waves displace particles in their paths giving rise to particle velocities. However, the damage occurs which depends on the received structural vibration, may vary according to the soil type, soil structure interaction and characteristics of a structure. In Sri Lanka, various threshold values of blast vibration are being used although still many complains are raised on damages to structures due to blasting activities. It is necessary to understand whether all of the cracks have been induced due to the blasting activity as in some situations, the blast vibration test results were within the allowable limits.
This paper presents a study on investigating the damage on wall panels due to blast vibration. Location for the construction of the experimental model structure was selected from the initial site investigation and the vibration level measurements at different locations. The initial test carried out has shown that the soil structure interaction should be strong enough to obtain the ground vibrations. A wall panel, size of 1200 mm×1000 mm with free ends, was constructed closer to a rock blasting quarry and the effect of vibration on the structure was monitored. A significant crack was observed at the foundation level of the wall panel at a vibration level around 30mms-1 of ppv. Along with the experimental method, numerical modeling was carried out with the Finite Element Modeling using SAP 2000 software. Results of the numerical study also verify that the tensile stresses of the bottom level of the wall panel exceed the splitting tensile strength
Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018
Anemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000–2018 geospatial estimates of anemia prevalence in women of reproductive age (15–49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organization’s Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results demonstrate widespread moderate improvements in overall anemia prevalence but identify only three LMICs with a high probability of achieving the WHO GNT by 2030 at a national scale, and no LMIC is expected to achieve the target in all their subnational administrative units. Our maps show where large within-country disparities occur, as well as areas likely to fall short of the WHO GNT, offering precision public health tools so that adequate resource allocation and subsequent interventions can be targeted to the most vulnerable populations.Peer reviewe
Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018
Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950–2019: a comprehensive demographic analysis for the Global Burden of Disease Study 2019
Background: Accurate and up-to-date assessment of demographic metrics is crucial for understanding a wide range of social, economic, and public health issues that affect populations worldwide. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 produced updated and comprehensive demographic assessments of the key indicators of fertility, mortality, migration, and population for 204 countries and territories and selected subnational locations from 1950 to 2019. Methods: 8078 country-years of vital registration and sample registration data, 938 surveys, 349 censuses, and 238 other sources were identified and used to estimate age-specific fertility. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate age-specific fertility rates for 5-year age groups between ages 15 and 49 years. With extensions to age groups 10–14 and 50–54 years, the total fertility rate (TFR) was then aggregated using the estimated age-specific fertility between ages 10 and 54 years. 7417 sources were used for under-5 mortality estimation and 7355 for adult mortality. ST-GPR was used to synthesise data sources after correction for known biases. Adult mortality was measured as the probability of death between ages 15 and 60 years based on vital registration, sample registration, and sibling histories, and was also estimated using ST-GPR. HIV-free life tables were then estimated using estimates of under-5 and adult mortality rates using a relational model life table system created for GBD, which closely tracks observed age-specific mortality rates from complete vital registration when available. Independent estimates of HIV-specific mortality generated by an epidemiological analysis of HIV prevalence surveys and antenatal clinic serosurveillance and other sources were incorporated into the estimates in countries with large epidemics. Annual and single-year age estimates of net migration and population for each country and territory were generated using a Bayesian hierarchical cohort component model that analysed estimated age-specific fertility and mortality rates along with 1250 censuses and 747 population registry years. We classified location-years into seven categories on the basis of the natural rate of increase in population (calculated by subtracting the crude death rate from the crude birth rate) and the net migration rate. We computed healthy life expectancy (HALE) using years lived with disability (YLDs) per capita, life tables, and standard demographic methods. Uncertainty was propagated throughout the demographic estimation process, including fertility, mortality, and population, with 1000 draw-level estimates produced for each metric. Findings: The global TFR decreased from 2•72 (95% uncertainty interval [UI] 2•66–2•79) in 2000 to 2•31 (2•17–2•46) in 2019. Global annual livebirths increased from 134•5 million (131•5–137•8) in 2000 to a peak of 139•6 million (133•0–146•9) in 2016. Global livebirths then declined to 135•3 million (127•2–144•1) in 2019. Of the 204 countries and territories included in this study, in 2019, 102 had a TFR lower than 2•1, which is considered a good approximation of replacement-level fertility. All countries in sub-Saharan Africa had TFRs above replacement level in 2019 and accounted for 27•1% (95% UI 26•4–27•8) of global livebirths. Global life expectancy at birth increased from 67•2 years (95% UI 66•8–67•6) in 2000 to 73•5 years (72•8–74•3) in 2019. The total number of deaths increased from 50•7 million (49•5–51•9) in 2000 to 56•5 million (53•7–59•2) in 2019. Under-5 deaths declined from 9•6 million (9•1–10•3) in 2000 to 5•0 million (4•3–6•0) in 2019. Global population increased by 25•7%, from 6•2 billion (6•0–6•3) in 2000 to 7•7 billion (7•5–8•0) in 2019. In 2019, 34 countries had negative natural rates of increase; in 17 of these, the population declined because immigration was not sufficient to counteract the negative rate of decline. Globally, HALE increased from 58•6 years (56•1–60•8) in 2000 to 63•5 years (60•8–66•1) in 2019. HALE increased in 202 of 204 countries and territories between 2000 and 2019. Interpretation: Over the past 20 years, fertility rates have been dropping steadily and life expectancy has been increasing, with few exceptions. Much of this change follows historical patterns linking social and economic determinants, such as those captured by the GBD Socio-demographic Index, with demographic outcomes. More recently, several countries have experienced a combination of low fertility and stagnating improvement in mortality rates, pushing more populations into the late stages of the demographic transition. Tracking demographic change and the emergence of new patterns will be essential for global health monitoring. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens
Global burden of 87 risk factors in 204 countries and territories, 1990�2019: a systematic analysis for the Global Burden of Disease Study 2019
Background: Rigorous analysis of levels and trends in exposure to leading risk factors and quantification of their effect on human health are important to identify where public health is making progress and in which cases current efforts are inadequate. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 provides a standardised and comprehensive assessment of the magnitude of risk factor exposure, relative risk, and attributable burden of disease. Methods: GBD 2019 estimated attributable mortality, years of life lost (YLLs), years of life lived with disability (YLDs), and disability-adjusted life-years (DALYs) for 87 risk factors and combinations of risk factors, at the global level, regionally, and for 204 countries and territories. GBD uses a hierarchical list of risk factors so that specific risk factors (eg, sodium intake), and related aggregates (eg, diet quality), are both evaluated. This method has six analytical steps. (1) We included 560 risk�outcome pairs that met criteria for convincing or probable evidence on the basis of research studies. 12 risk�outcome pairs included in GBD 2017 no longer met inclusion criteria and 47 risk�outcome pairs for risks already included in GBD 2017 were added based on new evidence. (2) Relative risks were estimated as a function of exposure based on published systematic reviews, 81 systematic reviews done for GBD 2019, and meta-regression. (3) Levels of exposure in each age-sex-location-year included in the study were estimated based on all available data sources using spatiotemporal Gaussian process regression, DisMod-MR 2.1, a Bayesian meta-regression method, or alternative methods. (4) We determined, from published trials or cohort studies, the level of exposure associated with minimum risk, called the theoretical minimum risk exposure level. (5) Attributable deaths, YLLs, YLDs, and DALYs were computed by multiplying population attributable fractions (PAFs) by the relevant outcome quantity for each age-sex-location-year. (6) PAFs and attributable burden for combinations of risk factors were estimated taking into account mediation of different risk factors through other risk factors. Across all six analytical steps, 30 652 distinct data sources were used in the analysis. Uncertainty in each step of the analysis was propagated into the final estimates of attributable burden. Exposure levels for dichotomous, polytomous, and continuous risk factors were summarised with use of the summary exposure value to facilitate comparisons over time, across location, and across risks. Because the entire time series from 1990 to 2019 has been re-estimated with use of consistent data and methods, these results supersede previously published GBD estimates of attributable burden. Findings: The largest declines in risk exposure from 2010 to 2019 were among a set of risks that are strongly linked to social and economic development, including household air pollution; unsafe water, sanitation, and handwashing; and child growth failure. Global declines also occurred for tobacco smoking and lead exposure. The largest increases in risk exposure were for ambient particulate matter pollution, drug use, high fasting plasma glucose, and high body-mass index. In 2019, the leading Level 2 risk factor globally for attributable deaths was high systolic blood pressure, which accounted for 10·8 million (95 uncertainty interval UI 9·51�12·1) deaths (19·2% 16·9�21·3 of all deaths in 2019), followed by tobacco (smoked, second-hand, and chewing), which accounted for 8·71 million (8·12�9·31) deaths (15·4% 14·6�16·2 of all deaths in 2019). The leading Level 2 risk factor for attributable DALYs globally in 2019 was child and maternal malnutrition, which largely affects health in the youngest age groups and accounted for 295 million (253�350) DALYs (11·6% 10·3�13·1 of all global DALYs that year). The risk factor burden varied considerably in 2019 between age groups and locations. Among children aged 0�9 years, the three leading detailed risk factors for attributable DALYs were all related to malnutrition. Iron deficiency was the leading risk factor for those aged 10�24 years, alcohol use for those aged 25�49 years, and high systolic blood pressure for those aged 50�74 years and 75 years and older. Interpretation: Overall, the record for reducing exposure to harmful risks over the past three decades is poor. Success with reducing smoking and lead exposure through regulatory policy might point the way for a stronger role for public policy on other risks in addition to continued efforts to provide information on risk factor harm to the general public. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens
The global burden of cancer attributable to risk factors, 2010–19: a systematic analysis for the Global Burden of Disease Study 2019
BACKGROUND: Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. METHODS: The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk–outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. FINDINGS: Globally, in 2019, the risk factors included in this analysis accounted for 4·45 million (95% uncertainty interval 4·01–4·94) deaths and 105 million (95·0–116) DALYs for both sexes combined, representing 44·4% (41·3–48·4) of all cancer deaths and 42·0% (39·1–45·6) of all DALYs. There were 2·88 million (2·60–3·18) risk-attributable cancer deaths in males (50·6% [47·8–54·1] of all male cancer deaths) and 1·58 million (1·36–1·84) risk-attributable cancer deaths in females (36·3% [32·5–41·3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20·4% (12·6–28·4) and DALYs by 16·8% (8·8–25·0), with the greatest percentage increase in metabolic risks (34·7% [27·9–42·8] and 33·3% [25·8–42·0]). INTERPRETATION: The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
Applying Tikhonov regularization to the time-concentration data of reaction kinetics
[Extract] Experimental data of reaction kinetics are usually in the form of concentration or mole fraction versus time. For kinetic investigation, such as determination of the appropriate\ud
reaction rate expression, it is more convenient to have the data in the form of reaction rate versus concentration. Converting time-concentration data into concentration reaction rate data by direct numerical differentiation of experimental kinetic data will amplify the noise in the data leading to unreliable results [I]. This paper describes a conversion procedure in which the differentiation process is replaced by one of solving an integral equation of the first\ud
kind. The integral equation is then solved by Tikhonov regularization a well-proven method for handling this class of equations [I]. This procedure leads to a smooth concentration reaction rate curve that is independent of kinetic model and manages to keep noise amplification under control.\ud
\ud
The performance of this procedure is demonstrated by applying it to kinetic data taken from the published literature. Since these data are accompanied by their rate expressions, the\ud
computed rates are used to obtain the unknown parameters in these expressions. Comparison of the results with published figures and the ease with which they are obtained highlight the\ud
advantages of the new procedure. Where necessary the rate expression is modified and new/additional parameters are obtained. This fin al step shows the flexib ility of Tikhonov\ud
regularization as a general tool for investigating alternative kinetic models
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Responsive Membranes and Materials
Preface xv List of Contributors xxi 1 Oligonucleic Acids ("Aptamers") for Designing Stimuli-Responsive Membranes 1 Veli Cengiz Ö zalp, Maŕýa Beleń Serrano-Santos and Thomas Schäfer 1.1 Introduction 1 1.2 Aptamers - Structure, Function, Incorporation, and Selection 4 1.3 Characterization Techniques for Aptamer-Target Interactions 7 1.3.1 Measuring Overall Structural Changes of Aptamers Using QCM-D 8 1.3.2 Measuring Overall Structural Changes of Aptamers Using DPI 13 1.4 Aptamers - Applications 17 1.4.1 Electromechanical Gates 17 1.4.2 Stimuli-Responsive Nucleic Acid Gates in Nanoparticles 17 1.4.3 Stimuli-Responsive Aptamer Gates in Nanoparticles 20 1.4.4 Stimuli-Responsive Aptamer-Based Gating Membranes 22 1.5 Outlook 25 Acknowledgements 26 References 26 2 Emerging Membrane Nanomaterials - Towards Natural Selection of Functions 31 Mihail Barboiu 2.1 Introduction 31 2.2 Ion-Pair Conduction Pathways in Liquid and Hybrid Membranes 32 2.3 Dynamic Insidepore Resolution Towards Emergent Membrane Functions 36 2.4 Dynameric Membranes and Materials 39 2.4.1 Constitutional Hybrid Materials 39 2.4.2 Dynameric Membranes Displaying Tunable Properties on Constitutional Exchange 41 2.5 Conclusion 46 Acknowledgements 47 References 47 3 Carbon Nanotube Membranes as an Idealized Platform for Protein Channel Mimetic Pumps 51 Bruce Hinds 3.1 Introduction 51 3.2 Experimental Understanding of Mass Transport Through CNTs 56 3.2.1 Ionic Diffusion and Gatekeeper Activity 57 3.2.2 Gas and Fluid Flow 57 3.3 Electrostatic Gatekeeping and Electro-osmotic Pumping 59 3.3.1 Biological Gating 62 3.4 CNT Membrane Applications 63 3.5 Conclusion and Future Prospects 66 Acknowledgements 67 References 67 4 Synthesis Aspects in the Design of Responsive Membranes 73 Scott M. Husson 4.1 Introduction 73
4.2 Responsive Mechanisms 74 4.3 Responsive Polymers 75 4.3.1 Temperature-Responsive Polymers 75 4.3.2 Polymers that Respond to pH, Ionic Strength, Light 76 4.4 Preparation of Responsive Membranes 77 4.5 Polymer Processing into Membranes 78 4.5.1 Solvent Casting 78 4.5.2 Phase Inversion 78 4.6 In Situ Polymerization 78 4.6.1 Radiation-Based Methods 78 4.6.2 Interpenetrating Polymer Networks (IPNs) 79 4.7 Surface Modification Using Stimuli-Responsive Polymers 79 4.8 "Grafting to" Methods 81 4.8.1 Physical Adsorption - Non-covalent 81 4.8.2 Chemical Grafting - Covalent 81 4.8.3 Surface Entrapment - Non-covalent, Physically Entangled 82 4.9 "Grafting from" - a.k.a. Surface-Initiated Polymerization 83 4.9.1 Photo-Initiated Polymerization 83 4.9.2 Atom Transfer Radical Polymerization 85 4.9.3 Reversible Addition-Fragmentation Chain Transfer Polymerization 87 4.9.4 Other Grafting Methods 91 4.9.5 Summary of "Grafting from" Methods 91 4.10 Future Directions 91 References 92 5 Tunable Separations, Reactions, and Nanoparticle Synthesis in Functionalized Membranes 97 Scott R. Lewis, Vasile Smuleac, Li Xiao and D. Bhattacharyya 5.1 Introduction 97 5.2 Membrane Functionalization 98 5.2.1 Chemical Modification 98 5.2.2 Surface Initiated Membrane Modification 101 5.2.3 Cross-Linked Hydrogel (Pore Filled) Membranes 102 5.2.4 Layer by Layer Assemblies 103 5.3 Applications 104 5.3.1 Water Flux Tunability 104 5.3.2 Tunable Separation of Salts 109 5.3.3 Charged-Polymer Multilayer Assemblies for Environmental Applications 113 5.4 Responsive Membranes and Materials for Catalysis and Reactions 115 5.4.1 Iron-Functionalized Responsive Membranes 116 5.4.2 Responsive Membranes for Enzymatic Catalysis 127 Acknowledgements 132 References 132 6 Responsive Membranes for Water Treatment 143 Qian
Yang and S. R. Wickramasinghe 6.1 Introduction 143 6.2 Fabrication of Responsive Membranes 144 6.2.1 Functionalization by Incubation in Liquids 145 6.2.2 Functionalization by Incorporation of Responsive Groups in the Base Membrane 145 6.2.3 Surface Modification of Existing Membranes 148 6.3 Outlook 158 References 159 7 Functionalization of Polymeric Membranes and Feed Spacers for Fouling Control in Drinking Water Treatment Applications 163 Colleen Gorey, Richard Hausman and Isabel C. Escobar 7.1 Membrane Filtration 163 7.2 Fouling 165 7.3 Improving Membrane Performance 168 7.3.1 Plasma Treatment 168 7.3.2 Ultraviolet (UV) Irradiation 170 7.3.3 Membrane Modification by Graft Polymerization 171 7.3.4 Ion Beam Irradiation 176 7.4 Design and Surface Modifications of Feed Spacers for Biofouling Control 178 7.5 Conclusion 180 Acknowledgements 181 References 181 8 Pore-Filled Membranes as Responsive Release Devices 187 Kang Hu and James Dickson 8.1 Introduction 187 8.2 Responsive Pore-Filled Membranes 188 8.3 Development and Characterization of PVDF-PAA Pore-Filled pH-Sensitive Membranes 190 8.3.1 Membrane Gel Incorporation (Mass Gain) 191 8.3.2 Membrane pH Reversibility 191 8.3.3 Membrane Water Flux as pH Varied from 2 to 7.5 191 8.3.4 Effects of Gel Incorporation on Membrane Pure Water Permeabilities at pH Neutral and Acidic 195 8.3.5 Estimation and Calculation of Pore Size 198 8.4 pH-Sensitive Poly(Vinylidene Fluoride)-Poly(Acrylic Acid) Pore-Filled Membranes for Controlled Drug Release in Ruminant Animals 201 8.4.1 Determination of Membrane Diffusion Permeability (PS) for Salicylic Acid 202 8.4.2 Applicability of the Fabricated Pore-Filled Membranes on the Salicylic Acid Release and Retention 205 References 207 9 Magnetic Nanocomposites for Remote Controlled Responsive Therapy and in
Vivo Tracking 211 Ashley M. Hawkins, David A. Puleo and J. Zach Hilt 9.1 Introduction 211 9.1.1 Nanocomposite Polymers 211 9.1.2 Magnetic Nanoparticles 212 9.2 Applications of Magnetic Nanocomposite Polymers 212 9.2.1 Thermal Actuation 213 9.2.2 Thermal Therapy 218 9.2.3 Mechanical Actuation 220 9.2.4 In Vivo Tracking and Applications 224 9.3 Concluding Remarks 224 References 224 10 The Interactions between Salt Ions and Thermo-Responsive Poly (N-Isopropylacrylamide) from Molecular Dynamics Simulations 229 Hongbo Du and Xianghong Qian 10.1 Introduction 229 10.2 Computational Details 230 10.3 Results and Discussion 232 10.4 Conclusion 238 Acknowledgements 240 References 240 11 Biologically-Inspired Responsive Materials: Integrating Biological Function into Synthetic Materials 243 Kendrick Turner, Santosh Khatwani and Sylvia Daunert 11.1 Introduction 243 11.2 Biomimetics in Biotechnology 245 11.3 Hinge-Motion Binding Proteins 249 11.4 Calmodulin 250 11.5 Biologically-Inspired Responsive Membranes 251 11.6 Stimuli-Responsive Hydrogels 253 11.7 Micro/Nanofabrication of Hydrogels 255 11.8 Mechanical Characterization of Hydrogels 256 11.9 Creep Properties of Hydrogels 257 11.10 Conclusion and Future Perspectives 258 Acknowledgements 258 References 258 12 Responsive Colloids with Controlled Topology 269 Jeffrey C. Gaulding, Emily S. Herman and L. Andrew Lyon 12.1 Introduction 269 12.2 Inert Core/Responsive Shell Particles 270 12.3 Responsive Core/Responsive Shell Particles 275 12.4 Hollow Particles 281 12.5 Janus Particles 286 12.6 Summary 292 References 293 13 Novel Biomimetic Polymer Gels Exhibiting Self-Oscillation 301 Ryo Yoshida 13.1 Introduction 301 13.2 The Design Concept of Self-Oscillating Gel 303 13.3 Aspects of the Autonomous Swelling-Deswelling Oscillation 303
13.4 Design of Biomimetic Actuator Using Self-Oscillating Polymer and Gel 306 13.4.1 Ciliary Motion Actuator (Artificial Cilia) 306 13.4.2 Self-Walking Gel 307 13.4.3 Theoretical Simulation of the Self-Oscillating Gel 307 13.5 Mass Transport Surface Utilizing Peristaltic Motion of Gel 308 13.6 Self-Oscillating Polymer Chains and Microgels as "Nanooscillators" 309 13.6.1 Solubility Oscillation of Polymer Chains 309 13.6.2 Self-Flocculating/Dispersing Oscillation of Microgels 310 13.6.3 Viscosity Oscillation of Polymer Solution and Microgel Dispersion 311 13.6.4 Attempts of Self-Oscillation under Acid- and Oxidant-Free Physiological Conditions 311 13.7 Conclusion 312 References 312 14 Electroactive Polymer Soft Material Based on Dielectric Elastomer 315 Liwu Liu, Zhen Zhang, Yanju Liu and Jinsong Leng 14.1 Introduction to Electroactive Polymers 315 14.1.1 Development History 316 14.1.2 Classification 316 14.1.3 Electronic Electroactive Polymers 316 14.1.4 Ionic Electroactive Polymers 318 14.1.5 Electroactive Polymer Applications 318 14.1.6 Application of Dielectric Elastomers 318 14.1.7 Manufacturing the Main Structure of Actuators Using EAP Materials 327 14.1.8 The Current Problem for EAP Materials and their Prospects 329 14.2 Materials of Dielectric Elastomers 330 14.2.1 The Working Principle of Dielectric Elastomers 330 14.2.2 Material Modification of Dielectric Elastomer 331 14.2.3 Dielectric Elastomer Composite 334 14.3 The Theory of Dielectric Elastomers 336 14.3.1 Free Energy of Dielectric Elastomer Electromechanical Coupling System 336 14.3.2 Special Elastic Energy 339 14.3.3 Special Electric Field Energy 341 14.3.4 Incompressible Dielectric Elastomer 342 14.3.5 Model of Several Dielectric Elastomers 342 14.4 Failure Model of a Dielectric Elastomer 356 14.4.1 Electrical
Breakdown