bluuebunny/crossref_metadata_2025 huggingface dataset:
Making Ourselves Visible: Mobilizing Micro-Autoethnography in the Study of Self-Representation and Interface Affordances
Authors: McArthur Victoria
Published: March 2019

Avatar customization and self-representation in games has been widely studied. In this paper, I propose the use of micro-autoethnography as a complementary methodology in such studies. I propose such an approach, theoretically and methodologically informed by Actor-Network Theory, as a way for researchers to situate themselves within their own studies of identity and play in games. I present a micro-autoethnographic study in which I, the researcher, attempt to create the same avatar in eight different Character Creation Interfaces (CCIs), otherwise known as a "trans-ludic" avatar. Implications for a micro-autoethnographic approach to avatar and identity research are discussed.
The clandestine cemetery
Authors: Zagaria Valentina
Published: March 2019

The Mediterranean Sea has recently become the deadliest of borders for
illegalised travellers. The victims of the European Union’s liquid border
are also found near North African shores. The question of how and where to bury
these unknown persons has recently come to the fore in Zarzis, a coastal town in
south-east Tunisia. Everyone involved in these burials – the coastguards,
doctors, Red Crescent volunteers, municipality employees – agree that
what they are doing is ‘wrong’. It is neither dignified nor
respectful to the dead, as the land used as a cemetery is an old waste dump, and
customary attitudes towards the dead are difficult to realise. This article will
first trace how this situation developed, despite the psychological discomfort
of all those affected. It will then explore how the work of care and dignity
emerges within this institutional chain, and what this may tell us about what
constitutes the concept of the human.
Unmanned Aerial Vehicle Surveying For Monitoring Road Construction Earthworks
Authors: Julge Kalev , Ellmann Artu , Köök Romet
Published: March 2019

Unmanned aerial vehicle photogrammetry is a surveying technique that enables generating point clouds, 3D surface models and orthophoto mosaics. These are based on photos captured with a camera placed on an unmanned aerial vehicle. Within the framework of this research, unmanned aerial vehicle photogrammetry surveys were carried out over a sand and gravel embankment with the aim of assessing the vertical accuracy of the derived surface models. Flight altitudes, ground control points and cameras were varied, and the impact of various factors on the results was monitored. In addition, the traditional real-time-kinematic Global Navigation Satellite System surveys were conducted for verifications. Surface models acquired by different methods were used to calculate volumes and compare the results with requirements set by Estonian Road Administration. It was found that with proper measuring techniques an accuracy of 5.7 cm for the heights were achieved.
Creep Characteristics Of Concrete Used In Long-Span Arch Bridge
Authors: Wang Yongbao , Zhao Renda , Jia Yi , Liao Ping
Published: March 2019

The reinforced concrete arch bridge with concrete-filled steel tubular stiffened skeleton is extensively used in the mountainous area of southwest China due to their long span and high stability. Beibanjiang Bridge located in Shanghai- Kunming high-speed railway, which had a record span of 445 m, has recently been completed in 2016. However, concrete creep and shrinkage have pronounced effects on the long-term deflection and stress redistribution of this bridge. Several concrete creep and shrinkage specimens in the natural environment were made to predict the long-term behaviour of this bridge accurately. They were used to measure the concrete creep and shrinkage of the core concrete and surrounding concrete used in the arch bridge. The test results were compared to ACI209 R-92 Prediction of Creep, Shrinkage and Temperature Effects in Concrete Structures model, 1990 CEB-FIP Model Code 1990: Design Code model, fib Model Code for Concrete Structures 2010 model and Creep and Shrinkage Prediction Model for Analysis and Design of Concrete Structures-Model B3. Based on the numerical fitting method, the fib Model Code for Concrete Structures 2010 model was modified to suit the concrete creep and shrinkage experimental results. Then, the modified fib Model Code for Concrete Structures 2010 model was used to predict the timedependent behaviour of a concrete arch bridge.
Assessment Of Designed And Measured Mechanistic Parameters Of Concrete Pavement Foundation
Authors: Zhang Yang , Vennapusa Pavana , White David Joshua
Published: March 2019

There are plenty of in situ tests available to examine pavement foundation performance regarding stiffness and support conditions. This study evaluates several in situ tests of the stiffness and support conditions of concrete pavement foundation layers. The principal objective of this study was to evaluate the outputs from Dynamic Cone Penetrometer tests and Falling Weight Deflectometer tests. The California Bearing Ratio from Dynamic Cone Penetrometer tests and the deflection data from Falling Weight Deflectometer tests were correlated to the design parameter – modulus of subgrade reaction k through correlations employed in pavement design manuals. Three methods for obtaining the k values were conducted, with the intent to evaluate which method provides the results most similar to the target value and whether the studied correlations are reliable. The back-calculated k values from Falling Weight Deflectometer deflections and the weak layer California Bearing Ratio correlated k values based on the Portland Cement Association method were close to the target value, while the California Bearing Ratio empirically correlated k based on the American Association of State Highway and Transportation Officials method presented values significantly higher than the target value. Those previously reported correlations were likely to overestimate the k values based on subgrade California Bearing Ratio values.
Methodology For Determining Reliable Traffic Parameters For Current Analysis Of Performance Of Motorways And Expressways
Authors: Spławińska Malwina
Published: March 2019

In this paper, the results of analyses concerning selected traffic characteristics typical for Polish motorways and expressways are presented. The input data were collected automatically by stations located on various highways. In the first place, with the use of the coefficient of variability, periods with the lowest traffic volume variability in the year and the day were determined. On this basis, the most favourable time scope of random measurements was determined to allow reliable estimation of traffic parameters for road performance analyses. Then, based on model relationships between the characteristics of traffic volume variability over time and constant volume (regression relationships, a model of Artificial Neural Networks), correction factors were developed enabling direct conversion of the obtained measurement results into Design Hourly Volume. In addition, the rules for determining the share of heavy vehicles meeting the conditions at peak hours of the year were developed. The presented approach is in line with the current research trend on a global scale and allows for improving the accuracy of estimating Design Hourly Volume by 20 per cent concerning the method currently recommended in Poland.
Differentiation potential to neural-like cells in human adrenocortical carcinoma SW-13 cells
Authors: Shimada Eriko , Tsuruwaka Yusuke
Published: March 2019

Various cancer cells are known to show neural differentiation. Adrenocortical carcinoma (ACC) is a rare and frequently aggressive tumor originating in the cortex of the adrenal gland. Early diagnosis of ACC is challenging due to a lot of unknown aspects such as cell characteristics in a rare cancer. In the present study, morphological features were examined in the adrenal cortex carcinoma cells SW-13 as an initial candidate, which were exposed to neural differentiation condition. SW-13 cells treated with the neural induction supplement showed neural-like differentiation with elongated filaments. It was suggested that SW-13 cells had neural differentiation potential and could be a research tool to elucidate the cell characteristics in future ACC studies.
New fracking method of reservoir rocks: a “green” technology
Authors: Cataldi Raffaele
Published: March 2019

not available
Current approaches to rehoming unwanted, escaped and seized native animal pets in New South Wales and recent trends
Authors: Mo Matthew , Oliver Robert
Published: March 2019

Native mammals, birds, reptiles and frogs kept as pets become displaced after they are unwanted, escaped or seized. The Office of Environment and Heritage manages the rehoming of displaced native animal pets, which are regulated under the Biodiversity Conservation Act 2016 in New South Wales. Primarily, animals are balloted to licensed animal keepers and exhibitors. Otherwise, rehoming may be delegated to third party organisations, and pet shops licensed to sell reptiles are obligated to accept back returned reptiles for resale. From 2014 to 2017, at least 1,000 native animal pets were rehomed in New South Wales, the majority of which were reptiles. During this period, there was a significant increase in annual numbers of displaced native animal pets related to a recent increase in displaced reptiles. The majority of cases occurred within the Greater Sydney region. The trends presented in this paper had important implications for a review of the current management framework in light of the increasing volumes. Initial stakeholder consultations have supported the notion of a community education program with an emphasis on responsible pet ownership.
Inhibition of Fe2+ Induced Lipid Peroxidation in Rats Brain by Extract of Euphorbia heterophylla in vitro
Authors: Babatola Leye Jonathan , B. Oshanimi Oluwakemisola , M. Oluba Olanrewaju , Okoror Lawrence , Odutuga Adewale Agboola
Published: March 2019

This study is sought to determine the antioxidant activity and protective ability of aqueous and methanol extractible phytochemicals from Euphorbia heterophylla leaves on lipid peroxidation induced in rat brain by pro-oxidant, in vitro. The extracts of the leaves were prepared, and the ability of the extracts is to inhibit 25 µM FeSO4 induced lipid peroxidation in isolated rats’ brain, were determined. Thereafter, total phenol content, reducing power (FRAP), Fe (II) chelating, and DPPH* free radical scavenging ability of the extracts was determined and considered as an index of antioxidant activity. The results revealed that the extracts inhibit malondialdehyde (MDA) production in the basal and pro-oxidant induced lipid peroxidised rats in a dose-dependent manner, [methanol 80.11%, aqueous 70.3%] with the methanol extract (MEE) significantly (P< 0.05) than that of aqueous extract (AEE). The methanol extract (0.74 ± 0.6 mg/g) had higher total phenol contents than the aqueous (0.57 ± 1.2 mg/g); likewise the methanol extract had higher reducing power (0.08 ± 0.2, 0.03 ± 0.1 mg/g), but had no significant difference in Fe (II) chelating ability (EC50= 0.34, 0.36) with DPPH* scavenging ability (EC50=0.075, 0.075). This antioxidant properties and the protective effect of this leaf could be harnessed in the management and prevention of degenerative diseases in association with oxidative stress.
Universal Computing Machine for Number Genetics in the Proportiones Perfectus Theory
Authors: Mamombe Lovemore
Published: March 2019

The proportiones perfectus law states that σ_x^y=(x+√(x^2+4y))/2 is a proportione perfectus if 1≤y≤x such that for an arbitrary positive integer , there exists an integer sequence defined simultaneously by the quasigeometric relation h_(n+1)=round(σ_x^y h_n ),n≥1 and the arithmetic relation h_(n+2)=〖xh〗_(n+1)+〖yh〗_n,n≥1.        When x=y=1 σ_x^y  is the golden mean. When x=2,y=1,σ_x^y  is the silver mean. In previous works we introduced the theory of number genetics – a framework of logic within which the golden section is studied. In this work we apply the concept to all proportiones perfectus. Let  be defined as above. Furthermore, let h1 satisfy {█(round(h_1/(σ_x^y ))=w@round(wσ_x^y)≠h_1 ). ┤Now let H'nbe Hn  with h1=1 Again let  be defined as  A robust universal computing machine is herein developed for the purpose of establishing the relationship  h_i=g_(n+i-1)±h_i^',i,n≥1,  which relationship is key to the logic protocol. It is clear therefore that this system of logic presents  as the building block of every  (including itself) within a particular σ_x^y regime. Clearly number genetics takes central place in the proportiones perfectus theory.
Cross-Generation and Cross-Country Evidence on the Link between Growth and Volatility
Authors: Edgeweblime Kcodgoh L.
Published: March 2019

This paper reports on a larger scale econometric study of the sign of the relationship between average growth and growth volatility of GDP per capita. At equilibrium, the negativity or the positivity of the relationship between endogenous growth and business cycles volatility is linked to the movements (left or right side) of (PPF). Tests have focused on cross-generation and cross-country evidence on the link between growth and volatility. If production possibilities frontier movements’ trend is to the left side, countries with a higher standard deviation of growth should have their growth adversely affected if at the same time they lose their comparative advantages. Thus international trade elasticity after a production possibilities frontier movement (ei) determines the sign of the relationship between growth and volatility. If (ei -1) < 0, the sign is negative and positive if (ei – 1) > 0. From the theoretical point of view, a new multidimensional trade and optimal growth mechanisms have been presented.
Corporate Social and Environmental Reporting (CSER) and Financial Performance: The Mediating Role of Competitive Advantage
Authors: Orakwue Amaka Chinanu , Oghuvwu Martha Evi
Published: March 2019

The paper examined the mediating effect of competitive advantage on the relationship between CSER and financial performance in Nigeria. The study adopted the ex-post causal research design because it seeks to examine the causality between CSER and financial performance within a mediation context. A sample size of 100 companies from all sectors listed on the Nigerian Stock exchange (NSE) between 2007 and 2016 was used. Panel regression analysis was used in the estimation of the data. The mediation Model was tested based on Baron and Kenny’s (1986) conditions for mediation. Results from the study revealed that competitive advantage mediates in the relationship between CSER and financial performance. This result confirms the Resource Based Theory (RBT) that engaging in social and environmental reporting activities can enhance a company’s competitive advantage which will ultimately improve the financial performance in Nigeria. The study recommends that corporations in developing and emerging markets should begin to think differently about CSER as a proactive and strategic tool towards enhancing competitive advantage and consequently financial performance rather than just in response to the demand for CSER globally.
Why are Narratives that Place the Blame for Deforestation on the Rural Poor so Pervasive and so Persistent?
Authors: Rai Jeetesh
Published: March 2019

Deforestation is a prominent issue in the call for global environmental sustainability whose status transcends the realm of environmental studies and extends to the broader domains of public policy and popular concern. Deforestation issues are complex, and narratives provide the simple explanations needed by policymakers and the public. One of the most common narratives explaining deforestation places the blame on the rural poor. These narratives make facile connections between the poor who depend on the forests for their livelihood and the environmental degradation which is taking place in their immediate vicinity. They unite two major problems in a neat hermeneutic circle: the rural poor are caught in a vicious cycle of poverty and environmental degradation, where they are both the victims and the perpetrators. While rural poverty and deforestation are closely connected, the relationship is a complex one - contrary to what such simple narratives lead us to believe - and the causes of deforestation remain unclear. This article discusses the causes that explain why are narratives that place the blame for deforestation on the rural poor so pervasive and so persistent?
Phytochemical Composition of Aqueous and Ethanolic Leaf Extracts of Piper guineense, Cassia alata, Tagetes erecta and Ocimum graticimum
Authors: Amadioha A. C. , Chidi Kenkwo Promise
Published: March 2019

Phytochemicals are biologically active naturally occurring chemicals produced by plants to help them thrive or thwart competitors or pathogenic organisms. The phytochemical experiment revealed varying degrees of flavonoid, alkaloid, saponin, tanin and phenol as naturally occurring bioactive chemicals of water and ethanol leaf extracts of Piper guineense, Cassia alata, Tagetes erecta and Ocimum graticimum. T. erecta had the highest flavonoid, alkaloid, saponin and tanin content of 3.17%, 5.43%, 3.50% and 5.15% respectively in ethanol extract and this was significant (P≤ 0.05), and followed by C. alata, O. graticimum, and P. guineense. The highest phenol content of 3.50% was recorded in water extract of C. alata followed by water extract of T. erecta, O. graticimum, and ethanol extract of P. guineense. The exploitation of antimicrobial potentials of these phytochemicals in the control of plant diseases incited by pathogenic organisms is recommended.
Therapeutic Landscapes
Authors: Williams Allison M.
Published: March 2019

The concept of therapeutic landscape is recognized as one of the key contributions that geographers have made to the study of health. It is an essentially metaphorical concept that continues to evolve, with innovative applications, to better understand the characteristics of place that contribute to the processes at play in the making of healing places and symbolic landscapes, and in the marketing of such places.
Time–Space Convergence
Authors: Janelle Donald G.
Published: March 2019

Innovations in transportation, communication, and information technologies are primary means for allocating accessibility among places and regions. Time–space convergence provides a measurement framework for documenting variations in the distribution of accessibility and offers a basis for conceptualizing the implications of such variation for the organization and use of space at personal, local, regional, and global scales.
Rights, Labor
Authors: Doucette Jamie
Published: March 2019

Labor rights include geographically limited normative and legal rights, universal human rights that pertain to labor relations between workers and their employers, and the collective rights of workers within society; the latter are presumed to be geographically and politically universal but in practice they are unevenly distributed and exercised. In capitalist economies, the collective nature of such rights creates tension with existing property rights; nonetheless, the exercise of labor rights remains an important aspect of the pursuit of social justice. In order to better understand how labor rights have been unevenly recognized and exercised across geographic space, recent scholarship has examined how labor rights are configured through diverse sociospatial registers, including global production networks, national territories, and geographic scale, as well as practices of migration.
Environment and Waste
Authors: Barr Stewart
Published: March 2019

This entry explores the emergence of one of the most iconic aspects of environmental management in the late twentieth and early twenty‐first centuries: the challenge of dealing with “waste” in consumption‐based societies. Linked to broader social and political discourses on the environment, understanding, defining, and dealing with waste have become a preoccupation for researchers and governments seeking to address a range of environmental goals. This entry will examine the emergence of waste as a sociopolitical discourse and will situate waste within the context of broader political ecologies in developed nations. The entry will then examine the key intellectual approaches that researchers have developed to examine the challenge of waste management before examining the policy responses to what many have termed the “throwaway society.”
Environmental (In)Security
Authors: Dalby Simon
Published: March 2019

Human insecurity is a matter of both environmental and social circumstances. In recent decades concerns with environmental change and its possible impacts on human societies have been linked to policy discussions of security. Scholarly analyses of resources, environment, change, and conflict suggest that these are far from simple linkages; scarcities and abundant resources are related to conflict but in complex ways. Discussions of the collapse of civilizations and alarm about such things as water wars now connect academic research, policy discussion, and media to the extensive discussion of climate change. This has rekindled scholarly debates from the 1990s and added urgency to policy deliberations about environmental security now that it is increasingly clear that humankind is substantially altering the Earth system.
Internationalization
Authors: Ström Patrik
Published: March 2019

Internationalization is a vital part of the world economy. It is the process that helps to connect places and firms. It can be based on macro‐economic dimensions in relation to the spatial configuration of activities, but it is also connected to the locational strategy of firms. Internationalization is examined from a range of different perspectives with a focus on how it can be interpreted and what it means for the spatial dynamics of the world economy.
Climate Change and Sea Ice
Authors: Comiso Josefino C.
Published: March 2019

Global warming signals are observed in the atmosphere, land, ocean, and ice from multiple instrumental and paleoclimatic sources. Data indicate regional warming and changes in precipitation patterns. The heat content of the ocean up to 700 m in depth has increased significantly while the contrast between wet regions and dry regions over the oceans has increased over the past 60 years. Among the strongest signals of warming are those from polar regions where climate change is amplified and increases in temperature have caused significant changes in the timing of the melt season, retreats in the snow cover, loss of mass in ice sheet and glaciers, and thawing of the permafrost. But among the most dramatic changes observed on a global scale have been the rapid decline of the perennial and multiyear ice cover in the Arctic during the period 1979–2017. Such decline can cause profound changes in the Arctic environment and the Earth's climate system.
Financialization
Authors: Aalbers Manuel B.
Published: March 2019

This entry explains the rising popularity of the concept of financialization, despite it being considered a vague and chaotic concept. It also summarizes the wide‐ranging multidisciplinary literature on financialization and makes a distinction between seven dimensions, or elements, of financialization, upon which a new definition of financialization is put forward that suggests that the power of the financialization literature lies in how it tries to understand the increasing dominance of financial actors, markets, practices, measurements, and narratives at various scales, resulting in a structural transformation of economies, firms (including financial institutions), states, and households. In discussing the different elements of financialization, the entry focuses on the financialization of the economy, nonfinancial firms, the state, and households, but also on the processes of banking disintermediation and assetization. Finally, some avenues for future research are suggested.
Environment and Health
Authors: Elliott Susan J.
Published: March 2019

The study of links between environment and health involves examination of those aspects of human health influenced by the physical, social, biological, psychosocial, chemical, economic, political, and cultural environments within which we live, work, and play. Examples abound: the disappearance of the Aral Sea, a fourfold increase in asthma since the mid‐1990s, widespread water‐related illness in the developed world (e.g., Walkerton in Canada, in 2000; Flint, Michigan, in the United States, 2017–present), a doubling of the prevalence of peanut allergy, such high demands for energy that we imperil human safety through the proliferation of nuclear power, which leads to the potential for the proliferation of nuclear weapons in unstable nation‐states. This situation is punctuated by the occurrence of major environmental disasters (Love Canal, Bhopal, Chernobyl). Ongoing concerns about creeping environmental disasters (e.g., the health impacts of global climate change) keep environment and health issues on the front pages of newspapers and at the top of research agendas. The complexity of designing studies that answer targeted questions remains a challenge; and, yet, decisions must be made with respect to policy, regulations, and guidelines designed to protect the health of the public.
Oral History and Narrative
Authors: Stratford Elaine
Published: March 2019

Among diverse peoples and cultures, the need to hear and be heard, the urge to remember, reflect, and communicate, and the compulsion to understand the world will often gather as a combined force and show up in our lives as storytelling and narrative. As a sapient species, it is through language that we learn meta‐awareness – awareness of ourselves and other entities. We speak ourselves into existence, if you like. Thus, oral history is a powerful qualitative research method to directly engage with those who are still living and help preserve their memories, stories, and knowledges while they live and after their deaths. Using such field methods, practitioners seek to understand participants' experiences of the lifeworld: ways of being, in place and on the move, over the whole life course. Practitioners of oral history are also concerned to understand how participants' experiences reveal and illuminate other issues and events which, in the past, may have been remarkable or may have seemed quite mundane. Oral history's capacity to uncover the extraordinary that resides within the everyday empowers both participants and readers or audiences of oral histories. This method also enables practitioners – geographers among them – to validate and value knowledge hitherto consigned to historical obscurity, including among the most marginalized in our communities.
Polymer Derived Ceramics with Negative Thermal Expansion Fillers: Zirconium Tungstate
Authors: Fedorova Anna , Scheffler Michael
Published: March 2019

Novel‐type bulk polymer derived ceramics are manufactured with negative thermal expanding zirconium tungstate (ZrW2O8) as filler material. A pressure‐induced phase transformation of the α‐ZrW2O8 phase into the γ‐ZrW2O8 is observed, caused by high thermal mismatch stresses between the polymer derived ceramic matrix and the filler particles. The zirconium tungstate phase influences the overall thermal expansion behavior, and an additional annealing step is added to the manufacturing process to trigger the re‐transformation of the filler and to restore the negative thermal expansion behavior of the bulk polymer derived ceramic.
In Situ Regulating the Order–Disorder Phase Transition in Cs2AgBiBr6 Single Crystal toward the Application in an X‐Ray Detector
Authors: Yuan Weinan , Niu Guangda , Xian Yeming , Wu Haodi , Wang Huamin , Yin Hang , Liu Peng , Li Wenzhe , Fan Jiandong
Published: March 2019

The double perovskite Cs2AgBiBr6 single crystal holds great potential for detecting applications because of its low minimum detectable dose rate and toxic‐free merit. Nevertheless, the disordered arrangement of Ag+/Bi3+ usually gives rise to unexpected structural distortion and thereafter heavily influences the photoelectric properties of the Cs2AgBiBr6 single crystal. Herein, phenylethylamine bromide is demonstrated to be capable of in situ regulation of the order–disorder phase transition in the Cs2AgBiBr6 single crystal. The improved ordering extent of alternatively arranged [AgX6]5− and [BiX6]3− octahedra is theoretically and experimentally proven to decrease the defect density and suppress self‐trapped exciton formation, and thereby tune the band gap and enhance the carrier mobility, which consequently promotes its application in an X‐ray detector. The performance of a corresponding detector based on PEA‐Cs2AgBiBr6 single crystal displays superior performances, e.g., longer carrier drift distance, higher photoconductive gain, and faster current response (13 vs 3190 µs). Prominently, the as‐fabricated PEA‐Cs2AgBiBr6 single‐crystal X‐ray detector has an extremely high sensitivity with a value of 288.8 µC Gyair−1 cm−2 under a bias of 50 V (22.7 V mm−1), which largely outperforms those of their counterparts with lower ordering structure.
A Rechargeable Battery with an Iron Metal Anode
Authors: Wu Xianyong , Markir Aaron , Xu Yunkai , Zhang Chong , Leonard Daniel P. , Shin Woochul , Ji Xiulei
Published: March 2019

To date, tremendous efforts of the battery community are devoted to batteries that employ Li+, Na+, and K+ as charge carriers and nonaqueous electrolytes. However, aqueous batteries hold great promise for stationary energy storage due to their inherent low cost and high safety. Among metal batteries that use aqueous electrolytes, zinc metal batteries are the focus of attention. In this study, iron as an anode candidate in aqueous batteries is investigated because iron is undoubtedly the most earth‐abundant and cost‐effective metal anode. Reversible iron plating/stripping in a FeSO4 electrolyte is demonstrated on the anode side and reversible topotactic (de)insertion of Fe2+ in a Prussian blue analogue cathode is showcased. Furthermore, it is revealed that LiFePO4 can pair up with the iron metal anode in a hybrid cell, delivering stable performance as well.
Eradicating Multidrug‐Resistant Bacteria Rapidly Using a Multi Functional g‐C3N4@ Bi2S3 Nanorod Heterojunction with or without Antibiotics
Authors: Li Yuan , Liu Xiangmei , Tan Lei , Cui Zhenduo , Jing Doudou , Yang Xianjin , Liang Yanqin , Li Zhaoyang , Zhu Shengli , Zheng Yufeng , Yeung Kelvin Wai Kwok , Zheng Dong , Wang Xianbao , Wu Shuilin
Published: March 2019

Wound infections caused by multidrug‐resistant (MDR) bacteria are hard to treat because of tolerance to existing antibiotics, repeated infection, and concomitant inflammation. Herein, zinc atom–doped g‐C3N4 and Bi2S3 nanorod heterojunctions (CN–Zn/BiS) are investigated for disinfection under near‐infrared light (NIR). The photocatalysis of CN–Zn/BiS is enhanced because of efficient charge separation during the interface electron field and increased oxygen adsorption capacity. Then, 99.2% antibacterial efficiency is shown toward methicillin‐resistant Staphylococcus aureus (MRSA) and 99.6% toward Escherichia coli under 10 min NIR irradiation. Meanwhile, a strategy for the combination of lapsed β‐lactam antibiotics with the photosensitizer CN–Zn/BiS is provided to kill MRSA by NIR without observable resistance, suggesting an approach to solve the problem of bacterial infection with NIR light penetrability and for exploiting new anti‐infection methods. The CN–Zn/BiS nanocomposite can also regulate genes and the inflammatory response through inflammatory factors (IL‐1β, IL‐6, TNF‐α, and iNOS) in vivo to accelerate tissue regeneration and thereby promote wound healing.
Hot Glue Gun Releasing Biocompatible Tissue Adhesive
Authors: Shagan Alona , Zhang Wei , Mehta Manisha , Levi Shira , Kohane Daniel S. , Mizrahi Boaz
Published: March 2019

Tissue bioadhesives are widely used in dermatology, surgery rooms, and in the field. Despite their advantages over sutures and staples, currently available tissue glues are limited by their mechanical properties and toxicity. Here, a new approach is described for wound closure that is based on a biocompatible, low melting point four‐armed N‐hydroxy succinimide‐modified polycaprolactone (star‐PCL‐NHS). Star‐PCL‐NHS is inserted into a hot melt glue gun, melts upon minimal pressure, and is extruded directly onto the wound, where it solidifies, bonding strongly with both edges of the wound. Changes in molecular weight allow control of adhesive strength, melting point, and elasticity properties. In vitro and in vivo evaluations confirm the biocompatibility of this system. The straightforward synthetic scheme and the simple delivery method, combined with the desirable mechanical properties, tunability, and tissue compatibility, are desirable traits in wound management.
UV‐Curable Silver Electrode for Screen‐Printed Thermoelectric Generator
Authors: Choi Hyeongdo , Kim Yong Jun , Song Jinseob , Kim Choong Sun , Lee Gyu Soup , Kim Seongho , Park Jiwon , Yim Se Hwan , Park Sang Hyun , Hwang Hye Rim , Hong Min‐Hee , Veluswamy Pandiyarasan , Cho Byung Jin
Published: March 2019

Fabricating thermoelectric generators (TEGs) using the screen‐printing process has advantages, including mass production, device scalability, and system applicability. However, the thick film formed through the process typically has low film density, and reduced performance, because of the presence of pores in the film created by the vaporization of the resin during high‐temperature annealing. During the soldering process used for thermoelectric module fabrication, the printed solder infiltrates into the screen‐printed electrodes through the micropores in the electrodes, causing cracks of the electrode film and an increase in resistivity. In this paper, an ultraviolet radiation (UV)‐curable process for screen‐printed electrodes is reported. The paste for the electrodes is synthesized by mixing Ag flakes that can be cured at low temperature with a UV resin. Scanning electron microscope images show that the UV‐curing process significantly reduces pores and thereby results in a smooth‐surfaced electrode layer. The film density after crystallization is also enhanced. TEGs composed of 72 couples with UV‐curable Ag electrodes generate a high power density of ≈6.69 mW cm−2 at a temperature difference of 25 °C; the device resistance is ≈0.75 Ω, and the figure of merit of the device is recorded to be 0.57, which is the highest among the printed TEGs.
Printing Hydrogels and Elastomers in Arbitrary Sequence with Strong Adhesion
Authors: Yang Hang , Li Chenghai , Yang Meng , Pan Yudong , Yin Qianfeng , Tang Jingda , Qi Hang Jerry , Suo Zhigang
Published: March 2019

Many recently demonstrated devices require the integration of hydrogels and hydrophobic elastomers. Extrusion print is a promising method for rapid prototyping but existing approaches do not fulfill a basic requirement: print integrated structures of a hydrogel and an elastomer, in arbitrary sequence, with strong adhesion. This paper demonstrates an approach to fulfill this requirement. During print, the ink of each material flows through a nozzle under a pressure gradient but retains the shape against gravity and capillarity. During cure, covalent bonds form to link monomer units into polymer chains, crosslink the polymer chains into the polymer networks of the hydrogel and the elastomer, as well as interlink the two polymer networks into an integrated structure. The approach covalently interlinks the hydrogel network and the elastomer network by adding an interlink initiator in one of the inks. An adhesion energy above 5000 J m−2 is demonstrated. Printed morphing structures survive swelling and printed artificial axons survive repeated hits of a hammer. This approach opens a road to the development of soft devices for broad applications in medicine and engineering.
Multilayer Polypyrrole Nanosheets with Self‐Organized Surface Structures for Flexible and Efficient Solar–Thermal Energy Conversion
Authors: Wang Xu , Liu Qingchang , Wu Siyao , Xu Baoxing , Xu Hangxun
Published: March 2019

Converting solar energy into concentrated heat is very appealing for various applications. Polypyrrole (PPy) is known to possess excellent photothermal property with low thermal conductivity, and thus is an ideal candidate for solar–thermal energy conversion. However, solar–thermal materials based on PPy or other conducting polymers still exhibit limited energy conversion efficiency due to the lack of effective light‐trapping schemes. Here, it is demonstrated that multilayer PPy nanosheets with spontaneously formed surface structures such as wrinkles and ridges via sequential polymerization on paper substrates can dramatically enhance broadband and wide‐angle light absorption across the full solar spectrum, leading to an impressive solar–thermal conversion efficiency of 95.33%. The intriguing solar–thermal properties and structural features of multilayer PPy nanosheets can be used for solar heating and photoactuators. Meanwhile, when used for solar steam generation, the measured efficiency could achieve ≈92% under one sun irradiation. The hierarchically multilayer structure is mechanically flexible and robust, holding great potential for practical solar energy utilization. This study provides a simple and straightforward approach toward engineering light‐weight and thermally insulating polymers into efficient solar–thermal materials for emerging solar energy‐related applications.
Controlling Monomer Feeding Rate to Achieve Highly Crystalline Covalent Triazine Frameworks
Authors: Liu Manying , Jiang Kai , Ding Xing , Wang Shaolei , Zhang Chengxin , Liu Jing , Zhan Zhen , Cheng Guang , Li Buyi , Chen Hao , Jin Shangbin , Tan Bien
Published: March 2019

The synthesis of highly crystalline covalent triazine frameworks (CTFs) with ultrastrong covalent bonds (aromatic CN) from the triazine linkage presents a great challenge to synthetic chemists. Herein, the synthesis of highly crystalline CTFs via directly controlling the monomer feeding rate is reported. By tuning the feeding rate of monomers, the crystallization process can be readily governed in a controlled manner in an open system. The sample of CTF‐HUST‐HC1 with abundant exposed {001} crystal facets has the better crystallinity and thus is selected to study the effect of high crystallinity on photoelectric properties. Owing to the better separation of photogenerated electron–hole pairs and charge transfer, the obtained highly ordered CTF‐HUST‐HC1 has superior performance in the photocatalytic removal of nitric oxide (NO) than its lesser crystalline counterparts and g‐C3N4.
Magnetite/Ceria Nanoparticle Assemblies for Extracorporeal Cleansing of Amyloid‐β in Alzheimer's Disease
Authors: Kim Dokyoon , Kwon Hyek Jin , Hyeon Taeghwan
Published: March 2019

Accumulation of amyloid‐β (Aβ) peptides in the brain is regarded as a major contributor to the pathogenesis and progression of Alzheimer's disease (AD). However, development of clinically relevant techniques to reduce Aβ levels in AD patients is hindered by low efficiency and/or side effects. Here, an extracorporeal Aβ cleansing system, where multifunctional magnetite/ceria nanoparticle assemblies are used to remove Aβ peptides from flowing blood by specific capture and magnetic separation, is reported. The magnetite nanoparticles in the nanoassembly core enable the magnetic isolation of the captured Aβ peptides by generating a large attraction force under an external magnetic field. The ceria nanoparticles in the nanoassembly shell relieve oxidative stress by scavenging reactive oxygen species that are produced by immune response during the process. Blood Aβ cleansing treatment of 5XFAD transgenic mice not only demonstrates the decreased Aβ levels both in the blood and in the brain but also prevents the spatial working memory deficits, suggesting the potential of the method for AD prevention and therapy.
Electric Bus: A Critical Overview on the Dawn of Its Widespread Uptake
Authors: Pagliaro Mario , Meneguzzo Francesco
Published: March 2019

The battery powered electric bus is the first electric vehicle whose market share in the world's leading industrial economy has surpassed the 80%. Within the next decade (2019–2026), the authors argue, electric buses powered by Li‐ion batteries and hydrogen fuel cells will become ubiquitous across the world, displacing bus and coaches powered by fossil fuels burned in the internal combustion engine. Critically reviewing the economic, health, and environmental benefits of the electric bus, this essay offers an updated outlook in a key area of the global energy transition.
Analyzing the Electronic Coupling in Molecular Crystals—The Instructive Case of α‐Quinacridone
Authors: Winkler Christian , Mayer Florian , Zojer Egbert
Published: March 2019

In the present article, an evaluation of different approaches for estimating the electronic coupling and charge‐transport parameters in organic semiconductors is provided. As a testbed for that comparison, the α‐polymorph of quinacridone is chosen. This system is particularly well suited for the purpose, as α‐quinacridone intermolecular interactions in distinct crystallographic directions are dominated by the three mechanisms most relevant in organic semiconductors: π‐stacking, H‐bonding, and van der Waals stacking. Density‐functional theory‐based simulations yield a comparably complex band structure, which provides the means for demonstrating shortcomings of commonly applied approaches. These include the estimation of transport properties based on bandwidths and the calculation of electronic transfer integrals considering molecular dimers. As a particularly promising alternative, the fitting of suitably complex tight‐binding models to the DFT‐calculated bands in the entire Brillouin zone is proposed. These fits bear the advantage of directly producing intermolecular coupling constants for all relevant neighboring molecules as input parameters for hopping and dynamic disorder models. They also yield an analytic expression for the electronic bands. These allow the extraction of parameters relevant for band‐transport models (like group velocities and effective masses) in the entire Brillouin zone.
Tunable Wood by Reversible Interlocking and Bioinspired Mechanical Gradients
Authors: Frey Marion , Biffi Giulia , Adobes‐Vidal Maria , Zirkelbach Meri , Wang Yaru , Tu Kunkun , Hirt Ann M. , Masania Kunal , Burgert Ingo , Keplinger Tobias
Published: March 2019

Elegant design principles in biological materials such as stiffness gradients or sophisticated interfaces provide ingenious solutions for an efficient improvement of their mechanical properties. When materials such as wood are directly used in high‐performance applications, it is not possible to entirely profit from these optimizations because stiffness alterations and fiber alignment of the natural material are not designed for the desired application. In this work, wood is turned into a versatile engineering material by incorporating mechanical gradients and by locally adapting the fiber alignment, using a shaping mechanism enabled by reversible interlocks between wood cells. Delignification of the renewable resource wood, a subsequent topographic stacking of the cellulosic scaffolds, and a final densification allow fabrication of desired 3D shapes with tunable fiber architecture. Additionally, prior functionalization of the cellulose scaffolds allows for obtaining tunable functionality combined with mechanical gradients. Locally controllable elastic moduli between 5 and 35 GPa are obtained, inspired by the ability of trees to tailor their macro‐ and micro‐structure. The versatility of this approach has significant relevance in the emerging field of high‐performance materials from renewable resources.
Electrochromic Properties of Nanostructured WO3 Thin Films Deposited by Glancing‐Angle Magnetron Sputtering
Authors: Wang Meihan , Chen Yun , Gao Bowen , Lei Hao
Published: March 2019

Tungsten oxide thin films are prepared by glancing‐angle reactive magnetron sputtering at room temperature. The surface and cross‐section morphologies are characterized by FE‐SEM and TEM. The electrochromic properties of the thin films are studied using a three‐electrode system in 1 m LiClO4/PC solution. When the glancing angle is kept at 80°, a nanocolumnar structured film is obtained. This nanocolumnar structured film shows a lower driving potential and better stability compared to the dense film. The charge capacity per unit area of the nanocolumnar structured film is determined to be 30.85 mc cm−2. The diffusion rates of injection and detachment of ions are determined to be Din = 6.57 × 10−10 cm2 s−1 and Dde = 6.55 × 10−10 cm2 s−1 under an applied potential of ±1.2 V, respectively. The optical modulation amplitude of the nanocolumnar structured film reaches 65% at a wavelength of 600 nm and the optical density is superior to that of the dense film.
Designed Memristor Circuit for Self‐Limited Analog Switching and its Application to a Memristive Neural Network
Authors: Song Hanchan , Kim Young Seok , Park Juseong , Kim Kyung Min
Published: March 2019

Analog memristors enable compact neuromorphic computing with low power consumption. One of the issues with the technology is slow precise analog data programming. In this study, a novel analog data programming method utilizing a self‐limited set switching is proposed. The method can transfer any resistance values from reference resistors to the target memristor accurately inside a crossbar array by performing an appropriate voltage clocking. An ideal memristor model based on the method is proposed and a Ti‐doped NbOx charge trap memristor is evaluated as a promising candidate for applications. The characteristic error of the Ti‐doped NbOx memristor device is about 5% on average, compared to the ideal memristor, and configuring optimum parallel resistors in the circuit further improves this to 2.95%. The method is then applied to program a memristive neural network and this error is confirmed negligible; thus the proposed method is viable.
Dynamic PCBM:Dimer Population in Solar Cells under Light and Temperature Fluctuations
Authors: Pont Sebastian , Durrant James R. , Cabral João T.
Published: March 2019

Photoinduced dimerization of phenyl‐C61‐butyric acid methyl ester (PCBM) has a significant impact on the stability of polymer:PCBM organic solar cells (OSCs). This reaction is reversible, as dimers can be thermally decomposed at sufficiently elevated temperatures and both photodimerization and decomposition are temperature dependent. In operando conditions of OSCs evidently involve exposure to both light and heat, following periodic diurnal and seasonal profiles. In this work, the kinetics of dimer formation and decomposition are examined and quantified as a function of temperature, light intensity, blend composition, and time. The activation energy for photodimerization is estimated to be 0.021(3) eV, considerably smaller than that for decomposition (0.96 eV). The findings are benchmarked with a variety of conjugated polymer matrices to propose a descriptive dynamic model of PCBM:dimer population in OSCs, and a framework is proposed to rationalize its interplay with morphology evolution and charge quenching. The model and parameters enable the prediction of the dynamic and long‐term PCBM:dimer populations, under variable temperature and light conditions, which impact the morphological stability of OSCs.