bluuebunny/crossref_metadata_2025 huggingface dataset:
Exportkontrolle zwischen europäischen und nationalen Interessen
Authors: Bazan Jonas
Published: September 2020

The European export control system of dual-use goods is a pillar in the fight against proliferation of weapons of mass destruction and for the protection of human rights. But who actually decides in the complex entanglement of national security interests, European trade policy and international prevention regimes which goods are allowed for export out of the European Union?

In his study, which was awarded the “Aquila ascendens” knowledge prize of the DialogForum Sicherheitspolitik, Jonas Bazan analyses institutional power shifts in the European export control system and reveals whether a structural Europeanisation has taken place or whether the European institutions remain subordinate to national interests of the member states.
The prevalence of low anterior resection syndrome in rectal cancer patients who underwent surgical treatment in Isfahan City Hospital during 2012-2018
Authors: Sanei Behnam , Ghasemi Fard , Kolahduzan Mohsen
Published: September 2020

Objective. We aimed to determine the relative frequency of low anterior resection syndrome (LARS) in patients with rectal cancers who underwent surgical treatment in Isfahan. Methods. We evaluated all patients who were referred to the surgery clinic of Saint Al-Zahra hospital in Isfahan within six years. If LARS was identified, according to the LARS score tool, the frequency of resection complications, factors affecting the LARS, morbidity, and mortality, the frequency distribution of defecation, stool consistency, and rate of significant improvement was evaluated. Results. Fifty-two patients were evaluated. The prevalence of LARS was 78.8%. Postoperative fecal and gas incontinence, clustering, fecal frequency, and fecal urgency in LARS patients were significantly higher than in patients without LARS (P<0.05). There was no significant difference between the two groups in terms of factors affecting the LARS (p<0.05). In most of the patients with LARS, the defecation frequency was more than seven times a week (82.1%), and they mostly had liquid stool (61.5%). 95.5% of the patients with LARS showed significant improvement, which was mostly after 7-11 months (38.5). There was a significant difference between the frequency distribution of defecation, stool consistency, and significant improvement status in patients with and without LARS. Conclusion. LARS occurs commonly among patients undergoing LAR with TME and it is associated with more resection complications. Patients with LARS have significantly higher frequency of defecation per week and liquid stools and mostly achieve significant improvements. Other factors might not be significantly different between patients with or without LARS.
Mythenauslegung, römische Königszeit und der Tod des Kaiser Valens: Christliche Interpretationen von Orosius bis Isidor von Sevilla
Authors: Rohmann Dirk
Published: September 2020

Chronicles became the dominant historical genre in the transition period between Late Antiquity and the Early Middle Ages. While individual authors tended to build one on another, they also exerted considerable licence in rearranging the tralaticious material they found in previous compilations. Comparing Latin with Greek authors– Orosius, Isidore of Seville, Gregory of Tours, and John Malalas – the present contribution argues that all of these historical works, while summarising the history of antiquity, reflect discourses of their own day and age. These differences can be appreciated in comparing their specific views on the origin of sin in the world, on king Numa, and on the death of the Arian emperor Valens.
Problems and prospects of MERCOSUR as a civilizational political project of South America
Authors: Gorbachev Mikhail Valer'evich
Published: September 2020

  This article discusses the political projects of civilizational level, which are designed and implemented in South America. The author examines MERCOSUR as the largest regional civilizational political project, its sociocultural foundation and institutional superstructure; functionality of the “core state” in formation and maintenance of the South American civilizational political project; problems of development and future implementation. The article reveals conflict potential of MERCOSUR, as well as sociocultural capabilities for its overcoming by the “core state” of the project. The research was conducted via application of civilizational-project methodology of interpretation of policy, which is based on methodological synthesis of the principles of project approach with provisions of the theory of civilizations. The author was able to determine the value grounds of MERCOSUR, which comprise its sociocultural foundation; identify the countries competing for status of the “core state” within the framework of this project. The nature of commonality between the key participants of the projects is identified. Problems and prospect of further development of MERCOSUR civilizational projects are defined.  
The activity of German law enforcement authorities in resolving the problem of political stability: counterterrorism aspects (2013-2018)
Authors: Kornilova Ksenia Aleksandrovna
Published: September 2020

This article examines the counterterrorism policy of Germany during the third term of Angela Merkel, when the spread of terrorist threat in the territory of Germany has increased. The subject of this research is the activity of law enforcement authorities in development and implementation of German counterterrorism policy strategy, which include preemptive and prevention measures, forcible methods, and share of intelligence between the departments. The goal of this work consists in analysis and assessment of the achievements and failures of counterterrorism policy of Germany. Neorealism served as the key approach used in the course of this research. The conclusion is made that successfully consolidated activity of Merkel’s government and law enforcement authorities led to decrease in the number of terrorist attacks and strengthening of political stability in Germany. For indicating achievements and problematic aspects of German counterterrorism activity during the indicated period, the author translated from German the reports of law enforcement authorities on the instances of violence and prevented terrorist attacks, as well as mass media materials testifying to successful prevention of terrorist attacks. The acquired materials can be valuable in teaching corresponding disciplines and within the framework of scientific research.
Matrimony in Venice during Late Renaissance Era in light of judicial institutions
Authors: Makarova Nina
Published: September 2020

The subject of this research is the several government institutions of Venice during the Late Renaissance Era that dealt with questions of matrimonial relations. Marriage played not only a crucial social role, but was also considered a church, which contributed to salvation of the faithful. Therefore, the questions of the validity of marriage or claims for separation of the spouses were considered by the Church court alone. The government institutions dealt with for offences against marriage, observed the execution of laws regarding the property of spouses, resolved custody issues of the minors, and prevented inappropriate behavior between the spouses. Special attention is given to the judicial institutions of Venice in from the perspective of their activity on matrimony. The article employs descriptive method, complemented by comparative historical analysis of the political and religious institutions of that time. The author's special contribution consists in the analysis of cases, such as the abduction of women or a breach of promise, which were interpreted differently by the religious and secular courts. As a result, in the late XVI – early XVII century, the secular administration gained prevalence in these questions.
How to act culture-congruently in the conditions of deep crisis of modern culture?
Authors: Rozin Vadim Markovich
Published: September 2020

This article discusses the problem of culture-congruent social action in the conditions of cultural crisis. Attention is turned to the fact that the principles of conformity to natural laws and cultural congruency were originally formulated in the pedagogy (Pestalozzi, Froebel, Diesterweg); however, since the comprehension of culture has changes significantly, these principles require reconsideration.  In this context, it is suggested to differentiate the modern culture, national cultures, and post-culture. Analysis is conducted on the crisis phenomena of modernity and national cultures. The article lists the current development trends that comprise post-culture, the processes and structure of which are being formed, but yet not clear. Therefore, the future is characterized with complexity and uncertainty. Based on the proposed differentiation and concepts, the author examines two ways of culture-congruent actions. One suggests the revision of usual coherent (i.e. common to the entire culture) ideas, while the other – setting the whole and essence of the phenomena of modernity and post-culture. In the author’s opinion, the need to re-establish in the usual concepts and setting the whole is not the study of culture, but a methodological criticism and structuring of patterns and hypothetical scenarios. For better understanding of this approach, the two extended examples are presented: S. Benhabib's discussion of migration policy and the author's project of a new cultural meaning of post-culture.
Lumican promotes joint fibrosis through TGF‐β signaling
Authors: Xiao Dahai , Liang Tangzhao , Zhuang Ze , He Ronghan , Ren Jianhua , Jiang Shihai , Zhu Lei , Wang Kun , Shi Dehai
Published: September 2020

Joint contracture (also known as arthrofibrosis) is a fibrotic joint disorder characterized by excessive collagen production to form fibrotic scar tissue and adhesions within joint capsules. This can severely affect day‐to‐day activities and quality of life because of a restricted range of motion in affected joints. The precise pathogenic mechanism underlying joint contractures is not fully understood. Lumican belongs to the class II small leucine‐rich repeat proteoglycan superfamily, which makes up collagen fibrils in the extracellular matrix. Lumican is ubiquitously expressed in the skin, liver, heart, uterus and articular cartilage and has reported roles in cell migration, proliferation, angiogenesis and Toll‐like receptor 4 signaling. Previous research has suggested that lumican is involved in the pathogenesis of several fibrotic diseases. Because joint contracture resembles a fibrotic disease, we aimed to investigate the role of lumican in the development of joint contracture in vitro. Here, we showed that protein levels were up‐regulated in the fibrotic joint capsule versus control. We observed that lumican significantly enhanced the proliferation, migration and fibroblast–myofibroblast transition of synovial fibroblasts. Moreover, lumican led to increased transcription of alpha‐smooth muscle actin, matrix metallopeptidase 9, Collagen I, plasminogen activator inhibitor 1 and transforming growth factor‐β in vitro. Lumican treatment promoted collagen lattice contraction in a dose‐dependent manner as early as 24 h after treatment. Thus, our studies reveal that lumican could promote fibroblast–myofibroblast transition and joint contracture.
An investigation into the molecular basis of cancer comorbidities in coronavirus infection
Authors: Facchiano Antonio , Facchiano Francesco , Facchiano Angelo
Published: September 2020

Comorbidities in COVID‐19 patients often worsen clinical conditions and may represent death predictors. Here, the expression of five genes, known to encode coronavirus receptors/interactors (ACE2, TMPRSS2, CLEC4M, DPP4 and TMPRSS11D), was investigated in normal and cancer tissues, and their molecular relationships with clinical comorbidities were investigated. Using expression data from GENT2 databases, we evaluated gene expression in all anatomical districts from 32 normal tissues in 3902 individuals. Functional relationships with body districts were analyzed by chilibot. We performed DisGeNet, genemania and DAVID analyses to identify human diseases associated with these genes. Transcriptomic expression levels were then analyzed in 31 cancer types and healthy controls from approximately 43 000 individuals, using GEPIA2 and GENT2 databases. By performing receiver operating characteristic analysis, the area under the curve (AUC) was used to discriminate healthy from cancer patients. Coronavirus receptors were found to be expressed in several body districts. Moreover, the five genes were found to associate with acute respiratory syndrome, diabetes, cardiovascular diseases and cancer (i.e. the most frequent COVID‐19 comorbidities). Their expression levels were found to be significantly altered in cancer types, including colon, kidney, liver, testis, thyroid and skin cancers (P < 0.0001); AUC > 0.80 suggests that TMPRSS2, CLEC4M and DPP4 are relevant markers of kidney, liver, and thyroid cancer, respectively. The five coronavirus receptors are related to all main COVID‐19 comorbidities and three show significantly different expression in cancer versus control tissues. Further investigation into their role may help in monitoring other comorbidities, as well as for follow‐up of patients who have recovered from SARS‐CoV‐2 infection.
Soil mass balance
Authors: Yoo Kyungsoo
Published: September 2020

Soils form at the intersection of the lithosphere, biosphere, atmosphere, and hydrosphere and thus are the location where the fluxes of minerals, water and solutes, and organic matter occur. The directions and sizes of these fluxes, and their sensitivities to environmental forcings, determine the soil's mass and composition, as well as its temporal and spatial characteristics. The quantitative relationships between the material fluxes and the resulting composition of soils are the subject of soil mass balance analysis. Soil mass balance analysis also informs our understanding of time as a soil‐forming factor because it facilitates the quantification of soil turnover times. Constructing a mass balance model for a soil requires delineating the soil's boundary, which generates philosophical questions related to soil definitions per se. It is thus not surprising that geochemical, geomorphic, and carbon mass balances have played key roles in advancing our knowledge of the biogeochemical evolution of soils and soils' role in landscape evolution and the carbon cycle.
Endorheic water
Authors: Wang Jida
Published: September 2020

Endorheic water is the collection of water mass that is landlocked without surface outlets and thus equilibrates chiefly through evapotranspiration. The watersheds that retain endorheic water are termed endorheic basins, which constitute approximately one‐fifth of the continental area and are mostly arid or semiarid. As a result, endorheic water is limited in both flow and storage. Fresh water is particularly scarce in endorheic basins as most of their surface water is stored in terminal lakes that are usually saline. Due to its landlocked hydrology and arid climates, the already limited endorheic water is vulnerable to subtle flux perturbations, which have been amplified by climate change and human water management. Examples include the shrinkage of many saline lakes over the past century and the recent decadal loss of total water storage from global endorheic basins. An improved understanding of endorheic water dynamics is critically important to not only water security on the Earth's drylands but also the closure of the terrestrial water budget.
Regional and urban planning for growth in China
Authors: Wang Zheng , Wu Fulong
Published: September 2020

Chinese planning in the post‐reform era is primarily concerned with stimulating economic growth through urban developments. For cities, land sales revenue is an important source of income and a key driver of gross domestic product (GDP) growth, which is a core criterion for government career promotions. City planning involves creating an investment‐friendly built environment through nonstatutory spatial plans that can be used for place promotion. Furthermore, economic growth helps to consolidate the state's political power. Through the state's monopoly of land, local states are able to use land as collateral to deliver large urban projects and reap the greatest financial benefits. The urban governance of strategically important projects is also designed with a view to stimulating growth. Planning powers are assigned to development‐oriented state organizations while social responsibilities such as relocating residents are delegated to district and subdistrict governments. National‐ and regional‐level planning has been strengthened in the past decade to address rampant urban expansions and intense intercity competition which have had severe environmental and socioeconomic consequences. Yet, regional planning is not about curbing growth but about better coordinating it. However, due to insufficient and sometimes overlapping governance responsibilities being distributed to three national ministries, the regulatory power of national and regional planning is limited.
More‐than‐human geographies
Authors: Isaacs Jenny R.
Published: September 2020

More‐than‐human geographies (MTHG) trace the multiplicity of encounters and entangled relations between humans and nonhuman others. They explore different ways of sensing and conveying how the human is always “more than human,” that is, “enmeshed” with other beings, elements, forces, and objects within dynamic assemblages. Combining insights and approaches from the natural and physical sciences, the environmental humanities, (feminist) science and technology studies, actor‐network theory, new materialism, performance studies, and nonrepresentational theory, MTHG map onto how human geography and cognate fields such as anthropology and sociology might revisit the category of the human by better attending to the capacity of matter – both living and nonliving – to affect and be affected.
Diffusion
Authors: Pumain Denise
Published: September 2020

The concept of diffusion describes regularities in the temporal propagation of people, objects, practices, or information in geographical space. The Swedish geographer Torsten Hägerstrand attached his name as early as the 1950s to the first formulation of the theory of the spatial diffusion of innovations. The spatial constraint on movement is expressed both in terms of proximity and in terms of connectivity. The theory establishes a generic link between behaviors observed at the microscale (those of individuals) and the resulting configurations at the meso‐ or macroscale (regional, continental, and global). Indeed, spatial diffusion theory, with associated concepts and simulation models, has found applications for analyzing and predicting a large variety of spatiotemporal processes. The main ones concern migrations, innovation diffusion, and the spread of epidemics. Recent research focuses on the transmission of epidemics, information, and opinions, particularly via digital networks.
Gateways
Authors: O'Kelly Morton E.
Published: September 2020

A gateway is a special node that provides an entry point to, or an exit from, a region. Here, a region is a large area, possibly a country, or several countries. In modern times, gateways continue to serve as important transport nodes.
Adaptive controller design with prescribed performance for switched nonstrict feedback nonlinear systems with actuator failures
Authors: Ovaysi Elham , Kamali Marzieh , Javad Yazdanpanah Mohammad
Published: September 2020

This article is concerned with the adaptive output‐feedback control of switched nonstrict feedback nonlinear systems. By introducing a novel error surface, an adaptive control strategy is proposed for the general case where the nonlinear functions and the control gain functions are unknown, and the states are unmeasurable. The considered switched nonlinear system contains unknown actuator failures, which are modeled as both loss of effectiveness and lock‐in‐place. In order to improve the transient performance in the presence of unknown actuator failures, the prescribed performance approach is used. The “explosion of complexity” problem is avoided through using low‐pass filters. The stability of the closed‐loop system under arbitrary switching is shown using Lyapunov stability theory, based on which, the tracking error is shown to converge to a small residual set with the prescribed performance bounds. The advantages of the proposed technique are verified through simulations of two numerical and practical examples.
Integration of barometric and GPS altimeters via adaptive data fusion algorithm
Authors: Hajiyev Chingiz , Hacizade Ulviye , Cilden‐Guler Demet
Published: September 2020

An adaptive integrated navigation system, consisting of barometric altimeter (Baro) and GPS, is presented. The integration is achieved by using an adaptive data fusion algorithm with the filter gain correction. Proposed adaptive data fusion algorithm utilizes the measurement noise scale factor in order to reduce the effects of the incorrect barometric altimeter measurements on the estimation procedure. By using the algorithm, incorrect baro measurements are corrected by the system without any impact on the good estimation behavior. Performance of the proposed Baro/GPS integrated system is examined by simulations for altitude estimation of an aircraft.
Leveraging the Modularity of Biomaterial Carriers to Tune Immune Responses
Authors: Tsai Shannon J. , Black Sheneil K. , Jewell Christopher M.
Published: September 2020

Biomaterial carriers offer modular features to control the delivery and presentation of vaccines and immunotherapies. This tunability is a distinct capability of biomaterials. Understanding how tunable material features impact immune responses is important to improve vaccine and immunotherapy design, as well as clinical translation. Here the modularity of biomaterial properties is discussed as a means of controlling encounters with immune signals across scales—tissue, cell, molecular, and time—and ultimately, to direct stimulation or regulation of immune function. These advances are highlighted using illustrations from recent literature across infectious disease, cancer, and autoimmunity. As the immune engineering field matures, informed design criteria could support more rational biomaterial carriers for vaccination and immunotherapy.
Single‐Atom In‐Doped Subnanometer Pt Nanowires for Simultaneous Hydrogen Generation and Biomass Upgrading
Authors: Zhu Yiming , Zhu Xiaorong , Bu Lingzheng , Shao Qi , Li Yafei , Hu Zhiwei , Chen Chien‐Te , Pao Chih‐Wen , Yang Shize , Huang Xiaoqing
Published: September 2020

Replacing the anodic oxygen evolution reaction (OER) with a thermodynamically favorable ethanol oxidation reaction (EOR) is regarded as a promising approach to simultaneously realize energy‐saving H2 evolution and high‐value chemical production. Herein, the single‐atom In‐doped subnanometer Pt nanowires (SA In‐Pt NWs) as high‐performance electrocatalysts for both the hydrogen evolution reaction (HER) and EOR under universal pH conditions is designed. The SA In‐Pt NWs/C can be employed to integrate HER with EOR to avoid the large overpotential caused by sluggish OER, which requires a smaller voltage of 0.62 V to reach 10 mA cm–2 compared with that of water splitting (2.07 V). The reaction also exhibits a high faradaic efficiency of over 93% in upgrading ethanol to valuable acetate in the anodic cell. Mechanistic investigations indicate that the combination of the ultrathin 1D morphology and single‐atom In decoration provides the maximum number of active sites and effectively activates Pt atoms for catalysis. Density functional theory calculations further demonstrate that doped In can effectively promote the HER, while also promoting the conversion of ethanol to acetate. Moreover, through the use of SA In‐Pt NWs/C as electrocatalysts, many other alcohols can also be employed as anodic feedstock to achieve coupled electrolysis.
Mapping the Multi‐Directional Mechanical Properties of Bone in the Proximal Tibia
Authors: Munford Maxwell J. , Ng K. C. Geoffrey , Jeffers Jonathan R. T.
Published: September 2020

The remodeling behavior of bone is influenced by its mechanical environment. By mapping bone's mechanical properties in detail, orthopedic implants with respect to its mechanical properties could stimulate and harness remodeling to improve patient outcomes. In this study, multiaxial apparent modulus and strength of cadaveric proximal tibial bone are mapped and predicted from computed tomography (CT) derived apparent density. Group differences are identified from testing order, subchondral depth, condyle, and sub‐meniscal bone with covariates; age and gender. Axial modulus is 50% greater than the transverse modulus. Medial axial modulus is 30% greater than the lateral side. On the lateral side, axial modulus decreases by 50% from proximal to 25 mm distal. On the medial side, axial modulus remains relatively constant. Differences are quantified for density and multiaxial modulus across all subchondral depths, and different power law relationships are provided for each location. Density explains 75% of variation when grouped by subchondral depth and condyle. Yield strength is well‐predicted across all test directions, with density predicting 81% of axial strength variation and no differences over subchondral depth. Quantified mapping of bone multiaxial modulus based on condyle and subchondral depth is shown for the first time in a clinically viable protocol using conventional CT.
Exploring Ferroelectric Switching in α‐In2Se3 for Neuromorphic Computing
Authors: Wang Lin , Wang Xiaojie , Zhang Yishu , Li Runlai , Ma Teng , Leng Kai , Chen Zhi , Abdelwahab Ibrahim , Loh Kian Ping
Published: September 2020

Recently, 2D ferroelectrics have attracted extensive interest as a competitive platform for implementing future generation functional electronics, including digital memory and brain‐inspired computing circuits. Fulfilling their potential requires achieving the interplay between ferroelectricity and electronic characteristics on the device operation level, which is currently lacking since most studies are focused on the verification of ferroelectricity from different 2D materials. Here, by leveraging the ferroelectricity and semiconducting properties of α‐In2Se3, ferroelectric semiconductor field‐effect transistors (FeSFETs) are fabricated and their potential as artificial synapses is demonstrated. Multiple conductance states can be induced in α‐In2Se3‐based FeSFETs by controlling the out‐of‐plane polarization, which enables the device to faithfully mimic biosynaptic behaviors. In comparison with charge‐trapping‐based three‐terminal synaptic devices, the electronic synapses based on α‐In2Se3 have the advantages of good controllability, fast learning, and easy integration of gate dielectric, rendering them promising for neuromorphic computing. In addition, an abnormal resistive switching phenomenon in α‐In2Se3 is reported when operated in the in‐plane ferroelectric switching mode. The findings pave the way forward for α‐In2Se3‐based FeSFETs for developing neuromorphic devices in brain‐inspired intelligent systems.
High‐Dynamic‐Range Pressure Mapping Interactions by Dual Piezo‐Phototronic Transistor with Piezo‐Nanowire Channels and Piezo‐OLED Gates
Authors: Jiang Chengming , Li Qikun , Sun Nan , Huang Jijie , Bi Sheng , Ji Ruonan , Guo Qinglei , Song Jinhui
Published: September 2020

Advanced‐performance haptic systems, with high dynamic range (DR) and high pressure sensitivity, that accurately sense the small force variations with a wide detection range are essential for robotic systems, human‐machine interactions, and medical monitoring devices. However, existing skin‐like devices, such as capacitive or electrical transistor detectors, are limited by pressure contrast or recognition accuracy, thereby blocking the development of practical engineering. In the present study, an innovative pressure mapping interaction (PMI) based on dual piezo‐phototronic transistors (DPTs) is manufactured with the capability of detecting a large pressure gradient within a wide output range for providing more tactile details. The fabricated DPT, which integrates a piezo‐nanowire channel and a piezo‐OLED gate as one module with dual enhancements of the piezo‐phototronic effect, exhibits a high DR of ≈120 dB with ≈61.2 µS kPa−1 of pressure sensitivity in the effective working region. Furthermore, by employing the diminutive DPT as the PMI pixel, the device can obtain a high position resolution of 5 µm in the optimized array structure. The methods for designing and applying the PMI demonstrate effective processes for combining the piezo‐OLED gates and the piezo‐nanowire channels, which are responsible for improving the characteristics of the pressure‐relative electrical skin and others.
Ambipolar Passivated Back Surface Field Layer for Silicon Photovoltaics
Authors: Kang Sung Bum , Park Won Jin , Jeong Myeong Hoon , Kang So‐Huei , Yang Changduk , Choi Kyoung Jin
Published: September 2020

The suppression of surface recombination is of primary importance for realizing efficient silicon photovoltaics, which is usually achieved by introducing passivation or back‐surface field (BSF) layers. In this study, it is demonstrated for the first time that self‐assembled, ferroelectric, and organic thin‐films can be used as passivating BSF layers for both n‐ and p‐type Si solar cells by switching polarization. The n‐Si/PEDOT:PSS heterojunction solar cell with the ambipolar passivated BSF exhibits an efficiency of 18.37%, which is a record‐high efficiency for organic semiconductor/n‐Si heterojunction solar cells. In addition, homojunction p‐Si solar cells with the ambipolar passivated BSF yield superior performance compared to aluminium‐BSF cells. Finite‐difference time‐domain simulations reveal that the electric field due to the ferroelectric layer extends deep into the backside of Si, causing band bending and, consequently, reducing surface recombination. Moreover, the solar cell with passivated BSF maintains > 95% of its initial performance even after 1000 h of the standard damp heat test. This work endows Si‐based photovoltaics with the superior passivation and high‐performance which were previously exclusive to inorganics.
2D Fabrication of Tunable Responsive Interpenetrating Polymer Networks from a Single Photoresist
Authors: Michalek Lukas , Bialas Sabrina , Walden Sarah L. , Bloesser Fabian R. , Frisch Hendrik , Barner‐Kowollik Christopher
Published: September 2020

Light‐induced curing of photoresists is a well‐established technique to fabricate polymer networks with precise control over the material properties. Herein, control is exerted over network material properties of a single polymer blend through the spatiotemporally controlled incorporation of secondary polymer networks resulting in interpenetrating polymer networks (IPNs). Light gated control over materials properties of IPNs is assessed theoretically by applying the general rule of mixture and experimentally by using a multifunctional polymer resist. The full IPNs are formed through covalent bonds, based on photocuring of the complementary photoreactive groups o‐methyl benzaldehyde (UV light) and styrylpyrene (visible light). Applied to a spin coated polymer blend of UV light curable responsive poly(4‐vinylpyridine) (P4VP) and visible light curable poly(methyl methacrylate) (PMMA), the developed platform technology not only affords spatial control over the curing of the pH‐swellable P4VP component from the polymer blend, but also allows adjustment of the extent of swelling by forming an IPN through subsequent curing of the PMMA component. Gated only by light irradiation of a polymer blend, it is possible to control IPN formation in 2D structures, which precisely adjusts the swelling behavior of the respective materials segments.
Modulating Surface/Interface Structure of Emerging InGaN Nanowires for Efficient Photoelectrochemical Water Splitting
Authors: Lin Jing , Wang Wenliang , Li Guoqiang
Published: September 2020

Photoelectrochemical (PEC) water splitting provides a promising approach to convert solar energy into hydrogen. Developing active, stable, and cost‐effective semiconductors photoelectrodes is of great significance for achieving high‐efficiency and large‐scale hydrogen production. InGaN nanowires as an important candidate have gained a great upsurge in solar water splitting due to its tunable gap, high electron mobility, large active area, and excellent chemical stability. To obtain state‐of‐the‐art InGaN nanowires‐based photoelectrodes, tremendous efforts have been devoted to enhance light absorption capacity, charge carrier dynamics, and redox activity. In this review, recent advances in InGaN nanowires as photoelectrodes for PEC water splitting are comprehensively presented, with a focus on photoelectrode optimization strategies from the aspects of surface and interface structure modulation including doping engineering, energy band engineering, heterostructure engineering, and micro‐nano engineering. The representative applications of InGaN nanowires‐based PEC tandem cell are also discussed. Finally, perspectives on remaining challenges and future development are outlined.
Interfacial Structure and Composition Managements for High‐Performance Methylammonium‐Free Perovskite Solar Cells
Authors: Li Shunde , Liu Zhou , Qiao Zhi , Wang Xiao , Cheng Lei , Zhai Yufeng , Xu Qiaofei , Li Zhimin , Meng Ke , Chen Gang
Published: September 2020

The methylammonium (MA)‐free perovskite solar cells (PSCs) have drawn broad attention due to their excellent thermostability. However, the efficiency of these devices is inferior to most state‐of‐the‐art PSCs. Herein, the photovoltaic performance of the MA‐free PSCs is enhanced by constructing interfacial capping layers with a pair of alkylammonium halides, n‐propylammonium (PA) iodide and propane‐1,3‐diammonium (PDA) iodide. The structure and composition of the interfacial layers are comprehensively investigated and their correlation with the device performance is presented in terms of defect passivation efficacy, energy level alignment, and hydrophobicity for moisture resistance. The PSC devices based on the PAI and PDAI2 treated MA‐free perovskite films demonstrate better power conversion efficiencies (PCEs) and stabilities than the reference devices without the interfacial layers. Although the PAI‐treated devices exhibit the highest PCE of 21.1%, the PDAI2‐treated PSCs demonstrate the exceptional thermal and humidity stabilities.
Recent Advances and Optimization Strategies on the Electrolytes for Hard Carbon and P‐Based Sodium‐Ion Batteries
Authors: Shen Liying , Shi Shanshan , Roy Swagata , Yin Xiuping , Liu Wenbo , Zhao Yufeng
Published: September 2020

Hard carbons (HCs) and P‐based materials (including red phosphorus, black phosphorus, and metal phosphides) represent the most promising anodes for the commercialization of sodium ion batteries. The electrochemical performance of SIBs is determined not only by the structure of electrode materials, but it is also highly dependent on the matched electrolyte. In this review, the optimization, the matching strategies and the advanced characterization techniques of the electrolytes system for HCs and P‐based anodes are discussed based on the recent advance. The effective optimization strategies are summarized from three aspects: sodium salts, solvents, and additives. The challenges and perspectives are also discussed in this review.
A Click Chemistry Strategy for the Synthesis of Efficient Photoinitiators for Two‐Photon Polymerization
Authors: Henning Irene , Woodward Adam W. , Rance Graham A. , Paul Benjamin T. , Wildman Ricky D. , Irvine Derek J. , Moore Jonathan C.
Published: September 2020

It is reported that efficient photoinitiators, suitable for two‐photon polymerization, can be obtained using the copper catalyzed azide/alkyne cycloaddition reaction. This click chemistry strategy provides a modular approach to the assembly of photoinitiators that enables the rapid variation of key fragments to produce photoinitiators with desirable properties. To assess the performance of the first‐in‐class photoinitiators generated by this approach, a screening method is developed to enable the rapid determination of polymerization and damage thresholds in numerous photoresists during two‐photon polymerization. The degree of consumption of vinyl groups (DC) and homogeneity of the polymerization are further assessed by micro‐Raman spectroscopy. Finally, more complex structures are fabricated to demonstrate that the efficient two‐photon polymerization of stable 3D microarchitectures can be achieved using triazole‐based photoinitiators.
Inkjet Printing of Perovskites for Breaking Performance–Temperature Tradeoffs in Fabric‐Based Thermistors
Authors: Li Shujie , Kosek Alex , Jahangir Mohammad Naim , Malhotra Rajiv , Chang Chih‐Hung
Published: September 2020

A novel low‐temperature route is developed for inkjet printing of the perovskite Cs2SnI6, to create wearable negative‐temperature‐coefficient thermistors with unprecedented performance on thermally sensitive fabrics. A low processing temperature of 120 °C is achieved by creating a stable and printable ink using binary metal iodide salts, which is thermally transformed into dense Cs2SnI6 crystals after printing. The optimally printed Cs2SnI6 shows a temperature measurement range up to 120 °C, high sensitivity (4400 K), and temperature coefficient of resistivity (0.05 °C−1), and stability under ambient environmental conditions and bending. The approach breaks a critical tradeoff that has hindered wearable fabric‐based thermistors by enabling damage‐free fabrication of devices with commercially comparable performance, evincing significant applications in multifunctional textiles and beyond.
Jamming Skins that Control System Rigidity from the Surface
Authors: Shah Dylan S. , Yang Ellen J. , Yuen Michelle C. , Huang Evelyn C. , Kramer‐Bottiglio Rebecca
Published: September 2020

Numerous animals adapt their stiffness during natural motions to increase efficiency or environmental adaptability. For example, octopuses stiffen their tentacles to increase efficiency during reaching, and several species adjust their leg stiffness to maintain stability when running across varied terrain. Inspired by nature, variable‐stiffness machines can switch between rigid and soft states. However, existing variable‐stiffness systems are usually purpose‐built for a particular application and lack universal adaptability. Here, reconfigurable stiffness‐changing skins that can stretch and fold to create 3D structures or attach to the surface of objects to influence their rigidity are presented. These “jamming skins” employ vacuum‐powered jamming of interleaved, discrete planar elements, enabling 2D stretchability of the skin in its soft state. Stretching allows jamming skins to be reversibly shaped into load‐bearing, functional tools on‐demand. Additionally, they can be attached to host structures with complex curvatures, such as robot arms and portions of the human body, to provide support or create a mold. We also show how multiple skins can work together to modify the workspace of a continuum robot by creating instantaneous joints. Jamming skins thus serve as a reconfigurable approach to creating tools and adapting structural rigidity on‐demand.
Microfluidic Biomaterials
Authors: Tien Joe , Dance Yoseph W.
Published: September 2020

Since their initial description in 2005, biomaterials that are patterned to contain microfluidic networks (“microfluidic biomaterials”) have emerged as promising scaffolds for a variety of tissue engineering and related applications. This class of materials is characterized by the ability to be readily perfused. Transport and exchange of solutes within microfluidic biomaterials is governed by convection within channels and diffusion between channels and the biomaterial bulk. Numerous strategies have been developed for creating microfluidic biomaterials, including micromolding, photopatterning, and 3D printing. In turn, these materials have been used in many applications that benefit from the ability to perfuse a scaffold, including the engineering of blood and lymphatic microvessels, epithelial tubes, and cell‐laden tissues. This article reviews the current state of the field and suggests new areas of exploration for this unique class of materials.
Advances in the Design of 3D‐Structured Electrode Materials for Lithium‐Metal Anodes
Authors: Park Sunwoo , Jin Hyoung‐Joon , Yun Young Soo
Published: September 2020

Although the lithium‐metal anode (LMA) can deliver a high theoretical capacity of ≈3860 mAh g−1 at a low redox potential of −3.040 V (vs the standard hydrogen electrode), its application in rechargeable batteries is hindered by the poor Coulombic efficiency and safety issues caused by dendritic metal growth. Consequently, careful electrode design, electrolyte engineering, solid‐electrolyte interface control, protective layer introduction, and other strategies are suggested as possible solutions. In particular, one should note the great potential of 3D‐structured electrode materials, which feature high active specific surface areas and stereoscopic structures with multitudinous lithiophilic sites and can therefore facilitate rapid Li‐ion flux and metal nucleation as well as mitigate Li dendrite formation through the kinetic control of metal deposition even at high local current densities. This progress report reviews the design of 3D‐structured electrode materials for LMA according to their categories, namely 1) metal‐based materials, 2) carbon‐based materials, and 3) their hybrids, and allows the results obtained under different experimental conditions to be seen at a single glance, thus being helpful for researchers working in related fields.
Expandable Polymer Assisted Wearable Personalized Medicinal Platform
Authors: Babatain Wedyan , Gumus Abdurrahman , Wicaksono Irmandy , Buttner Ulrich , El‐atab Nazek , Rehman Mutee Ur , Qaiser Nadeem , Conchouso David , Hussain Muhammad Mustafa
Published: September 2020

Conventional healthcare, thoughts of treatment, and practice of medicine largely rely on the traditional concept of one size fits all. Personalized medicine is an emerging therapeutic approach that aims to develop a therapeutic technique that provides tailor‐made therapy based on everyone’s individual needs by delivering the right drug at the right time with the right amount of dosage. Advancement in technologies such as wearable biosensors, point‐of‐care diagnostics, microfluidics, and artificial intelligence can enable the realization of effective personalized therapy. However, currently, there is a lack of a personalized minimally invasive wearable closed‐loop drug delivery system that is continuous, automated, conformal to the skin, and cost‐effective. Here, design, fabrication, optimization, and application of a personalized medicinal platform augmented with flexible biosensors, heaters, expandable actuator and processing units powered by a lightweight battery are shown. The platform provides precise drug delivery and preparation with spatiotemporal control over the administered dose as a response to real‐time physiological changes of the individual. The system is conformal to the skin, and the drug is transdermally administered through an integrated microneedle. The developed platform is fabricated using rapid, cost‐effective techniques that are independent of advanced microfabrication facilities to expand its applications to low‐resource environments.
Roll‐to‐Roll (R2R) Production of Large‐Area High‐Performance Piezoelectric Films Based on Vertically Aligned Nanocolumn Forests
Authors: Yildirim Armen , Grant Jesse C. , Shams Es‐haghi Siamak , Lee Wojae , Maruthamuthu Murali Kannan , Verma Mohit , Sutherland John W. , Cakmak Mukerrem
Published: September 2020

The recent advances in flexible piezoelectric technologies have sparked a great interest in developing multifunctional next‐generation transducers, which are in high demand for various challenging applications. Here, novel quasi 1–3 piezoelectric films with record‐high piezoelectric voltage coefficients (g33), reaching up to 0.709 Vm N−1, ≈20% greater than the recently reported highest g33 value in the literature, are reported. These composites are constructed via dielectrophoretic alignment of lead zirconate titanate (PZT) particles enhanced by graphene nanoplatelets, leading to densely structured cone‐shaped nanocolumn forests in the thickness direction. To demonstrate its potential applications, both structured and randomly dispersed samples are characterized and used in various applications ranging from energy harvesting to structural and personal health monitoring. Furthermore, when placed on the sensor surface, the oriented piezoelectric films are shown to detect even the slight movements of a small‐sized insect, demonstrating the ultrasensitivity of the system. Finally, to show the scalability of the dielectrophoretic process, a large area sample (12 ft long and 6‐in.‐wide) is also produced continuously via a novel multifunctional custom designed roll‐to‐roll manufacturing line. To the best of the knowledge, this is the largest single piece of piezoelectric film ever reported in the literature.
Numerical Development of Concentric Cylinder‐Shaped Dual‐Functional Catalyst Structure for Enhanced Charge Transport in Polymer Electrolyte Fuel Cells
Authors: Shin Seungho , Liu Jiawen , Chung Sung‐Jae , Um Sukkee
Published: September 2020

Dual‐functional catalyst bilayers of vertical concentric cylinders are proposed and numerically developed using a stochastic modeling approach to improve catalyst utilization for advanced fuel cell applications. A cylindrically bilayered catalyst structure wherein the ion transport materials are confined by concentric outer carbon shells is adopted to increase the number of interconnected electron and ion transport paths. For reliable statistical analysis, each data point is extracted from a set of 25 catalyst layer models to achieve a 95% confidence level. The nanoscale morphologies of the ionomers, including interconnected ion transport networks, surface coverage, and electrochemically active surface areas, are quantitatively evaluated. The statistical investigations reveal that the bilayered cylindrical catalyst structures provide more uniform and improved transport paths for ions and reactants when compared with established catalyst layers. Specifically, the additional ion transport channels in the core of the concentric vertical cylinder enhance catalyst utilization under insufficient ionomer conditions. Furthermore, the bilayered catalyst structures yield remarkably enlarged electrochemically active surface areas, hence facilitating more efficient electron, ion, and reactant transfers to improve catalyst utilization.