bluuebunny/crossref_metadata_2025 huggingface dataset:
Pollutions of the Hyperbaric Breathing Atmosphere
Authors: Kłos Ryszard
Published: September 2017

The Sweedish project codenamed DykSMART was carried out in 2013-2015. The results of this project created the base for for international project #R024 Diving with State Maritime Resources in the Baltic DiveSMART-Baltic of Interreg Baltic Sea Region launched in 2016. The Interreg Baltic Sea Region Programme 2014-2020 supports the integrated territorial development and cooperation for a more innovative, better accessible and sustainable Baltic Sea region. Partners from the countries around the Baltic Sea work together in transnational projects on common key challenges and opportunities. DiveSMART project is dedicated to improved coordination concerning the organizations with emergency divers, in order to be able to handle an international emergency situation: - to be aware of which diving competences are available, and also relevant diving equipment; - common international exercises; - knowledge of education and definitions of various levels of competence; - research & development. The project DiveSMART Baltic has received Flagship status. The article is the first in the planned cycle of articles referring to the tasks realised in the Naval Academy within the framework of DiveSMART project. This article presents a review of pollutants of the hyperbaric breathing agent in connection with their toxic action. This subject is linked to the work package four of the DiveSMART project Risk reduction - develop and enhance methods for life support systems of distressed persons in both physical and psychological areas.
Thermal Comfort Properties of Bi-layer Knitted Fabric structure for Volleyball Sportswear
Authors: Suganthi Thangamuthu , Senthilkumar Pandurangan , Dipika Venugopal
Published: September 2017

The thermal comfort properties of different knitted fabric structures made from modal, polypropylene and micro denier polyester were studied for volleyball sportswear. Eleven knitted fabrics were produced, in which three samples were single jersey, two plated and six bi-layer knitted structures. The air permeability, water vapour permeability, thermal conductivity, wicking and drying ability of bi-layer knitted fabric made up of polypropylene as the inner layer and modal as the outer layer with one tuck point of repeat were found to be higher as compared to other bi-layer, plated and single jersey structures. Both theobjective and subjective results show that bi-layer knitted fabric with polypropylene as the inner layer and modal as the outer layer with one tuck point of repeat is mostly suitablefor sportswear. The results are discussed together with multivariate ANOVA test results ata 95% significance level.
Conservação das espécies vegetais em paleoambientes dunares na APA Dunas e Veredas do Baixo-Médio São Francisco, Bahia, Brasil
Authors: Pacheco Clecia Simone Gonçalves Rosa , Oliveira Niédja Maria Galvão Araújo
Published: September 2017

Apesar do avanço do conhecimento científico que se tem atualmente, com dados sobre a flora e sua respectiva distribuição, esse ainda não é completo e não permite que se prescinda da experiência de campo, intraduzível em termos de determinação da composição florística e características das plantas e do meio.  Mediante tal pressuposto, este artigo objetiva demonstrar o levantamento das espécies vegetais realizado na Área de Proteção Ambiental (APA) Dunas e Veredas do Baixo-Médio São Francisco, e sua relevância para a manutenção do equilíbrio ecológico do paleo-ecossistema dunar.  É possível afirmar que a vegetação é o espelho do clima e, sendo o espelho do clima, percebe-se que algumas espécies encontradas representam a fisionomia dos climas atuais, mas podendo indicar resquícios de paleoclimas. Desta maneira, a vegetação é vista coma à chave da manutenção do equilíbrio dinâmico do ecossistema e sua preservação é defendida por esta razão. Trata-se de uma pesquisa qualitativa e de cunho exploratório, onde fundamentou-se a priori em teóricos que abordam sobre tal temática e, em seguida utilizou-se o Método de Caminhamento introduzido por Filgueiras et al., (1994) sendo que, o uso deste, tem se mostrado eficiente para elaborar o levantamento qualitativo de grande parte da variabilidade florística em diferentes fitofisionomias. A pesquisa in loco possibilitou a identificação de várias espécies exóticas, endêmicas e, nativas da região semiárida, além de outras típicas de áreas mais úmidas (Floresta Amazônica, Floresta Atlântica e Áreas de Transições). Portanto, os resultados indicam a urgência da criação de planos estratégicos de conservação da diversidade florística da área dunar, tendo em vista que os vegetais ali presentes, são responsáveis pela estabilização das areias eólicas dos campos, e sem estas, consequentemente ter-se-á o agravamentos dos processos de degradação ambiental já evidente na área.
Educação ambiental: o papel das mulheres na preservação do ambiente
Authors: Rosa Valdilene Monteiro , Sousa Katiúcia Freitas , Szulczewski Nívia Alves Sales , Carvalho Aluísio Vasconcelos de
Published: September 2017

A presente pesquisa tem como objetivo discutir sobre o papel das mulheres na preservação do ambiente demonstrando o vínculo em que ela desenvolve com a natureza. Neste sentido, o trabalho confirma algumas informações importantes na relação entre mulher e natureza, direitos que garantam a inclusão do gênero em várias questões sociais, culturais e ambientais. Podemos apontar, entretanto, que a relação de proximidade com o tema ambiental, a mulher está, na maioria das vezes, longe do processo de tomada de decisão em relação às políticas ambientais. Sendo assim, este artigo permite uma melhor compreensão das relações que as mulheres estabelecem com a natureza, no material,  social e cultural, o que mostra a importância do seu papel na preservação do ambiente.
Is the Public Good Role of Higher Education Under Attack?
Authors: Hazelkorn Ellen
Published: September 2017

Higher education has long argued that it is a public good because of its contributionto societal goals. These assumptions are coming under growing public scrutiny asuniversities seek to pursue their own agenda, at home and increasinglyinternationally. This article looks at some of the issues.
“Free Speech” and “Offensive” Speech on Campus
Authors: Scott Peter
Published: September 2017

Debates about free speech and academic freedom—and their limits—have become sharper but also more confused. Conservatives demand greater restrictions, but so too do radicals worried that offensive speech may disrupt campus communities. Universities have a special responsibility to secure the right balance between free expression and offensive speech.
Postsecondary Systems, Massification, and the Research University
Authors: Altbach Philip G.
Published: September 2017

In the context of massification, few countries have made any comprehensive effort to create clearly defined and differentiated academic systems to serve new academic functions. This pursuit is important to ensure quality and to meet the wide range of needs of an increasingly diverse student population.
Armenia: Cross-Border Higher Education
Authors: Gharibyan Tatevik
Published: September 2017

After independence in 1991, the higher education sector in Armenia started to reshapeautonomously. Many private and transnational educational institutions started to appear on theArmenian educational market and cross-border education gained a tangible popularity. Thisarticle surveys existing cross-border educational institutions in the country and their impact onthe educational landscape.
Higher Education in Mauritius: Challenges and Perspectives of Internationalization
Authors: Motala Timol Shaheen , Kinser Kevin
Published: September 2017

Since 2000, Mauritius has had a policy to become a knowledge hub, with internationalization of its higher education sector as a key initiative. The country had several difficulties in implementing this plan, and based on this experience is now reviewing its efforts and policies to address the issues encountered. This case offers several lessons to understand how an internationalization agenda can be implemented as an element of a diversified economy.
Higher Education Internationalization in Ukraine: Concerns and Hope
Authors: Sikorskaya Irina
Published: September 2017

Internationalization is gradually becoming integrated into the core functions ofUkrainian higher education institutions. Recent developments at the international andnational levels are conducive to enhancing and intensifying the process, but a numberof challenges still prevent it from progressing substantially. There is a call to make aquality shift in embracing internationalization.
Free Higher Education: Mistaking Equality and Equity
Authors: De Gayardon Ariane
Published: September 2017

Free higher education is seeing a revival of popularity globally at a time whenstudents and their families are asked to contribute ever more toward the cost of college.However, contrary to popular belief, free-tuition higher education is not necessarilyassociated with better access to, or equity within, tertiary education. This article takes acloser look at the realities behind “free” higher education, more specifically in itsrelationship with access.
The Emergence (and Perils) of Income-Targeted Free Tuition
Authors: Usher Alex
Published: September 2017

Free tuition has been implemented in many contexts, but is differently targeted, and can become more expensive and less effective than the policies it seeks to replace. New York, Chile, and Canada’s plans are highlighted in this article.
Public Universities and Budget Cuts in Malaysia
Authors: Abdullah Doria
Published: September 2017

Malaysian public universities have experienced drastic budget cuts over the past twoyears, which did not bode well for Malaysia’s academic community. This articlepresents an overview of the situation, explaining the rationales behind the budgetcuts, adjustments made by public universities, and unaddressed gaps.
Another Missed Opportunity? Underfunding Australian Higher Education
Authors: Welch Anthony
Published: September 2017

In the context of a long period of underfunded highereducation in Australia, the latest federal budget will do nothing to address theproblem. While the worst elements of former proposals were averted, the shifting ofmore of the burden of repaying student loans on to students, as well as failing tofund the full costs of research, and, in addition, imposing further “‘efficiencydividends”’ on higher education institutions, will only add to institutionalpressures to diversify income, increasing international student fees.
Tempest in the Rankings Teapot: An African Perspective
Authors: Teferra Damtew
Published: September 2017

According to the Times Higher Education, “the reputation league table is based on nothing more than subjective judgment.” QS also states that 60 percent of its scores are dependent on reputation, thus subjective. What is depressingly astonishing, however, is how seriously the world of higher education (and beyond) takes these self-serving businesses, which use defective and flawed instruments year in and year out. This piece provides yet another evidence on their utter failure in their purported role as gatekeepers of quality.
Research: The “Lost Mission” of African Universities
Authors: Andoh Harris
Published: September 2017

The first universities in Africa were established with the triple mission of teaching,research, and community engagement. Yet, many university leaders hold the mistaken notion that theiruniversities have always been research universities. It is only over the last decadethat the research mission has emerged again as a key vision of African universities.
India: World-Class Universities?
Authors: Altbach Philip G. , Salmi Jamil
Published: September 2017

India’s higher education and research sectors have been generallyunderfunded, especially in view of the tremendous growth in numbers ofstudents. Compared to the other BRIC countries, the percentage spent oneducation, 4.1 percent of GDP, is second to Brazil. This article explores the Indian higher education system with respect to its potential to create world-class universities.
Enough Quantity: Time to Focus on Quality of Researchers in Pakistan
Authors: Ahmed Muhammad
Published: September 2017

The education sector of Pakistan has progressed tremendously during the last 15 years,with the number of researchers and research papers increasing by 248 percent and 687percent respectively. However, the quality of Pakistani research is still of uneven quality,partly due to the inexperience, incompetence, and corruption of faculty at nationalhigher education institutions. Revising faculty hiring criteria, establishing a plagiarism-free research culture, enhancing training on research ethics, and involving morePakistani scholars trained abroad in research are key steps toward preserving highereducation in Pakistan.
Student Diversity and Challenges of Inclusion in Higher Education in India
Authors: Sabharwal Nidhi S. , Malish C.M.
Published: September 2017

With an enrollment of 34 million students and a gross enrollmentratio passing 24 percent in 2016, India is in a stage of massification. This article addresses challenges surrounding the issue of growing student diversity on higher education campuses.
The Contradictions of Private Higher Education Expansion in India
Authors: Mathews Eldho
Published: September 2017

When it comes to university-level education in India, a majority of students and parents prefer government and government-aided private institutions, as contrasted with the strong presence of private providers at the primary and secondary levels. This article explores the range of providers at the tertiary level.
The Cultural Mission of Premier Universities in East Asia
Authors: Yang Rui
Published: September 2017

Over the past few decades East Asia has made remarkable progress in highereducation development in both quantity and quality. Yet, an assessment regarding itsfuture development is less certain. Adopting a cultural perspective, this article reportssome findings from a recent research project financed by the Hong Kong ResearchGrants Council. It argues that the gap between Western and East Asian ideas of auniversity is narrowing. East Asian premier universities are making a cultural experimentto achieve an integration of both. Their efforts have global significance.
The Slow Path to General Education in Chinese Universities
Authors: Dunrong Bie
Published: September 2017

In recent years, many Chineseuniversities have launched general educationprograms. This piece explores the history of general education in China and outlines innovative gen ed programs in development.
New “Startups” in a Rigid Higher Education System: China’s Young Elite Institutions
Authors: Wu Hantian
Published: September 2017

This article focuses on three young, small-scale elite institutions in mainland China,established during the last decade: SUSTech, ShanghaiTech, and Westlake Institutefor Advanced Study, the foundation of the future Westlake University. By analyzingthe similarities and differences between these institutions in terms of developmentstrategies, funding models, and admission policies, it discusses whether theestablishment of such young elite institutions can be regarded as a bottom-upinnovation in Chinese higher education or a new utilitarian choice made by municipalgovernments and higher education practitioners.
How long should the fully hillside-closed forest protection be implemented on the Loess Plateau, Shaanxi, China?
Authors: Hou Lin , Hou Sijia
Published: September 2017

Background

Restoration of degraded forest ecosystem is crucial for regional sustainable development. To protect the country’s fragile and fragmented environment, the Chinese government initiated an ecological engineering project, the Natural Forest Protection Program, in seventeen provinces in China beginning in 1998. Fully hillside-closed forest protection (vegetation restoration naturally without any artificial disturbance) was one of vital measures of the Natural Forest Protection Program applied nation wide. Whether plant diversity, biomass and age structure of dominant tree species and soil nutrients in protected stands may become better with increase of protected period are still open problems.

Methods

We investigated community diversity, biomass of dominant tree species, age structures, and analyzed soil chemical properties of a Pinus tabulaeformis population at protected sites representing different protected ages at Huanglongshan Forest Bureau on the Loess Plateau, Shaanxi, China.

Results

Plant species richness of Pinus tabulaeformis community was significantly affected (p < 0.05) by forest protection and the effect attenuated with protection age. Shannon evenness index of plant species generally increased with protection age. Stands protected for 45 years had the highest tree biomass and considerable natural regeneration capacity. Contents of organic carbon, available phosphorus and available potassium in top soil increased in protected stands less than 45 years, however decreased significantly thereafter. Long-term forest protection also decreased the content of mineral nitrogen in top soil.

Discussion

We found that the richness of shrubs and herbs was significantly affected by forest protection, and evenness indices of tree, shrub and herb increased inconsistently with protected ages. Forest protection created more complex age structures and tree densities with increasing age of protection. Content of soil mineral nitrogen at 0–20 cm soil depth showed a decreasing trend in stands of up to 30 years. Soil available phosphorus and potassium contents were higher in stands with greater proportions of big and medium trees. Long-term protection (>45 years) of Pinus tabulaeformis stands in southeast Loess Plateau, China, may be associated with decreasing plant species richness, proportion of medium to large trees, dominant biomass of Pinus tabulaeformis and soil nutrients.
Global and Brazilian Carbon Response to El Niño Modoki 2011–2010
Authors: Bowman K. W. , Liu J. , Bloom A. A. , Parazoo N. C. , Lee M. , Jiang Z. , Menemenlis D. , Gierach M. M. , Collatz G. J. , Gurney K. R. , Wunch D.
Published: September 2017

The El Niño Modoki in 2010 led to historic droughts in Brazil. In order to understand its impact on carbon cycle variability, we derive the 2011–2010 annual carbon flux change (δF↑) globally and specifically to Brazil using the NASA Carbon Monitoring System Flux (CMS‐Flux) framework. Satellite observations of CO2, CO, and solar‐induced fluorescence (SIF) are ingested into a 4D‐variational assimilation system driven by carbon cycle models to infer spatially resolved carbon fluxes including net ecosystem production, biomass burning, and gross primary productivity (GPP). The global 2011–2010 net carbon flux change was estimated to be δF↑=−1.60 PgC, while the Brazilian carbon flux change was −0.24 ± 0.11 PgC. This estimate is broadly within the uncertainty of previous aircraft‐based estimates restricted to the Amazon basin. The 2011–2010 biomass burning change in Brazil was −0.24 ± 0.036 PgC, which implies a near‐zero 2011–2010 change of the net ecosystem production (NEP): The near‐zero NEP change is the result of quantitatively comparable increases GPP (0.31 ± 0.20 PgC) and respiration in 2011. Comparisons between Brazilian and global component carbon flux changes reveal complex interactions between the processes controlling annual land‐atmosphere CO2 exchanges. These results show the potential of multiple satellite observations to help quantify and spatially resolve the response of productivity and respiration fluxes to climate variability.
Statistical Characteristics of Convective Clouds over the Western Ghats Derived from Weather Radar Observations
Authors: Utsav Bhowmik , Deshpande Sachin M. , Das Subrata K. , Pandithurai Govindan
Published: September 2017

X‐band radar observations at Mandhardev (18.04°N, 73.85°E) are used to investigate statistics of convective clouds over the Western Ghats during monsoon season (June–September 2014). Convective storms (cells) are identified using an objective‐tracking method to examine their spatiotemporal variability, thus quantifying the time‐continuous aspects of convective cloud population over the region for the first time. An increased frequency of storm location and initiation along the windward mountains compared to coastal and lee side highlights orographic response to southwesterly flow, with superimposed diurnal cycle. An eastward progression of convective activity from upstream the barrier through windward slopes of mountains over to the lee side is observed. Storm area, height, and duration follow lognormal distributions; wherein, small‐sized storms contribute more to total population and unimodal distribution of 35 dBZ top heights (peaking at 5.5 km) depicts the dominance of shallow convection. Storms exhibit a pronounced diurnal cycle with a peak in afternoon hours, while the convective area maximum is delayed by several hours to that of precipitation flux. Cell lifetime and propagation show that cells move with slow speeds and have mean duration of 46 min. They align east‐west nearly parallel to mountain ridges, and their direction of movement is steered mostly by large‐scale winds at lower levels. Based on top heights, convective cells are further classified into cumulus, congestus, and deep clouds. In general, congestus (deep) cells are most abundant in the windward (leeward) side. A lead‐lag relationship between congestus and deep cells indicates midtroposphere moistening by congestus cells prior to deep convection.
Resolving the Model‐Observation Discrepancy in the Mesospheric and Stratospheric HOx Chemistry
Authors: Li King‐Fai , Zhang Qiong , Wang Shuhui , Sander Stanley P. , Yung Yuk L.
Published: September 2017

We examine the middle atmospheric odd‐hydrogen (HOx) chemistry by comparing the Aura Microwave Limb Sounder (MLS) OH and HO2 measurements with a photochemical model simulation. The model underestimates mesospheric OH and HO2 concentrations if the standard chemical kinetic rates are used, whether the model H2O and O3 are constrained with observations or not. To resolve the discrepancies, we adjust the kinetic rate coefficients of three key reactions (O + OH → O2 + H, OH + HO2 → H2O + O2, and H + O2 + M → HO2 + M) and the O2 photo absorption cross section at Lyman α (121.57 nm) using the Bayesian optimal estimation. A much better model‐observation agreement can be achieved if the kinetic rate coefficients for H + O2 + M → HO2 + M is increased by 134–310%, and the O2 photo absorption cross section at Lyman α is reduced by 33–54%, while the kinetic rate coefficients for O + OH → O2 + H and OH + HO2 → H2O + O2 remain consistent with the current laboratory values. The kinetic rate coefficient for H + O2 + M → HO2 + M requires a very large adjustment beyond the uncertainty limits recommended in the NASA Data Evaluation, suggesting the need for future laboratory measurements. An alternative explanation is that the radiative association reaction, H + O2 → HO2 + hν, plays a significant role, which has never been measured. Our results demonstrate that high‐quality satellite observations can be used to constrain photochemical parameters and help improve our understanding of atmospheric chemistry.
Post‐translational modifications of Arabidopsis E3 SUMO ligase AtSIZ1 are controlled by environmental conditions
Authors: Kim Joo Yong , Song Jong Tae , Seo Hak Soo
Published: September 2017

Sumoylation regulates numerous cellular functions in plants as well as in other eukaryotic systems. However, the regulatory mechanisms controlling E3 small ubiquitin‐related modifier (SUMO) ligase are not well understood. Here, post‐translational modification of the Arabidopsis E3 SUMO ligase AtSIZ1 was shown to be specifically controlled by abiotic stresses. AtSIZ1 ubiquitination was induced by exposure to heat stress in transgenic plants overexpressing the E3 ubiquitin ligase COP1. In addition, AtSIZ1 ubiquitination was strongly enhanced in transgenic plants overexpressing SUMO isopeptidase ESD4 under heat stress. By contrast, drought stress induced sumoylation rather than ubiquitination of AtSIZ1 and sumoylated forms of AtSIZ1 accumulated in esd4 and cop1–4 mutants. Moreover, siz1 mutants were found to be tolerant to heat and drought stresses. Taken together, these results indicate that ubiquitination and sumoylation of AtSIZ1 in response to abiotic stresses depend on the activities of COP1 and ESD4 and that the activity and stability of AtSIZ1 can be specifically controlled by different abiotic stresses.
Deep sequencing and comprehensive expression analysis identifies several molecules potentially related to human poorly differentiated hepatocellular carcinoma
Authors: Shao Ping , Sun Deguang , Wang Liming , Fan Rong , Gao Zhenming
Published: September 2017

Hepatocellular carcinoma (HCC) that is graded histologically as poorly differentiated has a high recurrence, metastasis and poor prognosis. We sought to determine the regulatory mechanisms of HCC tumorigenesis and to identify molecules closely related to poorly differentiated HCC. High‐throughput sequencing was used to construct microRNA (miRNA) and mRNA expression profiles for poorly differentiated HCC tissues and adjacent tissues. Network analysis was carried out to study miRNA–target interactions. Integrating the miRNA and mRNA data of HCC with four tumor grades from The Cancer Genome Atlas (TCGA) portal enabled the identification of potential closely related molecules for early diagnosis of poorly differentiated HCC. Electronic validation of RNA‐seq data and survival analysis was also performed. In total, 1051 differentially expressed genes and 165 differentially expressed miRNAs were identified between HCC tumor and paired non‐tumorous tissue. Based on 3718 miRNA–target interactions, we established an miRNA–target interaction network; the target genes were mainly involved in bile acid biosynthesis and bile secretion. Integrating expression data of HCC from TCGA indicated that two proteins, TM4SF1 and ANXA2, are convincing indicators for initial diagnosis of poorly differentiated HCC. According to the survival analysis, three proteins, ANXA2, C8orf33 and IGF2BP3, were identified as being associated with the survival time of HCC patients. Moreover, we suggest that hsa‐miR‐1180 may be an effective biomarker for poorly differentiated HCC. Three molecules, TM4SF1, ANXA2 and C8orf33, are potential biomarkers for distinguishing poorly differentiated from well‐differentiated HCC.
Photonic Sensing of Reactive Atmospheric Species
Authors: Chen Weidong , Yi Hongming , Wu Tao , Zhao Weixiong , Lengignon Christophe , Wang Gaoxuan , Fertein Eric , Coeur Cécile , Wysocki Gerard , Wang Tao , Sigrist Markus W. , Gao Xiaoming , Zhang Weijun
Published: September 2017

Chemically reactive short‐lived atmospheric species play a crucial role in tropospheric processes that affect regional air quality and global climate change. Contrary to long‐lived species (such as greenhouse gases), fast, interference‐free, accurate, and precise in situ monitoring of such strongly reactive species represents a real challenge owing to their very high reactivity resulting in short lifetimes (∼1–100 s) and ultralow concentrations (∼pptv). In this article, we give an overview of the recent progress in the development of absorption spectroscopy‐based photonic instruments involving modern photonic light sources (quantum cascade laser, distributed feedback diode laser, and light‐emitting diode) combined with high‐sensitivity spectroscopic measurement techniques such as incoherent broadband cavity‐enhanced absorption spectroscopy, Faraday rotation spectroscopy, wavelength‐modulation‐enhanced off‐axis integrated cavity output spectroscopy, tuning fork‐ or microphone‐based photoacoustic spectroscopy, and open‐path multipass absorption spectroscopy. Illustrative examples of monitoring some key atmospheric reactive species (such as HONO, OH, NO3, N2O5, and NO2) will be presented for applications in intensive field campaigns, instrumented atmospheric simulation chamber, or laboratory investigation.
Reticulated Replica Ceramic Foams: Processing, Functionalization, and Characterization
Authors: Fey Tobias , Betke Ulf , Rannabauer Stefan , Scheffler Michael
Published: September 2017

Reticulated ceramic foams are used in a wide range of applications such as filters, catalyst supports, lightweight materials, energy absorptions materials, or as scaffolds for tissue engineering as the most common ones. Based on gaseous foaming processes of polymers, a stochastic distribution of closed pores is obtained. By reticulation processing thin foam windows are removed between cells turning a closed cell into an open cell structure. These foams are used as template for porous ceramics manufacturing: With different processing approaches, for example, with dip coating of a ceramic slurry and a subsequent (multistep) thermal treatment ceramic reticulate foams are obtained. A variety of material properties strongly depend on the cell and strut size, as well on material composition. Functionalization of ceramic foam surfaces (outer surface functionalization), for example, with zeolites or nanosized aggregates lead to an increase of the specific surface area or provides catalytic or heat storage functionality. Filling of struts (inner surface functionalization) may lead to improved mechanical stability or may provide functionalities such as electric conductivity. The present work summarizes the processing steps from the template foam to the final cellular ceramic, functionalization strategies, and the most common characterization techniques.
Engineered Axonal Tracts as “Living Electrodes” for Synaptic‐Based Modulation of Neural Circuitry
Authors: Serruya Mijail D. , Harris James P. , Adewole Dayo O. , Struzyna Laura A. , Burrell Justin C. , Nemes Ashley , Petrov Dmitriy , Kraft Reuben H. , Chen H. Isaac , Wolf John A. , Cullen D. Kacy
Published: September 2017

Brain–computer interface and neuromodulation strategies relying on penetrating non‐organic electrodes/optrodes are limited by an inflammatory foreign body response that ultimately diminishes performance. A novel “biohybrid” strategy is advanced, whereby living neurons, biomaterials, and microelectrode/optical technology are used together to provide a biologically‐based vehicle to probe and modulate nervous‐system activity. Microtissue engineering techniques are employed to create axon‐based “living electrodes”, which are columnar microstructures comprised of neuronal population(s) projecting long axonal tracts within the lumen of a hydrogel designed to chaperone delivery into the brain. Upon microinjection, the axonal segment penetrates to prescribed depth for synaptic integration with local host neurons, with the perikaryal segment remaining externalized below conforming electrical–optical arrays. In this paradigm, only the biological component ultimately remains in the brain, potentially attenuating a chronic foreign‐body response. Axon‐based living electrodes are constructed using multiple neuronal subtypes, each with differential capacity to stimulate, inhibit, and/or modulate neural circuitry based on specificity uniquely afforded by synaptic integration, yet ultimately computer controlled by optical/electrical components on the brain surface. Current efforts are assessing the efficacy of this biohybrid interface for targeted, synaptic‐based neuromodulation, and the specificity, spatial density and long‐term fidelity versus conventional microelectronic or optical substrates alone.
A Mesocrystal‐Like Morphology Formed by Classical Polymer‐Mediated Crystal Growth
Authors: Smeets Paul J. M. , Cho Kang Rae , Sommerdijk Nico A. J. M. , De Yoreo James J.
Published: September 2017

Growth by oriented assembly of nanoparticles is a widely reported phenomenon for many crystal systems. While often deduced through morphological analyses, direct evidence for this assembly behavior is limited and, in the calcium carbonate (CaCO3) system, has recently been disputed. However, in the absence of a particle‐based pathway, the mechanism responsible for the creation of the striking morphologies that appear to consist of subparticles is unclear. Therefore, in situ atomic force microscopy is used to investigate the growth of calcite crystals in solutions containing a polymer additive known for its ability to generate crystal morphologies associated with mesocrystal formation. It is shown that classical growth processes that begin with impurity pinning of atomic steps, leading to stabilization of new step directions, creation of pseudo‐facets, and extreme surface roughening, can produce a microscale morphology previously attributed to nonclassical processes of crystal growth by particle assembly.
Elastic Modulus Dependence on the Specific Adhesion of Hydrogels
Authors: Wang Hanqing , Jacobi Fawad , Waschke Johannes , Hartmann Laura , Löwen Hartmut , Schmidt Stephan
Published: September 2017

Mechanosensitivity in biology, e.g., cells responding to material stiffness, is important for the design of synthetic biomaterials. It is caused by protein receptors able to undergo conformational changes depending on mechanical stress during adhesion processes. Here the elastic modulus dependence of adhesive interactions is systematically quantified using ligand–receptor model systems that are generally not thought to be mechanosensitive: biotin–avidin, mannose–concanavalin A, and electrostatic interactions between carboxylic acids and polycationic surfaces. Interactions are measured by microgel sensors of different stiffness adhering to surfaces presenting a corresponding binding partner. Adhesion is generally decreased for softer microgels due to reduced density of binding partners. Density‐normalized data show that low‐affinity carbohydrate ligands exhibit reduced binding in softer networks, probably due to increased network conformational entropy. However, in case of stronger interactions with large interaction range (electrostatic) and large lifetime (biotin–avidin) density normalized adhesion is increased. This suggests compensation of entropic repulsion for softer networks probably due to their increased mechanical deformation upon microgel adhesion and enhanced cooperative binding. In essence, experiments indicate that soft interacting polymer materials exhibit entropic repulsion, which can be overcome by strongly interacting species in the network harnessing network flexibility in order to increase adhesion.
Self‐Assembling Azaindole Organogel for Organic Light‐Emitting Devices (OLEDs)
Authors: Martín Cristina , Kennes Koen , Van der Auweraer Mark , Hofkens Johan , de Miguel Gustavo , García‐Frutos Eva M.
Published: September 2017

This study reports on the use of a self‐assembling organogel, 5‐(4‐nonylphenyl)‐7‐azaindole (1), as a new emitter in small‐molecule organic light emitting devices (OLEDs). The theoretical calculations along with the photophysical characterization studies suggest the coexistence of the monomer and dimer species at high concentration of compound 1. The presence of this type of dimer (formed via H‐bonding) is responsible for the increased emission. However, the most notable feature is the 3D network of vastly interconnected fibers formed in the organogel that modifies the photophysical properties. Based on this, several OLED architectures are made in order to understand the mechanism involved in the electroluminescence (EL) behavior of 1. Although the position of the EL spectra differs from that of the photoluminescence (PL) spectra, the trends observed in the device properties perfectly match with dimer formation. In this framework a better device performance is associated to a higher efficiency of dimer formation, which optimizes in the OLED prepared from the organogel. Therefore, these results show that the rational combination of a moiety showing a strong PL intensity increased upon aggregation with organogel properties is an efficient strategy to create alternative emitters for OLED devices.
Nanoarchitectonics for Hybrid and Related Materials for Bio‐Oriented Applications
Authors: Ariga Katsuhiko , Leong David Tai , Mori Taizo
Published: September 2017

Atom/molecular‐level controls in nanotechnology are important for the precise placement of components in device applications. Despite many advances, nanotechnology still uses simple systems to make precise atom/molecule‐scale changes. This is in contrast with the many phenomena observed in biological systems, where there appears to be a well‐designed integrative approach involving molecular units to achieve atomic‐ and molecular‐scale changes. Inspired by nature, we introduced a novel concept—nanoarchitectonics—to develop nanoscale functional materials for bio‐oriented applications. Nanoarchitectonics is a unified concept combining nanotechnology and methodologies in related research fields, such as supramolecular chemistry, self‐assembly, and self‐organization, to satisfy the major features of nanosciences for the creation of functional materials or even devices and machines. This concept guides the harmonized assembly of nanoscale objects into higher order functional materials. In this Feature Article, recent research activities are introduced regarding the development of advanced functional materials of hybrid and related architectures on the basis of nanoarchitectonics from diverse contexts of organic and inorganic materials: i) from biology (DNA‐based hybrid); ii) from geology (clay‐based hybrid); iii) from 0D nanotechnology (fullerene‐based hybrid); and iv) from other nanoarchitectonics. Therefore, this Feature Article showcases some examples of the nanoarchitectonic concepts at work in diverse material types.
Highly Efficient Self‐Healable and Dual Responsive Cellulose‐Based Hydrogels for Controlled Release and 3D Cell Culture
Authors: Yang Xuefeng , Liu Guoqiang , Peng Liao , Guo Jinhua , Tao Lei , Yuan Jinying , Chang Chunyu , Wei Yen , Zhang Lina
Published: September 2017

To face the increasing demand of self‐healing hydrogels with biocompatibility and high performances, a new class of cellulose‐based self‐healing hydrogels are constructed through dynamic covalent acylhydrazone linkages. The carboxyethyl cellulose‐graft‐dithiodipropionate dihydrazide and dibenzaldehyde‐terminated poly(ethylene glycol) are synthesized, and then the hydrogels are formed from their mixed solutions under 4‐amino‐DL‐phenylalanine (4a‐Phe) catalysis. The chemical structure, as well as microscopic morphologies, gelation times, mechanical and self‐healing performances of the hydrogels are investigated with 1H NMR, Fourier transform infrared spectroscopy, atomic force microscopy, rheological and compression measurements. Their gelation times can be controlled by varying the total polymer concentration or 4a‐Phe content. The resulted hydrogels exhibit excellent self‐healing ability with a high healing efficiency (≈96%) and good mechanical properties. Moreover, the hydrogels display pH/redox dual responsive sol‐gel transition behaviors, and are applied successfully to the controlled release of doxorubicin. Importantly, benefitting from the excellent biocompatibility and the reversibly cross‐linked networks, the hydrogels can function as suitable 3D culture scaffolds for L929 cells, leading to the encapsulated cells maintaining a high viability and proliferative capacity. Therefore, the cellulose‐based self‐healing hydrogels show potential applications in drug delivery and 3D cell culture for tissue engineering.
Nutlin‐3a and Cytokine Co‐loaded Spermine‐Modified Acetalated Dextran Nanoparticles for Cancer Chemo‐Immunotherapy
Authors: Bauleth‐Ramos Tomás , Shahbazi Mohammad‐Ali , Liu Dongfei , Fontana Flavia , Correia Alexandra , Figueiredo Patrícia , Zhang Hongbo , Martins João Pedro , Hirvonen Jouni T. , Granja Pedro , Sarmento Bruno , Santos Hélder A.
Published: September 2017

The combination of chemo‐ and immunotherapy represents one promising strategy to overcome the existent challenges in the present‐day anticancer therapy. Here, spermine‐modified acetalated dextran nanoparticles (Sp‐AcDEX NPs), co‐loaded with the non‐genotoxic molecule Nutlin‐3a (Nut3a), and the cytokine granulocyte–macrophage colony‐stimulating factor (GM‐CSF), are developed to induce cancer cell death and create a specific antitumor immune response. These polymeric NPs release Nut3a in a pH dependent fashion and induce endosomal escape. Due to Nut3a, the loaded NPs exert specific toxicity toward wild‐type p53 cancer cells while avoiding toxicity in immune cells. Furthermore, the NPs show intrinsic immune adjuvancy on monocyte derived‐dendritic cells, upregulating the expression of cell surface CD83 and CD86 costimulatory markers. Finally, it is examined that by inducing MCF‐7 breast cancer cell death and acting as immune adjuvants, the NPs can downregulate the expression of IL‐10 and upregulate IL‐1β, leading to proliferation of CD3+ and cytotoxic CD8+ T cells. Overall, the study suggests that Sp‐AcDEX NPs loaded with Nut3a and GM‐CSF is a promising system for chemo‐immunotherapy, capable of inducing tumor cell death and stimulating immune response.
Highly Stretchable, Compliant, Polymeric Microelectrode Arrays for In Vivo Electrophysiological Interfacing
Authors: Qi Dianpeng , Liu Zhiyuan , Liu Yan , Jiang Ying , Leow Wan Ru , Pal Mayank , Pan Shaowu , Yang Hui , Wang Yu , Zhang Xiaoqian , Yu Jiancan , Li Bin , Yu Zhe , Wang Wei , Chen Xiaodong
Published: September 2017

Polymeric microelectrode arrays (MEAs) are emerging as a new generation of biointegrated microelectrodes to transduce original electrochemical signals in living tissues to external electrical circuits, and vice versa. So far, the challenge of stretchable polymeric MEAs lies in the competition between high stretchability and good electrode–substrate adhesion. The larger the stretchability, the easier the delamination of electrodes from the substrate due to the mismatch in their Young's modulus. In this work, polypyrrole (PPy) electrode materials are designed, with PPy nanowires integrated on the high conductive PPy electrode arrays. By utilizing this electrode material, for the first time, stretchable polymeric MEAs are fabricated with both high stretchability (≈100%) and good electrode–substrate adhesion (1.9 MPa). In addition, low Young's modulus (450 kPa), excellent recycling stability (10 000 cycles of stretch), and high conductivity of the MEAs are also achieved. As a proof of concept, the as‐prepared polymeric MEAs are successfully used for conformally recording the electrocorticograph signals from rats in normal and epileptic states, respectively. Further, these polymeric MEAs are also successful in stimulating the ischiadic nerve of the rat. This strategy provides a new perspective to the highly stretchable and mechanically stable polymeric MEAs, which are vital for compliant neural electrodes.
Efficient Heterogeneous Gold(I)‐Catalyzed Direct C(sp2)–C(sp) Bond Functionalization of Arylalkynes through a Nitrogenation Process to Amides
Authors: Nie Quan , Yi Feiyan , Huang Bin , Cai Mingzhong
Published: September 2017

The first heterogeneous gold(I)‐catalyzed direct C(sp2)–C(sp) bond functionalization of arylalkynes through a nitrogenation process to amides has been achieved by using an ordered mesoporous silica (MCM‐41)‐immobilized phosphine gold(I) complex [MCM‐41‐PPh3‐AuCl] as catalyst and silver carbonate (Ag2CO3) as cocatalyst with trimethylsilyl azide (TMSN3) as a nitrogen source, yielding a variety of amides in moderate to excellent yields under mild conditions. This heterogeneous phosphine gold(I) complex shows the same turnover numbers as the homogeneous chloro(triphenylphosphine)gold(I) (Ph3PAuCl) and can easily be recovered by simple filtration of the reaction solution and recycled at least eight times without significant loss of activity, providing a novel, efficient, practical and economic method for the synthesis of amides from alkynes.

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Silk‐Based Fine Dust Filters for Air Filtration
Authors: Jokisch Stephan , Neuenfeldt Martin , Scheibel Thomas
Published: September 2017

State‐of‐the‐art air filter devices have been well‐characterized and optimized for particle deposition of a huge range of particle sizes. However, sustainability of the employed filter materials is usually neglected. In this study, several polymers (recombinant spider silk, recombinant lacewing silk, poly(lactic acid), and poly(ethylene oxide)) are electrospun into fine dust filter layers to evaluate relevant filter parameters such as particle deposition, air permeability, and pressure drop for sub‐micrometer fiber materials. Filters comprising silk proteins show a much lower demand on fine‐dust‐layer material (40–210 mg m−2) in comparison to that of conventional filters (50 g m−2). Filters equipped with silk meshes with fiber diameters in the sub‐micrometer regime (<250 nm) show improved filter qualities in comparison to that of commercially available air filter devices (with melt blown fibers in the >20 µm regime). In particular, sub‐micrometer particles (0.2–1 µm) are filtered more efficiently by the silk‐based filters due to interception and impaction effects yielding a low pressure drop, and therefore these filters show an improved air permeability and lowered pressure drop of, for example, a vacuum cleaner bag in which they can be employed.
Single‐Atom to Single‐Atom Grafting of Pt1 onto FeN4 Center: Pt1@FeNC Multifunctional Electrocatalyst with Significantly Enhanced Properties
Authors: Zeng Xiaojun , Shui Jianglan , Liu Xiaofang , Liu Qingtao , Li Yongcheng , Shang Jiaxiang , Zheng Lirong , Yu Ronghai
Published: September 2017

Nonprecious metal catalysts (NPMCs) FeNC are promising alternatives to noble metal Pt as the oxygen reduction reaction (ORR) catalysts for proton‐exchange‐membrane fuel cells. Herein, a new modulation strategy is reported to the active moiety FeN4 via a precise “single‐atom to single‐atom” grafting of a Pt atom onto the Fe center through a bridging oxygen molecule, creating a new active moiety of Pt1O2Fe1N4. The modulated FeNC exhibits remarkably improved ORR stabilities in acidic media. Moreover, it shows unexpectedly high catalytic activities toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), with overpotentials of 310 mV for OER in alkaline solution and 60 mV for HER in acidic media at a current density of 10 mA cm−2, outperforming the benchmark RuO2 and comparable with Pt/C(20%), respectively. The enhanced multifunctional electrocatalytic properties are associated with the newly constructed active moiety Pt1O2Fe1N4, which protects Fe sites from harmful species. Density functional theory calculations reveal the synergy in the new active moiety, which promotes the proton adsorption and reduction kinetics. In addition, the grafted Pt1O2 dangling bonds may boost the OER activity. This study paves a new way to improve and extend NPMCs electrocatalytic properties through a precisely single‐atom to single‐atom grafting strategy.
An Efficient and Earth‐Abundant Oxygen‐Evolving Electrocatalyst Based on Amorphous Metal Borides
Authors: Nsanzimana Jean Marie Vianney , Peng Yuecheng , Xu Yang Yang , Thia Larissa , Wang Cheng , Xia Bao Yu , Wang Xin
Published: September 2017

Cost‐effective and efficient oxygen‐evolving electrocatalysts are urgently required for energy storage and conversion technologies. In this work, an amorphous trimetallic boride nanocatalyst (Fe–Co–2.3Ni–B) prepared by a simple approach is reported as a highly efficient oxygen evolution reaction electrocatalyst. It exhibits an overpotential (η) of 274 mV to deliver a geometric current density (jgeo) of 10 mA cm−2, a small Tafel slope of 38 mV dec−1, and excellent long‐term durability at a mass loading of 0.3 mg cm−2. The impressive electrocatalytic performance originates from the unique amorphous multimetal–metalloid complex nanostructure. From application's point of view, this work holds great promise as this process is simple and allows for large‐scale production of cheap, yet efficient, material.