bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing and enacting student governance and leadership training in higher education
Authors: Dollinger Mollie , Vanderlelie Jessica
Published: August 2019

Despite increased attention placed both in and outside Australia on student participation in university governance, there remains a gap in practices and programs that help support students to contribute across various governance groups, councils, and representative roles. This practice report explores two aspects of developing student partnership in governance at a research-intensive university in Australia. We will showcase a set of rationales co-created between students and staff on why partnership should be a critical aspect of higher education policy and governance. Secondly, we will provide an overview of a specialised training program that aims to provide students with foundational working knowledge of university governance practice, policies and language to bolster engagement within their roles. We will further discuss anticipated impacts and advance research and future practice in this area by highlighting key areas that require further exploration to further student engagement in governance structures.
The Deakin 'Students Helping Students' and 'Students as Partners' collection: A contemporary take on the classic cut
Authors: Milburn Lynn , Jones Dawn
Published: August 2019

Fashion metaphors are used to explore the relationship between Deakin’s ‘Students Helping Students’ strategy and its emerging ‘Students as Partners’ initiative. As the curtain is raised, the current ‘tertiary trend’ of Students as Partners is seen through a global lens. The Deakin Students Helping Students and Students as Partners collection is then paraded across the runway, at once unveiling savvy design and high-quality workmanship. A key feature of both Deakin’s Students Helping Students and Students as Partners models is that they are expressions of a community of practice approach and of social learning theory, with some variations in texture and palette. This ‘Absolutely Fabulous’ show concludes that while both looks are based on a timeless, ‘classic cut’ approach to education that engages both students and staff, each trend adds colour, interest and appeal. Fashions in education are sometimes fleeting, sometimes fun, and they are sure to invigorate, refresh and challenge.
Regional study hubs: Increasing student engagement to support regional students facing high first-year attrition risk factors
Authors: Davis Monica , Taylor Duncan
Published: August 2019

The Country Universities Centre (CUC) network of regional study hubs are an emerging tool for supporting regional students to achieve success in higher education. The CUC cohort of students, and regional students more generally, face several risk factors for first-year attrition including: external mode of study, over 25 years of age, part-time study load, alternative pathways to admission, and medium to low SES. In addition, work-life balance, financial considerations, and access to technology all create barriers to study for these students. The CUC facilities and staff provide academic, administrative and pastoral support to students, as well as creating a learning community to facilitate student-to-student interactions. The positive effect of the CUC support is shown by means of a survey and student case-studies.
Have Stock Markets Become Less Volatile After the Great Recession?
Authors: Aldeehani Talla M
Published: August 2019

This paper investigates volatility modeling in light of the 2008 global financial crisis. The study was motivated by the measures and regulations introduced by most of the countries following the shock to stabilize their financial markets. The theoretical proposition is that these measures should succeed in reducing volatility which would be modeled differently following the crisis. The adopted ARMA-GARCH process included positive and negative trading volume change to capture the asymmetric effect of trading volume on market volatility for seven international markets. The results indicate that the majority of these markets were not so successful in reducing volatility following the crisis. There is evidence of volatility persistence which dissipates very quickly. Although volatility is modeled differently before and after the crisis, each market is modeled uniquely. The effect of trading volume was found to be asymmetric. Only positive change was a valid predictor. Detailed discussions of the results, implications, and recommendations are provided.
Corporate Social Responsibility: Universities in the Kingdom of Bahrain
Authors: Tawash Afaf Ahmed , Al-Shirawi Abdulmonem M. , Sarea Adel M.
Published: August 2019

Corporate Social Responsibility (CSR) has become very vital for any corporation as many voices demand that entities must be accountable for business decisions and actions. Since universities are vital entities in the society as they provide higher education to the human factor, they have a huge role that compels them to adhere to CSR and to make it a part of their strategic planning. The study is about measuring the awareness of CSR in the management of universities in the Kingdom of Bahrain. The study used a descriptive survey method to analyze the relationship between Communication, CSR activities and Management’s transparency with the level of awareness of CSR. The respondents of the study are the top and middle level managers of universities where the primary tool in gathering data was a structured questionnaire. Secondary sources were utilized as well, such as: books, articles, unpublished thesis and other printed resources related to the study that were used to support and strengthen the findings of the study. The main finding is, there is a significant relationship between CSR activities and communication with awareness of CSR.
Social Studies Course from the Perspective of Parents -The Istanbul-Sultanbeyli Case
Authors: Baş Kenan , Durmuş Esen
Published: August 2019

The aim of this study is to identify the perspectives of parents on the "Social Studies" course. The case study design,one of the qualitative research methods, was used in accordance with the nature of the study. Data related to the studywere obtained through a semi-structured interview form prepared by the researchers. The data of the study wereobtained from the parents of students attending 5th, 6th and 7th grade of a state secondary school located in theIstanbul-Sultanbeyli district in the spring semester of 2017 and 2018 academic year. The data obtained were analyzedby content analysis. According to the data obtained from the research, the following results were obtained: Themajority of the parents apparently linked the concept of Social Studies to the concepts of History, Geography,Citizenship and Socialization. Parents thought that the subjects related to History, Geography, Citizenship Rights,Culture, Democracy, Human Rights and the life of Mustafa Kemal Atatürk were taught in the Social Studies course.Nevertheless, it was seen that the parents wished to see the concepts such as Love of Motherland, Nation, Communityand National Flag, Etiquette, Cultural Values, Freedom, Democracy, Equality to be taught in the Social Studies courses.While the parents mostly compared the Social Studies courses with such organs as the Brain, Kidney, Heart, Eye,Stomach and Intestine, they considered it as appropriate to place this course in the last places in terms of importance. Inaddition, it was found that majority of the parents did not want their children to become social studies teachers in thefuture.
The Interest in Islamic Finance Contracts in Saudi Arabia as Viewed by Google Trends
Authors: Aldarabseh Wesal M.
Published: August 2019

Several Islamic contracts have been used by Islamic banks to cover the financial needs of their customers. The contracts include Murabahah, Ijarah, Tawarruq, Mudarabah, Musharakah, Salam, and Istisna'. In the current study, the interest in Islamic financial contracts in the past 5 years (2014-2019) in Saudi Arabia as viewed by Google trends was examined. The interest in Murabahah showed increases with the years, whereas decreases in the interest of Tawarruq, Salam Mudarabah were observed in the last years. However, the interest in Ijarah and Istisna' was stable during the examined period. With respect to Musharakah, the interest decreased with years until 2017 then it showed slight increases in 2018 and 2019. Differences in the interest of financial contracts were also observed across different regions of Saudi Arabia. The interest in Ijarah, Tawarruq and Istisna’ was higher in Riyadh, whereas the interest in Murabahah and Musharakah was higher in Ha’il than other Saudi regions The present findings can be used by Islamic banks to shape their financing services according to observed interest trends and across different regions of Saudi Arabia.
Does Stock Market Performance Affect Economic Growth? Empirical Evidence from Saudi Arabia
Authors: Al Rasasi Moayad H. , Alsabban Soleman O. , Alarfaj Omar A.
Published: August 2019

This research paper investigates the impact of stock prices on real economic activity in the Saudi Arabian economy. We utilize various econometric techniques – Johansen and Juselius’s (1990) cointegration tests and Granger’s (1969) causality test – to assess such a relationship, based on quarterly observations spanning the period from the first quarter of 2010 to the fourth quarter of 2018. Our empirical evidence indicates the presence of a significant cointegrating relationship between the two variables being examined; in other words, stock prices have a significant impact on real economic growth. Specifically, the estimated long-run relationship reveals that a 1 percent increase in stock prices would boost economic growth by 0.32 percent. In addition, the error correction model suggests that when the economy deviates from its steady state condition, it needs about a year and a half to return to its equilibrium condition. Lastly, this paper applies the most common Granger causality test, which confirms the essential role of stock prices in predicting changes in economic growth.
A guide to applying the Good Publication Practice 3 Guidelines in the Asia-Pacific region
Authors: Hesp Blair , Arai Katshisa , Chu Magdalene , Chuah Stefanie , Curameng Jose Miguel , Kamat Sandeep , Ma Zhigang , Sakko Andrew , Fernandez Hazel
Published: August 2019

Numerous recommendations and guidelines aim to improve the quality, timeliness and transparency of medical publications. However, these guidelines use ambiguous language that can be challenging to interpret, particularly for speakers of English as a second language. Cultural expectations within the Asia-Pacific region raise additional challenges. Several studies have suggested that awareness and application of ethical publication practices in the Asia-Pacific region is relatively low compared with other regions. However, guidance on applying ethical publication practice guidelines in the Asia-Pacific region is lacking. This review aims to improve publication practices in the Asia-Pacific region by providing guidance on applying the 10 principles of the Good Publication Practice 3 (GPP3) guidelines and the International Committee of Medical Journal Editors (ICMJE) criteria for authorship. Recommendations are provided for encore presentations, applying the ICMJE authorship criteria in the context of regional cultural expectations, and the role of study sponsors and professional medical writers. Ongoing barriers to compliance with guidelines are also highlighted, and additional guidance is provided to support authors submitting manuscripts for publication. The roles of regional journals, regulatory authorities and professional bodies in improving practices are also discussed.
Coupling adaptive molecular evolution to phylodynamics using fitness-dependent birth-death models
Authors: Rasmussen David A , Stadler Tanja
Published: August 2019

Beneficial and deleterious mutations cause the fitness of lineages to vary across a phylogeny and thereby shape its branching structure. While standard phylogenetic models do not allow mutations to feedback and shape trees, birth-death models can account for this feedback by letting the fitness of lineages depend on their type. To date, these multi-type birth-death models have only been applied to cases where a lineage’s fitness is determined by a single character state. We extend these models to track sequence evolution at multiple sites. This approach remains computationally tractable by tracking the genotype and fitness of lineages probabilistically in an approximate manner. Although approximate, we show that we can accurately estimate the fitness of lineages and site-specific mutational fitness effects from phylogenies. We apply this approach to estimate the population-level fitness effects of mutations in Ebola and influenza virus, and compare our estimates with in vitro fitness measurements for these mutations.
Variation in denitrifying bacterial communities along a primary succession in the Hailuogou Glacier retreat area, China
Authors: Bai Yan , Huang Xiying , Zhou Xiangrui , Xiang Quanju , Zhao Ke , Yu Xiumei , Chen Qiang , Jiang Hao , Nyima Tashi , Gao Xue , Gu Yunfu
Published: August 2019

Background

The Hailuogou Glacier is located at the Gongga Mountain on the southeastern edge of the Tibetan Plateau, and has retreated continuously as a result of global warming. The retreat of the Hailuogou Glacier has left behind a primary succession along soil chronosequences. Hailuogou Glacier’s retreated area provides an excellent living environment for the colonization of microbes and plants, making it an ideal model to explore plant successions, microbial communities, and the interaction of plants and microbes during the colonization process. However, to date, the density of the nitrogen cycling microbial communities remain unknown, especially for denitrifiers in the primary succession of the Hailuogou Glacier. Therefore, we investigated the structural succession and its driving factors for denitrifying bacterial communities during the four successional stages (0, 20, 40, and 60 years).

Methods

The diversity, community composition, and abundance of nosZ-denitrifiers were determined using molecular tools, including terminal restriction fragment length polymorphism and quantitative polymerase chain reactions (qPCR).

Results

nosZ-denitrifiers were more abundant and diverse in soils from successional years 20–60 compared to 0–5 years, and was highest in Site3 (40 years). The denitrifying bacterial community composition was more complex in older soils (40–60 years) than in younger soils (≤20 years). The terminal restriction fragments (T-RFs) of Azospirillum (90 bp) and Rubrivivax (95 bp) were dominant in soisl during early successional stages (0–20 years) and in the mature phase (40–60 years), respectively. Specific T-RFs of Bradyrhizobium (100 bp) and Pseudomonas (275 bp) were detected only in Site3 and Site4, respectively. Moreover, the unidentified 175 bp T-RFs was detected only in Site3. Of the abiotic factors that were measured in this study, soil available phosphorus, available potassium and denitrifying enzyme activity (DEA) correlated significantly with the community composition of nosZ-denitrifiers (P < 0.05 by Monte Carlo permutation test within RDA analysis).
Factors associated with the composition and diversity of the cervical microbiota of reproductive-age Black South African women: a retrospective cross-sectional study
Authors: Onywera Harris , Williamson Anna-Lise , Mbulawa Zizipho Z.A. , Coetzee David , Meiring Tracy L.
Published: August 2019

Background

Lactobacillusspp. are common bacteria in the cervical and vaginal microbiota (CVM) and are thought to represent a “healthy” cervicovaginal state. Several studies have found an independent association between ethnicity/race and cervical and vaginal microbiota (CVM) composition. Women of sub-Saharan African descent appear to be significantly more likely to have non-Lactobacillus-dominated CVM compared to women of European descent. The factors contributing to these differences remain to be fully elucidated. The CVM of Black South African women and factors influencing their CVM remain understudied. In this study, we characterized the cervical microbiota of reproductive-age South African women and assessed the associations of these microbiota with participants’ metadata.

Methods

The cervical microbiota from cervical DNA of 62 reproductive-age women were profiled by Ion Torrent sequencing the V4 hypervariable region of the bacterial 16S ribosomal RNA (rRNA) gene and analyzed with the Quantitative Insights Into Microbial Ecology (QIIME), UPARSE, and metagenomeSeq tools. Associations between cervical microbiota and participants’ metadata were assessed using GraphPad Prism, R packages and an in-house script.

Results

The cervical microbiota clustered into three distinct community state types (CSTs):Lactobacillus iners-dominated cervical microbiota (CST I (38.7%, 24/62)), unclassifiedLactobacillus-dominated cervical microbiota (CST II (4.8%, 3/62)), and diverse cervical microbiota (CST III (56.5%, 35/62)) with an array of heterogeneous bacteria, predominantly the bacterial vaginosis (BV)-associatedGardnerella,Prevotella,Sneathia, andShuttleworthia. CST III was associated with BV (p = 0.001). Women in CST I were more likely to be on hormonal contraception, especially progestin-based, compared to women in CST III (odds ratio: 5.2 (95% CI [1.6–17.2]);p = 0.005). Women on hormonal contraception had a significantly lower alpha (Shannon indices: 0.9 (0.2–1.9) versus 2.3 (0.6–2.3);p = 0.025) and beta (permutational multivariate analysis of variance (PERMANOVA) pseudo-F statistic =4.31,p = 0.019) diversity compared to non-users. There was no significant difference in the alpha (Shannon indices: 1.0 (0.3–2.2) versus 1.9 (0.3–2.2);p = 0.483) and beta (PERMANOVA pseudo-Fstatistic = 0.89,p = 0.373) diversity in women with versus without human papillomavirus infection.

Conclusions

The majority of Black women in our study had non-Lactobacillus-dominated cervical microbiota. Additional studies are needed to examine whether such microbiota represent abnormal, intermediate or variant states of health. Lastly, the association of hormonal contraception withL. inersdominance requires further in-depth research to confirm this association, determine its biological mechanism and whether it has a beneficial effect on the cervicovaginal health.
Atom‐by‐Atom Fabrication of Single and Few Dopant Quantum Devices
Authors: Wyrick Jonathan , Wang Xiqiao , Kashid Ranjit V. , Namboodiri Pradeep , Schmucker Scott W. , Hagmann Joseph A. , Liu Keyi , Stewart Michael D. , Richter Curt A. , Bryant Garnett W. , Silver Richard M.
Published: August 2019

Atomically precise fabrication has an important role to play in developing atom‐based electronic devices for use in quantum information processing, quantum materials research, and quantum sensing. Atom‐by‐atom fabrication has the potential to enable precise control over tunnel coupling, exchange coupling, on‐site charging energies, and other key properties of basic devices needed for solid‐state quantum computing and analog quantum simulation. Using hydrogen‐based scanning probe lithography, individual dopant atoms are deterministically placed relative to atomically aligned contacts and gates to build single electron transistors, single atom transistors, and gate‐controlled quantum sensing devices. The key steps required to fabricate and demonstrate the essential building blocks needed for spin selective initialization/readout and coherent quantum manipulation are described.
Irradiation of Transition Metal Dichalcogenides Using a Focused Ion Beam: Controlled Single‐Atom Defect Creation
Authors: Thiruraman Jothi Priyanka , Masih Das Paul , Drndić Marija
Published: August 2019

Manipulation and structural modifications of 2D materials for nanoelectronic and nanofluidic applications remain obstacles to their industrial‐scale implementation. Here, it is demonstrated that a 30 kV focused ion beam can be utilized to engineer defects and tailor the atomic, optoelectronic, and structural properties of monolayer transition metal dichalcogenides (TMDs). Aberration‐corrected scanning transmission electron microscopy is used to reveal the presence of defects with sizes from the single atom to 50 nm in molybdenum (MoS2) and tungsten disulfide (WS2) caused by irradiation doses from 1013 to 1016 ions cm−2. Irradiated regions across millimeter‐length scales of multiple devices are sampled and analyzed at the atomic scale in order to obtain a quantitative picture of defect sizes and densities. Precise dose value calculations are also presented, which accurately capture the spatial distribution of defects in irradiated 2D materials. Changes in phononic and optoelectronic material properties are probed via Raman and photoluminescence spectroscopy. The dependence of defect properties on sample parameters such as underlying substrate and TMD material is also investigated. The results shown here lend the way to the fabrication and processing of TMD nanodevices.
Brewster Mode‐Enhanced Sensing with Hyperbolic Metamaterial
Authors: Sreekanth Kandammathe Valiyaveedu , Mahalakshmi Perumal , Han Song , Mani Rajan Murugan Senthil , Choudhury Pankaj Kumar , Singh Ranjan
Published: August 2019

Hyperbolic metamaterials (HMMs) are used to demonstrate extreme sensitivity biosensing by exciting their high‐k modes. However, momentum couplers, such as subwavelength diffraction grating or bulky high‐index prism, are required to excite these nonradiative modes, which is not cost‐effective and thus not suitable for point‐of‐care applications. Here, a cost‐effective and scalable HMM‐based sensor platform is proposed and experimentally demonstrated, by exciting the Brewster mode of HMM from free‐space. The excitation of Brewster modes is shown in a multilayered HMM comprising of alternating thin layers of TiN and phase change material, such as Sb2S3. Brewster modes in the hyperbolic region occur due to abrupt phase change, and enhanced Goos–Hänchen shift is realized at the Brewster angle. The enhanced refractive index sensing is demonstrated by exploiting the singular phase of light associated with the Brewster mode of the proposed HMM. This microfluidics integrated lithography‐free nanophotonic device can be a potential sensor platform for a cost‐effective development of label‐free biosensors for point‐of‐care applications.
Quantifying Performance of Permeation Barrier—Encapsulation Systems for Flexible and Glass‐Based Electronics and Their Application to Perovskite Solar Cells
Authors: Castro‐Hermosa Sergio , Top Michiel , Dagar Janardan , Fahlteich John , Brown Thomas M.
Published: August 2019

Effective transparent barrier/encapsulation systems represent a key enabling technology for large‐area electronics. Securing stability to the environment is vital. Here, the effects of architectures, application processes, and water vapor transmission rates (WVTR) of transparent flexible ultra‐high permeation barrier films (UHPBF) applied to substrates with adhesive resins are unraveled for attaining long lifetime, and compared with polyethylene terephthalate and glass barriers. How strongly performance of barrier/adhesive systems depends on barrier orientation, adhesion, manipulation, defects, and storage procedures is quantified via calcium tests. Furthermore, it is found that introducing an additional adhesion‐promoting layer on the standard UHPBF stack reduces WVTRs by a factor of 5 compared to barriers without it. Finally, barriers are used for sealing and encapsulation of perovskite solar cells (PSCs) enabling the extraction of a relationship between WVTRs of barrier/adhesive systems and degradation rates (DR) of PSCs. DR fall exponentially when WVTRs decrease from 101 to 10−3 g m−2 d−1. Outside that range any gains or losses are mitigated by tailing of the sigmoid curve relating the two parameters. Results highlight important factors which will help those developing strategies relating to encapsulation, barrier, adhesive and sealant systems and stable optoelectronic devices on glass and flexible substrates.
Transparent Magnetoelectric Materials for Advanced Invisible Electronic Applications
Authors: Polícia Rita , Lima Ana Catarina , Pereira Nélson , Calle Esther , Vázquez Manuel , Lanceros‐Mendez Senentxu , Martins Pedro
Published: August 2019

The need for flexible and transparent smart materials is leading to substantial advances in principles, material combinations, and technologies. Particularly, the development of optically transparent magnetoelectric (ME) materials will open the range of applications to new directions such as transparent sensors, touch display panels, multifunctional flat panel displays, and optical magnetic coatings. In this work, a flexible and transparent ME composite is made of magnetostrictive Fe72.5Si12.5B15 microwires and piezoelectric poly(vinylidene fluoride‐trifluoroethylene). The high magnetostriction of Fe72.5Si12.5B15 (35 ppm) enables superior ME voltage response (65 mV cm−1 Oe−1) obtained at the critical longitudinal magnetic field equating the transverse anisotropy (14500 A m−1) on the external shell of the microwire.
A New View of Supercapacitors: Integrated Supercapacitors
Authors: Zhu Qiancheng , Zhao Danyang , Cheng Mingyu , Zhou Jianqing , Owusu Kwadwo Asare , Mai Liqiang , Yu Ying
Published: August 2019

Charging times ranging from seconds to minutes with high power densities can be achieved by electrochemical capacitors in principle. Over the past few decades, the performance of supercapacitors has been greatly improved by the utilization of new materials, preparation of unique nanostructures, investigation of electrolytes, and so on. However, the discovery of the related basic theory is very limited. Herein, a new view of a supercapacitor called the “integrated supercapacitor” is proposed. The electrode of the integrated supercapacitor consists of certain positive and negative materials. With this design, a single integrated electrode can work in both the positive and negative potential windows simultaneously. Additionally, the integrated full supercapacitor device shows a much higher capacitance and wider potential window than traditional single symmetric and asymmetric supercapacitors, which results from its multiple mechanisms, including the traditional positive//positive symmetric, positive//negative asymmetric, and negative//negative symmetric full supercapacitor mechanisms.
In Operando Visualization of the Electrochemical Formation of Liquid Polybromide Microdroplets
Authors: Wu Yutong , Huang Po‐Wei , Howe Joshua D. , Yan Yu , Martinez Jose , Marianchuk Anna , Zhang Yamin , Chen Hang , Liu Nian
Published: August 2019

Zinc–bromine flow batteries are promising for stationary energy storage, and bromine‐complexing agents have been used to form phase‐separated liquid polybromide products. However, an understanding of the dynamics of polybromide nucleation is limited due to the beam sensitivity and complexity of polybromides. Here we report an in operando platform composed of dark‐field light microscopy and a transparent electrochemical cell to reveal the dynamics of polybromide formation in their native environment. Using our platform, we confirm and reveal the liquid nature, chemical composition, pinning effect (strong interaction with Pt), residual effect (residual charge products on the surface), self‐discharging, and over‐oxidation of the polybromide products. The results provide insights into the role of complexing agents and guide the future design of zinc–bromine flow batteries. Furthermore, our in operando platform can potentially be used to study sensitive species and phases in other electrochemical reactions.
Konformativer Umbau von Porphyrinen als Rezeptoren mit schaltbaren N‐H⋅⋅⋅X‐Bindungsmodi
Authors: Norvaiša Karolis , Flanagan Keith J. , Gibbons Dáire , Senge Mathias O.
Published: August 2019

Die Selektivität und funktionale Variabilität von Porphyrinkofaktoren basiert typischerweise auf der Substratbindung durch Metalloporphyrine, wobei die Pyrrolstickstoffatome nur zur Chelatisierung der Metallionen dienen. In einem ersten Schritt zu Porphyrinzentren mit “enzymähnlicher” Aktivität zeigt eine strukturelle und spektroskopische Untersuchung der Substratbindung im Kern jedoch, dass ein sattelverbogenes Porphyrin mit peripheren Aminorezeptorgruppen (1, 2,3,7,8,12,13,17,18‐Oktaethyl‐5,10,15,20‐tetrakis(2‐aminophenyl)porphyrin), abhängig von der Azidität der Lösung, Analyte in einer schaltbaren Weise koordiniert. Das supramolekulare Ensemble weist eine hohe Affinität und Selektivität für das Pyrophosphatanion (2.26±0.021)×109 m−1 auf. 1H‐NMR‐Spektroskopie liefert Einblicke in den wahrscheinlichen Bindungsmodus und erlaubt die Charakterisierung der Atropisomere, deren Struktur auch durch Röntgenstrukturanalysen aufgeklärt wurde.
DNA Origami Nanoplate‐Based Emulsion with Nanopore Function
Authors: Ishikawa Daisuke , Suzuki Yuki , Kurokawa Chikako , Ohara Masayuki , Tsuchiya Misato , Morita Masamune , Yanagisawa Miho , Endo Masayuki , Kawano Ryuji , Takinoue Masahiro
Published: August 2019

Bio‐inspired functional microcapsules have attracted increasing attention in many fields from physical/chemical science to artificial‐cell engineering. Although particle‐stabilised microcapsules are advantageous for their stability and functionalisation potential, versatile methods for their functionalisation are desired to expand their possibilities. This study reports a water‐in‐oil microdroplet stabilised with amphiphilic DNA origami nanoplates. By utilising DNA nanotechnology, DNA nanoplates were designed as a nanopore device for ion transportation and to stabilise the oil–water interface. Microscopic examination revealed the microcapsule formed by the accumulation of amphiphilic DNA nanoplates at the oil–water interface. Ion current measurements revealed the nanoplate pores functioned as channel to transport ions. These findings provide a general strategy for the programmable design of microcapsules to engineer artificial cells and molecular robots.
A Nanoemulsion with A Porphyrin Shell for Cancer Theranostics
Authors: Hou Wenxiu , Lou Jenny W. H. , Bu Jiachuan , Chang Enling , Ding Lili , Valic Michael , Jeon Han Ho , Charron Danielle M. , Coolens Catherine , Cui Daxiang , Chen Juan , Zheng Gang
Published: August 2019

A nanoemulsion with a porphyrin shell (NewPS) was created by the self‐assembly of porphyrin salt around an oil core. The NewPS system has excellent colloidal stability, is amenable to different porphyrin salts and oils, and is capable of co‐loading with chemotherapeutics. The porphyrin salt shell enables porphyrin‐dependent optical tunability. The NewPS consisting of pyropheophorbide a mono‐salt has a porphyrin shell of ordered J‐aggregates, which produced a narrow, red‐shifted Q‐band with increased absorbance. Upon nanostructure dissociation, the fluorescence and photodynamic reactivity of the porphyrin monomers are restored. The spectrally distinct photoacoustic imaging (at 715 nm by intact NewPS) and fluorescence increase (at 671 nm by disrupted NewPS) allow the monitoring of NewPS accumulation and disruption in mice bearing KB tumors to guide effective photodynamic therapy. Substituting the oil core with Lipiodol affords additional CT contrast, whereas loading paclitaxel into NewPS facilitates drug delivery.
Enabling Superior Electrochemical Properties for Highly Efficient Potassium Storage by Impregnating Ultrafine Sb Nanocrystals within Nanochannel‐Containing Carbon Nanofibers
Authors: Ge Xufang , Liu Shuhu , Qiao Man , Du Yichen , Li Yafei , Bao Jianchun , Zhou Xiaosi
Published: August 2019

Sb‐based nanocomposites are attractive anode materials for batteries as they exhibit large theoretical capacity and impressive working voltage. However, tardy potassium ion diffusion characteristics, unstable Sb/electrolyte interphase, and huge volume variation pose a challenge, hindering their practical use for potassium‐ion batteries (PIBs). Now, a simple robust strategy is presented for uniformly impregnating ultrasmall Sb nanocrystals within carbon nanofibers containing an array of hollow nanochannels (denoted u‐Sb@CNFs), resolving the issues above and yielding high‐performance PIBs. u‐Sb@CNFs can be directly employed as an anode, thereby dispensing with the need for conductive additives and binders. Such a judiciously crafted u‐Sb@CNF‐based anode renders a set of intriguing electrochemical properties, representing large charge capacity, unprecedented cycling stability, and outstanding rate performance. A reversible capacity of 225 mAh g−1 is retained after 2000 cycles at 1 A g−1.
A Fluorescent Kinase Inhibitor that Exhibits Diagnostic Changes in Emission upon Binding
Authors: Fleming Cassandra L. , Sandoz Patrick A. , Inghardt Tord , Önfelt Björn , Grøtli Morten , Andréasson Joakim
Published: August 2019

The development of a fluorescent LCK inhibitor that exhibits favourable solvatochromic properties upon binding the kinase is described. Fluorescent properties were realised through the inclusion of a prodan‐derived fluorophore into the pharmacophore of an ATP‐competitive kinase inhibitor. Fluorescence titration experiments demonstrate the solvatochromic properties of the inhibitor, in which dramatic increase in emission intensity and hypsochromic shift in emission maxima are clearly observed upon binding LCK. Microscopy experiments in cellular contexts together with flow cytometry show that the fluorescence intensity of the inhibitor correlates with the LCK concentration. Furthermore, multiphoton microscopy experiments demonstrate both the rapid cellular uptake of the inhibitor and that the two‐photon cross section of the inhibitor is amenable for excitation at 700 nm.
Synthesis and Utility of Neptunium(III) Hydrocarbyl Complex
Authors: Myers Alexander J. , Tarlton Michael L. , Kelley Steven P. , Lukens Wayne W. , Walensky Justin R.
Published: August 2019

To extend organoactinide chemistry beyond uranium, reported here is the first structurally characterized transuranic hydrocarbyl complex, Np[η4‐Me2NC(H)C6H5]3 (1), from reaction of NpCl4(DME)2 with four equivalents of K[Me2NC(H)C6H5]. Unlike the UIII species, the neptunium analogue can be used to access other NpIII complexes. The reaction of 1 with three equivalents of HE2C(2,6‐Mes2‐C6H3) (E=O, S) yields [(2,6‐Mes2‐C6H3)CE2]3Np(THF)2, maintaining the trivalent oxidation state.
Crystal structure of a NIR‐Emitting DNA‐Stabilized Ag16 Nanocluster
Authors: Cerretani Cecilia , Kanazawa Hiroki , Vosch Tom , Kondo Jiro
Published: August 2019

DNA has been used as a scaffold to stabilize small, atomically monodisperse silver nanoclusters, which have attracted attention due to their intriguing photophysical properties. Herein, we describe the X‐ray crystal structure of a DNA‐encapsulated, near‐infrared emitting Ag16 nanocluster (DNA–Ag16NC). The asymmetric unit of the crystal contains two DNA–Ag16NCs and the crystal packing between the DNA–Ag16NCs is promoted by several interactions, such as two silver‐mediated base pairs between 3′‐terminal adenines, two phosphate–Ca2+–phosphate interactions, and π‐stacking between two neighboring thymines. Each Ag16NC is confined by two DNA decamers that take on a horse‐shoe‐like conformation and is almost fully shielded from the solvent environment. This structural insight will aid in the determination of the structure/photophysical property relationship for this class of emitters and opens up new research opportunities in fluorescence imaging and sensing using noble‐metal clusters.
Spectroscopic Characterization of an Eight‐Iron Nitrogenase Cofactor Precursor that Lacks the “9th Sulfur”
Authors: Jasniewski Andrew J. , Wilcoxen Jarett , Tanifuji Kazuki , Hedman Britt , Hodgson Keith O. , Britt R. David , Hu Yilin , Ribbe Markus W.
Published: August 2019

Nitrogenases catalyze the reduction of N2 to NH4+ at its cofactor site. Designated the M‐cluster, this [MoFe7S9C(R‐homocitrate)] cofactor is synthesized via the transformation of a [Fe4S4] cluster pair into an [Fe8S9C] precursor (designated the L‐cluster) prior to insertion of Mo and homocitrate. We report the characterization of an eight‐iron cofactor precursor (designated the L*‐cluster), which is proposed to have the composition [Fe8S8C] and lack the “9th sulfur” in the belt region of the L‐cluster. Our X‐ray absorption and electron spin echo envelope modulation (ESEEM) analyses strongly suggest that the L*‐cluster represents a structural homologue to the l‐cluster except for the missing belt sulfur. The absence of a belt sulfur from the L*‐cluster may prove beneficial for labeling the catalytically important belt region, which could in turn facilitate investigations into the reaction mechanism of nitrogenases.
Molecular Design Strategy for Ordered Mesoporous Stoichiometric Metal Oxide
Authors: Wang Changyao , Wan Xiaoyue , Duan Linlin , Zeng Peiyuan , Liu Liangliang , Guo Dingyi , Xia Yuan , Elzatahry Ahmed A. , Xia Yongyao , Li Wei , Zhao Dongyuan
Published: August 2019

A molecular design strategy is used to construct ordered mesoporous Ti3+‐doped Li4Ti5O12 nanocrystal frameworks (OM‐Ti3+‐Li4Ti5O12) by the stoichiometric cationic coordination assembly process. Ti4+/Li+‐citrate chelate is designed as a new molecular precursor, in which the citrate can not only stoichiometrically coordinate Ti4+ with Li+ homogeneously at the atomic scale, but also interact strongly with the PEO segments in the Pluronic F127. These features make the co‐assembly and crystallization process more controllable, thus benefiting for the formation of the ordered mesostructures. The resultant OM‐Ti3+‐Li4Ti5O12 shows excellent rate (143 mAh g−1 at 30 C) and cycling performances (<0.005 % fading per cycle). This work could open a facile avenue to constructing stoichiometric ordered mesoporous oxides or minerals with highly crystalline frameworks.
Conformational Re‐engineering of Porphyrins as Receptors with Switchable N−H⋅⋅⋅X‐Type Binding Modes
Authors: Norvaiša Karolis , Flanagan Keith J. , Gibbons Dáire , Senge Mathias O.
Published: August 2019

The selectivity and functional variability of porphyrin cofactors are typically based on substrate binding of metalloporphyrins wherein the pyrrole nitrogen units only serve to chelate the metal ions. Yet, using the porphyrin inner core system for other functions is possible through conformational engineering. As a first step towards porphyrin “enzyme‐like” active centers, a structural and spectroscopic study of substrate binding to the inner core porphyrin system shows that a highly saddle‐distorted porphyrin with peripheral amino receptor groups (1, 2,3,7,8,12,13,17,18‐octaethyl‐5,10,15,20‐tetrakis(2‐aminophenyl)porphyrin) coordinates analytes in a switchable manner dependent on the acidity of the solution. The supramolecular ensemble exhibits exceptionally high affinity to and selectivity for the pyrophosphate anion (2.26±0.021)×109 m−1. 1H NMR spectroscopic studies provided insight into the likely mode of binding and the characterization of atropisomers, all four of which were also studied by X‐ray crystallography.
A Metallaphotoredox Strategy for the Cross‐Electrophile Coupling of α‐Chloro Carbonyls with Aryl Halides
Authors: Chen Tiffany Q. , MacMillan David W. C.
Published: August 2019

Here, we demonstrate that a metallaphotoredox‐catalyzed cross‐electrophile coupling mechanism provides a unified method for the α‐arylation of diverse activated alkyl chlorides, including α‐chloroketones, α‐chloroesters, α‐chloroamides, α‐chlorocarboxylic acids, and benzylic chlorides. This strategy, which is effective for a wide variety of aryl bromide coupling partners, is predicated upon a halogen atom abstraction/nickel radical‐capture mechanism that is generically successful across an extensive range of carbonyl substrates. The construction and use of arylacetic acid products have further enabled two‐step protocols for the delivery of valuable building blocks for medicinal chemistry, such as aryldifluoromethyl and diarylmethane motifs.
Building a Bridge from Papermaking to Solar Fuels
Authors: Jiang Zaiyong , Zhang Xinhan , Sun Wei , Yang Deren , Duchesne Paul N. , Gao Yugang , Wang Zeyan , Yan Tingjiang , Yuan Zhimin , Yang Guihua , Ji Xingxiang , Chen Jiachuan , Huang Baibiao , Ozin Geoffrey A.
Published: August 2019

Black liquor, an industrial waste product of papermaking, is primarily used as a low‐grade combustible energy source. Despite its high lignin content, the potential utility of black liquor as a feedstock in products manufacturing, remains to be exploited. Demonstrated here in is the use of black liquor as a primary feed‐stock for synthesizing graphene quantum dots that exhibit both up‐conversion and photoluminescence when excited using visible/near‐infrared radiation, thereby enabling the photosensitization of ultraviolet‐absorbing TiO2 nanosheets. In addition, these graphene quantum dots can trap photo‐generated electrons to realize the effective separation of electron‐hole pairs. Together, these two processes facilitate the solar‐powered generation of H2 from H2O, and CO from H2O–CO2, using broadband solar radiation.
Withdrawal: Quantitative Synthesis of Temperature‐responsive Polymersomes by Multiblock Polymerization
Authors: Liu Xiaoling , Zhou Dongxu , Feng Yunbo , Gou Jing , Li Chenxi , He Chao , Zhao Weifeng , Sun Shudong , Zhao Changsheng , Appelhans Dietmar , Voit Brigitte
Published: August 2019

This Communication, published online on 14 August 2019 in Wiley Online Library (onlinelibrary.wiley.com), has been withdrawn by agreement between the corresponding authors, the journal's Executive Committee, and Wiley‐VCH GmbH, Weinheim. The withdrawal has been agreed upon following the explanation by the authors that problems with a microscopy image presented in Figure 4 of the article cannot be fully clarified.
Network latency and long‐distance robotic telestenting: Exploring the potential impact of network delays on telestenting performance
Authors: Madder Ryan D. , VanOosterhout Stacie , Mulder Abbey , Bush Jared , Martin Samuel , Rash Adam J. , Tan Jose Mariano , Parker Jessica L. , Kalafut Andrew , Li Yao , Kottenstette Nicholas , Bergman Per , Nowak Brent
Published: August 2019

Objective

This study evaluated the impact of network latency on telestenting performance.

Background

The feasibility of long‐distance robotic telestenting was recently demonstrated, yet the impact of network performance on telestenting remains unknown.

Methods

Ex vivo and in vivo telestenting models were constructed by connecting a robotic drive over a wired network to a robotic control system up to 103 miles away. During consecutive attempts to robotically wire a coronary artery, investigators randomly added signal latencies from 0 to 1,000 ms. Outcomes included wiring success, wiring time (time to advance wire to preselected target landmark), and perceived latency score (5 = imperceptible; 4 = noticeable but minor; 3 = noticeable; 2 = noticeable and major; 1 = unacceptable).

Results

Wiring success was achieved in 95 of 95 attempts in the ex vivo model and in 57 of 57 attempts in vivo. No significant difference in wiring time was observed across added latencies from 0 to 1,000 ms in the ex vivo (p = .64) or in vivo (p = .40) models. Compared to an added latency of 0 ms, perceived latency scores were not significantly different for added latencies of 150 and 250 ms (p = NS for both), but were significantly lower for latencies ≥400 ms (p < .001).

Conclusions

Added latencies up to 250 ms were not associated with perceived latency, but latencies ≥400 ms were perceptible. Based on these findings, future telestenting studies should utilize networks with latencies ≤250 ms if perceived latency is to be avoided.
Carotid artery stenting is safe and effective for symptomatic patients with acute coronary syndrome
Authors: Casana Renato , Tolva Valerio Stefano , Odero Andrea , Malloggi Chiara , Silani Vincenzo , Parati Gianfranco
Published: August 2019

Background

Patients with symptomatic carotid stenosis recently treated with percutaneous transluminal coronary angioplasty (PTCA) for acute coronary syndrome (ACS) are always classified as at high risk for surgery, given that they are required uninterrupted dual antiplatelet therapy. In this regard, carotid artery stenting (CAS) may represent a valid alternative.

Objective

The purpose of this study is to overview CAS outcomes in symptomatic patients with and without ACS.

Methods

One hundred fifty‐one consecutive symptomatic patients who underwent CAS between 2010 and 2017 in a single institution were included in this study, of which 66 (43.7%) were identified as having ACS. All patients were followed‐up with carotid duplex ultrasound scan and a neurological assessment of symptoms status at 30‐day postprocedure and at 3, 6, and 12 months, with annual follow‐up after that for 3 years.

Results

Among symptomatic ACS patients, common risks factors were active smoking, metabolic syndrome, diabetes, and hypertension. In the short‐term follow‐up, no significant differences were observed among rates of death, stroke, myocardial infarction (MI), and restenosis, between patients with and without ACS. Mean clinical follow‐up was 28.2 (12.3) months. In the long‐term follow‐up, higher rates of death and MI were recorded in patients with ACS (death: 11.4% vs. 5.4%, p = .04; MI: 11.4% vs. 3.6%, p = .02), owing to the complexity of these patients.

Conclusions

This single‐center study suggested that CAS is a safe and effective treatment for patients with symptomatic carotid artery stenosis, who recently underwent PTCA for ACS, requiring uninterrupted dual antiplatelet therapy.
Catalysts Supported by Homochiral Molecular Helices: A New Concept to Implement Asymmetric Amplification in Catalytic Science
Authors: Li Yan , Bouteiller Laurent , Raynal Matthieu
Published: August 2019

Connecting intrinsically achiral catalytic centers to helical polymers provides a new class of asymmetric catalysts whose selectivity exclusively stems from the chiral environment provided by the helical polymer. Chirality amplification phenomena allow to control the handedness and the helical sense excess of these polymers which in turn dictate the stereochemical direction and the extent of enantioinduction, respectively, obtained in the course of the asymmetric reaction. This minireview is focused on such helical catalysts built either on a covalent or a non‐covalent scaffold and for which the handedness is controlled by an asymmetric polymerization reaction, by enantiopure monomers or by chiral additives. The selectivity of catalysts based on a dynamic helical backbone can be tuned by changing the solvent or with additives. The fact that the enantiomeric state of such asymmetric catalysts can be switched in a predictable way is particularly emphasized.
Electrons and Holes as Catalysts in Organic Electrosynthesis
Authors: Francke Robert , Little R. Daniel
Published: August 2019

Invited for this month's cover picture is Robert Francke from the University of Rostock (Germany) and R. Daniel Little from the University of California Santa Barbara (USA). The cover picture highlights the catalytic effect of heterogeneous electron transfers on chemical reactions of organic molecules (“electrochemical catalysis”). A comparison is shown between the typical energy profile of a thermally induced reaction and the corresponding electrochemically catalyzed transformation using the example of the Newman‐Kwart rearrangement. Read the full text of the Minireview at 10.1002/celc.201900432.
Bis‐4,4′‐biphenyl Ring Embedded Octaphyrin with Three Distinct Conformational Structures
Authors: Chitranshi Sangya , Adinarayana B. , Das Mainak , Cha Won‐Young , Kim Dongho , Srinivasan A.
Published: August 2019

Three distinct conformational structures of carbaoctaphyrins were prepared by incorporating bis‐4,4'‐biphenyl units in the macrocyclic core. The free‐base form adopts a figure‐eight conformation, whereas the protonation triggers a conformational change with a pyrrole ring inversion and acquires an open‐framework structure. The insertion of bis‐RhI metal ion in the macrocyclic core affords a singly twisted conformational structure. Furthermore, the local aromaticity in the bis‐4,4'‐biphenyl ring dominates the overall macrocyclic aromaticity in all three forms, and thus adopts nonaromatic characteristics. These results are supported by spectral as well as theoretical studies, and they are unambiguously confirmed by X‐ray crystal analyses.