bluuebunny/crossref_metadata_2025 huggingface dataset:
The Contribution of Audit Committees in the Reduction of the Liquidity Risk Levels in the Jordanian Commercial Banks
Authors: Al-Hajaia Mohammad , Hashem Firas
Published: September 2018

This study aimed to identify the extent of the audit committees’ contribution in the reduction of the liquidity risk levels in the Jordanian commercial banks. The current study also aimed to identify whether there are any statistically significant differences between the extent of the audit committees’ contribution in the reduction of the liquidity risk levels in the Jordanian commercial banks that can be attributed to the auditor’s years of experience and academic qualification. As for the population of the current study, it consisted of all the internal auditors working in the Jordanian commercial banks. As for the sample, it consisted of forty (40) internal auditors working in Jordanian commercial banks.

The Researcher has concluded the following results:

 Audit committees participate in reducing the liquidity risk levels in the Jordanian commercial banks.

There are statistically significant differences between the extent of the audit committees’ contribution in the reducing the liquidity risk levels in the Jordanian commercial banks which can be attributed to the auditor’s experience.

There are no statistically significant differences between the extent of the audit committees’ contribution in the reduction of the liquidity risk levels in the Jordanian commercial banks which can be attributed to the auditor’s academic qualification.

The researcher has suggested the following recommendations:

The researcher of the current study recommended providing more attention to developing the work performance of internal auditors in the Jordanian commercial banks. That shall be done in the aim of raising the accuracy and reliability of the financial statements they make.

The researcher of the current study recommended encouraging internal auditors to comply with the principles of accuracy and reliability in their financial statements in Jordanian commercial banks. The researcher also recommended promoting this to be their dominant way of thinking

The researcher of the current study recommended developing the internal auditors’ performance in using the advanced information systems. That shall be done in the aim of raising the accuracy and reliability of their financial statements to reduce the liquidity risk levels.

The researcher of the current study recommended conducting more studies about the same matter with applying them on other sectors.
Production and Evaluation of Biscuits Made From Wheat Flour and Toasted Watermelon Seed Meal as Fat Substitute
Authors: Peter-Ikechukwu A. I. , Omeire G. C. , Kabuo N. O. , Eluchie C. N. , Amandikwa C. , Odoemenam G. I.
Published: September 2018

Production and evaluation of biscuits made from wheat flour and toasted watermelon seed meal as fat substitute was studied. Extracted watermelon seeds were toasted and grounded into seed meal, which were later usedto formulate composite flour blends in the ratio of 10:90 (MW1), 20:80 (MW2), 30:70 (MW3), 40:60 (MW4) with and 50:50 (MW5) of water melon seed meal: wheat flour respectively, while 100% wheat flour served as control (W1). Each blend was used to produce biscuits adopting robbing process. The functional properties of flour blends, proximate composition and physical properties of the biscuit samples were determined. Sensory qualities of the biscuits were evaluated by 20-members panelist. The accepted composite biscuit samples was stored on a shelf for 6 weeks and analyzed for moisture and total viable count. Data obtained were analyzed statistically (P≤0.05) for ANOVA, and means separated using Fisher’s LSD Test. The results of the functional properties showed variations in behaviour. There were no significant differences (P≤0.05) in pH, swelling index, viscosity and gelation temperature of the flour blends while significant differences ‘(P≤0.05) existed in bulk density, water absorption capacity and wetability. There were significant differences (P≤0.05) in protein, fat, crude fibre, ash and carbohydrate for both flour blends and biscuit samples respectively. The addition of toasted watermelon seed meal increased protein, fat, crude fibre and ash contents while carbohydrate content decreased with higher substitution level of wheat flour. Moisture content ranged from 10-11 % (flour) and 6.25 -10% (biscuit). Significant differences (P≤0.05) were recorded in thickness, spread ratio and break strength within the samples. The result of sensory evaluation showed that W1I was significantly different (P≤0.05) in taste, aroma and overall acceptance.

However, MW4 and MW5 were significantly different in texture, but in terms of crispiness, MW1 and MW3 were preferred. Moisture content of the preferred samples (MW1 and MW3) stored for 6 weeks increased from 6.25-11.75 % (MW1) and 6.75 – 11.0% (MW3) while the viable microbial counts ranged from 2.0 x 102-6.8 x 105cfu/g for bacteria and 1.8 x 101-7.4 x 103cfu/g for mould respectively.
Results of cystadenolymphoma treatment of superficial parotid gland
Authors: Ślęzak Aleksandra , Kaźmierczak Wojciech , Kaźmierczak Henryk
Published: September 2018

Guz Warthina jest niezłośliwym nowotworem występującym w dużych gruczołach ślinowych. Diagnostyka obejmuje badanie podmiotowe, przedmiotowe oraz badania dodatkowe - ultrasonografię, badanie tomografii rezonansu magnetycznego, biopsję aspiracyjną cienkoigłową. Metodą leczenia pozostaje chirurgiczna resekcja guza, której zakres obejmuje techniki od zewnątrztorebkowego usunięcia guza do pełnego wachlarza parotidektomii. Materiał i metody Dokonano retrospektywnej analizy dostępnej dokumentacji medycznej 53 chorych leczonych chirurgicznie w Klinice Otolaryngologii i Onkologii Laryngologicznej Collegium Medicum Uniwersytetu Mikołaja Kopernika w Toruniu w latach 2009-2016. U każdego chorego wykonano badanie podmiotowe, przedmiotowe oraz zlecono rutynową ocenę ultrasonograficzną. Uzyskane wyniki leczenia 57 guzów poddano analizie. Wyniki Niniejsze badanie wykazało, że w przypadku zastosowania techniki zewnątrztorebkowego usunięcia guza w leczeniu guzów Warthina dolnego bieguna płata powierzchownego ślinianki przyusznej u 57 chorych nie obserwowano powikłań pod postacią: trwałego niedowładu czy porażenia nerwu twarzowego, torbieli ślinowych, objawów zespołu Łucji-Frey czy defektu kosmetycznego twarzy. U 8 (14%) chorych w badaniu ultrasonograficznym uwidoczniono zmiany wymagające dalszej diagnostyki lub okresowej ultrasonograficznej kontroli.
Finite Element Analysis of Dynamic Fracture Behaviour of Drill Pipe Under Various Impact Loads
Authors: ZHAO Guanghui , ZHAO Li , ZHANG Y. X. , LI Ju
Published: September 2018

In this paper, finite element analysis is conducted to study dynamic responses of a defected drill pipe (DP) under impact loading encountered in working conditions. Longitudinal impact loading such as tensile, eccentric compressive and torsional impact loading and transverse collision loading are considered. A finite element model is firstly developed and validated, and then employed to evaluate the effects of various impact loading on dynamic responses of the defected DP. It is found that the inertial effect due to tensile impact is the most prominent among all the longitudinal impact loadings. In addition, the effect of the transverse collision between the DP and the borehole wall on the driving force of the crack is evaluated. It is concluded that the dynamic effects of the various impact loading frequently exerting on the DP should be taken into consideration for life prediction of DPs. DOI: http://dx.doi.org/10.5755/j01.mech.24.4.19503
Digital Image Correlation in Ioscipescu Shear Test
Authors: Grzesiak Michał Jerzy , KOWALIK Michał , SUPRYNOWICZ Karol
Published: September 2018

This paper presents investigation of using Digital Image Correlation measurement method in Ioscipescu Shear Test. Additionally a FEM model was developed to further support research and to be used in future investigation. Test specimens were made of Polymethyl methacrylate (PMMA), an isotropic material which shear test results can be compared with calculated shear modulus from the tensile test. FEM model was developed as 2D linear model with thickness as parameter. In development the linear model was dropped in favor of model with contact and friction that gave better results. The results of shear test compared to the shear modulus calculated from tensile test, gave matching results. FEM model due to inclusion friction mechanism required calibration, therefore its accuracy was confirmed by strain measurements. Overall both experiment and FEM model worked its purpose.DOI: http://dx.doi.org/10.5755/j01.mech.24.4.20301
Thinking, Deciding, Acting: Gaps and Relations
Authors: Diržytė Aistė
Published: September 2018

In the first part of this essay the author points to possible gaps and relations between cognitive (thinking, reasoning, decision making) and behavioural (acting) processes. Mainstream cognitive sciences assume that thinking might result in decision making which might result in acting: i.e. cognitive processes are related to behavioural processes. Perceptual distortion, inaccurate judgment, illogical interpretation, or what is broadly called irrationality might lead to destructive behaviours on personal or societal levels. It is noted that some researchers focus on mediating/moderating factors and correlations between thinking, decision making and acting, while others focus on gaps. In the second part the author reviews the articles presented in this issue and questions as they have been discussed by others: heuristics as a method that uses principles of effort-reduction and simplification, hermeneutics of values based on Max Weber concepts, Bakhtin’s ideas on philosophy of the act and diachronic, dialogistic linguistic activities, phenomenology of solidarity implying that the acts determine experience of the world in modi ‘we’, Heidegger’s thinking, assuming the vital link between practical and ontological aspects of Heideggerian phenomenology, the evidence on theory and practice of new media and the development of concepts of creativity.
An Outline of a Phenomenology of Solidarity: Beyond the Bridge Problem
Authors: Płotka Witold
Published: September 2018

The aim of the article is to present main elements, problems and preliminary solutions connected to a phenomenology of solidarity. The article is divided into three parts. In the first part, the author defines the bridge problem as an attempt to bind subjective and intersubjective levels of constitution, and he shows that neither Ingarden nor Tischner can solve the problem. In the second part, the author presents the act of solidarization as a complex act which binds cognitive, volitional and affective dimensions. Finally, the author sketches an alternative approach to a phenomenology of solidarity that leads beyond the bridge problem, namely, Husserl’s theory of constitution of groups in joint action.
The Formation of the Concept of Television Media: The Phenomenon of Direct Broadcast
Authors: Pečiulis Žygintas
Published: September 2018

For the first time, television was shown more than 90 years ago, and TV as the media began to entrench in the 1930s. The emergence of the new media reveals the old–new contraposition when the new communication technology is trying to interfere with the established system. The look at the era of the emergence of new media is not only a historical tour but also an opportunity to take a fresh look at today’s media and to predict their development.
This text analyses the 1930s–1960s scripts from the Paris Saint-Genevieve Library Funds about the theory and critique of Western TV. Our goal is to reveal how the new media is perceived in texts of those days, with a particular attention to the effects of direct broadcast.
Peptidoglycan precursor synthesis along the sidewall of pole-growing mycobacteria
Authors: García-Heredia Alam , Pohane Amol Arunrao , Melzer Emily S , Carr Caleb R , Fiolek Taylor J , Rundell Sarah R , Lim Hoong Chuin , Wagner Jeffrey C , Morita Yasu S , Swarts Benjamin M , Siegrist M Sloan
Published: September 2018

Rod-shaped mycobacteria expand from their poles, yet d-amino acid probes label cell wall peptidoglycan in this genus at both the poles and sidewall. We sought to clarify the metabolic fates of these probes. Monopeptide incorporation was decreased by antibiotics that block peptidoglycan synthesis or l,d-transpeptidation and in an l,d-transpeptidase mutant. Dipeptides complemented defects in d-alanine synthesis or ligation and were present in lipid-linked peptidoglycan precursors. Characterizing probe uptake pathways allowed us to localize peptidoglycan metabolism with precision: monopeptide-marked l,d-transpeptidase remodeling and dipeptide-marked synthesis were coincident with mycomembrane metabolism at the poles, septum and sidewall. Fluorescent pencillin-marked d,d-transpeptidation around the cell perimeter further suggested that the mycobacterial sidewall is a site of cell wall assembly. While polar peptidoglycan synthesis was associated with cell elongation, sidewall synthesis responded to cell wall damage. Peptidoglycan editing along the sidewall may support cell wall robustness in pole-growing mycobacteria.
An integrated platform for intuitive mathematical programming modeling using LaTeX
Authors: Triantafyllidis Charalampos P. , Papageorgiou Lazaros G.
Published: September 2018

This paper presents a novel prototype platform that uses the same LaTeX mark-up language, commonly used to typeset mathematical content, as an input language for modeling optimization problems of various classes. The platform converts the LaTeX model into a formal Algebraic Modeling Language (AML) representation based on Pyomo through a parsing engine written in Python and solves by either via NEOS server or locally installed solvers, using a friendly Graphical User Interface (GUI). The distinct advantages of our approach can be summarized in (i) simplification and speed-up of the model design and development process (ii) non-commercial character (iii) cross-platform support (iv) easier typo and logic error detection in the description of the models and (v) minimization of working knowledge of programming and AMLs to perform mathematical programming modeling. Overall, this is a presentation of a complete workable scheme on using LaTeX for mathematical programming modeling which assists in furthering our ability to reproduce and replicate scientific work.
Effects of environmental and anthropogenic landscape features on mule deer harvest in Nebraska
Authors: O’Connor Bryan J. , Fryda Nicolas J. , Ranglack Dustin H.
Published: September 2018

Understanding the habitat use of wildlife species is important for effective management. Nebraska has a variety of habitat types, with the majority being covered by rangeland and cropland. These habitat types likely influence the harvest of mule deer (MD; Odocoileus hemionus) in Nebraska, but their specific effects are unknown, and moreover, harvest may also be influenced by the accessibility of deer habitats for hunters. We modeled which environmental and anthropogenic landscape features influenced harvest densities. Spatial analysis in a Geographic Information System was used to determine the mean values of environmental and anthropogenic landscape features at the county level. We then used a generalized linear model to determine which of those factors influenced MD harvest from 2014–2016. We found that NDVI amplitude, hunter effort, road density, terrain roughness, and canopy cover influence MD harvest in Nebraska. According to our model, MD harvest densities are significantly greater areas with NDVI amplitude ∼38, increasing hunter effort, road densities near 1,750 m/km2, increasing terrain roughness, and decreasing canopy cover. Understanding increased harvest densities of MD can be beneficial for wildlife managers, allowing for more efficient allocation of efforts and expenses by managers for population management.
Persistência de imazethapyr no solo e toxicidade ao milho semeado em sucessão
Authors: Carvalho Saul Jorge Pinto de , Soares Daniel Jorge , López Ovejero Ramiro Fernando , Christoffoleti Pedro Jacob
Published: September 2018

Este trabalho foi desenvolvido com o objetivo de avaliar a persistência do herbicida imazethapyr no solo, bem como a toxicidade à cultura do milho cultivado em sucessão. Os tratamentos foram organizados em esquema fatorial com dois tipos de solo (S; argiloso e arenoso), três regimes de irrigação (I; diário, semanal e ausente) e quatro épocas (E) de aplicação do produto (90, 60 e 30 dias anteriores à semeadura do milho, além de testemunha sem aplicação). Para tanto, o herbicida imazethapyr foi aplicado na dose única de 100 g ha-1. Foi adotado delineamento de blocos ao acaso com quatro repetições, totalizando 96 parcelas. Cada parcela foi caracterizada por um vaso de 8,5 L, preenchido com solo peneirado. Em síntese, a adequada disponibilidade hídrica entre a aplicação do produto e a semeadura do milho garantiu menores níveis de toxicidade à cultura e maior produção de massa de matéria seca. Em solo argiloso foram observados os menores níveis de toxicidade à cultura. A persistência do produto no solo foi reduzida sempre que ocorreu maior atividade microbiana, favorecida pela temperatura, disponibilidade de água no ambiente e, em menor grau, pelo tempo de persistência do produto no solo.
Tunable Assembly of Protein‐Microdomains in Living Vertebrate Embryos
Authors: Li Zhe , Tyrpak David R. , Lien Ching‐Ling , MacKay John Andrew
Published: September 2018

Subcellular events such as trafficking and signaling are regulated by self‐assembled protein complexes inside the cell. The ability to rapidly and reversibly manipulate these protein complexes would likely enhance studies of their mechanisms and their roles in biological function and disease manifestation. This paper reports that thermally responsive elastin‐like polypeptides (ELPs) linked to fluorescent proteins can regulate the self‐assembly and disassembly of protein microdomains within the individual cells of zebrafish embryos. By exploring a library of fluorescent ELP proteins, this report demonstrates that ELPs can coassemble different fluorescent proteins inside of embryos. By tuning ELP length and sequence, fluorescent protein microdomains can be assembled at different temperatures, in varying sizes, or for desired periods of time. For the first time in a multicellular living embryo, these studies demonstrate that temperature‐mediated ELP assembly can reversibly manipulate assembly of subcellular protein complexes, which may have applications in the study and manipulation of in vivo biological functions.
Effect of Dispersoids on the Microstructure Evolution in Al–Mg–Si Alloys
Authors: Kenyon Michael , Robson Joseph , Fellowes Jonathan , Liang Zeqin
Published: September 2018

An Al–Mg–Si alloy with a high level of Cr is investigated via Electron Probe Micro Analysis (EPMA) and Scanning Transmission Electron Microscopy (STEM). EPMA is conducted on the same area of a sample after numerous heat treatments in a vacuum furnace to study the evolution of Mg, Si, Cr, and Fe from the segregated structure formed on casting. Mg and Si are found to segregate toward the grain boundaries and remained segregated up to 550 °C. Cr segregates away from the grain boundaries. Regions of lower Cr separated from high Cr regions by sharp transitions are observed. To investigate the effect of segregation on dispersoid precipitation, samples are heated to a number of different temperatures and examined using STEM. The evolution of dispersoid area fraction and effective diameter is measured as a function of position within a grain. The dispersoid area fraction decreases, while the size initially decreases and then increases toward the grain center. Both α‐Al(FeCr)Si and α′‐AlCrSi dispersoids exist with a variety of morphologies. The α′‐AlCrSi dispersoids are found to have a larger effective diameter. The change in dispersoids fraction, size, and morphology with position has important implications for the pinning effectiveness of the dispersoids against recrystallization.
Protein‐Engineered Biomaterials for Cancer Theranostics
Authors: Liu Xiaowen , Wang Chao , Liu Zhuang
Published: September 2018

Proteins are an important class of biomaterials promising a variety of applications such as drug delivery, and imaging or therapy, owing to their biodegradability, biocompatibility, as well as inherent biological activities acting as enzymes, recognizing molecules, or therapeutics by themselves. Over the few past decades, different types of proteins with desired properties have been widely explored for biomedical applications. Many therapeutic proteins have now entered clinical use. This review therefore summarizes various strategies in the engineering of biomaterials for delivery of therapeutic proteins, as well as the recent development of protein‐based biomaterials for cancer theranostics.
Recent Progress in Solid‐State Nanopores
Authors: Lee Kidan , Park Kyeong‐Beom , Kim Hyung‐Jun , Yu Jae‐Seok , Chae Hongsik , Kim Hyun‐Mi , Kim Ki‐Bum
Published: September 2018

The solid‐state nanopore has attracted much attention as a next‐generation DNA sequencing tool or a single‐molecule biosensor platform with its high sensitivity of biomolecule detection. The platform has advantages of processability, robustness of the device, and flexibility in the nanopore dimensions as compared with the protein nanopore, but with the limitation of insufficient spatial and temporal resolution to be utilized in DNA sequencing. Here, the fundamental principles of the solid‐state nanopore are summarized to illustrate the novelty of the device, and improvements in the performance of the platform in terms of device fabrication are explained. The efforts to reduce the electrical noise of solid‐state nanopore devices, and thus to enhance the sensitivity of detection, are presented along with detailed descriptions of the noise properties of the solid‐state nanopore. Applications of 2D materials including graphene, h‐BN, and MoS2 as a nanopore membrane to enhance the spatial resolution of nanopore detection, and organic coatings on the nanopore membranes for the addition of chemical functionality to the nanopore are summarized. Finally, the recently reported applications of the solid‐state nanopore are categorized and described according to the target biomolecules: DNA‐bound proteins, modified DNA structures, proteins, and protein oligomers.
Clarification of the Molecular Doping Mechanism in Organic Single‐Crystalline Semiconductors and their Application in Color‐Tunable Light‐Emitting Devices
Authors: Ding Ran , Wang Xue‐Peng , Feng Jing , Li Xian‐Bin , Dong Feng‐Xi , Tian Wei‐Quan , Du Jia‐Ren , Fang Hong‐Hua , Wang Hai‐Yu , Yamao Takeshi , Hotta Shu , Sun Hong‐Bo
Published: September 2018

Organic single‐crystalline semiconductors with long‐range periodic order have attracted much attention for potential applications in electronic and optoelectronic devices due to their high carrier mobility, highly thermal stability, and low impurity content. Molecular doping has been proposed as a valuable strategy for improving the performance of organic semiconductors and semiconductor‐based devices. However, a fundamental understanding of the inherent doping mechanism is still a key challenge impeding its practical application. In this study, solid evidence for the “perfect” substitutional doping mechanism of the stacking mode between the guest and host molecules in organic single‐crystalline semiconductors using polarized photoluminescence spectrum measurements and first‐principles calculations is provided. The molecular host–guest doping is further exploited for efficient color‐tunable and even white organic single‐crystal‐based light‐emitting devices by controlling the doping concentration. The clarification of the molecular doping mechanism in organic single‐crystalline semiconductor host–guest system paves the way for their practical application in high‐performance electronic and optoelectronic devices.
Plasmonic Chirality and Circular Dichroism in Bioassembled and Nonbiological Systems: Theoretical Background and Recent Progress
Authors: Kong Xiang‐Tian , Besteiro Lucas V. , Wang Zhiming , Govorov Alexander O.
Published: September 2018

Nature is chiral, thus chirality is a key concept required to understand a multitude of systems in physics, chemistry, and biology. The field of optics offers valuable tools to probe the chirality of nanosystems, including the measurement of circular dichroism, the differential interaction strength between matter and circularly polarized light with opposite helicity. Simultaneously, the use of plasmonic systems with giant light‐interaction cross‐sections opens new paths to investigate and manipulate systems on the nanoscale. Consequently, the interest in chiral plasmonic and hybrid systems has continually grown in recent years, due to their potential applications in biosensing, polarization‐encoded optical communication, polarization‐selective chemical reactions, and materials with polarization‐dependent light–matter interaction. Experimentally, chiral properties of nanostructures can be either created artificially using modern fabrication techniques involving inorganic materials, or borrowed from nature using bioassembly or biomolecular templating. Herein, the recent progress in the field of plasmonic chirality is summarized, with a focus on both the theoretical background and the experimental advances in the study of chirality in various systems, including molecular‐plasmonic assemblies, chiral plasmonic nanostructures, chiral assemblies of interacting plasmonic nanoparticles, and chiral metal metasurfaces and metamaterials. The growth prospects of this field are also discussed.
Design of Highly Efficient Thermoelectric Materials: Tailoring Reciprocal‐Space Properties by Real‐Space Modification
Authors: Zhu Hao , Xiao Chong , Xie Yi
Published: September 2018

Although restricted by the poor performance at present, thermoelectric materials for power‐generation devices and solid‐state Peltier coolers still possess unlimited vitality, thus capturing considerable attention. Understanding and manipulating the electrical and thermal transport mechanisms in thermoelectrics play significant roles in tailoring the properties of various thermoelectric materials. The transport behavior of electrons and phonons are closely related to the chemical composition and structure, which are defined in real space. Meanwhile, transport properties are also contingent on the band structure and phonon spectrum, both of which are represented in the reciprocal‐space first Brillouin zone. Real space and reciprocal space are bridged by the Fourier transform, and the combination of real‐space and reciprocal‐space properties will provide more possibilities for regulating transport characteristics. Herein, a compendious discussion of the internal connection between real space and reciprocal space, and the underlying physics and chemistry is presented. Then, how the relationship between real and reciprocal space provides additional insights to govern electrical and thermal transport parameters is elaborated upon, thereby enabling the discovery and optimization of thermoelectric materials. In conclusion, specific challenges and feasible directions are discussed.
Josephson Effect in a Few‐Hole Quantum Dot
Authors: Ridderbos Joost , Brauns Matthias , Shen Jie , de Vries Folkert K. , Li Ang , Bakkers Erik P. A. M. , Brinkman Alexander , Zwanenburg Floris A.
Published: September 2018

A Ge–Si core–shell nanowire is used to realize a Josephson field‐effect transistor with highly transparent contacts to superconducting leads. By changing the electric field, access to two distinct regimes, not combined before in a single device, is gained: in the accumulation mode the device is highly transparent and the supercurrent is carried by multiple subbands, while near depletion, the supercurrent is carried by single‐particle levels of a strongly coupled quantum dot operating in the few‐hole regime. These results establish Ge–Si nanowires as an important platform for hybrid superconductor–semiconductor physics and Majorana fermions.
Rich Chemistry in Inorganic Halide Perovskite Nanostructures
Authors: Huang Jianmei , Lai Minliang , Lin Jia , Yang Peidong
Published: September 2018

Halide perovskites have emerged as a class of promising semiconductor materials owing to their remarkable optoelectronic properties exhibiting in solar cells, light‐emitting diodes, semiconductor lasers, etc. Inorganic halide perovskites are attracting increasing attention because of the higher stability toward moisture, light, and heat as compared with their organic–inorganic hybrid counterparts. In particular, inorganic halide perovskite nanomaterials provide controllable morphology, tunable optoelectronic properties, and improved quantum efficiency. Here, the development controlled synthesis of desired inorganic halide perovskite nanostructures by various chemical approaches is described. Utilizing these nanostructures as platforms, anion exchange chemistry for wide compositional and optical tunabilities is described, and the rich structural phase transition phenomenon and mechanism investigated systematically. Furthermore, these nanostructures and extracted knowledge are applied to design photonic, photovoltaic, and thermoelectric devices. Finally, future directions and challenges toward improvement of the optical, electrical, and optoelectronic properties, exploration of the anion and cation exchange kinetics, and alleviation of the stability and toxicity issues in inorganic lead based halide perovskites are discussed to provide an outlook on this promising field.
Dynamic Visualization of Stress/Strain Distribution and Fatigue Crack Propagation by an Organic Mechanoresponsive AIE Luminogen
Authors: Qiu Zijie , Zhao Weijun , Cao Mingkui , Wang Yuqi , Lam Jacky W. Y. , Zhang Zhe , Chen Xu , Tang Ben Zhong
Published: September 2018

Stress exists ubiquitously and is critically important for the manufacturing industry. Due to the ultrasensitive mechanoresponse of the emission of 1,1,2,2,‐tetrakis(4‐nitrophenyl)ethane (TPE‐4N), a luminogen with aggregation‐induced emission characteristics, the visualization of stress/strain distributions on metal specimens with a pure organic fluorescent material is achieved. Such a fluorescence mapping method enjoys the merits of simple setup, real‐time, full‐field, on‐site, and direct visualization. Surface analysis shows that TPE‐4N can form a nonfluorescent, crystalline uniform film on the metal surface, which cracks into fluorescent amorphous fragments upon mechanical force. Therefore, the invisible information of the stress/strain distribution of the metal specimens are transformed to visible fluorescent signals, which generally matches well but provides more details than software simulation. Remarkably, fatigue crack propagation in stainless steel and aluminum alloy can be observed and predicted clearly, further demonstrating the ultrasensitivity and practicability of TPE‐4N.
A Dual‐Crosslinking Design for Resilient Lithium‐Ion Conductors
Authors: Lopez Jeffrey , Sun Yongming , Mackanic David G. , Lee Minah , Foudeh Amir M. , Song Min‐Sang , Cui Yi , Bao Zhenan
Published: September 2018

Solid‐state electrolyte materials are attractive options for meeting the safety and performance needs of advanced lithium‐based rechargeable battery technologies because of their improved mechanical and thermal stability compared to liquid electrolytes. However, there is typically a tradeoff between mechanical and electrochemical performance. Here an elastic Li‐ion conductor with dual covalent and dynamic hydrogen bonding crosslinks is described to provide high mechanical resilience without sacrificing the room‐temperature ionic conductivity. A solid‐state lithium‐metal/LiFePO4 cell with this resilient electrolyte can operate at room temperature with a high cathode capacity of 152 mAh g−1 for 300 cycles and can maintain operation even after being subjected to intense mechanical impact testing. This new dual crosslinking design provides robust mechanical properties while maintaining ionic conductivity similar to state‐of‐the‐art polymer‐based electrolytes. This approach opens a route toward stable, high‐performance operation of solid‐state batteries even under extreme abuse.
An Efficient Ga(OTf)3/Isopropanol Catalytic System for Direct Reduction of Benzylic Alcohols
Authors: Sai Masahiro
Published: September 2018

This study aims to report the first gallium‐catalyzed direct reduction of benzylic alcohols using isopropanol as a reductant. The reaction proceeds via gallium catalyst‐assisted hydride transfer of the in situ‐generated benzylic isopropyl ether. The method generates only water and acetone as byproducts and thus provides an atom‐economic and environmentally friendly approach to the synthesis of di‐ and triarylmethanes, which are important substructures in various bioactive compounds and functional materials.

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Low‐Temperature Processable High‐Performance D–A‐Type Random Copolymers for Nonfullerene Polymer Solar Cells and Application to Flexible Devices
Authors: Kim Ji‐yeong , Park Sungmin , Lee Seungjin , Ahn Hyungju , Joe Sung‐yoon , Kim Bumjoon J. , Son Hae Jung
Published: September 2018

Donor–acceptor random copolymers incorporating 1,3‐bis(thiophen‐2‐yl)‐5,7‐bis(2‐ethylhexyl)benzo[1,2‐c:4,5‐c′]dithiophene‐4,8‐dione (BDD) and 4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b:4,5‐b′]dithiophene (BDT‐Th) are developed. Nonfullerene solar cells introducing the random copolymer PBDB‐T73 (BDT‐Th:BDD=7:3) and 3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone))‐5,5,11,11‐tetrakis(4‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene are found to exhibit efficiency of 11.14%, which is superior to that of the PBDB‐T alternating copolymer (10.02%). The PBDB‐T73 device exhibits high performance due to low bimolecular charge recombination and good charge transport balance even though none of the treatments that are usually necessary for improving crystalline properties of active layers are performed; in contrast, the PBDB‐T device requires thermal annealing in order to enhance the polymer's crystallinity and obtain improved fill factor and Jsc values. It is demonstrated that efficient charge transport occurs in the PBDB‐T73 blend despite relatively low crystallinity of the polymer. The percolating network structure of the large mixed phase in the PBDB‐T73 blend has an important role in its efficient charge transport. Moreover, due to the low‐temperature processability of PBDB‐T73, flexible PBDB‐T73 solar cell devices prepared on polyethylene terephthalate (PET) substrates exhibit high photovoltaic performance, 10.02%, whereas the efficiency of PBDB‐T‐based flexible devices (7.2%) is significantly lower due to damage to the active layer on indium tin oxide (ITO)/PET that results from thermal annealing.
Efficiency Exceeding 20% in Perovskite Solar Cells with Side‐Chain Liquid Crystalline Polymer–Doped Perovskite Absorbers
Authors: Arivunithi Veera Murugan , Reddy Saripally Sudhaker , Sree Vijaya Gopalan , Park Ho‐Yeol , Park Juuyn , Kang Yong‐Cheol , Shin Eun‐Sol , Noh Yong‐Young , Song Myungkwan , Jin Sung‐Ho
Published: September 2018

Attaining high quality perovskite films with enhanced morphology, high efficiency, and better stability is a great research challenge. Here, a side‐chain liquid crystalline polymer (SCLCP) is incorporated as a dopant into the perovskite film to achieve perovskite solar cells (PSCs) with high efficiency and long‐term stability. SCLCP doping increases the grain size in the crystalline perovskite film by controlled solvent evaporation and reduced grain boundaries, which slow the material degradation and reduce the charge recombination. Using this approach, the PSC power conversion efficiency (PCE) is significantly boosted from 18.0% (nondoped) to 20.63% for the SCLCP‐doped perovskite film with much improved air stability. Furthermore, the trap state density in the SCLCP‐doped films is decreased because the SCLCP effectively passivates the perovskite grain surface. Notably, the SCLCP appears to act as a bridge between grains for effective charge transfer from perovskite toward the electrode, which would partially explain the enhanced efficiency and stability.
Surgery for Pancreatic Cancer after neoadjuvant treatment
Authors: Hackert Thilo
Published: September 2018

Pancreatic ductal adenocarcinoma (PDAC) remains to be a therapeutic challenge as only 15%‐20% of all patients present with resectable tumor stages by the time of diagnosis. In the remaining patients, either local tumor extension or systemic spread are obstacles for a surgical therapy as the only chance for long‐term survival. With regard to local tumor extension, PDAC has been classified as resectable, borderline‐resectable (BR) or locally advanced (LA). While there is currently no evidence for neoadjuvant therapy in resectable PDAC, this issue remains controversial in BR‐PDAC. In the case of venous tumor involvement, guidelines mostly recommend upfront resection, when technically possible; whereas arterial involvement is regarded as an indication for chemotherapy or chemoradiotherapy first. Furthermore, in locally advanced PDAC, neoadjuvant treatment approaches have recently resulted in high rates of secondary resection, thus allowing “conversion” surgery in an otherwise palliative treatment situation. The present review gives an overview on the current literature of treatment concepts in these situations and additionally focuses of evaluation of resectability after neoadjuvant therapy as well as technical aspects in this specific situation.
Occupational exposures and parkinsonism among Shanghai women textile workers
Authors: Checkoway Harvey , Ilango Sindana , Li Wenjin , Ray Roberta M. , Tanner Caroline M. , Hu Shu‐Ching , Wang Xin , Nielsen Susan , Gao Dao L. , Thomas David B.
Published: September 2018

Background

Endotoxin, a contaminant of cotton dust, is an experimental model for parkinsonism (PS).

Methods

We investigated associations between exposures to endotoxin, solvents, magnetic fields, and night shift work, and neurologist‐determined PS among Shanghai women textile workers, including 537 retired cotton factory workers ages ≥50 years and an age‐matched reference group of 286 retired textile workers not exposed to cotton dust. Repeat exams were conducted 2.5 years after enrollment among 467 cotton workers and 229 reference workers.

Results

We identified 39 prevalent PS cases and 784 non‐cases. No consistent or statistically significant associations were observed for endotoxin, solvents, magnetic fields, or shift work with PS risk, severity, or progression.

Conclusions

Despite the null findings, additional studies of endotoxin exposure and risk of PS in other well‐characterized occupational cohorts are warranted in view of toxicological evidence that endotoxin is a pathogenic agent and its widespread occurrence in multiple industries worldwide.
2,7‐Dioctylbenzofuro[3,2‐b]benzofuran: An Organic Semiconductor with Two‐dimensional Transport Channels
Authors: Chen Daoliang , Li Jie , Ma Weimin , Li Baolin , Zhen Yonggang , Zhu Xiaozhang , Hu Wenping , Tsuji Hayato , Nakamura Eiichi
Published: September 2018

We report herein a synthesis of benzofuro[3,2‐b]benzofuran (BFBF) by an intramolecular Ullmann C−O coupling reaction. To tune the film forming ability and self‐assembling behaviour, the derivative possessing two alkyl chains, 2,7‐dioctylbenzofuro[3,2‐b]benzofuran (C8‐BFBF), was further prepared. The packing structures of these two compounds were studied by XRD analysis, showing a two‐dimensional (2D) stacking structure in the solid state. DFT calculations indicated that C8‐BFBF exhibited large transfer integrals along the two stacking directions. The OFET devices based on C8‐BFBF showed typical hole transport properties with mobility up to 0.076 cm2 V−1 s−1.
Strukturaufklärung von Spurenkomponenten durch Kombination von GC/MS, GC/IR, DFT‐Simulationen und Synthese – Salinilactone, neuartige bicyclische Lactone aus Salinispora Bakterien
Authors: Schlawis Christian , Kern Simone , Kudo Yuta , Grunenberg Jörg , Moore Bradley S. , Schulz Stefan
Published: September 2018

Die Analyse flüchtiger Verbindungen aus marinen Salinispora Bakterien führte zur Entdeckung einer neuen Klasse von Naturstoffen mit ungewöhnlichem Bicyclo[3.1.0]‐Lactongerüst. Die Kombination verschiedener analytischer Methoden, Computational Spectroscopy und Synthese erlaubte die zweifelsfreie Strukturaufklärung der Verbindungen, genannt Salinilactone, ohne aufwendige Isolation mit nur sub‐μg Substanzmengen. Die Verwendung zweier orthogonaler Kupplungsmethoden, GC/MS und Festphasen‐GC/IR, erlaubte die Erstellung einer Reihe von Strukturvorschlägen. Durch den Vergleich des experimentellen IR‐Spektrums mit DFT‐Simulationen wurde einer der Strukturvorschläge für die Synthese priorisiert. So konnten die Struktur und absolute Konfiguration der drei Lactone, Salinilactone A–C, bestätigt werden. Die Salinilactone sind strukturell eng mit den Verbindungen der A‐Faktor‐Klasse verwandt, Autoregulatoren aus Streptomyceten, und zeigen inhibitorische Aktivität gegenüber Salinispora und Streptomyces Bakterien.
Iridium‐Catalyzed Electrooxidative C−H Activation by Chemoselective Redox‐Catalyst Cooperation
Authors: Qiu Youai , Stangier Maximilian , Meyer Tjark H. , Oliveira João C. A. , Ackermann Lutz
Published: September 2018

Iridium‐catalyzed electrochemical C−H activation was accomplished within a cooperative catalysis manifold, setting the stage for electrooxidative C−H alkenylations through weak O‐coordination. The iridium‐electrocatalyzed C−H activation featured high functional‐group tolerance through assistance of a metal‐free redox mediator through indirect electrolysis. Detailed mechanistic insights provided strong support for an organometallic C−H cleavage and a synergistic iridium(III/I)/redox catalyst regime, enabling the use of sustainable electricity as the terminal oxidant with improved selectivity features.
MXene Aerogel Scaffolds for High‐Rate Lithium Metal Anodes
Authors: Zhang Xinyue , Lv Ruijing , Wang Aoxuan , Guo Wenqing , Liu Xingjiang , Luo Jiayan
Published: September 2018

Li metal is considered to be an ultimate anode for metal batteries owing to its extremely high theoretical capacity and lowest potential. However, numerous issues such as short lifespan and infinite volume expansion caused by the dendrite growth during Li plating/stripping hinder its practical usage. These challenges become more grievous under high current densities. Herein, 3D porous MXene aerogels are proposed as scaffolds for high‐rate Li metal anodes using Ti3C2 as an example. With high metallic electron conductivity, fast Li ion transport capability, and abundant Li nucleation sites, such scaffolds could deliver high cycling stability and low overpotential at current density up to 10 mA cm−2. High rate performance is also demonstrated in full cells with LiFePO4 as cathodes. This work provides a new type of scaffolds for Li metal anodes and paves the way for the application of non‐graphene 2D materials toward high energy density Li metal batteries.
Synthesis, characterization, and performance of a novel polycarboxylate superplasticizer with a crosslinked topological structure
Authors: Zhao Hongwei , Liao Bing , Wang Kun , Zhao Yangyang , Nian Fuwei , Meng Yeyun , Pang Hao
Published: September 2018

In this work, a novel crosslinked topological polycarboxylate superplasticizer (TPC) was successfully synthesized. In comparison with conventional comb‐shaped superplasticizer (CPC), the TPC performed better dispersion maintaining stronger water reduction capabilities. The TPC provided a large spherical space due to its crosslinked molecular structure, which was the main reason for enhanced dispersion performance. It was evident that the addition of TPC leads to a delayed and lowered heat flow peak during the early stage of the hydration process. Thermogravimetric analysis showed that the hydrated products exhibited a more stable performance in the presence of the TPC. Changing the molecular structure from a comb‐shape to a crosslinked topological could effectively improve the comprehensive performances of the PCs. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46716.
Dynamic mechanical and shape memory properties of copolymers based on polyetheramine‐type benzoxazines and diglycidylether of bisphenol‐A
Authors: Li Cuiyun , Shen Shanshan , Li Zhiyun , Zhen Hecheng , Huang Jinbai , Liu Yanfang
Published: September 2018

Two series of benzoxazine/epoxy copolymers are prepared from polyetheramine‐type benzoxazines and diglycidyl ether of bisphenol A (DGEBA) in various weight ratios. Each copolymer appears a single glass‐transition temperature (Tg), and theTgshows a systematic increase with increasing DGEBA content for both copolymer systems, but copolymers with low DGEBA content show respectively lowerTgs than the corresponding pristine polybenzoxazines. Compared to the corresponding pristine polybenzoxazines, the effect of DGEBA content on the variation inTgof the copolymers depends on the substituent structure of benzoxazines. The two series of copolymers exhibit one‐way dual shape memory effect based onTg, and the shape memory effect is affected by both the substituent structure of benzoxazines and the content of DGEBA. Under motion constraints in tensile deformation mode, copolymers with low DGEBA content exhibit high shape recovery ratios (91.0–96.1%) over the corresponding polybenzoxazines (84.5%), whereas copolymers with high DGEBA content show relatively low shape recovery ratios (75.0–84.7%). © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2018,135, 46838.
Synthesis of new functional hexamethyltrisiloxanes and telechelic polydimethylsiloxanes based on them
Authors: Drozdov F. V. , Cherkaev G. V. , Demchenko N. V. , Muzafarov A. M.
Published: September 2018

Oligo‐ and polysiloxanes with terminal functional groups are of great interest in terms of syntheses of siloxane‐containing block copolymers by various synthetic methods. In this study, synthesis of bifunctional di‐ and trisiloxanes with different terminal 4‐(phenylene ethylene) substituents was developed using hydrosilylation under mild reaction conditions. Six new trisiloxanes with different functional substituents can be produced either directly by hydrosilylation of 4‐substituted styrene derivatives or by consistent conversion of the homologues obtained. All the functional trisiloxanes synthesized are suitable as chain stoppers in the ring‐opening polymerization of cyclosiloxanes. We believe that synthesis not only of symmetrical oligosiloxanes but also of asymmetrical hydrodosiloxane‐containing analogues is a promising approach. Compounds of this kind will be in demand as precursors for the production of functional siloxane derivatives by the hydrosilylation reaction. Thus, symmetrical or asymmetrical telechelic oligo‐ or polydimethylsiloxanes with different functional groups are suitable as AA‐type blocks for further synthesis of block copolymers. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2018,135, 46848.