bluuebunny/crossref_metadata_2025 huggingface dataset:
Murambi, le livre des ossements ou la question du jugement
Authors: Semujanga Josias
Published: January 2020

Les études sur les génocides et la Shoah privilégient le témoignage, au détriment des mécanismes narratifs mis en oeuvre. Cet article propose une analyse de la mise en abyme du jugement dans Murambi, le livre des ossements de Boubacar Boris Diop, roman-reportage sur le génocide des Tutsi au Rwanda. Je suggère que sa dimension testimoniale relève non seulement de son champ sémantique, mais également de ses plans narratif et énonciatif. Des procédés narratifs y sont déployés, mettant en scène une situation de procès où bourreau, victime et juge se font face. Dans ce roman d’horreur, Siméon Habineza émerge, figure du juste opposé à toute forme d’extrémisme, comme le véritable héros du roman. Au contraire des autres membres de sa tribu, il refuse de participer au génocide, et, après la guerre, combat la vengeance. À la différence des autres romans de l’auteur, qui sont des tragédies dont aucun héros n’émerge, dans Murambi, héros et antihéros sont identifiés. Cette forme mélodramatique suggère qu’un roman sur un génocide ne saurait rester neutre sur le plan des valeurs.
Im Kopf oder im Diskurs: wo ist unsere Welt? Sprache und Denken
Authors: Teubert Wolfgang
Published: January 2020

We only know how people understand what is being said or written once they have told us. Undoubtedly, understanding also includes non-linguistic or pre-linguistic components that elude verbalisation and thus cannot be communicated. However, by participating in discourse we can make sense of our experiences since we can perceive it in terms used by other participants talking about theirs. Experience that cannot be grasped linguistically remains mute. Therefore, as I see it, only what is textually accessible can be the remit of discourse analysis. This distinguishes discourse analysis from the cognitive approach whose remit it is to extrapolate from what is said to the mental representations, and to design the innate and acquired thought processes to which they owe their emergence. As I understand the cognitive approach of Alexander Ziem and Björn Fritsche, working with Dietrich Busse’s frame concept, they cannot but fail to convincingly model the presumed cognitive processes. For though they insist that a “cognitive-constructive share” complements the formation of mental representations, they must concede that it is ultimately the discursively constituted categories that determine how we experience reality. What matters for us as members of a discourse community is less what happens in our heads than how we, by talking about it, discursively create our reality, both as individuals as well as collectively.
Dyskurs medialny w ujęciu kulturowym
Authors: Żydek-Bednarczuk Urszula
Published: January 2020

The article refers to the theory of colour, the theory of perception, contemporary media morphosis and the postulates of multimedia stylistics. The author undertakes the presented deliberations for two reasons. Perception, remembering and learning are important for the teaching process at the university regardless of the passage of time. Both the lecturer and the student are interested in the effective acquisition of content. Multimodality as an attribute of the prevailing products of contemporary culture should be the subject of interest for discourse linguistics.
The author’s research goal is to examine the effectiveness of font colours used in academic Power Point slides.
In a multimedia presentation as a form of a lecture, a public reception takes place, alongside listening with reading and watching. The synergy of the spoken word and the bit-based text occurs. The author puts forward the claim that colour can be a factor in supporting or losing the listener’s directional attention. The second claim is that a colourful area, or a background for a printed text, is different from the colour of the font used in a text that students are required to read and watch from a distance.
When the lecturer stands in front of the audience, they can manage its attention through various means. One of them is visualization in the form of the font colour choice within the slide.
The article is a proposal of a certain type of research, but the author also presents the results of an experiment. Its results allow to reject the dominant role of the text placed on the slide. Some students correctly recalled the information conveyed only in the spoken form.
A multi-criteria optimization approach to modeling negotiation process
Authors: Łodziński Andrzej
Published: January 2020

The paper presents a multi-criteria optimization approach to modeling negotiation process. The negotiation process is modeled as a special multi-criteria problem. The method for finding solutions is the interactive selection process of some proposals. The parties shall submit their proposals on the subjects of the negotiations. These proposals are parameters of the multi-criteria optimization problem. Selection of solutions is accomplished by solving the optimization problem with parameters that define the aspirations of each party involved in the negotiations. Finally, evaluation of the solutions obtained by the parties is made.
Rapid digitization to reclaim thematic maps of white-tailed deer density from 1982 and 2003 in the conterminous US
Authors: Hanberry Brice , Hanberry Phillip
Published: January 2020

Background

Despite availability of valuable ecological data in published thematic maps, manual methods to transfer published maps to a more accessible digital format are time-intensive. Application of object-based image analysis makes digitization faster.

Methods

Using object-based image analysis followed by random forests classification, we rapidly digitized choropleth maps of white-tailed deer (Odocoileus virginianus) densities in the conterminous US during 1982 and 2001 to 2005 (hereafter, 2003), allowing access to deer density information stored in images.

Results

The digitization process took about one day each per deer density map, of which about two hours was computer processing time, which will differ due to factors such as resolution and number of objects. Deer were present in 4.75 million km2 (60% of the area) and 5.56 million km2 (70%) during 1982 and 2003, respectively. Population and density in areas with deer presence were 17.15 million and 3.6 deer/km2 during 1982 and 29.93 million and 5.4 deer/km2 during 2003. Greatest densities were 7.2 deer/km2 in Georgia during 1982 and 14.6 deer/km2 in Wisconsin during 2003. Six states had deer densities ≥9.8 deer/km2 during 2003. Colorado, Idaho, and Oregon had greatest increases in population and area of deer presence, and deer expansion is likely to continue into western states. Error in these estimates may be similar to error resulting from differential reporting by state agencies. Deer densities likely are within historical levels in most of the US.

Discussion

This method rapidly reclaimed informational value of deer density maps, enabling greater analysis, and similarly may be applied to digitize a variety of published maps to geographic information system layers, which permit greater analysis.
High variability within pet foods prevents the identification of native species in pet cats’ diets using isotopic evaluation
Authors: McDonald Brandon W. , Perkins Troi , Dunn Robert R. , McDonald Jennifer , Cole Holly , Feranec Robert S. , Kays Roland
Published: January 2020

Domestic cats preying on wildlife is a frequent conservation concern but typical approaches for assessing impacts rely on owner reports of prey returned home, which can be biased by inaccurate reporting or by cats consuming prey instead of bringing it home. Isotopes offer an alternative way to quantify broad differences in animal diets. By obtaining samples of pet food from cat owners we predicted that we would have high power to identify cats feeding on wild birds or mammals, given that pet food is thought to have higher C isotope values, due to the pervasive use of corn and/or corn by-products as food ingredients, than native prey. We worked with citizen scientists to quantify the isotopes of 202 cat hair samples and 239 pet food samples from the US and UK. We also characterized the isotopes of 11 likely native prey species from the southeastern US and used mixing models to assess the diet of 47 cats from the same region. Variation in C and N isotope values for cat food was very high, even within the same brand/flavor, suggesting that pet food manufacturers use a wide range of ingredients, and that these may change over time. Cat food and cat hair from the UK had lower C values than the US, presumably reflecting differences in the amount of corn used in the food chains of the two countries. This high variation in pet food reduced our ability to classify cats as hunters of native prey, such that only 43% of the animals could be confidently assigned. If feral or free ranging cats were considered, this uncertainty would be even higher as pet food types would be unknown. Our results question the general assumption that anthropogenic foods always have high C isotope values, because of the high variability we documented within one product type (cat food) and between countries (US vs. UK), and emphasize the need to test a variety of standards before making conclusions from isotope ecology studies.
CD86+/CD206+ tumor-associated macrophages predict prognosis of patients with intrahepatic cholangiocarcinoma
Authors: Sun Dalong , Luo Tiancheng , Dong Pingping , Zhang Ningping , Chen Jing , Zhang Shuncai , Liu Longzi , Dong Ling , Zhang Si
Published: January 2020

Background

As the main cellular ingredients of tumor microenvironment, tumor-associated macrophages (TAMs) play a vital role in tumor development and progression. Recent studies have suggested that TAMs are sensitive and specific prognostic factors in numerous cancers. The primary purpose of this study is to determine the prognostic significance of TAMs in intrahepatic cholangiocarcinoma (ICC).

Methods

Immunohistochemical staining of CD68, CD86 and CD206 were performed in tissue microarrays containing 322 patients, who underwent surgical resection and were pathologically diagnosed with ICC. The prognostic value of CD68, CD86 and CD206 were evaluated by Kaplan–Meier analysis (log-rank test) and nomogram models.

Results

We demonstrated that the CD86+/CD206+ TAMs model was an independent prognostic index for ICC patients. Patients with low CD86+ TAMs and high CD206+ TAMs infiltration had a markedly worse prognosis and increased risk of post-operative recurrence when compared to high CD86+ TAMs and low CD206+ TAMs intratumoral infiltration. Furthermore, subgroup analysis indicated that the CD86+/CD206+ TAMs model predicted prognosis of ICC patients more powerfully than single macrophage immunomarker. Interestingly, the CD86+/CD206+ TAMs model could further distinguish prognosis of CA-199 negative ICC patients, who were generally presumed to have a more favorable outcome. In order to further perfect the prognostic value of the CD86+/CD206+ TAMs model, we constructed and validated a postoperative nomogram to predict overall survival and recurrence-free survival time in ICC patients.

Conclusions

These findings indicate that the CD86+/CD206+ TAMs model possess potential value as a novel prognostic indicator for ICC patients.
Comparative Study of the Nutritive and Bioactive Compounds of Three Cucurbit Species Grown in Two Regions of Côte d’Ivoire
Authors: Diby N’Nan A. S. , Assoi Sylvie , Konan N’Guessan Y. , Coulibaly Adama , Biego Godi H. M.
Published: January 2020

Aims: The objective of this work was to contribute to the valorization of 3 local cucurbit oilseeds species grown in 2 producing regions of Côte d’Ivoire, namely the Kabadougou and the Moronou. Thus, a comparative study on the main nutritive and bioactive compounds of these cucurbits was conducted.

Methodology: Mature dried seeds of Citrullus lanatus sp, Lagenaria siceraria Molina Standl, and Cucumeropsis mannii Naudin, locally named respectively Wlewle, Bebou and Nviele, were collected in the 2 regions, dehulled and processed for analyses. Standard procedures of AOAC, AFNOR and FAO were used for the determination of the nutritive and bioactive compounds.

Results: Wlewle species exhibited the highest content of lipids (51.07±1.32%), energy caloric value (584.05±4.13 kcal/), polyphenols (141±23.97) and flavonoids (0.19±0.02) content. Nviele species had the highest protein (38.90±0.93%) and reducing sugar (70.62±1.03 mg/100 g) content. Bebou species exhibited the highest ash content (3.91±0.38%) and total soluble sugars (3.42±0.19%). Flavonoids content was similar for each species regardless of the region. Pearson’s correlation analysis revealed (p< 0.01) that energy caloric and lipid were directly correlated but conversely with protein. Direct correlation was also observed between polyphenols and lipid content in Wlewle and Nviele varieties, while in the Bebou, this trend was observed with protein. Despite their small shape, Wlewle species provide higher caloric energy upon consumption.
Perception of Students and Teachers towards Reforms on Agricultural Education Teaching and Learning
Authors: Biswas Nupur , Ghadei Kalyan , Biswas Nirupam
Published: January 2020

This paper is based on the study titled ‘Perception of Agriculture students and teachers towards reforms on agricultural education. The study was conducted at Banaras Hindu University in the Department of Extension Education, Institute of Agricultural Sciences. In this paper, the perception of teachers and students towards agricultural education has been studied. A sum of 775 students and teachers were considered which included 356 students of M. Sc. (Ag.), 292 Ph.D. scholars and 127 teachers from the Institute of Agricultural Sciences, BHU. 20 per cent from each category of population were selected randomly making the sample size of 156 as the respondents. The data was collected by the survey method. Both students and teachers (100 per cent) agreed that information related to higher education abroad to be provided in India to keep our education system aware of the developments abroad. It was found that 100 per cent of teachers in comparison to students (97.67 per cent) agreed that teachers should listen to their students with an open mind. Other findings are promotion of quality research and culture among students should be encouraged, learners should be aware towards farmers and their situation by farm visits, avoidance of spoon-feeding of teaching is necessary and many more. The study reveals more interesting reforms for agricultural education described in this original research article.
A Comparative Study on Antioxidation and Antibacterial Activities Triphala Herb Extracts from Chae Son, Lampang, Thailand
Authors: Pompimon Wilart , Baison Wipanoot , Chuajedton Angkhana , Udomputtimekakul Phansuang , Sombutsiri Punchavee , Wingwon Boonthawan , Udomtanakunchai Chatchanok
Published: January 2020

Introduction: Triphala, a herbal medicine which is a product from Chae Son, Lampang, Thailand, is an unequal-proportional mixture of fruits of three herbs, Phyllanthus emblica, Terminalia chebula, and Terminalia bellirica (2:1:1).

Materials and Methods: The contemporary study concentrated on extracts detection and comparative analysis between various annual year (A.D.2017/2018) activities in hexane, ethyl acetate, and methanolic extracts of Triphala. The determination of antioxidant was using by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). The broth dilution and agar well diffusion assay were determined antibacterial.

Results: Results exposed the valuable biological activity extracts from ethyl acetate and methanol solvents of T. chebula and T. bellirica, which strength is accountable for biological activities. Extracts displayed acceptable radical-scavenging activity analogous with ascorbic acid. The methanol extract of T. bellirica (0.0013 mg/mL), ethyl acetate extract of P. emblica (0.0009 mg/mL), in A.D. 2017 and the ethyl acetate extract of P. emblica (0.0090 mg/mL), the methanol extract of Triphala (0.0176 mg/mL) in 2018, were exhibited higher antioxidant activity. Also, extracts indicated hopeful antibacterial potential against tested strain comparable to chloramphenicol.

Conclusion: The results in A.D. 2017 showed that inhibition zone of P. emblica in ethyl acetate extract; S. aureas (8.67 mm), E. aerogenes (8.67 mm), E. coli (EPEC) (7.67 mm), P. mirabilis (7.73 mm) , S. typhimurium (8.33 mm), S. flexneri (8.33 mm) and V. cholera (7.33 mm) together with P. emblica methanol extract; S. aureas (6.67 mm), E. aerogenes (7.76 mm.)  and V. cholera (4.0 mm). Therefore, it could be concluded that Triphala may be a talented candidate in pharmaceutical and future medicine.
High‐Viscosity Copper Paste Patterning and Application to Thin‐Film Transistors Using Electrohydrodynamic Jet Printing
Authors: Can Thi Thu Thuy , Nguyen Tuan Canh , Choi Woon-Seop
Published: January 2020

Direct patterning of copper (Cu) electrodes through a noncontact electrohydrodynamic (EHD) jet printing process is developed to overcome the drawback of printing mechanisms such as high viscosity in inkjet printing. Printed Cu lines with a width of about 40 μm are obtained from Cu paste with a viscosity of 4000 cPs using an additive. The effect of the operating parameters on jetting modes and printed patterns is investigated. The electrical property of the printed Cu layer shows a low resistivity of 8 × 10−4 Ωm after sintering under vacuum compared with air annealing. Solution‐processed zinc tin oxide (ZTO) thin‐film transistors (TFTs) with vacuum‐annealed Cu source and drain (S/D) electrodes are fabricated with comparable characteristics, such as an average effective mobility in the saturation region (μ) of 0.50 cm2 V−1 s−1, an on‐to‐off current ratio (Ion/Ioff) of 5.5 × 105, and a subthreshold slope (SS) of 3.35 V decade−1. These results demonstrate the potential of EHD jet‐printed Cu for application in electronic devices.
Fabrication of Oxygen‐Vacancy Abundant NiMn‐Layered Double Hydroxides for Ultrahigh Capacity Supercapacitors
Authors: Tang Yanqun , Shen Haoming , Cheng Jinqian , Liang Zibin , Qu Chong , Tabassum Hassina , Zou Ruqiang
Published: January 2020

The rational design of advanced structures consisting of multiple components with excellent electrochemical capacitive properties is one of the crucial hindrances to be overcome for high‐performance supercapacitors (SCs). Herein, a superfast and facile synthesis of flower‐like NiMn‐layered double hydroxides (NiMn‐LDH) with high SC performance using an electrodeposition process on nickel foam is proposed. Oxygen vacancies are then modulated via mild H2O2 treatment for the first time, significantly promoting the electrochemical energy storage performance. The oxygen‐vacancy abundant NiMn‐LDH (Ov‐LDH) reaches a maximum specific capacity of 1183 C g−1 at the current density of 1 A g−1 and retains a high capacity retention of 835 C g−1 even at a current density of up to 10 A g−1. Furthermore, the assembled asymmetric SC device achieves a high specific energy density of 46.7 Wh kg−1 at a power density of 1.7 kW kg−1. Oxygen vacancies are proven to play a vital role in the improvement of electrochemistry performance of LDH based on experimental and theoretical studies. This vacancy engineering strategy provides a new insight into SC active materials and should be beneficial for the design of the next generation of energy storage devices.
Enhanced Performance of Perovskite Solar Cells via Low‐Temperature‐Processed Mesoporous SnO2
Authors: Wang Qiyun , Peng Changtao , Du Lin , Li Haijin , Zhang Wenfeng , Xie Jiale , Qi Hongchang , Li Yuepeng , Tian Liuwen , Huang Yuelong
Published: January 2020

Perovskite solar cells (PSCs) based on planar SnO2 (p‐SnO2) demonstrate excellent performance due to the superior properties of SnO2 as electron transporting layer (ETL). However, at present mesoporous SnO2 (m‐SnO2) still lags behind p‐SnO2 due to problems in the fabrication process of m‐SnO2. In this paper, a new strategy for preparing m‐SnO2 ETL is introduced which owns two valuable features: First, it applies a low temperature process to make mesoporous structure, which favors preserving the pristine properties of the raw SnO2 nanocrystals. Second, the degree of porosity and roughness of the m‐SnO2 layer can be well controlled, making it friendly to the following deposition process of PSCs. The performance of the PSCs based on the m‐SnO2 ETL prepared from this strategy shows an obvious improvement which is mainly from the improvement in Jsc and FF, suggesting a higher carrier collection efficiency for the m‐SnO2 ETL. The relevant characterizations including PL, TRPL, EIS, and KPFM confirm that the m‐SnO2 ETL possesses stronger electron extraction capability than the p‐SnO2 ETL. Hence, the proposed strategy can manifest the advantages of m‐SnO2 ETL meanwhile refrain its negative impacts, and thus promote the progress of the m‐SnO2 ETL‐based PSCs.
On the Physical Origins of Charge Separation at Donor–Acceptor Interfaces in Organic Solar Cells: Energy Bending versus Energy Disorder
Authors: de Sousa Leonardo Evaristo , Coropceanu Veaceslav , da Silva Filho Demétrio Antônio , Sini Gjergji
Published: January 2020

Charge separation (CS) is a central process in the working of organic solar cells (OSC). Despite the strong electron–hole (e–h) Coulombic attraction at the donor–acceptor (D–A) interface, the bound e–h pairs do separate into free charges following an ultrafast process. To explain these results, several models have been proposed. By means of kinetic Monte Carlo simulations, the energy bending (EB) at the D–A interface is considered as the driving force for CS against the impact of energy disorder. The results suggest that, while entropy and energy disorder alone allow for the bound e–h pairs to escape charger recombination, the efficiency of CS increases by several times and its timescale decreases significantly in the presence of EB, approaching experimental findings. The impact of external electric fields on CS efficiency is found to stem from insufficient amount of EB. Importantly, the results indicate that, in the absence of EB, simply improving charge carrier mobility in bulk has no effect on the performances of OSC, thus orienting the new materials design strategy toward preferably targeting interfacial properties. Guidelines regarding how to introduce EB at the D–A interface are also discussed.
Machine Learning for Soft Robotic Sensing and Control
Authors: Chin Keene , Hellebrekers Tess , Majidi Carmel
Published: January 2020

Herein, the progress of machine learning methods in the field of soft robotics, specifically in the applications of sensing and control, is outlined. Data‐driven methods such as machine learning are especially suited to systems with governing functions that are unknown, impractical or impossible to represent analytically, or computationally intractable to integrate into real‐world solutions. Function approximation with careful formulation of the machine learning architecture enables the encoding of dynamic behavior and nonlinearities, with the added potential to address hysteresis and nonstationary behavior. Supervised learning and reinforcement learning in simulation and on a wide variety of physical robotic systems have shown promising results for the use of empirical data‐driven methods as a solution to contemporary soft robotics problems.
A General and Practical Synthesis of Chiral 1,2‐Oxazetidines
Authors: Yang Jinggang , Wu Binyu , Hu Lin
Published: January 2020

1,2‐Oxazetidines are valuable small strained molecules that could be used to create new and conventionally difficult‐to‐access chemical transformations. Currently, asymmetric methods towards this class of heterocycles are very rare. Herein, we report a general and practical method to access a series of structurally diverse chiral 1,2‐oxazetidines from readily available chiral epoxides and α‐bromo esters in 3–4 steps by using mild Mitsunobu reactions as an efficient ring‐closure approach to form the highly strained four‐membered rings. The new method is operationally simple, and a range of N‐nosyl‐protected 3‐ and 4‐substituted as well as 3,4‐disubstituted chiral 1,2‐oxazetidines could be conveniently prepared in gram‐scale with excellent enantioselectivities (93–99% ee) and good overall yields for the first time.
Metal–Organic Frameworks for the Exploitation of Distance between Active Sites in Efficient Photocatalysis
Authors: Gong Xuan , Shu Yufei , Jiang Zhuo , Lu Lingxiang , Xu Xiaohui , Wang Chao , Deng Hexiang
Published: January 2020

Discoveries of the accurate spatial arrangement of active sites in biological systems and cooperation between them for high catalytic efficiency are two major events in biology. However, precise tuning of these aspects is largely missing in the design of artificial catalysts. Here, a series of metal–organic frameworks (MOFs) were used, not only to overcome the limit of distance between active sites in bio‐systems, but also to unveil the critical role of this distance for efficient catalysis. A linear correlation was established between photocatalytic activity and the reciprocal of inter active‐site distance; a smaller distance led to higher activity. Vacancies created at selected crystallographic positions of MOFs promoted their photocatalytic efficiency. MOF‐525‐J33 with 15.6 Å inter active‐site distance and 33 % vacancies exhibited unprecedented high turnover frequency of 29.5 h−1 in visible‐light‐driven acceptorless dehydrogenation of tetrahydroquinoline at room temperature.
Enantioselective Total Synthesis of Macfarlandin C, a Spongian Diterpenoid Harboring a Concave‐Substituted cis‐Dioxabicyclo[3.3.0]octanone Fragment
Authors: Allred Tyler K. , Dieskau André P. , Zhao Peng , Lackner Gregory L. , Overman Larry E.
Published: January 2020

The enantioselective total synthesis of the rearranged spongian diterpenoid (−)‐macfarlandin C is reported. This is the first synthesis of a rearranged spongian diterpenoid in which the bulky hydrocarbon fragment is joined via a quaternary carbon to the highly hindered concave face of the cis‐2,8‐dioxabicyclo[3.3.0]octan‐3‐one moiety. The strategy involves a late‐stage fragment coupling between a tertiary carbon radical and an electrophilic butenolide resulting in the stereoselective formation of vicinal quaternary and tertiary stereocenters. A stereoselective Mukaiyama hydration that orients a pendant carboxymethyl side chain cis to the bulky octahydronapthalene substituent was pivotal in fashioning the challenging concave‐substituted cis‐dioxabicyclo[3.3.0]octanone fragment.
Intracellular Electrochemical Nanomeasurements Reveal that Exocytosis of Molecules at Living Neurons is Subquantal and Complex
Authors: Larsson Anna , Majdi Soodabeh , Oleinick Alexander , Svir Irina , Dunevall Johan , Amatore Christian , Ewing Andrew G.
Published: January 2020

Since the early work of Bernard Katz, the process of cellular chemical communication through exocytosis, quantal release, has been considered to be all or none. Recent evidence has shown exocytosis to be partial or “subquantal” at single‐cell model systems, but there is a need to understand this at communicating nerve cells. Partial release allows nerve cells to control the signal at the site of release during individual events, for which the smaller the fraction released, the greater the range of regulation. Herein, we show that the fraction of the vesicular octopamine content released from a living Drosophila larval neuromuscular neuron is very small. The percentage of released molecules was found to be only 4.5 % for simple events and 10.7 % for complex (i.e., oscillating or flickering) events. This large content, combined with partial release controlled by fluctuations of the fusion pore, offers presynaptic plasticity that can be widely regulated.
Asymmetric Three‐Component Heck Arylation/Amination of Nonconjugated Cyclodienes
Authors: Zhu Daoyong , Jiao Zhiwei , Chi Yonggui Robin , Gonçalves Théo P. , Huang Kuo‐Wei , Zhou Jianrong Steve
Published: January 2020

Substituted cyclohexylamines are becoming increasingly important in drug discovery. Asymmetric Heck insertion/amination of nonconjugated cyclodienes proceeds to give 5‐aryl cyclohexenylamines with good enantioselectivity and exclusive trans configurations. Primary and secondary anilines, indoline, and benzylamines are suitable amines. The weakly donating diphosphite Kelliphite forms a deep unsymmetrical pocket, which is essential for stereoselective anti attack of amines.
Unveiling the Activity Origin of a Copper‐based Electrocatalyst for Selective Nitrate Reduction to Ammonia
Authors: Wang Yuting , Zhou Wei , Jia Ranran , Yu Yifu , Zhang Bin
Published: January 2020

Unveiling the active phase of catalytic materials under reaction conditions is important for the construction of efficient electrocatalysts for selective nitrate reduction to ammonia. The origin of the prominent activity enhancement for CuO (Faradaic efficiency: 95.8 %, Selectivity: 81.2 %) toward selective nitrate electroreduction to ammonia was probed. 15N isotope labeling experiments showed that ammonia originated from nitrate reduction. 1H NMR spectroscopy and colorimetric methods were performed to quantify ammonia. In situ Raman and ex situ experiments revealed that CuO was electrochemically converted into Cu/Cu2O, which serves as an active phase. The combined results of online differential electrochemical mass spectrometry (DEMS) and DFT calculations demonstrated that the electron transfer from Cu2O to Cu at the interface could facilitate the formation of *NOH intermediate and suppress the hydrogen evolution reaction, leading to high selectivity and Faradaic efficiency.
Synthesis and characterization of dimeric μ‐oxidovanadium complexes as the functional model of vanadium bromoperoxidase
Authors: Maurya Abhishek , Mahato Arun Kumar , Chaudhary Nikita , Kesharwani Neha , Kachhap Payal , Mishra Vivek Kumar , Haldar Chanchal
Published: January 2020

Two vanadium (IV) complexes [VIVO(Haeae‐sal)(MeOH)]+ (1) and [VIVO(Haeae‐hyap)(MeOH)]+ (2) were prepared by reacting [VO(acac)2] with ligands [H2aeae‐sal] (I) and [H2aeae‐hyap] (II) respectively. Condensation of 2‐(2‐aminoethylamino)ethanol with salicylaldehyde and 2‐hydroxyacetophenone produces the ligands (I) and (II) respectively. Both vanadium complexes 1 and 2 are sensitive towards aerial oxygen in solution and rapidly convert into vanadium(V) dioxido species. Vanadium(V) dioxido species crystalizes as the dimeric form in the solid‐state. Single‐crystal XRD analysis suggests octahedral geometry around each vanadium center in the solid‐state. To access the benefits of heterogeneous catalysis, vanadium(V) dioxido complexes were anchored into the polymeric chain of chloromethylated polystyrene. All the synthesized neat and supported vanadium complexes have been studied by a number of techniques to confirm their structural and functional properties. Bromoperoxidase activity of the synthesized vanadium(V) dioxido complexes 3 and 4 was examined by carrying out oxidative bromination of salicylaldehyde and oxidation of thioanisole. In the presence of hydrogen peroxide, 3 shows 94.4% conversion (TOF value of 2.739 × 102 h−1) and 4 exhibits 79.0% conversion (TOF value of 2.403 × 102 h−1) for the oxidative bromination of salicylaldehyde where 5‐bromosalicylaldehyde appears as the major product. Catalysts 3 and 4 also efficiently catalyze the oxidation of thioanisole in the presence of hydrogen peroxide where sulfoxide is observed as the major product. Covalent attachment of neat catalysts 3 and 4 into the polymer chain enhances substrate conversion (%) and their catalytic efficiency increases many folds, both in the oxidative bromination and oxidation of thioether. Polymer supported catalysts 5 displayed 98.8% conversion with a TOF value of 1.127 × 104 h−1 whereas catalyst 6 showed 95.7% conversion with a TOF value of 4.675 × 103 h−1 for the oxidative bromination of salicylaldehyde. These TOF values are the highest among the supported vanadium catalysts available in the literature for the oxidative bromination of salicylaldehyde.
Thermal Degradation of p‐Hydroxybenzoic Acid in Macadamia Nut Oil, Olive Oil, and Corn Oil
Authors: Castada Hardy Z. , Sun Zhaoyu , Barringer Sheryl A. , Huang Xuesong
Published: January 2020

p‐Hydroxybenzoic acid (PHBA) plays a significant role in sustaining the oxidative stability of macadamia nut oil (MNO). However, PHBA undergoes thermal decarboxylation and loses its bioactive antioxidant properties. In this study, we determine PHBA degradation kinetics in oils at various heating temperatures, which provides fundamental understanding of PHBA thermal degradation in oils and oil quality changes during high‐temperature processing. PHBA degradation kinetics in MNO, olive oil, and corn oil were evaluated at temperatures typical for cooking and frying. PBHA headspace concentration was measured using selected ion flow tube mass spectrometry. PHBA decarboxylation followed a zero‐order reaction, where degradation could be affected by factors such as the type of oil matrix having different FA compositions, antioxidants, and component interactions. PHBA degradation activation energies (E
a) showed that PHBA was more stable against thermal decarboxylation in MNO (85 kJ mol–1) than in olive oil (40 kJ mol−1) or corn oil (22 kJ mol−1). The higher enthalpy () of decarboxylation in MNO (82 kJ mol−1) indicates that PHBA is more inhibited from decomposition than olive oil (37 kJ mol−1) or corn oil (19 kJ mol−1). Moreover, the negative entropy values () of PHBA degradation from MNO (−192 J mol−1 K−1), olive oil (−277 J mol−1 K−1), and corn oil (−325 J mol−1 K−1) indicates that these oils impart some inhibitory properties against PHBA thermal decarboxylation.
Zeolite imidazolate framework (ZIF)‐based mixed matrix membranes for CO2 separation: A review
Authors: Guan Weixin , Dai Yan , Dong Chenyuan , Yang Xiaochen , Xi Yuan
Published: January 2020

Mixed matrix membranes (MMMs), which combine the good separation performance of inorganic materials with the low cost of polymers, have emerged as a research hotspot for gas separation membranes. Zeolite imidazolate frameworks (ZIFs) are widely used as fillers to prepare MMMs owing to their advantageous characteristics, such as adjustable pore channels, unsaturated sites, and easy functionalization. For MMMs, three directions can be employed as criteria for improvement compared with pristine polymeric membranes. In this article, the progress of ZIF‐based MMMs is reviewed from the aspects of sole‐ZIF‐based MMMs and modified ZIF‐based MMMs. Both strategies improve the separation performance through different improvement directions and mechanisms. Our analysis shows that the synergistic effect of the modified filler can change the structure of the membranes, such as by improving the filler–polymer interface voids, which provides a foundation to overcome the trade‐off effect to a certain extent. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48968.
Influence of pre‐electrophoresis on protein separations in polyacrylamide gels
Authors: Haris Anfal , Sanders Jonathan R. , Arce Pedro E.
Published: January 2020

Polyacrylamide gel electrophoresis (PAGE) is a widely used technique in protein separations. In this study, the effects of pre‐electrophoresis (i.e., exposing polyacrylamide gels to an electrical field prior to loading samples) on the separation of a mixture of 10 standard proteins was investigated. Three different gel concentrations (based on amounts of acrylamide and bis‐acrylamide, always at a 37.5:1 ratio) relative to the volume of the gel solution were tested: 6%, 9%, and 12%. For each concentration, multiple slab gels were subjected to pre‐electrophoresis prior to separation of proteins, while multiple other (i.e., companion) slab gels were used but without applying the pre‐electrophoresis technique. Separation results were investigated, showing that the application of the pre‐electrophoresis technique had a significant effect on separations particularly for 6% and 9% gels.
Optimization of dosing and mixing time through fabrication of high internal phase emulsion (HIPE) polymerization based adsorbents for use in purification of oil in water contaminated wastewater
Authors: Soliman Ahmed G. , El Naggar Ahmed M.A. , El‐Din Mahmoud R. Noor , Ramadan Ahmed M. , Youssef Mohamed A.
Published: January 2020

Disposal of oil‐contaminated wastewater is associated with serious environmental problems since it is drained in seawater or into the ground. These routes of disposal can dangerously affect the lives of both humans and aqua creatures. Therefore, this research study introduces the recovery of petroleum wastewater through the usage of polystyrene‐based adsorbents. High internal phase emulsion polymerization was the used methodology to provide the introduced structures where new approaches have been presented. Unlike the common, the influence of the fabrication parameters of polymeric adsorbents on the oil removal has been investigated. Particularly, different dosing and mixing times were utilized during the preparation stage. Their effect on the polymers surface properties and molecular weights were traced. The obtained adsorbents were subjected to the oil removal stage where optimization of synthesis conditions was taken place. Nearly 92% of the oil content (80 ppm) in the wastewater was removed using the optimized adsorbent. This adsorbent showed surface area of 28.8 m2/g and molecular weight equal 279,970 g/mol. It was acquired by applying 20 min as a dosing time and reaction time of 120 min.
Synthesis, in‐vitro and in‐silico study of novel thiazoles as potent antibacterial agents and MurB inhibitors
Authors: Sanad Sherif M. H. , Ahmed Ahmed A. M. , Mekky Ahmed E. M.
Published: January 2020

Efficient procedures are herein reported for the synthesis of novel hybrid thiazoles via a one‐pot three‐component protocol. The protocol involves the reaction of novel aldehyde, thiosemicarbazide and halogen‐containing reagents in solvent‐ and catalyst‐free conditions. The structures of the new thiazoles were elucidated by elemental analyses and spectroscopic data. The in‐vitro antibacterial screening and MurB enzyme inhibition assays were performed for the novel thiazoles. The thiazol‐4(5H)‐one derivative 6d, with p‐MeO, exhibits the best antibacterial activities with minimum inhibitory concentration values of 3.9, 3.9, 7.8, and 15.6 μg/ml against Staphylococcus aureus, Klebsiella pneumoniae, Streptococcus mutans, and Escherichia coli, respectively, as compared to the reference antibiotic drugs. It also exhibits the highest inhibition of the MurB enzyme with an IC50 of 8.1 μM. The structure–activity relationship was studied to determine the effect of the structures of the newly prepared molecules on the strength of the antibacterial activities. Molecular docking was also performed to predict the binding modes of the new thiazoles in the active sites of the E. coli MurB enzyme.
Female librarians and male computer programmers? Gender bias in occupational images on digital media platforms
Authors: Singh Vivek K. , Chayko Mary , Inamdar Raj , Floegel Diana
Published: January 2020

Media platforms, technological systems, and search engines act as conduits and gatekeepers for all kinds of information. They often influence, reflect, and reinforce gender stereotypes, including those that represent occupations. This study examines the prevalence of gender stereotypes on digital media platforms and considers how human efforts to create and curate messages directly may impact these stereotypes. While gender stereotyping in social media and algorithms has received some examination in the recent literature, its prevalence in different types of platforms (for example, wiki vs. news vs. social network) and under differing conditions (for example, degrees of human‐ and machine‐led content creation and curation) has yet to be studied. This research explores the extent to which stereotypes of certain strongly gendered professions (librarian, nurse, computer programmer, civil engineer) persist and may vary across digital platforms (Twitter, the New York Times online, Wikipedia, and Shutterstock). The results suggest that gender stereotypes are most likely to be challenged when human beings act directly to create and curate content in digital platforms, and that highly algorithmic approaches for curation showed little inclination towards breaking stereotypes. Implications for the more inclusive design and use of digital media platforms, particularly with regard to mediated occupational messaging, are discussed.
Multilingual publishing in the social sciences and humanities: A seven‐country European study
Authors: Kulczycki Emanuel , Guns Raf , Pölönen Janne , Engels Tim C. E. , Rozkosz Ewa A. , Zuccala Alesia A. , Bruun Kasper , Eskola Olli , Starčič Andreja Istenič , Petr Michal , Sivertsen Gunnar
Published: January 2020

We investigate the state of multilingualism across the social sciences and humanities (SSH) using a comprehensive data set of research outputs from seven European countries (Czech Republic, Denmark, Finland, Flanders [Belgium], Norway, Poland, and Slovenia). Although English tends to be the dominant language of science, SSH researchers often produce culturally and societally relevant work in their local languages. We collected and analyzed a set of 164,218 peer‐reviewed journal articles (produced by 51,063 researchers from 2013 to 2015) and found that multilingualism is prevalent despite geographical location and field. Among the researchers who published at least three journal articles during this time period, over one‐third from the various countries had written their work in at least two languages. The highest share of researchers who published in only one language were from Flanders (80.9%), whereas the lowest shares were from Slovenia (57.2%) and Poland (59.3%). Our findings show that multilingual publishing is an ongoing practice in many SSH research fields regardless of geographical location, political situation, and/or historical heritage. Here we argue that research is international, but multilingual publishing keeps locally relevant research alive with the added potential for creating impact.
High Energy Li‐Ion Electrodes Prepared via a Solventless Melt Process
Authors: Astafyeva Ksenia , Dousset Capucine , Bureau Yannick , Stalmach Sara‐Lyne , Dufour Bruno
Published: January 2020

High areal density and high energy Li‐ion electrodes were prepared using a high throughput green, solventless and inexpensive melt process leading to electrodes of controlled porosity. Melt formulations were developed for NCA cathodes and graphite anodes. The formulations were based on commercially available and inexpensive elastomeric or thermoplastic binders, conventional conducting fillers and >90 wt% electrode active materials. A large range of loadings could be achieved, from 4 to 40 mg cm−2 single side. Electrochemical performances in half cells (coin cells) are reported. High capacity and cyclability for high loadings of NCA cathodes and graphite anodes were demonstrated. Areal capacities over 5 mAh.cm−2 in coin cells were obtained at a C/5 rate. Cycling at high rates, up to 5 C was demonstrated.
Ric‐8A, a GEF, and a Chaperone for G Protein α‐Subunits: Evidence for the Two‐Faced Interface
Authors: Srivastava Dhiraj , Artemyev Nikolai O.
Published: January 2020

Resistance to inhibitors of cholinesterase 8A (Ric‐8A) is a prominent non‐receptor GEF and a chaperone of G protein α‐subunits (Gα). Recent studies shed light on the structure of Ric‐8A, providing insights into the mechanisms underlying its interaction with Gα. Ric‐8A is composed of a core armadillo‐like domain and a flexible C‐terminal tail. Interaction of a conserved concave surface of its core domain with the Gα C‐terminus appears to mediate formation of the initial Ric‐8A/GαGDP intermediate, followed by the formation of a stable nucleotide‐free complex. The latter event involves a large‐scale dislocation of the Gα α5‐helix that produces an extensive primary interface and disrupts the nucleotide‐binding site of Gα. The distal portion of the C‐terminal tail of Ric‐8A forms a smaller secondary interface, which ostensibly binds the switch II region of Gα, facilitating binding of GTP. The two‐site Gα interface of Ric‐8A is distinct from that of GPCRs, and might have evolved to support the chaperone function of Ric‐8A.
Endothelium capture-based liver segment imaging using vascular endothelial growth factor receptor 2 in preclinical ex vivo models
Authors: Kyuno D , Qian B , Groß W , Schäfer M , Ryschich E
Published: January 2020

Background

Near-infrared (NIR) imaging of liver segments provides substantial information for surgeons performing liver resection. It was hypothesized that ramucirumab, an endothelium-specific antibody approved by the Food and Drug Administration, could be used for liver segment imaging using the endothelium capture principle.

Methods

The capture efficacy of anti-vascular endothelial growth factor receptor (VEGFR) 2 monoclonal antibodies (mAbs) and segment imaging were studied in a mouse model. Binding of ramucirumab in human and porcine tissues was studied using immunofluorescence staining. Isolated porcine liver perfusion was used to analyse the labelling and NIR imaging of selected liver segments.

Results

VEGFR2 is well expressed on the endothelium of the smallest microvascular blood vessels in mouse, porcine and human liver tissues, as well as in human liver tumours. Perfusion of selected segments in the isolated liver model showed high capture of the anti-VEGFR2 (clone 522302) mAb and ramucirumab in mice and pigs respectively. NIR imaging of selected segments was achieved using isolated porcine liver perfusion with IRDye® 800CW-conjugated ramucirumab.

Conclusion

VEGFR2 is well expressed on the smallest microvascular blood vessels and can capture antibodies during single intravascular passages with high efficacy. The ex vivo imaging of a selected segment using endothelial capture of ramucirumab demonstrates the potential of this antibody for intraoperative navigation in liver surgery. Surgical relevanceImaging of liver segments provides substantial information for surgeons when performing liver resection.The antivascular endothelial growth factor receptor (VEGFR) 2 antibody ramucirumab conjugated with near-infrared dye could visualize selected liver segments using an endothelial capture-based approach in an isolated perfusion liver model.The ex vivo imaging of a selected segment using endothelial capture of ramucirumab demonstrates the potential of this anti-VEGFR2 antibody for intraoperative navigation in liver surgery.