bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of structural modifications on the drying kinetics of foods: changes in volume, surface area and product shape
Authors: De Michelis Antonio , Márquez Carlos A. , Mabellini Alejandra , Ohaco Elizabeth , Giner Sergio A.
Published: January 2020

Macro and micro-structural changes take place during food dehydration. Macro-structural changes encompass modifications in shape, area and volume. Studies of such changes are important because dehydration kinetics (essential for calculating industrial dryers) may be highly influenced by changes in food shape and dimensions. The overall changes in volume, surface area (“shrinkage”) and shape (Heywood factor, with provides a close description of food shape) were determined experimentally, and the results were correlated with simple expressions. Hence, although dehydration kinetics can be modeled with simplified overall shrinkage expressions, the possibility of selecting a suitable geometry and predicting the characteristics dimensions will provide higher accuracy. An additional unresolved problem is the lack of a general model that predicts macro-structural changes for various foods and diverse geometries. In this work, based on experimental data of sweet and sour cherries, and rose hip fruits, a simplified general model to predict changes in volume and surface area are proposed. To estimate how the changes in characteristic dimensions affect the kinetic studies, experimental drying curves for the three fruits by means of a diffusional model considered the following variants for the characteristic dimensions: (i) The radius of the fresh food, assumed constant; (ii) The radius of the partially dehydrated product; (iii) The radius predicted by the correlation for structural changes, especially volume, obtained in this work and generalized for the three fruits, and (iv) to demonstrate the need to study the macro-structural changes for all dehydrated foods, also be present the case of a restructured food.
The AgroParisTech “Social Openings” mission
Authors: Baroiller Annie , Dumoulin Elisabeth
Published: January 2020

Underprivileged secondary school and college students tend to demonstrate limited ambitions with regards to further education and acquiring superior qualifications. In a partnership with higher education schools, such as AgroParisTech, encounters have been organised between high school students and higher education students acting as volunteering mentors. The aim is to present the high school students with the opportunity to explore new opportunities as well as to provide them with information about high profile careers and higher level training through various activities led by the higher education students, as well as through meetings, visits, weekends organised around a specific theme. Examples of such initiatives  show what benefits both the high school and higher education students can derive from them.
Effect of drying techniques on the retention of antioxidant activities of Saskatoon berries
Authors: Mitra Pranabendu , Meda Venkatesh , Green Rick
Published: January 2020

The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P<0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P<0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P<0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P<0.05.
Dried Fruit Matrices Incorporated with a Probiotic Strain of Lactobacillus plantarum
Authors: Ribeiro Catarina , Freixo Ricardo , Silva Joana , Gibbs Paul , Morais Alcina , Teixeira Paula
Published: January 2020

The development of fruits and vegetables containing probiotics is a topic of great interest and popularity for health-conscious consumers. The aim of this study was to evaluate the possibility of using dried fruit matrices as delivery vehicles for probiotics. Different fruits — kiwi, mango, strawberry, pineapple, banana — were used as food matrices to test the viability of a strain of Lactobacillus plantarum, which was determined after drying at 40ºC and at different storage times. Cell survival after drying decreased by ca. 1 log in banana and strawberry, to 3 log, for kiwi. The bacterial numbers in banana and strawberry dried pieces at the time of storage at room temperature and 4ºC were approximately 107 cfu/g. After 37 days storage at room temperature, no viable counts were observed in any of the fruits studied. However, at 4ºC after this period of time, viable cells were detected for all the fruits (1.9x106 cfu/g, 1.5x105 cfu/g 1.5x105 cfu/g, 4.7x104 cfu/g 8.0x103 cfu/g, for strawberry, banana, kiwi, mango and pineapple, respectively).
Audiovisual translation of puns in animated films: strategies and procedures
Authors: Aleksandrova Elena
Published: January 2020

The translation of the pun is one of the most challenging issues for translators and interpreters. Sometimes puns, especially those containing realia, are considered to be untranslatable. Most translation strategies and procedures offered in previous findings for the translation of realia-based puns are not appropriate for audiovisual translations of animated films, for either dubbing or subtitling. It is caused by the specificity of the target audience, and the genre. The problem of choosing the most relevant strategy and procedures for realia-based puns is underexplored. To narrow the gap, the metamodern and semiotic approaches are applied to the translation of puns. In accordance with the semiotic approach, a pun is considered as a type of language game, based on the use of the asymmetry of the form, and the content of the sign. The “Quasi-translation” strategy offered in this paper reflects the attitude to the game in metamodernism, where the “game change” is one of the basic postulates. “Quasi-translation” involves three types of translation procedures: quasi-localisation, quasi-globalisation, and quasi-glocalisation. The term, “quasi-glocalisation”, is also used to denote the general strategy for the translation of audiovisual works containing realia-based puns, which involves: 1) oscillation between the need to adapt the translation to the target culture, and the need to preserve the culturally-marked components of the original; and 2) the reproduction of “atmosphere” (the common reality of the perceiver and the perceived). This insight can be used by audiovisual translator-practitioners, and university teachers in the course of translation theory and practice.
Conceptual blending in English and Serbian question-and-answer jokes: cultural transfer issues
Authors: Niketić Predrag
Published: January 2020

This paper analyzes English and Serbian question-and-answer jokes using the cognitive linguistic theoretical framework of conceptual blending, which relies on mental spaces as cognitive packets of information used to interpret the world around us and within us. The analysis is used to illustrate how culture influences humour, specifically how the Anglo-American culture, the dominant and best-known foreign culture in Serbia, is used as a basis of jokes in English as well as Serbian. It is shown that the jokes in English can work on a non-English-speaking Serbian recipient culturally, but only if not impeded by linguistic obstacles, such as untranslatable puns. The selected Serbian jokes illustrate intercultural merging, as they use elements from both Anglophone and Serbian pop-cultures to create humour that is difficult to transfer back to Anglophone audiences, but now due to linguistic as well as cultural transfer issues. These issues revolve around humour translation, which is made difficult by linguistic aspects, cultural aspects, or both. Conceptual blending and the mental spaces involved provide a useful tool for adapting cultural/linguistic barriers to obtain more or less workable joke translations.
Translating irony into Arabic – who’s having the last laugh? Dubbing Monsters Inc.: Egyptian vernacular vs. modern standard Arabic
Authors: Yahiaoui Rashid , Alqumboz Basema , Fattah Ashraf , Al Adwan Amer
Published: January 2020

Monsters Inc., an animated feature film produced by Pixar Animation Studios in 2001, received significant recognition worldwide. The film was nominated in 2002 for the ASCAP Film and Television Music Awards by the Box Office Films. Two dubbed versions of the film were later released with Arabic translations using Egyptian Vernacular, a spoken dialect, and Modern Standard Arabic, used primarily in formal, written communications.This study examines humor in translation and irony as humor which represents a common technique in “Pixar plotting”. The research investigates the strategies, types, and categories of irony as humor within the translations and the success of those translations at accurately transmitting the humorous meaning. Towards exploring the problems of translating irony across languages and cultures, this research examines the shifts in translations between the two Arabic language versions using an interdisciplinary theoretical approach encompassing humor studies, audiovisual translation studies, and descriptive translation studies. Furthermore, the research adopts Muecke’s (1978) classification of irony markers to categorize and identify the strategies used in translating irony as humor. The study finds that the two different versions of Arabic utilize similar strategies at times and divergent ones at others, such as explication, substitution, omission or addition, in translating irony as humor with each succeeding/failing at varied levels of meaning transmission. The research suggests translators’ creativity, or lack thereof, and the language variant used are primarily responsible for the success or failure of transmitting irony as humor for dubbing into Arabic.
Response of Maize (Zea mays) on Crude Oil Polluted Soil after One Month of Remediation with Spent Mushroom Substrate
Authors: Chukwumati J. A. , Ibanibo G. C. , Adedokun O. M.
Published: January 2020

The study was conducted to evaluate the influence of different levels of crude oil pollution remediated with spent mushroom substrate (SMS) on the growth of maize after one month of pollution. Composite soil samples randomly collected were polluted with Bonny light crude oil (v/w) at a concentration of 0%, 2%, 4% and 6% in a perforated plastic pots with 6 kg of top soil (0-20) cm.  Ten percent of decomposed SMS was applied on each of the pots. A month after remediation, four seeds of Oba Super 11 maize variety were sown into each pot and later thinned to two after germination. The design was Complete Randomized Design consisting of six treatments and four replicates. After eight weeks of the study, results revealed a reduction in plant germination rate (60%) in polluted (SCM) against (87%) in non-polluted (SM) soil. Plant germination was highest (93.8%) on natural soil (SSM) amended with SMS. Amendment of the polluted soil with SMS improved the germination of the plant from 60% to 75%. There was a significant (P<0.01) decrease in plant height on polluted against natural soils. Amendment of the polluted soil with SMS slightly increased the height of the plant though not significant within the first six weeks of the study, however, a significant (P<0.01) increase was observed on the seventh and eighth weeks of the study. Pollution of the soil with crude oil revealed significant (P<0.01) reduction on some soil physico-chemical properties (available phosphorus, exchangeable cations (Ca, Mg and K), while a significant (P<0.01) increase was observed on total hydrocarbon content, total nitrogen, total organic carbon and total organic matter on the polluted over natural soil. Amendment of the polluted soil with SMS improved the nutrient status of the soil as there was significant (P<0.01) increase in the concentration of Ca, Mg, K, P and a reduction in the content of THC, TOC of the soil. Remediation of crude oil polluted soil, with spent mushroom substrate a month after pollution, improved soil fertility.
Offline Handwritten Signature Recognition Based on SIFT and SURF Features Using SVMs
Authors: Sriwathsan W. , Ramanan M. , R. Weerasinghe A.
Published: January 2020

Biometric recognition for human identification plays a key role in the rapid development of computer vision and pattern recognition research areas. The biometrics, refers to the automatic identification of a person based behavioral characteristics, physiological properties or traits. Signature recognition is one such human identification method and can be performed either in offline or online mode. This paper proposed an offline handwritten signature recognition which is based on image processing technique, scale-invariant feature transform (SIFT) and speeded-up robust features (SURF) features and support vector machines (SVMs). The handwritten signature images were then recognized through the proposed method that involves identification of regions of interest and representation of those regions as SIFT or SURF, construction of codebooks and the multi-class classification of the feature histograms using support vector machines (SVMs). Experiments have been carried out with our dataset of 1600 samples and a recognition rate in excess of 95% was obtained over the ten-fold cross validations.
Chaos Based Image Encryption Scheme Using One Dimensional Exponential Logistic Map
Authors: Gbaden Terlumun , Nachaba Blama
Published: January 2020

The widespread use of images in various sectors of life makes its protection increasingly necessary and important. An improvement over encryption and decryption algorithm using exponential logistic chaotic map was proposed. In this work, we adopt an encryption/decryption strategy for colour images using the exponential logistic chaotic map. The proposed encryption/decryption algorithms are implemented in MATLAB for computer simulation. The experimental results indicate that the proposed algorithms can be used successfully to encrypt/decrypt images with secret keys. The performance analysis using histogram uniformity analysis and correlation coefficient show that the algorithms give larger space, quick speed and easy to realize. The encrypted images have good encryption effect and low correlation coefficient rendering it a good candidate for confidential and secure means of transmitting image information in untrusted networks.
Relationship between Dose and Duration of Administration of Potassium Bromate on Selected Electrolytes and Hepatorenal Parameters in Male Albino Wistar Rats
Authors: Y. Gazuwa Samuel , D. Dabak Jonathan , H. Jaryum Kiri , Oluwa Ige
Published: January 2020

Aim: To monitor the effects of dosage and duration of administering KBrO3 on some electrolytes and hepatorenal parameters in male albino Wistar rats.

Study Design: 24 rats, mean weight of 181.3 g were grouped into 4 with 6 rats of each. Experiment spanned over 12 days. In the control group, animals were fed standard diet. Animals in the test groups were fed diet containing 67, 100 and 167 mg/kg dose of KBrO3 according to body weight. 2 rats from each group were sacrificed on the 4th, 8th and 12th days.

Place and Duration of Study: University of Jos; 1 month including writing the report.

Methods: Spectrophotometric and titrimetric techniques were applied. InStat3 statistical software was used to analyse the data obtained. P≤.05 was considered significant.

Results: on the 4th day at 67mg/kg dose, showed raised serum activities (IU) of ALT, 41.0±9.6, and AST, 130.2±31.53, (P=.05). At 100 mg/kg dose, serum activities of ALT, 52.12±1.12, AST, 180.0±0.41, and level (g/L) of Total Proteins, TP, 67.77±0.35, were elevated (P=.05).On the 8th day at 67mg/kg dose, there were no significant increases (P>.05). At 100 mg/kg dose, only AST activity, 98.0±43.86, increased (P=.05). Levels of urea (UR) and creatinine (CR) were lower than the control at both 60 and 100 mg/kg dose. At 167mg/kg dose, level of TP and activities of ALT, and AST increased (P=.05) relative control. On the 12thday, treatments at 67 mg/kg dose raised the activities of ALT and AST (P=.05).At 100 mg/kg dose, level of creatinine, 106±19.2 µmol/L, was significantly (P=.05) elevated. For urea, mmol/L, test groups results (4.26±1.39; 6.70±2.01; 21.07±2.21) were higher (P=.05) relative control group. Activities of AST and ALP were raised (P=.05). On the 12th day at 167 mg/kg dose, TP, ALT, AST and ALP significantly (P=.05) elevated implying toxicity of KBrO3 is both dose and duration of exposure-depended. On 4th and 8th day of treatment, mean level of Cl- was significantly (P=.05) raised whereas HCO3- was not significantly (P>.05) increased. 12th day of experimentation resulted in dose, and duration of exposure dependent increase concentration of Cl- (P=.05).

Conclusion: This compound could potentially cause injury to, especially hepatocytes and nephrons. It can also perturb the redox status of the cell with its attendant metabolic consequences; hence, moderate use is imperative.
Bio-ethanol (2nd Generation Ethanol): A Solution to Ever Polluting Gasoline to Climate in India
Authors: Mohapatra Shruti , Kishore Mishra Raj , K. Sarangi Khitish
Published: January 2020

Environmentally sustainable energy sources are called for due to contemporaneous development in industries along with the rapid pace of urbanization. Ethanol produced from biomass can be deliberated as a clean and safest liquid fuel and an alternative to fossil fuels as they have provided unique environmental, strategic economic benefits. For the past decade, it has been noticed that there is an increasing trend found in bio ethanol production which has created a stimulus to go for advancement in bio ethanol production technologies. Several feed stocks have been used for the bio ethanol production but the second generation bio ethanol has concentrated on the lignocellulosic biomass. Plenteous lignocellulosic biomass in the world can be tapped for ethanol production, but it will require significant advances in the ethanol production process from lignocellulosic because of some technical and economic hurdles found in commercial scale. This review will encompass the current status of bio ethanol production in terms of their economic and environmental viability along with some research gaps as well as policy implications for the same.
Effect of Organic Mulching on Weed Suppression, Yield and Yield Components of Sesame (Sesamum indicum L.)
Authors: Teame Goitom
Published: January 2020

Sesame is the second in oil crop produced in Ethiopia next to Niger seed and it is also second foreign currency generator in the country. Weeds are the most significant problem in sesame producing areas. This research was conducted with the aim of reducing weed infestation and boost yield. The experiment was conducted in 2016 cropping season at Humera Agricultural Research Center in RCBD design. Growth performance, yield and yield components of sesame and weed data were collected. Less abundant and dense Rahynochosia malacophylla weeds (33) and (132/m2) were recorded at Sudan grass, where the most abundant and dense Rahynochosia malacophylla weeds (60.5) and (242/m2) were recorded from no-mulch plot. The highest sesame yield (695 kg ha-1) was recorded from Sudan grass treatment, while the lowest yield (225 kg ha-1) was recorded from no mulch. Farmers need to apply grass mulch to suppress weed growth and boost sesame yield.
The Effect of Ginger (Zingiber officinale) on Diet Induced Hyperlipidemia and Tissue Histology in Adult Female Wistar Rats: A Biochemical and Histopathological Study
Authors: Akanfe Olufunke R. , Komolafe Ibukunoluwa A. , Iyanda Ayobola A.
Published: January 2020

The study is aimed at determining the atheroprotective property of ginger (Zingiber officinale) aqueous extract to rats fed with a high-fat diet. Each group consisted of 5 rats. Group 1 represent the control group and received normal rat pellets; groups 2-5 were maintained on high-fat diet for 6 weeks to establish hyperlipidemia. Groups 1, 2, 3, 4 and 5 received distilled water, distilled water, 400, 500 and 600 mg/kg (body weight) Zingiber officinale respectively for 4 weeks. Serum concentrations of triglycerides (TG), total cholesterol (TC) and high-density lipoprotein-cholesterol (HDL-C) were determined using standard biochemical methods. Histologic examination of tissues was by Hematoxylin-Eosin staining technique. Data were analyzed using Student’s t-test and P<0.05 was considered significant. A decrease in the mean concentrations of TG, TC, low-density lipoprotein (LDL-C) and increase in HDL-C concentration of each of the treatment groups (3, 4, 5) were observed when compared with that of group 2. In rats fed high-fat diet, histologic abnormalities were observed for the heart, liver, and kidney which were not adequately corrected by ginger treatment. Results suggest that at dosage levels studied, aqueous ginger extract ameliorated biochemical but not histologic consequences of the high-fat diet.
The Standard Model vs. Physical Facts
Authors: Comay E.
Published: January 2020

Dynamical sectors of the Standard Model of particle physics are critically analyzed. It is proved thatquantum electrodynamics, quantum chromodynamics, and the electroweak theory are inconsistentwith fundamental physical principles. More than two examples apply to each of these theories, andany of these examples substantiate the unacceptable status of the relevant theory. Unfortunately,the mainstream particle physics literature ignores this situation and glorifies the Standard Modelas an excellent scientific theory.
Electrohydrodynamic Jet Printed 3D Metallic Grid: Toward High‐Performance Transparent Electrodes
Authors: Zhang Bin , Lee Hyungdong , Byun Doyoung
Published: January 2020

2D metallic grids that consist of various nanomaterials that are suitable for the replacement of indium tin oxide in transparent electronics (TEs) manufacturing. High‐resolution conductive grids with large open areas are often required while considering high transmittance. However, previous research shows that this kind of TE often cannot have high transmittance and low sheet resistance simultaneously; it hinders the fabrication techniques and materials from practical applications. Herein, direct fabrication of a high‐performance TE through electrohydrodynamic jet 3D printing technique is reported. Micro‐scale 3D metallic grids with an aspect ratio of above‐5 were printed on a polyester film using Ag nanoparticles. The metal grids with high aspect ratios exhibit an average sheet resistance of 3 Ω sq−1 and transparency of 96%. Both optical and electrical performances are significantly enhanced for which the large cross‐section of the metallic grid is contributed. Furthermore, the flexibility of printed TE is also characterized by the bending and recovering test. It is believed that the printed flexible TE, which utilize a high aspect ratio, 3D metallic grids may replace the conventional ITO glass for which both high transmittance and conductivity are achieved with economic efficiency.
Rapid Photocrosslinking of Silk Hydrogels with High Cell Density and Enhanced Shape Fidelity
Authors: Cui Xiaolin , Soliman Bram G. , Alcala‐Orozco Cesar R. , Li Jun , Vis Michelle A. M. , Santos Miguel , Wise Steven G. , Levato Riccardo , Malda Jos , Woodfield Tim B. F. , Rnjak‐Kovacina Jelena , Lim Khoon S.
Published: January 2020

Silk fibroin hydrogels crosslinked through di‐tyrosine bonds are clear, elastomeric constructs with immense potential in regenerative medicine applications. In this study, demonstrated is a new visible light‐mediated photoredox system for di‐tyrosine bond formation in silk fibroin that overcomes major limitations of current conventional enzymatic‐based crosslinking. This photomediated system rapidly crosslinks silk fibroin (<1 min), allowing encapsulation of cells at significantly higher cell densities (15 million cells mL−1) while retaining high cell viability (>80%). The photocrosslinked silk hydrogels present more stable mechanical properties which do not undergo spontaneous transition to stiff, β‐sheet‐rich networks typically seen for enzymatically crosslinked systems. These hydrogels also support long‐term culture of human articular chondrocytes, with excellent cartilage tissue formation. This system also facilitates the first demonstration of biofabrication of silk fibroin constructs in the absence of chemical modification of the protein structure or rheological additives. Cell‐laden constructs with complex, ordered, graduated architectures, and high resolution (40 µm) are fabricated using the photocrosslinking system, which cannot be achieved using the enzymatic crosslinking system. Taken together, this work demonstrates the immense potential of a new crosslinking approach for fabrication of elastomeric silk hydrogels with applications in biofabrication and tissue regeneration.
Supercharged Proteins and Polypeptides
Authors: Ma Chao , Malessa Anke , Boersma Arnold J. , Liu Kai , Herrmann Andreas
Published: January 2020

Electrostatic interactions play a vital role in nature. Biomacromolecules such as proteins are orchestrated by electrostatics, among other intermolecular forces, to assemble and organize biochemistry. Natural proteins with a high net charge exist in a folded state or are unstructured and can be an inspiration for scientists to artificially supercharge other protein entities. Recent findings show that supercharging proteins allows for control of their properties such as temperature resistance and catalytic activity. One elegant method to transfer the favorable properties of supercharged proteins to other proteins is the fabrication of fusions. Genetically engineered, supercharged unstructured polypeptides (SUPs) are just one promising fusion tool. SUPs can also be complexed with artificial entities to yield thermotropic and lyotropic liquid crystals and liquids. These architectures represent novel bulk materials that are sensitive to external stimuli. Interestingly, SUPs undergo fluid–fluid phase separation to form coacervates. These coacervates can even be directly generated in living cells or can be combined with dissipative fiber assemblies that induce life‐like features. Supercharged proteins and SUPs are developed into exciting classes of materials. Their synthesis, structures, and properties are summarized. Moreover, potential applications are highlighted and challenges are discussed.
Plant‐Inspired Soft Bistable Structures Based on Hygroscopic Electrospun Nanofibers
Authors: Lunni Dario , Cianchetti Matteo , Filippeschi Carlo , Sinibaldi Edoardo , Mazzolai Barbara
Published: January 2020

The tissue composition and microstructures of plants have dynamic morphologies that change according to their environments. Recently, multifunctional responsive materials and smart structures also took inspiration from these plants' features.Dionaea muscipulaleaves provide a remarkable example of an optimized structure that, owing to the synergistic integration of bistability, material, and geometrical properties, permits to overcome the performance limits of purely diffusive processes. In this paper, a hygroscopic bistable structure (HBS) inspired by the Venus flytrap leaves is presented, obtained by bonding prestretched poly(dimethylsiloxane) (PDMS) layers prior to depositing electrospun polyethylene oxide (PEO) nanofibers. A hygroresponsive bilayer (HBL) is also obtained by electrospinning of PEO on an unstretched PDMS layer. The hygroscopic material (Young's modulus and hygroscopic expansion) is mechanically characterized so as to predict the response time of a bending HBL in response to a step humidity variation. The HBS response time (≈1 s) is sensibly lower than the one of purely diffusive HBL (≈10 s) thanks to bistability. An illustrative implementation is also presented, exploiting an HBS to trigger the curvature of a PDMS optical focusing system. The developed plant‐inspired soft bistable structure can also be used for sensing (e.g., humidity), energy harvesting, as well as advanced soft robotics applications.
A Highly Accurate, Stretchable Touchpad for Robust, Linear, and Stable Tactile Feedback
Authors: Shao Ruomei , Wang Chunnan , Wang Guiqiang , Zhao Jingru , Sun Shuqing
Published: January 2020

A stretchable and steady performance of human–machine interfaces and localized tactile perception is a broad concerning problem. Existing tactile sensors and touchpads claim to be stretchable for location detection failing to offer a location with uniformity during inevitable flexible movements, as well as linearity. The fabrication of a highly stretchable and transparent touch sensor, which is made of hydrogels and PDMS, could simultaneously and precisely determine location and pressure while being stretched or unstretched. It is noteworthy that the sensor introduces a new structure of resistant‐system into stretchable sensors, which needs only four electrodes in 3D helical structure without sacrificing linearity. A few drops of silicone oil are added to the interfaces to prevent the dehydration of the hydrogels, which is a common problem leading to device failure. In the same time, the transparency is improved significantly from 84.3% to 96%. Its interface application is demonstrated by practically using it for drawing, dialing numbers, calculating, and playing cards. Finite element analysis based on Ogden models indicates that the sensor shows instant response without delay, which is vital for super‐elastic materials based electronics.
Application of Transaminases in a Disperse System for the Bioamination of Hydrophobic Substrates
Authors: Fiorati Andrea , Berglund Per , Humble Maria S. , Tessaro Davide
Published: January 2020

The challenging bioamination of hydrophobic substrates has been attained through the employment of a disperse system consisting of a combination of a low polarity solvent (e. g. isooctane or methyl‐tert‐butylether), a non‐ionic surfactant and a minimal amount of water. In these conditions, amine transaminases (ATA) were shown to efficiently carry out the reductive amination of variously substituted cyclohexanones, providing good conversions often coupled with a superior stereoselectivity if compared with the corresponding chemical reductive amination. An array of synthetically useful 4‐substituted aminocyclohexanes was consequentially synthesized through biocatalysis, analyzed and stereochemically characterized.

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Intermolecular Iodofluoroalkylation of Unactivated Alkynes and Alkenes Mediated by Manganese Catalysts
Authors: Ji Yun‐Xing , Wang Lu‐Jun , Guo Wei‐Si , Bi Qirui , Zhang Bo
Published: January 2020

An approach for iodofluoroalkylation of unactivated alkynes and alkenes facilitated by an earth‐abundant and inexpensive manganese catalyst, Mn2(CO)10, is reported. This protocol employs visible light as the energy input and shows a wide substrate scope and high functional‐group compatibility. A variety of synthetically useful fluoroalkylated alkyl and alkenyl iodides can be prepared in moderate to excellent yields. The reaction features high efficiency, operational simplicity, scalability, as well as excellent chemo‐, regio‐, and E/Z selectivities.

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Impact of Stacking Faults and Domain Boundaries on the Electronic Transport in Cubic Silicon Carbide Probed by Conductive Atomic Force Microscopy
Authors: Giannazzo Filippo , Greco Giuseppe , Di Franco Salvatore , Fiorenza Patrick , Deretzis Ioannis , La Magna Antonino , Bongiorno Corrado , Zimbone Massimo , La Via Francesco , Zielinski Marcin , Roccaforte Fabrizio
Published: January 2020

In spite of its great promise for energy‐efficient power conversion, the electronic quality of cubic silicon carbide (3C‐SiC) on silicon is currently limited by the presence of a variety of extended defects in the heteroepitaxial material. However, the specific role of the different defects on the electronic transport is still under debate. A macro‐ and nanoscale characterization of Schottky contacts on 3C‐SiC/Si is carried out to elucidate the impact of the anti‐phase boundaries (APBs) and stacking faults (SFs) on the forward and reverse current–voltage characteristics of these devices. Current mapping of 3C‐SiC by conductive atomic force microscopy directly shows the role of APBs as the main defects responsible of the reverse bias leakage, while both APBs and SFs are shown to work as preferential current paths under forward polarization. Distinct differences between these two types of defects are also confirmed by electronic transport simulations of a front‐to‐back contacted SF and APB. These experimental and simulation results provide a picture of the role played by different types of extended defects on the electrical transport in vertical or quasi‐vertical devices based on 3C‐SiC/Si, and can serve as a guide for improving material quality by defects engineering.
Kinetic Resolution of Racemic 2‐Hydroxyarylketones by Asymmetric Esterification: Investigation of the Influence of the Co‐Base on the Selectivity
Authors: Murata Takatsugu , Futami Kengo , Ishikawa Ryo , Ono Keisuke , Nakata Kenya , Shiina Isamu
Published: January 2020

An efficient kinetic resolution of a variety of racemic 2‐hydroxyarylketone derivatives was developed by asymmetric esterification protocol using diphenylacetic acid, pivalic anhydride, and a catalytic amount of (R)‐benzotetramisole ((R)‐BTM). It was revealed that employing a tertiary amine as a co‐base in this reaction is not necessary to achieve high s‐values. All conducted reactions proceeded smoothly with good s‐values under the optimized reaction conditions, irrespective of the steric and electronic nature of the substituents on the aromatic rings of the substrates. The most stable transition state of the reaction was determined by density functional theory (DFT) calculations.
Polycyclic Aromatic Hydrocarbon‐/Heterocycle‐Embedded Porphyrinoids
Authors: Laxman Kandala , Kumar Ankit , Ravikanth Mangalampalli
Published: January 2020

Porphyrinoids in which one or two pyrrole rings are replaced with polycyclic aromatic hydrocarbons/heterocycles such as naphthalene, phenanthrene, biphenyl, bipyridine, or phenanthroline are a new class of porphyrinoids represented as polycyclic aromatic hydrocarbon (PAH)‐/heterocycle‐embedded porphyrinoids. These macrocycles possess the structural features of both polycyclic aromatic hydrocarbons/heterocycles and cyclic polypyrrolic porphyrinoids. The PAH‐embedded porphyrinoids have drawn significant interest in recent times because of the following: (1) these macrocycles exhibit different π‐conjugation pathways unlike porphyrinoids, which exhibit circular conjugation pathways in their macrocyclic rings with various molecular structures; (2) the PAHs embedded macrocycles show variable degree of aromaticity which varies from weak aromaticity to antiaromaticity and (3) the PAHs embedded porphyrinoids provide unique ligand environment to form stable coordination and organometallic complexes in which metals may show uncommon oxidation states and unusual reactivity. All these above‐listed features depend on polycyclic aromatic hydrocarbon/heterocycle moiety present as a part of porphyrinoid macrocyclic framework. This Minireview focuses on the synthesis of different polycyclic aromatic hydrocarbon‐/heterocycle‐embedded porphyrins, contracted porphyrins and expanded porphyrins and briefly discusses their structural, spectral, aromatic and coordination properties.
Scn8a Antisense Oligonucleotide Is Protective in Mouse Models of SCN8A Encephalopathy and Dravet Syndrome
Authors: Lenk Guy M. , Jafar‐Nejad Paymaan , Hill Sophie F. , Huffman Lucas D. , Smolen Corrine E. , Wagnon Jacy L. , Petit Hayley , Yu Wenxi , Ziobro Julie , Bhatia Kritika , Parent Jack , Giger Roman J. , Rigo Frank , Meisler Miriam H.
Published: January 2020

Objective

SCN8A encephalopathy is a developmental and epileptic encephalopathy (DEE) caused by de novo gain‐of‐function mutations of sodium channel Nav1.6 that result in neuronal hyperactivity. Affected individuals exhibit early onset drug‐resistant seizures, developmental delay, and cognitive impairment. This study was carried out to determine whether reducing the abundance of the Scn8a transcript with an antisense oligonucleotide (ASO) would delay seizure onset and prolong survival in a mouse model of SCN8A encephalopathy.

Methods

ASO treatment was tested in a conditional mouse model with Cre‐dependent expression of the pathogenic patient SCN8A mutation p.Arg1872Trp (R1872W). This model exhibits early onset of seizures, rapid progression, and 100% penetrance. An Scn1a
+/− haploinsufficient mouse model of Dravet syndrome was also treated. ASO was administered by intracerebroventricular injection at postnatal day 2, followed in some cases by stereotactic injection at postnatal day 30.

Results

We observed a dose‐dependent increase in length of survival from 15 to 65 days in the Scn8a‐R1872W/+ mice treated with ASO. Electroencephalographic recordings were normal prior to seizure onset. Weight gain and activity in an open field were unaffected, but treated mice were less active in a wheel running assay. A single treatment with Scn8a ASO extended survival of Dravet syndrome mice from 3 weeks to >5 months.

Interpretation

Reduction of Scn8a transcript by 25 to 50% delayed seizure onset and lethality in mouse models of SCN8A encephalopathy and Dravet syndrome. Reduction of SCN8A transcript is a promising approach to treatment of intractable childhood epilepsies. Ann Neurol 2020;87:339–346
Active and Unidirectional Acceleration of Biaryl Rotation by a Molecular Motor
Authors: Uhl Edgar , Mayer Peter , Dube Henry
Published: January 2020

Light‐driven molecular motors possess immense potential as central driving units for future nanotechnology. Integration into larger molecular setups and transduction of their mechanical motions represents the current frontier of research. Herein we report on an integrated molecular machine setup allowing the transmission of potential energy from a motor unit onto a remote receiving entity. The setup consists of a motor unit connected covalently to a distant and sterically encumbered biaryl receiver. By action of the motor unit, single‐bond rotation of the receiver is strongly accelerated and forced to proceed unidirectionally. The transmitted potential energy is directly measured as the extent to which energy degeneration is lifted in the thermal atropisomerization of this biaryl. Energy degeneracy is reduced by more than 1.5 kcal mol−1, and rate accelerations of several orders of magnitude in terms of the rate constants are achieved.
Nickel/Photoredox‐Catalyzed Asymmetric Reductive Cross‐Coupling of Racemic α‐Chloro Esters with Aryl Iodides
Authors: Guan Haixing , Zhang Qianwen , Walsh Patrick J. , Mao Jianyou
Published: January 2020

A unique nickel/organic photoredox co‐catalyzed asymmetric reductive cross‐coupling between α‐chloro esters and aryl iodides is developed. This cross‐electrophile coupling reaction employs an organic reductant (Hantzsch ester), whereas most reductive cross‐coupling reactions use stoichiometric metals. A diverse array of valuable α‐aryl esters is formed under these conditions with high enantioselectivities (up to 94 %) and good yields (up to 88 %). α‐Aryl esters represent an important family of nonsteroidal anti‐inflammatory drugs. This novel synergistic strategy expands the scope of Ni‐catalyzed reductive asymmetric cross‐coupling reactions.
Highly Crystalline and Semiconducting Imine‐Based Two‐Dimensional Polymers Enabled by Interfacial Synthesis
Authors: Sahabudeen Hafeesudeen , Qi Haoyuan , Ballabio Marco , Položij Miroslav , Olthof Selina , Shivhare Rishi , Jing Yu , Park SangWook , Liu Kejun , Zhang Tao , Ma Ji , Rellinghaus Bernd , Mannsfeld Stefan , Heine Thomas , Bonn Mischa , Cánovas Enrique , Zheng Zhikun , Kaiser Ute , Dong Renhao , Feng Xinliang
Published: January 2020

Single‐layer and multi‐layer 2D polyimine films have been achieved through interfacial synthesis methods. However, it remains a great challenge to achieve the maximum degree of crystallinity in the 2D polyimines, which largely limits the long‐range transport properties. Here we employ a surfactant‐monolayer‐assisted interfacial synthesis (SMAIS) method for the successful preparation of porphyrin and triazine containing polyimine‐based 2D polymer (PI‐2DP) films with square and hexagonal lattices, respectively. The synthetic PI‐2DP films are featured with polycrystalline multilayers with tunable thickness from 6 to 200 nm and large crystalline domains (100–150 nm in size). Intrigued by high crystallinity and the presence of electroactive porphyrin moieties, the optoelectronic properties of PI‐2DP are investigated by time‐resolved terahertz spectroscopy. Typically, the porphyrin‐based PI‐2DP 1 film exhibits a p‐type semiconductor behavior with a band gap of 1.38 eV and hole mobility as high as 0.01 cm2 V−1 s−1, superior to the previously reported polyimine based materials.
A Scalable Metal‐, Azide‐, and Halogen‐Free Method for the Preparation of Triazoles
Authors: Clark Peter R. , Williams Glynn D. , Hayes Jerome F. , Tomkinson Nicholas C. O.
Published: January 2020

A scalable metal‐, azide‐, and halogen‐free method for the synthesis of substituted 1,2,3‐triazoles has been developed. The reaction proceeds through a 3‐component coupling of α‐ketoacetals, tosyl hydrazide, and a primary amine. The reaction shows outstanding functional‐group tolerance with respect to both the α‐ketoacetal and amine coupling partners, providing access to 4‐, 1,4‐, 1,5‐, and 1,4,5‐substituted triazoles in excellent yield. This robust method results in densely functionalised 1,2,3‐triazoles that remain challenging to prepare by azide–alkyne cycloaddition (AAC, CuAAC, RuAAC) methods and can be scaled in either batch or flow reactors. Methods for the chemoselective reaction of either aliphatic amines or anilines are also described, revealing some of the potential of this novel and highly versatile transformation.
9,9‐Dimethylxanthene Derivatives with Room‐Temperature Phosphorescence: Substituent Effects and Emissive Properties
Authors: Liao Qiuyan , Gao Qihe , Wang Jiaqiang , Gong Yanbing , Peng Qian , Tian Yu , Fan Yuanyuan , Guo Haojie , Ding Dan , Li Qianqian , Li Zhen
Published: January 2020

Room‐temperature phosphorescence (RTP) emitters with ultralong lifetimes are emerging as attractive targets because of their potential applications in bioimaging, security, and other areas. But their development is limited by ambiguous mechanisms and poor understanding of the correlation of the molecular structure and RTP properties. Herein, different substituents on the 9,9‐dimethylxanthene core (XCO) result in compounds with RTP lifetimes ranging from 52 to 601 ms, which are tunable by intermolecular interactions and molecular configurations. XCO‐PiCl shows the most persistent RTP because of its reduced steric bulk and multiple sites of the 1‐chloro‐2‐methylpropan‐2‐yl (PiCl) moiety for forming intermolecular interactions in the aggregated state. The substituent effects reported provide an efficient molecular design of organic RTP materials and establishes relationships among molecular structures, intermolecular interactions, and RTP properties.
A Photoactivated Cu–CeO2 Catalyst with Cu‐[O]‐Ce Active Species Designed through MOF Crystal Engineering
Authors: Wang Feifan , Tian Jie , Li Mengzhu , Li Weizhen , Chen Lifang , Liu Xiaozhi , Li Jian , Muhetaer Aidaer , Li Qi , Wang Yuan , Gu Lin , Ma Ding , Xu Dongsheng
Published: January 2020

Fully utilizing solar energy for catalysis requires the integration of conversion mechanisms and therefore delicate design of catalyst structures and active species. Herein, a MOF crystal engineering method was developed to controllably synthesize a copper–ceria catalyst with well‐dispersed photoactive Cu‐[O]‐Ce species. Using the preferential oxidation of CO as a model reaction, the catalyst showed remarkably efficient and stable photoactivated catalysis, which found practical application in feed gas treatment for fuel cell gas supply. The coexistence of photochemistry and thermochemistry effects contributes to the high efficiency. Our results demonstrate a catalyst design approach with atomic or molecular precision and a combinatorial photoactivation strategy for solar energy conversion.
Influence of rotation angle of a triangular tube with a built‐in twisted tape on the thermal‐exergy efficiency and entropy generation of nanofluids in the heat exchange system
Authors: Qi Cong , Li Chunyang , Zhao Gongbin , Liu Maoni , Han Dongtai
Published: January 2020

In order to investigate the thermal‐exergy efficiency and entropy generation of nanofluids flowing through a triangular tube with a built‐in twisted tape, a heat exchange system is designed and established. Deionized water and three mass concentration nanofluids (ω = 0.1 wt%, 0.3 wt%, and 0.5 wt%) are applied as the heat‐transfer mediums flowing through three different rotation angle (α = 0°, 30°, and 60°) triangular tubes, respectively. Thermal efficiency index (η) and entropy generation (S) are used to characterize the performance of the heat exchange system. It is proved that the increase of nanoparticles can not only effectively promote the heat transfer effect but also augment the pressure loss. Nusselt number of nanofluids is increased by 20.2% on average, whereas the flow resistance coefficient is increased by 10.1% on average. Based on the thermal efficiency index, the data demonstrate that ω = 0.5 wt% nanofluids in the triangular tube at α = 0° can make the most effective use of energy, whose value could reach 1.32 at most. Exergy efficiency of nanofluids in the heat exchange system can be evidently heightened under the same pumping power and flow rate. Entropy production of 0.1 wt% nanofluids is the smallest.
Event‐triggered sliding mode control for time‐delay uncertain systems
Authors: Feng Jianlin , Hao Fei
Published: January 2020

This paper addresses the event‐triggered sliding mode control to solve the stabilization problem of linear uncertain systems with time delays. First, the sufficient conditions for the existence of linear sliding surface for uncertain systems are derived in terms of linear matrix inequalities. Then, the sufficient conditions for the existence of linear sliding surface for time‐delay uncertain systems are given. The robust controller is designed based on the event‐triggering mechanism to stabilize the time‐delay uncertain systems. Moreover, it is proved that under the proposed event‐triggered sliding mode control, the corresponding triggering instants does not exhibit accumulation of triggering instants. Finally, a numerical example is given to illustrate the efficiency and feasibility of the proposed results.