bluuebunny/crossref_metadata_2025 huggingface dataset:
Clarification of the structure of “hybrid forces”
Authors: Tikhanychev Oleg Vasilyevich
Published: April 2021

The subject of this research is the “hybrid wars”, while the object is the “hybrid forces” as a means of conducting hybrid wars. The author establishes that that currently in assessment of “hybrid forces”, the latter imply military and irregular formations opposing on the battlefield. At the same time, the analysis of the content of “hybrid wars” demonstrates that the structure of “hybrid forces” should be understood in a broader sense, considering procurement and all-round support, including those carried out covertly. This approach provides a more accurate assessment of “hybrid wars” and its actors. The main conclusion of consists in the proposal to expand the structure of “hybrid forces”, alight in with the structure of modern” hybrid” conflicts. The novelty of this research lies in the fact that based on clarification of the actors and structure of “hybrid forces”, the author formulates recommendations on clarification of the mechanisms for assessing course of “hybrid” wars, analysis of the possible vectors for “hybrid” actions;  as well as underlines the need for regulation of international legislation in the area of conducting armed conflicts and their actors. The analysis of open sources describing the subject area shows that this problem was not previously solved in such a statement
Social networks as an instrument of PSYOP in foreign policy: challenge for the national security
Authors: Odnoral Oleg Igorevich
Published: April 2021

The object of this research is the process of creating political discourse, setting the “agenda” via social media as foreign policy instrument and a threat to national security of the country. The article explores the role of the online platform in shaping public opinion and discourse in political interests. The subject of this research is the social media (social networks, video and image hosting services, blogs, etc.) Particular attention is given to structurization of the concept of social media, social networks as the instruments that form social reality and affect public opinion. Emphasis is placed on the technical aspects of the types of social networks, control, thereof. Comparative analysis is conducted on the practice of using Internet resources in China, and experience of creating the Golden Shield Project. The scientific novelty of consists in the cross-scientific analysis on the basis of the interpretive pattern of social constructionism, what distinguishes this work from the vast majority of similar research of dedicated to the use of social media as an instrument of political technologies and PSYOP. Being a cross-scientific analysis at the intersection of IT (information technology), international relations (political science), and social psychology, the study leans on the theoretical concepts of political realism and neorealism, psychological constructivism and behavioral psychology. The author underlines the importance of comprehensive approach towards leveling the potential threats of using social media as an instrument of PSYOP. First and foremost, it pertains to the development of a coherent all-encompassing system with ideological and value foundation for creating the discourse. The article describes the relevant approaches towards the “sovereign Internet"; carries out comparative analysis of the Chinese experience and Russian ineffective initiatives, such as blocking separately resources, shortage of public-private partnership in the IT sector (by analogy with the extremely successful experience of China in this sphere). The author offers a general frame of possible steps on ensuring national security in the online platform of social media.
Anti-corruption education and outreach as a factor promoting investment attractiveness of the country
Authors: Pavlov Pavel Vladimirovich , Godunov Igor Valentinovich , Zashchitina Elena Konstantinovna
Published: April 2021

This article examines the correlation between the country’s investment attractiveness and the level of corruption therein. The key goal of this research consist in the creation of comprehensive curriculum for anti-corruption education and outreach, the implementation of which would significantly reduce the level of corruption in Russia, and thereby improve its investment attractiveness on the international arena. The object of this research is the mechanisms for improving investment attractiveness of the country in the global market; one of such mechanisms is the reduction of corruption component. The subject of this research is the practices of anti-corruption education and outreach used by the world leading countries aimed at lowering the level of corruption. The information framework is comprised  of the official statistics of the World Bank, as well as expert reports published in the media. Based on the established correlation between these factors, the article provides the examples of measures for reducing the level of corruption implemented in Russia and the leading world countries. The result of the work consists in the development of comprehensive curriculum for anti-corruption education, which can be used on the regional or federal level for achieving a synergistic effect. This article is intended for the scholars and pedagogues, officers of the executive branch, state and municipal officials responsible for the implementation of national anti-corruption plans, as well as other experts dealing with anti-corruption issues.
Steps towards a post-nonclassical methodology of higher education (logical-semantic approach)
Authors: Leskova Inna Aleksandrovna
Published: April 2021

Post-nonclassical nature of changes in education actualizes the need for transforming its methodological grounds. The goal of this article is to offer a new perspective of interpretation of the methodology of education, as well as trace the steps towards its post-nonclassical transformation. The research leans on the theoretical-methodological provisions of the logical-semantic approach, which focuses on the laws of conceptualization. The article explores the objective and subjective logical-semantic patterns of the work of mind characteristic to classical and post-nonclassical worldview. Congruence with the objective logic of the work of mind of methodological grounds in educational practice of the higher school is confirmed by examples. The examples show the limitations of their methodological capabilities in solving modern problems of knowledge and practice. The limitations of their methodological capabilities in solution of the relevant cognitive tasks and practice are indicated. The article suggest and analyzes the methodological principle of the subject, which determines the human-sizedness and communicative alignment of methodological system of education, which ensures its compliance with the post-nonclassical methodology of science. The author demonstrates a number of changes within the education system, which are methodologically substantiated by the principle of the subject. The highlighted logical-semantic patterns of the work of mind can be used as an instrument for understanding and explaining the components of educational process, as well as their design and management. The author proposes a nonlinear structure of the content of education. It can underlie the creation of learning model, which would consider the individual characteristics of students and fulfill the educational potential of the traditional and innovative teaching systems.
Educational meaning of on-location practice for the students of architectural specialties
Authors: Goncharova Natalia Vladimirovna , Baklyskaia Larisa Evgen'evna , Zadokhina Maria Borisovna , Denisova Alisa Aleksandrovna
Published: April 2021

The subject of this research is the vocational training of the students of architectural specialties and the the need for on-location practices in the Russian and foreign historical cities. The relevance of this topic is defined by the fact that the importance of such practices is questioned in the context of development of new educational curricula. Analysis is conducted on the historical aspect, the role of practice in vocational training, as well as peculiarities of perception of reality by the future architects and designers and cognitive activity in the open-air environment. The author outlines and substantiates the goals and tasks aimed at the development of knowledge and skills acquired the students during on-location practice. The research leans on the experience of conducting practices by the Institute of Architecture and Design of the Pacific National University in Russia and abroad. The authors discuss the positions of the planners, heads and participants of the on-location practices. The conclusion is made that such practices and not only the immersion into the historical environment, but its grasp by means of visual arts, which is an integral part of vocational education. The experience acquired by the student in the course of on-location practice is irreplaceable and necessary for professional growth of future architects and designers in accordance with modern requirements.
Characteristics of the degrees of modalation and predicativation of word forms such as “it is evident” in asyndetic complex sentence
Authors: Shigurov Viktor Vasil'evich
Published: April 2021

This article examines the mechanism of transposition of linguistic units from short adjectives into introductory-modal units and predicatives. The object of this research is word forms such as “it is evident”, which in asyndetic complex sentences represent a zone of hybrid structures on the scale of modalation. The subject of this research is the combinatorics and proportion of the characteristics of adjectives, introductory-modal words and expressions, and impersonal-predicative words (predicatives) within the structure of hybrids. The relevance of this work is substantiated by the need for studying the mechanism of interaction between grammatical and lexical within the structure of word forms involved in one or more transpositional processes on the level of parts of speech and inter-part-of-speech categories. On thee example of deadjectival word form “it is evident”, the author calculates the indexes of modalation and predicativation of short adjectives in the zone of hybrid structures represented by asyndetic complex sentences with explicative relations between the predicative parts. It is established that the hybrid “it is evident” demonstrates 56 % correspondence of differential characteristics with characteristics of the original nuclear short adjective “evident” in the meaning of “available for visible perception”, 27 % correspondence with the characteristics of nuclear introductory- modal word “evident” in the meaning of “probably”, and 67% correspondence with the characteristics of nuclear predicative “it’s a shame” with the semantics of emotional state of a person and moral-ethical evaluation of his behavior.
El esquema comunicativo de Roman Jakobson entre lenguas y continentes: historia cruzada del modelo teórico
Authors: Pilshchikov Igor
Published: April 2021

The article analyzes the evolution of Roman Jakobson’s definition of the poetic function and its place in the multifunctional schema of the act of communication that he developed from the 1920s to the 1950s. This evolution is an example of the productive reinterpretation of a concept in the process of multiple cross-cultural transfers, including translations from one language to another (Russian, Czech, French, English), the shift from one conceptual system to another (Formalism, Structuralism, semiotics and cybernetics), and adaptive transformation of the communication models developed by Jakobson’s predecessors (Husserl, Bühler, Shannon). Understanding Jakobson’s schema requires that we elucidate the roles that essential formalist and structuralist concepts played in its formation and identify their translated equivalents in his own texts. This discussion is prompted by the adjustments to Jakobson’s model proposed by Mikhail Bakhtin and Yuri Lotman.
Aldring i et samisk samfunn
Authors: Anderssen Jorid S. , Gjernes Trude
Published: April 2021

Rapporten presenterer resultater fra prosjektet «Aldring i samiske befolkningsområder» på oppdrag fra Helsedirektoratet. Oppdraget er utført av Jorid Anderssen, UiT Norges Arktiske universitet og Trude Gjernes, Nord universitet. Oppdraget er en del av oppfølgingen av regjeringens strategi for et aldersvennlig samfunn Flere år, flere muligheter.

Formålet med denne rapporten er å gi et innblikk i hvordan innbyggere i et ruralt samisk samfunn beskriver sitt samfunn, sine levemåter, planer og forventinger til aldring og alderdom, og hvilken plass aldring har i kommunens plandokumenter. Vi har gjennomført undersøkelsen i en kommune og har i den forbindelse fått tilgang til kommunens plandokumenter, og intervjuet kommunale ledere og innbyggere.
Marine microalgae co-cultured with floc-forming bacterium: Insight into growth and lipid productivity
Authors: Yee Chin Sze , Okomoda Victor Tosin , Hashim Fakriah , Waiho Khor , Sheikh Abdullah Siti Rozaimah , Alamanjo Cosmas , Abu Hasan Hassimi , Muzalina Mustafa Emienour , Kasan Nor Azman
Published: April 2021

This study investigated the effect of co-culturing microalgae with a floc-forming bacterium. Of the six microalgae isolated from a biofloc sample, only Thalassiosira weissflogii, Chlamydomonas sp. and Chlorella vulgaris were propagated successfully in Conway medium. Hence, these species were selected for the experiment comparing microalgae axenic culture and co-culture with the floc-forming bacterium, Bacillus infantis. Results obtained showed that the co-culture had higher microalgae biomass compared to the axenic culture. A similar trend was also observed concerning the lipid content of the microalgae-bacterium co-cultures. The cell number of B. infantis co-cultured with T. weissflogii increased during the exponential stage until the sixth day, but the other microalgae species experienced a significant early reduction in cell density of the bacteria at the exponential stage. This study represents the first attempt at co-culturing microalgae with B. infantis, a floc-forming bacterium, and observed increased biomass growth and lipid accumulation compared to the axenic culture.
Implications of Philately in Promoting the Protected Natural Areas (VII): Retezat National Park, Romania
Authors: Cioruța Bogdan-Vasile , Coman Mirela , Pop Alexandru Leonard
Published: April 2021

The protected natural areas have a special beauty, manifested in terms of landscapes that delight the eye, but especially in the species of flora and fauna that populate them. However, not many of these areas are accessible to the general public. As a result, they are not known and appreciated at their true value. To make them known to all and to show the implications of thematic philately in the promotion of protected areas. This paper aims to discuss a series of significant philatelic features related to the Retezat National Park. The present study is based on an impressive series of stamps, first-day envelopes, occasional envelopes, and illustrated postcards, including maxima, which were collected, indexed, and analyzed in stages. Besides, both official pieces (made under the auspices of the Romanian postal administration) and pieces made for private by entities or collectors are studied. It is thus recorded that the thematic philately is richly nuanced by pieces referring to the Retezat National Park, which implicitly leads to greater visibility of it among the population.
Constraint and Unconstraint of Vector Autoregressive Model; Using GDP Growth Rate of Agriculture, Industries, Building/Construction, Whole-Sale/Retail and Services in Nigeria
Authors: Moses Ekpenyong, Aniedi. , Essi Isaac, Didi
Published: April 2021

In this research, multivariate Time Series was adopted to model the Gross Domestics Product (GDP) growth rate of Nigeria on five (5) variables namely: Agriculture, Industries, Building/construction, Wholesales/Retails trade and Services The data was collected from National Bureau of Statistics, range quarterly from 1985 to 2017, a total of 33years. Real (R) software was used as a tool to analyze the model. The data were grouped into 10 pairs of 2 parameter variables, 10 pairs of 3 parameters variables, 5 pairs of 4 parameters variables, and the complete 5 parameter variables. In each group, the best model was selected and Lag's using Akaike Information Criteria, then the unconstrained (vector autoregressive) AIC of the model was compared with that of constrained (simplified vector autoregressive) AIC model. The unconstraint models with AIC values (-11.973, -17.1111, -22.1823, and 25.8996) at lag (5) was compared with that of constraint models with AIC values of (-12.5116, -17.5298, -22.2894 and -25.9916), the outcome showed that constraint models performed better than unconstraint models.
Indigenous Chicken Productivity and Associated Farm-Level Attributes among Producers in the Western Parts of Kenya
Authors: Cheruiyot Joseph Kipkorir , Adhiaya Merina
Published: April 2021

Indigenous chicken production is an important sub-sector in Kenya. About 90% of rural communities keep indigenous chicken in small flocks. They provide the much needed high value protein and income for the rural households. Despite its importance; the productivity of the sub-sector greatly varies depending on the management systems deployed by the producers. The management systems are thought to be influenced by demographic; socio-economic and information literacy factors. This study investigated the potential links between these factors and indigenous chicken productivity in two regions in the Western parts of Kenya. The survey study adopted a descriptive approach. Semi-structured interview schedules were used to collect data from a sample of 106 smallholder producers. Purposive and multi-stage sampling techniques were used to select the participants from among producers who had shown interest in the commercialization of indigenous chicken following awareness meetings conducted by public extension agents in the two regions. Data was analyzed by use of descriptive statistics and correlation estimates using Kendalls’ tau-b and Goodman-Kruskalls’ Gamma coefficients. Gender; education levels; flock size; information literacy and access to markets had significant association (P < .05) with some indigenous chicken productivity indicators that were investigated.
A Moisture‐Driven Actuator Based on Polydopamine‐Modified MXene/Bacterial Cellulose Nanofiber Composite Film
Authors: Yang Luyu , Cui Jian , Zhang Lei , Xu Xuran , Chen Xiao , Sun Dongping
Published: April 2021

As a new 2D material, MXene (Ti3C2Tx) shows great potential as a smart multifunctional humidity‐responsive actuator due to its high hydrophilicity and conductivity but suffers from ambient oxidation and mechanical brittleness. Inspired by the mussels, the authors overcome these weaknesses by designing and fabricating a nacre‐like and lamellar‐structured composite film that consists of polydopamine‐modified MXene and bacterial cellulose nanofibers, which shows improved properties as a moisture‐driven actuator. The actuator has high conductivity (2848 S cm–1), excellent tensile strength (406 MPa), and toughness (15.3 MJ m–3). Moreover, the actuator is highly sensitive to moisture with the advantages of fast response (1.6 s), large deformation (176°), and high actuation force output (6.5 N m–2). It is additionally demonstrated that the actuator works as the electrical switch, robotic arm, and motor in a moisture‐driven manner. Overall, it is believed that this work improves the drawbacks of current MXene‐based actuators, laying the groundwork for their wider applications as moisture‐driven devices.
Design of a Multilayered Oxygen‐Evolution Electrode with High Catalytic Activity and Corrosion Resistance for Saline Water Splitting
Authors: Li Jihong , Liu Yipu , Chen Hui , Zhang Zhankai , Zou Xiaoxin
Published: April 2021

The realization of seawater electrolysis requires high‐performing anode materials that should possess good catalytic activity, stability, and specificity for the oxygen evolution reaction (OER) as well as high resistance toward chloride corrosion. Herein, the design of a multilayered oxygen‐evolution electrode is reported to meet the multiple needs of anode material for saline water splitting. The multilayered electrode is synthesized through direct thermal boronization of commercially available NiFe alloy plate with boron powder, followed by electrochemical oxidation. And this electrode is composed of the surface oxidized NiFeBx alloy layer, the NiFeBx alloy interlayer, and the NiFe alloy substrate. The boron species are present in the form of metaborate in the outermost oxidized NiFeBx layer, and their existence is conductive to the generation and stabilization of the catalytic active phase γ‐(Ni,Fe)OOH. The introduction of NiFeBx interlayer effectively prevents the excessive oxidative corrosion of the anode material in the electrolyte containing chloride ions.
Microtissue Geometry and Cell‐Generated Forces Drive Patterning of Liver Progenitor Cell Differentiation in 3D
Authors: Berg Ian C. , Mohagheghian Erfan , Habing Krista , Wang Ning , Underhill Gregory H.
Published: April 2021

3D microenvironments provide a unique opportunity to investigate the impact of intrinsic mechanical signaling on progenitor cell differentiation. Using a hydrogel‐based microwell platform, arrays of 3D, multicellular microtissues in constrained geometries, including toroids and cylinders are produced. These generated distinct mechanical profiles to investigate the impact of geometry and stress on early liver progenitor cell fate using a model liver development system. Image segmentation allows the tracking of individual cell fate and the characterization of distinct patterning of hepatocytic makers to the outer shell of the microtissues, and the exclusion from the inner diameter surface of the toroids. Biliary markers are distributed throughout the interior regions of micropatterned tissues and are increased in toroidal tissues when compared with those in cylindrical tissues. Finite element models of predicted stress distributions, combined with mechanical measurements, demonstrates that intercellular tension correlates with increased hepatocytic fate, while compression correlates with decreased hepatocytic and increased biliary fate. This system, which integrates microfabrication, imaging, mechanical modeling, and quantitative analysis, demonstrates how microtissue geometry can drive patterning of mechanical stresses that regulate cell differentiation trajectories. This approach may serve as a platform for further investigation of signaling mechanisms in the liver and other developmental systems.
Recent Progress in Flexible Tactile Sensors for Human‐Interactive Systems: From Sensors to Advanced Applications
Authors: Pyo Soonjae , Lee Jaeyong , Bae Kyubin , Sim Sangjun , Kim Jongbaeg
Published: April 2021

Flexible tactile sensors capable of measuring mechanical stimuli via physical contact have attracted significant attention in the field of human‐interactive systems. The utilization of tactile information can complement vision and/or sound interaction and provide new functionalities. Recent advancements in micro/nanotechnology, material science, and information technology have resulted in the development of high‐performance tactile sensors that reach and even surpass the tactile sensing ability of human skin. Here, important advances in flexible tactile sensors over recent years are summarized, from sensor designs to system‐level applications. This review focuses on the representative strategies based on design and material configurations for improving key performance parameters including sensitivity, detection range/linearity, response time/hysteresis, spatial resolution/crosstalk, multidirectional force detection, and insensitivity to other stimuli. System‐level integration for practical applications beyond conceptual prototypes and promising applications, such as artificial electronic skin for robotics and prosthetics, wearable controllers for electronics, and bidirectional communication tools, are also discussed. Finally, perspectives on issues regarding further advances are provided.
Visibly Transparent Radiative Cooler under Direct Sunlight
Authors: Kim Minkyung , Lee Dasol , Son Soomin , Yang Younghwan , Lee Heon , Rho Junsuk
Published: April 2021

Transparency is an important characteristic in practical applications of radiative cooling, but the transmitted sunlight trapped in an inner space is generally the main cause of the increasing temperature. A transparent radiative cooler that can lower a temperature during the daytime by transmitting visible light, reflecting near‐infrared (NIR) light, and radiating thermal energy through the atmospheric window is proposed. In contrast to transparent selective emitters that transmit most of the incoming solar irradiance under direct sunlight and opaque radiative coolers that reflect all solar energy, the proposed cooler achieves transparency and the cooling effect simultaneously by selectively blocking solar absorption in the NIR regime. Outdoor rooftop measurements confirm that the cooler can reduce i) the inner temperature of an absorbing system and ii) its own temperature when combined with commercially available paints. During daytime, the cooler provides a temperature reduction of a maximum 14.4 °C and 10.1 °C for the inner and own temperature, respectively, and of an average 5.2 °C and 4.3 °C, respectively, in comparison to the transparent selective emitter. The proposed cooler can reduce the temperature during the daytime while maintaining transparency, confirming its possibilities in practical applications such as passive diurnal cooling of vehicles or buildings and compatibility with current paint technologies for aesthetic use.
Atomically Thin Nanosheets Confined in 2D Heterostructures: Metal‐Ion Batteries Prospective
Authors: Khan Abbas , Azadmanjiri Jalal , Wu Bing , Liping Liao , Sofer Zdeněk , Min Jiakang
Published: April 2021

Owing to the surge of energy storage devices, lithium and beyond‐lithium metal ion batteries (MIBs) have gained considerable research attention. The large size and multivalent ions drastically deteriorate the performance of conventional battery electrode materials which demands unique types of structures in order to fulfill the electrode requirements of next‐generation MIBs. Developing atomically thin nanosheets confined in 2D heterostructures is a favorable choice to synergistically handle the deficiencies of individual 2D materials and achieve distinct physical and electrochemical properties, retaining their 2D features. This article sheds light on the significance and characteristics of graphene‐based and beyond‐graphene 2D heterostructures as electrode materials in lithium‐ion, sodium‐ion, potassium‐ion, magnesium‐ion, and aluminum‐ion batteries. In this regard, the pathways for the selection of 2D heterostructures electrode materials and their possible geometric configurations are first recognized. Second, the fundamental science, underlying charge storage mechanisms, and robust interfacial charge transfer processes in 2D heterostructures are discussed comprehensively in the context of recent computational studies. Third, the recent state‐of‐the‐art experimental approaches for the fabrication of novel 2D heterostructures and their performance as anode and cathode materials for MIBs are discussed systematically. Finally, the current challenges facing 2D heterostructures and potential future research directions in the context of advanced MIBs are highlighted.
Ultramicroporous carbon granules with narrow pore size distribution for efficient CH4 separation from coal‐bed gases
Authors: Dong Ze , Li Bei , Shang Hua , Zhang Peixin , Chen Shixia , Yang Jiangfeng , Zeng Zheling , Wang Jun , Deng Shuguang
Published: April 2021

The adsorptive separation of CH4 from low‐grade coal‐bed gas can be performed at decentralized and remote coal mines, and it uses more energy‐ and is cost‐efficient than the traditional cryogenic distillation process. Herein, we present a facile method to prepare ultramicroporous carbon granules with a narrow pore‐size distribution at 0.5–0.6 nm. To our knowledge, such centered and uniform pore‐size distribution in carbon granules has never been reported. The carbon granules can be directly utilized in adsorption columns without a granulation or pelletization process. The granular oil‐tea‐shell‐derived porous carbon (GOC‐2) exhibited a record‐high CH4 uptake of 1.82 mmol/g and CH4/N2 selectivity of 5.8 at 1.0 bar and 298 K among carbon granules. The excellent CH4/N2 separation performances were confirmed from the results of dynamic breakthrough experiments and pressure swing adsorption simulations. This work provides a novel strategy for developing ultramicroporous carbon granules and guides the future design of efficient CH4/N2 separation adsorbents.
Photosynthetic heat tolerance in plants with different foliar water ‐uptake strategies
Authors: Boanares Daniela , Lemos‐Filho José P. , Isaias Rosy M. S. , França Marcel G. C.
Published: April 2021

Premise

The distribution and even the survival of plant species are influenced by temperature. In an old climatically buffered infertile landscape (OCBIL) in Brazil, we previously characterized different strategies for foliar water uptake (FWU). It is possible that photosystem II tolerance to heat and excessive light intensity varies among species with different FWU capacities.

Methods

The relationship between FWU, photoinhibition, and thermotolerance was investigated in seven species from this ecosystem.

Results

The species with slow water absorption and high water absorption are those that presented less photoinhibition. Contrastingly, the species that have fast and low water absorption presented greater thermotolerance when their leaves are totally hydrated. However, when there is greater leaf dehydration, the most thermotolerant species were those with slow but high water absorption.

Conclusions

Foliar water uptake is an important trait for plants to tolerate excessive light intensity and higher temperatures. Plants in this OCBIL may be differentially affected by future global warming, and the best strategy to deal with this expected climate change is with slow and high absorption of water.
Bifunctional Primary Amino‐thiourea Asymmetric Catalysis: The Imine‐Iminium Ion Mechanism in the Michael Addition of Nitromethane to Enone
Authors: Rufino Virginia C. , Pliego Josefredo R.
Published: April 2021

Primary‐amine thioureas are preeminent organocatalysts used in challenging asymmetric Michael‐type reactions, such as in the addition of nitromethane to enones. However, the complete reaction mechanism of this reaction has not yet been fully elucidated. Considering that the primary‐amine group could act via both base and iminium ion catalysis, both mechanisms were investigated in this work using theoretical methods. The calculations have indicated that the base catalysis is kinetically unfeasible, with very high overall ΔG≠. An imine‐iminium ion catalysis is a viable route. This mechanism requires the participation of an acid as a cocatalyst (additive) in several steps, including the formation of the imine. The rate‐determining step corresponds to the proton transfer from the nitromethane to the imine, forming the nitronate‐iminium ion‐pair intermediate. This complex reacts via nucleophilic attack of the nitronate ion to the electrophilic carbon of the iminium ion, forming a new C−C bond that determines the enantioselectivity of the reaction.
Asymmetric Transfer Hydrogenation of Trifluoromethylated Imines to Chiral α‐Trifluoromethylated Amines With Alcohol as The Hydrogen Source
Authors: Wang Zheting , Yang Chunhui , Chen Jingchao , Yang Fan , Khan Ruhima , Yang Yong , Qiao Xingfang , Su Zhimin , Fan Baomin
Published: April 2021

An efficient Pd/Zn co‐catalyzed method for the asymmetric transfer hydrogenation of trifluoromethylated imines to chiral α‐trifluoromethylated amines using methanol as the hydrogen source has been developed. The reaction showed good substrate scope and the products were obtained in excellent yields (up to 99%) with excellent enantioselectivity. The present methodology was compatible for the synthesis of deuterated chiral α‐trifluoromethylated amines. On using CD3OD as the deuterium source, deuterium incorporation up to 98% was observed without compromising the reaction outcome.
Reduzierte Arenkomplexe von Hafnium mit einem Triamidoaminliganden
Authors: Ghana Priyabrata , Schrader Sebastian , Rajeshkumar Thayalan , Spaniol Thomas P. , Englert Ulli , Maron Laurent , Okuda Jun
Published: April 2021

Hafniumkomplexe mit reduzierten Arenen der Formel [K(L)][Hf(Xy‐N3N)(Aren)] (Xy‐N3N={(3,5‐Me2C6H3)NCH2CH2}3N3−, L=THF, 18‐Krone‐6; Ar=C10H82−, C14H102−) ahmen die Chemie von Hafnium in seiner formalen Oxidationsstufe +II nach. Alle Verbindungen wurden nach Reduktion des Chloridokomplexes [HfCl(Xy‐N3N)(THF)] mit zwei Äquivalenten Kaliumnaphthalinid oder ‐anthracenid erhalten. Die reduzierende Natur und die Basizität des reduzierten Anthracenliganden wurden bei der Reaktion von Benzonitril und Azobenzol bzw. durch Deprotonierung von tert‐Butylacetylen untersucht. Die Reduktion von Benzonitril liefert ein anfängliches doppeltes Insertionsprodukt zweier Nitrile unter kinetischer Kontrolle, das nach Abgabe eines der inserierten Nitrile zu einem Hafniumimidokomplex als thermodynamisches Produkt umlagert. Die Reduktion von Azobenzol führte zu einem Diphenylhydrazido(2−)‐Komplex. Die Umsetzung von terminalen Alkinen mit dem Anthracen‐ oder Diphenylhydrazido(2−)‐Komplex führte zur selektiven Protonierung des entsprechenden dianionischen Liganden.
Preparation, characterization, and in vitro bioactivity of magnetic co‐polymer [N, N‐dimethylaminopropylacrylamide‐co‐1‐allylimidazole] as a new nanocarrier for delivery of cefotaxime
Authors: Alipour Arash , Babaei Shekardasht Mehrnaz , Gharbani Parvin
Published: April 2021

In this research, new magnetic nanoparticles (MNPs) conjugated radical co‐polymerization with N, N‐dimethylaminopropylacrylamide (N, N‐DMAPAAm) as a thermosensitive monomer and 1‐allylimidazole (AI) as a cross‐linker agent was prepared as a magnetic nanocomposite (MNC). The synthesized MNC were characterized by Fourier transform infrared spectroscopy, Elemental analysis (CHN), Field emission scanning electron microscopy, Vibrating Sample Magnetometer, and Thermo Gravimetric Analysis. Cefotaxime was selected as a model drug and was loaded into the synthesized polymer. The main factors of adsorption process such as pH, contact time, temperature, and eluent were evaluated and optimized. The mechanism of cefotaxime adsorption is explained by Langmuir isotherm. Also, in vitro cefotaxime delivery in the simulated gastric and intestinal fluids was investigated. The drug release profile revealed that about 30.35% of the adsorbed cefotaxime was released in the first 30 min. at pH =1.2 (simulated gastric fluid) and 62.65% was released during 15 h at pH =7.4 (simulated intestinal fluid).
Ancestry‐based variation in maxillary sinus anatomy: Implications for health disparities in sinonasal disease
Authors: Kim Suhhyun , Ward Lyndee A. , Butaric Lauren N. , Maddux Scott D.
Published: April 2021

Paranasal sinus drainage is mediated by mucociliary transport and gravity. However, human orthograde posture, along with the superior positioning of the maxillary sinus (MS) ostium, increases reliance on the mucociliary system. Previous research has thus suggested that differences in MS size and shape may impede mucociliary clearance, potentially contributing to disparities in sinusitis susceptibility. To further investigate this hypothesis, this study collected 29 three‐dimensional (3D) coordinate landmarks and seven linear measurements of MS morphology from 167 computed tomography (CT) scans of crania of European, East Asian, or Equatorial African ancestry. MANOVA results reveal the Asian‐derived individuals are characterized by both a significantly taller MS (F = 14.15, p <  0.0001) and a significantly greater distance from the MS floor to the ostium (F = 17.22, p <  0.0001) compared to those of European and African ancestry. A canonical variate (CV) analysis conducted on 3D landmark data provides corroborative results, distinguishing Asian‐derived individuals predominantly on the basis of a relatively lower MS floor. As a greater distance between the MS floor and ostium may impede mucociliary clearance, our results suggest MS anatomy may be a more prominent factor in chronic sinusitis among individuals of Asian ancestry compared to those of European and African ancestries. This provides tentative evidence of an anatomical etiology for chronic sinusitis even in the absence of anatomical variants/abnormalities (e.g., nasal polyps, concha bullosa, Haller's cells, and Agger nasi cells). Further research into the relationship between MS anatomy and sinusitis, in addition to socioeconomic inequalities of healthcare, is warranted to continue evaluating possible contributions to health disparities.
Morphometric and structural analysis of Florida manatee spermatozoa
Authors: Cowart Jonathan R. , Collins Danielle M. , Stanton Daniel L. , van der Horst Gerhard , Larkin Iskande V.
Published: April 2021

Sperm characteristics, such as sperm morphology and sperm morphometry are important in assessing sperm quality. This is especially important for the management and conservation of endangered and exotic species, like the Florida manatee, where information of this nature is extremely limited. In this study, we fill this knowledge gap to better understand the reproductive physiology of Florida manatees by conducting the first extensive analysis of sperm morphometry and ultrastructure. Sperm were retrieved from the vas deferens of nine recently deceased Florida manatees. Computer‐aided sperm morphology analysis (CASMA) was used for morphometric analysis and laser‐scanning confocal microscopy and electron microscopy were used for structural and ultrastructural characterization. Our findings reveal new morphometric and structural data for the Florida manatee spermatozoon. Twelve morphometric features of Florida manatee sperm were quantified with some approximately 1.5–2 times larger than those previously reported. Ultrastructurally, the Florida manatee spermatozoon followed a mammalian structural pattern with an ovate‐shaped head, midpiece containing 84–90 mitochondria, and a flagellum. However, unique ultrastructural features were identified. Distinct, rectangular‐like enlargement of four outer dense fibers surrounding the axoneme was evident, which may provide additional tensile strength to counteract the forces on sperm transiting the female reproductive tract. Likewise, strong localization of F‐actin fibers within the midpiece may function to maintain sperm integrity within the female reproductive tract. These findings highlight the potential effects of sexual selective pressures on sperm size and structure in the Florida manatee and provide avenues for research on the occurrence of sperm competition in this species.
Body Donation, Teaching, and Research in Dissection Rooms in Spain in Times of Covid‐19
Authors: Manzanares‐Céspedes Maria‐Cristina , Dalmau‐Pastor Miki , Simon de Blas Clara , Vázquez‐Osorio María Teresa
Published: April 2021

The state of alarm due to Covid‐19 pandemic in Spain stopped all educational and most university research activities. The Spanish Anatomical Society (SAE) Consensus Expert Group on Body Donations piloted a study based on a questionnaire to know the status of body donations and dissection activities during the lockdown, as well as the future implications of Covid‐19 pandemic for body donation programs and anatomy teaching. The questionnaire results show that Spanish Universities refused body donations and stopped all dissection research and teaching. The Covid‐19 expected influence on anatomy teaching was referred to the increase in teaching workforce and resources required to apply the new safety measures to future practical activities, as well as to prepare and adapt teaching material for online‐only programs. The application of reinforced safety measures was expected to be perceived by the respondent's students as a gain in teaching quality, while the transformation of the anatomy courses in online‐only programs will be perceived as a quality decrease. The respondent's concerns about future institutional implications of the pandemic were related to increased costs of the adaptation of the facilities and the reinforced preventive measures, as well as the eventual decrease in donations. The complete lockdown applied to dissection rooms was not justified by scientific evidence and represented a break of the confidence deposed in the institutions by the donors. A consensus is required for the adoption of a renewed, comprehensive protocol for present and future body donations including the evidence Covid‐19 pandemic has contributed to create.
Graphene quantum dots prepared from dried lemon leaves and microcrystalline mosaic structure
Authors: Kir Şifa , Dehri İlyas , Önal Yunus , Esen Ramazan
Published: April 2021

The aim of this study is to obtain graphene quantum dots (GQDs) by using Citrus limonum leaves grown in Adana Province, Mediterranean region. Thus, dried Citrus limonum leaves were subjected to carbonization at temperatures of 200, 275, 350, 425 and 500°C and 90, 180, and 270 min respectively at each temperature. Characterization of the material obtained at the end of the process was determined by using X‐ray diffraction (XRD), Fourier‐transform infrared (FT‐IR), fluorescence spectroscopy, elemental analyzer, scanning electron microscopy (SEM), ultraviolet (UV)‐visible, UV‐A and UV‐C lamps. It was determined that the samples obtained in the carbonization process carried out at 350 and 425°C for 3 h made blue colored fluorescence. The results of the experiments completed for characterization analysis verified the GQDs and mosaic crystal structure compared to the literature. It was observed that the GQDs obtained at 350°C for 3 h had maximum fluorescence properties. Radical changes at the sample matrix was observed when carbonization temperature changed from 350°C to 425°C.
The effect of exogenous ciliary neurotrophic factor on cell cycle and neural differentiation markers of in vitro model cells: New insights for future therapeutic approaches
Authors: Ghasemi Maryam , Alizadeh Effat , Motlagh Behzad Fallahi , Zarghami Nosratollah
Published: April 2021

Retinoblastoma is known as childhood rare malignancy of the retina. Ciliary neurotrophic factor (CNTF) was previously found to reduce degeneration and promote retina survival. This work investigated the effects of CNTF supplementation on in‐vitro model cells including retinoblastoma (Y79) and adipose‐derived mesenchymal stem cells (AMSCs) viability, proliferation, gene expression and cell cycle. A drop of viability was detected in Y79 treated with CNTF in a dose‐dependent manner (P < .05). However, the proliferation of AMSCs was increased at lower concentrations of CNTF (5 ng/mL), but declined in higher doses (50 and 100 ng/mL). The BrdU assay confirmed the MTT assay results. Cell cycle was arrested in both Y79 and AMSCs in the G0/G1 phase by CNTF treatment. A considerable down‐regulation of Bcl2, CycD1 and N‐Myc genes expression (P < .05) inversely, P15 and P21 genes up‐regulation in treated Y79 cells was observed. Besides, stemness genes' transcription was reduced in AMSCs (P < .05), and levels of neuronal‐specific markers such as neuron‐specific enolase (NSE) and neuronal nuclei (NeuN) were increased (P < .05). The findings of this study suggest a promising potential of CNTF in terms of arresting Y79 retinoblastoma cells, and differentiation‐inducing to AMSCs, which could be valuable for managing future innovative treatments targeting retinoblastoma.

Significance of the study

We demonstrate that CNTF has the potential to reduce proliferation of Y79 cells and induce the cell cycle arrest of them. Also, down‐regulation of oncogenes (such as N‐Myc) while up‐regulation of tumour suppressor genes (such as P21) was detected by exposure of Y79 cells to CNTF. Furthermore, we observed the cell cycle arrest, reduction of stemness gene and up‐regulation of neural differentiation markers in AMSCs treated with CNTF. These results support the probable promising effects of CNTF for controlling retinoblastoma.
Recent Advances in the Value Addition of Biomass‐Derived Levulinic Acid: A Review Focusing on its Chemical Reactivity Patterns
Authors: Dutta Saikat , Bhat Navya Subray
Published: April 2021

Levulinic acid (LA) is one of the most prominent biomass‐derived chemical building blocks that can be transformed into specialty chemicals like fuels, solvents, monomers for polymers, plasticizers, surfactants, agrochemicals, and pharmaceuticals. Over the past three decades, an enormous amount of research data have been acquired on the preparation and downstream value addition of LA, and these works have been reviewed. However, considering the astonishing number of publications appearing every year on LA derivatives, the periodical review of recent works focusing on unique aspects of chemistry must be undertaken to critically evaluate the achievements to date, reassess the challenges, and recognize new opportunities. This review discusses the chemical‐catalytic synthesis of various derivatives of LA by focusing on its functionalities and reactivity patterns. Recent literature on some crucial derivatives such as γ‐valerolactone, 4,4’‐diphenolic acid, and ethyl levulinate have been tabulated and discussed. The synthetic interconversion between various derivatives, mechanistic insights, critical analysis of the reaction parameters toward selective preparation of various derivatives, and their potential commercial applications have been elaborated using predominantly heterogeneous catalysts. A critical assessment of the relative advantages and shortcomings of the existing synthetic strategies for various derivatives of LA has been presented to enkindle fresh ideas.
Generation of Droplets in Double T‐Shaped Microchannels with Necked Structures
Authors: Zhang Yaolong , Chen Xueye , Han Wenbo
Published: April 2021

Microfluidic droplets are widely applied in various fields such as biomedicine, aerospace, energy utilization, and chemical engineering due to their advantages of large specific surface area, uniform size, stability, and easy control. The double T‐shaped microchannel has the characteristics of rapid preparation of microdroplets with controllable size and good uniformity. Through 3D numerical simulation, the influence of the constriction structure of the microchannel on the formation of droplets was studied qualitatively and quantitatively. Compared with ordinary double T‐shaped microchannels, the microchannels with a necked structure generate smaller droplets in diameter and faster generation frequency. Among the three structures of rectangular necking, inverted trapezoidal necking, and trapezoidal necking, the microchannel with the latter structure has the best performance, can produce monodisperse droplets of uniform size, and the period is stable.
Multi‐scale modelling of monolith reactors: A 30‐year perspective from 1990 to 2020
Authors: Hayes Robert E. , Cornejo Ivan
Published: April 2021

The honeycomb type monolith reactor dominates the field of catalytic automotive exhaust gas after treatment systems and is increasingly being used in other applications. Advanced computational modelling of such systems can provide valuable insight into their operating characteristics and be used as a design tool. This reactor provides an excellent example of a multi‐scale modelling challenge with many complexities. This paper provides a perspective on the development and use of computational modelling tools in this context over the last 30 years, with an emphasis on the work published by the researchers at the University of Alberta. This paper covers all aspects of model development, including single channel and full‐scale reactor models and inter and intra mass and heat transfer effects, with the latter including radiation.