bluuebunny/crossref_metadata_2025 huggingface dataset:
STUDY OF TEMPERATURE MEASUREMENT IN THE CUTTING ZONE USING AN ANIMATED SIMULATOR
Authors:   Chernihiv Polytechnic National University, Pasov Hennadii , Venzheha Volodymyr ,   Chernihiv Polytechnic National University, Kuzhelnyi Yaroslav ,   Chernihiv Polytechnic National University, Kolohoida Antonina ,   Chernihiv Polytechnic National University, Karpenko Oleksandr ,   Chernihiv Polytechnic National University
Published: October 2023

The temperature that occurs in the cutting zone significantly affects the wear and stability of the tool, the quality of the surface of the part and the accuracy of processing. Therefore, the study of thermal phenomena is an important task.Nowadays, the use of a simulation software product in the study of various academic disciplines is relevant.For a better understanding of the work process of various phenomena, computers and software products are used, which give the educational process a more intensive and interactive content.When performing laboratory work "Measurement of temperature in the cutting zone" it is suggested to use advanced information technologies, namely an animation simulator.The purpose of the article is to propose the use of a simulator for measuring the temperature in the cutting zone in the educational process.The “SimulatorTEMPERATURE.exe” file is launched. “Menu” appears on the screen. After getting acquainted with the main parts of the machine, they begin to set up the laboratory bench for the specified cutting modes: spindle speed, feed, cutting depth. In the process of simulating processing, indicators are removed from the device. The results are recorded in the work protocol. According to the calibration schedule, the value of the temperature at the specified processing mode is found. In the future, the machine is adjusted for other processing modes. After the end of all experiments, the results are processed and the necessary conclusions are drawn.The educational simulator, which is proposed when performing laboratory work on the study of the temperature in the cutting zone, will allow a better understanding of the process, and is also more visual.The article is a scientific and methodological publication.
International Law’s Specialised Regime and Normative Conflict: A Reflection on International Criminal Law
Authors: Linga Ahmed
Published: October 2023

In the international legal system, there exist fields of law that are characteristically specialised than the general sphere of international law. The term ‘special’, ‘specialised’ or ‘self-contained’ regime will be revisited in the present article vis-à-vis possible norms that conflict in the international legal arena. International criminal law, a discrete branch of international law will be thoroughly discussed as to reveal its nature as one of international law’s special regimes that may arguably contribute to the issue of normative conflict, and further, a problem of legal fragmentation. The concept of legal fragmentation will thus be highlighted as linked to international law’s normative conflicts. Considering that international criminal law is potentially a special regime of international law, one of its codified rules seems to have led to an emerged normative conflict involving the legal interaction between the Rome Statute of the International Criminal Court 1998’s treaty-based rule, and the international customary law rule. The severity of a legal conflict not only impacts the treaty law and customary law areas of international law but to a greater extent also undermines the coherence of the international legal system as a whole. Therefore, this article aims to analyse and expound on the apparent normative conflict of international law character that needs to be addressed, especially by the International Criminal Court being one of the prominent international judicial organs. Supposedly, when a normative conflict becomes severe, the issue of fragmentation of international law looms out and effective determination of related conflicting norms is indeed appealing.
Corruption and democracy in Brazil
Authors: Clausen Michael
Published: October 2023

Interview with Dr. Timothy Power, Professor at Oxford University about the recent chalenges of democracy in Brazil, especially regarding corruption.
Quilombonírico
Authors: Araújo Davi
Published: October 2023

Poema de Davi Araújo.
Bodenlos
Authors: Miranda Mariana Lage
Published: October 2023

Submission of five poems and two short texts for next Dossier on Brazilian Contemporary Literature.
STATE POLICY DEVELOPMENT OF UNMANNED SYSTEMS
Authors:   MIREA – Russian Technological University, Moscow, Russia, Rizaeva Yu. N.
Published: October 2023

Currently, unmanned aerial vehicles are increasingly being used in the oil and gas industry, agriculture, electric power, construction and architecture, mining, and urban economy. The number of works carried out using unmanned vehicles is increasing: aerial photography, laser scanning, gas analysis, multispectral photography and others. The organization of the functioning of unmanned logistics corridors on public roads is underway. Unmanned vehicles for technological transportation are increasingly being used in the territories of factories. The state sets a large-scale task for the specialists of the transport industry to develop unmanned transport. In order to conduct research in this area, it is necessary to clearly trace the main guidelines of state policy in the field of unmanned transport, to represent the field of development of the transport industry. The article analyzes the state policy aimed at the development and maintenance of unmanned systems in the aviation, railway, and automotive industries. The regulatory and legislative framework regulating the possibility of creating and operating unmanned vehicles in the Russian Federation is given. One of the problems of the use of drones is the lack of legal regulation of their use in the transport complex of the country. Currently, programs and documents regulating the development of unmanned systems are being implemented and planned for implementation at the state level: “Strategy for the development of unmanned aviation of the Russian Federation for the period up to 2030 and for the future up to 2035”, “Transport Strategy of the Russian Federation up to 2030 with a forecast for the period up to 2035”, Decree of the Government of the Russian Federation “On the establishment of an experimental Legal Regime in the Field of digital innovations and Approval of the Program of an experimental legal Regime in the Field of Digital innovations for the Operation of Highly Automated Vehicles in relation to the implementation of the initiative “Unmanned Logistics Corridors” on the Federal Highway M-11 “Neva”, etc. For the possibility of using unmanned vehicles in the Russian Federation, interdepartmental interaction of federal executive authorities is necessary. The state policy in the field of creation, production and operation of unmanned systems is aimed, among other things, at the development of human resources, training of specialists with interdisciplinary knowledge.
A. F. Losev on the Neoplatonic Essence of Music in the Context of the Philosophy of Substantial Musical Existence (to the 130th Anniversary of the Birth of Aleksey Fedorovich Losev)
Authors:   Orenburg State University, Orenburg, Russia, Kolomiets G. G.
Published: October 2023

The article is written in connection with the anniversaries of the life of the great Russian thinker Alexey Fedorovich Losev and is devoted to one of the aspects of his aesthetic research related to the interpretation of music in Neoplatonism. This article makes sense to emphasize the substantial ontological essence of music, relying on Losev’s phenomenological-dialectical method, on his commitment to Neoplatonism as the last significant ancient philosophical movement. Losev considered the philosophical foundations of music in the cosmological treatises of such philosophers as Quintilian, Proclus, Sallust. Touching upon the ancient origins of the philosophy of music as an aesthetic field, the author refers to the Pythagorean teaching of the divine number and the musical harmony of the spheres. At the same time, Neoplatonic ancient philosophy demonstrates different types of existence of music, or ancient Greek music. The combination of the logical and the illogical in Losev’s philosophical thinking allows the author to present through the prism of the philosophy of substantial musical existence the closeness of the idea of the existence of the music of the Neoplatonists, proceeding from the ideas of the One, and Losev, the divine unity, where the thought of music goes far beyond the limits of the actual musical art. Music in philosophical knowledge is outside of art as world harmony, substance, becoming in time, divine number, or the life of numbers, the expression of the numerical first principle. In the sources, the author used the works of A. F. Losev: “The History of ancient Aesthetics”, “Dialectics of myth”, “Dialectical foundations of mathematics”, which presents a deep connection between mathematics and music. At the same time, the author relied on his aesthetic research “The Logos of music in the phenomenological-dialectical method of A. F. Losev”, and other chapters of his book “The Value of Music: a philosophical aspect” and his dissertation “The concept of the value of music as a substance and a way of value interaction of a person with the world”. Summarizing, the author moves from the dialectic of musical-substantial being to the philosophical concept of “musical” as an aesthetic category that requires further research.
Сurrent problems in the application of the software «System Portal Seaport» and prospects for its improvement in order to ensure the safety of trade
Authors:   JSC “Eurosim Travel”, Riga, Latvia, Podlesny I.
Published: October 2023

The relevance of this article is dictated by the need to study ways to improve the efficiency of trade through the introduction of innovative systems of customs management and control. The purpose of the study is to analyze the experience of using the Portal Seaport software package, taking into account its external and internal problems, including the interaction of various participants in maritime transportation. In methodological terms, the author is guided by the basic principles of a systematic approach. The main result of the study is that the author formulates a set of principles, formulated taking into account the recommendations of the United Nations, with the aim of contributing to the facilitation of international trade procedures and increasing the level of resistance to security threats. The scientific novelty of the article is manifested in the fact that the text of the article explores the system of preliminary informing the customs authorities during the delivery of goods by sea, little studied in the domestic specialized literature. Accordingly, the practical significance of the article lies in the development of the author’s recommendations that can be used to more effectively modernize the relevant mechanisms for managing and controlling foreign trade activities. The direction of the author’s further research can be formulated in the following way. The Seaport Portal system needs to be improved, so it is necessary to focus on the benefits that traders will receive if the imperfections of this system are eliminated, and to comprehensively explore ways to achieve qualitatively different results. The author’s recommendation is not only to comprehensively study the systems of preliminary information, but also to expand the scope of their implementation in the state control system.
Method of in-depth diagnostics of the main brake cylinder of a motor vehicle
Authors:   Kurgan State University, Kurgan, Russia, Borodin A. L. , Vasiliev V. I. ,   Kurgan State University, Kurgan, Russia, Shaburov V. N. ,   Kurgan State University, Kurgan, Russia
Published: October 2023

The use of new methods for element-by-element diagnostics of the brake system increases the probability of detecting malfunctions, helps to identify faulty elements in the nodes of the brake system in advance, which helps to reduce accidents on the roads of the country. The development of a method for in-depth diagnosis of the master brake cylinder is an urgent task. Earlier, as part of the development of a new method for diagnosing the main brake cylinder of a hydraulic brake system, a set of diagnostic parameters was determined by the dynamic parameters of the resistance force to pressing the brake pedal. The need to introduce the method for practical use at road transport enterprises set the authors the task of determining the maximum permissible values of diagnostic parameters based on the comparison results, with which a conclusion will be made about the technical condition of the object with subsequent diagnosis. The aim of the work is to determine the maximum allowable values of diagnostic parameters, and to develop an algorithm for making a diagnosis. The maximum permissible values of the diagnostic parameters of the main brake cylinder were determined on the basis of a statistical method. The main provisions of the method are that a one-time sample of N values of the diagnostic parameter was considered for representatives of the set of diagnostic objects (both serviceable and faulty). At the same time, it was assumed that the values corresponding to the serviceable state would obey a different pattern than the values corresponding to the faulty one. Having singled out the distribution function f(S) of the parameter values for the healthy state of the object from the total population, the range of acceptable values of the diagnostic parameter in operation can be limited by some limiting dispersion relative to the nominal (reference) value of the parameter. For the braking system affecting traffic safety, the restriction was applied with 85% probability. The values were found for the entire range of diagnostic parameters. In the course of the study, the maximum permissible values of diagnostic parameters were determined. A diagnostic matrix of the main brake cylinder has been built. An algorithm for making a diagnosis has been developed. The scientific novelty lies in the difference in their implementation in the range of service braking, which makes it possible to maximize the informative possibility of each of the diagnostic parameters.
Factors of increasing engine oil replacement time in automobile diesel engines
Authors:   FSUE ", Nazarov F. L. ,   NAMI",   , Moscow,   Orenburg State University, Orenburg, Russia
Published: October 2023

The relevance of the research topic is due to the fact that the potential for increasing the replacement period of engine oil in modern and promising automotive engines should have not only a marketing basis, but also a scientific justification for its implementation. The aim of the study is to reduce the unit cost of maintenance of automobile engines by increasing the timing of engine oil change. A particular task within the framework of this article is to establish the factors that cause an increase in the period for replacing engine oil in automobile diesel engines (on the example of the KAMAZ R6 family). The methodological apparatus for solving this problem was based on an in-depth analysis of previously obtained results of experimental studies of the patterns of «aging» of motor oils in diesel engines of the KAMAZ V8 family, depending on various factors in conjunction with the criterion of «rigidity» of the engine oil. For the first time, a quantitative assessment of the influence of the identified factors on the increase in the oil change period is given (ceteris paribus): – the use of oils of higher classes in terms of performance – for example, the transition from CD to CF-4 / SG according to API – by 4,4 times; – reduction of sulfur content in fuel - for example, for the API CG-4 class with a decrease from 0,05% to 0,035% – by 2,6 times, for the API CI-4 class with a decrease from 0,035% to 0,001% – in 2,3 times; – reduction of the criterion of «rigidity» of oil operation A – for example, for API CF-4 / SG class with a decrease (in terms of engine power) from A = 770 to A = 550 – 4 times; for the API CI-4/CG-4 class with a decrease (in terms of oil sump capacity) from A = 1176 to A = 835 – by 2,8 times, and to A = 640 – by 3,1 times. The basic requirements for engine oil of engines of the KAMAZ R6 family are formulated. The selected oils of two brands provided a test-confirmed increase to 150 thousand km. replacement period, and therefore were approved for use by the manufacturer of KAMAZ PJSC. The theoretical value for the development of the branch of science «Operation of road transport» lies in the fact that the identified factors and patterns contribute to the study of the efficiency, quality, characteristics, performance indicators of automotive operating materials. The author sees further research based on this work in a formalized assessment of the influence of the factors under consideration on the period of replacement of engine oil.
DEVELOPMENT OF PROBIOTIC SUPPLEMENTS FOR THE PREVENTION OF ATHEROSCLEROSIS
Authors:   Kemerovo State University, Vesnina A.D. , Prosekov A.Yu.
Published: October 2023

Proper (rational, balanced) nutrition is a relatively simple, affordable preventive measure. Thanks to the modern development of science and technology, the concept of “proper nutrition” includes a personalized approach, i. e. can be formed taking into account the individual characteristics of the consumer. This work is aimed at developing the composition of individually selected functional food supplements based on probiotics.
TECHNOLOGY OF ENCAPSULATION OF PROBIOTIC MICROORGANISMS FOR THE PRODUCTION OF FUNCTIONAL FOODS
Authors:   Emanuel Institute of Biochemical Physics RAS, Moscow, Galimova A.R. , Kanochkina M.S. ,   Russian Biotechnological University, Moscow
Published: October 2023

An analysis of technologies for encapsulating probiotic microorganisms with biopolymers based on sodium alginate was carried out. Such microencapsulation is necessary to protect probiotics during processing, storage, and their targeted delivery to the colon.
STUDY OF THE INFLUENCE OF UV IRRADIATION TIME ON THE FUNCTIONALITY OF CARBOXY GROUPS OF “POLYMER BRUSHES”
Authors:   Engelhardt Institute of Molecular Biology RAS, Moscow, Detkov G.M. , Zasedateleva O.A. , Vasiliskov V.A. , Chudinov A.V.
Published: October 2023

A chemical modification of a polypropylene substrate by grafting “brush polymers” by photoinduced lithographic polymerization was performed. The dependence of the signal intensity of a covalently bound fluorescent dye with the functional groups of “polymer brushes” on the ultraviolet light irradiation time was determined.
OBTAINING MRNA ENCODING HEMAGGLUTININ OF INFLUENZA A VIRUS SUBTYPE H7N9 BY IN VITRO TRANSCRIPTION AND EVALUATION OF THE EFFICIENCY OF TRANSLATION OF THE OBTAINED MRNA IN THE EUKARYOTIC CELL LINE A549
Authors:   Smorodintsev Research Institute of Influenza, Saint Petersburg, Dobrovolskaya O.A. , Elpaeva E.A. , Vysochinskaya V.V. ,   Peter the Great Saint Petersburg Polytechnic University
Published: October 2023

RNA-based vaccines are the newest promising alternative to traditional approaches to treat viral diseases. In this study, we obtained mRNA encoding the hemagglutinin of influenza A subtype H7N9 by in vitro transcription and evaluated the efficiency of its translation on the A549 cell line. It was shown that mRNA is efficiently delivered and translated in vitro and can be successfully used for further experiments in vivo.
ALLOSTERIC REGULATION OF CRISPR/CAS9 SYSTEM ON THE RNA LEVEL
Authors:   1 Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Dolzhikova O.A. , Semikolenova O.A. , Meschaninova M.I. , Novopashina D.S. ,   Novosibirsk State University
Published: October 2023

CRISPR/Cas9 systems are commonly used for the introduction of double-strand break at the targeted point of DNA. A possible way to improve its specificity is allosteric regulation. Here, we designed guide RNA containing theophylline-binding or Mango aptamer and investigated their functional activity by the example of the model DNA cleavage either in absence or in presence of theophylline or thiazole orange respectively.
EFFECT OF SURFACTANTS ON THE CHARACTERISTICS OF POLY(3-HYDROXYBUTYRATE) AND POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE) NANOPARTICLES
Authors:   Siberian Federal University, Krasnoyarsk, Dorokhin A.S. , Lipaikin S.Yu.
Published: October 2023

In this work, the effect of six non-ionic and two anionic surfactants on the characteristics of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nanoparticles obtained by single emulsion solvent evaporation technique was assessed. The most satisfactory results were obtained when polyvinyl alcohols with relatively low molecular weight were used as a surfactant.
ANTIRADICAL AND ANTIOXIDANT ACTIVITY OF PHLOJODICARPUS SIBIRICUS
Authors:   Ammosov North-Eastern Federal University, Yakutsk, Egorov A.N. , Voronov I.V. , Troev I.P. , Gotovtsev1 R.A. ,   Institute for Biological Problems of Cryolithozone SB RAS, Yakutsk
Published: October 2023

The effectiveness of the antiradical and antioxidant action of extracts obtained from the Siberian puffball (lat. Phlojodicarpus sibiricus) was studied. As a result of comparing the antiradical and antioxidant activity of extracts depending on the concentration of the extractant, the highest efficiency of quenching radicals with 40 % water-ethanol extracts was established in comparison with commercial extracts of Rhodiola rosea and ginseng roots.
BACTERIAL DIVERSITY OF OILFIELD WATERS OF THE REPUBLIC OF TATARSTAN
Authors:   Kazan Federal University, Ziganshina E.E. , Ziganshin A.M.
Published: October 2023

Oilfield waters are characterized by distinct microbial communities due to several environmental factors. In this work, the bacterial diversity of oilfield water samples of the Republic of Tatarstan (Russia) was analyzed. The objects of research were bacterial cultures from formation and injection waters. The bacterial communities in oilfield waters were represented by members of the phyla Firmicutes, Proteobacteria and Actinobacteria.
PRODUCTIVITY OF CHLORELLA DURING GROWTH IN DOMESTIC WASTEWATER
Authors:   Kazan Federal University, Ziganshina E.E. , Bulynina S.S. , Ziganshin A.M.
Published: October 2023

Uncovering the structure of bacterial communities in wastewater, which is an alternative growth medium for microalgae, is necessary to improve the quality of algal products. The results of the work indicate the sustainability of the growth of Chlorella sorokiniana in distinct non-sterile domestic wastewaters, both in terms of bioremediation and the production of valuable products.
RECOMBINANT MONOCLONAL ANTIBODIES WITH VIRUS NEUTRALIZING ACTIVITY AGAINST SARS-COV-2 DELTA AND OMICRON VARIANTS
Authors:   State Research Center of Virology and Biotechnology VECTOR, Koltsovo, Zimonina A.A. , Prudnikova E.Yu. , Imatdinov A.R.
Published: October 2023

The study describes the production and characterization of recombinant human monoclonal antibodies interacting with the receptor-binding domain of the Spike glycoprotein and possessing virus-neutralizing activity against SARS-CoV-2 variants Delta and Omicron.
ZNFE2 O4 @MNFE2 O4 MAGNETIC NANOPARTICLES AS A PROMISING CARRIER FOR LIPASE IMMOBILIZATION
Authors:   SCAMT Institute, ITMO University, Saint Petersburg, Ionov Y.A. , Shabalkin I.D. , Nazarova E.A.
Published: October 2023

In the field of development of highly efficient biocatalysts, more modern methods of their production are required, for example, the selection of new carriers for enzymes. The carrier can provide resistance to various effects on the biomolecule or change the conditions of the reaction. The thesis considers a method of enzyme immobilization on modified magnetic nanoparticles capable of heating the medium under the influence of electromagnetic radiation.
EFFECT OF PEDOT:PSS-BSA MATRIX ON THE RESPIRATORY ACTIVITY OF MICROBIAL CELLS AND THEIR MEMBRANE FRACTIONS
Authors:   Tula State University, Kadison K.V. , Bykov A.G. , Arlyapov V.A. , Reshetilov A.N. ,   Skryabin Institute of Biochemistry and Physiology of Microorganisms RAS, Pushchino
Published: October 2023

We studied the changes of respiratory activity of G. oxydans VKM B-1280 cells and their membrane fractions toward glucose and ethanol under the action of PEDOT:PSS (poly(3,4-ethylenedioxythiophene):(polysterenesulfonic acid)) and BSA (bovine serum albumin).
Studi Evaluasi Dan Perencanaan Eksisting Kinerja Proses Pengolahan Air Minum Instalasi Pengolahan Air Arang Limbung Perumda Air Minum Tirta Raya Kabupaten Kubu Raya
Authors: Aulia Sauqiyah , Kadaria Ulli , Nugraheni Putranty Widha
Published: October 2023

Lokasi penelitian berada di IPA 3 Perumda Arang Limbung, Desa Arang Limbung, Kecamatan Sungai Raya, Kabupaten Kubu Raya. Memiliki kapasitas 120 L/detik serta unit pengolahan pengolahan lengkap. Air baku menggunkan  air Sungai Kapuas dan hasil pengamatan didapatkan kerak dan lumut menempel di dinding bak yang bisa mempengaruhi kualitas dan kuantitas air. Tujuan penelitian ini untuk mengetahui kualitas air baku dan air hasil olahan IPA 3 Arang Limbung apakah sesuai standar baku mutu serta memberikan rekomendasi optimalisasi IPA pada unit proses. Tahapan penelitian meliputi analisa kualitas air baku, evaluasi kondisi eksisting instalasi dan optimalisasi kinerja unit operasi dan proses pengolahan instalasi, analisa kualitas air produksi dan hasil optimalisasi unit instalasi. Kualitas air baku tidak sesuai baku mutu air kelas I PP RI No. 22 Tahun 2021 yaitu kekeruhan 42,237 NTU, warna 323,333. Kualitas air minum tidak sesuai dengan Kepmenkes RI No. 492/Menkes/Per/IV/2010 yaitu warna 125 Pt.Co, dan pH 4,56. Upaya optimalisasi IPA 3 Arang Limbung yaitu, dilakukan penentuan dosis koagulan dengan percobaan jartest, mendesain ulang beberapa unit operasi instalasi antara lain, bak flokulasi yaitu P = 5 m, T = 5 m, bak sedimentasi P = 14 m, L = 6 m, bak filtrasi P = 8 m, L = 4 m, H = 5,5 m, dan menambah satu unit bak reservoir. Diharapkan dengan dilakukannya evaluasi pada IPA 3 Arang Limbung hasil air olahan sesuai dengan baku mutu Permenkes No.492 Tahun 2010 dan perencanaan unit instalasi pengolahan sesuai dengan SNI 6774-2008.
Daftar Isi
Authors: Engineering Environmental
Published: October 2023

Daftar Isi
Tryptophan Molecular Moiré Superlattices with Visible Fluorescence
Authors: Dey Ujjala , Chattopadhyay Arun
Published: October 2023

Moiré superlattices of molecules may give birth to a new field of chemistry. For example, when crystalline nanoscale 2D sheets of a molecule are stacked with lattice planes twisted at low angles of each other, the interactions at the interfaces - that differs from the supramolecular interactions within the crystalline nanosheet and can be termed as hypermolecular interactions - may bring about new physical and chemical properties. Herein, we report for the first time the chemical synthesis of moiré superlattices of L or D tryptophan (trp) molecules formed in situ through twisted stacking of trp crystalline nanosheets. Transmission emission microscopy (TEM) measurements supported the formation of moiré superlattices of the crystalline 2D nanosheets. The resulting films were stable under alkaline conditions and exhibited strong photoluminescence emission peak at 452 nm and an additional peak at 500 nm due to the formation of a new energy state.
A high macro molecular ghost in SEC analysis of conjugate polymer
Authors: Mori Atsunori , Yamaoka Seiha , Okano Kentaro
Published: October 2023

SEC (size exclusion chromatography) analyses of conjugated polymers (polythiophene and polyphenylene) were carried out. When a semimicro analytical column was employed for the measurement of the molecular weight, an extremely large molecular weight peak (>100000 Da) was observed. Preparative SEC of each fraction and the further analysis revealed that such a high-molecular-weight peak was only found in the analysis with a semimicro column and found that the ghost peak was derived from low-molecular-weight fraction (M < 4000), which would form aggregation to higher molecular weight of earlier eluate in SEC.
Unraveling the Internal Structure of 3D Printed Stimuli-Responsive Materials Using a Molecular Probe
Authors: Kang Xiaowo , Wu Weijun , Hu Yu , Liu Xindi , Wang Wenhui , Song Qiao , Xiong Yu , Bao Yinyin , Zhang Lu , Zhao Bin , Jiang Hongyan , Yao Mingxi , Luo Zhi
Published: October 2023

Stimuli-responsive 3D printing, or 4D printing, offers unparalleled potential in various research fields, enabling the combination of complicated mechanical design with programmable functionalities. The switchable polymer network structures, e.g., crystalline domains, free volume, and phase separation, are the key to achieving macroscopic responsiveness. However, despite a growing repertoire of new materials, most studies rely on rudimentary imaging techniques to visualize the materials’ shape change under external stimuli. Seldomly could such macroscopic behavior be correlated with the nanoscopic structures and dynamics of polymers. Here, leveraging the AIE phenomena, we introduce a novel method that can offer direct insights into the network structures and the chain mobility of the printed polymers. We developed a new photo-polymerizable polyurethane with multiple responsive characteristics, including temperature, mechanical strain, and pH, as an example of 4D printing materials. By embedding AIEgen in the polymer matrix, we demonstrated that the emission intensity and wavelength can serve as reporters and correlate the intramolecular motions of the AIEgen with the stimuli-responsive properties of the polymers. These observations were confirmed by small-angle X-ray scattering revealing the underpinning structural evolution. With potential applications for real-time structural monitoring, this study provides a new tool for the characterization of 4D printed materials.
NHC-CDI ligands boost multicarbon production on Cu electrocatalysts by increasing the accumulated surface charge and promoting *CO dimerization
Authors: Kolding Kirstine Nygaard , Bretlau Matias , Zhao Siqi , Torbensen Kristian , Daasbjerg Kim , Rosas-Hernández Alonso
Published: October 2023

Copper-based materials have shown significant potential as catalysts for the electrochemical CO2 reduction reaction (CO2RR) due to their inherent ability to produce multicarbon products. The functionalization of Cu electrodes with organic additives represents a simple yet powerful strategy for improving the intrinsic activity of these electrocatalysts by tailoring the microenvironment around the Cu active sites to favor specific reaction pathways. In this work, we introduce NHC-CDI-functionalized Cu catalysts, which demonstrate a remarkable increase in activity for multicarbon product formation, surpassing bare Cu electrodes by more than an order of magnitude. These hybrid catalysts operate efficiently in a gas diffusion configuration, achieving a multicarbon product selectivity of 58% with a partial current density of −80 mA/cm2. Using modified pulsed voltammetry measurements, we found that the activity for multicarbon product formation is closely linked to the surface charge that accumulates during electrocatalysis, resulting from the buildup of CO2RR intermediates. We further supported our findings with in situ Raman spectroscopy measurements, which unveiled a preference for car- bon monoxide binding on Cu step sites, which are known to promote C─C coupling, in the best-performing hybrid catalysts. Additionally, we observed a general preference for atop- bound *CO intermediates over bridge-bound ones in the molecularly functionalized catalysts. Our study underscores the significant potential of molecular tuning in developing efficient electrocatalysts for CO2 reduction and emphasizes the utility of surface charge as a descriptor of multicarbon product activity.
Development of a Biocatalytic Aerobic Oxidation for the Manufacturing Route to Islatravir
Authors: Shaw Megan H. , Fryszkowska Anna , Alvizo Oscar , Attadgie Ilana , Borra-Garske Margie , Devine Paul N. , Duan Da , Forstater Jacob H. , Grosser Shane T. , Hughes Gregory J. , Maloney Kevin M. , Margelefsky Eric L. , Mattern Keith A. , Miller Margaret T. , Nawrat Christopher C. , Nazor Jovana , Orth Peter , Ouimet Claire M. , Robaire Sandra A. , Ruccolo Serge , Schwalm Erica L. , Verma Deeptak , Xiao Li , Zhang Victoria
Published: October 2023

Biocatalytic oxidations have the potential to address many synthetic chemistry challenges, enabling the selective synthesis of chiral intermediates such as carbonyl compounds, alcohols, or amines. The use of oxygen-dependent enzymes can dramatically reduce the environmental footprint of redox transformations at manufacturing scale. Here, as part of the biocatalytic cascade to an anti-HIV investigational drug islatravir 1, we describe the development of an aerobic oxidation process delivering (R)-ethynylglyceraldehyde 3-phosphate 3 using an evolved galactose oxidase enzyme. Integrated enzyme and reaction engineering were critical for achieving a robust, high-yielding oxidation performed at pilot plant scale (>20 kg, 90% yield).
Green Synthesis of Sulfur-Containing Polymers by Carbon Disulfide-based Spontaneous Multicomponent Polymerization
Authors: Chen Xu , Qin Anjun , Tang Ben Zhong
Published: October 2023

Sulfur-containing polymers have gained much attention in polymer science due to their unique properties. Nevertheless, their preparation has posed considerable challenges, particularly in diversifying their structures and achieving highly efficient polymerizations. This is especially true for the polymers derived from CS2, a readily available one-carbon (C1) feedstock, as their synthesis often necessitates harsh conditions or results in unexpected byproducts. In this work, we established a regio-selective and atom-economy spontaneous multicomponent polymerization based on carbonyl or ester group-activated internal alkynes, commercially available amines, and CS2. Similar to the angled half lap joint of two plates in a scarf joint of in ancient Chinese tenon and mortise architecture, these internal ethynyl and amino groups can not readily react at room temperature. However, the addition of CS2 acts as a "wedge," making the polymerization spontaneous and enabling the tight linkage and extension of these functional groups into stable polymer chains. The sulfur-containing polymers with satisfactory weight-average molecular weights (up to 31 600) were produced in high yields (up to 97%). The resultant polymers exhibit exceptional characteristics, including high refractive indices (up to 1.7471 at 632.8 nm), excellent light transmittance, and good film-forming capabilities. This work opens up a new avenue for the green and efficient synthesis of functional sulfur-containing polymers, using cost-effective CS2 as starting material.
Vitamin B12–Photocatalyzed Cyclopropanation of Electron-Deficient Alkenes using Dichloromethane as the Methylene Source
Authors: Teye-Kau John Hayford , Ayodele Mayokun , Pitre Spencer
Published: October 2023

The cyclopropyl group is of great importance in medicinal chemistry, as it can be leveraged to influence a range of pharmaceutical properties in drug molecules. This report describes a Vitamin B12-photocatalyzed approach for the cyclopropanation of Michael acceptors using CH2Cl2 as the methylene source. The reaction proceeds in good to excellent yields under mild conditions, has excellent functional group compatibility, and is highly regioselective. The scope could also be extended to the preparation of D2-cyclopropyl and methyl-substituted cyclopropyl adducts starting from CD2Cl2 and 1,1-dichloroethane, respectively.
Molecular insights into the formation of drug-polymer inclusion complex
Authors: Lu Ming , Liu Binbin , Li Changrui , Chen Ziqiao , Ou Xiao , Li Shuting , Li Ao , Chen Pin
Published: October 2023

Drug-polymer inclusion complex (IC) has been viewed as a novel solid form of drugs for property modification. Nonetheless, our understanding of the formation mechanism remains limited. This work aims to provide insight into the molecular processes governing the structural construction of carbamazepine (CBZ) and griseofulvin (GSF) channel-type ICs in the presence of guest polymers. Leveraging microdroplet melt crystallization, we successfully unveiled the single-crystal structures of these ICs, enabling theoretical analysis. Our investigation, which encompasses structural analysis, density functional theory calculations, and molecular dynamics (MD) simulations, elucidates the disparity between CBZ and GSF channels in terms of their autonomy in the absence of guest polymers. CBZ molecules can spontaneously assemble into stable channel structures independently, capitalizing on their unique mortise-tenon architecture and robust π...π interactions. In contrast, GSF channels lack sufficient support from weak Cl...O and C-H...π intermolecular interactions and necessitate the insertion of guest molecules to stabilize their structures. Regardless of the structural reliance on guest polymers, channel size is determined by the size, shape, and conformation of the host molecules, as well as intermolecular interactions. Interestingly, while the eleven structurally determined drug-polymer ICs adopt diverse approaches to construct channel structures, their channel sizes consistently fall within a narrow range of 3.86-5.18 Å, slightly larger than the radial diameter of the guest polymers (2.83-3.50 Å). Consequently, we propose that a crucial prerequisite for the formation of drug-polymer ICs is that the host molecules have the capacity to self-assemble into a porous structure with accommodating channels for guest polymers. Additionally, our results confirm the efficacy of microdroplet melt crystallization in rapidly synthesizing drug-polymer ICs and cultivating their single crystals of high quality and sufficient size. This achievement overcomes the challenges associated with structure elucidation and promises to promote further research into the formation mechanism of drug-polymer ICs. We anticipate that these findings will inspire continued exploration of this novel solid form, facilitating theoretical predictions and practical applications in pharmaceutical development.
Surface Defect Healing in Annealing from Nanoporous Carbons to Nanoporous Graphenes
Authors: Yamazaki Kaoru , Goto Shunsuke , Yoshino Shunya , Gubarevich Anna , Yoshida Katsumi , Kato Hideki , Yamamoto Masanori
Published: October 2023

Nanoporous graphene (NPG) materials have the pronounced electrochemical stability of the seamless graphene structures developed over the 3D space. We revisited the Raman spectra of nanoporous carbons (NPCs) synthesized using θ-/γ-Al2O3 templates and NPGs converted from NPCs by annealing at 1800 ºC to identify the type and density of defects. We found that both the NPCs and NPGs mostly consist of single-layered graphene with a few single vacancies and Stone‒Wales defects. The density of vacancy defect per hexagon in the graphene sheet is estimated to be 10-2 for NPCs, while the annealing reduced the value to 10-3‒10-4 for NPGs. This supports the outstanding chemical and electrochemical stability of the novel porous carbon materials.
Utilization of AlphaFold Models for Drug Discovery: Feasibility and Challenges. Histone Deacetylase 11 as a Case Study
Authors: Baselious Fady , Robaa Dina , Sippl Wolfgang
Published: October 2023

Histone deacetylase 11 (HDAC11), an enzyme that is cleaving acyl groups from acylated lysine residues, is the sole member of class IV of HDAC family with no reported crystal structure so far. The catalytic domain of HDAC11 shares low sequence identity with other HDAC isoforms which complicates the conventional template based homology modeling. AlphaFold is a neural network machine learning approach for predicting the 3D structures of proteins with atomic accuracy even in absence of similar structures. However, the structures predicted by AlphaFold are missing small molecules as ligands and cofactors. In our study, we first optimized the HDAC11 AlphaFold model by adding the catalytic zinc ion followed by assessment of the usability of the model by docking of the selective inhibitor FT895. Minimization of the optimized model in presence of transplanted inhibitors, previously described as HDAC11 inhibitors for which X-ray structures with the related HDAC8 are available was performed. Four complexes were generated and proved to be stable using three replicas of 50 ns MD simulations and were successfully utilized for docking of the selective inhibitors FT895 and MIR002 and SIS17 The most reasonable pose was selected based on structural comparison between HDAC6, HDAC8 and the HDAC11 optimized AlphaFold model. The manually optimized HDAC11 model is thus able to explain the binding behavior of known HDAC11 inhibitors and can be used for further structure based optimization.
Characterization of binding profiles of heparanase with existing small-molecule inhibitors using computational methods
Authors: Zhang Yuzhao , Cui Lina
Published: October 2023

Heparanase (HPSE) is an emerging therapeutic target involved in various diseases. The primary function of the glycosyl hydrolase is to cleave heparan sulfate (HS) side chains from heparan sulfate proteoglycans (HSPGs). This process regulates the homeostasis and the integrity of the extracellular matrix (ECM) and the bioavailability of growth factors and cytokines. Overexpression of heparanase has been observed under various pathological conditions, such as cancer, angiogenesis, and inflammation, suggesting HPSE a promising therapeutic target. However, despite decades of research on HPSE inhibitors, no small-molecule HSPE inhibitor has been approved by regulatory agencies. In this study, we used computational tools to provide insights into small-molecule HPSE inhibitors design. We performed a series of molecular dynamics (MD) simulations and binding profile analyses of 48 diverse small-molecule HPSE inhibitors reported by various research labs. Our results identified the key binding residues on HPSE that should be targeted in inhibitor design, considering both their importance in facilitating interactions with the inhibitor and their functional roles. We also performed energy analyses to create a binding energy map showing the energy breakdown on HPSE residues. To guide future HPSE small-molecule inhibitor discovery, we built a pharmacophore model based on key binding features identified in this study. We also selected and discussed good binding modes discovered through MD. Our findings provide insight into the design and development of small-molecule-based HPSE inhibitors.
Paramagnetic NMR Shifts for Triplet Systems and Beyond with Modern Relativistic Density Functional Methods
Authors: Franzke Yannick J. , Bruder Florian , Gillhuber Sebastian , Holzer Christof , Weigend Florian
Published: October 2023

An efficient framework for the calculation of paramagnetic NMR (pNMR) shifts within exact two-component (X2C) theory and (current-dependent) density functional theory (DFT) up to the class of local hybrid functionals is presented. Generally, pNMR shifts for systems with more than one unpaired electron depend on the orbital shielding contribution and a temperature-dependent term. The latter includes the zero-field splitting, the hyperfine coupling, and the g- tensor. For consistency, we calculate these three tensors at the same level of theory, i.e. using scalar-relativistic X2C augmented with spin–orbit perturbation theory. Results for pNMR chemical shifts of transition-metal complexes reveal that this X2C-DFT framework can yield good results for both the shifts and the individual tensor contributions of metallocenes and related systems, especially if the hyperfine coupling (HFC) constant is large. For small HFC constants, the relative error is often large and sometimes the sign may be off. 4d and 5d complexes with more complicated structures demonstrate the limitations of a fully DFT-based approach. Additionally, a Co-based complex with very large zero-field splitting and pronounced multireference character is not well described. Here, a hybrid DFT-multireference framework is necessary for accurate results. Our results show that X2C is sufficient to describe relativistic effects and computationally cheaper than a fully relativistic approach. Thus, it allows to use large basis sets for converged hyperfine couplings. Overall, current-dependent meta-generalized gradient approximations (meta-GGAs) and local hybrid functionals show some potential, however, the currently available functionals leave a lot to be desired.
Structural Investigation of the Cu/W/Co-based Mixed Metal Oxide Electrocatalyst using X-ray absorption Spectroscopy.
Authors: Gupta Nikita , Segre Carlo , Streb Carsten , Gao Dandan , Glusac Ksenija
Published: October 2023

Mixed metal oxide is an attractive electrocatalyst class for efficient water splitting, yet the identification of real active sites and understanding of synergistic effects are still insufficient. Here, we applied in situ synchrotron-based X-ray absorption spectro-electrochemistry (XAS-EC) to explore the bifunctional mixed Co-Cu-W oxide interface under electrocatalytic conditions. Our investigation, including X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), elucidated the dynamic structural transformations of Co, Cu, and W during the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Ex situ XAS measurements indicate the local chemistry of the focused metal centers. The subsequent XAS-EC XANES and EXAFS measurements shed light on the chemical and structural evolution of the Co-Cu-W oxide, in which Co and Cu actively participate in OER and HER while W plays a crucial role as structure stabilizer. This approach provides a valuable means of revealing the complex catalytic mechanism of significantly emerging mixed metal oxide electrocatalysts for advanced water splitting.
The Mediating Role of Country of Origin Effect in the Effect of Consumer Ethnocentrism on Café Preference
Authors: BİLGİN TURNA Gülçin
Published: October 2023

This research aims to investigate the mediating role of the country of origin effect (COO) in the relationship between consumer ethnocentrism (CE) and cafe preference. Consumer ethnocentrism refers to the extent to which consumers exhibit a preference for domestic products over foreign ones. The country of origin effect suggests that consumers’ evaluations and perceptions of a product are influenced by its country of origin. In the context of the cafe industry, this study examines whether consumer ethnocentrism influences Turkish/American cafe preference, and whether this relationship is mediated by the country of origin effect for Turkish consumers who live in Rize. The findings revealed that CE has an effect on both COO and cafe preference. COO has a direct effect on cafe preference and mediation role in the effect of consumer ethnocentrism on cafe preference. The result indicating that the country of origin effect of Turkish consumers has a positive impact on both Turkish and American cafe preferences suggests that Turkish consumers may have a favorable view of both Turkish and American cafes based on their perceived country of origin.