bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of COVID-19 on the Introduction of Digital Technologies by International Business
Authors:   V. N. Karazin Kharkiv National University, Shkodinа I. V. , Serdyuk T. V. ,   V. N. Karazin Kharkiv National University
Published: December 2020

The article is aimed at analyzing the peculiarities of the introduction of digital technologies by the international business in the conditions of COVID-19. Based on the analysis of the impact of COVID-19 on the introduction of digital technologies by the international business, the authors concluded that the crisis, on the one hand, slowed down the financing of some investment projects, but, on the other hand, it stimulated the implementation of projects related to the digitalization of international business (5G, start-up factories, the Internet of Things, robotics and blockchain). There was an increase in financing for projects related to remote work, virtual cooperation instruments, mobile devices, security programs. In the long term, COVID-19 will exacerbate the problem of digital gap between both countries and businesses and among the population. It is concluded that the Big Tech’s digital innovations increase the profitability of tech giants, and flows of cheap liquidity (as a means of countering COVID-19) lead to the formation of a new bubble in the market (P/E is close to 75). After the pandemic, traditional business will resume, but the digital gap will increase and remain a major economic and social problem. To solve these problems, it is imperative to improve the State-based regulation.
Using the On-line Ad Platforms in the Small Business Commercial Activities
Authors:   Central Ukrainian National Technical University, Zahreba M. M. , Nikolaiev I. V. ,   Central Ukrainian National Technical University
Published: December 2020

The article is aimed at studying the market of on-line ad platforms in Ukraine, as well as the opportunities that it provides to small businesses in the sphere of product promotion and sales. When analyzing and generalizing the scientific works of scholars, it was found that they do not consider the on-line ad platforms as an instrument that can give a new impetus in the commercial activities of small businesses and private entrepreneurs. Given the protracted economic crisis due to the COVID-19 pandemic, the use and research of these platforms appears to be all the more topical issue. The common characteristics of the on-line ad sites as categories are allocated, the related marketplaces are examined. The presented in Ukraine electronic bulletin boards, their features, differences, strengths and weaknesses are researched. Mechanisms for using these platforms in commercial activities of enterprises are proposed. A comparison of on-line ads with the creation of an own website and on-line store is made; advantages and disadvantages of both options are provided. Separately, the creation of an on-line store at the proposed marketplace as a compromise option is allocated. The benefits of paid ads are considered. The possibilities that can be provided through ads for an additional fee are explored. The possible hazards and types of fraud in trading through electronic bulletin boards, as well as ways to avoid them, are specified. Prospects for further research in this direction are to improve the awareness of users about fraud opportunities, as well as development of new mechanisms for identifying users and making payments capable of complicating or, in the ideal case, preventing criminal actions.
A Classification of Risks of Foreign Economic Activity for the Accountance Needs
Authors:   The National Academy of Statistics, Accounting and Auditing, Kinzerska N. V.
Published: December 2020

Implementation of foreign economic activity in a volatile economic environment, influence of uncertainty on the results and the effectiveness of foreign economic operations cause the need for accounting reflection of the consequences of risks of foreign economic activity. On the basis of studying the approaches of different authors and scholars to the interpretation of the essence of the concept of «risk of foreign economic activity», the economic content of this concept is determined and an author’s own definition is proposed. According to the results of the study of existing classification features and types of risks of foreign economic activity, the need to expand and improve them is substantiated. A classification of risks of foreign economic activity for accounting needs, taking into account the peculiarities of the formation of an institutional environment and the specifics of implementation of foreign economic operations, is scientifically substantiated and presented. It is proved that the use of the proposed classification of risks of foreign economic activity will ensure the formation of a comprehensive system of accumulation of information on the probability of occurrence and source of formation of risks of foreign economic activity of trade enterprises, their impact on accounting objects, indicators of financial statements and results of the operation of the enterprise. If the consequences of the risks of foreign economic activity, along with the measures aimed at minimization of them, can be reflected promptly and correctly, it is possible to ensure that the optimal financial results of trading enterprises in conditions of uncertainty can be achieved.
The Approaches to the Formation and Assessment of the Financial Stability of Enterprise
Authors:   Dmytro Motornyi Tavria State Agrotechnological University, Zakharova N. Y.
Published: December 2020

The article is aimed at allocating approaches to determining the essence of financial stability, factors that cause it and substantiating the basic methodical approaches to its assessment. The approaches to determining the essence of financial stability are systematized, namely: as the status of both enterprise and its financial resources; as both ability and capacity of the enterprise to fulfill certain obligations and achieve results; both as an integrated and generalizing characteristic of the enterprise in general or as its financial position in particular; as solvency ensured in a certain time period and under certain conditions. The author substantiates the importance of assessing financial stability, the purpose of which is to determine the degree of dependence of the enterprise on external sources of financing, the level of financial risk, the ability to fulfill financing at the expense of the own financial resources, setting the zone and reserve of financial stability. The main features of financial stability of the enterprise and approaches to its assessment are singled out. The need to analyze the structure of financial resources is substantiated and the algorithm of grouping of the own, involved and borrowed financial resources in accordance with certain articles of balance is provided. A calculation mechanism is presented and the values of the main indicators used to assess financial stability are outlined. It is emphasized that only a balanced approach to the formation of a certain level of financial stability on the basis of its careful valuation can be the guarantee to a stable growth of business profitability, ensuring creditworthiness and investment attractiveness of the enterprise.
Development of Microfinance Organizations in Ukraine in Terms of FinTech Financial Market Transformation
Authors:   National Technical University «Dnipro Polytechnic», Krylova O. V.
Published: December 2020

Modern operation conditions of the market of non-bank financial services in Ukraine require the search for unconventional forms of innovation development and the need to implement information systems and digital technologies. This corresponds to the provisions of the Association Agreement between Ukraine and the EU, the Comprehensive Program for the Development of the Financial Sector of Ukraine until 2020, the Financial Sector Development Strategies and FinTech in Ukraine by 2025. The research is aimed at identifying the major tendencies in the development of microfinance organizations in Ukraine as a key element of the market of non-bank financial services using digital technologies, including FinTech. To achieve the aim, research methods such as analysis and synthesis, statistical analysis, comparison, generalization, structural and logical method, expert survey and estimation are used. The dynamics of the main indicators of the development of the market of non-bank financial services in Ukraine are analyzed: the number of microfinance organizations, the volume of assets and financial services. The specific features of «split» as an important reform of the development of the national market of non-bank financial services have been identified. The peculiarities of FinTech development in different world countries are researched. The content of the key development tendencies of microfinance organizations in terms of FinTech-transformation of the financial sector in Ukraine are covered, including: marketplaces (providing loans to customers through intermediary digital platforms); balance crediting; AI-based solutions; banking-as-a-service as a model that allows non-financial companies to add banking services to their own applications and digital products. The formation and implementation of a qualitatively new model of regulation of the market of non-bank financial services will create conditions for the use of new financial instruments and business models that will meet the requirements of the dynamic institutional environment of microfinance organizations in Ukraine.
Analyzing the Innovative Activity of the Industrial Enterprises of Ukraine in Kharkiv Region
Authors:   Kharkiv National University of Construction Engineering and Architecture, Koliedina K. O.
Published: December 2020

It is defined that the important role in the development of Ukrainian economy belongs to the industrial production sector, wherein the scientific-technological progress and innovation are generated, presenting this very sector as a «driver» of economic growth. It is determined that the largest number of innovatively active industrial enterprises of Ukraine is located in Kharkiv region. Hence, the article is aimed at researching the status of innovative activity of industrial enterprises of Kharkiv region. The analysis of the main indicators of innovation activity of industrial enterprises of the region was carried out. It was identified that the share of enterprises that introduced innovations is insignificant, and the share of innovative products sold by them is generally little tangible in the total volume of the products sold. It is reasoned that this situation may indicate a negative tendency of deterioration of the quality of innovative products and its uncompetitiveness in the market. The distribution of the total costs of industrial enterprises of Kharkiv region by the directions of their innovation activity is researched. It is defined that the bulk of innovation costs are directed by enterprises to purchase machinery and equipment, and the share of costs for the internal and external R&D is extremely small, which indicates the imperfection and irrationality of the existing structure of costs. It is determined that the key factor in stimulating innovation activity at industrial enterprises of Kharkiv region is the attraction of the governmental and foreign investments for the development, creation and implementation of innovations, since the main source of innovation financing at present is the own funds of enterprises. It is proved that without changing the present day situation with regulation in the field of innovations, an increase in the competitiveness of industrial enterprises of Kharkiv region in the near future and an acceleration of the pace of their innovative development is problematic.
UM REFERENCIAL TEÓRICO ACERCA DO ÍON SÓDIO E SEU SAL DE PRINCIPAL OCORRÊNCIA COTIDIANA – O CLORETO DE SÓDIO – POTENCIALMENTE CONTRIBUTIVO AO ENSINO DE QUÍMICA
Authors: Silva da Silva André Luís , De Guarçoni Martins Daniel , Garcez de Moura Paulo Rogério , Santos de Medeiros Garcia Ana Raquel
Published: December 2020

Neste artigo é apresentada uma breve fundamentação teórica decorrente da pesquisa bibliográfica sobre o elemento químico sódio, seu cátion monovalente e sal de principal ocorrência cotidiana, o cloreto de sódio. Nessa perspectiva, valendo-se de legislações nacionais e da literatura específica, são discutidos os subtemas (i) teores de sódio e de íon sódio: o caso do biscoito tipo disquinho de cebola; (ii) consumo de sódio: dos padrões, recomendações e hábitos às conceituações; (iii) De conservante alimentar a corriqueiro tempero; (iv) Atuação do íon sódio na fisiologia humana e (v) Ocorrência natural do cloreto de sódio e seus processos de obtenção/produção. Com enfoque na saúde e nutrição humana, objetiva-se, com isso, contribuir ao entendimento qualificado sobre a temática, subsidiando atuações didáticas e sociais.
تأثير المضامين السلوكية للمعلومات في اختيار الطرائق المحاسبية وانعكاسها على قرارات المستثمرين دراسة ميدانية في سوق العراق للأوراق المالية
Authors: Hussein AL-Aameri Omar Ali , H. Yahiya Al-Temimi Abbas
Published: December 2020

يهدف البحث الى القاء الضوء على المدخل السلوكي في المحاسبة ، وبيان المضامين السلوكية للأنشطة الرئيسة للمحاسبة ، وتوضيح مفهوم حث المعلومات في أطار المدخل السلوكي وتأثيره في اعداد القوائم المالية . وبيأن تأثير المعلومات المالية على سلوك متخذي القرارات الاستثمارية ، ولتحقيق اهداف البحث قام الباحث بإعداد أستمارة للأستبانة وعلى وفق مقياس ليكرت الخماسي ، وقد أخذ بنظر الاعتبار في إعدادها التوافق مع خصائص مجتمع الدراسة ، وأن المجتمع المستهدف لهذه الأستبانة هو المستثمرون في سوق العراق للأوراق المالية.

وقد توصل الباحث الى مجموعة من الأستنتاجات والتوصيات ومن أبرز الأستنتاجات ما يأتي: ان هناك تأثير معنوي ذات دلالة احصائية للمضامين السلوكية للمعلومات في اختيار الطرائق المحاسبية ،وهناك تأثير معنوي ذات دلالة احصائية للطرائق المحاسبية على قرارات المستثمرين بوجود المضامين السلوكية للمعلومات وان توقع المحاسب لنتائج استخدام المعلومات ، قد يؤدي به وقبل توصيل أي معلومات، وبالتالي حتى قبل ظهور أي نتائج ان يختار تغير المعلومات أو سلوكه أو حتى اهدافه ،ويمكن التنبؤ بسلوك الأفراد وتوجيه هذا السلوك بالصورة المناسبة من خلال توفير المعلومات المناسبة في عملية أتخاذ القرارات ،ومن خلال ادراك المحاسب لردود فعل المستخدمين على الطرائق المحاسبية ، يمكن له من استخدام الطرائق المحاسبية البديلة المفضلة لهم، إما أهم التوصيات ما يأتي :ضرورة مراعاة معدوا المعلومات المحاسبية للجوانب السلوكية ، واخذ رد فعل المستخدمين للمعلومات المحاسبية بنظر الأعتبار عند ممارسة العمل المحاسبي ، واختيار الطرائق المحاسبية ،وضرورة الاهتمام بالمعلومات التي تقدم إلى المستثمرين ، والتي تساعدهم على اتخاذ القرارات الاستثمارية ، وتقديم هذه المعلومات بشكل دوري ومنظم وتوفيرها بالسرعة والدقة الممكنة ، والعمل على توفير المعلومات الملاءمة بالكم والنوع والوقت المناسب من أجل تسهيل اتخاذ القرار الاستثماري السليم .
Impact of luteinizing hormone suppression on hematopoietic recovery after intensive chemotherapy in patients with leukemia
Authors: Dalle Iman Abou , Paranal Ronald , Zarka Jabra , Paul Shilpa , Sasaki Koji , Li Wen , Ning Jing , Short Nicholas J. , Ohanian Maro , Cortes Jorge E. , Jabbour Elias J. , Issa Ghayas C.
Published: December 2020

Treatment of acute leukemia with intensive chemotherapy leads to an increased risk of myelosuppression. Luteinizing hormone (LH) blockade improves hematopoietic recovery in mice after radiation or chemotherapy, through protection of the hematopoietic stem cells which express the LH receptor. We hypothesized that LH blockade improves hematopoietic recovery following intensive chemotherapy in patients with leukemia. We conducted a retrospective analysis on pre-menopausal women with acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL) who received intensive chemotherapy and leuprolide given for abnormal uterine bleeding prevention or treatment. Given that leuprolide was more commonly administered in younger patients, we performed propensity score matching between the leuprolide (AML N=64; ALL N=49) and control groups (AML N=128; ALL N=98 patients). Patients with AML who received leuprolide had an additional increase of 13.8 x 109/L/year in their platelet count, and a 0.19 x 109/L/year increase in their lymphocyte count after chemotherapy compared to control (P=0.02; P=0.03 respectively). Those with ALL who received leuprolide had an additional increase of 0.37 x 109/L/year in their absolute neutrophil count (P=0.02). In AML, leuprolide was associated with higher long-term hemoglobin levels (P
Desensitization is an essencial part of your patient protocol at the dental appointment
Authors:   National Medical University named after A.A. Bogomolets, Kiev, Ukraine, Symonenko R. , Vasylieva-Katashynskaya N. ,   Kyiv Dentistry
Published: December 2020

The process of eliminating hyperesthesia of hard dental tissues is a standard method of pathogenetic treatment in conservative dentistry. Patients of almost all age groups are faced with increased tooth sensitivity (hypersensitivity) and in most cases it is one of the symptoms of other pathologies.This is the reason for the constantly growing interest of scientists and clinicians in the problems of desensitization of teeth, which is undoubtedly is the first step in the rehabilitation process for patients with various dental pathologies. Features, hyperesthesia of hard dental tissues requires etiotropic treatment. However, we have the opportunity to influence the pathogenetic link and eliminate the significant symptoms of the disease by reducing dentinal permeability (minimizing the hydrodynamic processes that cause a painful reaction) directly at the dental appointment. Desensitizers and fluoride-containing agents are very effective in solving this problem. There is no doubt that the dentist needs to be well versed in the active ingredients of desensitizing agents, their mechanisms of action, significant advantages and indications for use. There is no universal remedy. Some patients need more than one type of treatment at the same time. Our extremely positive and long-term experience of using the medications of the VOCO company (Germany) will help to make unquestionable and right choice of drugs to eliminate dental hyperesthesia.
Essays on the historical formation of orthodontics as a university discipline in Lviv in the 19th-20th centuries
Authors:   Danylo Halytskyi Lviv National Medical University, Ukraine, Makeev V. , Grinovets V. ,   Danylo Halytskyi Lviv National Medical University, Ukraine, Petrishin О. ,   Danylo Halytskyi Lviv National Medical University, Ukraine
Published: December 2020

Summary. The development of the University School of Orthodontics within the framework of the science of odontology began in Lviv in the early 19th century. The science of orthodontics was taught as a subject at the Faculty of Medicine of Lviv University. Medical students studied the basics of the formation of mixed dentition in children and the influence on the formation of permanent occlusion with the possibilities of prosthetics of that time. Formation of orthodontics as a modern branch in dentistry began in the middle of the twentieth century, to which the scientists mentioned in this article joined. From that time until today, the departments of dentistry at the Danylo Halytsky National Medical University provide training for students, and at the present level scientific work is being conducted which creates an opportunity to improve this specialty.
El uso de las redes sociales: algunos ejemplos tomados de museos de Castilla y León
Authors: Bellido Blanco Antonio
Published: December 2020

Se analizan cuatro ejemplos de gestión de las redes sociales que se salen de la gestión rutinaria de las redes sociales tomados de instituciones museísticas de Castilla y León. A partir de su análisis se reflexiona sobre los problemas que pueden surgir en la gestión de este recurso de comunicación.
Influence of water pressure and abrasive materials nature on the duration of the high-pressure abrasive water jet cutting in building structures
Authors: Василевич Дмитрий Владимирович , Лахвич Вячеслав Вячеславович , Родак Вячеслав Яковлевич
Published: December 2020

Purpose. Improving the efficiency of abrasive water jet cutting by choosing rational process parameters and abrasive material.

Methods. Full-scale tests within the program of a full-factor experiment on cutting a high-pressure barrel into building structures, statistical data processing.

Findings. Experimental data on the time of the high-pressure cutting barrel into building structures made of various materials have been obtained.

Application field of research. The research results can be used by fire rescue units in emergency response.
MICROENCAPSULATION of grapefruit oil with sodium alginate by gelation and ionic extrusion: optimization and modeling of crosslinking and study of controlled release kinetics.
Authors: Cáceres Liliana Mariel , Velasco Gustavo Adolfo , Dagnino Eliana Paola , Chamorro Ester R
Published: December 2020

Essential grapefruit oil with high concentrations of limonene is used in food, cosmetic and pharmaceutical industries due to its antimicrobial properties, fragrance, and flavor. To facilitate its manipulation and protect it from adverse environmental factors, the microencapsulation is used. The objective of this work was to optimize the microencapsulation process of grapefruit oil using external ionic gelation coupled to extrusion with sodium alginate and calcium chloride. We achieved the best encapsulation conditions with calcium chloride concentration at 7.4% w/v and a crosslinking time of 58 minutes, obtaining a yield of 62% and an efficiency of 100% with an oil loading capacity of 10% w/w. The chemical adsorption of calcium as well during the crosslinking process was studied, observing a significant fit with the Elovich equation. And an adjustment of the controlled release of the oil was obtained to the empirical kinetic model of Korsmeyer and Peppas.
Analisis Daya Dukung Dan Penurunan Pondasi Tiang Pancang Proyek Gedung DPRD Kabupaten Pemalang
Authors: Azizi Amris , Salim M. Agus , Ramadhon Gilang
Published: December 2020

Pondasi merupakan bagian penting dari suatu bangunan yang berfungsi memikul beban bangunan dan beban lainnya dan meneruskannya ke dalam tanah sampai ke lapisan atau kedalaman tertentu. Dalam perencanaan pondasi terlebih dahulu harus dihitung dan ditentukan kapasitas dukung rencana. Hal lain yang penting diperhitungkan adalah besarnya penurunan pondasi. Tujuan dari penelitian ini adalah menganalisis daya dukung dan penurunan pondasi tiang pancang pada proyek gedung DPRD Kabupaten Pemalang. Penelitian dilakukan dengan menganalisis data berupa hasil uji test SPT dan shop drawing. Berdasarkan hasil analisis didapat seluruh pondasi tiang pancang mampu menahan beban yang bekerja diatasnya, sehingga pondasi dikategorikan aman (Qall > Pp). Dengan perbandingan dari beban terbesar pada pondasi tipe 1 sebesar 145,727 ton > 49,962 ton, pondasi tipe 2 sebesar 290,710 ton > 107,077 ton, pondasi tipe 3 sebesar 579,930 ton >380,931 ton dan pondasi tipe 4 sebesar 727,396 ton > 489,773 ton. Penurunan yang terjadi pada pondasi sedalam 0,029 m atau lebih kecil dari penurunan ijinnya yaitu sebesar 10% diameter.
Differences in nurses’ perceptions of self-reported pain and the administered morphine dose according to the patient’s facial expression in Korea
Authors: Park Jeong Yun , Lee Da In
Published: December 2020

Purpose: This study aimed to compare nurses’ perceptions of self-reported pain, the recorded pain score, and pain treatment according to the patient’s facial expression.Methods: In this descriptive cross-sectional survey, the participants were 472 nurses working at a tertiary hospital in Seoul, Korea. A self-report questionnaire presented nurses with a smiling patient complaining of acute post-surgical pain and a grimacing patient with cancer pain, both of whom reported a pain level of 8 out of 10, and asked nurses to indicate their perception of the pain intensity, the pain score that they would record, and the medication that they would provide for each patient.Results: The pain intensity perceived by nurses for the grimacing patient was significantly higher than that for the smiling patient (P<0.001). The recorded pain score was likewise significantly higher for the grimacing patient than for the smiling patient (P<0.001). There was a significant difference in the amount of morphine chosen by the nurses for pain interventions between the smiling and grimacing patients (P=0.040). Higher perceived pain intensity and score were associated with higher administered doses of morphine.Conclusion: These findings suggest that nurses might be affected by patients’ facial expressions when treating pain. A pain management program should be developed that trains nurses to accurately recognize pain hidden in patients’ faces and provides them with the knowledge of how to appropriately assess and manage patients’ pain.
Climate change and maize production in the Vaal catchment of South Africa: assessment of farmers’ awareness, perceptions and adaptation strategies
Authors: Akanbi RT , Davis N , Ndarana T
Published: December 2020

In recent years, maize production in South Africa has faced challenges related to climate change which have prompted farmers to adapt their production activities. We assessed factors informing the adaptive decision-making of maize farmers in the Vaal catchment by examining linkages between farmers’ experiences, their perceptions of climate change and the adaptation strategies they use. Data were collected through semi-structured household-level interviews, key informant interviews and focus group discussions. Catchment climate data were also collected to determine key 30 yr trends (1989-2018) and the farmers’ level of awareness about these trends. Data were analysed using descriptive statistics, Mann-Kendall (MK) test, Sen’s slope test, climate anomalies and multinomial logit modelling. Results suggest that maize farmers in the catchment are aware of climate change (95%), with many of them referring to it as ‘a shift in climate’. This perceived ‘shift’ is supported by meteorological data, as the MK test confirmed a decreasing inter-annual precipitation trend (-0.149) and a decreasing trend at the onset of the maize planting season (-0.167), with temperature showing an increasing trend (0.470). These trends have inspired the adoption of a range of timing-related responses and other farming and off-farm adaptations. Modelling results revealed farmer perception, farmer typology and the nature of maize production (rainfed) as some of the variables with a deciding influence on the nature of the adaptation employed. The study confirms the importance of understanding intersections between qualitative and quantitative variables in triggering adaptive responses. Current strategies need to be expanded and supplemented to improve resilience and prevent maladaptation.
Experimental Evaluation of Using Silica Aerogels as the Thermal Insulator for Combustor Liners
Authors: Pyo Yeongmin , Robertson Taylor , Yun Sean , Hong Zekai
Published: December 2020

An experimental study was conducted for evaluating the feasibility of using silica aerogel as thermal insulator for combustor liners. Aerogels are a superior material for minimizing heat flux to the metal structure of the combustion liner due to their low thermal conductivity. In this study, a conical natural gas fired swirling-flame combustor was utilized for reproducing the combustion environment. The silica aerogel blanket was attached to the inner side of a perforated combustor liner. Temperature distribution on the outer side of the combustion liner was measured using a calibrated IR camera. To create a protective cooling film over the aerogel surface, cooling air was supplied from the back side of the perforated metal liner and was allowed to penetrate the silica aerogel blanket to be discharged to the combustor. As the combustor was operated at a fixed equivalence ratio of 0.83, cooling air flow rates were varied to evaluate the effectiveness of transpiration cooling on the aerogel blanket as various cooling flow rates.

The measured evolution of temperature distribution confirmed thermal equilibriums for every test condition with transpiration cooling. The measured temperature distribution of metal liner demonstrated superior thermal insulation of aerogel blanket under the protection of cooling film with a temperature difference as high as 1580 K between combustion products temperature and the metal liner temperature on the back side. In addition, silica aerogel samples were examined before and after the combustion tests to understand their material degradation exposing to a typical gas turbine combustor environment using high-resolution scanning electron microscope (SEM). Test results suggest multiple degradation mechanisms to the silica aerogel blanket samples from the combustion tests. Improvements can be made to the silica aerogel blankets for a more resilient thermal insulator, for example, by replacing glass fibers in silica aerogels.
Impact of Oxygen Supply and Scale Up on Mycobacterium smegmatis Cultivation and Mycofactocin Formation
Authors: Peña-Ortiz Luis , Schlembach Ivan , Lackner Gerald , Regestein Lars
Published: December 2020

Mycofactocin (MFT) is a recently discovered glycosylated redox cofactor, which has been associated with the detoxification of antibiotics in pathogenic mycobacteria, and, therefore, of potential medical interest. The MFT biosynthetic gene cluster is commonly found in mycobacteria, including Mycobacterium tuberculosis, the causative agent of tuberculosis. Since the MFT molecule is highly interesting for basic research and could even serve as a potential drug target, large-scale production of the molecule is highly desired. However, conventional shake flask cultivations failed to produce enough MFT for further biochemical characterization like kinetic studies and structure elucidation, and a more comprehensive study of cultivation parameters is urgently needed. Being a redox cofactor, it can be hypothesized that the oxygen transfer rate (OTR) is a critical parameter for MFT formation. Using the non-pathogenic strain Mycobacterium smegmatis mc2 155, shake flask experiments with online measurement of the oxygen uptake and the carbon dioxide formation, were conducted under different levels of oxygen supply. Using liquid chromatography and high-resolution mass spectrometry, a 4–8 times increase of MFT production was identified under oxygen-limited conditions, in both complex and mineral medium. Moreover, the level of oxygen supply modulates not only the overall MFT formation but also the length of the glycosidic chain. Finally, all results were scaled up into a 7 L stirred tank reactor to elucidate the kinetics of MFT formation. Ultimately, this study enables the production of high amounts of these redox cofactors, to perform further investigations into the role and importance of MFTs.
New Putative Antimicrobial Candidates: In silico Design of Fish-Derived Antibacterial Peptide-Motifs
Authors: Okella Hedmon , Georrge John J. , Ochwo Sylvester , Ndekezi Christian , Koffi Kevin Tindo , Aber Jacqueline , Ajayi Clement Olusoji , Fofana Fatoumata Gnine , Ikiriza Hilda , Mtewa Andrew G. , Nkamwesiga Joseph , Bassogog Christian Bernard Bakwo , Kato Charles Drago , Ogwang Patrick Engeu
Published: December 2020

Antimicrobial resistance remains a great threat to global health. In response to the World Health Organizations’ global call for action, nature has been explored for novel and safe antimicrobial candidates. To date, fish have gained recognition as potential source of safe, broad spectrum and effective antimicrobial therapeutics. The use of computational methods to design antimicrobial candidates of industrial application has however, been lagging behind. To fill the gap and contribute to the current fish-derived antimicrobial peptide repertoire, this study used Support Vector Machines algorithm to fish out fish-antimicrobial peptide-motif candidates encrypted in 127 peptides submitted at the Antimicrobial Peptide Database (APD3), steered by their physico-chemical characteristics (i.e., positive net charge, hydrophobicity, stability, molecular weight and sequence length). The best two novel antimicrobial peptide-motifs (A15_B, A15_E) with the lowest instability index (−28.25, −22.49, respectively) and highest isoelectric point (pI) index (10.48 for each) were selected for further analysis. Their 3D structures were predicted using I-TASSER and PEP-FOLD servers while ProSA, PROCHECK, and ANOLEA were used to validate them. The models predicted by I-TASSER were found to be better than those predicted by PEP-FOLD upon validation. Two I-TASSER models with the lowest c-score of −0.10 and −0.30 for A15_B and A15_E peptide-motifs, respectively, were selected for docking against known bacterial-antimicrobial target-proteins retrieved from protein databank (PDB). Carbapenam-3-carboxylate synthase (PDB ID; 4oj8) yielded the lowest docking energy (−8.80 and −7.80 Kcal/mol) against motif A15_B and A15_E, respectively, using AutoDock VINA. Further, in addition to Carbapenam-3-carboxylate synthase, these peptides (A15_B and A15_E) were found to as well bind to membrane protein (PDB ID: 1by3) and Carbapenem synthetase (PDB: 1q15) when ClusPro and HPEPDOCK tools were used. The membrane protein yielded docking energy scores (DES): −290.094, −270.751; coefficient weight (CW): −763.6, 763.3 for A15_B and A15_E) whereas, Carbapenem synthetase (PDB: 1q15) had a DES of −236.802, −262.75 and a CW of −819.7, −829.7 for peptides A15_B and A15_E, respectively. Motif A15_B of amino acid positions 2–19 in Pleurocidin exhibited the strongest in silico antimicrobial potentials. This segment could be a good biological candidate of great application in pharmaceutical industries as an antimicrobial drug candidate.
Multi-Path Optimization for Efficient Production of 2′-Fucosyllactose in an Engineered Escherichia coli C41 (DE3) Derivative
Authors: Ni Zhijian , Li Zhongkui , Wu Jinyong , Ge Yuanfei , Liao Yingxue , Yuan Lixia , Chen Xiangsong , Yao Jianming
Published: December 2020

2′-fucosyllactose (2′-FL), one of the simplest but most abundant oligosaccharides in human milk, has been demonstrated to have many positive benefits for the healthy development of newborns. However, the high-cost production and limited availability restrict its widespread use in infant nutrition and further research on its potential functions. In this study, on the basis of previous achievements, we developed a powerful cell factory by using a lacZ-mutant Escherichia coli C41 (DE3)ΔZ to ulteriorly increase 2′-FL production by feeding inexpensive glycerol. Initially, we co-expressed the genes for GDP-L-fucose biosynthesis and heterologous α-1,2-fucosyltransferase in C41(DE3)ΔZ through different plasmid-based expression combinations, functionally constructing a preferred route for 2′-FL biosynthesis. To further boost the carbon flux from GDP-L-fucose toward 2′-FL synthesis, deletion of chromosomal genes (wcaJ, nudD, and nudK) involved in the degradation of the precursors GDP-L-fucose and GDP-mannose were performed. Notably, the co-introduction of two heterologous positive regulators, RcsA and RcsB, was confirmed to be more conducive to GDP-L-fucose formation and thus 2′-FL production. Further a genomic integration of an individual copy of α-1,2-fucosyltransferase gene, as well as the preliminary optimization of fermentation conditions enabled the resulting engineered strain to achieve a high titer and yield. By collectively taking into account the intracellular lactose utilization, GDP-L-fucose availability, and fucosylation activity for 2′-FL production, ultimately a highest titer of 2′-FL in our optimized conditions reached 6.86 g/L with a yield of 0.92 mol/mol from lactose in the batch fermentation. Moreover, the feasibility of mass production was demonstrated in a 50-L fed-batch fermentation system in which a maximum titer of 66.80 g/L 2′-FL was achieved with a yield of 0.89 mol 2′-FL/mol lactose and a productivity of approximately 0.95 g/L/h 2′-FL. As a proof of concept, our preliminary 2′-FL production demonstrated a superior production performance, which will provide a promising candidate process for further industrial production.
Projected Climate Change Impacts on Hurricane Storm Surge Inundation in the Coastal United States
Authors: Camelo Jeane , Mayo Talea L. , Gutmann Ethan D.
Published: December 2020

The properties of hurricanes directly influence storm surges; however, the implications of projected changes to the climate are unclear. Here, we simulate the storm surges of historical storms under present day and end of century climate scenarios to assess the impact of climate change on storm surge inundation. We simulate 21 storms that impacted the Gulf of Mexico and Atlantic Coasts of the continental U.S. from 2000 to 2013. We find that the volume of inundation increases for 14 storms and the average change for all storms is +36%. The extent of inundation increases for 13 storms, and the average change for all storms is +25%. Notable increases in inundation occur near Texas, Louisiana, Mississippi, the west coast of Florida, the Carolinas, and New Jersey. Our calculations of inundation volume and extent suggest that at the end of the century, we can expect hurricanes to produce larger storm surge magnitudes in concentrated areas, as opposed to surges with lower magnitudes that are widespread. We examine changes in maximum wind speed, minimum central pressure, translation speed, and radius of the 33 ms−1wind to assess the impacts of individual storm characteristics on storm surge. We find that there is no single storm characteristic that directly relates to storm surge inundation or its climate induced changes. Even when all the characteristics are considered together, the resulting influences are difficult to anticipate. This is likely due to the complexity of the hydrodynamics and interactions with local geography. This illustrates that even as climate change research advances and more is known about projected impacts to hurricanes, implications for storm surge will be difficult to predict without explicit numerical simulation.
Bisamide Derivative of Dicarboxylic Acid Contributes to Restoration of Testicular Tissue Function and Influences Spermatogonial Stem Cells in Metabolic Disorders
Authors: Pakhomova Angelina , Pershina Olga , Nebolsin Vladimir , Ermakova Natalia , Krupin Vyacheslav , Sandrikina Lubov , Pan Edgar , Widera Darius , Dygai Alexander , Skurikhin Evgenii
Published: December 2020

Metabolic syndrome can lead to several challenging complications including degeneration of the pancreas and hypogonadism. Recently, we have shown that Bisamide Derivative of Dicarboxylic Acid (BDDA) can contribute to pancreatic restoration in mice with metabolic disorders via its positive effects on lipid and glucose metabolism, and by increasing the numbers of pancreatic stem cells. In the present study, we hypothesized that BDDA might also be effective in restoring hypogonadism caused by metabolic syndrome. Experiments were performed on male C57BL/6 mice with hypogonadism, where metabolic disorders have been introduced by a combination of streptozotocin treatment and high fat diet. Using a combination of histological and biochemical methods along with a flow cytometric analysis of stem and progenitor cell markers, we evaluated the biological effects of BDDA on testicular tissue, germ cells, spermatogonial stem cells in vitro and in vivo, as well as on fertility. We demonstrate that in mice with metabolic disorders, BDDA has positive effects on spermatogenesis and restores fertility. We also show that BDDA exerts its therapeutic effects by reducing inflammation and by modulating spermatogonial stem cells. Thus, our results suggest that BDDA could represent a promising lead compound for the development of novel therapeutics able to stimulate regeneration of the testicular tissue and to restore fertility in hypogonadism resulting from complications of metabolic syndrome.
Altered Insulin Receptor Substrate 1 Phosphorylation in Blood Neuron-Derived Extracellular Vesicles From Patients With Parkinson’s Disease
Authors: Chou Szu-Yi , Chan Lung , Chung Chen-Chih , Chiu Jing-Yuan , Hsieh Yi-Chen , Hong Chien-Tai
Published: December 2020

Introduction

Diabetes increases the risk of Parkinson’s disease (PD). The phosphorylation of type 1 insulin receptor substrate (IRS-1) determines the function of insulin signaling pathway. Extracellular vesicles (EVs) are emerging as biomarkers of human diseases. The present study investigated whether PD patients exert altered phosphorylation IRS-1 (p-IRS-1) inside the blood neuron-derived extracellular vesicles (NDEVs).

Research Design and Methods

In total, there were 94 patients with PD and 63 healthy controls recruited and their clinical manifestations were evaluated. Blood NDEVs were isolated using the immunoprecipitation method, and Western blot analysis was conducted to assess total IRS-1, p-IRS-1, and downstream substrates level in blood NDEVs. Statistical analysis was performed using SPSS 19.0, and p < 0.05 was considered significant.

Results

The isolated blood EVs were validated according to the presence of CD63 and HSP70, nanoparticle tracking analysis and transmission electron microscopy. NDEVs were positive with neuronal markers. PD patients exerted significantly higher level of p-IRS-1S312 in blood NDEVs than controls. In addition, the p-IRS-1S312 levels in blood NDEVs was positively associated with the severity of tremor in PD patients after adjusting of age, sex, hemoglobin A1c, and body mass index (BMI).

Conclusion

PD patients exerted altered p-IRS-1S312 in the blood NDEVs, and also correlated with the severity of tremor. These findings suggested the association between dysfunctional insulin signaling pathway with PD. The role of altered p-IRS-1S312 in blood NDEVs as a segregating biomarker of PD required further cohort study to assess the association with the progression of PD.
Sex-Determining Region Y Chromosome-Related High-Mobility-Group Box 10 in Cancer: A Potential Therapeutic Target
Authors: Yu Liming , Peng Fan , Dong Xue , Chen Ying , Sun Dongdong , Jiang Shuai , Deng Chao
Published: December 2020

Sex-determining region Y-related high mobility group-box 10 (SOX10), a member of theSOXfamily, has recently been highlighted as an essential transcriptional factor involved in developmental biology. Recently, the functionality of SOX 10 has been increasingly revealed by researchers worldwide. It has been reported that SOX10 significantly regulates the proliferation, migration, and apoptosis of tumors and is closely associated with the progression of cancer. In this review, we first introduce the basic background of the SOX family and SOX10 and then discuss the pathophysiological roles of SOX10 in cancer. Besides, we enumerate the application of SOX10 in the pathological diagnosis and therapeutic potential of cancer. Eventually, we summarize the potential directions and perspectives of SOX10 in neoplastic theranostics. The information compiled herein may assist in additional studies and increase the potential of SOX10 as a therapeutic target for cancer.
Down Regulation of SIRT2 Reduced ASS Induced NSCLC Apoptosis Through the Release of Autophagy Components via Exosomes
Authors: Wang Lei , Xu Pei , Xie Xiao , Hu Fengqing , Jiang Lianyong , Hu Rui , Ding Fangbao , Xiao Haibo , Zhang Huijun
Published: December 2020

Metastasis of cancer is the main cause of death in many types of cancer. Acute shear stress (ASS) is an important part of tumor micro-environment, it plays a crucial role in tumor invasion and spread. However, less is known about the role of ASS in tumorigenesis and metastasis of NSCLC. In this study, NSCLC cells were exposed to ASS (10 dyn/cm2) to explore the effect of ASS in regulation of autophagy and exosome mediated cell survival. Finally, the influence of SIRT2 on NSCLC cell metastasis was verified in vivo. Our data demonstrates that ASS promotes exosome and autophagy components releasing in a time dependent manner, inhibition of exosome release exacerbates ASS induced NSCLC cell apoptosis. Furthermore, we identified that this function was regulated by sirtuin 2 (SIRT2). And, RNA immunoprecipitation (RIP) assay suggested SIRT2 directly bound to the 3′UTR of transcription factor EB (TFEB) and facilitated its mRNA stability. TFEB is a key transcription factor involved in the regulation of many lysosome related genes and plays a critical role in the fusion of autophagosome and lysosome. Altogether, this data revealed that SIRT2 is a mechanical sensitive protein, and it regulates ASS induced cell apoptosis by modulating the release of exosomes and autophagy components, which provides a promising strategy for the treatment of NSCLCs.
Influence of Solvents' Polarity on the Physicochemical Properties and Photocatalytic Activity of Titania Synthesized Using Deinbollia pinnata Leaves
Authors: Rufai Yakubu , Chandren Sheela , Basar Norazah
Published: December 2020

Nanotechnology is one of the most interesting areas of research due to its flexibility to improve or form new products from nanoparticles (NPs), and as a fast, greener, more eco-friendly and sustainable solution to technological and environmental challenges. Among metal oxides of photocatalytic performance, the use of titania (TiO2) as photocatalyst is most popular due to its unique optical and electronic properties. Despite the wide utilization, the synthesis of TiO2 NPs bears many disadvantages: it utilizes various less environmental-friendly chemicals, high cost, requires high pressure and energy, and potentially hazardous physical and chemical methods. Hence, the development of green synthesis approach with eco-friendly natural products can be used to overcome these adverse effects. In this work, TiO2 NPs have been prepared by using Deinbollia pinnata leaves extracts, obtained by different solvents (n-hexane, ethyl acetate, and ethanol) with different polarities. The extracts acted as the reducing agent, while titanium isopropoxide as the precursor and water as the solvent. X-ray diffraction (XRD) pattern confirmed the synthesized TiO2 consist of anatase phase in high purity, with average crystallite size in the range of 19–21 nm. Characterization by using field emission scanning electron microscopy (FESEM) showed the TiO2 NPs possess a uniform semi-spherical shape in the size range of 33–48 nm. The energy dispersive X-ray (EDX) spectra of green TiO2 NPs showed two peaks for the main elements of Ti (61 Wt.%) and O (35 Wt.%). The band-gap energy of 3.2 eV was determined using UV-Vis spectroscopy. From the nitrogen sorption analysis, type V isotherm of the material was obtained, with BET surface area of 31.77 m2/g. The photocatalytic activity of synthesized TiO2 was evaluated for photodegradation of methyl orange (MO) under UV light irradiation. Based on the results, it is shown that TiO2 NPs synthesized with D. pinnata leaves extracted using ethyl acetate showed the most effective photodegradation performance, achieving 98.7% of MO conversion within 150 min. It can be concluded that the use of plant extracts in synthesis with TiO2 managed to produce highly crystalline anatase TiO2 with superior photocatalytic activity in the photodegradation of organic dye.