bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deficient Uracil Base Excision Repair Leads to Persistent dUMP in HIV Proviruses During Infection of Monocytes and Macrophages
Authors: Meshesha Mesfin , Esadze Alexandre , Cui Junru , Churgulia Natela , Sahu Sushil Kumar , Stivers James 
Published: January 2020

Abstract
Background Non-dividing cells of the myeloid lineage such as monocytes and macrophages are target cells of HIV that have low dNTP pool concentrations and elevated levels of dUTP, which leads to frequent incorporation of dUMP opposite to A during reverse transcription (“uracilation”). One factor determining the fate of dUMP in proviral DNA is the host cell uracil base excision repair (UBER) system. Here we explore the relative UBER capacity of monocytes (MC) and monocyte-derived macrophages (MDM) and the fate of integrated uracilated viruses in both cell types to understand the implications of viral dUMP on HIV diversification and infectivity.Results We find that monocytes are almost completely devoid of functional UBER, while macrophages are mainly deficient in the initial enzyme uracil DNA glycosylase (hUNG2). Accordingly, dUMP persists in viral DNA during the lifetime of a MC and can only be removed after differentiation of MC into MDM. Overexpression of human uracil DNA glycosylase in MDM prior to infection resulted in rapid removal of dUMP from HIV cDNA and near complete depletion of dUMP-containing viral copies. This finding establishes that the low hUNG2 expression level in these cells limits UBER but that hUNG2 is restrictive against uracilated viruses. In contrast, overexpression of hUNG2 after viral integration did not accelerate the excision of uracils, suggesting that they may poorly accessible in the context of chromatin. We found that viral DNA molecules with incorporated dUMP contained unique (+) strand transversion mutations that were not observed when dUMP was absent (G→T, T→A, T→G, A→C). These observations and other considerations suggest that dUMP introduces errors predominantly during (-) strand synthesis when the template is RNA. These mutations may arise from the increased mispairing and duplex destabilizing effects of dUMP relative to dTMP during reverse transcription. Overall, the likelihood of producing a functional virus from in vitro infection of MC is about 50-fold and 300-fold reduced as compared to MDM and activated T cells.Conclusions The results implicate viral dUMP incorporation in MC and MDM as a potential viral diversification and restriction pathway during human HIV infection.
Information Shocks and Corporate Cash Policies
Authors: Cheng C. S. Agnes , Huang Yuan , Li Xiao 
Published: January 2020

ABSTRACT
We examine how information environment affects corporate cash policy by examining the change in cash holdings around two events that lead to exogenous change in information environment, namely the initial enforcement of insider trading laws (ITLs) and the mandatory adoption of IFRS in European Union (EU) countries. Using a difference-in-differences approach, we find that firms decrease their cash holdings after both events. The decrease in cash holdings is more pronounced for firms with higher precautionary savings demand and with more severe agency problems. Additional tests show that the sensitivity of investment to cash holdings declines after the two events, consistent with the notion that the benefit of cash holdings in mitigating underinvestment and the private benefit of overinvesting cash holdings reduce after the events. Overall, our findings provide evidence that information environment improvements have real decision effects.
JEL Classifications: M41; M48; G31.
Adaptive Optical Systems in Air-Based Laser System. Analytical Review. Part 1. Current Status
Authors: Shanin Yu. I. 
Published: January 2020

Aviation-based laser complex is a complex technical object. Among its systems, we analyse only an adaptive optical system and issues related to its performance, and show that the effectiveness of the complex without an adaptive system is small. The analysis was carried out in terms of systems that were developed in the United States.Using the tilt corrector, an adaptive optics provides accurate tracking of the object. A deformable mirror performs correction of higher-order radiation wavefront aberrations caused by atmospheric turbulence for incoming light and outgoing laser radiation. The advantages of onboard laser systems are the beam propagation at the speed of light and the low price of a shot. The disadvantages are that the target should be in line-of-sight and there is a negative influence of the atmosphere. Another negative influences are vibrations of the aircraft and the aero-optical problem because of output radiation. An assured thermal target kill is possible at the range of 3-10 km. A functional kill and suppression are capable at ranges of 102-103times longer than for the thermal target kill.Among the programs for the development of an onboard laser in the USA, the YAL, ATL and ABL programs are considered. The YAL program is an attempt to intercept short-and medium-range missiles with a powerful laser. The ATL system was to be installed on a heavily armed ground support aircraft. An airborne laser (ABL) is a demonstration of the U.S. Air Force of a high-energy laser system designed to destroy missiles on their boost phase. Over 30 years and several tens of billions of dollars were expended to develop the systems. Unfortunately, all onboard laser development programs have been closed.Experience of the flying laboratories is realized by Cessna Citations and Falcon 10s planes and is relevant, as it gives the chance to estimate adverse effects of aero-optics and vibrations directly in flight.Among the problems that need to be solved when creating adaptive optics for an onboard laser, the following are highlighted:- loss of compensation capabilities;- thermal effects of laser radiation on optical elements;- creation of attenuators and radiation couplers;- mitigating the negative effects of the onboard platform on radiation;- operation reliability of the actuators of correction devices;- technological working off of the uncooled optical elements which are affected by powerful laser radiation.For newly developed aviation-based laser systems, it is necessary to envision the niche in which their use will be most efficient.
Linear Differential Operators Invertible in the Integro-differential Sense
Authors: Chetverikov V. N. 
Published: January 2020

The paper studies linear differential operators in derivatives with respect to one variable. Such operators include, in particular, operators defined on infinite prolongations of evolutionary systems of differential equations with one spatial variable. In this case, differential operators in total derivatives with respect to the spatial variable are considered. In parallel, linear differential operators with one independent variable are investigated. The known algorithms for reducing the matrix to a stepwise or diagonal form are generalized to the operator matrices of both types. These generalizations are useful at points, where the functions, into which the matrix components are divided when applying the algorithm, are nonzero.In addition, the integral operator is defined as a multi-valued operator that is the right inverse of the total derivative. Linear operators that involve both the total derivatives and the integral operator are called integro-differential. An invertible operator in the integro-differential sense is an operator for which there exists a two-sided inverse integro-differential operator. A description of scalar differential operators that are invertible in this sense is obtained. An algorithm for checking the invertibility in the integro-differential sense of a differential operator and for constructing the inverse integro-differential operator is formulated.The results of the work can be used to solve linear equations for matrix differential operators arising in the theory of evolutionary systems with one spatial variable. Such operator equations arise when describing systems that are integrable by the inverse scattering method, when calculating recursion operators, higher symmetries, conservation laws and symplectic operators, and also when solving some other problems. The proposed method for solving operator equations is based on reducing the matrices defining the operator equation to a stepwise or diagonal form and solving the resulting scalar operator equations.
The relationship between TFP and innovation performance: evidence from EU regions
Authors: Kijek Tomasz , Matras-Bolibok Anna 
Published: January 2020

Research background: Total factor productivity (TFP) determines how efficiently and intensely the available inputs are used and combined in production process. Improvement of TFP performance requires identification of its determinants, thus enabling policy actions to focus on them. Since the ability to create and absorb innovation is considered as a crucial factor of economic development, the investigation of the impact of the level of regional innovative performance on TFP distribution across EU regions is an important research problem.
Purpose of the article: The aim of the paper is twofold. Firstly, we attempt to develop a theoretical framework for the analysis of the impact of innovation on TFP. Secondly, we assess TFP levels for regions in the EU and investigate whether innovations account for the observed regional disparities in TFP.
Methods: The research sample consists of 202 European Union (EU) regions at NUTS 1 and NUTS 2 level from 22 countries. The regional data on GDP, employment and gross fixed capital formation come from the Eurostat. The source of data on the level of innovativeness of European regions is the Regional Innovation Scoreboard. To calculate TFP, we use the multiplicatively-complete Färe-Primont index. In turn, to examine the impact of innovation on TFP, we employ the spatially-lagged X model.
Findings & Value added: Our findings show a high degree of dispersion in TFP across EU regions. We find a positive impact of regional innovation performance on TFP. Although theoretical papers on economic development and regional economics suggest that improvements in TFP are key to regional economic performance, and that innovations are crucial to gain such productivity effects, there is a dearth of empirical studies on the link between innovation and TFP at the regional level. Therefore, our paper attempts to fill this gap by providing the evidence of positive effect of innovation externalities on TFP in European regions.
Energy engineering students on their way to expertise in sustainable energy
Authors: Malkki Helena , Alanne Kari , Hirsto Laura 
Published: January 2020

Abstract
Energy engineering is facing new challenges in educating experts in sustainable energy. The aim of this paper is to characterise expertise related to sustainability in higher education. Future challenges and required skills are explored through recent studies, which have listed key competencies that engineers need in their working life. Sustainability and expertise are discussed on the basis of literature and energy curricula are explored on universities’ internet pages.
The quality of pellets available on the market in Latvia: classification according en 14961 requirements
Authors: Kirsanovs Vladimirs , Timma Lelde , Zandeckis Aivars , Romagnoli Francesco 
Published: January 2020

Abstract
The objectives of the paper are to determine the quality of pellets available on the market in Latvia and to compare results with the European standard EN 14961-2:2011. The following parameters have been determined for samples of pellets: length, diameter, moisture and ash content, mechanical durability, lower calorific value and bulk density. The results showed that all samples confirm to the B class requirements of the standard. If one considers the A1 class - only 4 out of 9 samples fit the requirements. The paper emphasizes the need for the introduction of a quality control system for the wood pellets market in Latvia.
An Integrated Model to Optimize Artificial Islands Developments in Shallow Water Fields
Authors: Alnaseef Faisal H. , Almedallah Mohammed K. , Clark Stuart R. , Walsh Stuart D. C. 
Published: January 2020

Artificial Islands are often an effective strategy to develop shallow-water fields. However, their layout and design are affected by numerous drilling and surface facility constraints, such as water depth, number of wells, proximity to shore, and well spacing. When these constraints cannot be honored, conventional offshore wellhead platforms must be installed instead. This paper reviews previous artificial island projects to identify their key constraints, and then proposes a numerical model that accounts for these constraints when determining whether artificial islands or offshore platforms would generate the highest Net Present Value (NPV) configuration.
The model uses a combination of discrete and continuous mathematical algorithms to find the optimum development plan in shallow-water fields. Specifically, the model analyses the water depth, drilling and surface facilities of the field to suggest the optimum facility type to drill the wells using a k-means algorithm and Mixed-Integer Linear Programming (MILP). Then, a local optimization routine is used to connect islands to well targets. The model accounts for limitations on well spacing and the well paths to ensure that wells conform to the available drilling-rig capabilities and well-pad design requirements. The overall field configuration is optimized using a stochastic-perturbation method that adjusts the field network to maximize the NPV of the development.
The model explores the numerous possible scenarios that exist when planning shallow-water offshore field developments, especially when a high number of wells is required. The coupling of continuous and discrete optimization techniques provides a quick and effective method to analyze these possible scenarios and select an optimal strategy. Results from the model indicate that offshore wellhead platforms are not always favored over artificial islands in offshore field developments, particularly when extended reach wells are present. This is illustrated with a case study that demonstrates each stage in the integrated model starting from the analysis of the reservoir simulation model, through to well planning, and design of the facility network. The study highlights how such integrated analysis can aid in the selection of the highest development NPV plan in shallow-water fields by not only minimizing the cost associated with the development but also reducing the time required to generate the optimum plan.
Acid Stimulation-Best Practices for Design, Selection and Testing of Acid Recipes in Low Permeability Carbonate Reservoirs
Authors: Hall-Thompson Bryan , Ernesto Arias Rommel , Abdulrahman Nutaifi , Alsuhaimi Abdulaziz 
Published: January 2020

Acid stimulation in low permeability carbonates is challenging and the performance depends on a good choice of acid recipe and comprehensive testing that supports the extent of wormholes or fracture patterns. In this paper, a comprehensive testing proposal that involves initial enhancements to reaction kinetic for organic, inorganic and composite recipes and later supported by core tests to quantify optimized pore-volume to breakthrough (PVBT) times for optimum worm-hole propagation is discussed. A protocol is demonstrated that outlines important tests, analysis and recommended practices to select efficient acid recipes for enhanced stimulation performance in low permeability carbonate reservoir. This protocol demonstrates that the design of efficient acid recipes should take into consideration: rock characteristics, lithological distribution, mineralogy, petrophysical qualities and petrographic information.
A summary of tests, procedures and success criteria demonstrates the benefits of an integrated testing approach prior to deploying acid stimulation. Outlined in this work are important tests, analysis and recommended practices to select efficient acid recipes for enhanced stimulation performance specifically high rate matrix acidization (HRMA) in low permeability carbonate reservoir. These recommendations demonstrate the benefits of an integrated procedure for achieving superior well productivity, costs savings, operational flexibility and long term applicability that addresses subsurface and operational requirements for acid stimulation. This system is considered in offshore environments where logistics and cost are important in designing a stimulation strategy and is also applicable to onshore environments.
Some key findings are that under simulated reservoir conditions and similar rock properties chemical or/and physical retarded acid provided deeper wormhole results from PVBT point of view than straight acid. Viscoelastic aicd (VES) diverter acid on the other hand showed deeper penetration by lower PVBT which will demonstrate efficiency based on the viscosity. The increase in viscosity could increase bottomhole (BH) pressure limiting matrix regime applications. Three Single Phase Retarded Acids (SPRA) were tested and all demonstrated excellent wormhole penetrations and improved benefits in terms of offshore logistics due to their reduced volumes, reduced viscosity and environmental benefits.
Does Financial & Social Development are Important for Economic Growth? An International Scenario
Authors: Abdul Rehman  , Irum Saba  , Rehana Kousar  
Published: January 2020

Financial and Social Development plays pivotal role in the economic growth of nations. Developed countries have strong financial and social infrastructure. This study focuses on the social and financial development in relation to economic growth of developed, developing and frontier economies. Gross Domestic product (GDP) per capita used as dependent variable. Domestic credit, market capitalization, turnover ratio, household consumption, foreign direct investment, capital formation, Co2 Emission and trade openness are used as independent variables. government expenditures on education and current health expenditures are use as social variables. Unemployment and inflation rate also use as control variables. Pooled OLS (ordinary least squares), fixed effects and random effects models are used to check the relationship among variables from 2001-2017. Results show positive and significant relation between Gross Domestic product (GDP) Domestic credit, education expenditures and health expenditures in case of developing countries. Market capitalization, turnover ratio, foreign direct investment, and trade openness have a positive but insignificant relationship. Co2 Emission, inflation and unemployment rate have negative and insignificant relation with GDP per capita. In advanced countries Inflation rate trade openness and FDI have positive and significant relation with GDP per capita. Domestic credit, market capitalization, turnover ratio, household final consumption and Co2 Emission have a negative relation with GDP per capita. Education and health also have a negative and insignificant relation with GDP per capita. In Frontier economies there is a positive and insignificant relation of market capitalization, FDI, Co2 Emission and health expenditures with GDP per capita. capital formation, turnover ratio, household consumption, trade openness has negative and significant relation with per capita. Education expenditures have positive and significant relation with GDP per capita. Co2 have positive but insignificant relation. Inflation and unemployment rate have negative but insignificant relation with GDP per capita.
Активный вариант синдрома кандинского-клерамбо при шизофрении
Authors: Asadov B.M. 
Published: January 2020

В последние годы появился ряд исследований, посвященных изучению осо­бен­ностей становления, формирования, психопатологического строения и специфической но­зо­логической окраски синдрома Кандинского-Клерамбо [1; 2; 6; 9 и др.]. Однако, анализ психиатрической литературы показывает, что большинство исследований проведено в плане расширения нозологических форм психозов, в рамках которых встречается синдром Кандинского-Клерамбо, нежели в плане глубокого клинико-психопатологического исследования этого сложного психопатологического состояния. В то же время, в структуре самого синдрома обнаруживаются психопатологические особенности, не ставшие еще предметом специального исследования.
Актуальность исследования. В последние годы появился ряд исследований, посвященных изучению осо­бен­ностей становления, формирования, психопатологического строения и специфической но­зо­логической окраски синдрома Кандинского-Клерамбо [1; 2; 6; 9 и др.]. Однако, анализ психиатрической литературы показывает, что большинство исследований проведено в плане расширения нозологических форм психозов, в рамках которых встречается синдром Кандинского-Клерамбо, нежели в плане глубокого клинико-психопатологического исследования этого сложного психопатологического состояния. В то же время, в структуре самого синдрома обнаруживаются психопатологические особенности, не ставшие еще предметом специального исследования.
Correlation Between Nutrition Status and Lipid Profile Toward Sexual Satisfaction on Perimenopause Women in Working Area Public Health Centre (PHC) of Bara-Baraya
Authors: Jumrah Jumrah , Rosdianah Rosdianah , Sabar Syamsuriyana , Lestari Ayu , Ningsih Julia Fitria 
Published: January 2020

Premenopausal woman is a physiological state that has entered the aging process, which is characterized by decreased ovarian estrogen production. In conditions of estrogen deficiency often arise various debilitating syndrome called premenopausal syndrome women. This study aims to determine the relationship of nutritional status and lipid profile to sexual satisfaction in perimenopausal women. This study used cross-sectional study. The sample in this study is partly perimenopausal women in Puskesmas Bara-baraya total of 37 respondents. Data analysis used chi-square test with Î± = 0.05. It is shown that there was no relationship always connects two things of nutritional status based on BMI (Ï = 0.347).However, the relationship is shown based on the circumference of the abdomen showed a link (Ï = 0.048). Based on cholesterol for the status of lipid, it is shown that there is no association with sexual satisfaction (Ï = 0.006), while based triglycerides, it showed no correlation as well (Ï = 0.571).
The Analysis of The Incidence of Depression and Risk of Suicide Using Buddy App on Teenagers in Makassar
Authors: Sari Mutmainnah , Arbianingsih Arbianingsih , Amal A. Adriana 
Published: January 2020

The data from the World Health Organization in 2017, suicidal behavior of teenagers Indonesia of 13-17 years old, as many 5.6% teens had made plans related to the way they committed suicide. The aim of this research is to find out the analysis of the incidence of depression and risk of suicide using Buddy App on teenagers in Makassar. This research was an analytic quantitative with cross-sectional study approach. As many 285 teenagers involved in this research recruited by simple random sampling. Data collected by using a of depression namely KADS that are provided through online form and questionnaire of risk of suicide, namely CSSRS using buddy apps. It is called Buddy App because of its function as an application that can be a close friend to users. The incidence of depression and risk of suicide is higher in the late adolescents. Mean of depression in early adolescent (4.78) and late adolescent (6.31). The statistical test results showed the significant differences between the incidence of depression (p-value 0,000) and the level of risk of suicide (p-value 0,022) in early adolescence and late adolescents. The next researcher is expected to examine the level of depression in each level of suicide risk by developing the questionnaire of depression.