bluuebunny/crossref_metadata_2025 huggingface dataset:
Adoção do papel, ansiedade, depressão e solidão em cuidadores familiares de pacientes com doenças crônicas
Authors: Carreño-Moreno Sonia , Pacheco-López Mario , Arias-Rojas Mauricio
Published: June 2024

Objetivo: descrever e explorar a relação entre a solidão, a ansiedade e a depressão com a adoção do papel de cuidador entre os indivíduos que cuidam de pessoas com doenças crônicas na Colômbia. Método: trata-se de um estudo exploratório e transversal que envolveu 960 cuidadores primários de indivíduos com doenças crônicas. Foi aplicada a Escala de Adoção do Papel de Cuidador, a Escala de Solidão da Universidade da Califórnia em Los Angeles e a Escala de Ansiedade e Depressão. Foram realizadas análises de componentes principais e de correspondência múltipla para o agrupamento. Resultados: entre os cuidadores participantes, 40,8% relataram ter depressão, 59% relataram ansiedade, 54,6% relataram solidão moderada a grave e 88,6% relataram uma adoção satisfatória do papel de cuidador. Os cuidadores que apresentaram níveis básicos ou insuficientes de adoção do papel tenderam a ter pontuações mais elevadas de ansiedade, depressão e solidão. Conclusão: a adoção do papel de cuidador é um mediador nos níveis de ansiedade, depressão e solidão entre os cuidadores. As estratégias destinadas a apoiar os cuidadores devem incluir o treinamento para o papel de cuidador, a fim de atenuar os impactos negativos da ansiedade, da depressão e da solidão.
Integrative taxonomy of the black-barred disk pacus (Characiformes: Serrasalmidae), including the redescription of Myloplus schomburgkii and the description of two new species
Authors: Machado Valéria N. , Pereira Victória D. , Ota Rafaela P. , Collins Rupert A. , Ândrade Marcelo , Garcia-Ayala James R. , Jégu Michel , Farias Izeni P. , Hrbek Tomas
Published: June 2024

Abstract Presently, Myloplus schomburgkii is the most easily recognized species among the serrasalmids by having a vertical black bar in the middle of the body. However, through a broad taxonomic review, including DNA barcoding and morphological analyses, we were able to identify and describe two new species that also share a dark vertical bar on the flank. In addition, we redescribe M. schomburgkii, designating a neotype and restricting the type-locality to rio Negro in Barcelos, Amazonas State, Brazil. The three lineages of black-barred pacus present high molecular divergences (7.9–11%) and can be distinguished by differences in the shape of the vertical bar, shape of females’ anal fin, number of total vertebrae, number of total branched dorsal-fin rays, among other characters. Although the existence of these two new species has been hidden due to many morphological similarities, mainly the presence of the black bar, the three lineages do not compose a monophyletic group, with one of the new species being recovered as sister to Ossubtus xinguense. This result reinforces the necessity of the redefinition of the Myleini genera.
Identification and Attribution of Blame in Rape Situations by University Students
Authors: Pagel Wesley Henrique , Laurenti Carolina , Macerau Walkiria Maria de Oliveira , Machado Isadora Vier
Published: June 2024

Abstract Although society criminalizes rape, many institutions reproduce stereotypes of this sexual assault. Rape can also occur in the university and in various ways that do not correspond to its stereotypes. The article aimed to evaluate how undergraduates identify situations of rape and how they attribute fault to the victim and the aggressor. 228 participants commented on fictional stories of rape that manipulated the variables: sexual assault with or without penetration; previous behavior of the victim; previous relationship between the characters; and presence or absence of physical strength in the rape. The results showed that these variables influence the identification of rape and that male students tend to blame victims more than female students. Understanding the multiple variables that affect identification and attribution of blame can lead to more effective sexual violence prevention and intervention strategies.
Jair Messias Bolsonaro e suas verdades: o negacionismo da Ditadura Civil-Militar em três proposições legislativas
Authors: Bauer Caroline Silveira
Published: June 2024

Resumo O negacionismo histórico da Ditadura Civil-Militar Brasileira de 1964 esteve presente ao longo de toda a carreira política de Jair Messias Bolsonaro. Este artigo analisa três proposições relacionadas à Ditadura de 1964 apresentadas por Bolsonaro durante seus mandatos legislativos em 2004, 2013 e 2014. Objetiva-se explicitar a historicidade e as características do negacionismo presentes nessas propostas, argumentando que essa negação atualiza as estratégias de implantação do terror da Ditadura no fomento a uma cultura do medo, e, com isso, promovendo a violência. Dessa forma, é possível reconhecer o negacionismo histórico além de uma mera negação da realidade.
O NOVO PNE E O ARCABOUÇO FISCAL: MÍNIMO CONSTITUCIONAL E META DE FINANCIAMENTO DA EDUCAÇÃO EM RISCO
Authors: Sala Mauro , Piolli Evaldo
Published: June 2024

Este artigo discute a meta para o financiamento do próximo Plano Nacional de Educação 2024-2034, proposta pela CONAE-2024, à luz das atuais regras fiscais do Estado brasileiro. Assim, este artigo discutirá o chamado novo arcabouço fiscal, instituído pela Lei Complementar 200/2023, e como ele constrange a expansão das despesas primárias e, consequentemente, as despesas públicas em educação. A conclusão que chegamos, tanto pela leitura atenta das regras fiscais quanto pelas projeções feitas pelo Tesouro Nacional e pelo próprio executivo, é que o quadro fiscal imposto pelo novo arcabouço fiscal inviabilizará a expansão do financiamento público para a educação pública no próximo decênio, colocando em risco até o dispositivo constitucional que estabelece um piso para o investimento da União, estados, distrito federal e municípios na educação pública. Desse modo, para a realização do próximo PNE e para a manutenção do mínimo constitucional, precisamos colocar em questão a própria regra fiscal que os inviabilizam.
Flora of Ceará: Siparunaceae
Authors: Brunassi Gustavo , Lirio Elton John de
Published: June 2024

The present work deals with the family Siparunaceae in the state of Ceará, Brazil. The family comprises 53 species in two genera, Siparuna Aubl. of Neotropical distribution and Glossocalyx Benth (monotypic) occurring in Western Africa. In Brazil, Siparunaceae is represented by the genus Siparuna with 20 species, with the Amazon as its center of diversity with 19 species, followed by the Atlantic Forest with seven species, and Cerrado with six. In Ceará, two species are mentioned in the Flora of Brazil 2020, namely, Siparuna guianensis and Siparuna reginae. This work was based on the examination of physical and virtual herbarium material, types and bibliographies. Two species of Siparuna were recorded for the state of Ceará, S. guianensis and S. brasiliensis, the second being a new occurrence for the state. A geographic distribution map of the species, an identification key, photographs, taxonomic descriptions, and taxonomic comments are provided.
Assessment of Turkish airport performances via two-phase models based on common weights
Authors: Pehlivanli Edib Ali , Özsoy Volkan Soner
Published: June 2024

Data envelopment analysis (DEA) is a widely used strategic performance management tool to evaluate airport performance. However, earlier studies have identified shortcomings in DEA. The first is using conventional DEA models for single-phase modelling of intricate structures like airports. The second is that when DEA calculates efficiency scores, some important aspects are ignored with zero weights. The purpose of this study is to determine whether a minimax two-phase DEA model can address these issues in performance evaluations of complex units like airports by achieving more consistent efficiency scores and ranks. To evaluate airport performance, two models are compared: the minimax two-phase DEA model based on common set of weights (CSWs) and the common multiplicative two-phase DEA model. Data from 42 Turkish airports covering the years 2014–2019 are analysed for this purpose. The two phases of an airport model are flight infrastructure and flight consolidation. The results demonstrate that more consistent rankings and efficiency scores are obtained when the minimax two-phase DEA model based on CSW is used. The study highlights the model's benefits for strategic performance evaluation and offers recommendations for policymakers and airport engineers regarding further investments.
Serum and Urine Metabolites and Kidney Function
Authors: Yeo Wan-Jin , Surapaneni Aditya L. , Hasson Denise C. , Schmidt Insa M. , Sekula Peggy , Köttgen Anna , Eckardt Kai-Uwe , Rebholz Casey M. , Yu Bing , Waikar Sushrut S. , Rhee Eugene P. , Schrauben Sarah J. , Feldman Harold I. , Vasan Ramachandran S. , Kimmel Paul L. , Coresh Josef , Grams Morgan E. , Schlosser Pascal
Published: June 2024

Key Points

We provide an atlas of cross-sectional and longitudinal serum and urine metabolite associations with eGFR and urine albumin-creatinine ratio in an older community-based cohort.

Metabolic profiling in serum and urine provides distinct and complementary insights into disease.

Background

Metabolites represent a read-out of cellular processes underlying states of health and disease.

Methods

We evaluated cross-sectional and longitudinal associations between 1255 serum and 1398 urine known and unknown (denoted with “X” in name) metabolites (Metabolon HD4, 721 detected in both biofluids) and kidney function in 1612 participants of the Atherosclerosis Risk in Communities study. All analyses were adjusted for clinical and demographic covariates, including for baseline eGFR and urine albumin-creatinine ratio (UACR) in longitudinal analyses.

Results

At visit 5 of the Atherosclerosis Risk in Communities study, the mean age of participants was 76 years (SD 6); 56% were women, mean eGFR was 62 ml/min per 1.73 m2 (SD 20), and median UACR level was 13 mg/g (interquartile range, 25). In cross-sectional analysis, 675 serum and 542 urine metabolites were associated with eGFR (Bonferroni-corrected P < 4.0E-5 for serum analyses and P < 3.6E-5 for urine analyses), including 248 metabolites shared across biofluids. Fewer metabolites (75 serum and 91 urine metabolites, including seven metabolites shared across biofluids) were cross-sectionally associated with albuminuria. Guanidinosuccinate; N2,N2-dimethylguanosine; hydroxy-N6,N6,N6-trimethyllysine; X-13844; and X-25422 were significantly associated with both eGFR and albuminuria. Over a mean follow-up of 6.6 years, serum mannose (hazard ratio [HR], 2.3 [1.6–3.2], P = 2.7E-5) and urine X-12117 (HR, 1.7 [1.3–2.2], P = 1.9E-5) were risk factors of UACR doubling, whereas urine sebacate (HR, 0.86 [0.80–0.92], P = 1.9E-5) was inversely associated. Compared with clinical characteristics alone, including the top five endogenous metabolites in serum and urine associated with longitudinal outcomes improved the outcome prediction (area under the receiver operating characteristic curves for eGFR decline: clinical model=0.79, clinical+metabolites model=0.87, P = 8.1E-6; for UACR doubling: clinical model=0.66, clinical+metabolites model=0.73, P = 2.9E-5).

Conclusions

Metabolomic profiling in different biofluids provided distinct and potentially complementary insights into the biology and prognosis of kidney diseases.
Gender Differences in the Relationship between Dating-Violence Victimization and Suicidality in Youths
Authors: A Lebimoyo Azizat , O Sanni Mumtaz
Published: June 2024

Context: Dating violence is prevalent in romantic relationships between young adults, and may be linked with suicidal ideation and behavior in victims. However, the pattern of dating violence victimization, suicidality, and the relationship between dating violence victimization and suicidality could vary depending on gender. Aims: To determine gender differences in the relationship between dating violence victimization and suicidality in young adults. Settings and Design: Cross-sectional descriptive study of 118 students (66 Females, 52 Males) between the ages of 18-32 years at a College of Medicine in Lagos, Nigeria. Methods and Material: Study instruments used include; the Dating Violence Questionnaire (DVQ), Suicide Behavior Questionnaire-Revised (SBQ-R), and a Socio-Demographic Questionnaire. Participants were chosen through the convenience sampling method. Statistical Analysis: The Statistical Package for the Social Sciences Version-23 (SPSS version-23) was used to analyze the data. Results: Females who had experienced victimization from their romantic partners in the form of emotional punishment (P=0.02), humiliation (P=0.01), sexual abuse (P=0.03), and gender-based abuse (P=0.01), had significantly higher levels of suicidality compared to males. Conclusion: Gender has a major influence on the expression of suicidality in young adult victims of dating violence.
THE ROLE OF ELECTRONIC RESOURCES IN IMPROVING THE QUALITY OF EDUCATION FOR SCHOOLCHILDREN
Authors:   Osh State University, Abdimalik kyzy Zharkynay , Umarbaeva Zulaika ,   Kyrgyz State Academy of Physical Education and Sports named after BT Turusbekov, Manapbek kyzy Nuriza ,   Osh State University
Published: June 2024

This article examines the issues of improving the quality of educational achievements of students, analyzes information technologies, including electronic textbooks and teaching aids, their place and impact on the quality of school education. To teach students using new information technologies, it is important to involve competent teachers trained in universities specifically on new information technologies. It is necessary to bring the teacher training system to the proper level so that in the future they can prepare electronic textbooks, project presentations, test and study assignments using new information technologies. The use of electronic resources allows you to carry out your plans, make the lesson more effective than using traditional methods. The use of information technology in education affects the growth of professional competence of teachers, contributes to a significant improvement in the quality of education. The study proved that providing high-quality education and upbringing of schoolchildren is possible only through high-level training of pedagogical specialists in the use of electronic manuals.
Measuring Bank Credit Supply Shocks Using the Senior Loan Officer Survey
Authors: Cavallo Michele , Morelli Juan , Zarutskie Rebecca , Baylor Solveig
Published: June 2024

Estimating the effects that bank credit supply has on macroeconomic activity has long been an area of active research. A key challenge in pursuing this goal is the ability to measure such shocks to banks' supply of credit separately from shocks to borrowers' demand for credit.
Unpacking the Effects of Bank Credit Supply Shocks on Economic Activity
Authors: Cavallo Michele , Morelli Juan , Zarutskie Rebecca
Published: June 2024

In this note, we examine the effects of bank credit supply shocks on real economic activity. First, we estimate how GDP and various aggregate demand sectors respond to such shocks. Second, based on the estimated responses, we compute how much those sectors contribute to the overall response of aggregate demand to bank credit supply shocks.
The influence of technological parameters of the laser engineered net shaping process on the quality of the formed object from titanium alloy VT23
Authors:   Peoples' Friendship University of Russia named after Patrice Lumumba, Moscow, Russian Federation, Bazaleeva Ksenia , Safarova Daria ,   Peoples' Friendship University of Russia named after Patrice Lumumba, Moscow, Russian Federation, Ponkratova Yulia ,   Peoples' Friendship University of Russia named after Patrice Lumumba, Moscow, Russian Federation, Lugovoi Maxim ,   Peoples' Friendship University of Russia named after Patrice Lumumba, Moscow, Russian Federation, Tsvetkova Elena ,   Peoples' Friendship University of Russia named after Patrice Lumumba, Moscow, Russian Federation, Alekseev Andrei ,   Peoples' Friendship University of Russia named after Patrice Lumumba, Moscow, Russian Federation, Zhelezni Mark ,   Peoples' Friendship University of Russia named after Patrice Lumumba, Moscow, Russian Federation, Logachev Ivan ,   The National University of Science and Technology MISIS, Moscow, Russian Federation, Baskov Fedor ,   The National University of Science and Technology MISIS, Moscow, Russian Federation
Published: June 2024

Introduction. Laser engineered net shaping (LENS) or Direct metal deposition (DMD) is considered as a promising method for manufacturing products of complex configurations from titanium-based alloys, as it allows minimizing the use of machining and loss of material to waste. Currently, neither the LENS technological process of titanium alloy VT23 has not been developed, nor the structural features of the alloy after LENS have not been studied, which will make it possible to determine the scope of application of the material after LENS. The purpose of this study is to determine optimal modes of the LENS process for manufacturing of quality parts from titanium alloy VT23. Methodology. The alloy specimens obtained with laser power 700÷1300 W in increments of 100 W and scanning speed 600÷1,000 mm/min in increments of 200 mm/min and distance between adjacent laser tracks 0.5–0.9L (L — track width) in increments of 0.2L were analyzed in the study. The elemental composition of the powder material was studied by X-ray fluorescence analysis and reducing combustion in a gas analyzer, the structure of the objects obtained by LENS was analyzed by metallographic and X-ray phase analysis methods as well as microhardness was determined. Results and discussion. It is established that high-quality objects without cracks, with low porosity can be synthesized from VT23 alloy by LENS method using the following modes: laser power 700÷1100 W, scanning speed 800–1,000 mm/min, track spacing 0.5–0.7 of the individual track width L. It is shown that after all investigated LENS modes, the VT23 alloy had a dispersed (α+β) structure of the “basket weave” type. It is revealed that regardless of LENS mode the amount of β-phase in the alloy structure is about 30 %. It is shown that the microhardness of the deposited material does not depend on LENS modes and is 460 HV.
Oxidation temperatures of WC-Co cemented tungsten carbides
Authors:   Tyumen Industrial University, Russian Federation, Efimovich Igor , Zolotukhin Ivan ,   Tyumen Industrial University, Russian Federation
Published: June 2024

Introduction. Products containing WC-Co cemented tungsten carbides are commonly used in various industries. It is often operates at elevated temperatures, at which, as noted in the literature, tungsten carbides are susceptible to severe oxidation in air. However, no sufficiently accurate values of oxidation temperatures and dependence of these temperatures and the oxidation rate of tungsten carbides on the cobalt content with its wide variation have been established. The subject of the study is the oxidation process of WC-Co cemented tungsten carbides. The purpose of the work is to obtain the oxidation temperatures of WC-Co cemented tungsten carbides with different cobalt content by weight in the range of 3–20 %. Methods. The dynamics of oxidation was studied in air. Specimens of the same length were heated to a temperature of 850 °C and cooled at the same rate in the furnace of a push-rod dilatometer Netzsch 402 PC while its expansion was simultaneously recorded. The oxidation rate of the specimens was determined by the difference in its length before heating and after cooling. The values of oxidation temperatures were obtained by mathematical analysis of relationships of the expansion on temperature. Results and discussion. Experimental dependences of expansion of WC-Co cemented tungsten carbides on temperature in the range from 20 to 850 °C, and for WC-8Co – up to 1,150 °C, were obtained. The oxidation rate of WC-Co cemented tungsten carbides increased linearly with increasing concentration of tungsten carbides (decreased with increasing cobalt content). During heating, two characteristic temperatures were identified: the onset of oxidation (631±4 °C) and the transition to active oxidation (804±11 °C). The established temperatures were the same for different ratios of tungsten carbides and cobalt. The results can be used when choosing temperature conditions for products made from WC-Co cemented tungsten carbides.
Preparation of coatings with high infrared emissivity
Authors:   Belgorod State Technological University named after V.G. Shukhov, Russian Federation, Sirota Vyacheslav , Zaitsev Sergey ,   Belgorod State Technological University named after V.G. Shukhov, Russian Federation, Limarenko Mikhail ,   Belgorod State Technological University named after V.G. Shukhov, Russian Federation, Prokhorenkov Dmitry ,   Belgorod State Technological University named after V.G. Shukhov, Russian Federation, Lebedev Mikhail ,   Belgorod State Technological University named after V.G. Shukhov, Russian Federation, Churikov Anton ,   Belgorod State Technological University named after V.G. Shukhov, Russian Federation, Dan'shin Alexey ,   JSC “Shebekinsky Machine-Building Plant”, Russian Federation
Published: June 2024

Introduction. One of the promising modern methods of coating formation is detonation gas dynamic sputtering. Coatings obtained by this method have high adhesion to the substrate, dense structure and specified functional properties. Development of technology for obtaining functional coatings with high emission coefficient in the infrared range is an urgent need for the development of high-temperature industrial processes and technologies. High-temperature industrial processes consume a large amount of energy, so improving the energy efficiency of industrial equipment is considered as one of the ways to overcome the ever-growing energy crisis. To this end, coatings with high infrared emissivity have been developed for industrial furnaces. These coatings are usually applied to the furnace walls, which significantly improves energy efficiency by increasing heat transfer from the heat-emitting surfaces of the furnace. The purpose of the work is to obtain coatings with high emission indices in the infrared range for further recommendation of its use in baking ovens of Shebekinsky machine-building plant. Methods for studying coating specimens obtained by detonation gas-thermal method: scanning electron microscopy, X-ray phase analysis, energy dispersive analysis, infrared spectroscopy. Results and discussion. The microstructure, phase composition, emissivity and thermal cycling resistance of Fe2O3; Al2O3 + 10 % Fe2O3; Ti + 10% Fe2O3 coatings obtained by detonation gas-dynamic powder spraying are investigated in this work. The results of the study showed that the obtained coatings have a dense structure, increased emissivity and resistance to thermal treatment cycles, as a result of which the structure of the crystal lattice of the coatings does not change.
The effect of laser surfacing modes on the geometrical characteristics of the single laser tracks
Authors:   Novosibirsk semiconductor device plant Vostok, Russian Federation, Dolgova Svetlana , Malikov Alexandr ,   Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russian Federation, Golyshev Alexander ,   Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russian Federation, Nikulina Aelita ,   Novosibirsk State Technical University, Russian Federation
Published: June 2024

Introduction. Laser surfacing is one of the leading trends in the field of additive technologies, which consists in layer-by-layer build of material using a laser as an energy source. To obtain a high-quality product, it is necessary to select the optimal building parameters correctly. The problem is that such optimization is necessary for all equipment, since minor differences in its characteristics can make significant changes in the parameters of layer-by-layer build. In order to determine the optimal build mode, it is enough to analyze the effect of various equipment parameters on the characteristics of single tracks. Therefore, the purpose of this work is to determine the most important parameters of laser radiation that affect the surfacing process and the optimal mode for building a single track of chromium-nickel steel. The work investigated single tracks obtained by laser surfacing of powder from austenitic chromium-nickel steel AISI 316L. The optimization factors included such characteristics as laser power, beam speed, flow rate of supplied powder and laser spot size. The wavelength of laser radiation was 1.07 μm. Research methods. To determine the quality and geometric dimensions of single tracks, the macrostructure of cross sections of specimens was studied using metallography and scanning electron microscopy methods. Results and discussion. It is established that the optimal mode for growing single tracks of steel AISI 316L is characterized by a laser radiation power of 1,250 W and a scanning speed of 25 mm/s. In this case, the optimal powder consumption rate is 12 g/min, and the laser spot size is 4.1 mm. The work shows that the powder consumption and laser spot size have the greatest influence on the coefficient of effective use of powder material. By changing it, the surfacing performance can be increased by 10–15 %.
Investigations on ultrasonic vibration-assisted friction stir welded AA7075 joints: Mechanical properties and fracture analysis
Authors:   Vishwakarma Institute of Information Technology, Maharashtra, India, Gaikwad Vaibhav , Chinchanikar Satish ,   Vishwakarma Institute of Information Technology, Maharashtra, India
Published: June 2024

Introduction. Joint efficiency and strength, particularly in aluminum alloys, are crucial in aerospace, defense, and industrial applications. Post-welding treatments like shot peening and laser shock peening significantly improve joint efficiency and strength, enhancing fatigue life, grain structure, and tensile strength. The purpose of the work. The literature reviewed shows that the ultrasonic vibration-assisted friction stir welding (UVaFSW) and post-weld treatment improved the mechanical properties and material flow. However, limited studies have been observed on the UVaFSW joints of AA7075-T651, considering the consequence of welding speed, tool rotation, and post-weld shot peeing treatment. The methods of investigation. The study investigates the ultrasonic vibration-assisted friction stir welded (UVaFSwed) AA7075-T651 joint's tensile strength, microhardness, microstructure, and fracture behavior, considering the impact of tool rotation, welding speed, and post-weld shot peening treatment. Results and Discussion. The post-weld treated shot-peened UVaFSWed joints demonstrated the maximum tensile strength of 373.43 MPa, the microhardness of 161 HV, and the lowest surface roughness of 15.16 µm at 40 mm/min welding speed when compared to the friction stir-welded (FSWed) joints. These results indicate that shot peening improved the mechanical properties and surface quality of the UVaFSWed joints. The high tensile strength and low surface roughness make these joints suitable for applications requiring strength and aesthetics. The fracture for the shot peened UVaFSWed joints mainly occurred in the heat-affected zone (HAZ) during the tensile test. It could be attributed to the higher temperature experienced during welding, which resulted in grain growth and decreased material strength in the HAZ. The shot-peened UVaFSWed joint has a more uniform grain distribution than the FSWed one, which contributed to the joint's higher tensile strength. The fractured surface of the shot peened UVaFSWed joints showed larger, equiaxed, and shallow dimples, resulting in higher ultimate tensile strength (UTS) and microhardness compared to the conventional FSWed joints. The mechanical properties and microstructure observed in the welding zones of shot peened UVaFSWed joints are superior to those of conventional FSW joints. However, further investigation is required to determine the specific factors contributing to this localized failure at HAZ, considering the effects of shot peening parameters. This study also suggests the potential for optimizing shot peened UVaFSWed joints of AA7075-T651.
Determination of the rate of electrochemical dissolution of U10A steel under ECM conditions with a stationary cathode-tool
Authors:   Novosibirsk State Technical University, Russian Federation, Yanpolskiy Vasiliy , Ivanova Maria ,   Novosibirsk State Technical University, Russian Federation, Nasonova Alexandra ,   Novosibirsk State Technical University, Russian Federation, Yanyushkin Alexander ,   I.N. Ulianov Chuvash State University, Cheboksary, Russian Federation
Published: June 2024

Introduction. In blank production, when replacing hard alloys with tool steels, difficulties arise in shaping surfaces to ensure the required parameters of productivity, quality and accuracy, due to the presence of incomplete information for assigning electrochemical processing modes for this class of materials. This fact requires additional research to determine rational processing modes that provide the necessary technological parameters (productivity, dimensional accuracy and surface roughness). The purpose of the work is to conduct research to establish the patterns of electrochemical shaping of tool steels and determine the modes of the shaping process. The work investigated the features of anodic dissolution of U10A tool steel in an aqueous NaCl solution of 10 % concentration. The range of potential changes was from 0 to 8 V. Technological performance parameters were determined (current output for the main reaction and the rate of electrochemical dissolution at a voltage of 8 V and an electrolyte pressure of 0.1 MPa). Research methods. For polarization studies, a potentiodynamic research method was chosen. Technological experiments were carried out using the model of piercing holes with a stationary cathode-tool made of stainless steel without insulation. A circular cross-section with outer diameters of 0.908 mm and inner diameters of 0.603 mm was chosen as a cathode tool. Results and discussions: it is revealed that the electrochemical dissolution of U10A tool steel in a 10 % aqueous solution of NaCl is active in the studied potential range from 0 to 8 V. The technological experiments carried out made it possible to establish the dimensions of the resulting holes — an average diameter of 1.433 mm and a depth of 0.574 mm. The current efficiency was 70.83 %. Based on the analysis of the experimental data obtained, it is established that in order to ensure high productivity of the process of electrochemical forming of U10A steel in a solution of 10 % NaCl, the feed of the cathode tool should be 0.2232 mm/min, which corresponds to the rate of electrochemical dissolution under the studied forming conditions.
Impact of TLR9 and TLR7 gene polymorphisms on prognosis and survival of patients with oral squamous cell carcinoma
Authors: Obrenović Miroslav , Šupić Gordana , Miyabe Satoru , Mladenović Irena , Kozomara Ružica , Jović Saša , Petković Ćurčin Aleksandra , Štefik Debora , Stosić Srboljub , Vukomanović Đurđević Biserka
Published: June 2024

Despite significant efforts in developing new diagnostic and therapeutic modalities, oral squamous cell carcinomas (OSCCs) still exhibit a high recurrence rate, a low five-year survival rate, and an increasing prevalence. Toll-like receptors (TLRs), which initiate and perpetuate immune mechanisms upon activation, have been linked to immune surveillance and the antitumor immune response. The aim of this study was to investigate the association between the polymorphisms of the TLR7 rs3853839 and TLR9 rs187084 genes and OSCC risk, clinicopathological features, and survival. Genotyping was assessed by real-time polymerase chain reaction (PCR) in 95 HPV negative OSCC patients and 107 age- and sex-matched healthy controls. Patients with lymph node metastases had higher frequencies of the TLR9 rs187084 CC variant genotype compared to the major TT genotype (P = 0.020) and to T-allele carriers (combined TT + CT genotypes, P = 0.015). A higher prevalence of advanced stage III was observed in patients with the TLR9 rs187084 variant CC genotype compared to TT (P = 0.047) and to T-allele carriers (TT + CT, P = 0.037). Kaplan–Meier analysis revealed a lower overall survival (OS) rate in patients with the TLR9 rs187084 variant CC genotype compared to the TT genotype (P = 0.010, log-rank test) and to T-allele carriers (TT + CT genotypes, P = 0.002), though it was not an independent predictor of OS. Both TLR9 rs187084 and TLR7 rs3853839 polymorphisms were associated with high alcohol consumption (P = 0.027 and P = 0.001, respectively). The investigated genetic variations were not associated with OSCC susceptibility. The variant CC genotype of the TLR9 rs187084 polymorphism might be a marker of poor survival and tumor progression in OSCC.
Localization of the E. coli Dps protein molecules in a silicon wires matrix according to scanning electron microscopy and X-ray photoelectron spectroscopy
Authors: Parinova Elena V. , Antipov Sergey S. , Sivakov Vladimir , Belikov Evgeny A. , Chuvenkova Olga A. , Kakuliia Iuliia S. , Trebunskikh Sergey Yu. , Skorobogatov Matvey S. , Chumakov Ratibor G. , Lebedev Alexei M. , Artyukhov Valerii G. , Turishchev Sergey Yu.
Published: June 2024

The work is related to the study of the morphological features of silicon wires arrays combined with a nanomaterial of natural origin, a bacterial ferritin-like protein Dps, and their relationship with the composition of the surface and interior.     A silicon wires array was formed by metal-assisted wet chemical etching. To obtain recombinant protein, Escherichia coli BL21*(DE3) cells were used as producers, and purification was carried out by the chromatography method. The combination of silicon wires with protein molecules was carried out by layering under laboratory conditions, followed by drying. The resulting hybrid material was studied by scanning electron microscopy and X-ray photoelectron spectroscopy.    The initial silicon wires array had sharp boundaries on the surface. The diameter of the silicon wires was about 100 nm, while the distances between the wires can vary widely, reaching several hundred nanometres or be less than 100 nanometres, depending on the formation conditions, in the absence of noticeable transition layers. The pores formed in this way are available for filling with protein during deposition.     The effectiveness of using the scanning electron microscopy method to study the morphology of the hybrid material “silicon wires – bacterial protein Dps” as well as X-ray photoelectron spectroscopy method together with ion etching for the investigation of the composition and physico-chemical of the hybrid material was demonstrated. Complementary results have shown that the molecular culture, which is a solution of oligomers of the recombinant Dps protein of E.coli bacterial cells, can penetrate deep into the pores of the silicon wires array with an extremely developed surface. The possibility of the control of the filling of silicon wires arrays by varying the pore morphology and other modes of formation of structuresand their surface has been demonstrated.      The obtained data can be used to study the possibilities of the functionalization of the developed surface of silicon wires by their driven coating with controlled delivery of biohybrid material.
Influence of UV radiation on the catalytic activity of nanosized cobalt ferrite in the oxidative degradation reaction of dinitrophenol
Authors: Tomina Elena V. , Mai Vo Quang , Kurkin Nikolay A. , Doroshenko Alyona V. , Anh Tien Nguyen , Sinelnikov Alexander A.
Published: June 2024

Due to their multi-functionality, spinel ferrites, both doped and undoped, are promising materials for a wide range of practical applications, including catalysis, sustainable production of hydrogen and СО2 deposition, electronic and magnet devices, as well as antibacterial agents. Recently, nanosized ferrites have been actively tested as catalysts in Fenton-like processes of deep oxidative degradation of organic substances in order to purify waste waters of different dyes, phenol and its derivatives, and antibiotics. The goal of this work was to establish the catalytic activity of СоFe2O4 nanopowder synthesisedusing citrate combustion in the reaction of oxidative degradation of 2,4-dinitrophenol upon the activation of the process with UV radiation.     Using citrate combustion, we synthesised the impurity-free nanopowder of CoFe2O4 cobalt ferrite with the average size of particles of about 70 nm and a pronounced agglomeration of particles. The cobalt spinel was tested as a catalyst of Fentonlike reaction of oxidative degradation of 2,4- dinitrophenol with UV radiation of l = 270 nm. This process was differentiated with the sorption of dinitrophenol on a nanosized catalyst.      The degree of degradation of 2,4-dinitrophenol in a Fenton-like reaction without the CoFe2O4 catalyst was 14 %, while in the presence of a nanosized catalyst it increased up to 80 %. The effective oxidative degradation of the pollutant was performed in a less acidic environment as compared to a classic Fenton process with a rather large initial concentration of dinitrophenol. This allowed considering the nanosized CoFe2O4 as a promising catalyst of Fenton-like of waste waters purification through deep oxidative degradation of toxins.
Phase diagrams of zirconium dioxide systems with yttrium and scandium oxides
Authors: Fedorov Pavel P. , Chernova Elena V.
Published: June 2024

The literature data on the study of phase equilibria in systems zirconia with yttria and scandia are analysed. Possible schemes of low-temperature phase equilibria in ZrO2-Y2O3 and ZrO2-Sc2O3 systems are presented taking into account the third law of thermodynamics.     The coordinates of non-variant transformations in these systems are tabulated. A sign of non-equilibrium states is the observation of non-diffusion processes of ordering of solid solutions. The modified cryoscopy method is used to calculate the distribution coefficients of scandia and yttria during the crystallization of the ZrO2 melt.      The possibilities for the existence of a set of ordered phases in the ZrO2-Y2O3 system and diffuse phase transition in the cubic modification of zirconia are discussed.
A study of the local atomic structure the environment of zinc ions of different concentrations during their interaction with the arachidic acid Langmuir monolayer
Authors: Lysenko Victoria Yu. , Kremennaya Maria A. , Yakunin Sergey N. , Rogachev Alexander V. , Yalovega Galina E.
Published: June 2024

Vital cellular processes depend on the controlled transport of metal ions across biological membranes. A biological membrane is a complex system consisting of lipids and proteins, that is why simplified systems, in particular monomolecular layers, are used to model it.    This work presents the results of a study of the interaction of zinc ions from the aqueous subphase with the Langmuir monolayer of arachidic acid. The study was carried out for the first time and used total external reflection X-ray absorption spectroscopy. It considers the influence of the concentration of a ZnCl2 aqueous subphase solution on the local environment of zinc ions when interacting with the lipid monolayer immediately after its formation.     The theoretical analysis of experimental XANES spectra showed that one of the interaction ways of arachidic acid molecules with zinc ions immediately after the monolayer formation is an intramolecular interaction with the formation of spodium bonds between the zinc cation and the OH carboxyl group of arachidic acid
Features of the molecular composition of dental biofilm in patients depending on the degree of caries and the method of its prevention: synchrotron FTIR spectroscopic studies
Authors: Seredin Pavel V. , Goloshchapov Dmitry L. , Kashkarov Vladimir M. , Buylov Nikita S. , Ippolitov Yury A. , Ippolitov Ivan Yu. , Vongsvivut Jitraporn (Pimm)
Published: June 2024

The article studies the molecular composition of dental biofilm in healthy people and patients with multiple caries lesions during several stages of exogenous and endogenous preventive measures.    The observed changes in the IR spectra registered during different stages of the experiment indicate a lack of balance between demineralisation and mineralisation of hard tissues resulting from different absorption mechanisms of agents applied exogenously and endogenously. All the observed changes result from the difference in the microbiota in healthy patients and patients with caries, as well as the difference in the microbiota caused by the impact of preventive agents on biofilm
Interdiffusion in the formation of thin niobium films on singlecrystal silicon under vacuum annealing conditions
Authors: Afonin Nikolay N. , Logachova Vera A.
Published: June 2024

For the design of technological process for creating device structures based on niobium and single-crystal silicon with thedesired properties, empirical and theoretical knowledge about the solid-phase interaction process in the system of a thin niobium film is required. The purpose of the research was a comprehensive study of the redistribution of components during the formation of thin niobium films on single-crystal silicon obtained by magnetron-assisted sputtering followed by vacuum annealing.    The structure and phase composition were studied by X-ray phase analysis, scanning electron microscopy, and atomic force microscopy. Distribution of components along the depth was determined using the Rutherford backscattering spectrometry.     The traditional experimental method for studying the process of interdiffusion of components in binary macroscopic systems is the placing of inert marks. However, the use of this method in systems containing thin films is hindered by the comparable thicknesses of the films and marks. This circumstance makes the mathematical modelling the most convenient method for the analysis of the interdiffusion process in thin-film systems.    The interdiffusion model during the formation of polycrystalline niobium film – single-crystal silicon systems, developing the Darken’s theory for the limited solubility components was proposed. Grain boundary diffusion of silicon in the intergrain space of a polycrystalline niobium film was proposed. Numerical analysis of the experimental distribution of concentrations within the model established that silicon is the dominant diffusant in the studied system. The temperature dependence of the individual diffusion coefficient of silicon DSi = 3.0 10-12exp(-0.216 eV/(kT)) cm2/s in the temperature range 423–773 K was determined.    The model is applicable to the description of the redistribution of components in the thin niobium film – single-crystal silicon system prior to synthesis conditions providing the chemical interaction of the metal with silicon and the formation of silicides. It illustrates the mechanism of the possible formation of silicide phases not by layer-by-layer growth at the Nb/Si grain boundary, but in its vicinity due to deep mutual diffusion of the components
Evaluation of the inhibitory effect of some derivatives of salts of long-chain carboxylic acids in relation to pitting corrosion of reinforcing steel in concrete
Authors: Kozaderov Oleg A. , Shevtsov Dmitry S. , Potapov Mikhail A. , Zartsyn Iliya D. , Grushevskaya Svetlana N. , Kruzhilin Alexey A. , Ilina Evgeniia A. , Tkachenko Kirill A. , Shikhaliev Khidmet S.
Published: June 2024

Derivatives of salts of long chain carboxylic acids and dimethylaminopropylamine, including those similar in composition to vegetable oils were synthesized. The structure of the molecules of new substances was reliably confirmed using physical methods of IR-Fourier spectroscopy, NMR spectroscopy, and HPLC.     The inhibitory effect of the synthesized substances on 35GS grade reinforcing steel was assessed using voltammetry. Experiments were carried out in an aqueous extract from a mortar, simulating the concrete pore solution, in the presence of chlorides as activators of pitting corrosion, as well as in samples of fine-grained concrete with periodic immersion in a chloride solution. It was found that 3-(dimethylamino)propyl-1-ammonium stearate did not exhibit an inhibitory effect. The introduction of salts of fatty acids of coconut and sunflower oils increased the anti-corrosion properties. The degree of protection was 40-44% in aqueous solutions and 30-32% for concrete samples.     The time before the onset of corrosion in concrete samples was found to increase by 1.75 times compared to the control composition without additives
Natural ferromagnetic resonance in microwires and its applications. Brief review
Authors: Baranov Serghei A.
Published: June 2024

The paper analyzes technological aspects of the Taylor–Ulitovsky method used to produce microwires of various structures.      Natural ferromagnetic resonance (NFMR) in cast glass-coated amorphous magnetic micro- and nanowires was theoretically and experimentally studied. The NFMR phenomenon is due to the large residual stresses appearing in the core of the microwire during the casting process. These stresses, along with magnetostriction, determine magnetoelastic anisotropy. Besides residual stresses, the NFMR frequency is influenced by externally applied stresses on the microwire or the composite containing the so-called stress effect (SE).       The dependence of the NFMR frequency on the deformation of microwires and the external stresses on them is proposed to be used for remote diagnostics in medicine
Pair interaction of intersecting dilatation and disclination defects
Authors: Krasnitckii Stanislav A. , Smirnov Andrei M.
Published: June 2024

An elastic interaction of the intersecting dilatation and disclination defects located in an infinite linear isotropic media is investigated. The eigenstrain approach is employed to obtain the analytical expressions describing the pair interaction between intersecting dilatational lines and intersecting wedge disclinations. It is demonstrated that the interaction energy strongly depends on the intersection angle between the defects. The energy reaches the maximum value if the defect lines are coincided while the energy reaches the minimum value if the defect lines are orthogonal. Besides, it is shown that interaction energy of intersecting wedge disclinations strongly depends on the elastic properties of the media: the less thePoisson ratio, the less the energy. The obtained analytical results seem to be applicable for the theoretical analysis of the residual stress relaxation mechanisms in heterostructures with pentagonal symmetry such as icosahedral particles
Semi-polar GaN(11-22) on nano-structured Si(113): a structure for reducing thermal stresses
Authors: Bessolov Vasily N. , Konenkova Elena V. , Orlova Tatiana A. , Rodin Sergey N.
Published: June 2024

The article reports the growth of semi-polar GaN(11-22) layers using epitaxy from metal organic compounds on a nanostructured NP-Si(113) substrate. It was shown that upon the emergence of an island layer, elastic deformed structures of GaN(11-22)/NP-Si(113) form a nano-meter compliant silicon layer on a substrate while elastic stresses conditioned by the difference of temperature coefficients of GaN and Si in such a structure decrease