Sub-micro Levels Research Articles

Персональний податковий менеджмент: теоретичні аспекти та практична реалізація

Abstract. Introduction. In modern economic literature, tax management is considered at three levels: macro-, microand sub-micro levels. Each of the levels has its subjects, object of management, structure, purpose, methods, tasks and tools. State and corporate tax management are actively researched by domestic scientists, while personal tax management is practically unresearched and needs a more thorough study of theoretical and practical aspects. Purpose. The purpose of this study is to determine the theoretical aspects of personal tax management and to study its practical implementation in our country. Results. The authors gave and analyzed the definitions of domestic scientists and proposed a number of clarifications. In particular, consider personal tax management not from the perspective of an individual citizen, but from the perspective of a household. Also, it is proposed to consider as an object not the management of personal income, but the management of the tax burden, which is calculated as the ratio of the amount of taxes paid to the amount of income. Based on the analysis of the definitions of domestic scientists, an own definition was proposed. In addition, a description of the main elements of the personal tax management system was given. Subjects, object, purpose, methods and tools, stages and blocks of personal tax management are defined. The main reasons for insufficient theoretical justification and practical application of personal tax management in Ukraine are described. Conclusions. As a result of the study, the authors came to the conclusion that personal tax management is an integral part of the financial literacy of the population and consists in the application of tax planning and tax optimization methods. The goal of personal tax management is to reduce the tax burden on the household and maximize their net income. Regarding the prospects for the development of personal tax management in Ukraine, taking into account the extremely unfavorable demographic situation, which has worsened even more due to the war and the crisis of the solidarity pension insurance system, it is extremely necessary at the state level to introduce various mechanisms for increasing the level of financial literacy of the population. The state should encourage households (including through tax instruments) to plan their future incomes, retirement by participating in non-state pension and health insurance, as well as effectively manage savings by using financial market instruments.

Observation and Inference in Chemistry Teaching: a Model-Based Approach to the Integration of the Macro and Submicro Levels

The aim of this article is to propose a didactical approach to establish appropriate relations between different kinds of chemical knowledge and explanations at the macro and the submicro level. Incorrectly moving between these two levels is regarded as the cause of many misconceptions in school chemistry, and several theoretical frameworks have been proposed to remedy those misconceptions. Our literature review of chemistry education shows that a focus of attention for the macro-submicro interplay problem is put in the relations between observations and inferences; we examine such relations with the aid of ideas from the philosophy of science and the specific philosophy of chemistry. We propose a model-based approach that recognises the continuum between empirical and theoretical, descriptive and explanatory in chemical concepts. Finally, we provide an “exemplary activity” on the topic of gases based on this approach, and we evaluate its suitability in terms of some well-established ideas in didactics of science/chemistry.

Endolithic and hypolithic soil-like systems: structure and composition from the macro- to submicro-levels

The paper presents a detailed study on structure and composition of endolithic and hypolithic systems. The following issues are discussed: morphology at macro to submicro levels, biochemical weathering, formation of carbonates and oxalates in situ, migration of Fe compounds, and spatial patterns of endolithic systems. Endolithic and hypolithic systems have major features attributed to soils: (a) rock layer exposed to external abiogenic factors, (b) lithomatrix inhabited by living organisms which are synthesizing and decomposing organic matter, (c) as a result initial parent rock (lithomatrix) is transformed in situ by biogenic and abiogenic factors, the products of transformation are retained and/or removed, the vertical heterogenity is established in a form of microhorizons composing microprofile. Examined profiles of endolithic systems in granitoids of East Antarctica with high quartz content had clear eluvial-illuvial differentiation patterns. Similar patterns have been discovered in different landscapes from the Plateau Ozark in Missouri to the Table Mountain in South Africa.

Virtual Laboratory in the Role of Dynamic Visualisation for Better Understanding of Chemistry in Primary School

Understanding chemistry includes the ability to think on three levels: the macroscopic level, the symbolic level, and the level of particles – sub-microscopic level. Pupils have the most difficulty when trying to understand the sub-microscopic level because it is outside their range of experience. A virtual laboratory enables a simultaneous demonstration of all three levels of a chemical concept along with dynamic visualisation at the submicroscopic level. This study presents the effective usage of a virtual laboratory that can overcome the gap between the previously-mentioned conceptual levels. We carried out a didactic experiment to test the effectiveness of a virtual laboratory that enables dynamic visualisation. The experiment involved seventh-grade pupils (N = 109) from five different primary schools in Slovenia. We asked ourselves the question as to whether the learning outcomes of pupils are better when they use a virtual laboratory rather than in science classes without a virtual laboratory where dynamic visualisation at the submicroscopic and sub-micro levels are only explained by means of static demonstrations. A virtual laboratory has many significant advantages. The results of the didactic experiment showed that, in terms of knowledge acquisition, using a virtual laboratory is better than science classes without visualisation elements.

Malaysian Students' Scientific Argumentation: Do groups perform better than individuals?

The practices of argumentation have recently been upheld as an important need to develop students' understanding of scientific concepts. However, the present education system in Malaysia is still largely examination-based and teacher-oriented. Thus, this study aims to examine the mastery level of scientific argumentation and its scheme among Malaysian secondary-level science students. A total of 120 students were randomly assigned to answer a Scientific Argumentation Test (SAT), either individually or in a group. Based on the answers, two groups of students, one who have answered with valid scientific concepts and another who have answered with invalid concepts, were identified and interviewed. Quantitative analysis was performed on the SAT results to determine students' mastery of scientific argumentation, and their argumentation schemes were assessed using content analysis performed on the interview transcripts. The results showed that students were weak in the construction of scientific arguments with valid concepts. Moreover, most of the constructed arguments consisted of misconceptions. The results also showed that students who were involved in group argumentation tended to have a more complex argumentation scheme, compared to individual students. As a group, students were able to argue with more scientific elements and showed their understanding of macro and submicro concepts. Hence, science teachers need to emphasize on the construction of scientific argumentation in their teaching, especially at the macro, submicro, and symbolic levels of representations, to ensure students' understanding of the concepts. This will therefore enhance their mastery of scientific argumentation and improve their content knowledge.

Mastery of Scientific Argumentation on the Concept of Neutralization in Chemistry: A Malaysian Perspective

Purpose – Argumentative practices are central to science education, and have recently been emphasised to promote students’ reasoning skills and to develop student’s understanding of scientific concepts. This study examines the mastery of scientific argumentation, based on the concept of neutralisation, among secondary level science students, when engaged in individual and group argumentations. Methodology – 356 form four science students were first randomly assigned to an argumentative condition, after their lesson on acids and bases, presented using the developed instructional materials. Each individual or group was then asked to answer an Open-ended Scientific Argumentation Test (OSAT). Discussions during group argumentations were observed and recorded. All the answers provided in the OSAT were then analysed based on their accuracy, the triplet relationship in chemistry and for the presence of argumentation elements. Observations from the group argumentations were transcribed and assessed. Findings – The results show that in both argumentative conditions, most of the arguments constructed tend to consist of the elements of claim and evidence. The results also show that students who work in groups outperform students who work individually. As individuals, most of the arguments presented tend to be simple with reasoning at a macro-level. As groups, the arguments presented are more complex, where justifications are provided at the sub-micro and symbolic levels, and with fewer misconceptions. That is because group argumentation participants have the opportunity to shareideas, detect and correct each other’s mistakes, seek explanations and explain ideas. Significance – The study implies that group argumentation enhances students’ argumentation and reasoning skills and improves their mastery of scientific concepts. In addition, this study also investigates students’ performance from the Malaysian perspective.

Students’ mental models of chemical reactions

Previous research on topics such as atomic structure and chemical bonding indicates that students’ mental models are often inconsistent with the scientific models, which may impede learning of advanced concepts. International research suggests that model- based teaching and learning in science education shows promise in overcoming student misconceptions, but research about modelling for chemical reactions is sparse. In an attempt to redress this schism, this study took the form of an inquiry into a cross-age study of 67 students drawn from secondary schools and universities to investigate their mental models of chemical reactions. This naturalistic qualitative inquiry was based within an interpretive paradigm and constructivist epistemology, in which data were generated from interviews with the participants. The data for this inquiry were derived from semi-structured interviews, incorporating the Interview-About-Instances (I.A.I) technique to probe students’ mental models of chemical reactions for various chemical phenomena. Thematic analysis of the students’ discourse of their mental models revealed different types of mental models, named Model A, B, and C. Each of the mental models was characterised based on features of energy change and the process of chemical reactions at the submicro level. Model A was considered as an initial mental model, which was based on students’ experience with changes of matter in their daily life. This model was also attributed with the notion of agent-driven chemical change as its core characteristic. Basically, Model A explained most of the properties of chemical reactions, including the rate, spontaneity and reversibility of reactions. Although, it can be considered a ‘causality model’, it seemed essential for young students in making sense of the chemical phenomena that surround them. On the other hand, Model B was based on either the attributes related to kinetic theory of particles or attributes related to chemical bonding but this type of mental models seemed to share some characteristics of Model A. However, Model C was likely to incorporate the attributes related to both kinetic theory of particles and chemical bonding as core ideas used in explaining chemical reactions. Students’ preference towards a given model in their mental models is consistent with previous studies. This preference is probably because of their early exposure to the kinetic theory, and it is simplistic but powerful in explaining the nature of chemical phenomena. Nonetheless, the model of chemical bonding was considered an ‘enabling’ model for understanding of the chemical phenomena in terms of rearrangement of atoms and as an affordance to make sense of energy change. Students’ mental models were also compared according to their level of education. Generally, most senior university students were found to hold Model C, while junior university and Form 6 students’ mental models were mostly Model B, and all secondary school students’ mental models were Model A. It seemed then that the more exposed the students are to formal education in chemistry, the more consistent their mental model become with the scientific view. Although students’ mental models were categorised in such a manner, all of the mental models shared common attributes, such as the role of reacting agents in reaction spontaneity, energy as a part of reactions, and irreversibility presumptions. This finding indicates that students’ initial mental models were not ‘erased’ but rather coexisted with the advanced mental models, which were developed through formal education. This relationship is similar to how science operates, where superseded models co-exist with more sophisticated models and are still used for practical purposes although scientists are aware of an old model’s limitations and discrepancies. A general conclusion that can be drawn from this study is that students’ mental models were found to be lacking in attributes that relate to scientific ideas such as particle model, particle collisions, activation energy, and entropy despite these ideas having been introduced in their formal learning. Therefore, it is recommended that students should be engaged in developing mental models that enable them to link between macro and submicro levels through modelling an instruction approach that emphasises the understanding, application and construction of models.

Linguistic Resources Used in Grade 8 Students’ Submicro Level Explanations—Science Items from TIMSS 2007

Explanations involving submicro levels of representation are central to science education, but known to be difficult for students in secondary school. This study examines students' written explanations of physical and chemical phenomena regarding matter and changes in matter, in a large-scale test. This is done in order to understand linguistic challenges in constructing submicro level explanations involving the particle model of matter. Drawing from systemic functional linguistics, the lexicogrammatics used in explanations for realising experiential meaning in student explanations were analysed. We used answers to two partly constructed response items from the Swedish part of Trends in International Mathematics and Science Studies 2007, grade 8, to sort out explanations referring to the particle model of matter. These answers (86 from 954) were analysed regarding choices of vocabulary and grammar to distinguish between macro and submicro level of representation. The results show that students use a wide variety of lexicogrammatical resources to realise what happens on both macro and submicro level of representation, with greater diversity of verbs on the submicro level of explanation. The results suggest an uncertainty about the distinction between macro and submicro level of explanation.

Heterometallic M/Mn ( M=Cu, Co, Zn) acetate complexes as precursors for binary oxides

A facile one-pot procedure, or so-called “direct synthesis,” was used to prepare the novel heterometallic complexes [ M 2Mn(OAc) 6(bpy) 2], where M=Cu ( 1), Co ( 2), Zn ( 3), bpy=2,2′-bipyridyl, with high yields via oxidative dissolution of pure metals in a liquid phase. The complexes were characterized by an elemental analysis, single crystal X-ray diffraction method and FTIR. These complexes are proposed as precursors, whose thermal degradation may lead to the formation of solids possessing nano- to microsize levels of dispersity. The thermal behavior of the complexes obtained was studied by thermal analysis (TG/DTA/DTG) in both air and N 2 and also by TPD mass-spectrometry in vacuo. The FTIR, X-ray powder diffraction (PXRD) and thermoanalytical data were used for the identification of the solid products of thermal degradation. The morphology and microstructure of the solid residues were analyzed, using scanning electron microscopy with energy dispersive X-ray microanalysis (SEM/EDX) at mkm and sub-micro levels.

Determination of Se, Cd, and Hg in an aquatic environment of Bombay by substoichiometric neutron activation analysis

The toxicity of Se, Cd, and Hg as environmental pollutants and the impact of these elements on the aquatic ecosystem is undisputed. The present paper reports an investigation of the concentration of Cd, Se, and Hg in an aquatic environment of a large metropolitan city like Bombay. As the toxicity of these elements manifests itself at micro and submicro levels, the very sensitive technique of neutron activation analysis was employed. A sequential substoichiometric extraction technique for the separation of radiochemically pure203Hg,75Se, and115–115mCd from the neutron irradiated target has also been employed.

Voltammetric Investigations on Ferric-Triethanolamine System for Trace Analysist

Abstract The complexing ability of triethanolamine has been utilised to investigate Fe(III)/Fe(II) redox system at the DME. The DC polarogram of ferric iron in presence of triethanolamine displays a reversible reduction wave which has further been confirmed by cyclic-voltammetric study at a hanging mercury drop electrode. The ferric-triethanolamine complex is estimable in sub-micro levels by employing differential pulse polarography. The technique has yielded the iron contents in drinking, ground and industrial waste waters.