Submicroscopic Level Research Articles

Students’ competence in translating between different types of chemical representations

Meaningful understanding of chemistry, among others, includes the ability of an individual to think simultaneously at macroscopic, submicroscopic and symbolic levels, and this presupposes the competence to translate between different types of chemical representations. In this study, we investigated 11th grade Greek students’ and 3rd year undergraduate chemistry students’ ability to translate chemical representations from one level of chemistry (e.g., submicroscopic) into another (e.g., symbolic) concerning the basic chemical concepts: “chemical element”, “chemical compound”, “aqueous solution” and “solid state of matter”, which have already been taught in earlier grades. We followed a mixed method design in which both quantitative and qualitative research instruments were developed and used. These instruments consisted of multiple choice and open-ended questions, which included real pictures (macroscopic), symbolizations and submicroscopic diagrams. Various representations of the three types were given to the students and they were asked to choose or to construct an equivalent one of a different type. Our results showed that the 11th grade students’ ability to move across the three levels of chemistry is very low, while the 3rd year undergraduate chemistry students’ performance is higher but not satisfactory. In addition, the results obtained from the application of “translation questions” between the three levels of chemistry highlighted many students’ alternative conceptions, some of which still persist among the undergraduate students. The students showed lower performance in translations concerning the concepts “chemical compound” and “aqueous solution” than those concerning the concepts “chemical element” and “solid state of matter”. The students also showed the lowest level of performance in translating the submicroscopic representations into the symbolic ones. Generally, our results indicate that translating between different types of chemical representations is a very challenging task, which depends on students’ conceptual understanding.

Make it real: Simulation of 3D molecules using Augmented Reality in chemical bonding topic

The chemical bonding is one of the crucial topics in chemistry as it becomes a basic concept to comprehend other topics. Unfortunately, it is difficult for students to understand because it is at the submicroscopic level. This study proposes a way to comprehend that topic by developing a simulation of 3D molecules using Augmented Reality (AR). The data was collected by questionnaire. This study was used ADDIE procedure to develop the product. From the results of this study, it can be concluded that the Augmented Reality learning media has a very good quality and is worthy of being used as a supporting media in chemical learning activities in the chemical bond topic.

Verifying the Weight of Different Learning Tasks in Student Assessment by Chemistry Teachers

Abstract Learning tasks are a great motivation tool in chemistry teaching, necessary in the exposure and fixation part of a teaching process, and also often used when diagnosing the depth and type of student knowledge. Our research analysed the relationship between the student assessment in chemistry and their success in solving memory, algorithmic and conceptual tasks at symbolic, submicroscopic and macroscopic levels. The testing focused on chemical equilibrium, because this topic is appropriate to design and test the tasks. The collected data was evaluated by one-factor ANOVA analysis. We expected that, in comparison to average and weak learners, the excellent ones should be significantly more successful in tackling all the types of tasks and at all levels. However, our findings indicate that this assumption is invalid in the case of conceptual tasks, i.e. the understanding the depth of chemical concepts does not always correlate with the student assessment.

Quality of Life Impairment in Adult Patients with ACUTE Lymphoblastic Leukemia with Minimal Residual Disease in France

Introduction: In adult patients with acute lymphoblastic leukemia (ALL), the presence of a minimal residual disease (MRD+), defined as the persistence of tumoral cells at a submicroscopic level, is widely recognized as the most sensitive prognostic factor for relapse and death regardless of treatment choice and risk classification. Although ALL specific treatment guidelines and protocols recommend MRD testing, there is little published literature on how the MRD status would impact on the quality of life (QoL) of adult patients with ALL. This research study aims to describe and assess the impact of MRD status on QoL of different subgroup of adult patients with ALL. Methods: In this French, multi-center, non-interventional, cross-sectional study, a retrospective section consisted of collecting sociodemographic and clinical data extracted from patient medical records of enrolled patients, and a prospective section comprised the following 3 patient reported outcome (PRO) questionnaires that patients completed: the "EuroQol-five-dimensions-3 levels" questionnaire (EQ-5D-3L, a generic PRO from the European Quality-of-life [EuroQol] group), the "Quality of Life Questionnaire - Core 30" (QLQ-C30 , a cancer-specific PRO from the European Organization for Research and Treatment of Cancer [EORTC]), and the "Functional Assessment of Cancer Therapy-Leukemia" questionnaire (FACT-Leu, a leukemia-specific PRO from the Functional Assessment of Chronic Illness Therapy [FACIT]). Adult patients with ALL seen during the inclusion period, regardless of treatment setting and status were enrolled in this Study through hematologists who participated in the study. Results: The study enrolled 221 patients and the analysis was performed on 151 patients who have data on last MRD status. Only 28 patients were MRD+. Median age at the time of inclusion was 57 years (range: 21-83) for MRD+ patients and 53 years (range:19-79) for MRD- patients, 61% and 62% were male, respectively. Median time from diagnosis was 0.5 years and 2.2 years and median age at diagnosis was 53.0 years (range: 5-83) and 48.8 years (range: 5-79), respectively. Less than 40% of the patients received a HSCT prior to inclusion. Most patients (91.9%) who were MRD- at the last testing had an ECOG score 0-1, compared with 71.4% MRD+ patients. More MRD- than MRD+ patients were receiving a frontline therapy (82.1% vs 60.7%) and nearly all (98.4%) MRD- patients had reached a CR at the time of inclusion in this study (vs 50.0% MRD+ patients). Results on all PROs (EQ-5D-3L, QLQ-C30 and FACT-Leu questionnaires) were consistent, showing a lower QoL score in MRD+ patients compared with MRD- patients (Table 1) Using EQ-5D-3L, a higher proportion of patients with MRD+ reported at least one problem that impacted "usual activities", "pain/discomfort" and "selfcare" dimensions; no differences were seen between MRD+ and MRD- patients on "mobility" and "anxiety/depression" dimensions. Using QLQ-C30, symptoms scales and 3 single items ("dyspnea", "insomnia" and "appetite loss") were higher in patients with MRD+ at the last testing than in patients with MRD-, representing a higher level of symptomatology/problems in this group. Using FACT-Leu, all primary QoL domains (except for "social/family well-being" domain) were lower in patients with MRD+ than in patients with MRD-. Conclusions: This study shows that QoL is impaired in patients with MRD+. Disclosures Kutikova: Amgen: Employment. Makhloufi:Amgen (France) SAS: Employment. Chauny:Amgen (France) SAS: Employment. Désaméricq:Amgen (France) SAS: Employment.

LKPD Bentuk Molekul Berbasis Inkuiri Terstruktur Dengan Menggunakan Pemodelan Tiga Dimensi

This study is research and development (RD) and using 4-D models, but disseminate step is not done. Validation of student worksheets has been done by chemistry lecturers and chemistry teachers. The practicality of student worksheets has been done by chemistry teachers and students of 2nd grade of SMAN 1 Pariaman. The result showed that moment kappa average of validity was 0,83 with very high validity category and moment kappa average of practicality were 0,9 by chemistry teachers and 0,86 by students with very high category. Therefore student worksheets of molecular shape based on structured inquiry with emphasis on the submicroscopic level using 3-D models is valid and practice to be used on the chemistry learning.

Using cartoons agents and 3D visualizations based on HTML5 for improving learning in crystal structures in engineers

AbstractThis paper presents an educational digital material on “solid crystal structures,” in which cartoons agents direct undergraduate students on a learning cycle of understanding concepts from the submicroscopic level and correlate with the corresponding macroscopic‐related properties. Specifically, undergraduate students are given the opportunity to study basic crystal structures starting from structural units, composing the unit cells in a three‐dimensional (3D) pattern that are characterized and related with intermolecular forces within them, and finally leading to basic crystalline solids associated with the macroscopic behavior of solid materials expressed by physical and mechanical properties such as hardness, electrical conductivity, etc. The design of the digital material was focused on the cognitive benefits that students gained after viewing 3D visualizations for which students were able to manipulate the rotation or size of them, to enhance their conceptual understanding addressed to chemistry and engineering, accompanied by cartoons agents. Digital material was constructed to be accessible from and compatible with any web browser without any third‐party plugin. A research using a properly designed questionnaire was conducted in the School of Chemical Engineering in Greece where the evaluation indicated that students preferred using this web material due to its simplicity and their active involvement by self‐controlling the pace and the way of learning.

An analysis of students conceptual understanding of submicroscopic level in solubility and solubility product constant (Ksp) using three-tier multiple choice test

This research aims to know the student’s conceptual understanding of the submicroscopic level using a three-tier multiple choice test with the help of multiple representation’s teaching material. This research used mix method with sequential explanatory strategies, and the research subject was students of Islamic senior high school (MA) Riyadlotut Thalabah, Rembang, Central Java, Indonesia which consists of the class of XI IPA 1, XI IPA 2, and XI IPA 3. The data collection technique used three-tier multiple choice test that most questions focus on the submicroscopic level. The result shows that the percentage of students’ Conceptual Understanding of Particulate Level on Solubility and Solubility Product Constant (Ksp) material was 15,14% for Scientific Knowledge(understand)category, misconception type 1 was 7,99%, misconception type 2 was 0,97%, misconception type 3 was 21,55%, lack of knowledge type 1 was 5,06 %, lack of knowledge type 2 was 0,36%, lack of knowledge type 3 was 46,03%, and for lucky guess was 2,86%.

Gisto-ultrastructural changes of temporal muscle in the early stages of streptozotocin diabetes mellitus.

Background. Skeletal muscles are responsible for glucose utilization under the influence of insulin, so they play an important role in glucose metabolism. They are the prime target for insulin action in regulating of blood glucose levels by activating the insulin-sensitive glucose transporter (GLUT-4) on the plasma membrane of the cell. Objective. Therefore, the aim of our work was to establish histological and ultrastructural changes of the temporal muscle oftheratonthe 14th and 28th day of the development of streptozotocin DM (SDM). Methods. 16 adult white male rats (bodyweight 160-200 g) were used for the study. All animals were divided into 2 groups: the first - experimental (10 animals) with SDM (single intraperitoneal injection of streptozotocinat the rate of 6 mg/100 g of bodyweight), the second control (6 animals). Material sampling was carried out on the 14th and 28th days from the beginning of the SDM simulation. Results. On the 14-28th day of the SDM development, there is a significant decrease of the area of muscle fibers in 1.5-1.4 times due to the decrease of the amount of glycogen, which is confirmed by histological and ultrastructural studies. There are initial signs of diabetic microangiopathy, which morphologically manifests itself as a spasm of the afferent vessels, which is confirmed by: a decrease in the area of the lumen of arterioles and an increase on their Vogenvort index; reduced number of capillaries on 0.1 mm2by 1.2 times on the 28th day of the experiment and by an increased area of their wall and Vogenvort index by 1.4 times and 1.3 times, respectively; hemorheological disorders in vessels (erythrocyte clots, adhesion of erythrocytes and platelets, microclasmatosis). Such changes in the vessels of hemomicrocirculatory blood flow lead to muscle hypoxia, that’s why at the submicroscopic level their mitochondria have the most pronounced changes, while the myofibrils retain their ultrastructure. Conclusion. Thus, in early stages of SDM development (14-28 days) on a background of hyperglycemia in temporal muscle we observe: a decrease in the area of muscle fibers due to the reduction in the amount of glycogen in them. In the vessels of the hemomicrocirculatory blood flow, the initial signs of diabetic microangiopathy are manifested, which is characterized by a spasm of afferent vessels, a decrease in the number of capillaries on 0.1 mm2 and an increase in the area of their wall and Vogenvort index, hemorheological disorders in the exchange vessels.

Öğrencilerin Bilimsel Kavram Yanılgılarını Belirlemek İçin Beş Katmanlı Bir Tanı Testi Geliştirilmesi: Isı Transferi Kavramlarına Bir Örnek

The purpose of this article is to propose a new diagnostic test that can be used to diagnose students’ deeper understanding of a concept and what they think about the concept. The instrument is a further development of the existing four-tier test by adding one more tier, drawing sub-microscopic representations. So, this new instrument is called a five-tier test. This instrument can diagnose students’ conceptions in more details and a window to student thinking that can help teachers in diagnosing students’ understanding. Concepts of heat transfer are chosen as the context for developing he instrument since they are considered as essential concepts in school science. The research involved 69 fifth-grade elementary school students from a school in Bandung-Indonesia. This study shows that the five-tier diagnostic test can be used to probe deeper understanding of students. It reveals that most elementary students know the concepts as at the macroscopic level but they had a lack of knowledge at the sub-microscopic level. This study offer new instrument for diagnosing students’ understanding that can be useful for practical purpose as well as researchers.

Assessing Experimental Parameter Space for Achieving Quantitative Electron Tomography for Nanometer-Scale Plastic Deformation

Integrating in situ deformation and electron tomography (ET) techniques allows us to visualize the materials’ response to an applied stress with nanometer spatial resolution. The capability of structural, chemical, and morphological characterization in three-dimension real time and at sub-microscopic levels alleviates several persistent problems of two-dimensional imaging such as the projection effect and postmortem appearance. On the other hand, implementing deformation mechanism introduces additional experimental constraints that could influence the accuracy of the reconstructed volumes in a different way. To materialize quantitative and statistically relevant microstructure interpretation by time-resolved ET, we evaluated several key parameters such as angular tilt range, tilt increment, and reconstruction algorithms to characterize their influences on the accuracy of size and morphology reproducibility.

Multiple Projection Laser Microscopy in the Ulbricht Integrating Sphere (MPLM-UIS) using lens-less microscopes with CCD and CMOS (active-pixel) sensors, including angle sensitive ones.

Microscopy with an integrating sphere (also known as the photometric Ulbricht sphere) is rarely used in histological and cytological practice due to the difficulties in manufacturing the integrating chamber with the technological holes for the sample placing, as well as the high cost of the modern commercially available Ulbricht spheres. The additional difficulties appear at the ultrastructural / submicroscopic level, especially when using near-field optical microscopy (SNOM) techniques determining the size of the integrating sphere. The required correspondence between the radius of the integrating sphere and the size of the specific sample / sample stage results in a physical and technical contradiction, which in principle can be overcome only if a number of conditions are met. The first and obvious one is the equal dimensions of the transmission window of the sample stage and the sample itself. The final condition is obtaining a wide-field image at the stationary position of the stage, since its displacement inside the integrating sphere will lead to the changes in the light-shadow (schlieren) structure of the registrogram. The same is true for the movement of the coordinate stage or a slide / sample itself, but for the sample in vivo / in situ perturbations of the optical field of the isotropic-integrating sphere can be used as an analytical signal. In a general case, when all the above planes and sections are located at the stationary position at the center of the Ulbricht sphere, the only possible solution is to use CCD / CMOS sensors with a simple printed circuit board, which act as an analytical chip with a function of a lensless projection microscope instead of the reduced conventional optical microscope.

Construção de Modelos 3D impressos como estratégia para a aprendizagem do conceito de interação enzima-substrato

No ensino de Bioquímica a compreensão da natureza tridimensional tem sido favorecida pelo uso de ferramentas de visualização e representação de conceitos e processos. Entre estas ferramentas encontram-se os modelos concretos, que permitem, além da aprendizagem conceitual, o desenvolvimento de habilidades visuais fundamentais para a transição entre o nível macroscópico e submicroscópico. Este trabalho tem como objetivo apresentar as contribuições da construção e do uso de modelos 3D impressos para a aprendizagem do conceito de interação enzima-substrato, pelos licenciandos em Química matriculados na disciplina obrigatória de Bioquímica. Desenhos foram utilizados para investigar a ideia de “interação enzima-substrato”, no início e no final de uma sequência de atividades de modelagem 3D realizadas pelos licenciandos. A análise do uso dos modelos 3D impressos no processo de ensino e aprendizagem do conceito de interação enzima-substrato foi realizada comparando-se os elementos codificados nos desenhos antes e após a participação nas atividades de modelagem 3D. Os resultados apontam que a participação dos estudantes na construção dos modelos 3D impressos contribuiu para a percepção de aspectos químicos da interação enzima-substrato, no sentido de compreender a complexidade do fenômeno em questão.

Dimension of Chemical Literacy and its Influence in Chemistry Learning

Chemical literacy is an ability that is important for students to have in the current educational era. This study aims to measure the ability of chemical literacy of high school students by using questionnaires and questions through investigation. This research was a qualitative descriptive study with samples engaging 100 students from Surakarta and Boyolali High Schools. This study investigated the achievement of the ability of chemical literacy of high school students in class XI and XII for the material of electrolyte and non-electrolyte solutions. The measured chemical literacy abilities included: a) nominal literacy (recognizing the concept of chemistry); b) functional literacy (defining key concepts); c) conceptual literacy (using chemical understanding to explain the phenomena of everyday life); and d) multidimensional literacy (using the understanding of chemistry to analyze information provided in short articles or other reading sources). The test instruments used were questionnaires, choice questions, and open-ended questions supplemented with interviews to obtain the data on the concept of students’ chemical literacy. The results of the study found that students were able to explain the concept of chemistry at the macroscopic level, but in the submicroscopic level the students’ ability was still low. This showed that students’ chemical literacy skills at the conceptual level and multi-dimensional literacy were still less. The findings of this study can help design learning strategies and teacher readiness in supporting students to develop students’ chemical literacy skills.

Kimya Öğretmen Adaylarının Çözünürlük Konusuna İlişkin Submikroskobik Seviyedeki Anlama Düzeylerinin Çizimlerle Belirlenmesi

Bu araştırmanın amacı kimya öğretmen adaylarının çözünürlük konusuna ilişkin submikroskobik seviyedeki anlama düzeylerini tanecik boyutunda çizimler ile belirlemektir. Araştırmada örneklem grubu olarak Van Yüzüncü Yıl Üniversitesi ve Gazi Üniversitesi’nin Kimya Öğretmenliği programının 3. ve 4. sınıfında öğrenim gören toplam 36 kimya öğretmen adayı seçilmiştir. Bu çalışmada, kimya öğretmen adaylarının çözünürlük konusuna dair anlama düzeylerini derinlemesine incelemek için nitel araştırma yöntemine ait durum çalışması araştırmanın deseni olarak belirlenmiştir. Araştırmada veriler çözünürlük ve çözünürlüğü etkileyen faktörler konusunda tanecik boyutunda çizim ile açıklama gerektiren sorular içeren bir test yardımıyla toplanmıştır. Testten elde edilen veriler içerik analizi yöntemi ile analiz edilerek, öğretmen adaylarının cevapları ve tanecik boyutundaki çizimleri doğru, kısmen doğru ve yanlış cevap/çizim olarak değerlendirilmiştir. Elde edilen bulgular öğretmen adaylarının submikroskobik düzeyde anlama seviyelerinin düşük olduğu sonucuna ulaşılmıştır. Öğretmen adaylarının çözünürlük ve çözünürlüğü etkileyen faktörlere dair submikroskobik seviyede molekül, iyon veya tanecikleri göstermekte zorlandıkları tespit edilmiştir.

MEDIA LITERACY AND SCIENTIFIC EDUCATION: THE STUDENTS’ PROTAGONISM

Currently, a discursive resource widely used is images, whose use can facilitate the explanation of concepts, constituting essential support for the communication of scientific ideas. This article reports the results of a study on the perception of 107 students of two High Schools located in São Paulo (Brazil) concerning representations of the physical state change processes at a sub-microscopic domain. After the development of a teaching-learning sequence (TLS) about the properties of matter, discussions were conducted both in small groups and with the whole class. At this point, students were asked to draw up images that represent their understanding of the phenomena of physical changes at the sub-microscopic level. In the second phase of the TLS, after some discussion about the drawings previously produced, each group of students was asked to create an audiovisual object (AO) concerning the phenomena. It was possible to perceive both the evolution of their expressed mental representations that present scientific features more consistently and the students’ more coherent and secure speech. These results suggest that the multimodal approach promotes opportunities both for the building of models by the students, and their expression is essential to chemistry language learning. Keywords: multimodal approach, media literacy, sub-microscopic domain, science education

3D magnetostrictive Preisach model for the analysis of magneto-electric composites

In the present contribution, we compare numerical simulations of magneto-electric composites with experimental measurements. The coupling between electric polarization and magnetization of such materials can improve the operation of sensors and actuators and can enable new technical devices. These composites consist of a ferroelectric and a magnetostrictive phase and generate the ME coupling as a strain-induced product property. However, the responses of the individual phases are highly nonlinear. It is important to predict the behaviors of both phases in an appropriate manner to ensure a realistic prediction of the magneto-electric coefficient. Therefore, we simulate the nonlinear ferroelectric hysteresis curves based on the ferroelectric and ferroelastic switching behavior of the spontaneous polarization directions on the submicroscopic level. Therefore, a switching criterion considering the change in the free energy is evaluated. For the simulation of the magnetostrictive behavior, we derive in this contribution a three-dimensional Preisach model. For this, the classical scalar Preisach model acts on a rotational time-dependent magnetization vector. After a homogenization approach within the finite-element ( $$\hbox {FE}^2$$ )-method, the effective macroscopic hysteresis curves are obtained. Furthermore, the magneto-electric coefficient is obtained from the homogenization and compared with experimental measurements in terms of magnitude and nonlinear behavior.

Achievement profile of high school students on chemical dynamics material at three levels of representation

This study aims to explore information about the achievement profile of high school students on chemical dynamics material at three levels representation. This research uses non experimental design in the form of survey. Sample of the survey was 219 students of 11th grade high school students in Ketapang, West Borneo. Cluster random sampling was used as a sampling method. The data collection of survey use a multiple choice tests that contains chemical dynamics material that includes chemical kinetic concepts and chemical equilibrium concepts. Each item of the tests contains three levels representation such as macroscopic levels, symbolic levels, and submicroscopic levels. Based on the findings, it shows that high school students in Ketapang have high mean score of symbolic representation by 55,1%, and sequentially 49,8% in macroscopic level, and 40,8% in submicroscopic level. The results based One Way ANOVA tests conclude that the mean score of each representation level was significantly different.

Teachers, pre-service teachers, and students understanding about the heat conduction

The purpose of this study is to analyze teachers, pre-service teachers, and students conceptual understandings related to heat conduction in macroscopic and sub-microscopic (verbal and visual). This description research involves 15 teachers, 33 pre-service teachers, and 39 students. Data were collected by using a conceptual understanding diagnostic test. The result shows that almost the participants know about the macroscopic level. However, most of them have a few understanding at the sub-microscopic level in verbally and no one of them can draw or represent the scientific conception about the sub-microscopic level. This study suggested that the sub-microscopic level of the science concepts must be learned and taught to students to make science more easy to understand and explained.

Exploring prospective chemistry teachers’ perceptions of precipitation, conception of precipitation reactions and visualization of the sub-microscopic level of precipitation reactions

In this study, how prospective chemistry teachers (PCTs) perceive precipitation and conceptualize precipitation reactions at the symbolic level was explored. Further, it was of interest to identify PCTs’ visualization of the sub-microscopic level of precipitation reactions. The sample was drawn from the Chemistry Education Department at the Education Faculty of a Turkish Public University. A total of 46 PCTs (10 in the 4th semester, 15 in the 6th semester, and 21 in the 8th semester) participated in the study. The data were collected using an instrument with three open-ended questions developed by the authors and with interviews. It was revealed that the PCTs thought about precipitation in qualitatively different ways depending on their practices of phenomena. The PCTs’ perceptions of precipitation were grouped into three issues coded as (1) reacting two salt solutions, (2) undissolved solid and (3) residue. It was found that half of the PCTs (24 of the 46 PCTs) did not use state symbols when writing the precipitation equations and more than half of them included the molecular dissolution features in their drawings. It was suggested that instruction should be to address incorporating a relation between the sub-microscopic, symbolic and macroscopic levels by using the animations.

The impact of students’ educational background, interest in learning, formal reasoning and visualisation abilities on gas context-based exercises achievements with submicro-animations

The purpose of this paper is to explore and explain students’ achievements in solving context-based gas exercises comprising the macroscopic and submicroscopic levels of chemical concepts. The influence of specific variables, such as interest in learning, formal-reasoning abilities, and visualisation abilities, is a significant factor that should be considered when explaining students’ achievements with context-based exercises. Seventy-nine students of three age groups (12, 16, and 23) participated in the study. Questionnaires, tests, and a semi-structured interview including computer-displayed context-based exercises were used to collect data. In addition, an eye-tracker was used to determine the exact location of the participants’ points of gaze. The results show that students on average answered correctly from 40 to 79% of all questions in the context-based exercises. The context-based exercise related to air compression is indicated as being difficult for students. In students’ explanations of different levels of chemical concepts, representation difficulties are detected in all three age groups of students. Students’ achievements in solving context-based gas exercises do not depend on interest in learning chemistry and visualisation abilities. However, statistically significant differences exist in total fixation duration on the correct submicrorepresentation animation between students with different formal-reasoning abilities. The results serve as a starting point for the planning of different context-based exercises and problems comprising the chemistry triplet with 3D dynamic submicrorepresentations.