CRISTAL-ITE: a single-crystal X-ray diffractometer scale model for scientific dissemination

This article presents the design and manufacture of an automated scale model of a four-circle single-crystal X-ray diffractometer that can be used for scientific dissemination. The purpose of this device is to reach out to the wider public and students to introduce them in an entertaining way to one of the laboratory apparatuses to which they do not usually have access, to talk to them about crystallography in the broadest sense, to develop concepts in various fields of science and technology, and to initiate interest and discussions. The main technical aspects of the project are described, with the expectation that such an approach could be useful to anyone involved in scientific dissemination and could be developed for other laboratory equipment and other disciplines. This kind of device can also be the subject of scientific and technological projects in close collaboration with educational institutions.

HAT-field: a very cheap, robust and quantitative point-of-care serological test for Covid-19.

We have recently described a very simple and cheap serological test called HAT to detect antibodies directed against the RBD of the SARS-Cov-2 virus. HAT is based on hemagglutination, triggered by a single reagent (IH4-RBD) comprised of the viral RBD domain fused to a nanobody specific for glycophorin, which is expressed at very high levels at the surface of human red blood cells (RBCs). One of the main initial goals of this study was to devise a test protocol that would be sensitive and reliable, yet require no specialized laboratory equipment such as adjustable pipets, so that it could be performed in the most remote corners of the world by people with minimal levels of training. Because antibody levels against the viral RBD have been found to correlate closely with sero-neutralisation titers, and thus with protection against reinfection, it has become obvious during the course of this study that making this test reliably quantitative would be a further significant advantage. We have found that, in PBN, a buffer which contains BSA and sodium azide, IH4-RBD is stable for over 6 months at room temperature, and that PBN also improves HAT performance compared to using straight PBS. We also show that performing HAT at either 4°C, room temperature or 37°C has minimal influence on the results, and that quantitative evaluation of the levels of antibodies directed against the SARS-CoV-2 RBD can be achieved in a single step using titration of the IH4-RBD reagent. The HAT-field protocol described here requires only very simple disposable equipment and a few microliters of whole blood, such as can be obtained by finger prick. Because it is based on a single soluble reagent, the test can be adapted very simply and rapidly to detect antibodies against variants of the SARS-CoV-2, or conceivably against different pathogens. HAT-field appears well suited to provide quantitative assessments of the serological protection of populations as well as individuals, and given its very low cost, the stability of the IH4-RBD reagent in the adapted buffer, and the simplicity of the procedure, could be deployed pretty much anywhere, including in the poorest countries and the most remote corners of the globe.

Short Communication: Mechanism and Prevention of Irreversible Trapping of Atmospheric He During Mineral Crushing

A pervasive challenge in noble gas geochemistry is to ensure that analytical techniques do not modify the composition of the noble gases in the samples. Noble gases are present in the atmosphere and are used in a number of manufacturing procedures and by laboratory equipment. Of particular concern is the introduction of atmospheric or laboratory noble gases to samples during preparation before samples are placed in a vacuum chamber for analysis. Recent work has shown the potential for contamination of crushed samples with air-derived He that is not released by placing the samples under vacuum at low temperature. Using pure He gas as a tracer, we show that the act of crushing samples to a fine powder itself can introduce He contamination, but that this is easily avoided by crushing under liquid or in an inert atmosphere. Because the He is trapped during crushing, the same concern does not extend to samples that are naturally fine-grained when collected. The degree of He contamination even from crushing samples to sizes smaller than typically used for geochronology is insignificant for samples at least 1 Ma and with more than 1 ppm U when the guidelines outlined here are followed.

Semi-Manual Processing Of Blood Clamps Waste into Chitosan Powder

Blood clams (Anadara granosa) are endemic clams found in Southeast Asia and East Asia. Blood clams are widely consumed by the public as seafood dishes in coastal food stalls. The great potential of blood clams will increase the waste of clam shells produced. The accumulation of shellfish waste will cause pollution and reduce environmental aesthetics. The chitin content in blood clam shells can be used as chitosan. Chitosan is a polymer of -(1-4) glucosamine which is formed when the acetyl group in chitin is substituted by hydrogen to become an amine group. Chitosan has antibacterial and antifungal properties. Isolation of chitosan was carried out through the stages of demineralization, deproteination, and deacetylation. The limited use of laboratories during the pandemic is a major obstacle in the isolation process of chitosan. This study aims to process blood clam shell waste into chitosan in a simple way on a home scale. Processing includes deproteination, demineralization, and deacetylation were done using tools and materials available at home. Laboratory equipment such as beakers could be replaced with pots, the reflux process was replaced by using a cloth to filter, and measuring cups were replaced with glasses. The research used 1500 grams of blood clam shell powder and produced 1050 grams of white chitosan with a slightly hard texture

АНАЛІЗ ЕНЕРГЕТИЧНИХ ХАРАКТЕРИСТИК БУДІВЛІ НАВЧАЛЬНОГО КОРПУСУ СКЛАДНОЇ КОНФІГУРАЦІЇ ІЗ РОЗРОБКОЮ ПРОПОЗИЦІЙ ПО ПІДВИЩЕННЮ ЕНЕРГОЕФЕКТИВНОСТІ

There are many approaches to assessing the energy performance of buildings. In Ukraine, previously, when developing the energy passport of buildings, a method based on stationary calculations using degree-days of the heating period was used. Then, for the tasks of energy certification of buildings, a national calculation method based on the monthly quasi-stationary method was introduced. The simplified hourly method of calculation allows to consider thermal inertia of protections. In recent years, the methods of dynamic energy modeling using software packages have become increasingly relevant, because it allows at the preliminary design stage to estimate energy costs for different building needs before and after the implementation of energy efficiency projects and provides the ability to create 3D models based on geometric and thermal parameters, tasks of different configurations and types of engineering systems of the building. To build an energy model, a training building was chosen to determine energy consumption indicators and identify measures that have the greatest impact on the energy performance of the building.Purpose. Evaluation of energy characteristics of the educational building of a higher education institution with modeling of energy consumption in specialized software, technical and economic evaluation of opportunities to increase energy efficiency.Research methods. Energy inspection of the object of research and technical and economic analysis with the use of engineering methods of calculation, experimental measurements of the parameters of the microclimate of the building with the use of laboratory equipment were performed. Simulations are used in specialized software products RETScreen, EnergyPlus, DesignBuilder.Result. With the help of the developed models the structure of energy consumption of the educational building is obtained and the assessment of energy saving potential is carried out; in case of implementation of the proposed measures it is expected to reduce the consumption of energy resources and monetary costs for their payment, as well as improve the quality of educational services. The research was conducted as part of a master's thesis.Scientific novelty. The technical potential of this software for modeling the energy performance of a building of complex configuration on the example of the educational building of the educational institution, analyzed the methods of processing initial data for programs, comparative analysis of calculation results for the actual condition of the building, baseline and after implementing energy saving measures.Practical significance. As a result of the research, the potential of using different software packages to perform applied research of the master's dissertation was determined and a project of complex thermal modernization of the building of the educational building was developed.

The <i>μ</i>Dose system: determination of environmental dose rates by combined alpha and beta counting – performance tests and practical experiences

The μDose system is a recently developed analytical instrument applying a combined α- and β-sensitive scintillation technique for determining the radioactivity arising from the decay chains of 235U, 238U and 232Th as well as from the decay of 40K. The device was designed to meet the particular requirements of trapped charge dating methods and allows the assessment of environmental (i.e. low) levels of natural radionuclides. The μDose system was developed as a piece of low-cost laboratory equipment, but a systematic test of its performance is still pending. For the first time, we present results from a comprehensive performance test based on an inter-laboratory comparison. We compare the results obtained with μDose measurements with those from thick source alpha counting (TSAC), inductively coupled plasma optical emission spectrometry (ICP-OES) and low-level high-resolution gamma spectrometry (HRGS) applied in five participating laboratories. In addition, the reproducibility and accuracy of μDose measurements were tested on certified reference materials distributed by the International Atomic Energy Agency (IAEA; RGU-1, RGTh-1 and RGK-1) and on two loess standards (Nussy and Volkegem) frequently used in trapped charge dating studies. We compare μDose-based results for a total of 47 sediment samples with results previously obtained for these materials by well-established methods of dose rate determination. The investigated natural samples cover a great variety of environments, including fluvial, aeolian, littoral, colluvial and (geo-)archaeological sites originating from high and low mountain regions as well as from lowlands in tropical areas, drylands and mid-latitude zones of Europe, Africa, Australia, Central Asia and the Americas. Our results suggest the μDose system's capability of assessing low-level radionuclide contents with very good accuracy and precision comparable to well-established dosimetry methods. Based on the results of our comparative study and with respect to the practical experiences gained so far, the μDose system appears to be a promising tool for trapped charge dating studies.

Automated Detection Model in Classification of B-Lymphoblast Cells from Normal B-Lymphoid Precursors in Blood Smear Microscopic Images Based on the Majority Voting Technique

Introduction. Acute lymphoblastic leukemia (ALL) is the most common type of leukemia, a deadly white blood cell disease that impacts the human bone marrow. ALL detection in its early stages has always been riddled with complexity and difficulty. Peripheral blood smear (PBS) examination, a common method applied at the outset of ALL diagnosis, is a time-consuming and tedious process that largely depends on the specialist’s experience. Materials and Methods. Herein, a fast, efficient, and comprehensive model based on deep learning (DL) was proposed by implementing eight well-known convolutional neural network (CNN) models for feature extraction on all images and classification of B-ALL lymphoblast and normal cells. After evaluating their performance, four best-performing CNN models were selected to compose an ensemble classifier by combining each classifier’s pretrained model capabilities. Results. Due to the close similarity of the nuclei of cancerous and normal cells, CNN models alone had low sensitivity and poor performance in diagnosing these two classes. The proposed model based on the majority voting technique was adopted to combine the CNN models. The resulting model achieved a sensitivity of 99.4, specificity of 96.7, AUC of 98.3, and accuracy of 98.5. Conclusion. In classifying cancerous blood cells from normal cells, the proposed method can achieve high accuracy without the operator’s intervention in cell feature determination. It can thus be recommended as an extraordinary tool for the analysis of blood samples in digital laboratory equipment to assist laboratory specialists.

Virtual Reality Training Application for the Condition-Based Maintenance of Induction Motors

The incorporation of new technologies as training methods, such as virtual reality (VR), facilitates instruction when compared to traditional approaches, which have shown strong limitations in their ability to engage young students who have grown up in the smartphone culture of continuous entertainment. Moreover, not all educational centers or organizations are able to incorporate specialized labs or equipment for training and instruction. Using VR applications, it is possible to reproduce training programs with a high rate of similarity to real programs, filling the gap in traditional training. In addition, it reduces unnecessary investment and prevents economic losses, avoiding unnecessary damage to laboratory equipment. The contribution of this work focuses on the development of a VR-based teaching and training application for the condition-based maintenance of induction motors. The novelty of this research relies mainly on the use of natural interactions with the VR environment and the design’s optimization of the VR application in terms of the proposed teaching topics. The application is comprised of two training modules. The first module is focused on the main components of induction motors, the assembly of workbenches and familiarization with induction motor components. The second module employs motor current signature analysis (MCSA) to detect induction motor failures, such as broken rotor bars, misalignments, unbalances, and gradual wear on gear case teeth. Finally, the usability of this VR tool has been validated with both graduate and undergraduate students, assuring the suitability of this tool for: (1) learning basic knowledge and (2) training in practical skills related to the condition-based maintenance of induction motors.

MATEMATIKA DALAM FILSAFAT PENDIDIKAN

<p class="AfiliasiCxSpFirst" align="left"><strong>Abstrak:</strong><strong></strong></p><p class="AfiliasiCxSpMiddle">Tujuan artikel ini adalah memberikan informasi mengenai pengertian filsafat matematika, pengertian filsafat pendidikan dan hubungan antara matematika dengan filsafat pendidikan. Jenis penelitian yang digunakan adalah penelitian deskriptif dan studi literatur (<em>library research</em>). Temuan dalam artikel ini adalah hubungan antara matematika dan filsafat pendidikan yang saling bersinergi satu sama lain. Kesamaan antara matematika dan filsafat adalah memiliki objek kajian yang sama yaitu begerak pada tingkat generalitas dan abstraksi yang tinggi, mempergunakan akal/ rasional dan tidak melakukan eksperimen, serta tidak memerlukan peralatan laboratorium. Namun, matematika dan filsafat juga memiliki perbedaan yaitu jenis metode dalam menelaah suatu kebenaran. Matematika menggunakan metode deduksi dimana kebenaran dari hasil penelaahannya harus dapat ditunjukan dengan serangkaian langkah pembuktian. Sedangkan filsafat menggunakan macam–macam metode rasional dimana proses pembuktian itu tidak harus terjadi tetapi harus berlangsung dengan alasan-alasan yang diperoleh dari penalaran serta dapat bersifat fleksibel.</p><p class="AfiliasiCxSpMiddle"> </p><p class="AfiliasiCxSpLast" align="left"><strong>Kata Kunci</strong>:</p><p>Matematika, Filsafat, Pendidikan</p><p> </p><p class="Afiliasi"><strong><em>Abstract:</em></strong></p><pre><em>This study aims to inform the concept of philosophy in mathematics, the concept of philosophy in education, and the relationship between mathematics and the philosophy of education. This study follows a descriptive approach with a literature study (library research). The findings indicate the relationship between mathematics and educational philosophy that synergize with each other. The similarity between mathematics and philosophy is that they have the same object of study, namely dealing with a high level of generality and abstraction, using reason/rationality, not conducting experiments, not requiring laboratory equipment. However, mathematics and philosophy are also different in terms of the method in examining a truth. Mathematics uses deduction where the truth of the results of the study must be presented by steps of proving evidence. Meanwhile, philosophy uses various traditional methods where the process of proving evidence does not need to be presented, but it must take place with reasons derived from reasoning and can be flexible.</em><em></em></pre><pre><em> </em></pre><p class="Afiliasi" align="left"><strong><em>Keywords</em></strong><em>:</em></p><em>Mathematics, Philosophy, Education</em>

Fractionation of Soil Organic Matter into Labile and Stable Fractions

The present study aims to test and evaluate the efficiency of a new modified method of organic matter evaluation. It allows the assessment of the quality and quantity of the primary soil organic matter and the stable organic fractions separately. The new method was tested in six soil samples of different localities in the Czech Republic. This method is based on observing reaction kinetics during the oxidation of soil organic matter and measuring the cation-exchange capacity of stable organic fractions. The results were compared with classical methods, which rely on the isolation of humic substances, determination of the content of humic acids and fulvic acids and their ratio CHA:CFA, quotient E4/6, and fractionation of soil organic matter according to resistance to oxidation. It turned out that the results of the new modified method are more sensitive in comparison with the results obtained by classical procedures. The linear regression demonstrated the dependence between the amounts of soil organic matter determined by the classical method compared with the modified method. Moreover, the new modified method was found to be faster and not demanding on laboratory equipment. The new method has been improved to be easily repeatable, and some shortcomings of the previous method were eliminated. Based on our results and other recent studies, the modified method may be recommended for the practical evaluation of soil organic matter conditions.