Analysis and Modeling of Curing Polyester Resin in Cylindrical Moulds Heated by Air

Predložen je i izveden matematički model očvršćivanja poliesterskih smola u kalupima valjkastog oblika koji se griju zrakom. Model pretpostavlja konvektivni prijenos topline sa zraka na stijenku kalupa te vođenje topline kroz smolu. Temperatura unutar uzorka mijenja se tijekom očvršćivanja, što je posljedica egzotermnosti reakcije i procesa prijenosa topline. Dodatkom punila u smolu mijenjaju se toplinska svojstva smjese kao i iznos topline koja nastaje reakcijom u istom volumenu uzorka, što vodi do nižih temperaturnih maksimuma u centru simetrije valjkastog kalupa. Model je provjeren mnogobrojnim eksperimentima u kojima je mjerena temperatura uzorka smole unutar kalupa tijekom očvršćivanja. Nezavisnim eksperimentima u kojima je umjesto uzorka smole u kalupu bio glicerol te uz različite brzine strujanja zraka oko kalupa procijenjen je koeficijent prijenosa topline zrak - stijenka kalupa. Dobivene vrijednosti uspoređene su s poznatim korelacijama i dobiveno je dobro slaganje. Predloženim modelom vrlo dobro se može simulirati proces očvršćivanja u valjkastim kalupima te procijeniti utjecaje prijenosa topline i brzine reakcije na maksimalno moguće temperature unutar kalupa.The mathematical model of the cure of unsaturated polyester resin in cylindrical mould heated with warm air was suggested and derived. The model assumes convective heat transfer through air on the wall of the mould and conductive heat transfer through the resin. The temperature within the sample changes during the cure process, which is the result of the reaction being exothermal and the process of heat transfer. The addition of the filler changes the thermal properties of the mixture and reduces the amount of heat generated during the reaction in the sample of the same volume, which leads to lower temperature maximums in the center of the cylindrical mould. The model was tested with multiple experiments in which the temperature of the resin inside the mould during the cure process was measured. The heat transfer coefficients between the air and wall of the mould with different speeds of air flow were estimated using independent experiments where the glycerol was used instead of resin. Estimated values were compared with known correlations and good agreement was obtained. Using the suggested model, the cure process in the cylindrical mould can be simulated accurately and influents of the heat transfer and reaction rate on the temperature maximums can be studied

Evaluation of the length and angulation of the styloid process in the patient with pre-diagnosis of Eagle syndrome

Clinical symptoms caused by the elongated styloid process (SP) or calcified stylohyoid ligament were first described by W. Eagle and they are now known as Eagle syndrome (ES). Normal length of SP was stated by Eagle as 2.5 cm. The objective of this study was to determine and discuss the length of SP and medial angulation degree with computed tomography (CT), which is an affective modality in the identification of ES, and a comparison with related studies. Three-dimensional (3D) images obtained from the axial CT scans of 22 cases (11 males and 11 females) aged between 24 and 80 years, who referred to Cumhuriyet University Hospital, Department of Radiology for multi slice CT with the pre-diagnosis of ES, were used. Lengths of the SP and medial angulations were measured on the obtained images. Inter- and intra-group comparisons were carried out using Wilcoxan and Mann-Whitney U tests. The mean length of the SP was found as 4.1 &#177; 1.1 cm. When inter- and intra-group lengths of the right and left SP were compared, the difference was not significant (p > 0.05). The mean medial angulation of the SP was found as 67.5 &#177; 5.1°. There was a significant difference found between the right side medial angulation and left side medial angulation in all persons (p < 0.05). Lengths of the right and left SP of the patients with pre-diagnosis of ES were close to each other. However, the right-side angulation was observed to be smaller than the left medial angulation in all the patients. Similarly, right side medial angulation of the females was smaller than the left side medial angulation, but this difference was absent in the males. Eagle syndrome should be kept in mind in patients with a sore throat radiating to the ears with swallowing and an observed non-compliance between the complaints such as feeling a foreign body in the throat and facial pain, and physical examination of those who do not have a response to long-term medical therapy should be performed. (Folia Morphol 2011; 70, 4: 295&#8211;299

A gut-to-brain signal of fluid osmolarity controls thirst satiation.

Satiation is the process by which eating and drinking reduce appetite. For thirst, oropharyngeal cues have a critical role in driving satiation by reporting to the brain the volume of fluid that has been ingested1-12. By contrast, the mechanisms that relay the osmolarity of ingested fluids remain poorly understood. Here we show that the water and salt content of the gastrointestinal tract are precisely measured and then rapidly communicated to the brain to control drinking behaviour in mice. We demonstrate that this osmosensory signal is necessary and sufficient for satiation during normal drinking, involves the vagus nerve and is transmitted to key forebrain neurons that control thirst and vasopressin secretion. Using microendoscopic imaging, we show that individual neurons compute homeostatic need by integrating this gastrointestinal osmosensory information with oropharyngeal and blood-borne signals. These findings reveal how the fluid homeostasis system monitors the osmolarity of ingested fluids to dynamically control drinking behaviour

Combustion of Active Carbon as a Model Carbon Material: Comparison of Non-catalytic and Catalytic Oxidation

Kinetics of non-catalytic and Pt-catalysed oxidation of active carbon, selected as a model carbon material was investigated using thermogravimetric analysis (TGA). Investigations were performed in the temperature range from 40 °C to 1000 °C at different heating rates (5–25 °C min–1). The influence of Pt-based catalyst on the combustion kinetics was examined as well. Values of the kinetic parameters, such as activation energy, Ea and Arrhenius pre-exponential factor, A were determined using isoconversional method proposed by Kissinger-Akahira-Sunose. The obtained values were in good agreement with the literature data

Photocatalytic Treatment of Air: How to dealwith the problem of TiO2 deactivation

n this study photocatalytic oxidation of toluene, used as model VOCs in the gas phase on different types of Ti-based catalytic materials was investigated. The objective of this work was to find out additional information regarding activity and stability of catalyst during photocatalytic treatment of the polluted air. Two designs of the photoreactor were used: classical type of an annular reactor and annular reactor with recirculation. All measurements were performed at room temperature, atmospheric pressure and at constant initial toluene concentration, relative humidity and total flow rate of the reaction mixture. Some experiments were carried out with catalysts thermally treated on different temperatures (350–450 °C). It was found out that thermal treatment of deactivated photocatalyst at higher temperature is efficient method of TiO2 reactivation. According to results presented in this paper problem of catalyst deactivation can be partially solved by using annular reactor with recirculation of one part of reaction mixture entering the reactor

REAL ESTATE MARKET IN UKRAINE: TRENDS OF DEVELOPMENT AND CHALLENGES

The development of the real estate market in Ukraine has a positive impact on the economy, contributes to the activation of the banking sector, investment and employment growth, and improvement of living conditions, which, in turn, alleviates social problems. The aim of the article is to study the components of the development of the real estate market in Ukraine. In the course of the work, various general scientific and special research methods were applied, including inductive and deductive methods used to analyze the construction output, GDP, and the consumer price index. With the help of economic analysis and comparison, an analysis of interest rates on deposits in hryvnia and foreign currency for 2005-2020 was carried out. The method of correlation-regression analysis was used to study the relationships between the main influencing factors and the resultant factor (the volume of Ukraine’s real estate market). The graphical method was used to visually represent the results of the study. The abstract-logical method was used for theoretical generalizations and drawing conclusions. The authors analyzed the real estate market in Ukraine and revealed a trend of growth in its capacity in value terms during 2010-2019 and a decrease in 2020 compared to the previous year. To forecast the capacity of this market, it is important to identify the determinants that affect its development. A multiple regression linear econometric model was used to quantitatively assess the impact of different factors on the development of Ukraine’s real estate market. The construction output (residential buildings) in value terms was taken as a resultant factor. Consumer income, housing investment, and divorce rate were taken as factors influencing it. Based on research, it was found that from 2005 to 2020 consumer income increased by 3.6 times, and in 2020 by 6.1%. This is one of the indicators among the respondents, which had a positive trend over the past year. According to the results of research for 2019-2020, investments in housing construction, the number of divorces, and interest rates on mortgage loans in UAH for 2020 decreased by 39.9%, 13.2%, and 0.6 points respectively. Examining these indicators for 2005-2020, we can say that only the number of divorces decreased by 5%. All other indicators increased: interest rates on mortgage loans — by 18.2%, consumer incomes — by 35.5%, and the construction output (residential buildings) — by 4 times. Based on the coefficient of determination, F-test, and von Neumann criterion, it was established that the constructed multiple econometric models are adequate for the statistical data of the population and can be used for further analysis of the economic process. To study the influence of factors on the construction output, partial coefficients of elasticity were analyzed. Based on the performed calculations, it was found that the development of the real estate market in Ukraine is primarily influenced by an increase in consumer income and their investments in residential construction, with a 1% increase leading to a 1.008% and 0.248% increase, respectively, in the construction output (residential buildings) in the real estate market of Ukraine. However, the conditions of the war, the decrease in the income level of the Ukrainian population, decrease in the real estate investments, and the destruction of a significant number of residential and non-residential premises have had a negative impact on the studied market. Its activation is expected in the post-war period — the period of restoration of Ukraine

MIR376A is a regulator of starvation-induced autophagy

Background: Autophagy is a vesicular trafficking process responsible for the degradation of long-lived, misfolded or abnormal proteins, as well as damaged or surplus organelles. Abnormalities of the autophagic activity may result in the accumulation of protein aggregates, organelle dysfunction, and autophagy disorders were associated with various diseases. Hence, mechanisms of autophagy regulation are under exploration. Methods: Over-expression of hsa-miR-376a1 (shortly MIR376A) was performed to evaluate its effects on autophagy. Autophagy-related targets of the miRNA were predicted using Microcosm Targets and MIRanda bioinformatics tools and experimentally validated. Endogenous miRNA was blocked using antagomirs and the effects on target expression and autophagy were analyzed. Luciferase tests were performed to confirm that 3’ UTR sequences in target genes were functional. Differential expression of MIR376A and the related MIR376B was compared using TaqMan quantitative PCR. Results: Here, we demonstrated that, a microRNA (miRNA) from the DlkI/Gtl2 gene cluster, MIR376A, played an important role in autophagy regulation. We showed that, amino acid and serum starvation-induced autophagy was blocked by MIR376A overexpression in MCF-7 and Huh-7 cells. MIR376A shared the same seed sequence and had overlapping targets with MIR376B, and similarly blocked the expression of key autophagy proteins ATG4C and BECN1 (Beclin 1). Indeed, 3’ UTR sequences in the mRNA of these autophagy proteins were responsive to MIR376A in luciferase assays. Antagomir tests showed that, endogenous MIR376A was participating to the control of ATG4C and BECN1 transcript and protein levels. Moreover, blockage of endogenous MIR376A accelerated starvation-induced autophagic activity. Interestingly, MIR376A and MIR376B levels were increased with different kinetics in response to starvation stress and tissue-specific level differences were also observed, pointing out to an overlapping but miRNA-specific biological role. Conclusions: Our findings underline the importance of miRNAs encoded by the DlkI/Gtl2 gene cluster in stress-response control mechanisms, and introduce MIR376A as a new regulator of autophagy

DNA damage-induced dynamic changes in abundance and cytosol-nuclear translocation of proteins involved in translational processes, metabolism, and autophagy

Ionizing radiation (IR) causes DNA double-strand breaks (DSBs) and activates a versatile cellular response regulating DNA repair, cell-cycle progression, transcription, DNA replication and other processes. In recent years proteomics has emerged as a powerful tool deepening our understanding of this multifaceted response. In this study we use SILAC-based proteomics to specifically investigate dynamic changes in cytoplasmic protein abundance after ionizing radiation; we present in-depth bioinformatics analysis and show that levels of proteins involved in autophagy (cathepsins and other lysosomal proteins), proteasomal degradation (Ubiquitin-related proteins), energy metabolism (mitochondrial proteins) and particularly translation (ribosomal proteins and translation factors) are regulated after cellular exposure to ionizing radiation. Downregulation of no less than 68 ribosomal proteins shows rapid changes in the translation pattern after IR. Additionally, we provide evidence of compartmental cytosol-nuclear translocation of numerous DNA damage related proteins using protein correlation profiling. In conclusion, these results highlight unexpected cytoplasmic processes actively orchestrated after genotoxic insults and protein translocation from the cytoplasm to the nucleus as a fundamental regulatory mechanism employed to aid cell survival and preservation of genome integrity.</p

OT Modeling: The Enterprise Beyond IT

Enterprises are composed of an enormous number of elements (e.g., organizational units, human resources, production processes, and IT systems) typically classified in the business or the IT domain. However, some crucial elements do not belong in either group: they are directly responsible for producing and delivering the company’s goods and services and include all the elements that support day to day operations. Collectively, these elements have been called operational technologies (OT) and have been conspicuously excluded from enterprise modeling (EM) approaches which traditionally have focused on the business and IT dimensions. Evidence of this is the absence of OT elements in languages and metamodels for EM. This is in line with the historical division between IT and OT in organizations that has led to information silos, independent teams, and disparate tech- nologies that only recently have started to be reconciled. Considering that OT is critical to most productive organi- zations, and the benefits that EM brings to its understand- ing and improvement, it makes sense to expand EM to include OT. For that purpose, this paper proposes an extension to ArchiMate 3.0 which includes crucial OT elements. On top of that, this paper also proposes an approach to further expand ArchiMate to address specific industries where more specific OT elements are required. This is illustrated in the paper with an extension for the Oil and Gas case that was validated with experts belonging to five companies in the sector