Chemical Balance Research Articles

Data-driven prediction of the output composition of an atmospheric pressure plasma jet

Cold atmospheric plasma (CAP) in open air hosts numerous chemical species engaged in thousands of chemical reactions. Comprehensive diagnosis of its chemical composition is important across various fields from medicine, where reactive oxygen and nitrogen play key roles, to surface modification. In applications, a centimeter-scale helium–air jet operates for minutes, featuring micrometer-sized streamers and an atmospheric pressure-induced collision frequency in the hundreds of GHz range. To address this intricate multi-scale issue, we introduce a machine learning approach: using a physics-informed neural network (PINN) to tackle the multi-scale complexities inherent in predicting the complete list of species concentrations, gas temperature, and electron temperature of a CAP jet supplied with a mixture of helium and air. Experimental measurements of O3, N2O, and NO2 concentrations downstream of the plasma jet, combined with fundamental physics laws, the conservation of mass and charge, constrain the PINN, enabling it to predict the concentrations of all species that are not available from the experiment, along with gas and electron temperatures. The results, therefore, obey all the physical laws we provided and can have a chemical balance with the measured concentrations. This methodology holds promise for describing and potentially regulating complex systems with limited experimental datasets.

Hydrochemical Characteristics and Controlling Factors in Wudu River Basin of Guizhou Province

TheWudu River is a typical mining-type watershed in the karst mountainous area of western Guizhou Province. Based on the collection of the main stream, tributaries, spring water, and mine water samples in Wudu River Basin, the hydrochemical characteristics and control factors of Wudu River Basin were studied using Gibbs diagram, Piper diagram, and mathematical statistics analysis, and the solute contribution rate of different sources was calculated. The results revealed that the pH value of the water in the Wudu River Basin ranged from 7.87 to 8.52, with an average of 8.14. The TDS values ranged from 135 to 243 mg·L-1, with an average of 191.7 mg·L-1. The major cations in natural river and spring water were Ca2+ and Mg2+, the major anion was HCO3-, and the hydrochemical type was HCO3-Ca. However, owing to the influence of mining activities, the major cations in some tributaries were Ca2+ and Na+, and the hydrochemical types transitioned to HCO3·SO4-Ca and HCO3·SO4-Ca·Na. The ion components of river water in Wudu River Basin were affected by mine water discharge and cation exchange, carbonate rock weathering, silicate rock weathering, and agricultural fertilization. The high concentration of SO42- and Na+in mine water was the primary source of SO42- and Na+in the tributaries of the Wudu River. The method for calculating chemical material balance showed that the contribution rate of carbonate rock weathering ranged from 44.12% to 86.92%, with an average of 74.32%. The contribution rate of mining activities ranged from 3.28% to 37.07%, with an average of 11.61%. Carbonate rock weathering was the main controlling factor of hydrochemical components in the Wudu River Basin; meanwhile, mining activities also had a certain impact on river water chemistry but they showed spatial heterogeneity. The average contribution rates of atmospheric precipitation, silicate rock weathering, agricultural activities, and domestic sewage were 3.75%, 4.67%, 2.85%, and 2.81%, respectively, which had a limited impact on the hydrochemical components of the basin.

MODELING OF TEMPERATURE FIELDS AND GAS-DYNAMIC FLOWS IN THE ZONE OF PLACEMENT OF LITHIUM CERAMICS SAMPLES DURING TGA STUDIES

Modeling of thermogravimetric experiments is an essential tool for understanding the physical and chemical processes that occur during research. This approach helps improve data quality and gain a better understanding of what is going on during thermogravimetric analysis.This paper describes the procedure for modeling a TGA experiment on a Mettler Toledo TGA/DSC 3+ gravimeter, which, together with a mass spectrometer, a humidity generator, and an analytical balance, is part of the TiGRа analytical complex (NNC RK, Kurchatov, Kazakhstan). A description is given of the problem of modeling heat transfer processes in a gravimeter, the process of mass transfer of the reaction gas and reaction products in the gravimeter chamber, as well as the processes of chemical interaction of lithium ceramics with the reaction gas during TGA experiments. Helium with an admixture of oxygen and water vapor was considered as the purge gas.Calculations carried out using the developed model show that at a purge gas supply rate of 100 ml/s, the temperature gradient across the samples will be 2–2.5 ℃, and the gas velocity in the pebble bed will not exceed 0.5 mm/s. It has been established that the concentrations of CO2 carried away by the helium flow above the backfill and in the exit zone (in the sampling zone of the mass analyzer) at different temperatures can differ up to 22 times. Thus, using the developed model, it is possible to calculate the concentrations of CO2, CO, and H2 at any point of the thermogravimeter furnace directly above the test sample, inside and/or outside the pebble bed, in the area of the reaction mixture inlet and in the sampling area of the mass analyzer, etc. Also, if necessary, it is possible to determine the coefficients for recalculating concentrations in different sections of the pebble bed relative to the measured value. Using this model, it is possible to determine the parameters of chemical reactions – the initial concentration of carbon in the pebble bed, the activation energy of the reactions, and the concentration of O2 and H2O impurities in the purge helium, achieving the coincidence of the calculated and recorded curves using a mass analyzer. The developed model has a practical potential for further expansion of its analytical capabilities by refining the list of chemical reactions.

Evaluation of the addition of adrenaline in a bilateral maxillary nerve block to reduce hemorrhage in dogs undergoing sharp staphylectomy for brachycephalic obstructive airway syndrome. A prospective, randomized study.

To assess the use of adrenaline (0.00198%) in a bilateral maxillary nerve block to reduce intraoperative hemorrhage in dogs undergoing staphylectomy for the treatment of brachycephalic obstructive airway syndrome (BOAS). Prospective, randomized, double-blinded controlled study. A total of 32 client owned, clinically affected dogs undergoing a cut and sew sharp staphylectomy for treatment of BOAS. A total of 16 dogs randomly assigned to adrenaline (A) group and 16 to no-adrenaline (NA) group. A bilateral maxillary nerve block was performed in all dogs prior to staphylectomy using lidocaine alone (group NA) or a combination of lidocaine and adrenaline (group A). Total hemorrhage was measured by weighing cotton-tipped applicators and swabs used on precision scales. In addition, a semi-quantitative hemorrhage score (1-5) was determined. Dogs were monitored for intraoperative hemodynamic stability during the procedure. Total hemorrhage was significantly (p = .013) lower in group A compared with group NA. The median semi-quantitative hemorrhage score was significantly lower for group A (p = .029) compared with group NA. No significant adverse effects were noted due to adrenaline usage. This study demonstrated that the use of adrenaline in a bilateral maxillary nerve block results in significantly lower intraoperative hemorrhage during cut and sew sharp staphylectomy and appeared safe to use. Potential clinical advantages include improved visualization, prevention of unnecessary blood loss and reduction in risk of blood aspiration.

HIPEDAP: Energy-Efficient Hardware Accelerators for Hidden Periodicity Detection

Hidden periodicity detection (HPD) forms the basis of various emerging and complex applications such as detecting tandem repeats in DNA and protein, absence seizure detection in EEG signals, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">etc.</i> The various solutions to the period estimation problem were not satisfactorily accurate until Ramanujan sums (RS) were recently used to explore the idea of periodic decomposition of signals. The use of Ramanujan sums in hidden periodicity detection was streamlined to form Ramanujan Filter Bank (RFB), but even then its usage in the applications proved to be computationally expensive. This paper proposes HIPED <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">AP</sub> , an efficient set of hardware accelerators for hidden periodicity detection applications using Ramanujan Filter Bank. HIPED <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">AP</sub> is developed by proposing several incrementally efficient microarchitectures targeting improvements in different aspects of the design such as area, power, and performance. We first propose a basic microarchitecture for the accelerator, Arch-A, which we then optimize and improve in terms of area, frequency of execution or power, in incremental steps to obtain Arch-E. These design improvements stem from various optimization techniques such as different filter structure realizations, transposition, pipelining and implementation of a fast division circuit. Further, the inherent error resilience exhibited by HPD applications enables us to propose an approximate architecture, Arch-F, that synergistically applies multiple approximation techniques such as approximate adder, multiplier, and precision scaling on top of Arch-E, resulting in significant performance and energy benefits. Experimental results obtained after synthesizing and mapping the hardware implementation of the microarchitectures on 45 nm technology demonstrate that the optimized Arch-E design is able to achieve 4.7X, 8.2X and 1.7X improvements over Arch-A in terms of area, frequency of execution and power, respectively. On top of this, the approximate Arch-F design demonstrated additional power savings of 14.6% on average (and upto 32.2%) over Arch-E for almost no loss in application-level quality. Finally, across a suite of practical applications, HIPED <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">AP</sub> exhibited a speed-up in the range of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$5.1 {\times } 10^{2}$</tex-math></inline-formula> X to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$3.2 {\times } 10^{4}$</tex-math></inline-formula> X with a geometric mean of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$3.7 {\times } 10^{3}$</tex-math></inline-formula> X compared to its software implementations.

Layout and yaw optimisation of an offshore wind farm through analytical modelling

In this work, a computational tool for analytical large scale modelling of offshore wind farms is presented. Using Horns Rev 1 as a reference baseline, an optimal layout and yaw angle setting for one wind direction based on aerodynamic considerations is proposed. Based on a wake model presented by Qian & Ishihara, flow velocities as well as turbulence intensities are predicted when several wake flows are superimposed. Subsequently, the aerodynamic performance of the wind turbines is calculated. The proposed tool shows good agreement with measurement and LES data. The influence of performance-driving parameters, namely turbine spacing, ambient turbulence intensity and yaw angle are investigated. The axial spacing and ambient turbulence are identified as the most significant factors. Based on these results, the proposed optimal layout solution suggests a higher power yield of up to 57 %, while the optimal yaw angles found in this work show a power increase of over 6% compared to the baseline layout.

Mechanical properties of atherosclerotic plaques, caps and walls of arterial vessels: a mobile test bench experiments

Within the framework of this study, a methodology and a prototype of a test bench for conducting experiments on compression of biological tissue samples have been developed. The test bench for the implementation of the technique consists of high–precision scales (measuring accuracy up to 0.01 g, maximum weight - 5 kg), an electronic caliper (measuring accuracy up to 0.01 mm) with 3D-printer pads that are attached to grips, as well as video cameras. Thanks to such a mobile stand, it was possible to conduct a series of experiments (a total of 99 tests) to determine the Young's modulus of atherosclerotic plaques and areas of vascular walls removed from the body no later than a few hours. This made it possible to collect a database of the mechanical characteristics of the plaques as close as possible to the real properties. In addition, regression dependences were constructed between the Hounsfield numbers corresponding to dense atherosclerotic deposits discernible on a CT scan and the Young modules obtained during experiments. Such dependencies will further allow determining the mechanical properties of plaques in vivo based on computed tomography data. The technique was verified by mechanical experiments on the universal testing machine Instron 3342 and on a mobile test bench on samples of hard (with pronounced calcification) and soft plaques. 7 experiments were conducted for each type of samples. The results differed by no more than 4.3 % for soft plaques and no more than 9.5 % for hard plaques. To test the inter-expert reliability of the methodology, a number of experiments were conducted with the involvement of two independent participants. Each of the three mobile stand operators performed 5 tests on soft rubber samples. The study of inter-expert reliability allowed us to show the independence of the methodology from the skills and qualifications of the operator.

Design of Portable High Precision Scale Hardness Tester Based on STM32

Hardness measurement is a very important index in the process of production and quality inspection. In the past, the precision of portable hardness tester is low, and the stability is poor. Combined with the internal high-speed ADC of the STM32 hardness tester can achieve a more demanding test accuracy requirements. Low power consumption, high accuracy and reliability of data acquisition is realized. And designed with the stemwin library can do more perfect function, human-computer interaction interface is more friendly.

Evaluation of hydrogen peroxide permeability, color change, and physical-chemical properties on the in-office dental bleaching with different mixing tip.

This study aims to assess hydrogen peroxide (HP) penetration into the pulp chamber, color change (CC), physical-chemical properties, and material wastage (MW) and material used (MU) in mixing tips when using in-office bleaching gels with two different mixing tips. Forty teeth were divided into five groups (n = 8) based on the bleaching gels used (Pola Office +37.5% [PO+] and Whiteness HP Automixx Plus 35% [AM+]) and the mixing tip types (T-Mixer and Helical). A negative control group was treated with ultra-purified water. HP concentration was measured using UV-Vis, and CC was evaluated with a digital spectrophotometer. Initial concentration, pH, and viscosity were measured through Titration, a Digital pH meter, and Rheometer, respectively. MW and MU were measured using a precise analytical balance. Statistical analysis included two-way ANOVA, Tukey's, and Dunnett's test (α = 0.05). A higher HP concentration was observed with PO+ with the Helical mixing tip in comparison with AM+ (p = 0.01). No significant differences in CC or MU were found for different mixing tips (p = 0.001). The T-mixer mixing tip resulted in significantly less MW (p < 0.00001) and improved mixture homogeneity and viscosity. Utilizing a T-mixer with self-mixing bleaching gels achieves comparable CC while reducing MW. Moreover, it decreases HP penetration when using PO+. For the application of a self-mixing in-office bleaching gel, a T-mixer mixing tip should be recommended, as it reduces the penetration of hydrogen peroxide into the pulp chamber when using PO+, while also minimizing gel wastage.

PENGARUH KONSENTRASI DAN INTERVAL WAKTU PEMBERIAN PUPUK ORGANIK CAIR AZOLLA TERHADAP PERTUMBUHAN DAN HASIL TANAMAN PAKCOY Varietas Nauli (Brassica rapa chinensis L.)

The aim of the research was to determine whether there was a real interaction effect of Azolla POC concentration and the time interval of POC administration on the yield and growth of Pakcoy plants. The research used a Randomized Group Design (RAK) arranged factorially including 2 factors which were repeated 3 times. Factor I is the nutrient dose of Azolla liquid organic fertilizer which consists of 3 levels 4 namely D1: 0 ml/1 water, D1: 2 ml/l water, D2: 4 ml/l water, D3: 6ml/l water and Factor II is Time interval for application of 3 level Azolla liquid organic fertilizer. S1: Application time interval 2 days, S2: Application time interval 4 days, S3: Application time interval 6 days. Plant height (cm) was observed at 0, 7, 14, 21, 28, 35 HST, measured using a meter. The number of leaves at 1, 3, 5, 7 and 9 WAP and leaf width at 0, 7, 14, 21, 28, 35 HST were measured using a tape measure. Accumulated fruit weight per plant (grams) The wet fruit weight of Pokcoy plants is determined by weighing all parts of the plant (roots, stems, leaves). Plants were weighed one by one using an analytical balance. Observational data were analyzed using Analysis of Variance (ANOVA) with a level of α = 0.05 and if there were significant differences between treatments then a further test was carried out using the DMRT test (Duncan's Multiple Range Test) at a level of α = 0.05. The results of research that have been carried out have concluded that there is a real interaction between the concentration of Azolla liquid organic fertilizer (D) and the time interval for POC application on the growth and yield of Pak Choy plants. The best treatment combination for plant height variables; number of leaves; leaf area is the D2S2 treatment, namely the combination treatment of azolla POC concentration of 4 ml/L and the POC application time interval of 4 days, while for plant fresh weight the best combination is D2S3, namely the combination treatment of 6 ml Azolla POC concentration and 4 day POC application time interval with weight. fresh plants amounting to 58.17 grams.

Basic electronic health record (EHR) adoption in **Türkiye is nearly complete but challenges persist

BackgroundThe digitalization studies in public hospitals in Türkiye started with the Health Transformation Program in 2003. As digitalization was accomplished, the policymakers needed to measure hospitals’ electronic health record (EHR) usage and adoptions. The ministry of health has been measuring the dissemination of meaningful usage and adoption of EHR since 2013 using Electronic Medical Record Adoption Model (EMRAM). The first published study about this analysis covered the surveys applied between 2013 and 2017. The results showed that 63.1% of all hospitals in Türkiye had at least basic EHR functions, and 36% had comprehensive EHR functions. Measuring the countrywide EHR adoption level is becoming popular in the world. This study aims to measure adoption levels of EHR in public hospitals in Türkiye, indicate the change to the previous study, and make a benchmark with other countries measuring national EHR adoption levels. The research question of this study is to reveal whether there has been a change in the adoption level of EHR in the three years since 2018 in Türkiye. Also, make a benchmark with other countries such as the US, Japan, and China in country-wide EHR adoption in 2021.MethodsIn 2021, 717 public hospitals actively operating in Türkiye completed the EMRAM survey. The survey results, deals with five topics (General Stage Status, Information Technology Security, Electronic Health Record/Clinical Data Repository, Clinical Documentation, Closed-Loop Management), was reviewed by the authors. Survey data were compared according to hospital type (Specialty Hospitals, General Hospitals, Teaching and Research Hospitals) in terms of general stage status. The data obtained from the survey results were analyzed with QlikView Personal Edition. The availability and prevalence of medical information systems and EHR functions and their use were measured.ResultsWe found that 33.7% of public hospitals in Türkiye have only basic EHR functions, and 66.3% have extensive EHR functions, which yields that all hospitals (100%) have at least basic EHR functions. That means remarkable progress from the previous study covering 2013 and 2017. This level also indicates that Türkiye has slightly better adoption from the US (96%) and much better than China (85.3%) and Korea (58.1%).ConclusionsAlthough there has been outstanding (50%) progress since 2017 in Turkish public hospitals, it seems there is still a long way to disseminate comprehensive EHR functions, such as closed-loop medication administration, clinical decision support systems, patient engagement, etc. Measuring the stage of EHR adoption at regular intervals and on analytical scales is an effective management tool for policymakers. The bottom-up adoption approach established for adopting and managing EHR functions in the US has also yielded successful results in Türkiye.

Generation of renewable hydrogen from sewage sludge — Quantitative and energy-based technology evaluation

The paper presents a critical analysis of a commercial pre-feasibility study for hydrogen generation from sewage sludge generated in a wastewater treatment plant sized Population Equivalent (PE) = 160,000 Three commercial offers based on hydrothermal carbonization, gasification/plasma gasification and gas separation, are analysed and validated in terms of chemical reactions and energy balance. The obtained hydrogen yield equals 10 kg H2/Mg sludge for Technology#2 and 5.5 kg H2/Mg sludge for Technology#3, while the process efficiency equals 31.4% and 41.2%, respectively. The offer for Technology#1 is inconsistent. The potential market can be built in the transport sector, based on buses (8–12/day) or locomotives (1–2/day) and complemented by passenger cars (16–22/day). Hydrogen surplus can be disposed into the natural gas network at a city gate station, with target concentration <2%. Alternatively, it is possible to install a fuel cell unit for on-site electricity generation of 1780 MWh/a sold to the public grid.

Simultaneous estimation of Azelnidipine and Metoprolol succinate with greenness assessment using HPLC and UV-spectrophotometric methods

Azelnidipine is a novel dihydropyridine calcium channel antagonist and Metoprolol succinate is a beta blocker, this combination was approved by CDSCO for Phase III clinical trial in April 2021. This combination is utilized to achieve a better outcome in the treatment of stage 2 hypertension. The present research includes an HPLC and Absorbance Correction UV method for the determination in synthetic mixture.The HPLC chromatography was performed using a gradient technique on a reversed-phase C18 column with mobile phase based and optimized depending on the polarity of the molecules. The Unesphere C18 column Agela Tech., (250 mm x 4.6 mm i.d, 5 μm,) as stationary phase and Acetonitrile: Phosphate Buffer pH 3.5 (40:60%v/v) as mobile phase with UV detection at 275 nm at 1 ml/min for gradient elution was used to achieve chromatographic separation over the linearity 10.0 - 30.0 μg/mL and 50.0–150.0 μg/mL with r2 0.9995 and 0.9993 for Azelnidipine and Metoprolol succinate respectively. The retention time was found to be 6.367 and 2.308 min for Azelnidipine and Metoprolol succinate respectively.% RSD of intraday precision of AZL and MET was found to be 0.01 – 0.03% and 0.01 – 0.03%, respectively. Interday presion was found to be 0.02 – 0.06% and 0.02 – 0.05%, respectively which are indicated that the method is precise.% recovery for AZL and MET by this method was found in the range of 99.85 - 100.76% and 99.23 - 99.89%, respectively. The system suitability test parameters theoretical plates were found to be 7042.56 (AZL) and 2231.74 (MET) and tailing factor was found to be 1.47 (AZL) and 1.52 (MET).The Absorbance Correction UV method was developed validated at 313 nm (λmax of Azelnidipine) and 275.40 nm (λmax of Metoprolol succinate) in methanol: distilled water (20:80, v/v) for estimation of AZL and MET respectively and show linearity 5.0 - 25.0 μg/mL and 25.0 - 125.0 μg/mL with r2 0.9998 and 0.9991 for Azelnidipine and Metoprolol succinate respectively.% RSD of intraday precision of AZL and MET was found to be 0.46 – 0.64% and 0.42 – 0.71%, respectively and for interday precision was found to be 0.40 – 0.65% and 0.22 – 0.75%, respectively.% recovery for AZL and MET by this method was found in the range of 100.50 - 100.77% and 100.30 - 100.78%, respectively. The value of% RSD within the limit indicated that the method is accurate and% recovery shows that there is no interference from the excipients.Both methods were validated as per ICH Q2(R1) guidelines. The analytical method validation parameters were found to be as per acceptance criteria. In terms of accuracy and precision, statistical testing employing an analysis of variance test did not find any significant differences between the two methods. The ICH Q2R1 recommendations extensive statistical validation of the two established methodologies, proving their effective use in the simultaneous study of the two medications in bulk and tablets made within the laboratory.The Analytical eco scale (AES), National environmental method index (NEMI), Green analytical procedure index (GAPI), and software-based Analytical greenness metric (AGREE) tools were used to assess the ecological impact of the new UV spectrophotometric technique and HPLC method. This assessment confirmed the method's environmental friendliness in terms of solvent usage, chemical compounds, energy consumption, and trash creation. Both methods can be used to successfully analyze Azelnidipine and Metoprolol succinate in combination dose form without interference from excipients. There were no spectral or chromatographic interferences from formulation excipients discovered. Because the proposed procedures are simple, quick, precise, and accurate, they were effectively used to determine Azelnidipine and Metoprolol succinate in their dose forms. To evaluate the greenness and whiteness of an analytical method, a reliable assessment of the health and environmental risk associated with chemical use is essential. An objective and useful way of risk assessment should consider all pertinent characteristics of substances utilized, the actual quantities required for method implementation, and the result of the assessment should be quantified using a standard unit.

Unique green chromatographic method for the qualitative and quantitative analysis of ketoconazole, its impurities and preservatives from ketoconazole cream formulation: Identification of degradants by Q-ToF LCMS and Robustness by Design of Experiments

Current research portrays a simultaneous determination method for the qualitative and quantitative analysis of Ketoconazole, its impurities and preservatives from Ketoconazole cream formulation. The unique method was developed using the RP-UPLC technique with a gradient elution mode. The separation of isomeric preservative components was achieved on the Waters Acquity UPLC BEH C18 column using phosphate buffer as mobile phase A and a mixture of phosphate buffer and acetonitrile, 30:70 (v/v) as mobile phase B. The set flow rate, injection volume, column oven temperature, and detector wavelengths were 0.5 mL/min, 2.0 μL, 30 °C, and 225 nm, respectively. The method's stability indicating nature was achieved through forced degradation studies. The active drug was prone to acidic and oxidative conditions. The attained acidic and peroxide degradant peaks were identified using Q-ToF LCMS. The developed method was validated per regulatory guidelines, and the data showed superior precision with a %RSD of 0.7 for Ketoconazole, 0.8 for preservatives, and 1.6 for impurities. All the components showed excellent linearity (r > 0.999) within the 50–150% range for Ketoconazole and preservatives and from LOQ to 150% for impurities. The mean accuracy data resulted from 99.4% to 99.9% for Ketoconazole, 99.9%–106.0% for impurities, and 100.3%–101.4% for butylated hydroxyanisole. The robust method conditions were evaluated by the Design of Experiments. The greenness and eco-friendliness of the method were demonstrated by modern tools such as the analytical eco scale, GAPI and AGREE. The final UPLC method is specific and suitable for determining the preservatives, drug content and impurities of Ketoconazole simultaneously from its cream formulation, which saves analysis time and solvent consumption supporting towards the green chemistry principles.

Virtual chiral recognition of eugenol derivatives on amylose tris(3-chloro-5-methylphenylcarbamate) chiral stationary phase in unusual normal-phase mode

Chromatographic enantioseparation on polysaccharide-based chiral stationary phases has undergone explosive development over the last three decades as a method for separating the enantiomers of chiral compounds on an analytical and preparative scale. In this context, understanding the nature of the intermolecular interactions involved in retention and recognition processes is an interesting scientific challenge. In the present study, three eugenol derivatives were used as chiral references to elucidate some unexplored aspects of the enantioselective and retention properties of the Chiralpak IG-U chiral stationary phase based on amylose-tris(3-chloro-5-methylphenylcarbamate).The performance of the ultra-high performance liquid chromatography chiral packing material Chiralpak IG-U was evaluated using a two-step approach. First, binary mixtures containing variable proportions of alcohol (ethanol or 2-propanol) in n-hexane were used as mobile phases and the retention factors were recorded at three different temperatures. A rational analysis of this set of chromatographic data shows the leading role played by hydrogen bond between the OH group linked to the stereogenic centre of the analytes and the active sites of the chiral chromatographic material in obtaining a high degree of enantioseparation.The retention factors were then plotted against the percentage of alcohol modifiers to obtain retention maps with a non-linear performance trend with correlation factors >0.9990.The proposed retention map model was used to extrapolate and describe virtual chiral recognition of chiral analytes on the Chiralpak IG-U chiral stationary phase under extreme elution conditions with expected run times of hundreds or thousands of years. The presented virtual chiral recognition approach is based on a generic concept and therefore opens new possibilities for understanding the performance of other polysaccharide-based chiral stationary phases.

China’s digital infrastructure: Networks, systems, standards

In the People’s Republic of China, the development of information infrastructures has been a cardinal component of the national modernization project for more than four decades. While most discussions of digital infrastructure in the country focus on the ‘Chinese internet,' framed by architectures of control like the Great Firewall and governmental initiatives like Internet Plus, this special issue contends that China’s digital infrastructure extends from the physical cables laid under urban streets to the ideological capture of surveillance systems, and from the smart home devices domesticated by elderly citizens to the QR codes plastered on everyday life surfaces. Through their interdisciplinary and innovative studies, this issue’s contributors push discussions of China’s digital infrastructure beyond the reduction to authoritarian control and the triumphal rhetorics of governmental imaginaries. Given the breadth of analytical scale and the variety of research methods featured in this collection, the nine contributions to this special issue are organized in three clusters, each centered around one of three key terms from infrastructure studies: networks, systems, and standards. By accounting for heterogeneous scales and relationships through which China’s digital infrastructure emerges, consolidates, and falls apart, these articles produce original knowledge about complex sociotechnical processes and develop productive concepts for future scholarship.

Solid particle erosion evaluation of automotive paint coatings under the influence of artificial weathering

Solid particle erosion (SPE) is one of the most critical tribological problems causing damage to automotive paint coatings. The correct characterization of SPE and resistance against it makes the possible extended service life of the coating, increasing the resale value of cars. Car manufacturers and paint industries have developed new techniques to apply coatings and coatings that improve the initial and long-term appearance, scratch performance, and durability of coatings. Several works have focused on studying the degradation and performance of paint coatings. However, there needs to be more understanding of wear progress under different environmental degradation conditions. This study investigates the mechanisms and resistance of erosive wear of actual automotive paint coatings before and after exposure to an accelerated weathering process. Steel substrate panels with a typical paint coating system were exposed to weathering degradation by UV and immersion in an artificial acid rain solution. The chemical changes induced in the coatings were analyzed by FT-IR spectroscopy. Then erosive tests were carried out using silica sand particles at two different angles of incidence (30° and 90°) and temperatures (25 °C and 60 °C) for both samples (unexposed and weathering conditions). The SPE rate was determined for each coating by mass loss estimation using an analytical balance; meanwhile, wear mechanisms were analyzed in detail by SEM. The results showed decreased SPE resistance promoted by chemical changes in samples exposed to both weathering processes.

Circular RNA ciRS-7 signature as a potential biomarker for the early detection of diabetes with Alzheimer's disease: a hypothesis.

In the 1970s, Circular RNAs (CircRNAs) were first discovered in RNA viruses as viroids and were initially assumed to be RNA splicing defects. The roles and topologies of these circular RNA loops were later revealed using computer analysis and RNA-sequencing. They were found to demonstrate various functions, including protein scaffolding, parental gene regulation, microRNA sponges, and RNA-protein interactions. CircRNAs play a crucial role in controlling gene expression and are essential for biological development and illness detection, as demonstrated by their roles as miRNA sponges, endogenous RNAs, and potential biomarkers. Insulin resistance is caused by damage to β-cells in the pancreatic islets, which reduces the body's response to the hormone insulin. This reduction in insulin response hinders glucose from entering cells and providing energy for critical processes. As a result, insulin-resistant cells elevate blood sugar levels, leading to diabetes. Diabetes, in turn, increases the risk of heart disease and stroke, which can damage the heart and arteries. Additionally, an excess of insulin can impact the brain's chemical balance, contributing to the development of Alzheimer's disease. Furthermore, oxidative stress created by damaged pancreatic cells during high blood sugar conditions may lead to the destruction of brain cells and the onset of Alzheimer's disease. The hypothesis of this review is to provide an overview of the most dominant ciRS-7 circRNA identified in pancreatic islet cell dysfunction and neurologic disorders, such as Alzheimer's disease. By considering ciRS-7 circRNA as a potential biomarker for diabetes, early detection and treatment of diabetes may be facilitated, potentially reducing the risk of Alzheimer's disease onset in the future.

Перспективи застосування електрохімічного полірування зразків скеффолд, виготовлених за адитивною технологією

In recent years, the actual production of metal products directly from electronic data according to a three-dimensional model based on layer-by-layer manufacturing has evolved from rapid prototyping to additive manufacturing. As the quality of additively manufactured metal products continues to increase and their manufacturing processes improve and develop, the demand for additive manufacturing is increasing. Additive manufacturing technology, also known as 3D printing, has become increasingly popular recently. Using additive manufacturing, almost any complex geometry can be manufactured with high degree of precision. After the production of parts using the SLM technology from metal powder, post-processing is applied, in particular electrochemical polishing, the main purpose of which is to reduce surface roughness, increase the gloss of surface elements, and remove metal powder that has partially melted onto the outer surface of the product at the point of contact between the molten metal and the border of the part and the powder, which is located next to the melt. This is especially important for inclined surfaces, internal channels and cellular structures with developed outer surface. For research, samples were made using SLM technology from AISI 316L austenitic steel powder. The samples have a cube shape with a base of 10 mm, a height of 10 mm, and a thickness of 10 mm, with cell widths of 4 mm and 2 mm. The main body of both samples was printed using the same modes at a laser power of 220 W, a scanning speed of 1000 mm/s and a distance between laser passes of 0.14 mm. Samples were printed on Alfa-280 3D printer manufactured by ALT Ukraine LLC. Electropolishing was carried out in a solution of orthophosphoric acid (H3PO4) with glycerol (C3H8O3) by immersing the test samples in the electrolytic solution at a voltage of 17 V and a current density of 3 A/cm2. The control of weight and geometric parameters was carried out with the help of ADV-2000 analytical balances and MKC-25 micrometer. The electropolishing of the experimental samples took place in four stages: 1) visual - optical inspection with fixation, weight control before the start of the process; 2) electropolishing for 3 minutes, visual - optical inspection with photo fixation; weight control after 3 min. polishing process; 3) electropolishing of the same samples for another 3 minutes, visual – optical inspection with photo fixation, weight control after 6 minutes. polishing; 4) electropolishing of the same samples for another 3 minutes, visual - optical inspection with photo fixation; weight control after 9 min. electropolishing process. At each stage, a real current-voltage curve was recorded using an oscilloscope. As a result of weight control before and after the test, it was established that the samples lost approximately the same weight in the range of 6.9...7.1 % relative to the initial one. Based on the analysis of the obtained results, it was established that at a current density of 3 A/cm2 and at a voltage of 17 V, effective active uniform polishing of the surface of samples with a cellular structure of scaffold type with a variable cell size from 4 to 2 mm is realized.

Assessment of debris extrusion on using automated irrigation device with conventional needle irrigation – An ex vivo study

Introduction: Irrigation is an essential aspect of effective cleaning and disinfecting the root canal system. Debris tends to extrude in due course of instrumentation and irrigation. The present study aimed to assess the debris extrusion using an automated root canal irrigation device. Materials and Methods: Sixty-six intact maxillary premolars with double-rooted morphology undergoing extraction were collected. They were allocated into three groups – Group I: control (distilled water irrigation), Group II: conventional needle irrigation, and Group III: automated root canal irrigation (n = 22). Each specimen was then inserted into the Eppendorf tube for debris collection. The canals were then instrumented to 40 size 0.04 taper using HyFlex CM rotary file system. Experimental irrigation varied based on the specific group allocated. Finally, after the irrigation, the collected debris was weighed using the analytical balance. Results: A statistically significant difference (P &lt; 0.05) was elicited in the debris extrusion scores seen among different groups assessed. Conclusion: Debris extrusion was minimal with automated root canal irrigation device as compared to syringe needle irrigation.