bluuebunny/crossref_metadata_2025 huggingface dataset:
Symmetry-Breaking in a Porous Cavity with Moving Side Walls
Authors: Menacer Dalila , Boudebous Saadoun , Slimani Abdeldjalil , Saihi Lakhdar
Published: January 2022

In this paper, a numerical investigation of the steady laminar mixed convection flow in a porous square enclosure has been considered. This structure represents a practical system such as an external through flow of cooled-air an electronic device from its moving sides. The heating was supplied by an internal volumetric source with an uniform distribution at the middle part of its bottom, while the other walls were assumed thermally insulated. Moreover, the momentum transfer in the porous substrate was numerically investigated using the Darcy-Brinkman-Forchheimer law. The governing equations of the posed problem have been solved by applying the finite difference technique on non-uniform grids. For all simulations, the Reynolds number and the porosity have been fixed respectively to Re=100 and φ=0.9. Darcy’s value was varied in the range from 0.001 to 0.1. The results detected the existence of a radical change in the contour patterns for Richardson number equal to 11.76 and 11.77 with fixed Da=0.1. This behavior signified that the fluid is fully convected for higher Darcy number.
Competitive Adsorption of Copper, Zinc, and Chromium from Wastewater Using Corn-Cob Ash: Optimization Approach
Authors: Ugwu Emmanuel Ikechukwu , Agunwamba Jonah Chukwuemeka
Published: January 2022

Corn Cob ash was used in competitive adsorption of copper, zinc, and chromium from wastewater. The central composite design; a sub-set of response surface methodology was used to optimize the adsorption of the heavy metals. The result of the statistical parameters showed the coefficient of determination (R2) of 1.000, 0.999, and 1.000 for copper, zinc, and chromium respectively. The optimal conditions obtained for adsorbent dosage, initial concentration, temperature, contact time, and particle size were 13.20 mg, 79.72 mg/l, 34.95 °C, 40.38 min, and 1400 µm, respectively with the desirability of 1.000. The predicted and the actual values of metal removal obtained were 69.41%, 76.37%, as well as 70.44%, 72.50%, 77.90 % and 71.00% for copper, zinc, and chromium respectively. The ressult indicated a good conformity between the model predicted values and the actual values, thus having small errors of 3.09%, 1.53 % and 0.56 % for copper, zinc, and chromium respectively.
Two Approaches to the Study of Temperature Effect on the Dissipative Properties of Materials
Authors: Petrosyan Tigran
Published: January 2022

In order to study the effect of temperature changes on the dissipative properties of materials, two approaches are used. The first approach implies introducing some temperature function under the sign of the integral in the heredity theory equation and simultaneously taking into account the dependence of the elastic modulus on temperature. As a result, based on experimental data on the thermal creep of soils, the expression for determining the hysteresis energy losses under the periodic voltage changes was obtained depending on temperature changes.According to the second approach, the expression for determining the hysteresis energy losses under isothermal conditions at different temperatures was obtained by introducing into the heredity theory equation an approximation of the experimental dependences of instantaneous deformation and temperature creep parameters for steel Kh18 N10T.
Simplification and Improvement of the Efficiency of Testing Thermophysical Properties of Facade Composite Materials
Authors: Karamyan Anna , Movsesyan Karen , Manukyan Tigran
Published: January 2022

The choice of highly efficient materials for the opaque parts of the building facades is the most effective factor in increasing its thermal protection. A decrease in the coefficient of U-value of opaque parts of a building directly affects the consumption of both thermal energy and the energy demand for cooling. Two-component or multi-component composite materials today occupy a large place in modern construction. This article analyzes the methodology for testing the thermophysical properties of these materials, reveals a new approach to determine to it, taking into account the links between the thermal conductivity and the thermal diffusivity of materials. The article analyzes the relationship between buildings and the surfaces of the outer envelope and the dependence of the energy efficiency index of the building.
Electroplating of Indium-Cadmium and Tin-Cadmium Alloy Coatings
Authors: Kireev Sergey Yu. , Kireeva Svetlana N. , Frolov Anatoly , Yangurazova Alfiya , Anopin Konstantin
Published: January 2022

Technological parameters for electroplating cadmium alloy (Cd (24)-In and Cd (33)-Sn) coatings from low toxic solutions have been proposed. Since the fabricated alloy coatings possess low internal stress and microhardness, good adhesion property, high corrosion and wear resistance, they can be used as protective coatings for machine building products to enhance reliability and operability thereof. The presence of good solderability and low values of transient electric resistance in climatic testing favor these coatings to be applied in hetero-structured contact systems of instrument making products for increasing their reliability and operability in a tropical marine climate.
Selection of Nanostructured Zirconium Dioxide Crystals under Dry Friction against Molybdenum
Authors: Alisin Valery V.
Published: January 2022

The article considers the issues of contact interaction of nanostructured zirconium dioxide crystals with molybdenum coating on titanium-based alloy ВТ9. The following statement is substantiated: the best mechanical properties of crystals correspond to the total amount of 2.8% additives of stabilizing and doping rare earths elements. Antifriction properties of crystals under dry friction against molybdenum are investigated. Tribological testing was performed on a reciprocating friction gauge simulating the operation of a plunger in a cylinder. The high scoring resistance of the friction couple under study was experimentally proved; the friction coefficient did not exceed 0.07. On the basis of the study performed, the friction couple is defined as promising for increasing the lifetime and reliability of friction units for hydraulic equipment and fuel pumps.
Magneto-Optical Properties of Rare-Earth Terbium Ferrite-Garnet in the Near the Temperature of the Orientation Phase Transition
Authors: Sharipov Mirzo Z. , Hayitov Dilshod E. , Rizoqulov Mirzohid N.
Published: January 2022

A model of the rearrangement of the domain structure of the Tb0.2Y2.8Fe5O12 garnet ferrite in the temperature region of the spontaneous reorientation of the easy magnetization axis is proposed, which makes it possible to consistently describe (at a qualitative level) the entire set of experimental results obtained. The latter makes it possible to make a choice in favor of the fluctuation mechanism of nucleation of domains of a new magnetic phase in the process of reorientation of the direction of the easy magnetization axis.
Methodology for the Selection of Technological Modes for the Synthesis of Transparent Conducting Oxides with Desired Properties
Authors: Zinchenko Timur O. , Pecherskaya Ekaterina A. , Antipenko Vladimir V. , Volik Artem V. , Varenik Yuriy A. , Shepeleva Anastasiya E.
Published: January 2022

Transparent conducting oxides (TCOs) are widely used as a transparent electrode in various fields of opto-and semiconductor electronics. The main materials used today are indium-tin oxide, tin-antimony oxide and zinc-aluminum oxide. The authors have developed and improved the spray-pyrolysis method, which is one of the most promising methods of implementation in production. In this work, the study of tin dioxide doped with antimony coatings and the development of a methodology for the controlled synthesis of TCO, taking into account the effect of technological modes of deposition on the TCO parameters. The results of the performed studies contribute to the development of an automated technology for the synthesis of transparent conducting oxides with desired properties.
Identification of the Mechanism of Synthesis of SDRL Rubber
Authors: Garifullina Elvira , Manuyko Galiya , Aminova Guzel , Bronskaya Veronika , Balzamov Denis , Ignashina Tatiana , Kharitonova Olga
Published: January 2022

Modelling and identification of the synthesis of SDRL rubber in the presence of toluene and modifier was carried out. The mechanism of the polymerization of butadiene on the lithium catalytic system. One of the most characteristic differences between the processes of ionic, in particular, anionic, polymerization and radical polymerization is that even when using initiators that seem to be individual, several forms of active centres, that differ in their reactivity, can simultaneously be present in systems.
Application of the Acoustic Emission Method for Estimating the Residual Life of Elastic Elements at the Stage of Preparing a Product for Operation
Authors: Remshev Evgeny , Gusev Artem , Voinash Sergey , Vornacheva Irina , Scherbakov Alexander , Kuzmin Oleg , Sokolova Victoria Alexandrovna
Published: January 2022

The article discusses the experimental substantiation of predicting the operational properties of elastic elements by the acoustic emission (AE) method, as well as the use of the non-destructive method of acoustic emission as an element of digital certification of critical mechanical and instrument engineering products.
Mapping of Beta Distribution for the Study of Dispersed Materials
Authors: Polosin Vitaly
Published: January 2022

In the study of polydisperse materials, most of the experimental particle size distributions were obtained on bounded intervals. In these cases, it is also desirable to use bounded models with different shapes to simulate the results of studying polydisperse and powder materials. The beta distribution is often used to approximate results due to the fact that this distribution contains many forms for displaying realizations on a limited interval. With the development of computer technology, there has been an increased interest in the use of beta distribution in the modern practice of analyzing results. Meanwhile, there remains a limitation in the use of the beta distribution that is associated with the choice of distribution shape. The possibilities of using known shape measures for mapping beta distribution in this paper is discusses. On the example of the space of shape measure of kurtosis and skewness, the limited use of only probabilistic measures of shapes is illustrated. It is proposed to use the entropy coefficients as an additional informational parameter of the beta distribution shape. On the base of a features comparison of the entropy coefficients for biased and unbiased beta distributions, recommendations for their application are given. By using the example of beta distributions mapping in the space of asymmetry and the entropy coefficient, it is shown that the synergistic combination of probabilistic and informational measures of the shape allows expanding the possibilities of estimating the shape parameters beta distributions. Two methods to display the positions of realizations of beta distributions is proposed. There are trajectories on a constant ratio of shape and realizations position curve on equal values of one parameter. In particular, the features of the choice of beta distributions with negative skewness are discussed.
Determination of the Causes of Copper Wires Beads after Fire in Vehicles
Authors: Mokryak Andrei Yu. , Mokryak Anna V. , Skodtaev Soslan V. , Safonova Tatiana V.
Published: January 2022

An electrical installation that simulates an automobile DC power supply system with a voltage of 12 V has been created. An experimental simulation of a short circuit at currents up to 400 A on copper multi-wire and single-wire conductors under normal environmental conditions is carried out. The copper wires beads were annealed in a furnace at temperatures from 700 to 1000 °C for 20, 40 and 60 minutes. Metallographic analysis of copper wires beads was carried out. The temperatures and times that of at which the signs of short circuit and overcurrent are destroyed has been revealed. Obtained results contribute to improvement evidence’s researching in the fire investigation of motor vehicles electrical wiring after a fire. Keywords: Arc beads, Copper, Metallographic analysis, Electrical Short Circuit, Wires.
Influence of Ultrasonic Waves on Current-Voltage Characteristics and Polarization Effects of Si-N-P Radiation Receivers
Authors: Gaibov Abdumalik G. , Vakhobov K.I. , Ibragimova B.V. , Zhuraev U.E. , Rasulova D.T.
Published: January 2022

The currents of n-p junctions and polarization effects caused by the capture processes of diffusion Si-receivers (detectors) of radiation exposed by ultrasound have been analyzed in this work. It was found that there are local concentrations of impurity atoms with an effective size l>6μm30μm in Si-n-p radiation receivers. They determine the behavior of the signal amplitude in different intervals of electric and temperature fields. It was found that at Е>1500V/cm and T>168K, the efficiency of collecting nonequilibrium charge carriers significantly increases and doublets of spectral α-lines and “humps” disappear at the temperature dependences of the signal amplitude. The main physical processes and mechanisms that determine the appearance of the phenomenon of "polarization" of Si-n-p-detectors were investigated. This phenomenon is caused by the existence of local gold atoms, which arise in the process of manufacturing technology of Si-n-p-receivers and act as effective trapping centers.
Reconstruction of Regression Relationships for Determination of Strength Values for Alloys of Products in Diffusion Welding
Authors: Kurashkin Sergei , Rogova Daria , Lavrishchev Alexander , Tynchenko Vadim Sergeevich , Murygin Alexander
Published: January 2022

The article deals with the problem of obtaining the dependence of the product strength parameter on the welding time, welding temperature and pressure during mechanical tests, leak tests. The relevance of this work is due to the complexity of carrying out field experiments to identify dependencies. In particular, the complexity arises from the duration of diffusion welding and the high cost. Application of the method of regression analysis based on a non-compositional plan of the second order for three factors will allow to restore the dependence of the product strength parameter on the time during which welding was carried out, the temperature at which diffusion welding was carried out or could be carried out and on the applied pressure at which mechanical tests were carried out. In the current study, a non-compositional design of the second order for three factors was used - allowing to restore the dependence of the missing values of the strength of the product. The aim of the research is to improve the quality of mathematical modeling. Application of the proposed approach will make it possible to obtain the strength distribution function depending on time, temperature and pressure using the example of a product made of VT14 titanium alloy and 12X18H10T stainless steel. This will make it possible to obtain optimal parameters for the diffusion welding mode and to improve the quality of the resulting products.
Calculation Strategies of Molar Ratio Based Homeopathic Dilutions and the need for Pharmaceutical Scientists' Engagement
Authors: Ranasinghe K. D. E. P. , Pathirana W.
Published: January 2022

Purpose: A deficit was identified in the traditional method of making homeopathic dilutions by 1:9 or 1:99 serial dilutions based on the physical units of mass or volume. When the chemical unit mole is considered, the 1:9 mass-based dilution of nitroglycerin in ethyl alcohol has a 1:48.8 molar ratio. In order to provide the 1:9 molar ratio, the mass ratios required for formulations with lithium carbonate: lactose (diluent) and lead phosphate: lactose are 1:41.7 and 1:3.8 respectively. The extreme incongruity between the mass and the volume-based 1:9 ratios and the ratios based on chemical unit mole show the need to adopt the later scheme which is based on sound principles of chemistry.
Method: Detailed calculations in determining the 1:9 molar ratio of drug: diluent are explained. Method for the molar ratio calculation of chemically less defined medicines such as plant extracts are proposed.
Results: A Molar Ratio Universal Formula for the calculation of the amount of diluent to be used in preparing a given potency of a homeopathic preparation is introduced.
Conclusion: The molar ratio dilutions based on principles of chemistry stand for wider acceptance of homeopathic medicines by the scientific community and for the advancement of the homeopathic system of medicine.
Assessing the Mediation Role of the Customer Trust On E-Service Quality: Lessons During Covid-19 Pandemic
Authors: Gunawardana P. K. A. T. D. R. , Fernando P. I. N.
Published: January 2022

Online groceries or e-groceries were highlighted as one of the effective means to avoid personal contacts and maintain social distance during the Covid-19 Pandemic. Thus, this paper focuses on the insight on the impact of e-service quality dimensions and customer satisfaction of e-groceries with the role of customer trust as a mediating variable during the epidemic. A quantitative approach has been adopted where the empirical data gathered from 300 e-grocery shoppers in Western province, Sri Lanka while adopting the multi-stage sampling technique. A field survey was conducted during the first wave of the Covid-19 pandemic during March-June 2020. Regression analysis was the main analysis method whereas the Barron and Kenny mediator analysis and Sobel test were adopted for mediation impact. Findings highlight, e-service quality dimensions strongly impact the customer satisfaction of e-groceries during the Pandemic whereas customer trust partially mediates the e-service quality and customer satisfaction of e-groceries. Implications focused on; (a) e-grocery service providers have to distinct on revamp of customer trust parameters, (b) e-service quality dimensions to enhance the customer satisfaction, customer trust, and (c) attract more customers for e-grocery shopping.
ETHNIC AND TRIBAL GROUPS, BORDERS AND FRONTIERS, RESOURCES AND GOODS. MAPS TO UNDERSTANDING AFGHANISTAN
Authors: Piacentini Fiorani Valeria
Published: January 2022

Non disponibile.
Impact of Atrial Fibrillation on the Severity, Progress, and Disability of the Ischemic Stroke Patients
Authors: Mavromoustakou Kiriaki , Doundoulakis Ioannis , Soulaidopoulos Stergios , Arsenos Petros , Laina Ageliki , Sideris Skevos , Dilaveris Polychronis , Tsiachris Dimitrios , Kordalis Athanasios , Tsioufis Konstantinos , Gatzoulis Konstantinos A.
Published: January 2022

Background and Aim:

The association of atrial fibrillation (AF) with the ischemic stroke has emerged as an area of clinical research. The purpose of the present study is to investigate possible correlations between the severity, progress, and outcome of ischemic stroke and the presence of AF.

Materials and Methods and Results:

The clinical assessment of patients was based on the neurological status at the time of diagnosis utilizing the National Institutes of Health Stroke Scale (NIHSS), the neurological semiology during hospitalization (improvement, deterioration, and without differentiation), and the final outcome at the end of the treatment optimizing the modified Rankin scale (mRS). A total of 344 patients diagnosed with an ischemic stroke were enrolled in the study. The presence of AF was found to be associated with higher severity, poorer progress, and more adverse clinical outcomes of the ischemic stroke. Furthermore, a lower frequency of transient ischemic attacks was observed in patients with AF. Finally, patients with AF presented higher incidence of middle cerebral artery occlusion and were more frequently found with a lesion on the left brain hemisphere.

Conclusion:

AF was found to be highly associated with higher severity and poorer prognosis of ischemic strokes, independently from the presence of other cardiovascular risk factors.
Treatment effects and biomechanical analysis of TMA spring appliance
Authors: Eid Hany Salah Eldin , Elhiny Omnia A.
Published: January 2022

Background/Aim

Among Angle's classification, skeletal class III is the most difficult to treat. Treatment using the TMA spring intraoral appliance was investigated in the late mixed dentition and showed desirable effects. The present work aimed to investigate, biomechanically, the TMA spring appliance in the early mixed-dentition stage with specifically outlined force direction, duration, and magnitude in order to provide solid results that can be relied upon clinically.

Patients and methods

The sample consisted of 20 patients with an age range 8–10 years and an average of 8.6 years. Lateral cephalograms were taken and analyzed before treatment (T1), posttreatment (T2), and postretention (T3). The patients were instructed to wear the TMA spring appliance 12–16 h/day for 9 months, followed by 6 months of retention. The appliance delivered a force of 400 g/per side as measured with the force gauge.

Results

Comparing T1–T2 and T1–T3, there was a significant difference between sexes in points U6/S perpendicular; P=0013 and P=0.0159, SNA (P=0.0122, P=0.0371), and ANB (P=0.0491) at T1–T2. There was a significant difference in the whole sample for all the skeletal, dental, and soft-tissue measurements; P value less than 0.05, regarding treatment and retention changes.

Conclusions

The TMA spring appliance enhanced the cooperation of the patients, resulted in forward movement and clockwise rotation of the maxilla. Mandibular clockwise rotation and dentoalveolar changes also contributed to the overall correction of class III.
Atypical Migraine
Authors: Khattabi Marwa , Benatia Abdulbaset
Published: January 2022

Migraine is a chronic neurological condition that places a huge burden on patients and the society. Frequent headaches affect patients’ quality of life and interfere with their daily activities. Evidence suggests that migraine with aura can be associated with increased risk of having a stroke and other neurological complications; therefore, patients with migraine presenting with atypical symptoms present a complex medical challenge that would need further assessment in a hospital to exclude neurological conditions such as stroke or transient ischemic attack. We describe a case of a man who was evaluated at South Tees University Hospital, UK, and known to have chronic migraine with aura for 10 years. He presented to his general practitioner with new transient neurological symptoms and a different type of headache. This case reflects the level of diagnostic complexity and symptom overlap in patients presenting with atypical migraine, transient ischemic attack, and stroke.
Fogarty Catheter
Authors: Nandan Ruchira , Bajpai Minu , Yadav Devendra Kumar , Goel Prabudh
Published: January 2022

Introduction:

The extraction of smooth spherical objects is challenging as they are difficult to grasp within the jaws of the forceps and tend to slip distally.

Objective:

The authors herein have shared their experience with the use of a Fogarty catheter (FC) for safe extraction of smooth and spherical “foreign body (FB) with a hole.”

Materials and Methods:

Report on pediatric cases (n = 4) of airway “FB with a hole” wherein the FC was used for their extraction. Mean age was 27.5 months (range: 17 months–39 months). The male: female ratio was 3:1. The technique of FB extraction with a FC has been described, including the principle of the technique, indications, and contra-indications, technical problems and troubleshooting.

Results:

The FB spectrum included a necklace bead (n = 2), nonnecklace bead (n = 1) and a fragmented end-piece of the housing of a ball-pen (n = 1). The locations of the FBs were right main bronchus (n = 1), secondary bronchus on the right (n = 1), and in the left main bronchus (n = 2). Successful removal of FB with use of FC during rigid broncoscopy was possible. The bead had to be rotated in n = 2 patients to align the hole with the FC. Problems associated with threading the hole and disimpaction of the FB have been highlighted. No complications were observed. The advantages and limitation of the technique have been discussed.

Conclusions:

The use of FC with the described technique offers a safe, effective and reproducible method for removal of airway “FB with a hole” in a controlled environment while minimizing the possibility of iatrogenic injury to the wall of the surrounding airways.
Complete Tubular Colonic Duplication ending in a Common Channel as a Recto vestibular Fistula
Authors: Parveen Refat , Jester Ingo
Published: January 2022

Colon duplication (CD) is a rare congenital abnormality with varied presentations. We present a neonatal case with complete tubular CD terminating uniquely as a common channel, a single rectovestibular fistula. We summarize surgical management options in CD as well as factors that will help to decide the best surgical treatment in individual cases.
A 10-Year Study of the Outcome of Wilms' Tumor in Central India and Identifying Practice Gaps
Authors: Agrawal Vikesh , Mishra Arpan , Yadav Sanjay Kumar , Sharma Dhananjaya , Acharya Himanshu , Mishra Aradhna , Agrawal Rekha , Chanchlani Roshan
Published: January 2022

Introduction:

Despite remarkable improvement in Wilms' tumor (WT) survival in Western world, sub-optimal outcome in resource-constrained settings is influenced by late presentation, larger size, and poor access to treatment. This prompted us to study the outcome at a tertiary care center and to identify the global and local practice gaps.

Materials and Methods:

A retrospective, observational study of WT was conducted from October 2009 to September 2019 at a tertiary care setting. Following the National Wilms' Tumor Study Group protocol, an upfront nephrectomy (unilateral resectable tumors) and preoperative chemotherapy (large/unresectable Stage I–III) were followed. The records were reviewed for demographics, stage, preoperative chemotherapy, predictive factors, and outcome. Survival curves were plotted by the Kaplan–Meier method, and analysis was performed using the SPSS software version 16.

Results:

One hundred and fifty-six children were included, median age was 4.1 years, with a male predominance. The most common stages of the presentation were II (40.4%) and III (34.6%). An upfront surgery was done in 27.6%, while remaining received preoperative chemotherapy. The median follow-up was 22 months, and the events included relapse in 46 (29.48%) and death in 54 (34.61%). The mean survival time was 45.7 (95% confidence interval [CI], 41.08–50.30). The 2-year overall survival was 65.38% (95% CI, 59–73), and the 2-year event-free survival was 36% (95% CI, 32–41). On comparison of the impact of preoperative chemotherapy, the survival estimates in Stages I–III and relapse rate were statistically similar, tumor size reduced significantly, and tumor spill was significantly lower (P < 0.05).

Conclusion:

WT is associated with late presentation, sub-optimal survival, and higher relapse in our setting associated with practice gaps related to the management including practice violations.
Triplication of Ureter
Authors: Singh Teg Rabab , Dhua Anjan Kumar , Agarwala Sandeep , Yadav Richa , Kandasamy Devasenathipathy , Kumar Rakesh
Published: January 2022

Anatomical fusion abnormalities of the urinary system and ureters are not uncommon. However, triplication of the ureter is very rare. A boy with this abnormality is being presented in view of its rarity. The importance of a thorough preoperative evaluation is being projected that may help us to choose the best management avenue.
Primary hydatid cyst of the left-sided colon presenting with lower gastrointestinal bleeding; an extremely rare location of extrahepatic hydatid disease
Authors: Kafadar MT
Published: January 2022

Hydatid cyst is an endemic disease especially in underdeveloped and developing countries, affecting mostly the liver and lungs. However, a wide range of unusual anatomical sites in the abdomen have been reported, including the spleen, pancreas, kidney, and ovaries as well as dissemination within the abdominal and pelvic cavities. The location of hydatid disease in the colon is very infrequent, and very few cases have been presented so far. The hydatid cysts located in other sites are mostly due to rupture or extrusion of primary liver or splenic cysts. In this article, we present a case of primary left-sided colon hydatid cyst, resected laparoscopically with the affected intestinal segment. The diagnosis of hydatid cyst was made by macroscopic and microscopic examinations.
Comparative analysis of growth factors and chemokine secretions between conventional lingual and labial fixed orthodontic appliances
Authors: Baeshen Hosam Ali
Published: January 2022

Background:

Orthodontic appliances elicit the secretions of some cytokines, chemokines, and growth factors which further have some significances in the remodeling of periodontium tissues. The significant differential forces applied on the periodontium by different types of orthodontic appliances. The secretion of these factors is indirectly responsible for the proper resorption of bones of the periodontal region through molecular signaling, which further supports to facilitate organized movement of the teeth. Objective: In the present study, we carried out the assessment and comparative analysis of the growth factors and chemokines present in the saliva samples of the human subjects of orthodontic treatment with two different treatment modalities: conventional lingual and labial fixed orthodontic appliances.

Materials and Methods:

Total 40 saliva samples were collected of which 20 subjects were treated with the conventional lingual appliances and 20 subjects with the labial fixed appliances. All the salivary samples were acquired from the subjects after 21 days treatment. Cytometric bead array was performed to assess the growth factors and chemokines in the saliva on the flow cytometer.

Results:

No significant differences were seen in the growth factor secretion in the saliva of both types of subjects. The same trend was observed for the chemokine secretion in the saliva except CXCL8, CCL11, CCL2, CCL5, and CXCL9.

Conclusion:

The similarity in chemokine and growth factor profile between labial and lingual fixed orthodontic appliances indicates that their molecular mechanisms and overall effect on the periodontium are analogous.
The effect of dental anxiety on surgical time of mandibular third molar disimpaction
Authors: Suleiman AR , Efunkoya AA , Omeje KU , Amole IO
Published: January 2022

Background:

Dental treatment of anxious patients induces stress due to the patients' expectation of pain. This may prolong treatment due to such patients' inability to cooperate during treatment.

Aim:

The aim of the study was to determine the effect of dental anxiety on surgical time of mandibular third molar (M3) disimpactions at a Nigerian hospital.

Subjects and Methods:

A prospective study was conducted at the Oral Surgery clinic of Aminu Kano Teaching Hospital, Kano, between October 2016 and September 2017 to assess the effect of dental anxiety on surgical time of M3 disimpactions using the Modified Dental Anxiety Scale (MDAS). The Patients' biodata, clinical and M3 radiologic data were recorded. Surgical durations were also recorded. Data were analyzed with Statistical Package for Social Sciences for Windows (IBM statistics 23 software).

Results:

One hundred and sixteen subjects (64 males, 52 females) were studied. Forty-two subjects (36.2%) were mildly anxious, 67 (57.8%) were moderately anxious, and 7 (6.0%) were highly anxious. The females were more anxious and the overall surgical time (OST) of disimpaction correlated with the anxiety levels of the subjects. The OST increased by approximately 0.8 min with every unit rise in the anxiety score. Other factors that affected OST in the study were M3 depth, type of impaction, and root curvature.

Conclusion:

The patients' dental anxiety increased the surgical time of M3 disimpactions. Clinicians should consider the patients' anxiety among the factors that affect the surgical time of M3 disimpactions. Verbally soothing anxious patients and administering anxiolytic when necessary, may help to reduce the patients' anxiety, and hence, prevent surgical time prolongation.
A comparison of central corneal thickness measured using noncontact methods and ultrasonic pachymetry
Authors: Toptan M , Şimşek A
Published: January 2022

Aim:

The aim of this study is to compare central corneal thickness (CCT) measurements in healthy eyes using ultrasonic pachymetry (UP) with values obtained using anterior segment spectral domain optical coherence tomography (SD-OCT), the Scheimpflug camera system, and noncontact specular microscopy.

Material and Methods:

One hundred and twenty-five eyes of 117 healthy individuals (56 women, 61 men) were included. All patients underwent consecutive CCT measurement with UP, the Scheimpflug camera, anterior segment SD-OCT, and specular microscopy. The four devices could be read. Measurements from the four devices were classified in pairs and compared using the paired t-test. Relations between the devices were analyzed using the Pearson test. An alpha error level of P < 0.05 was regarded as statistically significant.

Results:

The mean age of the healthy individuals included in the study was 34.75 ± 14.55 years (20–76). Mean CCT values were 541.21 ± 29.24 μm with UP, 539.26 ± 29.27 μm with the Scheimpflug camera system, 532.21 ± 29.53 μm with SD-OCT, and 534.45 ± 29.20 μm with specular microscopy. The differences in measurements at the paired t-test were statistically significant (P < 0.001 for all). However, measurements using the four devices exhibited significant mutual correlation (P < 0.001 for all).

Conclusions:

CCT can be measured using different devices. Noncontact methods have now begun replacing UP, regarded as the gold standard. Although CCT values obtained from different devices were correlated, the difference between these measurements was statistically significant. Therefore, the same device should be used for measurement in the diagnosis and follow-up of diseases such as corneal ectasia and glaucoma where corneal thickness is important.
The effects of polymerization mode and layer thickness on monomer released from bulk fill composite resins
Authors: Cender E Uslu , Guler C , Odabasi D
Published: January 2022

Background:

Residual monomers released from composite resins have cytotoxic, mutagenic, and estrogenic effects. Mode of polymerization and application thickness are important for monomer release.

Aims:

The aim of this study was to investigate the effects of different modes of a third-generation light-curing unit (LCU) and layer thickness on residual monomer released from two different bulk-fill composite resins. A total of 80 samples were prepared for each bulk-fill composite using a mold. Each bulk-fill composite was divided into four groups according to polymerization mode (standard and extra power) and layer thickness (2 and 4 mm). In addition, four groups were divided into four subgroups according to time periods (1 h, 24 h, 3 days, and 7 days).

Methods and Material:

The samples were polymerized with VALO LED device. The amount of residual monomer was measured with High-Performance Liquid Chromatography (HPLC). All statistical analyses were processed using SPSS Version 23.0. The normal distribution of data was confirmed using Kolmogorov–Smirnov Normal Distribution Test and Shapiro-Wilk Normal Distribution Test. When the distribution was normal, parametric tests, Student's t test and one-way ANOVA, were used. When the distribution was not normal, non-parametric tests, Mann–Whitney U test, and Kruskal–Wallis testwere used.

Results:

It was found that the standard mode of LCU produced lower amounts of TEGDMA, Bis-GMA, and UDMA in both composite materials. In addition, when the layer thickness increased, TEGDMA, Bis-GMA, and UDMA releases increased, too.

Conclusions:

This study revealed that the amount of residual monomers released from bulk-fill composites was affected by layer thickness and polymerization time.
Evaluation of partial pulpotomy treatment in cariously exposed immature permanent molars
Authors: Uyar D Sakaryalı , Alaçam A
Published: January 2022

Background and Aims:

This study aimed to assess the outcomes of partial pulpotomy treatments using different biocompatible materials which were Biodentine®, mineral trioxide aggregate (MTA), and calcium hydroxide (CH) in cariously exposed pulp tissue in immature permanent molars.

Materials and Methods:

Fifty-four teeth of 50 patients, which had cariously pulp exposures were randomly divided into Biodentine®, MTA, and CH groups for partial pulpotomy treatments and finally restored with stainless steel crowns at the same appointment. Clinical and radiographical success was evaluated by the absence of any clinical and radiographical signs and symptoms for 12 months. Also, Image J was used for the quantitative assessment of length developments for mesial and distal roots. P value of less than 0.05 was considered statistically significant.

Results:

Partial pulpotomy treatments showed high overall success rate (87%). On the other hand, Biodentine and MTA showed higher success rates compared to CH without any statistical significance (P = 0.09). Besides, mesial and distal root lengths displayed a continuous and significant increase in each group at sixth month follow-up (P = 0.01; P = 0.03).

Conclusions:

Favorable results demonstrated that Biodentine, MTA, and CH might be recommended as suitable agents for partial pulpotomy treatment in cariously exposed immature molars with clinical diagnosis of normal pulp or reversible pulpitis.
The impact of allergic rhinitis on symptoms, and quality of life using the new criterion of ARIA severity classification
Authors: Valero Antonio , Munoz-Cano Rosa , Sastre Joaquin , Navarro Ana M. , Marti-Guadano Enrique , Davila Ignacio , del Cuvillo Alfonso , Colas Carlos , Antepara Ignacio , Izquierdo Inaki , Mullol Joaquim
Published: January 2022

Introduction: Allergic rhinitis (AR) is a common disease with major socieconomic burden and a significant impact on quality of life. Objective: The objective of the study was to assess the impact of AR severity, using the modified ARIA (m-ARIA) severity criterion in order to discriminate among moderate and severe AR, in symptoms and quality of life assessed with the questionnaire ESPRINT-15. Methods: The specific quality of life questionnaire (ESPRINT-15) was applied in over thousand untreated RA patients. Severity was evaluated by the m-ARIA classification, which categorizes AR as mild, moderate, and severe. Nasal symptoms were evaluated by using categorized (none, low, middle, and high) Total Four Symptom Score (T4SS). Results: Using the m-ARIA severity classification, significant differences in quality of life, both global score and specific domains, and categorized T4SS were found among the AR severity groups. Conclusion: Modified ARIA severity classification in mild, moderate, and severe allergic rhinitis clearly discriminates the impact of AR in all domains of quality of life and categorized symptom`s score.
Unsettled Issues in Remote Operation for On-road Driving Automation
Authors:   Silicon Valley Mobility, Beiker Sven
Published: January 2022

On-road vehicles equipped with driving automation features—where a human might not be needed for operation on-board—are entering the mainstream public space. However, questions like “How safe is safe enough?” and “What to do if the system fails?” persist. This is where remote operation comes in, which is an additional layer to the automated driving system where a human remotely assists the so-called “driverless” vehicle in certain situations. Such remote-operation solutions introduce additional challenges and potential risks as the entire vehicle-network-human now needs to work together safely, effectively, and practically. Unsettled Issues in Remote Operation for On-road Driving Automation highlights technical questions (e.g., network latency, bandwidth, cyber security) and human aspects (e.g., workload, attentiveness, situational awareness) of remote operation and introduces evolving solutions. The report also discusses standards development and regulations—both of which are needed to provide frameworks for the deployment of driving automation with remote operation.
Unsettled Issues Concerning Automated Driving Services in the Smart City Infrastructure
Authors: Lambermont Serge , De Boer Niels ,   Nanyang Technological University
Published: January 2022

Information and communication technology is fundamentally changing the way we live and operate in cities, such as instant access to events, transportation, bookings, payments, and other services. At the same time, three “megatrends” in the automotive industry—self-driving, electrification, and advanced manufacturing technology—are enabling the design of innovative, application-specific vehicles that capitalize on city connectivity. Applications could countless; however, they also need to be safe and securely integrated into a city’s physical and digital infrastructure, and into the overall urban ecosystem. Unsettled Issues Concerning Automated Driving Services in the Smart City Infrastructure examines the current state of the industry, the developments in automated driving and robotics, and how these new urban, self-driving city applications are different. It also analyzes higher level challenges for urban applications. Ultimately, this report includes several options for sharing lessons learned among different cities and their stakeholders.
A Simulation and Experimental Study on Identification of an Electromechanical System
Authors: Kara Tolgay , Abokoos Sawsan
Published: January 2022

The current applications in electromechanical energy conversion demand highly accurate speed and position control. For this purpose, a better understanding of the motion characteristics and dynamic behavior of electromechanical systems including nonlinear effects is needed. In this paper, a suitable model of Permanent Magnet Direct Current (PMDC) motor rotating in two directions is developed for identification purposes. Model is parameterized and identified via simulation and using real experimental data. Linear and nonlinear models for the system are built for identification, and the effective nonlinearities in the system, which are Coulomb friction and dead zone, are integrated into the nonlinear model. A Weiner- Hammerstein nonlinear system description is used for identification of the model. MATLAB is selected as the investigating tool, and a simulation model is used to observe the error between the simulated and estimated outputs. Identification of the linear and nonlinear system models using experimental data is performed using the least squares (LS) and recursive least squares (RLS) methods. Performance of the model and identification method with the real time experiments are presented numerically and graphically, revealing the advantages of the proposed nonlinear identification approach.
Pedagogical Technologies for Competent Training of Teachers in Ukrainian Professional Education
Authors: Kulyk Yevhen , Kravchenko Liubov , Blyzniuk Mykola , Chystiakova Liudmyla , Orlova Nataliia , Bukhun Andrii
Published: January 2022

In recent decades, technological advances have revolutionized all areas of society, including the teaching resources and methodologies used in education. The relevance of pedagogical technologies in vocational education cannot be overemphasized, since technologies are constantly changing in today's environment, thus creating new challenges for modern education in globalization. The research aims are to establish patterns for promoting the implementation of pedagogical technologies in educational institutions for providing quality competent training of specialists in professional education. Research methods: comparative analysis; survey; systematization, generalization. As a result of the survey was established that pedagogical technologies positively influence the provision of competent training of specialists in Ukrainian professional education (89.7%), a smaller number of students (7.5%) were not sure about the quality of competent training of specialists in Ukrainian professional education with modern pedagogical technologies. It was determined that the students of educational institutions are most familiar with such pedagogical technologies as mobile learning (100%), e-learning (98%), independent learning (90%), virtual classroom (85%), and massive open online courses (MOOC) (71%). The study found that teachers need to improve digital competency from technologies such as Gamification and Next Generation Digital Learning Environment (NGDLE). Based on statistical data, it was found that the need for competent specialists in vocational education in the labor market is increasing every year, while those willing to study at vocational education institutions are decreasing every year. According to the negative trends, it has been determined that vocational education institutions should improve the educational process to increase the number of future competent specialists for the labor market.
Socio-legal representation of freedom of conscience
Authors:   Lviv university of business and law, Novikov Vitalii , Vicen Vlastimil , Semchuk Yurii
Published: January 2022

Freedom of conscience is the crucial goal we need to achieve for a sustainable future. The article examines the problems of freedom of conscience in various spheres of public relations. We have considered multiple aspects of this phenomenon: legal, economic, ethical, philosophical, epistemological, social. We paid special attention to the legal aspect of freedom of conscience. Due to this, we analyzed the existing legal guarantees of believers, non-believers and atheists, to determine the prospects for their further development. We have drawn attention to the fact that reducing the problems of freedom of conscience only to the legal aspect leads to the substitution of the worldview principles of a democratic society and to ideologizing. We have analyzed the different views of scholars on freedom of conscience as ethical, moral and personal categories. Based on a comprehensive socio-legal analysis of freedom of conscience, we concluded that the most important aspects of freedom of conscience are social, philosophical and legal. Finally, we argue that freedom of conscience is the basis for sustainable development in meaning of the 10th and 16th SDGs.
The testosterone barrier in sport
Authors: Sánchez García Raúl
Published: January 2022

World Athletics (formerly known as IAAF) has recently published the eligibility regulations for female classification that apply to running events from 400 meters up to the mile. The regulations have prevented some elite women athletes with DSD (Difference of Sexual Development) to compete or have made some of them to change their preferred running event in the 2020 Tokyo Olympics. According to World Athletics, female hyperandrogenism (a biological anomaly that naturally produces a high level of testosterone) must be in some way “compensated” to respect the fair play of the competition. Nonetheless, such argument rests upon a problematic assumption: hyperandrogenic women are not “natural” women —at least when it comes to compete in sports— so their “not-normal” condition must be fixed to meet the standards. Norbert Elias’s process-sociology helps to place the case of hyperandrogenic sportswomen within a broader context of power relations. In this fashion, we see that the case becomes problematic because these women athletes are perceived as a threat/disruption of one of the vertebral categories of sport: sex/gender. The testosterone barrier is to sex/gender what the colour barrier was to race in sports: a disciplinary strategy to maintain what is considered the “natural” sports categories of a certain era.