bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal Deformation Behavior of a New Metastable Beta Titanium Alloy
Authors: Li Jing , Wang Xin Nan , Zhu Zhi Shou
Published: June 2021

The thermal deformation behavior of a new metastable beta titanium alloy composed of Ti-Al-Mo-V-Nb-Cr was studied under different experimental conditions of varying temperatures (760°C~ 970°C) and strain rates (0.001s−1, 0.01s−1, 0.1s−1, 1s−1 and 10s−1) up to deformation amount of 60%. The hot compression experiments were completed on a Gleeble-3500 thermal analogue. The experimental results showed that the true stress of the Ti-Al-Mo-V-Nb-Cr titanium alloy decreased with increasing the temperature and decreasing the strain rate, the stress peaks and the steady-state stress values were higher with the decreasing of temperature at the same strain rate. The calculated values of the deformation activation energy were 187.87 kJ/mol in the two-phase region and 165.17kJ/mol in beta single-phase region. The corresponding constitutive equation was determined by the multiple linear regression calculation on the hot compression experimental data, on the base of Arrhenius equations.
Microstructure and Mechanical Properties of ER70-Ti Steel for Gas Shielded Welding Wire
Authors: Wang Xin Wei , Song Ren Bo , Pei Zhong Zheng , Chen Xing Han
Published: June 2021

In this paper, ER70-Ti welding wire steel produced by an enterprise was used as the test material. The final rolling temperature was set at 960 °C, 930 °C and 900 °C, and the spinning temperature was set at 880 °C, 860 °C and 840 °C. The results showed that the microhardness of the steel decreased from 303HV to 248HV and from 317HV to 276HV as the spinning temperature decreased from 880 °C to 840 °C. The microstructure and mechanical properties of the wires with the diameters of 5.5mm, 4mm, 2.5mm, 1.4 mm and 1.2mm were examined. It was observed that the microstructure of each sample had bainite and ferrite dual phase structure. With the decrease of wire diameter, the strength gradually increased and the ductility decreased. The experimental results show that the existence of bainite structure in the welding wire is the main reason for the high strength of the welding wire and easy fracture in drawing. Based on this, the final rolling temperature of 900 °C and the spinning temperature of 840 °C should be adopted in the production of ER70-Ti welding wire steel.
Experimental Study of Steel Reinforcement Repair Sleeve on X80 Pipe with Interlayer Defect
Authors: Wang Lin , Gao Jin , Wu Ming Chang , Yu Zhi , Ma Qiang
Published: June 2021

This paper introduces characteristics of common repairment method for oil and gas transmission pipeline, especially for steel reinforcement repair sleeve. In this research, an X80 pipe with interlayer defects repaired by steel reinforcement repair sleeve was studied. In order to investigate the repair effect of steel reinforcement repair sleeve for interlayer defects, a hydraulic blasting test and metallographic analysis for repaired pipeline were performed. The result shows that interlayer defect influences the pressure capacity of pipe to a certain degree, however, steel reinforcement repair sleeve could provide an acceptable strengthening to the repaired section.
Effect of Spray Distance on the Microstructure and High Temperature Oxidation Resistance of Plasma Spray-Physical Vapor Deposition 7YSZ Thermal Barrier Coating
Authors: Chen Wen Long , Liu Min , Xiao Xiao Ling , Zhang Xin
Published: June 2021

In order to study the effect of spray distance on the structure and high temperature oxidation resistance of feather-columnar thermal barrier coatings, the feather-columnar ZrO2-7wt. % Y2O3 (7YSZ) thermal barrier coatings were prepared at spray distances of 650 mm, 950 mm, 1100 mm, 1250 mm, and 1400 mm by plasma spray-physical vapor deposition (PS-PVD) technology. The surface roughness, micro morphology, and porosity of the sprayed 7YSZ coating were analyzed by 3D surface profiler, SEM, XRD, etc., and the impedance spectrum characteristics of the 7YSZ coating were characterized by electrochemical alternating current (AC) impedance technology. In addition, the high temperature oxidation resistance test of 7YSZ coating under different spray distances was carried out at a temperature of 1000 °C to study the influence of spray distance on the high temperature oxidation resistance of 7YSZ coating. The research results show that the surface roughness and porosity of feather-columnar 7YSZ coating increased sequentially with the increase of spray distance. At the same time, The YSZ grain boundary resistance value increased exponentially as the porosity of the coating increases. Where the spray distance was in the range of 650 mm and 1250 mm, the high temperature oxidation rate constant of the coating increased with the spray distance. However, the spray distance was greater than 1250 mm, and the spray distance had no significant effect on the high temperature oxidation resistance of the coating.
Corrosion Behavior and Mechanism of Oil Casing Steel in CO2 Salt Solution
Authors: Fang Xiao Jun , Liu Li , Yang Zhi Gang , Zhang Yong Qiang
Published: June 2021

The influence of temperature, flow rate, PH value, and oxygen content on the corrosion law in the carbon dioxide salt solution of J55 oil casing was investigated by the corrosion weight loss method. The results showed that with the increase of temperature, the corrosion rate of J55 steel first increased and then decreased and the corrosion rate reached the maximum at 100°C. The corrosion rate was closely related to the formation of corrosion products. The increase of the flow rate speeded up the transfer rate of the corrosive medium to the metal surface and hindered the formation of FeCO3 on the metal surface. The corrosion rate was significantly higher than the corrosion rate under static conditions, and as the flow rate increased, the corrosion rate of J55 steel increased accordingly. The increase of the pH value gradually reduced the concentration of hydrogen ions, and cathodic reaction of hydrogen ion depolarization during metal corrosion process was inhibited, and the tendency to form an oxidizing protective film on the surface of carbon steel increased, thereby reducing the corrosion rate of metals. With the increase of oxygen content, there were both hydrogen evolution reaction of CO2 and oxygen absorption reaction caused by O2 in the cathode process. The corrosion rate of J55 steel gradually increased, and at the same oxygen content, the higher the carbon dioxide content, the greater the corrosion rate is.
Study on the Oxidation Behavior of LPPS MCrAlY Coatings at High Temperature: Part II Coating Microstructure Development
Authors: Yuan Kang , Zheng Zhao Ran
Published: June 2021

MCrAlY can be used as bond coats for thermal barrier coatings (TBCs) with good ductility and excellent resistance against high temperature oxidation and hot corrosion. The behavior of the microstructure development in the MCrAlY coatings plays a key role on the oxidation resistance. In this paper, the microstructure in the coatings oxidized at 750~1100 °C was analyzed. The formation of the phases and their fraction were studied by comparing thermodynamic simulation results with the experimental observations. At higher temperatures (>1000 °C) β-to-γ’-to-γ phase transformation took place while at lower temperatures (<1000 °C) β phase would transfer to γ directly. The results show that the simulation can semi-quantitatively predict the microstructure formed in the coating.
Preparation and Performance Evaluation of a Novel Bactericide for Sulfate Reducing Bacteria
Authors: Fang Xiao Jun , Liu Li , Yang Zhi Gang , Zhang Yong Qiang
Published: June 2021

The sulfate reducing bacteria (SRB) bactericide was synthesized using KNO3, isothiazolinone, quaternary ammonium salt, and additives as main components, and the optimal ratio and critical concentration of the bactericide were determined. Weight loss method, potentiodynamic polarization curve, compatibility study were used to investigate the changes of corrosion rate and corrosion current density and compatibility after adding the bactericide. The results showed that the optimal formula ratio of the bactericide was: KNO3: isothiazolinone: quaternary ammonium salt: additive is 20:1:2:3, and the critical concentration of the bactericide was 50 mg/L. The addition of bactericides reduced the corrosion rate of pipes by 67% to 88%, and the electrochemical corrosion current density of pipes was significantly reduced, indicating that the presence of bactericides under the given media conditions significantly slowed down the corrosion process of metals. The bactericide was used in conjunction with commonly used oilfield chemicals such as corrosion inhibitors, scale inhibitors, flocculants, without obvious changes in appearance, no reduction in efficacy. Therefore, it may be concluded that the bactericide has good compatibility.
Phase Field Simulation on the Surface Morphology of Cu/Ti Nano Thin Film
Authors: Wu Ping Ping , Xing Bing Rui
Published: June 2021

Cu/Ti binary thin film system has many applications for micro-/nano- electro mechanical systems (MEMS/NEMS), micro-electronics and optoelectronics. In nanoscale, the quality and many physical properties of nano thin films are strongly depended on its surface morphology. In the present paper the development of surface morphology of double layered Cu/Ti thin film heterostructure with different composition and thickness has been studied by using the phase field method. The developed method is based on solving Cahn-Hilliard equations of multi-order parameters with considering the interfacial energy and elastic energy. The simulation results show that the thickness of Ti layer and Cu layer in the double-layer thin film structure can affect the surface roughness. For the heterostructures with the Cu layer thickness was fixed at 20 nm, the surface roughness was found to vary from 0.608 nm to 0.712 nm, when the Ti layer thickness increased from 10 nm to 30 nm. The calculated surface morphology and roughness was similar to the experimentally measured values. It is believed that this simulation method is useful in designing multi-layered thin film structure for practical applications.
Morphology of Dispersoids in an Annealed Al-Mg Alloys
Authors: Xiao Xiao Ling , Liu Hong Wei , Chen Wen Long , Lin Yi Ming
Published: June 2021

Morphology of dispersoids in an annealed Al-Mg alloy were investigated using TEM. Five kinds of dispersoids with different structures and morphologies were observed in an annealed Al-Mg alloy. The 1st, or spherical-like one is monoclinic structured θ-Al45(Mn,Cr)7 phase with twin and orientation domain. The 2nd or plate-shaped one is η-Al5(Mn,Cr) phase with monoclinic or pesuo-tetragonal structure. The 3rd or prismatic-like one is a new hexagonal structured Al6.4Mn phase with a unit cell of a=1.72nm, c=1.27nm, and γ=120°, and the 4th or big rod-shaped one is orthorhombic structured Al6(Mn,Fe) phase which is often reported. The 5th one is E-Al18Mg3(Mn–Cr)2 phase with twin or triple twin observed occasionally in Al-Mg annealed alloy. The first two of dispersoids are in majority, followed by the middle two and a small number of the fifth. Formation mechanisms of these particles in Al-Mg alloy are discussed according to phase diagram and possible formation of the twins in the particles are described based on minimum energy.
Effect of Annealing Temperature on the Soft Magnetic Properties of Fe70.43Nb10.77Si15.77Cu2.34B0.69 Amorphous Aanostrips at 20K, 300K
Authors: Lei Sheng , Li Shuai , Sun Jun , Zhu Ji Xiang , Liu Ya Feng , Xu Hai Li
Published: June 2021

Since Fe-based amorphous alloys are widely used in magnetic separators, sensors and other fields, it is of practical significance to carry out research on amorphous strips used in this field.The effects of annealing temperature on the soft magnetic properties of Fe70.43Nb10.77Si15.77Cu2.34B0.69 amorphous nanostrips with 25 μm and 28 μm thickness prepared by the single roll cold method were investigated at 20 and 300K.Five specimens were annealed at472.12K, 672.12K, 772.12K, 822.12Kand 872.12K, respectively, and their microstructure and magnetic properties were tested viametallographic microscopy, X-ray diffraction, and vibrating specimen magnetometer. At cryogenic temperatureof 20K, specimens annealed at 672,12K exhibited the best magnetic properties, including the coercive forceof8.1265A/m, saturation magnetic induction intensity of1.4351T,and its residual value of 0.2462T. The comparative analysis of experimental results obtained strongly indicates that the soft magnetic properties of the amorphous alloy are significantly improved by the particular annealing treatment.
Effect of Boronizing Treatment on the Conductivity of a High-Conductivity and Heat-Resisting Al-Zr Alloy Conductor Material
Authors: Zheng Zhi Kai , Xiao Xiang , Wu Hao , Li Hong Ying , Zhao Pi Zhi
Published: June 2021

The effect of boronizing treatment on the conductivity of a high-conductivity and heat-resistant Al-Zr alloy conductor material was studied. The results showed that the conductivity of industrial pure Al containing transition element (Ti, V, Cr, Mn)>0.01 wt % (mass fraction, the same below) was improved to a certain extent by using boronizing treatment to remove transition metal elements through the formation of borides. Using the boronizing treatment, B can react with transition elements to form blocky (Ti, V, Fe)B2and flocculent (Ti, V, Fe, Zr)B2. The boronizing treatment makes Ti and V out of the solid solution state, form borides and finally deposit to the bottom of the furnace, thus significantly improving the conductivity of the ingot. In addition, Cr and Mn were not found in the borides at the bottom of the furnace. However, for the high-conductivity and heat-resisting Al-Zr alloy conductor material, B will have poison effects on Zr during boronizing treatment, thus reducing the heat-resistance of the alloy. Therefore, in the preparation process of high-conductivity and heat-resistant Al-Zr alloy conductor material, the converter process should be added after boronizing treatment to ensure that the Al-Zr alloy conductor material has good heat-resistance and conductivity at the same time.
Long-Term Duration of Composite Repair Systems for Pipeline Defects
Authors: Ming Lian Xun , Yao Deng Zun , Chen Bin , Teng Zhen Heng , Wang Lin
Published: June 2021

Composite repair systems of buried pipeline will be affected by moisture and other factors due to anti-corrosion and construction problems. These environmental factors will reduce the service life of the composite system. In this paper, the performance of composite and interface between composite and steel under the action of water were studied. It was found that the formation of micro-cracks on the surface of composite materials and the hydrolysis of epoxy resin were the important reasons for the Performance degradation. Moreover, the aging properties of composite materials and their interfaces under water immersion were analyzed by residual strength theory, and the life prediction equation of composite materials and interfaces were obtained, which can be useful to the field application of composite repair systems.
Emission Characteristics of VOCs during Asphalt Pavement Construction
Authors: Ma Yin Huai , Guo Li , Wu Shao Peng , Li Na , Xie Jun
Published: June 2021

As the important part of expressway, the construction technology of asphalt pavement will contribute to the production of greenhouse gases and other volatile organic compounds (VOCs), which has a significant impact on the environment. In order to further analyze the composition, distribution and release of VOCs during asphalt pavement construction, the VOCs emission during paving and rolling were measured through field investigation and sampling. The results show that there are approximately 100 kinds of VOCs substances detected due to the complex organic component of asphalt binder, which is a critical factor to influence the VOCs emission during asphalt pavement construction. During the paving process, the largest VOCs release is 1015.05 ug/m3. With the increase of rolling times, the pavement temperature gradually decrease, and the VOCs emission drops to 266.73 ug/m3. The content of the 10 kinds of substances with the highest concentration accounts for more than 50% of the total VOCs content, in which the proportion of aliphatic hydrocarbons (ALH) and oxygenated hydrocarbon (O-HYD) of the paving process are the highest, while the proportion of aromatic hydrocarbons (ARH) is dominated in the rolling process. The results are vulnerable to the external environment, especially at lower emission level. The relevant research results have certain guiding significance for the control and treatment of harmful gas emission in the construction process of asphalt pavement.
4–20mA optical sensor at 300C using SiC and SOI integrated circuits
Authors: Chen Cheng-Po , Andarawis Emad
Published: June 2021

GE is reporting test results from a hybrid circuit using high temperature capable resistors, capacitors, silicon carbide devices and silicon-on-insulator integrated circuits. The sensing circuit converts photodiode current to an industrial standard 4 to 20 mA output using a two wire configuration. Input currents at levels from 0pA to 30nA is converted to 4 to 20 mA using a gain compression technique and tested from room temperature to 300°C. Further, we show the circuit operating at 300°C for more than 2000 hours without failure.
Upscaling of 500 °C Durable SiC JFET-R Integrated Circuits
Authors: Neudeck Philip G. , Spry David J. , Krasowski Michael J. , Chen Liangyu , Greer Lawrence C. , Chang Carl W. , Lukco Dorothy , Beheim Glenn M. , Prokop Norman F.
Published: June 2021

At HiTEC 2018, NASA Glenn Research Center reported the first demonstration of yearlong 500 °C operation of ceramic-packaged “Generation 10” ~200-transistor integrated circuits (ICs) based on two-level interconnect silicon carbide (4H-SiC) junction field effect transistors and resistors (JFET-R). This HiTEC 2021 submission updates on-going efforts at NASA Glenn spanning two subsequent prototype IC generations “11 and 12” to increase both complexity and durability of these ICs. Increased chip complexities of around 1000 transistors/chip for Gen. 11 and near 3000 transistors/chip for Gen. 12 are made possible by reductions in minimum layout feature sizes (including resistor width shrinkage from 6 μm to 2 μm) coupled with enlarged die size (from 3 × 3 mm to 5 × 5 mm). Gen. 11 ICs electrically tested to date include an 8-bit delta-sigma analog to digital converter (ADC) as well as upscaled random access memory (RAM) and nearly 1 kbit read only memory (ROM). However, Gen. 11 prototype ICs exhibited significantly lower yield and durability than Gen. 10 ICs. Development of revised processing is being investigated towards mitigating these issues in subsequent Gen. 12 fabrication run currently in progress.
Efficacy and Safety of Rituximab in Central Nervous System Demyelinating Disorders
Authors: Patil Varsha A. , Kamat Saurabh N. , Lalkaka Jamshed A. , Singhal Bhim
Published: June 2021

Background:

Rituximab, an anti-CD20 monoclonal antibody, has been used worldwide as an off-label therapy in patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD).

Objective:

The aim of the present study was to evaluate the efficacy and safety of rituximab in central nervous system demyelinating disorders in the Indian context.

Methods:

We conducted a retrospective analysis of patients with MS, NMOSD, and myelin oligodendrocyte glycoprotein antibody disease (MOGAD) who were treated with rituximab at a single tertiary care centre in Mumbai.

Results:

The study enrolled 102 patients (61 MS, 37 NMOSD and 4 MOGAD) from June 2008 to January 2020. Following rituximab therapy, 96.7% of MS, 67% of NMOSD, and 50% of MOGAD patients were free of relapses. The mean annualized relapse rate reduced from 2.17 to 0 for patients with relapsing remitting MS (RRMS), from 0.8 to 0 for secondary progressive MS (SPMS), from 2.5 to 0.14 for NMOSD, and from 3.43 to 1.04 for MOGAD. The median expanded disability status scale improved significantly in RRMS patients, worsened non-significantly in the SPMS group, and remained unchanged in NMOSD and MOGAD patients. On follow-up magnetic resonance imaging, there was a significant reduction in the number of MS patients developing new contrast enhancing lesions or new T2 lesions. Adverse events (infusion reactions or severe infections) occurred in 12 patients.

Conclusion:

Rituximab is effective and safe in Indian patients with MS and NMOSD.
Evaluation of Cardiovascular Functions during the Practice of Different Types of Yogic Breathing Techniques
Authors: Nivethitha L. , Mooventhan A. , Manjunath N. K.
Published: June 2021

Introduction:

Yoga is the science of right living practice to promote health. Many studies have documented the cardiovascular effects of various yogic breathing techniques (YBTs), comparing the cardiovascular changes before and after the practice. However, there is a lack of study reporting the cardiovascular changes during the practice of YBT.

Materials and Methods:

Twenty healthy individuals performed four different YBTs (Bhastrika, Bhramari, Kapalbhati, and Kumbhaka) in four different orders. Cardiovascular variables such as systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), stroke volume (SV), cardiac output (CO), pulse interval (PI), and total peripheral resistant (TPR) were assessed using a continuous noninvasive blood pressure monitoring system, before, during, and immediately after each YBT. Data were analyzed using repeated measures analysis of variance followed by post hoc analysis with Bonferroni adjustment for multiple comparisons using Statistical Package for the Social Sciences, Version 16.0.

Results:

Results of this study showed a significant increase in DBP, MAP, HR, and CO along with a reduction in PI during Bhastrika; a significant increase in DBP, MAP, HR, and TPR with a reduction in SV, CO, and PI during Bhramari pranayama; a significant increase in SBP, DBP, MAP, HR, and CO with a reduction in PI during Kapalbhati; and a significant increase in SBP, DBP, MAP, and TPR with a reduction in SV and CO during Kumbhaka practice.

Conclusion:

In healthy individuals, cardiovascular changes during the practice of Bhastrika and Kapalbhati are more or less similar to each other and are different from those of Bhramari and Kumbhaka in most of the variables.
Peripartum Cardiomyopathy in Indian Population
Authors: Agarwal Rakesh , Baid Rashmi , Sinha Dhurjati Prasad
Published: June 2021

Introduction:

Peripartum cardiomyopathy (PPCM) refers to heart failure of unknown etiology in later gestation or early postpartum period. Data regarding its incidence, clinical features, risk factors, and outcomes in the Indian population are scarce.

Materials and Methods:

We performed a pooled analysis of seven Indian studies on PPCM, including 221 patients to study PPCM.

Results:

The incidence of PPCM in the Indian population was 1 in 1340 live births. Indian women developed PPCM at a mean age of 27 years and most commonly in the postpartum period (60% cases). Hypertensive disorders and anemia were associated with PPCM in nearly half the number of patients. Maternal mortality was 11.7% and fetal mortality 14.2%.

Conclusion:

Our study provides data on PPCM in the Indian population. Larger studies with higher number of patients are needed to study PPCM in detail in the Indian subset.
Role of N-terminal pro-B-type Natriuretic Peptide in Predicting Mortality in Heart Failure
Authors: Jena Kamal Kant , Vishwanathan N , Manohar G , Singh Prashant Kumar , Chakraborty Nayan
Published: June 2021

Background:

N-terminal pro-B-type natriuretic peptide (NT-proBNP) improves emergency room diagnosis and is a prognostic marker of acutely decompensated heart failure (HF) after hospitalization. We tried to assess the prognosis in heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF) using the biomarker.

Methods:

Patients were categorized into HFpEF (left ventricular ejection fraction [LVEF] ≥50%) (n = 102), HF with midrange EF (LVEF of 40%–49%) (n = 106), and HFrEF (LVEF ≤40%) (n = 112) as per the ESC classification of HF subtypes. Prognosis by absolute and percentage change in NT-proBNP at admission and at the 10th day of treatment was found in 3-month follow-up. Mortality after discharge was also assessed.

Results:

Among all HF groups, a reduction of NT-proBNP <20% at 10 days predicted mortality, hazard ratio (HR) – 14.9 (95% confidence interval [CI]: 3.8–57.9), P = 0.0001. The risk of mortality in HF patients with NT-proBNP reduction of <20% in 10 days was 14.9 times higher in 3-month follow-up. NT-proBNP more than 12,000 pg/mL at admission had a mortality risk of 23.3% in the HFrEF group, HR – 23.45 (95% CI: 2.9–189.4), P = 0.003. NT-proBNP on the 10th day, more than 9000 pg/mL, had a mortality risk of 21.4% in the HFrEF group, HR – 23.3 (95% CI: 4.9–110.5), P = 0.001.

Conclusion:

NT-proBNP proved to be a superior modality in finding out prognosis in HF. Patients with the HFrEF group had a higher mortality in our study. Comorbidities play an important role in affecting the prognosis in patients with HFpEF with lower NT-proBNP.
Hemodynamic changes in pediatric dental patients using 2% lignocaine, buffered lignocaine, and 4% articaine in pediatric dental procedures
Authors: Khatri Amit , Afsal M. M. , Kalra Namita , Tyagi Rishi , Kulood M. Khadeeja
Published: June 2021

Background:

The purpose of this study was to compare the hemodynamic changes (blood pressure, heart rate and oxygen saturation) when using three different local anesthetic agents such 2% Lignocaine with 1:200,000 epinephrine, Buffered Lignocaine and 4% Articaine with 1:200,000 epinephrine with inferior alveolar nerve block in pediatric dental patients.

Methods:

A double blind crossover study was designed where in 48; 5-10 year old patients received three sections of inferior alveolar nerve block injections in three appointments which scheduled one week apart. Blood pressure, heart rate and oxygen saturation was measured before and after administration.

Results:

When applying three factors ANOVA, no statistically significant difference was found between Lignocaine and Buffered Lignocaine, Buffered Lignocaine and Articaine in all the three parameters(P > 0.05).

Conclusion:

This findings in hemodynamic changes from this study reveals that all the three anesthetic agents are safe in children aged 5-10 years.
Autologous platelet concentrates in periodontal regenerative therapy
Authors: Dufare Dhiraj B.
Published: June 2021

Autologous platelet concentrates (platelet-rich plasma and platelet-rich fibrin) enriched with various growth factors play an important role in periodontal regeneration. This review includes biological principle, efficacy, and effectiveness of autologous platelet concentrates. Based on the result obtained from the systematic review and meta-analysis it can be concluded that complimentary effects of autologous platelet concentrates may be used as lucrative adjunct to regenerative periodontal therapy. However, postoperative plaque control is one of the key factors influencing periodontal healing following regenerative periodontal therapy.
Temporomandibular joint ankylosis pattern, causes, and management among pediatric patient attending a tertiary hospital in Bangladesh
Authors: Shakilur Rahman A. F. M. , Haider Ismat Ara
Published: June 2021

Background:

Temporomandibular joint (TMJ) ankylosis is a pathological condition where mandibular condyle fused the glenoid fossa of the temporal bone. It causes distressing and disabling conditions to the patient. The purpose of our study is to determine the frequency of pediatric TMJ ankylosis attending at Oral and Maxillofacial Surgery Department, Dhaka Dental College and Hospital, Bangladesh.

Methodology:

This was a retrospective, cross-sectional study for 18 patients (9 male and 9 female) aged up to 18 years old. Data assembled from the patient's surgical records reviewed from January 2016 to December 2018.

Results:

Females and males were affected equally, the most affected age group was 7–12 as well as 13–18 years old (n = 7, 38.89%), bilateral ankylosis (n = 11, 61.11%) was more common than unilateral (n = 7, 38.89). Type III (34.48%) ankylosis (Sawhney's classification) was found to be the most frequent type. Trauma (n = 11, 61.10%) was the major etiologic factor for pediatric TMJ ankylosis. All patients were managed by surgical intervention. Gap arthroplasty (n = 9; 50.0%) was the most preferable treatment method followed by interpositional arthroplasty (n = 7, 38.89%) and condylectomy (n = 2, 11.11%).

Conclusion:

The majority of the patient was affected by trauma. Most of the patients came with Type III ankylosis with having facial deformities. Absolute and proper management regarding mandibular condylar fracture and infection (middle ear) must be required to prevent TMJ ankylosis. Surgical intervention is the only treatment option for managing TMJ ankylosis. Aggressive physiotherapy is mandatory to prevent reankylosis, thus ensuring the patient's quality of life.
Interleukin-10
Authors: Chang Chun-Ming , Lam Ho Yin Pekkle , Hsu Hao-Jen , Jiang Shinn-Jong
Published: June 2021

Breast cancer (BC) is a frequently diagnosed cancer among women worldwide. Currently, BC can be divided into different subgroups according to the presence of the following hormone receptors: estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. Each of these subgroups has different treatment strategies. However, the presence of new metastatic lesions and patient deterioration suggest resistance to a given treatment. Various lines of evidence had shown that cytokines are one of the important mediators of tumor growth, invasion, metastasis, and treatment resistance. Interleukin-10 (IL-10) is an immunoregulatory cytokine, and acts as a poor prognostic marker in many cancers. The anti-inflammatory IL-10 blocks certain effects of inflammatory cytokines. It also antagonizes the co-stimulatory molecules on the antigen-presenting cells. Here, we review the current knowledge on the function and molecular mechanism of IL-10, and recent findings on how IL-10 contributes to the progression of BC.
Current advances of targeting epigenetic modifications in neuroendocrine prostate cancer
Authors: Cheng Wen-Chi , Wang Hung-Jung
Published: June 2021

Neuroendocrine prostate cancer (NEPC) is the most lethal malignancy of prostate cancer (PCa). Treatment with next-generation androgen receptor (AR) pathway inhibitors (ARPIs) has successfully extended patients' lifespan. However, with the emergence of drug resistance, PCa tumors increasingly adapt to potent ARPI therapies by transitioning to alternative cellular lineage. Such therapy-induced drug resistance is largely driven from the cellular plasticity of PCa cells to alter their phenotypes of AR independence for cell growth and survival. Some of the resistant PCa cells undergo cellular reprogramming to form neuroendocrine phenotypes. Recent evidences suggest that this cellular reprogramming or the lineage plasticity is driven by dysregulation of the epigenome and transcriptional networks. Aberrant DNA methylation and altered expression of epigenetic modifiers, such as enhancer of zeste-homolog 2, transcription factors, histone demethylases, are hallmarks of NEPC. In this review, we discuss the nature of the epigenetic and transcriptional landscapes of PCa cells which lose their AR independence and transition to the neuroendocrine lineage. We also discuss how oncogenic signaling and metabolic reprogramming fuel epigenetic and transcriptional alterations. In addition, the current state of epigenetic therapies for NEPC is addressed.
French as the Teaching Language of Life and Earth Sciences in Moroccan School: what’s the Teachers’ Opinion?
Authors: Ifqiren Sara , Selmaoui Sabah , Ait Yahia Fatima Ezahra , Agorram Boujemaa
Published: June 2021

The strategic vision for the recent reform in Morocco included the diversification of teaching languages by teaching scientific subjects in French. This starts in pilot’s class teaching scientific subjects in the French language. In this context, the language for teaching Life and Earth Sciences (LES) was changed from Arabic to French. This linguistic change in teaching LES aims to make the learner able to communicate in French in addition to Arabic, and to put an end to the linguistic problem that currently exists when entering universities, that teach these subjects in the French language. In this survey we interested to teachers’ opinions in order to get acquainted with their opinions in teaching Life and Earth Sciences in French for the middle school, and collecting suggestions and solutions to overcome the problem observed in classrooms. We used a questionnaire as an investigative tool for data collection distributed to life and earth sciences’ teachers of middle school. The findings of this research shows that teaching this subject in French forms an obstacle to academic achievement, and classroom interaction, whether in the rural or urban areas. This is due to reasons related to the poor language level of students, the absence of teacher continuous training in teaching the subject in French, and the weakness of the means adopted to make this change in the language of instruction. Among the solutions that have been proposed and used to overcome this educational phenomenon is the preparation of a support plan that includes a program consisting of activities targeting the communicative aspect for learners in French, as well as other activities aimed at providing the learner with skills such as analysis, description, observation and conclusion, while translating scientific words from French into Arabic.
Digital Twins for Education and Study of Engineering Sciences
Authors: Zacher Serge
Published: June 2021

Generally a digital twin is a software-model as a prototype for some product, ordered by a customer. It shell be used on all stages of industrial production of this ordered product, compering the actual state with the model und correcting the differences. A “virtual world” will be created from the “real word” and both “worlds” communicate with each other during production. At the educational institutions of engineering like universities, trainings centres or schools the digital twins are software-models of industrial plants, which are simulated and visualized similar to its industrial originals and synchronized with them. The presented paper shows steps of design of digital twins upon some examples of the master degree program at the University of Applied Sciences Darmstadt. It will be described why and how it is possible to use the digital twins. The ways from an original device to its model will be drawn. The different stages of the development of software-models, which are equipped with different levels of source code, will be shown. The actual trends to include the hardware into a software-model, so called hardware-in-the-loop and rapid control prototyping, will be described. Finally the advantages and disadvantages of digital twins for engineering study including the economic considerations will be discussed.
Approximation Procedure for Determining Oscillation Period of Frame Structure
Authors: Tresnjo Faris , Muratović Majudin
Published: June 2021

Dynamic analysis can be used to find dynamic displacements, time history, and the frequency content of the load. One analysis technique for calculating the linear response of structures to dynamic loading is a modal analysis. In modal analysis, we decompose the response of the structure into several vibration modes. A mode is defined by its frequency and shape. Structural engineers call the mode with the shortest frequency (the longest period) the fundamental mode. Holzer and Stodola's approximate methods for determining the forms and periods of oscillation for frame structures are presented in the paper. An approximation method, based on approximate relative stiffnesses of the storeys and the ground floor, is analyzed and proposed. The results obtained by the proposed approximate procedure do not greatly deviate from those obtained by more accurate calculations. It is therefore emphasized that the method can be used both in practice and for checking computer-based analysis of complex systems. At the end of the paper was given a comparison of the results obtained by approximate methods and some engineering software.
Agenda-Setting na educação
Authors: Silva Thiago José da , Moraes Silvia Piedade de
Published: June 2021

Esta pesquisa teve como objetivos desvelar os tipos de violações dos Direitos Humanos tratados pela mídia, sua abordagem e como  essas violências são pautadas dentro da educação escolar e conhecer a linguagem na qual são noticiadas. Trata-se de estudo qualitativo e documental que visa conhecer a agenda midiática sobre o assunto para compreender sua pauta, linguagem e enfoque.  Foram coletados 43 notícias de abril de janeiro de 2019 a janeiro de 2020 em três mídias de abrangência nacional - site UOL, Jornal O Globo (on-line) e Revista Veja (on-line) organizados em sete categorias para análise de conteúdo. Ao longo da pesquisa procurou-se responder quais os tipos de violação dos Direitos Humanos ocorrem em relação à educação escolar, como são noticiados e como essa ferramenta pode ser aplicada na formação do saber em sala de aula. Concluiu-se que as contribuições dessa pesquisa estão ligadas em três pontos muito importantes, tais como: desvelar e caracterizar como a mídia pauta as violências expressadas nas escolas, como ela pode ser uma influência direta na formação de professores, alunos e toda a comunidade escolar acerca das violências, dar uma demonstração real através da verificabilidade dos fatos constatados pelas mídias e como essa ferramenta pode servir de subsídio para denunciar, educar e conscientizar sobre as demandas opressivas recorrentes nas escolas.
About new promising fi elds and ore occurrences of the southern slope of Greater Caucasus (Azerbaijan)
Authors: Ганбарова Э.Ф.
Published: June 2021

Статья посвящена перспективности новых выявленных рудопроявле-
ний азербайджанской части Большого Кавказа. Установлено, что как колчеданно-по-
лиметаллические, так и медно-пирротиновые и серно-колчеданные руды различных
месторождений и рудопроявлений занимают весьма различные стратиграфические
уровни разреза, начиная от тоара до верхнего аалена включительно. Весь этот воз-
растной интервал, по существу, состоит из чередующихся слоев глинистых сланцев
аргиллитов, песчаников и алевро-песчаников. Геолого-структурные позиции и резуль-
таты опробования позволяют отнести эти участки к перспективным и считать
их объектами дальнейшего изучения комплексом геолого-геохимических и геофизи-
ческих исследований и буровых работ. Приводится краткое описание наиболее инте-
ресных и более детально изученных проявлений рудных месторождений и проявлений.

The article is devoted to the prospects of new identifi ed ore occurrences in the
Azerbaijanian part of the Greater Caucasus. It is established that both pyrrhic-polymetallic and
copper-pyrrhotite and sulfur-pyrrhotite ores of various deposits and ore occurrences occupy
very different stratigraphic levels of the section, starting from the Toar to the upper Aalen
inclusive – and it is important to note that this entire age range essentially consists of alternating
layers of clay shales, mudstones, sandstones, and siltstones. The geological and structural
positions and the results of testing allow us to classify these areas as promising and consider
them objects of further study by a complex of geological, geochemical and geophysical studies
and drilling operations. A brief description of the most interesting and more thoroughly studied
manifestations of ore deposits and manifestations is given.
Possibilities of radiocarbon (14C) method for age determination of geological events in the Elbrus volcanic centre area
Authors: Гурбанов А.Г. , Газеев В.М. , Гурбанова О.А.
Published: June 2021

Радиоуглеродный метод (14С) позволяет датировать геологические события по детриту и
древним углям из погребенных почв, начиная с 40-50 тыс. лет тому назад и до сотен лет. Однако для его
широкого применения в пределах Эльбрусского вулканического центра (высота вулканической постройки 5
642 м), при датировании времени излияния отдельных лавовых потоков, имеются объективные ограничения.
Они заключаются в том, что начиная с отметки от 3 300 м и выше в горах Северного Кавказа отсутствует
травяно-кустарниковая растительность и почвенный слой с гумусом, и именно на этих высотах расположе-
на значительная часть голоценовых лавовых потоков и туфовых горизонтов Эльбруса, а с 3 700 м и выше
вулканическая постройка покрыта вековыми ледниками и снежниками. В результате проведенных исследо-
ваний для голоцена были установлены: частоты повторяемости извержений вулкана Эльбрус и землетря-
сений, проявившихся в Приэльбрусье. В итоге была выявлена важная закономерность, свидетельствующая
о том, что к концу голоцена частоты повторяемости извержений Эльбруса и землетрясений резко воз-
растают. Установлено совпадение времени проявления вулканической и сейсмической активности (причем
вторая проявлялась несколько раньше первой). При этом периоды вулканической и сейсмической активности
резко возрастают, а периоды покоя сокращаются. Эти данные имеют важное значение для оценки возмож-
ности возобновления вулканической и сейсмической активностей в пределах Приэльбрусья в геологическом
будущем.

Radiocarbon (14C) method makes possible to dating of geological events on detritus and older coals from
buried soil from 40-50 thousands years ago up to hundreds years. However, for its wide applica-tion within of Elbrus
volcanic centre (altitude of Elbrus volcano is 5642 m) for dating time of separate lava fl ows eruption, there are an objective
boundaries. They are implies that starting with altitude of 3300 m and higher in the Northern Caucasian mountains the
grass and handicraft and soil with humus are absent, and just on this altitude the most part of Holocene lava fl ows and tuff
horizons are located and with 3700 m and higher volcano is covered by glaciers and perpetual snow (fi rn). As a result of
carried out investigation for Holocene the density of recurrence of Elbrus volcano eruptions and earthquakes manifestation
in Elbrus volcanic area have been established.
As a sum the important relationship, testifi es that to the end of Holocene the density of recurrence of Elbrus eruptions and
earthquakes are sharply increase. Agreement in time between volcanic and seismic activity (but manifestation the second
one was some early then fi rst one). In so doing, periods of volcanic and seismic activity are sharply increase, but periods
of rest are shrink. This data have an important relationship for estimation possibility of restating of volcanic and seismic
activities in Elbrus volcanic area in geological future.
Refuerzo virtual como estrategia - enseñanza, “GOCONQR” para potenciar el aprendizaje extra clase en estudiantes secundários
Authors: Ortega Mauricio Xavier Prado , Córdova Rosman José Paucar , Segarra Anyeline Natalia González , Romero Héctor Ramiro Carvajal
Published: June 2021

El constante fortalecimiento en la educación evidenciado por la incorporación de herramientas informáticas desarrolladas para apoyar el aprendizaje de los estudiantes y la adaptación de estrategias fáciles de usar con las que los docentes promueven y promueven la difusión de contenidos digitales promueven el interés por abordar el tema. de refuerzos virtuales como instrumento extra de clase, utilizando dispositivos móviles y portátiles. El presente estudio presenta una metodología con enfoque mixto que centra su análisis en la investigación acción asociada al abordaje diagnóstico de modelos pedagógicos en instituciones educativas de nivel medio para promover el uso de la tecnología a aquellas con la intervención de estudiantes universitarios de la Carrera de Pedagogía. de Ciencias Experimentales de la UTMACH a través de prácticas preprofesionales a través de un proyecto integrador de conocimientos. Entre los problemas más relevantes se encuentra la falta de motivación y desinterés de los estudiantes por los contenidos impartidos por los profesores en las asignaturas de ciencias blandas en el aula. Se utilizaron instrumentos como encuestas dirigidas a estudiantes de secundaria en estudio. Una solución alternativa presentada como objetivo general mediante la aplicación de GoConqr como herramienta tecnológica virtual complementaria a las clases de los alumnos con la ayuda de sus profesores de segundo bachillerato de la Escuela Kléber Franco Cruz. Entre los resultados más relevantes del estudio realizado cuando se utilizó GoConqr, se experimentaron algunos beneficios de su aplicación, que permitieron evaluar conocimientos, motivar la interacción y despertar el interés por los contenidos digitales incorporados en las asignaturas, incentivando el nivel de los estudiantes. de aprendizaje. La investigación concluye que el refuerzo virtual de contenidos presentados digitalmente mediante dispositivos móviles puede ser una estrategia docente y un elemento de acompañamiento para que el alumno mejore su interés por el aprendizaje.
Sistema de orientación vocacional profesional en la construcción de proyectos de vida
Authors: Vera Kerly Leomar Toala , Cevallos Francisco Antonio Mawyin , Sardi Gustavo Adolfo Santana , Palma Pedro Alejandro Escobar
Published: June 2021

La siguiente investigación se basa en un sistema de orientación vocacional profesional en la construcción de proyectos de vida y para hablar sobre la orientación vocacional y profesional es indispensable adentrarse en el objeto de estudio y para esto se logra desarrollar un camino desde el inicio y todo el progreso de este campo, el concepto de orientación vocacional y profesional parte desde el momento en que el hombre en su necesidad de conformar la sociedad, se da cuenta y reconoce que de acuerdo al rol que desempeña cada individuo cumple un papel fundamental en la misma. La orientación vocacional profesional es un apoyo al proceso de la toma decisiones como parte de un proyecto de vida, en él, el individuo conoce sus capacidades, potencialidades, intereses y limitaciones o dificultades, así como sus posibilidades existentes en el medio que se desarrolla. El proceso de construcción de proyectos de vida requiere de un enfoque causal, donde es necesario el análisis individualizado, contextualizado y dinámico de cada persona. Este estudio es realizado bajo la técnica documental tipo bibliográfico el cual permitió una investigación  sobre las posibles necesidades de cada individuo para su adecuada estructuración y la elaboración de un sistema de orientación vocacional profesional con un enfoque individualizado, contextualizado del proceso, lo que conllevó al esclarecimiento de las metas futuras de cada persona y regular de manera efectiva sus conductas para el logro de las metas trazadas.
Strecker Synthesis of α-aminonitriles Facilitated by N-methyl Imidazolium Acetate
Authors: Madadi Elaheh
Published: June 2021

N-Methyl imidazolium acetate [HMIm]OAc was simply prepared through reaction of N-methyl imidazole with acetic acid and it was applied as a media and promoter for Strecker synthesis of α-aminonitriles. The three component reaction of a variety of structurally different aldehydes and amines with trimethylsilyl cyanide (TMSCN) in the presence of [HMIm]OAc were evaluated. Reaction of aromatic aldehydes and cinnamaldehyde with either aromatic and aliphatic amines provided the corresponding α-aminonitriles in high to excellent isolated yields after short period of time at room temperature.