bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of telomere silencing is accompanied by dysfunction of Polo kinase and centrosomes during Drosophila oogenesis and early development
Authors: Morgunova Valeriya , Kordyukova Maria , Mikhaleva Elena A. , Butenko Ivan , Pobeguts Olga V. , Kalmykova Alla
Published: October 2021

Telomeres are nucleoprotein complexes that protect the ends of eukaryotic linear chromosomes from degradation and fusions. Telomere dysfunction leads to cell growth arrest, oncogenesis, and premature aging. Telomeric RNAs have been found in all studied species; however, their functions and biogenesis are not clearly understood. We studied the mechanisms of development disorders observed upon overexpression of telomeric repeats in Drosophila. In somatic cells, overexpression of telomeric retrotransposon HeT-A is cytotoxic and leads to the accumulation of HeT-A Gag near centrosomes. We found that RNA and RNA-binding protein Gag encoded by the telomeric retrotransposon HeT-A interact with Polo and Cdk1 mitotic kinases, which are conserved regulators of centrosome biogenesis and cell cycle. The depletion of proteins Spindle E, Ccr4 or Ars2 resulting in HeT-A overexpression in the germline was accompanied by mislocalization of Polo as well as its abnormal stabilization during oogenesis and severe deregulation of centrosome biogenesis leading to maternal-effect embryonic lethality. These data suggest a mechanistic link between telomeric HeT-A ribonucleoproteins and cell cycle regulators that ensures the cell response to telomere dysfunction.
The effect of increasing indoor ventilation on artificially generated aerosol particle counts
Authors: Johri Ashwin
Published: October 2021

The COVID-19 global pandemic has caused millions of infections and deaths despite mitigation efforts that involve physical distancing, mask-wearing, avoiding indoor gatherings and increasing indoor ventilation. The purpose of this study was to compare ways to improve indoor ventilation and assess its effect on artificially generated aerosol counts. It was hypothesized that inbuilt kitchen vents would be more effective in reducing indoor aerosol counts than opening windows alone. A fixed amount of saline aerosol was dispersed in the experimental area using a nebulizer under constant temperature and a narrow range of humidity. A laser air quality monitor was used to record small particle counts every 30 minutes from baseline to 120 minutes for four different experimental groups for each combination of kitchen vents and windows. The results of the study demonstrate that aerosol counts were lowest with the kitchen exhaust vents on. This study suggests that liberal use of home exhaust systems like the kitchen vents could achieve significantly more air exchange than open windows alone and may present an effective solution to improving indoor ventilation, especially during the colder months when people tend to congregate indoors in closed spaces. There were no safety concerns involved when conducting this experiment.
Potential bias of preoperative intravitreal anti-VEGF injection for complications of proliferative diabetic retinopathy
Authors: Takayama Kei , Someya Hideaki , Yokoyama Hiroshi , Kimura Takeshi , Takamura Yoshihiro , Morioka Masakazu , Terasaki Hiroto , Ueda Tetsuo , Ogata Nahoko , Kitano Shigehiko , Tashiro Maki , Sakamoto Taiji , Takeuchi Masaru
Published: October 2021

Purpose

Intravitreal anti-VEGF injection (IVI) is administered before vitrectomy to assist management of proliferative diabetic retinopathy (PDR)-related complications. In the clinical setting, retinal surgeons determine the use of preoperative IVI based on individual criteria. In this study, we investigated factors related to the potential bias of retinal surgeons in using IVI prior to vitrectomy for PDR-related complications, and evaluated the real-world outcomes of surgeon-determined preoperative IVI.

Methods

Medical records of 409 eyes of 409 patients who underwent 25-gauge vitrectomy for PDR complications at seven Japanese centers (22 surgeons) were retrospectively reviewed. Ocular factors, demographic and general clinical factors, surgical procedures, and postoperative complications were compared between IVI group (patients who received preoperative IVI; 87 eyes, 21.3%) and non-IVI group (patients who did not receive preoperative IVI; 322 eyes, 78.7%). In addition, baseline HbA1c in IVI group and non-IVI group was compared between eyes with and without postoperative complications.

Results

At baseline, IVI group was younger (P<0.001), had shorter duration of diabetes treatment (P = 0.045), and higher frequencies of neovascular glaucoma [NVG] (P<0.001) and tractional retinal detachment [TRD] (P<0.001) compared to non-IVI group. Although IVI group had higher frequencies of intraoperative retinal break and tamponade procedure, there were no significant differences in postoperative complications and additional treatments between two groups. Baseline HbA1c levels were also not correlated with postoperative complications of VH, NVG, and RD both in IVI group and non-IVI group. Logistic regression analysis identified age (P<0.001, odds ratio [OR] 0.95), presence of NVG (P<0.001, OR 20.2), and presence of TRD (P = 0.0014, OR 2.44) as preoperative factors in favor of IVI.

Conclusions

In this multicenter real-world clinical study, younger age and presence of NVG and TRD were identified as potential biases in using IVI before vitrectomy for PDR complications. Eyes that received preoperative IVI had more intraoperative retinal breaks requiring tamponade than eyes not receiving IVI, but postoperative outcome was not different between the two groups.
Pathology and molecular characterization of Leucocytozoon caulleryi from backyard chickens in Khon Kaen Province, Thailand
Authors: Pohuang Tawatchai , Jittimanee Suphattra , Junnu Sucheeva
Published: October 2021

Aim: The aim of this study was to characterize Leucocytozoon caulleryi from backyard chickens in Khon Kaen Province, Thailand.

Materials and Methods: Tissue samples were collected from backyard chickens suspected to have leucocytozoonosis and subjected to histopathology examination. The BLAST Tool at NCBI GenBank (Basic Local Alignment Research Tools) (http://www.ncbi.nlm.nih.gov/BLAST) was used to identify the nucleotide sequence of the partial cytochrome c oxidase subunit I (cox I) gene. A Phylogenetic tree for analysis of L. caulleryi was constructed by using MEGA 7.0 software (https:// www.megasoftware.net/).

Results: The necropsy results revealed the subcutaneous hemorrhages of pectoral muscles, multifocal hemorrhages of the thymus and pectoral muscles, hemorrhage of the proventriculus and peritoneal cavity, and megaloschizonts of the pancreas and intestine, including subcapsular hemorrhages of the liver. Microscopic examination revealed numerous megaloschizonts of Leucocytozoon spp. in the pectoral muscles, intestine, pancreas, and thymus. Molecular analysis of the partial cox I gene showed that the causal agent was closely related to L. caulleryi reported in Japan.

Conclusion: From these results, L. caulleryi was determined to be the causal agent of leucocytozoonosis and was closely associated with L. caulleryi reported in Japan.
Can Digital Research be an Alternative Method during the COVID-19 Pandemic in Indonesia?
Authors: Rifai Bahtiar , Yayusman Meilinda Sari , Barid Vera Bararah
Published: October 2021

Unprecedented COVID-19 global pandemic entails uncertain conditions, which lead people to seek alternative solutions to make activities running accordingly. Limited movements due to travel restriction and health protection confine people’s activities, including the research process. Postponing research activities is arguably not the best solution for scholars, mainly while conducting data collection. In social and humanities research, researchers mostly undertake data collection through field studies and face-to-face communications prior to the pandemic. Social distancing procedures, however, encourage people to avoid close contacts and cancel visit plans. Thus, researchers are necessary to find an alternative method during uncertainty situation. Digital research method (DRM) seems to be a plausible way to keep research ongoing, although the implementation of that method in the developing countries’ research activities, compared to the developed countries, remains lagging behind. This research aims to position DRM amidst the pandemic situation and show possibilities in using this method as an alternative in the developing countries by taking Indonesia as a case study. Results show that to make DRM works in Indonesia, some requirements need to be fulfilled to meet academic standards, and whether relevant or not the research topic applies to be processed utilizing digital method are also essential to be considered.
KONTROL DEMOKRATIS ATAS KOMUNITAS INTELIJEN DI FILIPINA DAN INDONESIA
Authors: Kristimata Putri Ariza
Published: October 2021

Intelijen adalah lini pertama dalam pertahanan, yang berfungsi untuk menghindari pendadakan strategis dan memberikan rekomendasi bagi pembuat kebijakan dan pemangku kepentingan. Dalam negara demokrasi, prinsip-prinsip seperti akuntabilitas, transparansi, dan menjunjung tinggi hak-hak asasi manusia, menjadi sebuah benturan dalam prinsip kerahasiaan intelijen. Terlebih pada negara pasca otoriterisme seperti Filipina dan Indonesia, intelijen dijadikan alat pelanggengan rezim, alih-alih instrumen keamanan nasional. Oleh karena itu, kontrol demokratis dalam bentuk pengawasan terhadap komunitas intelijen mutlak dilakukan. Tulisan ini mengidentifikasi komunitas intelijen di Filipina dan Indonesia, serta bentuk pengawasan atas komunitas tersebut. Teori yang digunakan adalah model kontrol atau pengawasan Peter Gill, yang mengidentifikasi bentuk kontrol, institusi kontrol, dan institusi pengawas pada internal badan intelijen, cabang eksekutif, badan negara lainnya, dan kelompok masyarakat sipil. Pengumpulan data adalah dari wawancara dan penelusuran dokumentasi literatur. Hasil penelitian ini adalah (1) Filipina belum memiliki landasan hukum dan perangkat pengawasan yang memadai untuk memastikan anggaran dan kinerja intelijen akuntabel dan transparan; (2) Indonesia lemah dalam implementasi pengawasan meskipun sudah memiliki perangkat yang cukup memadai; (3) kelompok masyarakat sipil di kedua negara harus didorong agar berperan dalam fungsi pengawasan publik. Kedua negara dapat belajar satu sama lain. Filipina dapat belajar dari Indonesia karena memiliki perangkat regulasi pengawasan yang cukup memadai. Sementara Indonesia perlu memiliki arsitektur dan strategi keamanan nasional yang rigid agar BIN tidak langsung di bawah Presiden.
RELOKASI IBU KOTA NEGARA : LESSON LEARNED DARI NEGARA LAIN
Authors: Aziz Nyimas Latifah Letty
Published: October 2021

Artikel ini bertujuan untuk memberikan gambaran dan analisis tentang rencana relokasi ibu kota negara ditinjau dari pengalaman negara-negara lain. Selain itu, artikel ini juga bertujuan untuk memetakan persoalan terkait dengan dampak yang muncul akibat dari rencana relokasi ibu kota negara. Penulisan artikel ini menggunakan sumber data primer dan sekunder yang berasal dari koran, buku, media internet, dan sebagainya.  Relokasi ibu kota sudah dilakukan oleh beberapa negara. Ada beberapa negara yang berhasil merelokasi ibu kota negaranya dan memberikan dampak positif bagi pertumbuhan ekonomi dan peningkatan kinerja pemerintahannya tetapi ada pula negara yang berhasil merelokasi namun tidak memberikan dampak positif bagi pertumbuhan ekonomi baik di tempat baru maupun lama. Tentunya pemerintah perlu mempertimbangkan secara matang dampak dari relokasi ibu kota negara baik bagi ibu kota lama yang ditinggalkan dan dampak relokasi terhadap ibu kota  yang baru.
Effect of Various Veneering Techniques on Bond Strength and Colour Stability of Zirconia / Veneering Ceramic after Hydrothermal Aging
Authors: Sasany Rafat , Sarac Duygu , Kunt Goknil Ergun
Published: October 2021

BACKGROUND The purpose of this in-vitro study was to compare the colour stability and bond strength of zirconia-based ceramic restorations after hydrothermal aging using conventional layering, heat-pressing, and multilayer veneering techniques. METHODS One hundred twenty specimens’ core (15 x 10 x 0.7) was fabricated from A2-shade zirconia CAD-CAM blocks (IPS e.max ZirCAD). Specimens were divided into 4 groups for veneering (N = 30): [(layering group (L), IPS e.max ceram), (heat – pressing group (P), IPS press), and multilayer group, IPS e max Cad for 2 different types of cement (cemented with RelyX U200 (M1) and PANAVIA SA (M2))]. Aging was performed for (5 - 55°C, 5000). Colour coordinates before and after aging were measured to calculate colour differences (ΔE00). The shear bond strength test was performed with a universal test unit. The data were analysed using the analysis of variance (ANOVA) and Tukey’s Honest Significant Difference test (alpha = 0.05). RESULTS Significant differences were found between the groups in bond strength (P < 0.001). Group M1 had the highest bond strength while Group L had the lowest bond strength. In terms of ΔE00 values, there were significant variations between the groups (P < 0.001). Group M1 had the highest colour stability, while Group M2 had the lowest colour stability. CONCLUSIONS The method of fabrication had an impact on the power of the bond between veneering ceramic and zirconia, as well as its colour stability. The restoration fabricated by a multilayer technique was cemented by resin cement (Rely X U200 Automix) which was found to be more resistant and colour stable. KEY WORDS Veneers, Heat-Press Technique, Bond Strength, Colour Different, Hydrothermal Aging.
Accuracy of Free Hand Dental Implant Placement in a Private Dental College Setup - A Radiographic Analysis
Authors: Jebaraj Sam , R Subhasree , N. Thiyaneswaran , Rani Dimple
Published: October 2021

BACKGROUND The factors that influence the implant accuracy are the anatomy of the patient, the experience of the practitioner and the surgical approach. However, the relative importance of each factor is poorly understood. Favourable function, occlusion, aesthetics and implant loading patterns can be obtained by optimal positioning. The experience of the surgeon is of utmost importance for the skill of placing a dental implant with proper angulation. The purpose of this retrospective study was to determine the increased accuracy obtained in performing freehand surgical placement of implants. METHODS This study was conducted in the Department of Implantology. A total of 1216 postoperative periapical radiographs from which single implant placement with adjacent straight root morphology was collected from the department in the period of June 2019 to June 2020 and checked for angulation, practitioner’s experience and the site of placement. Mesio-distal angulation was calculated. Statistical analysis was performed using the SPSS method. RESULTS The results showed accuracy in angulation and positioning of implants increased with an increase in experience of the dental surgeon (oral surgeons, prosthodontists, periodontists). Within the limitations of the study, it showed that the freehand dental implant placement angulation was less than a degree for experienced surgeons. The postgraduates had a better understanding and orientation of the angulation than the undergraduates. Moreover, the difficult site was the second and third quadrant to assess the angulation properly. CONCLUSIONS With proper assessment of the anatomy and with experience freehand dental implant placement shows significant results with less angulation which can be prosthetically accepted. KEY WORDS Free Hand Surgery, Guided Surgery, Angulation Of Implants.
Extremes of cerebral blood flow during hypercapnic squat‐stand maneuvers
Authors: Barnes Samuel C. , Haunton Victoria J. , Beishon Lucy , Llwyd Osian , Robinson Thompson G. , Panerai Ronney B.
Published: October 2021

Squat‐stand maneuvers (SSMs) are a popular method of inducing blood pressure (BP) oscillations to reliably assess dynamic cerebral autoregulation (dCA), but their effects on the cerebral circulation remain controversial. We designed a protocol whereby participants would perform SSMs under hypercapnic conditions. Alarmingly high values of cerebral blood flow velocity (CBFV) were recorded, leading to early study termination after the recruitment of a single participant.

One healthy subject underwent recordings at rest (5 min sitting, 5 min standing) and during two SSMs (fixed and random frequency). Two sets of recordings were collected; one while breathing room air, one while breathing 5% CO2. Continuous recordings of bilateral CBFV (transcranial Doppler), heart rate (ECG), BP (Finometer), and end‐tidal CO2 (capnography) were collected.

Peak values of systolic CBFV were significantly higher during hypercapnia (p < 0.01), and maximal values exceeded 200 cm.s−1. Estimates of dCA (ARI) during hypercapnia were impaired relative to poikilocapnia (p = 0.03). The phase was significantly reduced under hypercapnic conditions (p = 0.03).

Here we report extremely high values of CBFV in response to repeated SSMs during induced hypercapnia, in an otherwise healthy subject. Our findings suggest that protocols performing hypercapnic SSMs are potentially dangerous. We, therefore, urge caution if other research groups plan to undertake similar protocols.
Transcriptional profiles of genes related to electrophysiological function in Scn5a+/− murine hearts
Authors: Takla Michael , Edling Charlotte E. , Zhang Kevin , Saadeh Khalil , Tse Gary , Salvage Samantha C. , Huang Christopher L.‐H. , Jeevaratnam Kamalan
Published: October 2021

The Scn5a gene encodes the major pore‐forming Nav1.5 (α) subunit, of the voltage‐gated Na+ channel in cardiomyocytes. The key role of Nav1.5 in action potential initiation and propagation in both atria and ventricles predisposes organisms lacking Scn5a or carrying Scn5a mutations to cardiac arrhythmogenesis. Loss‐of‐function Nav1.5 genetic abnormalities account for many cases of the human arrhythmic disorder Brugada syndrome (BrS) and related conduction disorders. A murine model with a heterozygous Scn5a deletion recapitulates many electrophysiological phenotypes of BrS. This study examines the relationships between its Scn5a+/− genotype, resulting transcriptional changes, and the consequent phenotypic presentations of BrS. Of 62 selected protein‐coding genes related to cardiomyocyte electrophysiological or homeostatic function, concentrations of mRNA transcribed from 15 differed significantly from wild type (WT). Despite halving apparent ventricular Scn5a transcription heterozygous deletion did not significantly downregulate its atrial expression, raising possibilities of atria‐specific feedback mechanisms. Most of the remaining 14 genes whose expression differed significantly between WT and Scn5a+/− animals involved Ca2+ homeostasis specifically in atrial tissue, with no overlap with any ventricular changes. All statistically significant changes in expression were upregulations in the atria and downregulations in the ventricles. This investigation demonstrates the value of future experiments exploring for and clarifying links between transcriptional control of Scn5a and of genes whose protein products coordinate Ca2+ regulation and examining their possible roles in BrS.
Micropattern platform promotes extracellular matrix remodeling by human PSC‐derived cardiac fibroblasts and enhances contractility of co‐cultured cardiomyocytes
Authors: Napiwocki B.N. , Stempien A. , Lang D. , Kruepke R.A. , Kim G. , Zhang J. , Eckhardt L.L. , Glukhov A.V. , Kamp T.J. , Crone W.C.
Published: October 2021

In native heart tissue, cardiac fibroblasts provide the structural framework of extracellular matrix (ECM) while also influencing the electrical and mechanical properties of cardiomyocytes. Recent advances in the field of stem cell differentiation have led to the availability of human pluripotent stem cell‐derived cardiac fibroblasts (iPSC‐CFs) in addition to cardiomyocytes (iPSC‐CMs). Here we use a novel 2D in vitro micropatterned platform that provides control over ECM geometry and substrate stiffness. When cultured alone on soft micropatterned substrates, iPSC‐CFs are confined to the micropatterned features and remodel the ECM into anisotropic fibers. Similar remodeling and ECM production occurs when cultured with iPSC‐CMs in a co‐culture model. In addition to modifications in the ECM, our results show that iPSC‐CFs influence iPSC‐CM function with accelerated Ca2+ transient rise‐up time and greater contractile strains in the co‐culture conditions compared to when iPSC‐CMs are cultured alone. These combined observations highlight the important role cardiac fibroblasts play in vivo and the need for co‐culture models like the one presented here to provide more representative in vitro cardiac constructs.
Intra‐rater reliability of leg blood flow during dynamic exercise using Doppler ultrasound
Authors: Amin Sachin B. , Mugele Hendrik , Dobler Florian E. , Marume Kyohei , Moore Jonathan P. , Lawley Justin S.
Published: October 2021

Developing an exercise model that resembles a traditional form of aerobic exercise and facilitates a complete simultaneous assessment of multiple parameters within the oxygen cascade is critically for understanding exercise intolerances in diseased populations. Measurement of muscle blood flow is a crucial component of such a model and previous studies have used invasive procedures to determine blood flow kinetics; however, this may not be appropriate in certain populations. Furthermore, current models utilizing Doppler ultrasound use isolated limb exercise and while these studies have provided useful data, the exercise model does not mimic the whole‐body physiological response to continuous dynamic exercise. Therefore, we aimed to measure common femoral artery blood flow using Doppler ultrasound during continuous dynamic stepping exercise performed at three independent workloads to assess the within day and between‐day reliability for such an exercise modality. We report a within‐session coefficient of variation of 5.8% from three combined workloads and a between‐day coefficient of variation of 12.7%. These values demonstrate acceptable measurement accuracy and support our intention of utilizing this noninvasive exercise model for an integrative assessment of the whole‐body physiological response to exercise in a range of populations.
Deletion of Sphingosine 1‐Phosphate receptor 1 in cardiomyocytes during development leads to abnormal ventricular conduction and fibrosis
Authors: Jorgensen Ryan , Katta Meghna , Wolfe Jayne , Leach Desiree F. , Lavelle Bianca , Chun Jerold , Wilsbacher Lisa D.
Published: October 2021

Sphingosine 1‐Phosphate receptor 1 (S1P1, encoded by S1pr1) is a G protein‐coupled receptor that signals in multiple cell types including endothelial cells and cardiomyocytes. Cardiomyocyte‐specific deletion of S1pr1 during mouse development leads to ventricular noncompaction, with 44% of mutant mice surviving to adulthood. Adult survivors of embryonic cardiomyocyte S1pr1 deletion showed cardiac hypertrabeculation consistent with ventricular noncompaction. Surprisingly, systolic function in mutant mice was preserved through at least 1 year of age. Cardiac conduction was abnormal in cardiomyocyte S1pr1 mutant mice, with prolonged QRS intervals in mutants as compared with littermate control mice. Immunostaining of hearts from S1pr1 mutant embryos displayed a zone of intermediate Connexin 40 (Cx40) expression in the trabecular myocardium. However, we observed no significant differences in Cx40 and Connexin 43 immunostaining in hearts from adult survivors of embryonic cardiomyocyte S1pr1 deletion, which suggests normalized development of the ventricular conduction system in mutant mice. By contrast, the adult survivors of embryonic cardiomyocyte S1pr1 deletion showed increased cardiac fibrosis as compared with littermate controls. These results demonstrate that ventricular hypertrabeculation caused by embryonic deletion of cardiomyocyte S1pr1 correlates with cardiac fibrosis, which contributes to abnormal ventricular conduction. These results also reveal conduction abnormalities in the setting of hypertrabeculation with normal systolic function, which may be of clinical relevance in humans with ventricular hypertrabeculation.
Factors Contributing to Fatigue Cracking in Flexible Pavements in Oklahoma: A Case Study Using Laboratory and Field Investigation and AASHTOWare Simulation
Authors: Ghos Sagar , Ashik Ali Syed , Zaman Musharraf , Hobson Kenneth R. , Mendez Larrain Matias , Behm Michael
Published: October 2021

Fatigue cracking is one of the major structural distresses in flexible pavements. In this study, probable causes of fatigue cracking were investigated using field and laboratory testing and In this study, probable causes of fatigue cracking were investigated using field ang laboratory testing and AASHTOWare Pavement ME Design (PMED) simulations. Field tests including Ground Penetrating Radar (GPR), Falling Weight Deflectometer (FWD), and Dynamic Cone Penetration (DCP) were performed on a flexible pavement section of US 412 located in Noble County, Oklahoma. Also, asphalt cores and soil samples were collected for laboratory testing. The GPR test results revealed significant delamination in the asphalt layer. Also, the GPR images indicated that the disturbance zone was confined within the asphalt layer and cracks were generated from surface as well as from existing pavement layers below. The DCP and FWD test results indicated that the pavement section was not structurally adequate to support traffic and needed rehabilitation in the near future. The moduli of the asphalt layers were found to be quite low, indicating improper compaction during construction. Also, the densities of the top-lifts of the asphalt cores were found to be low. Moreover, the cracking resistance of the extracted asphalt cores was poor based on the Illinois flexibility index test results. Superpave Performance Grade of the extracted binder indicated excessive aging of the binder because of long exposure to the environment. The brittleness of mix resulting from aging was considered a potential contributor to fatigue cracking of the pavement at this site. A parametric study was conducted to understand the variation of fatigue cracking with the changes in input properties in PMED, namely pavement structural components and material properties. Pavement thickness, roadway densities, and layer moduli of existing underlying pavement were found as the most influential factors. The findings of the parametric study supported the findings of the field and laboratory investigation.
On the Densification of Cold Recycled Asphalt Mixtures
Authors: Mignini Chiara , Virgili Amedeo , Graziani Andrea
Published: October 2021

The mechanical behavior of cold recycled asphalt mixtures (CRAMs) is directly connected to their volumetric properties. Therefore, the objective of the present research was to investigate the effect of different composition factors on the densification of CRAMs. To this aim, a new empirical modeling approach for characterizing and comparing the densification of CRAMs using the gyratory compactor was proposed. The methodology was then applied to CRAMs produced using four gradations, two asphalt emulsions, two cements, various water contents, and several superplasticizer dosages. The densification curves were analyzed using three parameters representing the self-densification, the compactability, and the compaction energy. These parameters were linked using a mathematical model, which was represented using three interrelated pairwise relationships. The results showed that the grading distribution of the CRAMs was the main parameter controlling their densification behavior, whereas the water content and other composition factors played a minor role.
Microstructure and Mechanical Properties of Dissimilar Aluminum Alloys AA5052-H32 and AA2219-T31 Welded Using Cold Metal Transfer Process
Authors: Rajesh Kannan A. , Mohan Kumar S. , Pramod R. , Siva Shanmugam N. , Palguna Yasam , Vishnukumar M.
Published: October 2021

Lightweight structures fabricated from dissimilar aluminum alloys in aerospace and marine industries involve a lot of welding. Aluminum alloys AA5052-H32 and AA2219-T31 were successfully welded with the low heat input welding technology, the cold metal transfer (CMT) process. Microstructures indicated the existence of finer equiaxed dendrites and strengthening precipitates in the weld metal (WM). The microliquefaction cracks were discontinuous and propagated along the grain boundaries and with the grains of α-Al matrix in the WM. The tensile properties of the dissimilar welded joint attained a joint efficiency of 70.1 % and fracture ended in ductile nature with dimples and microvoids. The heat affected zone was narrow and noticed a drop in the hardness at both the interfaces caused by a softening phenomenon, ending up with coarse precipitates having lower hardness.
Selection of sorption materials for the extraction of nickel and cobalt from the ore of the Gornostaevskoye deposit
Authors: Panova Yelena , Aubakirov Yermek , Arbag Huseyin
Published: October 2021

Oxidized nickel ores account for the majority of industrial ores suitable for nickel production. The processing of such ores using traditional pyrometallurgical technology is not economically viable due to the low nickel content. One of the most cost-effective methods of processing oxidized nickel ores is sulfuric acid leaching technology followed by sorption extraction. The aim of this work is to establish the kinetic and thermodynamic parameters of the sorption extraction of nickel and cobalt using iminodiacetate chelating ion-exchange sorbents from various manufacturers, to select a desorbing solution and to determine the degree of desorption. The sorption of nickel and cobalt was carried out in a weakly acidic medium from a model solution containing impurities of other metals in static and dynamic modes. The limiting sorption capacity for the studied sorbents is 18-26 mg/g for nickel and 1-2 mg/g for cobalt in the static mode. The sorption capacity in the dynamic mode for nickel is equal to 25.5 g/L for Purolite S 930, 29.2 g/L for Lewatit TP 207, 1.4 g/L, and 1.8 g/L for cobalt, respectively. The best desorption parameters are achieved when using a 2 M sulfuric acid solution. The degree of desorption for sorbents Purolite S 930 and Lewatit TP 207 exceeds 90%. The use of the Lewatit TP 207 sorbent for the extraction of nickel from the leaching solution of nickel ore of the Gornostaevskoye deposit in 5 cycles made it possible to obtain a commercial desorbate with a nickel content of 18 g/L. The use of a part of the commercial desorbate obtained in the previous cycle, further strengthened to the initial concentration of sulfuric acid, for re-extracting nickel from the saturated sorbent during a cyclic process leads to a deterioration in desorption characteristics. It is recommended to remove the commercial desorbate from the process after several cycles of desorption and supply new solution of sulfuric acid for desorption to restore the sorption parameters.
Powder bismuth-based anode material for magnesium-ion batteries and its properties
Authors: Abildina Ainaz , Dzhumanova Raigul , Rakhymbay Gulmira , Beiseyeva Assemay , Argimbayeva Akmaral
Published: October 2021

In this work an intercalation anode material synthesized on the base of the powdered bismuth is presented. The uniformly distribution of carbon paste suspension over the substrate surface was found out by scanning-electron microscopy. The regularities of electrochemical intercalation and deintercalation of magnesium ions into the electrode created on the base of powdered bismuth in a solution of 0.25 mol/L Mg(N(SO2CF3)2)2 on the base of acetonitrile were studied. The cyclic voltammograms with the results of scanning electron microscopy and atomic emission analysis indicate that in the cathode area the reduction processes proceed with the formation of an intermetallic compound – MgxBiy; two peaks were observed at the reverse course which were conceivably corresponding to two-stage magnesium oxidation. According to cyclic voltammograms by the difference in the potential of peaks in the forward and reverse directions it was established that the processes of reduction and oxidation of magnesium ions into intercalation material were irreversible. The diffusion coefficients of intercalation and deintercalation into the electrode material were calculated using the Rendles-Shevchik equation; they were 3.12·10-11 sm2/s and 1.85·10-11 sm2/s, respectively. X-ray diffraction (XRD) results demonstrated the cubic structure of the bismuth crystal lattice with altered parameters corresponding to inter-metallide formation. At galvanostatic cycling of the synthesized anode material a capacity of up to 104 mA·h·g-1 at current load 1C was achieved. Such results can be a good indicator for the development of magnesium-ion power sources.
Preparation and study of the physicochemical characteristics of multilayer polymer composites based on poly(ethyleneimine)-stabilized copper nanoparticles and poly(sodium 2-acrylamide-2-methyl-1-propanesulfonate)
Authors: Selenova Bagadat , Ayazbayeva Aigerim , Shakhvorostov Alexsey , Kabdrakhmanova Sana , Nauryzova Saule , Kudaibergenov Sarkyt
Published: October 2021

Multilayer films were synthesized from a complex of branched polyethyleneimine (PEI) with copper nanoparticles (PEI-CuNPs) and sodium poly-2-acrylamide-2-methyl-1-propanesulfonate (PAMPSNa), applied layer-by-layer (LbL) on a solid support in an acidic medium. Protonation of the amino groups of PEI in an acidic medium increases the positive charge of the PEI-CuNPs system to +43.5 mV and promotes the formation of an interpolyelectrolyte complex between the positively charged PEI-CuNPs and the highly charged anionic polyelectrolyte PAMPS, the ζ-potential of which was -141 mV. AFM images and SEM micrographs showed a uniform distribution of spherical copper nanoparticles in the homogeneous structure of the multilayer film. The optical characteristics and hydrodynamic dimensions of PEI-CuNPs indicate the formation of PEI-CuNPs nanoparticles with sizes of 60-300 nm, with an average size of up to 100 nm. Copper nanoparticles distributed uniformly in a multilayer PEI-CuNPs/PAMPS film may be of interest for applications in the field of membrane catalysis, biochips, sensor membranes, and controlled drug delivery.
Synthesis of nanocomposite material through modification of graphene oxide by nanocellulose
Authors: Akatan Kydyrmolla , Kuanyshbekov Tilek , Kabdrakhmanova Sana , Imasheva Aidana , Battalova Ainur , Abylkalykova Riza , Nasyrova Anar , Ibraeva Zhanar
Published: October 2021

Intensive research of nanocomposites contributes to the development of new materials in the fields of medicine, nanoelectronics, energy, biotechnology, information technology. Therefore, the synthesis of new materials by modifying of graphene oxide (GO) with nanocellulose and the study of its properties are of great interest. In this study synthesized nanocomposite material by modifying of graphene oxide (GO) from activated carbon (BAU-A) in a 1:1 volume ratio with nanocellulose (NC) from hemp stems belonging to the annual plant, and their chemical structure was studied by FTIR and UV-spectroscopy. The results of the study showed the absorption of the etheric bond C = O in the UV spectrum at full length 243 nm. The IR spectrum showed all the new etheric bonds O = C - OH at a wavelength of 1625 cm-1. The average particle sizes of GO was 352 nm and NC was 470 nm in length and 80 nm in width. The SEM analysis indicating the NC as a contact layer between ultralow thicknesses of the GO layers. The XRD analysis indicated GO-NC composite film is a substance comprising GO and NC. According to the results, modification of graphene oxide showed that its scope can be expanded as much as possible.
Optical Soliton Solutions of Fokas-Lenells Equation via (m + 1/G')- Expansion Method
Authors: Bulut, Hasan  , Khalid, Ban Jamal
Published: October 2021

In this research paper, we investigate some novel soliton solutions to the perturbed Fokas-Lenells equation by using the (m + 1/G') expansion method. Some new solutions are obtained and they are plotted in two and three dimensions. This technique appears as a suitable, applicable, and efficient method to search for the exact solutions of nonlinear partial differential equations in a wide range. All gained optical soliton solutions are substituted into the FokasLenells equation and they verify it. The constraint conditions are also given.
Approaching explanatory adequacy in phonology using Minimum Description Length
Authors: Rasin Ezer , Berger Iddo , Lan Nur , Shefi Itamar , Katzir Roni
Published: October 2021

A linguistic theory reaches explanatory adequacy if it arrives at a linguistically-appropriate grammar based on the kind of input available to children. In phonology, we assume that children can succeed even when the input consists of surface evidence alone, with no corrections or explicit paradigmatic information – that is, in learning from distributional evidence. We take the grammar to include both a lexicon of underlying representations and a mapping from the lexicon to surface forms. Moreover, this mapping should be able to express optionality and opacity, among other textbook patterns. This learning challenge has not yet been addressed in the literature. We argue that the principle of Minimum Description Length (MDL) offers the right kind of guidance to the learner – favoring generalizations that are neither overly general nor overly specific – and can help the learner overcome the learning challenge. We illustrate with an implemented MDL learner that succeeds in learning various linguistically-relevant patterns from small corpora.
Error Bounds Related to Midpoint and Trapezoid Rules for the Monotonic Integral Transform of Positive Operators in Hilbert Spaces
Authors: Dragomir Silvestru Sever
Published: October 2021

For a continuous and positive function w(λ), λ > 0 and μ a positive measure on (0, ∞) we consider the followingmonotonic integral transform

where the integral is assumed to exist forT a positive operator on a complex Hilbert spaceH. We show among others that, if β ≥ A, B ≥ α > 0, and 0 < δ ≤ (B − A)2 ≤ Δ for some constants α, β, δ, Δ, then

and

where is the second derivative of as a real function.

Applications for power function and logarithm are also provided.
Circles of Curvature at Points of Parabola in Isotropic Plane
Authors: Volenec Vladimir , Horvath Marija Šimić , Jurkin Ema
Published: October 2021

The authors have studied the curvature of the focal conic in the isotropic plane and the form of the circle of curvature at its points has been obtained. Hereby, we discuss several properties of such circles of curvature at the points of a parabola in the isotropic plane.
Atkafélék okozta, bőrtünetekkel járó humán megbetegedések
Authors: Budai Dóra , Barna Tibor , Nagy Gabriella
Published: October 2021

Összefoglaló. Az atkák alosztálya heterogén csoport. Az eltérő
megjelenésű és életformájú atkák növényeken, állatokon és embereken is képesek
különféle megbetegedéseket okozni, melyek csípés, táplálkozás, élősködés,
vektorként terjesztett kórokozók által valósulhatnak meg. Az atkák okozta
betegségek a lokális, spontán szűnő csípéstől egészen a sokszervi elégtelenséget
okozó fertőző betegségig széles skálán mozognak. Munkánk során az atkafélék
által okozott humán megbetegedések előfordulását, klinikai megjelenését,
differenciáldiagnosztikáját, kezelését és közegészségügyi jelentőségét mutatjuk
be. Orv Hetil. 2021; 162(36): 1430–1437.

Summary. The Acari subclass is a heterogeneous group. They have
different appearance and lifestyle. They can cause different diseases on plants,
in animals and in humans. These illnesses can be caused by their bites,
nutrition, parasitism and by their endoparasites. The diseases move on a wide
scale from a local, spontaneously disappearing bite to an infection caused
multiorgan failure. We would like to summarize the Acari-caused human diseases’
incidence, clinical symptoms, diagnostics, differential diagnostics, treatments
and public health importance. Orv Hetil. 2021; 162(36): 1430–1437.
International Actorness Status of Terrorist Organizations in Terms of Classical Realism: Their Usage as an Instrument
Authors: ÖRKİ Armağan , ARIKAN Nurullah , TOL Mehmet Aydın
Published: October 2021

Terrorist organizations are one of the non-state armed actors that threaten national and international security. The approach towards the terrorist organizations has gained a new momentum especially after the terrorist attacks which were carried out on September 11, 2001 and have started to gain a seat more frequently in international relations and international security studies.Classical realism is one of the most frequently cited traditional theories in case studies in international relations. According to classical realism, where the state is considered the only actor, the system in international relations is based on anarchy. States focus primarily on their own interests. States that do not hesitate to open war if necessary act in their own interests, and cooperation is impossible. Terrorist organizations are also a foreign policy tool according to classical realism. Terrorist organizations, which are used as a tool used in proxy wars, also have some advantages in terms of the state that uses them. According to classical realism, which argues that ethical and moral rules are not important in foreign policy, there is no point in acting in accordance with human values in achieving success.In studies conducted regarding terrorist organizations, there are also subjects where consensus cannot be reached. One of those is that the question of whether or not they are an international actor like states. Terrorist organizations have the ability to deter individuals by frightening them as an armed element. They can even play a role in shaping domestic and foreign policies of states. In addition to this, it is also known that they get direct or indirect support.The main focus of this work is whether or not the terrorist organizations, which have taken the form of an instrument in the foreign policies of states by receiving aid from them, can be accepted as an international actor in the real sense. In order to find the correct answer, the concepts of proxy war and hybrid war were addressed; the difference between state sponsored terror and state terrorism was examined and the approach of realists to legal entities that are accepted by some theories as non-state actors were studied. In the main chapter, a focus was placed on drawing a conclusion by searching for an answer to the question.
Sosyal Medyanın Turizm Öğrencilerinin Üniversite Tercih Sürecine Etkisi Üzerine Bir Araştırma
Authors: KARAKAŞ TANDOĞAN Gülnur , BİLGİÇ Yunus Emre
Published: October 2021

İnternetin ve özellikle de sosyal medyanın gün geçtikçe yaygınlaşması, insanların iletişim ve bilgi edinme gibi konularda bu platformlarda daha aktif hale gelmesini sağlamıştır. Üniversite tercih süreci öğrenci için geniş çaplı bir araştırma yapmasını gerektirecek, bu konuda bilgi edinme amacıyla sosyal medyadan faydalanabileceği bir süreçtir. Bu nedenle çalışmada öğrencilerin sosyal medya üzerinde üniversite ile ilgili bilgi edinmeleri sırasında nelere dikkat ettiklerinin ve üniversitelerin potansiyel öğrencileriyle ne şekilde iletişim kurmaları gerektiğinin tespit edilmesi amaçlanmıştır. Araştırma, lisans ve önlisans turizm eğitimi alan 230 üniversite öğrencisinin katılımıyla Nisan-Mayıs 2020 tarihleri arasında Google Forms üzerinden kendilerine ulaştırılan anket aracılığıyla gerçekleştirilmiştir. Araştırma sonuçlarına göre, katılan öğrencilerin %97,4'ü sosyal medyayı aktif olarak kullanmaktadır. Bu nedenle üniversitelerin sosyal medyadaki varlıklarını güçlendirmeleri çok önemli ve gereklidir. Araştırmaya katılan öğrencilerin en çok tercih ettikleri sosyal medya platformları %91,7 ile Instagram ve %80 ile YouTube’dur. Bu bilgilerle üniversitelerin Instagram ve Youtube hesaplarını daha aktif kullanmalarının öğrencilere ulaşmayı kolaylaştıracağı söylenebilir. Ayrıca sosyal medya ölçeğinde açıklayıcı faktör analizi yapılmış ve analiz sonucunda 3 boyut elde edilmiştir: sosyal medya algısı, sosyal medya araçlarının tercihe etkisi ve sosyal medyaya yönelik tutum. Cronbach Alpha ile yapılan güvenilirlik analizi sonucunda toplam 3 faktörün güvenirlik katsayıları incelendiğinde 1. Faktör ,878, 2. faktör ,854 ve 3. faktör ,891 olduğu görülmüştür. Sosyal Medya ölçek boyutlarının güvenilir olduğu ve bu boyutlar arasında yapılan korelasyon analizi sonucunda boyutların birbirleriyle pozitif bir ilişki içinde olduğu görülmektedir. Katılımcıların demografik özellikleri ile bahsedilen sosyal medya boyutları arasındaki farklılıkları belirlemek için hipotezler geliştirilmiştir. Araştırma sonucunda öğrencilerin öğrenim durumlarının sosyal medyayı algılamalarında; sosyal medyayı ne kadar süredir kullandıklarının ise sosyal medyaya karşı tutumlarında etkili olduğu saptanmıştır. Ayrıca katılımcıların tercih ettikleri sosyal medya kanallarının da sosyal medyaya karşı tutumlarında etkili olduğu tespit edilmiştir. Örneğin, Twitter kullanan katılımcıların kullanmayanlara göre tercih sürecinde sosyal medyadan daha fazla etkilendikleri, sosyal medya algısının ise Instagram kullanıcıları arasında daha olumlu olduğu görülmüştür.
Farklı Meslek Grupları Bağlamında Toplumsal Cinsiyet Algısı ve Dindarlık Düzeyi Arasındaki İlişki
Authors: AYGÜN Şehriban , TEKİN Saliha , ÖZDEMİR Reyhan
Published: October 2021

Toplum hayatındaki kültürel unsurların en önemlilerinden birinin cinsiyet algıları olduğu söylenebilir. Zira cinsiyet algıları, bireylerin içinde yaşadıkları toplum tarafından cinsiyetlere yapılan çeşitli tutum, davranış ve yaşayış şekli yüklemeleri olarak ifade edilmektedir. Toplumun erkek ve kadınlardan cinsiyetlere dair beklentileri bu kavram ile açıklanmaktadır. Toplumsal yaşamda, kültür unsurları ile etkileşim halinde olduğu düşünülen kavramların en önemlilerinden biri, din olgusudur. Dinlerin bu rolünün, insan hayatının her alanına temas etmesi ve bireyin karşılaşabileceği hemen hemen her konu ile ilgili hükümlere sahip olması özelliğinden kaynaklandığını söylemek mümkündür. İnsanların, sahip olduğu kültürel değerler ve normları, meslek seçimlerine ve mesleki yaşantılarına taşıdıkları düşünülerek farklı meslek gruplarında, toplumsal cinsiyet algısı ve dindarlık kavramları araştırılmak istenmiştir.Toplumsal cinsiyet algısını ve dindarlık kavramını, farklı kavramlarla ilişkilendiren çeşitli araştırmalar yapılmaktadır. Bu çalışma kapsamında, bu iki değişkenin arasındaki muhtemel ilişkinin, farklı mesleklerdeki durumuna odaklanılmıştır. Bu çerçevede çalışmanın temel amacı; toplumsal cinsiyet algısı ile dindarlık düzeyi arasında bir ilişkinin olup olmadığını belirlemek; böyle bir ilişki var ise farklı meslek gruplarına göre nasıl bir değişim gösterdiğini ortaya koymaktır. Araştırmada kullanılan anket formu, değişik meslek gruplarında çalışan, öğrencilik süreci devam eden veya ev hanımı olan bireylere, kartopu yöntemiyle, online olarak ulaştırılmıştır. Ulaşılan kişi sayısı 596 olup 546 kişinin verisinin değerlendirmeye alınabilir nitelikte olduğu görülmüştür. Araştırma bulgularına göre iki temel sonuca ulaşılmıştır. Birincisi; toplumsal cinsiyet algısı ile dindarlık düzeyi arasında negatif yönlü bir ilişki olduğu bulgusudur. İkincisi; öğrencilerde, eğitim sektöründe, sosyal ve beşeri bilimler alanlarında ve emniyet mensubu olarak çalışan kişilerde, genel sonuçla paralel olarak iki değişken arasında negatif yönlü bir ilişki tespit edilmesi ve diğer meslek gruplarında değişkenler arasında herhangi bir ilişki bulunamamış olmasıdır.