bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Utilitarian, Hedonic, Monetary and Social Value on Users of Mobile Wallets
Authors:   Cochin University of Science and Technology, XAVIER Smitha , ZAKKARIYA K.A. ,   Cochin University of Science and Technology
Published: December 2022

The purpose of this paper is to explore the factors that affect the usage continuance intention of mobile wallet users. A number of studies on mobile wallets have used various theories like TAM and UTAUT to understand the adoption intention, but the studies on continuous intention are scant. The study findings are based on the data collected from 485 respondents and analysed using AMOS SEM. The role of engagement in the relationship between value and continuance intention was also explored using mediation analysis. The study’s results prove the importance of value in bringing about an engrossed state in the users of mobile wallets, thereby increasing the intention of these users to continue using the wallet. From a theoretical perspective, the study is one of the first to explore the relationship between value, engagement, and continuance intention among mobile wallet users. As far as practical implications are concerned, the study’s results reveal the importance of value in inducing engagement among users and, thereby, loyalty, especially in an industry where the switching costs are low.
Contagion Effects of Covid-19 on Select Stock Market Indices
Authors:   K J Somaiya Institute of Management, KALPAKAM Gopalakrishnan , RAMAKRISHNA Smita ,   K J Somaiya Institute of Management
Published: December 2022

We examine the impact of the COVID-19 pandemic on the interlinkages between the Indian stock market and some of the largest indices across the world. We compare the co-movements of these stock markets to identify the possibilities for international portfolio diversification. We use the Johansen cointegration technique and Vector Error Correction Mechanism to understand the nature of long-run and short-run cointegration. We also apply the Impulse Response Function to understand the time effects of the shock. The results of the Johansen cointegration test indicate that there is an increased level of cointegration among the stock market indices post the pandemic. Our results of VEC Block Exogeneity Wald Tests indicate that in the preCovid time, there were linkages between the stock markets of India and the U.K., Japan, and Hongkong. However, the post-pandemic results indicate the shock transmission effects from India to two very important European indices, i.e., the U.K. and Euronext stock exchanges, and to the stock market of Japan. We also observe transmission effects from the USA to India post-Covid period.
Türklerin Nüfûzu Altında Abbâsî Hilâfetinin Görünümü (Sâmerrâ Dönemi)
Authors: Arslan İhsan
Published: December 2022

Bu araştırmada Türklerin Samerrâ döneminde Abbâsî hilâfeti üzerindeki etkileri metodolojik bakış açısıyla ve temel İslâm tarihi kaynakları referans alınarak işlenmiştir. Rivâyetlerden hareketle Türklerin, Abbâsî ihtilal hareketinin başarıya ulaşmasındaki rolleri, yeni devletin kurulmasıyla birlikte yönetim mekanizmasındaki âskerî faaliyetleri, Me’mûn’un hilâfete gelmesindeki katkıları ve bu dönemde Mu’tasım’ın emri altında isyan hareketlerindeki başarıları vurgulanmıştır. Yapılan incelemede Mu’tasım’ın hilafete gelmesindeki etkilerinden dolayı büyük bir güce sahip olmaları sebebiyle Bağdat’ta disiplinsiz davranışlarından dolayı kendileri için 222/836 tarihinde inşa edilen Sâmerrâ şehrine nakledilmeleri üzerinde durulmuştur. Türk asrı veya Sâmerrâ dönemi olarak bilinen bu süreçte onların halifeler üzerindeki etkileri siyasî, idarî, askerî, iktisadî ve ictimaî sahalarda yakın bir şekilde hissedilmeye başlanmıştır. Mütevekkil Alellâh’ın hilâfet makamına gelmesindeki rollerinden sonra ise, Halife’yi öldürebilecek kadar güçlü hale gelmişlerdir. Bu hadiseden sonra onlar, hilâfet makamına istedikleri halifeleri getirdikleri için yönetim üzerinde oldukça etkili olmuşlar ve kendi menfaatlerine uygun düşmeyen halifeleri ya hilâfetten uzaklaştırarak hapse atmışlar ya da öldürmüşlerdir. Ancak Mu’temid Alellâh’ın halife olmasından sonra Zenc isyanının bastırılmasında, Saffârîler ile mücadelede ve Bizans seferlerinde pek çok Türk komutan ve asker ölmesi, onların hilâfet üzerindeki etkilerini kırmıştır. Araştırma neticesinde bu durumu fırsat bilen Mutemid Allellâh’ın 277/890 tarihinde tekrar başkenti Bağdat’a taşıyarak Sâmerrâ dönemine son verdiği sonucuna ulaşılmıştır.
Relationship between Board Characteristics, ESG and Corporate Performance: A Systematic Review
Authors: Попов Константин , Макеева Елена
Published: December 2022

In recent years researchers have been paying significant attention to Environmental, Social, Governance (ESG) principles as a crucial factor in company performance. This paper aims to summarize the trends and findings in academic literature devoted to the board of directors as a determinant of ESG performance and non-financial disclosure quality. This paper also summarizes the key findings for a board’s moderating effects on the impact of ESG on corporate financial performance. The results of qualitative analysis of more than 70 empirical papers demonstrate that board independence is the most widely considered parameter, interpreted as a positive factor for strengthening a board’s monitoring function according to agency theory. There is no consensus on board size: larger boards include directors who represent the interests of a wider range of stakeholders (stakeholder theory), however, the increase in board size leads to a complicationof decision-making and controlling processes. Researchers mostly agree that an augmentation of women’ and foreigners’ representation among directors positively affects ESG performance and disclosure quality, although the lack of critical mass may dilute this effect. As for CEO’s role in the board, while some researchers argue that CEO duality enhances agency conflict, deterring corporate transition to ESG, other authors claim that a CEO’s organizational power may enhance the ESG transition due to a faster implementation of board decisions. One of the crucial determinants for this effect is the board members’ diversified professional expertise, including specialized education and experience, for the effective monitoring of managers’ performance. Finally, there is a growing interest in the role of board sustainability committees,which accumulate the required professional expertise for developing environmental and social strategies (resource-based theory). By examining the key board characteristics’ effect on corporate ESG performance and disclosure quality, this paper contributes to corporate governance literature, expanding the field for further research. Moreover, the paper highlights several understudied issues for further research.
Synthesis, Characterization, Anti-Glycation, and Anti-Oxidant Activities of Sulfanilamide Schiff Base Metal Chelates
Authors: Yaqoob Muhammad , Jamil Waqas , Taha Muhammad , Solangi Sorath
Published: December 2022

The current study reports synthesis, structure establishment, anti-glycation, and anti-oxidant activities of ligand 4-[(2-hydroxynaphthalene-1-ylmethylene)-amino]-benzenesulfonamide (L) and its coordination compounds with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) metal ions. The analytical techniques used (UV-Vis, FT-IR, CHN/S) confirmed the bidentate nature of the ligand, coordinating via O and N atoms in 2:1 ligand-to-metal ratio. The TG/DTA anylsis displayed that these compounds are thermally stable. Furthermore, the synthesized compounds were evaluated for their anti-glycation and antioxidant potential and showed significant activities with IC50 values range 184.11–386.34 μM and 37.05–126.27 μM, respectively. The Mn (IC50 = 184.11 ± 2.11 μM), Ni (IC50 = 211.26 ± 1.46 μM), Cu (IC50 = 254.56 ± 1.16 μM), and Zn (IC50 = 276.43 ± 2.14 μM) metal complexes exhibited substantial anti-glycation activity and comparatively better activity than the standard rutin (IC50 = 294.4 ± 1.50 μM), whereas Zn complex (IC50 = 37.05 ± 1.53 μM) also showed better DPPH radical scavenging activity than the standard tert-butyl-4-hydroxyanisole (IC50 = 44.7 ± 1.21 μM).
Tetranuclear Copper(II) Complexes Derived from 5-Bromo- 2-((2-(2-hydroxyethylamino)ethylimino)methyl)phenol: Synthesis, Characterization, Crystal Structures and Catalytic Oxidation of Olefins
Authors: Zhao Xiao-Jun , Bai Su-Zhen , Xue Ling-Wei
Published: December 2022

An acetate bridged tetranuclear copper(II) complex, [Cu4L2(μ2-η1:η1-CH3COO)6(CH3OH)2] (1), and a chloride, phenolate and azide co-bridged tetranuclear copper(II) complex, [Cu4L2Cl2(μ-Cl)2(μ1,1-N3)2]2CH3OH (2), where L is the deprotonated form of the Schiff base 5-bromo-2-((2-(2-hydroxyethylamino)ethylimino)methyl)phenol (HL), have been synthesized and characterized by elemental analysis, IR and UV spectra, and single crystal X-ray diffraction. Single crystal X-ray analysis revealed that the Cu atoms in both complexes are in square pyramidal geometry. In complex 1, two [CuL] units and [Cu2(μ2-η1:η1-CH3COO)4] core are linked through two acetate ligands. In complex 2, [Cu2LCl(μ-Cl)] units are linked together by two end-on azido ligands. The Schiff base ligand coordinates to the Cu atoms through four N and O donor atoms. The molecules of both complexes are linked through hydrogen bonds to generate three dimensional networks. The catalytic property of the complexes for epoxidation reactions of some alkenes was studied using tert-butylhydroperoxide as the terminal oxidant under mild conditions in acetonitrile.
Evaluation of the Stability of Hydrocortisone Sodium Succinate in Solutions for Parenteral Use by a Validated HPLC-UV Method
Authors: Mihovec Katja , Temova Rakuša Žane , Gaál Enikő Éva , Roškar Robert
Published: December 2022

This study aimed to determine the in-use stability (t95%) of hydrocortisone sodium succinate (HSS) infusion solutions and provide evidence-based guidelines on their usability. HSS infusion solutions were prepared and stored as recommended by the manufacturer and under common conditions in our hospital. The effects of HSS concentration (1 and 4 mg/mL), solvent (isotonic saline and glucose), temperature (ambient and 30 °C), and light on its stability were evaluated using a validated stability-indicating HPLC-UV method. HSS degradation followed first-order kinetics. No significant difference in its stability was observed between the two evaluated concentrations, solvents and light exposure (t95% between 25 and 30 h). Elevated temperature (30 °C) affected HSS stability and significantly reduced the t95% (4.6–6.3 h). HSS infusion solutions are physically and chemically stable (<5% degradation) for at least 6 h if stored below 30 °C. The in-use stability may be extended up to 24 h if stored below 24 °C.
Enhanced Adsorption of Methylene Blue by Chemically Modified Materials Derived from Phragmites australis Stems
Authors: Nguyet Bui Thi Minh , Nghi Nguyen Huu , Tien Nguyen Anh , Khieu Dinh Quang , Duc Ha Danh , Hung Nguyen Van
Published: December 2022

In this study, the biomass of Phragmites australis was chemically modified using NaOH and subsequently citric acid to produce an effective adsorbent named SA-RPB. The absorbent was characterized using XRD, SEM, BET, and FT-IR methods. The study’s findings indicated that the adsorbent existed mainly as cellulose crystals, contained micropores with an average diameter of 15.97 nm, and had a large number of hydroxyl and carboxyl groups on the surface. The adsorption process of SA-RPB was evaluated through the adsorption of methylene blue (MB) dye in aqueous solution. Adsorption kinetics showed that the pseudo-second-order model well described the adsorption process. The adsorption isotherm process satisfactorily fitted with the Langmuir model with the maximum adsorption capacity of 191.49 mg/g at 303 K. These findings show that MB may be efficiently removed from aqueous solutions using the adsorbent made from the raw biomass of Phragmites australis treated with NaOH and then citric acid.
Assessment of the Capability of Magnetic Nanoparticles to Recover Neodymium Ions from Aqueous Solution
Authors: Ambrož Ana , Ban Irena , Luxbacher Thomas
Published: December 2022

Magnetic nanoparticles (MNPs) have received increasing attention for various applications due to their fast synthesis, versatile functionalization, and recyclability by the application of a magnetic field. The high surface-to-volume ratio of MNP dispersions has suggested their use as an adsorbent for the removal of heavy metal ions. We investigated the applicability of MNPs composed of a maghemite core surrounded by a silica shell functionalized with aminopropylsilane, γ-Fe2O3-NH4OH@SiO2(APTMS), for the removal of neodymium ions (Nd3+) from aqueous solution. The MNPs were characterized for their size, composition, surface functionality and charge. Despite of the promising properties of MNPs, their removal from the aqueous dispersion with an external magnet was not sufficient to reliably quantify the adsorption of Nd3+ by UV-Vis spectroscopy.
Ionic Liquid Supported on Magnetic Graphene Oxide as a Highly Efficient and Stable Catalyst for the Synthesis of Triazolopyrimidines
Authors: Jahanbakhshi Azar , Farahi Mahnaz , Aghajani Yeganeh
Published: December 2022

A novel sulfonic acid functionalized ionic liquid was prepared by anchoring 1-(propyl-3-sulfonate) vinylimidazolium hydrogen sulfate ([(CH2)3SO3HVIm]HSO4) on Fe3O4@GO. The prepared heterogeneous catalyst was characterized by XRD, FT-IR, EDX, SEM, VSM and TGA techniques. The results show that [(CH2)3SO3HVIm]HSO4 was successfully deposited on the surface of Fe3O4@GO and the prepared ionic liquid catalyst exhibited good thermal stability. The activity of the prepared catalyst was investigated in the synthesis of triazolo[1,5-a]pyrimidine derivatives by a one-pot three-component reaction of active methylene compound (malononitrile or ethyl cyanoacetate), 3-amine-1H-1,2,4-triazole and aryl aldehydes under solvent-free conditions. This catalyst could be rapidly separated by an external magnet and recycled seven times without significant loss of catalytic activity.
ybrid Polymer Composite of Prussian Red Doped Polythiophene forAdsorptive Wastewater Treatment Application
Authors: Mustafa Mohd , Bashir Shabnum , Moosvi Bashir , Najar Mohd. Hanief , Masoodi Mubashir Hussain , Rizvi Masood Ahmad
Published: December 2022

Coordination compounds as dopants to conducting polymers combine desirable properties of individual components for a synergistic effect. Prussian red (PR) a low spin iron (III) coordination compound was doped in polythiophene (PTP) matrix to explore propensity of this inorganic-organic hybrid composite material towards wastewater treatment. PR doping was observed to improve mechano, thermal, electrical, and photocatalytic attributes of pure PTP. PTP/PR composite characterization was attempted using the powder X-ray diffraction, TEM, TGA, FTIR, BET analysis and UV-Visible spectroscopy. Optimization of adsorption conditions, adsorbent regeneration, adsorption thermodynamics studies of PTP/PR were carried out using malachite green (MG) dye as a model system. Under optimized conditions 92% MG dye adsorption was observed over 20 mg PTP/PR nanocomposite in 20 minutes at pH 7. PTP/PR nanocomposite also demonstrated a complimentary performance with real wastewater samples. Thermodynamic studies indicate spontaneous process with electrostatic attraction as the predominant noncovalent interaction. This study highlights designing catalysts capable of synergistic adsorption and photocatalytic activities for effective wastewater treatment.
Synthesis and Biological Evaluation of Some Hydrazide-Hydrazone Derivatives as Anticancer Agents
Authors: Akdağ Kadriye , Tok Fatih , Karakuş Sevgi , Erdoğan Ömer , Çevik Özge , Kaymakçıoğlu Bedia
Published: December 2022

In this study, a series of hydrazide-hydrazone derivatives (3a-3u) were synthesized and evaluated for their anticancer activitiesagainst prostate cancer cell line (PC-3), breast cancer cell line (MCF-7), colon cancer cell line (HT-29) and human umbilical vein endothelial cells (HUVEC) using MTT assay. In particular, compound 3h having a pyrrole ring was found to be the most potent derivative with IC50 = 1.32, 2.99, 1.71 μM against PC-3, MCF-7, HT-29 cancer cell lines respectively using paclitaxel as a standard compound. Furthermore, compound 3h was subjected to further biological studies such as caspase-3 activity and Annexin-V assay to evaluate their inhibitory potentials. The activity results displayed that compound 3h increased caspase-3 activation and the number of cells to early apoptosis. The additional studies like pharmacokinetics, bioavailability scores and drug-likeness properties were also evaluated. The in silico pharmacokinetics predictions displayed that the bioavailability of these compounds may be high.
Preparation and Characterization of NiCoFe2O4 Nanoparticles as an Effective Catalyst for the Synthesis of Trisubstituted Imidazole Derivatives Under Solvent-free Conditions
Authors: Hemmesi Leila
Published: December 2022

In this study, NiCoFe2O4 nanoparticles were prepared and used as a reactive catalyst for the synthesis of trisubstituted imidazoles. The multicomponent reactions of aromatic aldehydes, benzil and ammonium acetate were carried out under solvent-free and conventional heating conditions. In this reaction, some imidazole derivatives with high purity, short reaction times and high yields were obtained. The prepared nanocatalyst was characterized by FT-IR, XRD, EDX, VSM and SEM techniques. Moreover, the organic products were identified by melting point, FT-IR and 1H NMR analyzes.
Multicomponent Synthesis of Potentially Biologically Active Heterocycles Containing a Phosphonate or a Phosphine Oxide Moiety
Authors: Popovics-Tóth Nóra , Bálint Erika
Published: December 2022

Several multicomponent synthetic approaches were elaborated for plenty of novel nitrogen or oxygen heterocycles containing a phosphonate or a phosphine oxide moiety. All multicomponent reactions were optimized through a model reaction in respect of the heating mode, molar ratio of the starting materials, atmosphere, catalyst, temperature, reaction time and solvent applied, and then, the extended preparation of small libraries of structurally-related compounds was performed. Most of the reactions could be considered as “green syntheses”, as they were carried out in the absence of any catalyst and/or solvent using microwave (MW) irradiation or even at ambient temperature. The scaling-up of a MW-assisted synthesis was also elaborated in a continuous flow MW system. Altogether more than 150 heterocyclic organophosphorus compounds were synthesized, among them several derivatives showed moderate or promising activity against the HL-60 cell line and Bacillus subtilis bacteria.
Cost-Effective Control of Molecular Weight in Ultrasound-Assisted Emulsion Polymerization of Styrene
Authors: Korkut Ibrahim , Erden Fuat , Ozbay Salih
Published: December 2022

This paper focuses on the determination of economically most feasible conditions to obtain polystyrene with various target molecular weights through ultrasound-assisted emulsion polymerization. Briefly, batch polymerizations of styrene have been performed by ultrasound-assisted emulsion polymerization process using different reaction feed compositions. Polymerization rates were calculated using the monomer conversions at various reaction times. Also, molecular weights of the synthesized polymers, as well as the Mark-Houwink constants, were determined by intrinsic viscosity and gel permeation chromatography measurements. It was found that the polydispersity index of the polymers is ranging from 1.2 to 1.5, and the viscosity average molecular weights are in between 100000–1500000 g/mol depending on the reaction conditions. Finally, model equations were also developed for response variables, and the most economical ways of reaching various target molecular weights were interpreted by response surface methodology based multi objective optimization.
The Paramagnetic or Spin Crossover Iron(III) Complexes Based-on Pentadentate Schiff Base Ligand: Crystal Structure, and Magnetic Property Investigation
Authors: Xu, Zhijie , Meng Shuo , Cao Tong , Xin Yu , Zhang Mingjian , Duan Xiaoyi , Zhou Zhen , Zhang Daopeng
Published: December 2022

A series of bi- or mononuclear hexacoordinate iron(III) complexes, [Fe(L)][Fe(bpb)(CN)2]·CH3OH·0.5H2O (1), [Fe(L)] [Co(bpb)(CN)2]·CH3OH (2) [(Fe (L))2(4,4’-bipy)](BPh4)2 (3), [Fe(L)(py)](BPh4) (4) and [Fe(L)(dmap)](BPh4) (5) (bpb = 1,2-bis(pyridine-2-carboxamido)benzenate, L = N,N’-bis(2-hydroxybenzyliden)-1,7-diamino-4-azaheptane, dmap = 4-dimethylaminopyridine), have been prepared with the pentadentate Schiff base iron(III) compound as assemble precursor and characterized by element analysis, IR and X-ray diffraction. Single crystal structural determination revealed the neutral cyanide-bridged binuclear entity for complexes 1 and 2 and the cationic di- or mononuclear structure for complexes 3–5 with the positive charge(s) balanced by BPh4 – ion(s). The experimental study and theoretical simulation of the magnetic property discovered the ferromagnetic coupling between the Fe(III) ions bridged by cyanide group in complex 1 and the always high spin state of the Fe(III) ion coordinated to the Schiff base ligand in both complexes 1 and 2. The temperature dependent magnetic susceptibility investigation over complexes 3–5 showed the occurrence of the thermo-induced gradual complete spin crossover (SCO) property at about 115, 170 and 200 K, respectively.
Zinc(II) Complex Containing Oxazole Ring: Synthesis, Crystal Structure, Characterization, DFT Calculations, and Hirshfeld Surface Analysis
Authors: Karwan Omer Ali , Hikmat Ali Mohamad , Gerber Thomas , Hosten Eric
Published: December 2022

A new complex of Zn(II), with 5-chloro-2-methylbenzoxazole ligand (L), has been synthesized by the reaction of zinc dichloride with the ligand (L= C8H6ClNO) in ethanol solution: dichloridobis(5-chloro-2-methyl-1,3-benzoxazole)-zinc(II), C16H12Cl4N2O2Zn. The synthesized complex has been fully characterized by elemental analysis, molar conductivity, FT‑IR, UV‑Vis, and single-crystal X-ray diffraction (XRD). The XRD analysis reveals that the complex has a 1:2 metal-to-ligand ratio. The zinc(II) complex has a distorted tetrahedral geometry with two coordinated nitrogen atoms from the ligand. Density Functional Theory (DFT) calculations were performed at the B3LYP level of theory using the LANL2DZ basis set for metal complex and the 6–31G(d) basis set for non-metal elements to determine the optimum geometry structure of the complex, and the calculated HOMO and LUMO orbital energies were presented. A natural bond orbital (NBO) analysis was carried out on the molecules to analyze the atomic charge distribution before and after the complexation of the ligand. The Hirshfeld surface mapped over dnorm, shape index, and curvature exhibited strong H... Cl/Cl...H and H...H intermolecular interactions as the principal contributors to crystal packing.
Synthesis, Crystal Structures and Antibacterial Activities of N,N’-Ethylene-bis(3-bromosalicylaldimine) and Its Copper(II) and Cobalt(III) Complexes
Authors: Lin Xue-Song , Huang Yong-Gang , Jin Rui-Fa , Sang Ya-Li
Published: December 2022

A bis-Schiff base N,N’-ethylene-bis(3-bromosalicylaldimine) (H2L) was prepared from 3-bromosalicylaldehyde and ethane-1,2-diamine. With H2L as ligand, a new copper(II) complex [CuL] (1) and a new cobalt(III) complex [CoL(NCS) (DMF)] (2) were prepared and characterized by physico-chemical methods and single crystal X-ray analysis. X-ray analysis indicates that the Cu atom in complex 1 is in square planar coordination, and the Co atom in complex 2 is in octahedral coordination. The compounds were tested in vitro for their antibacterial activities on Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas fluorescens. Both complexes have effective activities on the bacteria.
Synthesis and In Vitro Cytotoxicity of Novel Halogenated Dihydropyrano[3,2-b]Chromene Derivatives
Authors: Sabouri Salehe , Faghih-Mirzaei Ehsan , Abaszadeh Mehdi
Published: December 2022

Lung and breast cancers are among the most common cancers. In the present work, initially, 6-bromo-; and 6-chloro-3-hydroxychromone compounds were prepared. In the next step, a series of 8-bromo-; and 8-chloro-dihyropyrano[3,2-b] chromene derivatives were synthesized by one-pot three component reaction of these two compounds, aromatic aldehydes, and ethyl cyanoacetate in the presence of triethylamine in EtOH at reflux conditions. The synthesized compounds were tested for their in vitro cytotoxic activity against A549 (lung cancer) and MCF-7 (breast cancer) cell lines. It was found that some compounds have high to moderate cytotoxicity, which makes them potential candidates for further studies. This study can be the basis for further studies to design and synthesis potent anticancer compounds and investigating their mechanism of action.
In vitro Assessment of Antiprotozoal and Antimicrobial Activities of Fractions and Isolated Compounds from Pallenis hierochuntica
Authors: Imieje Vincent O. , Falodun Abiodun , Zaki Ahmed A.
Published: December 2022

The antiprotozoal and antimicrobial properties of the extract and fractions of the whole plant of Pallenis hierochuntica were investigated against a panel of pathogenic organisms. Fractionation of the methanol extract of the whole plant of P. hierochuntica using reverse-phase chromatography gave 28 fractions and led to the isolation of 2 new bisabolone hydroperoxides, 6,10β,11-trihydroxybisabol-2-ene-1-one (1a), 6,10α,11-trihydroxybisabol-2-ene-1-one (1b) and also 6,10β-dihydroxybisabol-2,11-diene-1-one (2). They were characterised by extensive spectrometric analysis. Anti-infective investigations of the fractions revealed that fractions 22 to 26 possessed significant antimalarial activity against the D6 and W2 strains of Plasmodium falciparum with IC50 = 7.62–9.91 μg/mL and 5.49–6.08 μg/mL, respectively, and SI > 6.0 on average. Fractions 7, 16 to 24 exhibited good activity against Leishmania donovani promastigotes (IC50 = 6.71–18.77 μg/mL). Fractions 25 to 28 were active against Trypanosoma brucei trypomastigotes, fraction 25 being the most potent (IC50 = 4.13 μg/mL). Only fractions 11 to 13 were active against Aspergillus fumigatus (IC50 = 13.406 μg/mL). Compounds 1a and 2 were not promising against the organisms tested. 1a and 1b were characterised for the first time.
Adaptation of the Crystal Structure to the Confined Size of Mixed-oxide Nanoparticles
Authors: Makovec Darko
Published: December 2022

Chemical composition and crystal structure are central to defining the functional properties of materials. But when a material is prepared in the form of nanoparticles, the structure and, as a consequence, the composition will also frequently change. Understanding these changes in the crystal structure at the nanoscale is therefore essential not only for expanding fundamental knowledge, but also for designing novel nanostructures for diverse technological and medical applications. The changes can originate from two thermodynamically driven phenomena: (i) a crystal structure will adapt to the restricted size of the nanoparticles, and (ii) metastable structural polymorphs that form during the synthesis due to a lower nucleation barrier (compared to the equilibrium phase) can be stabilized at the nanoscale. The changes to the crystal structure at the nanoscale are especially pronounced for inorganic materials with a complex structure and composition, such as mixed oxides with a structure built from alternating layers of several structural blocks. In this article the complex structure of nanoparticles will be presented based on two examples of well-known and technologically important materials with layered structures: magnetic hexaferrites (BaFe12O19 and SrFe12O19) and ferroelectric Aurivillius layered-perovskite bismuth titanate (Bi4Ti3O12).
Syntheses, Crystal Structures and Xanthine Oxidase Inhibitory Activity of Aroylhydrazones
Authors: Han Yong-Jun
Published: December 2022

A series of hydrazones, (E)-N’-(4-hydroxy-3-methoxybenzylidene)-4-nitrobenzohydrazide (1), (E)-4-(dimethylamino)-N’-(4-hydroxy-3-methoxybenzylidene)benzohydrazide (2), N’-(2-hydroxy-5-methylbenzylidene)-4-nitrobenzohydrazide (3) and 2-fluoro-N’-(2-hydroxy-5-methylbenzylidene)benzohydrazide (4), were prepared and structurally characterized by elemental analysis, IR and 1H NMR spectra, and X-ray single crystal determination. The xanthine oxidase inhibitory activities of the compounds were investigated. Among the compounds, N’-(3-methoxybenzylidene)-4-nitrobenzohydrazide (1) showed the strongest activity. Docking simulations were performed to insert the compounds into the crystal structure of xanthine oxidase at the active site and to investigate the probable binding modes.
Trideset let delovanja Šole eksperimentalne kemije na Institutu »Jožef Stefan«: trideset let motiviranja mladih generacij in utrjevanja poti naravoslovnega izobraževanja
Authors: Tramšek Melita , Gruden Evelin , Jeran Marko
Published: December 2022

Pred 30. leti, natančneje spomladi leta 1992, je bila, v okviru Odseka za anorgansko kemijo in tehnologijo Instituta »Jožef Stefan«, ustanovljena Šola eksperimentalne kemije. Zaradi razvoja znanosti in interdisciplinarnih pristopov, je njen glavni namen približevanje kemije mladim generacijam in prikazovanje njene širše uporabe v vsakdanjem življenju. Šola eksperimentalne kemije tako ustvarja pomemben most med raziskovanjem in izobraževanjem ter aktivno prispeva k popularizaciji predmetnega področja v šolah.
Expansion-assisted iterative fluorescence in situ hybridization (EASI-FISH) in Drosophila CNS v1
Authors: Eddison Mark
Published: December 2022

A straightforward, robust, and reliable protocol (EASI-FISH) that utilizes expansion microscopy and the hybridization chain reaction for multiplexed in situ hybridization in thick slices of the mouse brain has recently been described (Wang et al., 2021). Below details a modified version of the EASI-FISH protocol for adult Drosophila CNS, which includes antibody detection of fluorescent reporters. The protocol also works well for larval CNS and is expected to be applicable to other tissue types.
Are retrospective assessments means of people’s experiences? Accounting for interpersonal and intrapersonal variability when comparing retrospective assessment data to ecological momentary assessment data.
Authors: Leertouwer IJsbrand , Schuurman Noémi K. , Vermunt Jeroen K.
Published: December 2022

Retrospective Assessment (RA) scores are often found to be higher than the mean of Ecological Momentary Assessment (EMA) scores about a concurrent period. This difference is generally interpreted as bias towards salient experiences in RA. During RA participants are often asked to summarize their experiences in unspecific terms, leaving room for personal interpretation. As a result, participants may use various strategies to summarize their experiences. In this study, we reanalyzed an existing dataset (N = 92) using a repeated N = 1 approach. We assessed for each participant whether it was likely that their RA score was an approximation of the mean of their experiences as captured by their EMA scores. We found considerable interpersonal differences in the difference between EMA scores and RA scores, as well as some extreme cases. Furthermore, for a considerable part of the sample (n = 46 for positive affect, n = 56 for negative affect), we did not reject the null hypothesis that their RA score represented the mean of their experiences as captured by their EMA scores. We conclude that in its current unspecific form RA may facilitate bias, although not for everyone. Future studies may determine whether differences between RA and EMA are mitigated using more specific forms of RA, while acknowledging interindividual differences.
Idiographic dynamics between suicide ideation and depression, anxiety and posttraumatic stress symptoms in persons living with HIV: A pilot study
Authors: Zhu Yiqin , Rodebaugh Thomas , Narine Kevin , Brown Lily A.
Published: December 2022

Background: Given that suicide ideation (SI) fluctuates drastically over short periods of time and is heterogenous across individuals, idiographic suicide research is warranted. In this pilot study, we used intensive ecological momentary assessment (EMA) to examine whether anxiety, depression, and PTSD symptoms on a given day predicted next-day SI on a person-to-person basis. Methods: PLWH (N = 10) with past-month SI completed daily randomly assessed ratings of suicidal urges using the Suicide-Visual Analogue Scale (S-VAS) and daily assessed ratings of anxiety, depression, and PTSD symptoms for 28 days. We used N = 1 Dynamic Structural Equation Modeling to test whether depression, anxiety or PTSD symptoms in the prior day predicted next-day S-VAS for each individual. Results: Across all participants, S-VAS on a given day was not predicted by prior-day anxiety, PTSD symptoms or S-VAS. In one participant, higher depression symptoms predicted lower next-day S-VAS. Conclusions: Daily-level data may be insufficient to predict near-term increases in suicide risk based on anxiety, depression, or PTSD symptoms in PLWH. These findings suggest the importance of finer-grained assessments (e.g., assessing suicide risk and its correlates multiple times per day) to better understand changes in suicide risk over time among PLWH.
Moving to Portugal: Conditions for Refugees’ Identity (Re)Configuration Processes
Authors: Sales Catarina , Novais Ivan , Ramos Deriscleia
Published: December 2022

This research seeks to explore how mobility interacts with identity (re)configuration processes. We take a comprehensive look at the impact of mobility on refugees’ adaptation of their own social identity in diasporas. To build our analytical standpoint, we will discuss theories of mobilities and identity studies and explore points of intersection between relational approaches to collective identities, theories of co-constitution of social formations, and mobile subjectivities and narratives about diasporans’ experiences, refugee hosting, and conditions for identity (re)configuration. Next, we apply our analytical perspective to a selection of existing empirical research on refugees in Portugal. We were able to identify some clues that indicate the relevance of our approach and suggest two lines for further empirical research in the Portuguese context.
Wear Rate Modelling and Analysis of Limestone Slurry Particulate Composites Using the Fuzzy Method
Authors: Lokanadham Dharmana , Sharma Rakesh Chandmal , Palli Srihari , Bhardawaj Sono
Published: December 2022

The present work is aimed at developing an Aluminium metal Matrix Composite (AMC) with an industrial waste Limestone Slurry Particulate (LSP) dust as reinforcement which is available in plenty at no cost. As the stone industry is producing huge amounts of dust as waste, utilization of this waste dust for producing useful materials can reduce its adverse effects on the environment. AMC with reinforced LSP composites are manufactured using stir casting process with varying weight% of LSP (0%, 4%, 8%, 12%, 16%). The particle size of LSP varied from 10-60 µm with an average size of 42 µm. The present work investigates the effect of control parameters on tribological properties (coefficient of friction and wear rate) of AMC reinforced with LSP. The development of suitable wear rate and coefficient of friction models using fuzzy logic is accomplished during this study.
An Efficient and Reliable Data Transmission Service using Network Coding Algorithms in Peer-to-Peer Network
Authors: Sable Nilesh P. , Rathod Vijay U. , Mahalle Parikshit N. , Railkar Poonam N.
Published: December 2022

Network coding is a progressive enhancement in natural network routing that increases throughput and reliability for unicast, multicast, and even broadcast transmissions. P2P networks are ideal for implementing network coding algorithms for two reasons: I. A P2P network's topology isn't predetermined. As a result, designing a topology that is compatible with the network coding algorithm is much easier. II. Every peer is an end host in this network.  As a result, instead of saving and sending the message, complex network coding operations, such as encoding and decoding, are now easier to perform. The objective of this work is to use the best features of network coding algorithms and properly apply them to P2P networks to create an efficient and reliable data transmission service. The goal of the network coding algorithm is to make better use of network resources and thus increase P2P network capacity. An encoding algorithm that enables an intermediate peer to produce output messages by encoding (that is, computing a function of the data it receives. The decoder's role is to obtain enough encoded packets so that the original information can be recovered. This research work has measured an amount of hypothetical and applied consequences in which the network coding procedure or a variation of it is used to improve performance parameters such as throughput and reliability in P2P network data transmission based on network coding. The comparison of data transmission between network routing and network coding algorithms was the main focus of this paper.  According to our simulations, the new network coding systems can reach 15% to 20% upper throughput than supplementary P2P network routing systems.
Policy-aware Distributed and Dynamic Trust based Access Control Scheme for Internet of Things
Authors: Railkar Poonam Ninad , Mahalle Parikshit Narendra , Shinde Gitanjali Rahul , Sable Nilesh P.
Published: December 2022

The use of smart devices is driving the Internet of Things (IoT) trend today. Day by day IoT helps to support more services like car services, healthcare services, home automation, and security services, weather prediction services, etc, to ease user’s life. Integration of heterogeneous IoT devices and social resources sometimes creates many problems like the privacy of data. To avoid privacy issues, an appropriate access control mechanism is required to check authorized and trusted devices, so that only valid devices can access the data which is only required.  In the sequel, this paper presents implementation of distributed and dynamic trust based access control mechanism (DDTAC) for secure machine to machine communication or distributed IoT environment. Novelty of this mechanism is that, it uses trust calculation and device classification for dynamic access control. The proposed scheme is implemented, tested and deployed on Node MCU and same mechanism is also simulated on NS-2 for large number of nodes. This access control model support Scalability, Heterogeneity, Privacy, Trust, Selective disclosure, Principle of least privileges, and lightweight calculation features. Results of this models proves that it gives good performance as compared to existing scheme in terms of scalability, throughput and delay. As number of devices increase it does not degrade performance. This mechanism is also protected against the Man-in-the-Middle attack, Sniffing attack, Session Hijacking attacks and Injection attacks. It required less time to detect and resist those attacks.
An Implementation of Divide and Conquer Clustering Technique for Improving the Interoperability in Hybrid Cloud Environment
Authors: Barhate Shweta
Published: December 2022

Cloud computing provides users with pool of resources ubiquitously on demand. While the resources are provided to the users, interoperability needs to be considered. Interoperability is the ability of the cloud environment to transfer the data internally or between the data centers seamlessly. Interoperability is the least studied issue in the field of cloud computing. This paper implements hybrid cloud as a solution to interoperability. Hybrid cloud is chosen for its powerful combination of high configured and secured private clouds and fast accessible and scalable public clouds. The interoperability is then proposed to be enhanced by implementing divide and conquer algorithm of clustering in hybrid cloud.
SCMBQA: Design of a Customised SCM-Aware Sidechaining Model for QoS Enhancement under Attack Scenarios
Authors: Shinkar Sonali V. , Thankachan Dolly
Published: December 2022

Storing& processing data for supply chain management (SCM) systems requires design of high-security and quality of service (QoS) aware models. These modelsassist in improving traceability performance of SCM deployments via integration of transparent & distributed mechanisms. A wide variety of security models are proposed by researchers to perform these tasks, and it is observed that blockchain-based SCM implementations outperform other models in terms of security & QoS metrics.But most of these implementationsare general-purpose and do not incorporate SCM-specific consensus & mining rules. It is also observed that, mining speed& throughput performance of these blockchain-based implementations reduces exponentially w.r.t. number of SCM transactions. To resolve these issues, this paper discusses design of a novel Proof-of-Supply Chain (PoSC) based consensus model, which is specifically designed for sidechain based SCM deployments. The PoSC consensus model is used for high-efficiency SCM-based data storage and communication scenarios. The proposed PoSC consensus model is capable of resisting selfish mining, time jacking, and sybil attacks, which are targeted towards SCM deployments. The model uses temporal performance metrics of miner nodes, and combines them with relationship graphs to form an SCM miner rank. Based on this rank, miner nodes are selected, and their consensus responses are recorded. These responses are processed using an augmented deep learning model, that is trained over 8 different SCM implementations via machine learning. After successful mining, responses obtained from these miners are used to incrementally train the machine learning model which assists in continuous performance improvement. The SCMBQA model was tested on milk supply chain, agriculture supply chain, and electronic supply chain applications, in terms of computational speed, throughput, energy requirement, retrieval & verification delay, and storage requirements. It was observed that the proposed PoSC consensus was capable of improving the computational speed by 8.5%, reduce energy consumption by 4.9%, improve throughput by 9.6%, and reduce storage costs by 15.4% when compared with standard blockchain-based SCM consensus models. This is because the proposed model deploys an intelligent sidechaining approach, that is capable of optimizing number of generated sidechains via temporal QoS & security performance metrics. Due to use of smaller chain lengths, the proposed model is capable of integrating privacy-aware & secure approaches depending upon different SCM stages. Thus, distributor-level security models are different than retailer-level security models, which assists in context-sensitive block deployments. Due to use of PoSC, the proposed model was observed to be 99.5% resilient against internal and external attacks, which makes it useful for real-time SCM deployments.
Evaluation of various MAC Protocols for Node Density in Wireless Sensor Networks based on QoS
Authors: Pulujkar Mosami , Kumar Sunil , Deshpande Vivek , Waghole Dattatray
Published: December 2022

A wireless sensor network is a collection of sensor nodes that communicate with one another to gather data and send it to a base station. The quality of service provided by sensor networks determines their efficiency and lifetime.  Energy, channel capacity, packet transmission, packet drop, and latency are all factors in QoS. In WSNs, routing protocols are designed to discover the shortest route to a network's destination, whereas MAC protocols are designed to transmit data through a communication channel. To increase the network's life span, the best routing and MAC protocols are required for communication. In this research, we examined the performance of different MAC protocols for a variety of QoS measures as node density increased. Future researchers will benefit from this research in establishing the best hybrid protocols for wireless sensor networks. The results demonstrate that CSMA is the best communication protocol among the others.
Classification Model for Meticulous Presaging of Heart Disease Detection through SDA and NCA using Machine learning :CMSDANCA
Authors: Aggarwal Ritu , Kumar Suneet
Published: December 2022

For the design and implementation of CDSS, computation time and prognostic accuracy are very important. To analyze the large collection of a dataset for detecting and diagnosis disease ML techniques are used. According to the reports of World Health Organizations, HD is a major cause of death and killer in urban and rural areas or worldwide. The main reason for this is a shortage of doctors and delay in the diagnosis. In this research work, heart disease is a diagnosis by the data mining techniques and used the clinical parameters of patients for early stages diagnosis. The intend of this learning to develop a representation that relies on the prediction method for coronary heart disease. This proposed work used the approach of self-diagnosis Algorithm, Fuzzy Artificial neural network, and NCA & PCA and imputation methods. By the use of this technique computation time for prediction of Coronary HD can be reduced. For the implementation of this the two datasets are using such as Cleveland and Statlog datasets that is collected from the UCI kaggle the ML repository. The datasets for the disease prediction measure are used to accurately calculate the difference between variables and to determine whether they are correlated or not. For this classification model, the performance measure is calculated in requisites of their accuracy, precision, recall, and specificity. This approach is evaluated on the heart disease datasets for improving the accuracy performance results obtained. The outcome for KNN+SDA+NCA+FuzzyANN for Cleveland dataset accuracy achieved 98.56 %.and for Statlog dataset 98.66 %..
EXPERIMENTAL TESTS TO ASSESS THE DYNAMIC CHARACTERISTICS OF WORM GEARBOXES
Authors:   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, SMERINGAIOVA ANNA , CORANIC TOMAS ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, HRABCAK MATEJ ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov
Published: December 2022

The article deals with the issue of experimental assessment of the dynamics of worm gears. The design of the methodology and the material and technical assurance of experimental tests to determine the impact of the use of various structural modifications on the dynamics of the worm gear are described. In the pilot part of the experiment, a gearbox was tested with an original design solution of bearing the worm wheel shaft in special damping inserts. The goal is to find ways to reduce the dynamic load of the most stressed components of the worm gear and increase their service life.
SpinBOT KIT THE NEW GENERATION OF ROBOTS – ANALYSIS OF OPERATING CHARACTERISTICS
Authors:   Spinbotics s.r.o., SMRCEK JURAJ , SMERINGAI PETER ,   Spinbotics s.r.o., SMERINGAIOVA ANNA ,   Technical University of Kosice, Faculty of Manufacturing Technologies with the seat in Presov
Published: December 2022

The reconfigurable robotic system SpinBOT Kit represents a new generation of robotic technology designed to solve the automation and robotization of production, non-production processes and service processes, with wide use in various sectors of industrial and non-industrial sectors and in municipal services. This paper presents an analysis of the parameters and characteristics of this reconfigurable robotic system. The system enables configuration of the robotic arm, manipulator or robotic peripherals with different kinematics and with different number of degrees of freedom.