Type Of Substitution Research Articles

Counterfactual Thinking and Attribute Substitution in Economic Behavior

This paper discusses how counterfactual thinking can be incorporated into behavioral economics by relating it to a type of attribution substitution involved in choices people make in conditions of Knightian uncertainty. It draws on Byrne’s ‘rational imagination’ account of counterfactual thinking, evidence from cognitive science regarding the forms it takes, and identifies types of attribution substitution specific to economic behavior. This approach, which elucidates the reflective stage of causal reasoning, is relevant for the explanation of hypothetical causal rules suitable for diverse tasks such as planning, expectations and mental simulations and for behavioural change interventions, which take into account people’s social and institutional embeddedness. The paper closes with a discussion of how this implies a specifically social Homo sapiens individual conception.

Substitution in Some Quranic Texts with Reference to their Realizations in English. A Syntactic and Lexical Study

The study deals with the relation of substitution, which is one of the constructional linguistic ties that contribute in textual cohesion by forming a textual net which helps interpreting and understanding the text. Substitution works at grammatical and lexical levels to achieve textual cohesion. Understanding the substituted items is achieved by returning to the previous ones. The problem is represented in finding substitutional expressions in the Qur'an texts and identifying their types as it is not an easy task for those who are not specialized with Arabic and Qur'anic studies as well as revealing to which extent they can achieve textual cohesion inside surah to avoid redundancy which resulted from repetition. This study aims at finding the role of substitution in the Qur'anic textual tying and achieving textual unity in order to enable readers to read the Glorious Qur'an and to facilitate its understanding for native and non-native speakers or readers and finding out the Qur'anic miracles, styles and systems through cohesive devices as well as knowing the way of textual building and cohesion. The study depends on two hypotheses which are: 1- substitution is a prominent device in cohesion which works at the grammatical and lexical levels and 2- the Glorious Qur'an has a variety of these devices which plays a vital role in tying texts in their surah grammatically and lexically to facilitate understanding without repetition. The adopted model in the study is Halliday and Hassan (1976) who suggest the types of substitution. The study depends on descriptive and analytical methodology which describes the ties of text that lead to consistency and cohesion.

On the crystal chemistry of sulfur-rich lazurite, ideally Na7Ca(Al6Si6O24)(SO4)(S3)–·nH2O

AbstractDark blue lazurite from the Malo-Bystrinskoe lazurite deposit, Baikal Lake area, Eastern Siberian region, Russia, was analyzed by electron microprobe and revealed an unusually high content of total sulfur corresponding to 8.3 wt% S. The relative content of sulfur in sulfate and sulfur in sulfide form was determined by wet chemical analysis. The H2O content was measured by means of differential thermal analysis in combination with mass spectrometry and infrared (IR) spectroscopy. The charge-balanced empirical formula of lazurite calculated on the basis of 12 (Al+Si) atoms per formula unit was (Na6.97Ca0.88K0.10)Σ7.96[(Al5.96Si6.04)Σ12O24](SO4)1.092−(S3−)0.55S0.052− Cl0.04·0.72H2O. The presence of H2O molecules and (S3)– and (SO4)2– groups was confirmed by the combination of IR, Raman, electron paramagnetic resonance (EPR), and X-ray photoelectron spectroscopy (XPS) methods. The idealized formula of lazurite is Na7Ca[Al6Si6O24](SO4)2–(S3)–·H2O, and it is believed that extra-framework cations and anions are grouped into clusters of [Na3Ca·SO4]3+ and [Na4(S3)–]3+. The types of isomorphous substitutions in nosean and haüyne are discussed. Lazurite is a clathrate-type mineral, which may be an effective (S3)– sensor due to the stability of the trisulfur radical anion in isolated cages of the crystal structure. This specific feature makes it possible to study the behavior of this ubiquitous radical anion over larger T and P ranges as compared to free species. This kind of lazurite, with oxidized and reduced sulfur species, seems to be appropriate for the estimation of the fugacity of SO2 and O2 in metasomatic systems forming lazurite-containing rocks. The systematic presence of incommensurate modulations is a unique structural feature of Baikal lazurite and may be an important marker indicating provenance of the mineral.

Cation-Substituted Na3SbS4 Electrolyte with High Sodium-Ion Conductivity

Solid electrolytes are key materials for developing all-solid-state rechargeable batteries. In particular, developing all-solid-state Na/S batteries is desired because of using abundant Na and S resources and their high energy density. To realize all-solid-state Na batteries, superior solid electrolytes with both high conductivity and good ductility are needed. Sulfide glass electrolytes are useful as a precursor for precipitating metastable crystalline phases which tend to have considerably high ionic conductivity [1]. We reported glass-ceramic electrolytes with cubic-Na3PS4 metastable phase having the conductivity of 10-4 S cm-1 [2]. Studies on increasing Na+ conductivity in sulfides have been widely done and Na3SbS4 [3] with higher Na+ conductivities of 10-3 S cm-1 have been developed. In particular, the Na3SbS4 electrolyte has an advantage of high safety in air atmosphere because of the formation of a hydrate with suppressing the generation of harmful H2S gas.In order to increase conductivity, cation-substituted Na3SbS4 electrolytes were focused on. The electrolytes were prepared via mechanochemistry, followed by heat-treatment to enhance their crystallinity. Two types of cation substitution were done; one is Na3-xSb1-xWxS4 in which a part of Sb was replaced by W (Na vacancy doping) and the other is Na3+ySb1-ySiyS4 in which a part of Sb was replaced by Si (additional Na doping). The structure and conductivity of the prepared electrolytes were evaluated. The prepared electrolytes were solid-solution based on Na3SbS4, and their conductivities were affected by the substituted elements and their contents. A partial substitution of Si for Sb decreased the conductivity, while W substitution increased the conductivity. The sulfide superionic conductor with the composition of Na2.88Sb0.88W0.12S4 exhibits a room temperature conductivity of 3.2 × 10−2 S cm−1 in a sintered body [4], which is higher than the best Li+ conductivity of 2.5 × 10−2 S cm−1 in LGPS-type Li9.54Si1.74P1.44S11.7Cl0.3 [5]. Partial substitution of Sb with W induced the generation of Na vacancies and tetragonal to cubic phase transition. The substitution of Mo instead of W also increased the conductivity of Na3SbS4, and thus Na vacancy doping is effective for increasing the conductivity of Na3SbS4.We applied the prepared sulfide electrolytes to all-solid-state Na/S batteries. For improving battery performance, the sulfur-carbon composites were prepared by melt-diffusion process of sulfur, and then the Na3SbS4 electrolyte was mixed to form sulfur composite positive electrodes. Na3Sb alloy was used as a negative electrode. Developed all-solid-state Na/S cells showed a full reversible capacity of 1560 mAh per gram of S and good cyclability at 25oC [6]. Acknowledgements: This work was supported by Element Strategy Initiative of MEXT, Grant Number JPMXP0112101003 and JSPS KAKENHI Grant Number 18H01713 and 19H05816.

Halogenated Terephthalic Acid "Antenna Effects" in Lanthanide-SURMOF Thin Films.

Lanthanide-based crystalline coatings have a great potential for energy-conversion devices, but until now luminescent surface-anchored materials were difficult to fabricate. Thin films, called lanthanides surface-mounted metal-organic frameworks (SURMOFs) with tetrasubstituted halide (fluorine, chlorine, and bromine) terephthalic acid derivative linkers as a basic platform for optical devices, exhibit a high quantum yield of fluorescence visible to the naked eyes under ambient light. We show that we can tune the luminescent properties in thin films by halide substitution, which affords control over the molecular structure of the material. We rationalize the mechanism for the modulation of the photophysical properties by "antenna effect", which controls the energy transfer and quantum yields using experimental and theoretical techniques for chelated lanthanides as a function of the type of atom substitutions at the phenyl rings and the resulting dihedral angle between phenyl rings in the linkers and carboxylate groups.

Study on structural growth behavior and simulated photoelectron spectroscopy of Sc2Sin(0,−1) (n ≤ 8) clusters using G4(MP2) theory

The lowest energy structures and of Sc2Sin (n ≤ 8) and their anions were probed with the high level of G4(MP2) methods. The most stable structures of Sc2Sin(0,−1) clusters were predicted to belong to the substitutional types in this work. The simulated PES of the negatively charged ions, especially for Sc2Si5−, had good correspondence with the experimental spectrogram. The little differences between the calculated and experimental AEAs and VDEs may indicate that the most stable structures for Sc2Sin clusters reported were reliable. Analysis of dissociation energies revealed that the species of Sc2Sin possessed higher stability than ScSin clusters. The Sc atoms acted as electron donors for neutral and anionic Sc2Sin (n = 1–5); however, silicon clusters act as electron donors for anionic Sc2Si6− and Sc2Si7−. The investigation of charge transfer has shown that the dipole moments were all been weakened when the neutral Sc2Sin clusters received an additional electron with the exception of Sc2Si3− and Sc2Si8−. The dipole moments were 0 D for neutral Sc2Si3, Sc2Si8 and anionic Sc2Si4−, which in turn caused the nonpolar result.

Deviation from Mendelian transmission of autosomal SNPs can be used to estimate germline mutations in humans exposed to ionizing radiation.

We aimed to estimate the rate of germline mutations in the offspring of individuals accidentally exposed to Cesium-137 ionizing radiation. The study included two distinct groups: one of cases, consisting of males and females accidentally exposed to low doses of ionizing radiation of Cs137, and a control group of non-exposed participants. The cases included 37 people representing 11 families and 15 children conceived after the accident. Exposed families incurred radiation absorbed doses in the range of 0.2 to 0.5 Gray. The control group included 15 families and 15 children also conceived after 1987 in Goiânia with no history of radiation exposure. DNA samples from peripheral blood were analyzed with the Affymetrix GeneChip® CytoScanHD™ to estimate point mutations in autosomal SNPs. A set of scripts previously developed was used to detect de novo mutations by comparing parent and offspring genotypes at the level of each SNP marker. Overall numbers of observed Mendelian deviations were statistically significant between the exposed and control groups. Our retrospective transgenerational DNA analysis showed a 44.0% increase in the burden of SNP mutations in the offspring of cases when compared to controls, based on the average of MFMD for the two groups. Parent-of-origin and type of nucleotide substitution were also inferred. This proved useful in a retrospective estimation of the rate of de novo germline mutations in a human population accidentally exposed to low doses of radiation from Cesium-137. Our results suggested that observed burden of germline mutations identified in offspring was a potentially useful biomarker of effect to estimate parental exposure to low doses of IR and could become an important marker suitable for biomonitoring human population exposed to environmental mutagens.

Introduction : Divided Memories, Shared Memories, Poland, Russia, Ukraine: History mirrored in Literature and Cinema


 
 
 In 2017, general-interest magazines illustrated the centenary of the Russian Revolution with stills from Eisenstein’s October [Октябрь] (1927). One strikingly showed soldiers rushing across a square to represent the storming of the Winter Palace by Bolshevik fighters on 7 November 1917. In reality, the actual assault was slow and even laborious. But for Western audiences, this film sequence has become an archive image, a piece of history. This type of substitution of artistic representation for historical reality conflicts with the positive construction of our knowledge of the past. Indeed, historians long refused to include literature and films in their historical research, as well as art in general, which has been mainly analysed from an aesthetic point of view.
 
 

Bacteriological Study and Investigation of Some Virulence Factors of Proteus mirabilis Bacteria Isolated from Urinary Tract Infection Patients in Ramadi City

Twenty isolates of Proteus mirabilis were diagnosed with 8.33% of the total of 240 samples that were isolatedfrom urinary tract infections of patients returning to Ramadi General Teaching Hospital and Women’s andChildren’s Hospital, after conducting biochemical tests and confirming them with VITEC 2, the results ofthe qualitative investigation of the UreR, ZapA, and MrpA genes showed that all isolates (20) of P. mirabilishad these three genes with a percentage of 100%. The results of the nitrogenous bases sequences confirmedthe agreement of the diagnostic results of P. mirabilis isolates with the isolates recorded in NCBI usingthe( MEGA7) program with 100% match for each of the MrpA gene isolation number( 17) and ZapA geneisolation number 12, as for the ZapA gene, isolation number (2), seven mutations of the type of equivalenttransition were shown, and one mutation, a type of non-equivalent substitution, transversion, with a matchratio of 98%, while for the UreR gene for isolates No.( 5 )and No.( 7), it showed four mutations equivalentto the same sites and for the same Sequence ID. With a similar ratio of 99%, it can be inferred in principlethat the ZapA, UreA, and MrpA genes were found in the same genus but in other species and strains with thesame sequence of nitrogenous bases.

Profile of genetic variations in severely calcified carotid plaques by whole-exome sequencing.

Background: The precise mechanisms of carotid calcification and its clinical significance have not been established.Methods: We classified ten plaques from carotid endarterectomy patients into high- and low-calcified plaques based on the Agatston calcium scores. We performed whole-exome sequencing for genetic profiles with single nucleotide variations (SNVs), insertions, and deletions. Bioinformatic data mining was then conducted to disclose specific gene variations to either high- or low-calcified carotid plaques.Results: In the carotid plaques, G:C>A:T/C:G>T:A transitions as SNVs, insT after C/insC after A as insertions, and delA after G/delT after C as deletions were most frequently observed, but no significant difference was observed between the high- and low-calcified plaque groups in their proportion of base-pair substitution types. In the bioinformatic analysis, SNVs of ATP binding cassette subfamily C member 6 (ADCC6) were more commonly found in high-calcified plaques and SNVs of KLKB1 were more commonly found in low-calcified plaques compared to the other group. No new genetic variants related to calcification or atherosclerosis among those not registered in dbSNP was detected.Conclusion: Our findings clarified the features of base-pair substitutions in carotid plaques, showing no relation to calcification. However, genetic variants in ADCC6 relating to vascular calcification for high-calcified plaques, and in KLKB1 encoding kallikrein associated with vascular regulation of atherosclerosis for low-calcified plaques were more specifically extracted. These results contribute to a better understanding of the genetic basis of molecular activity and calcium formation in carotid plaques.

QUASIBINAR SECTION OF AgGaS2-AgSbS2

The aim of this work is to study phase equilibrium and build a state diagram of the AgGaS2-AgSbS2 system. For research, the initial sulfides (AgGaS2 and AgSbS2) were synthesized from elements of high purity in quartz ampoules evacuated to 0.133 Pa. Quaternary alloys of the AgGaS2 – AgSbS2 systems were synthesized from ligatures at a temperature of 800–1300 K, depending on the composition. To homogenize the alloys, annealing was performed at 50–60 K below solidus for 300 h. Using complex methods of physicochemical analysis (differential thermal, X-ray phase, microstructural, microhardness measurement and density determination), phase equilibria in the AgGaS2-AgSbS2 system were studied. It was established that the AgGaS2-AgSbS2 system is a quasibinary section of the eutectic type and its state diagram is constructed. The coordinates of the eutectic correspond to 65 mol. % AgSbS2 and a temperature of 750 K. Based on the starting components in the section, the regions of solid solutions were determined. At room temperature, the regions of solid solutions based on AgGaS2 (8 mol. % AgSbS2) and based on AgSbS2 (14 mol. % AgGaS2) were revealed. At a eutectic temperature, solubility reaches 20 and 25 mol. %, respectively. According to the XRD data, α-solid solutions belong to monoclinic syngony, and with an increase in the concentration of AgGaS2, the lattice parameter increases (a = 12.861-12.972; b = 4.409-4.474; c = 13.282-13.324Å). AgSbS2 triple sulfide solid solutions crystallize in monoclinic syngony. These solid solutions are of the type of substitution. For structural and optical measurements, technological conditions for the growth of crystals of solid solutions were developed and their single crystals were grown. Single crystals of (AgSbS2)1-x(AgGaS2)x solid solutions were obtained by the Bridgman-Stockbarger method.

The effect of wood ash and styrofoam on the characteristics of AC-WC mixture

In this study, two types of substitutions, wood ash, and styrofoam, were used in asphalt concrete. The substitution of wood ash and styrofoam for asphalt concrete’s filler is expected to enrich the variations of the asphalt concrete material as well as to reduce the existing industrial waste. This study objective is to determine the effect of the asphalt mixture, which filler was substituted with the wood ash, on the Marshall test results. The initial stage of the research is to examine the physical properties of the asphalt and aggregate. Then, the optimum asphalt content (OAC) of the asphalt mixture was estimated. Then, the asphalt mixture’s filler was substituted with the wood ash and the asphalt material was substituted with the styrofoam. The result of this study is the best combination of the wood ash in asphalt mixture, which is 25% of the total filler, and the best combination of the styrofoam in asphalt mixture, which is 9% of the total asphalt content. With these best combinations of the wood ash and the styrofoam, the obtained Marshall stability of the asphalt concrete was 1,249.01 kg, which fulfills the ‘2018 Bina Marga’ requirement.

Nurses’ attitudes towards occupational transformation processes brought about by digital care technologies

Abstract Background. Digital technologies increasingly shape today’s world of work. This not only affects sectors such as knowledge work and the automotive industry, but also the care sector. On the one hand, many nurses today use technologies supporting some selected and rather peripheral nursing tasks (e.g., electronic documentation). However, on the other hand, more comprehensive and additionally proximal care-related task devices (e.g., diagnostics via telecare) seem to be used less often. From a psychological perspective, attitudes towards technology are an important antecedent of user behaviour. Therefore, in two studies we aimed to examine if nurses’ attitudes towards four digital technology fields (i.e., electronic documentation ED, ambient assisted living AAL, telecare application and robotics) are differing in relation to the type of task substitution, how technology appraisal and knowledge shape these attitudes, and how attitudes predict user behaviour. Method. We conducted two cross-sectional survey studies with German nurses (Study 1: N = 148, Study 2: N = 252) with well-established scales (i.e., general and work-related positive and negative attitudes towards technologies, ease of use, usability, knowledge, and technology use). Results. We found that it is important to consider positive and negative attitudes towards technology distinctively as intercorrelations were only moderately negative. As expected, we found in both studies that nurses reported stronger positive and less negative attitudes towards technologies assumed to be substituting more specific and peripheral (e.g., ED) than comprehensive and proximal care tasks (e.g., robotics). Moreover, we found that two types of technology appraisal (ease of use and usability) both positively correlated with positive attitudes towards all four technology fields, whereas patterns were more inconsistent and additionally influenced by technology knowledge when predicting negative attitudes. Although inconsistently across both studies and the considered technologies, in general, technology users reported more positive and less negative attitudes than non-users. Conclusion. If technology developers and nursing facility managers want to help nurses successfully adopting new technologies in their work routines, nurses’ technology appraisal and technology attitudes have to be considered already in the pre-development phase. Our study results show that nurses report different attitudes towards the four digital technology fields considered here in relation to the levels and types of task-substitution. More specifically, if core carerelated work-tasks (e.g., direct care) are not substituted, nurses report stronger positive and less negative attitudes towards the supporting technologies and higher user behaviour.

The mutant frequencies and types of mutations induced by Comfrey in the lungs of transgenic big blue rats

Comfrey (Symphytum Officinale) has been used as a vegetable and herbal remedy for many years. It, however, is a mutagen and carcinogen in liver and a possible genotoxin in lung. In order to evaluate the mutagenicity of comfrey and the mechanisms of action in rat lung, we examined the mutant frequencies (MF) and mutational types in the lung cII gene from transgenic Big Blue rats treated with 8% comfrey for 12 weeks. The CII MF in the lungs for rats fed with comfrey was 48 ± 9 × 10-6, which was significantly greater than the MF for control rats, 34 ± 10 × 10-6 (p = 0.026). The mutational spectrum in lung from comfrey-fed rats is significantly different from that in the control. G:C → T:A transversion (29%) was the major type of mutation in comfrey-fed rats, whereas G:C → A:T transition (63%) was the predominant mutation in the controls. An unusual type of tandem-base substitution (4%) was observed among the mutations from comfrey-fed rats that were not seen in the control. This type of tandem-base substitution has been suggested as a mutational signature for the genetic damage of pyrrolizidine alkaloids (PAs). The results indicate that comfrey is mutagenic in rat lung and the types of mutations induced by comfrey are similar to those by other PAs; and suggest that the mutagenicity of comfrey in rat lung results from the genotoxicity of PAs in the plant.

Mutation Patterns of Human SARS-CoV-2 and Bat RaTG13 Coronavirus Genomes Are Strongly Biased Towards C>U Transitions, Indicating Rapid Evolution in Their Hosts.

The pandemic caused by the spread of SARS-CoV-2 has led to considerable interest in its evolutionary origin and genome structure. Here, we analyzed mutation patterns in 34 human SARS-CoV-2 isolates and a closely related RaTG13 isolated from Rhinolophus affinis (a horseshoe bat). We also evaluated the CpG dinucleotide contents in SARS-CoV-2 and other human and animal coronavirus genomes. Out of 1136 single nucleotide variations (~4% divergence) between human SARS-CoV-2 and bat RaTG13, 682 (60%) can be attributed to C>U and U>C substitutions, far exceeding other types of substitutions. An accumulation of C>U mutations was also observed in SARS-CoV2 variants that arose within the human population. Globally, the C>U substitutions increased the frequency of codons for hydrophobic amino acids in SARS-CoV-2 peptides, while U>C substitutions decreased it. In contrast to most other coronaviruses, both SARS-CoV-2 and RaTG13 exhibited CpG depletion in their genomes. The data suggest that C-to-U conversion mediated by C deamination played a significant role in the evolution of the SARS-CoV-2 coronavirus. We hypothesize that the high frequency C>U transitions reflect virus adaptation processes in their hosts, and that SARS-CoV-2 could have been evolving for a relatively long period in humans following the transfer from animals before spreading worldwide.

The Use of Cohesive Devices in English Education Journal Articles Written by Graduate Students of UNNES

This study was a discourse analysis aimed to investigate the use of cohesive devices in English education journal articles written by graduate students of UNNES. The objectives of this study are to analyze cohesive devices in the article in order to explain the use of references in journal articles written by graduate students of UNNES, to analyze cohesive devices in the article in order to explain the use of substitutions in journal articles written by graduate students of UNNES, to analyze cohesive devices in the article in order to explain the use of ellipses in journal articles written by graduate students of UNNES, to analyze cohesive devices in the article in order to explain the use of conjunctions in journal articles written by graduate students of UNNES, to analyze cohesive devices in the article in order to explain the use of reiterations in journal articles written by graduate students of UNNES, to analyze cohesive devices in the article in order to explain the use of collocations in journal articles written by graduate students of UNNES. The objects of this research were English journal articles which are written by graduate students of UNNES. The 15 English education journal articles were analyzed using Halliday and Hasan’s (1976) theory. The results of this study showed that graduate students of UNNES used 6 types of cohesive devices, namely repetition, substitution, ellipsis, conjunction, reiteration, and collocation. References were more frequently than the other cohesive devices. On the other hand, the undergraduate students of UNNES rarely used substitution and ellipsis to achieve their writing.

The Single-Stranded RNA Bacteriophage Qβ Adapts Rapidly to High Temperatures: An Evolution Experiment.

Single-stranded (ss)RNA viruses are thought to evolve rapidly due to an inherently high mutation rate. However, it remains unclear how ssRNA viruses adapt to novel environments and/or how many and what types of substitutions are needed to facilitate this evolution. In this study, we followed the adaptation of the ssRNA bacteriophage Qβ using thermally adapted Escherichia coli as a host, which can efficiently grow at temperatures between 37.2 and 45.3 °C. This made it possible to evaluate Qβ adaptation to the highest known temperature that supports growth, 45.3 °C. We found that Qβ was capable of replication at this temperature; within 114 days (~1260 generations), we detected more than 34 novel point mutations in the genome of the thermally adapted Qβ population, representing 0.8% of the total Qβ genome. In addition, we returned the 45.3 °C-adapted Qβ populations to 37.2 °C and passaged them for 8 days (~124 generations). We found that the reverse-adapted Qβ population showed little to no decrease in fitness. These results indicate that Qβ can evolve in response to increasing temperatures in a short period of time with the accumulation of point mutations.

Magnetic susceptibility, XPS and NEXAFS spectroscopy of Ni-doped CaCu3Ti4O12 ceramics

Two series of Ni-doped CaCu3Ti4O12 ceramics with CaCu3Ti4-4хNi4хO12-δ and CaCu3-3хNi3хTi4O12 compositions were obtained by the solid-phase synthesis method. The magnetic behavior of the samples in the range of 77–400 K was studied by magnetic dilution. For the first time the samples of both series were characterized by the spectroscopic methods: XPS and NEXAFS. As a result of XPS spectroscopy, it was found that calcium, copper and nickel atoms mainly have the oxidation state (II), and titanium atoms can exhibit oxidation states of (III) and (IV). NEXAFS-study of Ni-doped CCTO showed that titanium atoms mainly have the oxidation state (IV). In the NEXAFS spectra of nickel of the both series of the samples, a feature associated with the presence of Ni(II) in the square-planar environment was manifested. It was concluded that nickel atoms were distributed in the positions of copper and titanium in the samples of both series. The magnetic behavior of the nickel-doped solid solutions of both types of substitution was different only at x ≥ 0.03, which indicated the advantage of placing nickel (II) atoms in the Cu(II) position. According to the magnetic dilution data, the antiferromagnetic exchange was realized between the nearest paramagnetic nickel atoms in CaCu3Ti4-4хNi4хO12-δ and the ferromagnetic one between the paramagnetic clusters.

English

PolyoxTM coagulant (molecular weight 5 × 106 Da) and hydroxypropyl methylcellulose (HPMC) K4M (USP substitution type 2208) were used to identify the composition variables that ensure the production of polyethylene oxide (PEO) matrix tablets with the same dissolution characteristics as those containing HPMC. Based on the dissolution results obtained using Apparatus 3, a 53% concentration of PEO polymer in the matrix tablet generates comparable drug release as matrix tablets containing 37% HPMC. During the dissolution test, several conditions simulating mechanical stresses in the gastrointestinal tract were investigated, in order to assess the robustness of the gel layer formed in selected PEO and HPMC matrix tablets. Increased mechanical stresses enhanced gel erosion from both matrix tablets evaluated and increased the drug release rate by approximately 10% regardless of the polymer type used. The HPMC gel layer formed was more resilient to mechanical stress and resulted in significantly slower drug release when compared to PEO matrix tablets with the same polymer concentration (37%). The research showed that gel robustness and the PEO polymer percolation threshold are dependent on the mechanical stresses applied. The percolation threshold changed from 30 to 37% when different mechanical stress was applied on Apparatus 2 and 3, respectively. The study revealed that the selection of in vitro dissolution method as well as polymer concentration is important for the evaluation of gel mechanical robustness. Key words: Polyethylene oxide (PEO), hydroxypropyl methylcellulose (HPMC), drug release, percolation threshold, matrix tablets. &nbsp

Evaluation of wheat flour substitution type (corn, green banana and rice flour) and concentration on local dough properties during bread baking

Different bread formulations, which provide different dough structures, were studied in order to better understand the effect of wheat flour substitution, flour type and concentration on dough development during baking, and their relationship with physical properties of the final product. Breads were produced with partial substitution of wheat flour by corn (CF), green banana (GF) and rice flour (RF), at different concentrations, and then baked at different times. Wheat flour substitution by CF, GF and RF in bread reduces heat transfer to the dough center by about 21%, 35% and 20%, respectively; and the water loss by about 5%, 15% and 0%, respectively. Those reductions were more influenced by flour type, than flour concentration. When wheat flour is substituted, the mechanisms of water migration are modified, once the pore system of bread dough is more discrete and stiffens later. Calculated thermal conductivity and diffusivity of the different flours used, and its correlations with average composite-bread heating rates (0.93) and water loss (0.85), respectively, indicates that thermal properties of composite bread dough could represent an important issue to be explored in dough systems with reduced gluten concentration.