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1.
Vet J ; 304: 106099, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38462168

RESUMO

The purpose of this study was to assess sedation, emesis and cardiovascular effects of dexmedetomidine alone or combined with acepromazine in healthy cats. Fourteen male cats aged 0.9 ± 0.5 years and weighing 3.7 ± 0.7 kg were randomly assigned to one of two experimental groups: GD, dexmedetomidine 5 µg/kg; and GDA, dexmedetomidine 5 µg/kg with acepromazine 0.03 mg/kg, all intramuscularly. Measurements were recorded at baseline, at 20 minutes and then at 10-minute intervals following sedation and included heart rate (HR), respiratory rate (FR), systolic arterial pressure (SAP), rectal temperature (RT), number of episodes of emesis and sedation score (0-4). Data were compared using ANOVA for repeated measures followed by Sídák and Dunnet test. Sedation scores were compared between groups at T20 using Mann-Whitney test. Significance was considered when P <0.05. At T20, HR was significantly lower in GDA (99 ± 14 beats/min) compared with GD (133 ± 19 beats/min) and SAP was significantly lower in both groups compared with baseline (126 ± 14 vs. 148 ± 26 and 111 ± 13 vs. 144 ± 17 mmHg in GD and GDA, respectively). Duration of sedation was similar between groups, although sedation scores differed significantly at T20, with 1 (0-4) in GD and 4 (4-4) in GDA. More episodes of emesis were recorded in GD compared with GDA. The combination of dexmedetomidine and acepromazine produced more profound sedation with faster onset and lower incidence of emesis compared with dexmedetomidine alone in healthy cats.


Assuntos
Anestesia , Dexmedetomidina , Gatos , Masculino , Animais , Hipnóticos e Sedativos/farmacologia , Acepromazina/farmacologia , Dexmedetomidina/farmacologia , Anestesia/veterinária , Vômito/veterinária
2.
J Dent Res ; 103(1): 71-80, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37982164

RESUMO

The regeneration of periodontal, periapical, and pulpal tissues is a complex process requiring the direct involvement of cells derived from pluripotent stem cells in the periodontal ligament and dental pulp. Dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs) are spatially distinct with the potential to differentiate into similar functional and phenotypic cells. We aimed to identify the cell heterogeneity of DPSCs and PDLSCs and explore the differentiation potentials of their specialized organ-specific functions using single-cell transcriptomic analysis. Our results revealed 7 distinct clusters, with cluster 3 showing the highest potential for differentiation. Clusters 0 to 2 displayed features similar to fibroblasts. The trajectory route of the cell state transition from cluster 3 to clusters 0, 1, and 2 indicated the distinct nature of cell differentiation. PDLSCs had a higher proportion of cells (78.6%) at the G1 phase, while DPSCs had a higher proportion of cells at the S and G2/M phases (36.1%), mirroring the lower cell proliferation capacity of PDLSCs than DPSCs. Our study suggested the heterogeneity of stemness across PDLSCs and DPSCs, the similarities of these 2 stem cell compartments to be potentially integrated for regenerative strategies, and the distinct features between them potentially particularized for organ-specific functions of the dental pulp and periodontal ligament for a targeted regenerative dental tissue repair and other regeneration therapies.


Assuntos
Polpa Dentária , Ligamento Periodontal , Células Cultivadas , Células-Tronco , Diferenciação Celular , Proliferação de Células , Perfilação da Expressão Gênica , Osteogênese/fisiologia
5.
Phys Rev E ; 108(1-1): 014308, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37583232

RESUMO

We discuss the majority vote model coupled with scale-free networks and investigate its critical behavior. Previous studies point to a nonuniversal behavior of the majority vote model, where the critical exponents depend on the connectivity. At the same time, the effective dimension D_{eff} is unity for a degree distribution exponent 5/2<γ<7/2. We introduce a finite-size theory of the majority vote model for uncorrelated networks and present generalized scaling relations with good agreement with Monte Carlo simulation results. Our finite-size approach has two sources of size dependence: an external field representing the influence of the mass media on consensus formation and the scale-free network cutoff. The critical exponents are nonuniversal, dependent on the degree distribution exponent, precisely when 5/2<γ<7/2. For γ≥7/2, the model is in the same universality class as the majority vote model on Erdos-Rényi random graphs. However, for γ=7/2, the critical behavior includes additional logarithmic corrections.

6.
Chemosphere ; 308(Pt 3): 136569, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36155023

RESUMO

Green turtles, Chelonia mydas, have been included in biomonitoring efforts given its status as an endangered species. Many studies, however, rely on samples from stranded animals, raising the question of how death affects important biochemical and molecular biomarkers. The goal of this study was to investigate post mortem fluctuations in the antioxidant response and metabolism of carbohydrates in the liver of C. mydas. Liver samples were obtained from six green turtles which were submitted to rehabilitation and euthanized due to the impossibility of recovery. Samples were collected immediately after death (t = 0) and at various time intervals (1, 2, 3, 4, 5, 6, 12, 18 and 24 h post mortem), frozen in liquid nitrogen and stored at -80 °C. The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH) were analyzed, as were the levels of lipid peroxidation, glycogen concentration, RNA integrity (RNA IQ) and transcript levels of carbonic anhydrase and pyruvate carboxylase genes. Comparison between post mortem intervals showed a temporal stability for all the biomarkers evaluated, suggesting that changes in biochemical and molecular parameters following green turtle death are not immediate, and metabolism may remain somewhat unaltered up to 24 h after death. Such stability may be associated with the overall lower metabolism of turtles, especially under an oxygen deprivation scenario such as organismal death. Overall, this study supports the use of biomarkers in sea turtles sampled within a period of 24 h post mortem for biomonitoring purposes, though it is recommended that post mortem fluctuations of particular biomarkers be evaluated prior to their application, given that proteins may show varying degrees of susceptibility to proteolysis.


Assuntos
Anidrases Carbônicas , Tartarugas , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Anidrases Carbônicas/metabolismo , Catalase/metabolismo , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glicogênio/metabolismo , Nitrogênio/metabolismo , Oxigênio/metabolismo , Piruvato Carboxilase/metabolismo , RNA/metabolismo , Tartarugas/metabolismo
7.
Braz J Biol ; 84: e260985, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35674589

RESUMO

The search for more environmental friendly herbicides, aiming at the control of agricultural pests, combinated with less harmfulness to human health and the environment has grown. An alternative used by researchers is the application of products of secondary plant metabolism, which are investigated due to their potential bioactivities. Thus, species belonging to the Myrtaceae family are potential in these studies, since this family is recognized for having high biological activity. A species belonging to this genus is Psidium cattleyanum, which has a medicinal effect and its fruits are used in human food. Thus, the objective of this research was to evaluate and compare the phyto-cyto-genotoxicity of aqueous and ethanolic leaf extracts of the specie P. cattleyanum, from plant bioassays, as well as to identify the main classes of compounds present in the extracts. For this, the extracts were prepared, characterized and biological tests were carried out by evaluating, in seeds and seedlings of lettuce and sorghum, the variables: percentage of germination, germination speed index, root growth and aerial growth; and in meristematic lettuce cells the variables: mitotic phases, mitotic index, nuclear alterations and chromosomal alterations. Flavones, flavonones, flavonols, flavononols, flavonoids, alkaloids, resins, xanthones and anthraquinone glycoside were characterized in the ethanolic extract. Both evaluated extracts, in the highest concentration, inhibited the initial plant development. All treatments caused alterations in the mitotic phases and inhibited mitotic index. In addition, the treatments promoted an increase in nuclear and chromosomal alterations. The mechanism of action presented was aneugenic, clastogenic and determined in epigenetic alterations. The ethanolic extract was more cytotoxic, since it had a more expressive effect at a lower concentration. Despite the cytotoxicity of the extracts under study, they promoted alterations at lower levels than the glyphosate positive control.


Assuntos
Alcaloides , Psidium , Bioensaio , Análise Citogenética , Humanos , Extratos Vegetais/toxicidade , Folhas de Planta
8.
Phys Rev E ; 105(3-1): 034105, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35428121

RESUMO

We define a stochastic reaction-diffusion process that describes a consensus formation in a nonsedentary population. The process is a diffusive version of the majority-vote model, where the state update follows two stages: In the first stage, spins are allowed to jump to a random neighbor node with probabilities D_{+} and D_{-} for the respective spin orientations, and in the second stage, the spins in the same node can change its values according to the majority-vote update rule. The model presents a consensus formation phase when the concentration is greater than a threshold value and a paramagnetic phase on the converse for equal diffusion probabilities, i.e., maintaining the inversion symmetry. Setting unequal diffusion probabilities for the respective spin orientations is the same as applying an external magnetic field. The system undergoes a discontinuous phase transition for concentrations higher than the critical threshold on the external field. The individuals that diffuse more dominate the stationary collective opinion.

9.
Sci Rep ; 12(1): 4392, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35293387

RESUMO

Giant seafloor craters are known along many a continental margin with recurrent mass-wasting deposits. However, the impact of breakup-related magmatism on the evolution of such craters is barely understood. Using high-quality geophysical datasets, this work examines the genetic relationship among the location of magmatic sills, forced folds and the formation of giant paleo-seafloor craters underneath an ancient mass-transport complex in the Møre and Vøring basins, offshore Norway. The data reveal that forced folding of near-seafloor strata occurred because of the intrusion of several interconnected magmatic sills. Estimates of 1-dimensional uplift based on well data show that uplift occurred due to the intrusion of magma in Upper Cretaceous to Lower Eocene strata. Our findings also prove that subsurface fluid plumbing associated with the magmatic sills was prolonged in time and led to the development of several vertical fluid flow conduits, some of which triggered mass wasting in Neogene to Recent times. The repeated vertical expulsion of subsurface fluids weakened the strata on the continental slope, thereby promoting mass wasting, the selective cannibalization of the paleo-seafloor, and the formation of elongated craters at the basal shear zone of the mass-transport complex. Significantly, the model presented here proves a close link between subsurface magmatic plumbing systems and mass wasting on continental margins.


Assuntos
Fenômenos Geológicos , Erupções Vulcânicas , Noruega
11.
J Nutr Health Aging ; 25(7): 889-894, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34409967

RESUMO

OBJECTIVES: Significant weight loss and/or loss of appetite is a criterion of a depressive episode. While malnutrition is associated with many adverse health outcomes, the impact of malnutrition in late-life depression has hardly been examined. The present study aims to (1) evaluate the prevalence of malnutrition in depressed older inpatients, and (2) whether and which indices of malnutrition predict adverse health outcomes in late-life depression. DESIGN: A prospective study at 6 months follow-up. SETTING: A University-based psychiatric hospital. PARTICIPANTS: 105 older adults (psychiatric inpatients suffering from unipolar MDD). MEASUREMENTS: Participants were evaluated according the Mini Nutritional Assessment (MNA) and anthropometric measures to assess their nutritional status. Multiple regression analyses were used to evaluate the association between the MNA score as well as anthropometric measures with either falls or rehospitalization for any reason. RESULTS: Based on the MNA score, 78 (74.3%) patients were at risk of malnutrition and 13 (12.4%) actually presented malnutrition. Malnutrition was associated with a higher age, frailty, lower body mass index, and smaller calf circumference. During follow-up, 21 (20%) patients fell, 27 (25.7%) were rehospitalized, and 3 died (2.9%). The MNA score was associated with adverse health outcomes, but a low calf circumference predicted falling (OR 4.93 [95% CI: 1.42-17.2], p=.012) and a higher calf circumference rehospitalization (OR 1.17 [95% CI: 1.01-1.35], p=.032). CONCLUSION: Malnutrition is prevalent in older depressed inpatients. In contrast to subjective proxies for malnutrition, which are common in depression, only objective measures of malnutrition predict adverse health outcomes such as falls and rehospitalization.


Assuntos
Transtorno Depressivo Maior , Avaliação Geriátrica , Desnutrição , Avaliação Nutricional , Estado Nutricional , Idoso , Idoso de 80 Anos ou mais , Anorexia/etiologia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Pacientes Internados , Masculino , Desnutrição/diagnóstico , Desnutrição/etiologia , Desnutrição/psicologia , Pessoa de Meia-Idade , Estudos Prospectivos , Redução de Peso
12.
Horm Metab Res ; 53(3): 204-206, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33652492

RESUMO

Currently, we are experiencing a true pandemic of a communicable disease by the virus SARS-CoV-2 holding the whole world firmly in its grasp. Amazingly and unfortunately, this virus uses a metabolic and endocrine pathway via ACE2 to enter our cells causing damage and disease. Our international research training programme funded by the German Research Foundation has a clear mission to train the best students wherever they may come from to learn to tackle the enormous challenges of diabetes and its complications for our society. A modern training programme in diabetes and metabolism does not only involve a thorough understanding of classical physiology, biology and clinical diabetology but has to bring together an interdisciplinary team. With the arrival of the coronavirus pandemic, this prestigious and unique metabolic training programme is facing new challenges but also new opportunities. The consortium of the training programme has recognized early on the need for a guidance and for practical recommendations to cope with the COVID-19 pandemic for the community of patients with metabolic disease, obesity and diabetes. This involves the optimal management from surgical obesity programmes to medications and insulin replacement. We also established a global registry analyzing the dimension and role of metabolic disease including new onset diabetes potentially triggered by the virus. We have involved experts of infectious disease and virology to our faculty with this metabolic training programme to offer the full breadth and scope of expertise needed to meet these scientific challenges. We have all learned that this pandemic does not respect or heed any national borders and that we have to work together as a global community. We believe that this transCampus metabolic training programme provides a prime example how an international team of established experts in the field of metabolism can work together with students from all over the world to address a new pandemic.


Assuntos
COVID-19 , Diabetes Mellitus , Educação Médica Continuada , Obesidade , Pandemias , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/terapia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Humanos , Obesidade/epidemiologia , Obesidade/terapia
13.
J Proteomics ; 239: 104181, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33677101

RESUMO

Gluten proteins contribute to the rheological properties of dough. Mass spectrometric techniques help to understand the contribution of these proteins to the quality of the end product. This work aimed to apply modern proteomic techniques to characterize and provide a better understanding of gluten proteins in wheat flours of different technological qualities. Nine Brazilian wheat flours (Triticum aestivum) classified by rheological gluten force were used to extract the proteins. Extracts were pooled together by technological qualities in low (LW), medium (MD), and superior (SP). Peptides were analyzed by nanoUPLC and mass spectrometry multiplex method (MSE). Collectively, 3545 peptides and 1297 proteins were identified, and 116 proteins were found differentially abundant. Low molecular weight glutenin subunits (LMW-GS) were found up-regulated only in SP samples. Proteins related to wheat grain hardness, such as puroindoline-A, were found in significant concentration in LW samples. After domain prediction, LW presented a different pattern with a lower abundance of functional domains, and SP presented chaperones, known to be involved in adequate folding of the storage proteins. NanoUPLC-MSE was efficient in analyzing and distinguishing the proteomic pattern of wheat flours from different qualities, pointing out the differentially abundant gluten proteins and providing a better understanding of wheat flour quality. SIGNIFICANCE: Common wheat is one of the most important staple food sources in the world. The improvement and comprehension of wheat quality has been a major objective of plant breeders and cereal chemists. Our findings highlighted the application of a modern proteomic approach to obtain a better understanding of the impact of gluten proteins on the technological quality of different wheat flours. The obtained data revealed different abundances of wheat quality-related proteins in superior quality flours when compared with samples of low rheological properties. In addition, multivariate statistical analysis clearly distinguished the flours of different qualities. This work contributes to the consolidation of research in the field of wheat technological quality.


Assuntos
Farinha , Triticum , Brasil , Pão , Glutens , Proteômica
14.
Top Companion Anim Med ; 41: 100459, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32823158

RESUMO

A pregnant 2-year-old mixed-breed dog was admitted with a 2-day history of lethargy, anorexia and painful abdominal distension. Clinical manifestations were unspecific and mainly suggested hypovolemic shock. Physical examination, ultrasonographic evaluation and radiographs confirmed mid-late pregnancy and evident signs of fetal death and peritoneal effusion. An exploratory laparotomy was immediately initiated which revealed torsion of the right gravid uterine horn over the left one and, simultaneously, the unexpected presence of splenic torsion and rupture, with a stretched omentum covering and exerting tension on the spleen's cranial pole. Histopathology revealed hemorrhagic infarction of the uterus and spleen. The animal recovered uneventfully and was later submitted to a preventive gastropexy.


Assuntos
Doenças do Cão/diagnóstico , Esplenopatias/veterinária , Anormalidade Torcional/veterinária , Doenças Uterinas/veterinária , Animais , Cães , Feminino , Morte Fetal , Laparotomia/veterinária , Gravidez
15.
Animal ; 14(S3): s427-s437, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32829724

RESUMO

The production of beef cattle in the Atlantic Forest biome mostly takes place in pastoral production systems. There are millions of hectares covered with pastures in this biome, including degraded pasture (DP), and only small area of the original Atlantic Forest has been preserved in tropics, implying that actions must be taken by the livestock sector to improve sustainability. Intensification makes it possible to produce the same amount, or more beef, in a smaller area; however, the environmental impacts must be assessed. Regarding climate change, the C dynamics is essential to define which beef cattle systems are sustainable. The objectives of this study were to investigate the C balance (t CO2e./ha per year), the intensity of C emission (kg CO2e./kg BW or carcass) and the C footprint (t CO2e./ha per year) of pasture-based beef cattle production systems, inside the farm gate and considering the inputs. The results were used to calculate the number of trees to be planted in beef cattle production systems to mitigate greenhouse gas (GHG) emissions. The GHG emission and C balance, for 2 years, were calculated based on the global warming potential (GWP) of AR4 and GWP of AR5. Forty-eight steers were allotted to four grazing systems: DP, irrigated high stocking rate pasture (IHS), rainfed high stocking rate pasture (RHS) and rainfed medium stocking rate pasture (RMS). The rainfed systems (RHS and RMS) presented the lowest C footprints (-1.22 and 0.45 t CO2e./ha per year, respectively), with C credits to RMS when using the GWP of AR4. The IHS system showed less favorable results for C footprint (-15.71 t CO2e./ha per year), but results were better when emissions were expressed in relation to the annual BW gain (-10.21 kg CO2e./kg BW) because of its higher yield. Although the DP system had an intermediate result for C footprint (-6.23 t CO2e./ha per year), the result was the worst (-30.21 CO2e./kg BW) when the index was expressed in relation to the annual BW gain, because in addition to GHG emissions from the animals in the system there were also losses in the annual rate of C sequestration. Notably, the intensification in pasture management had a land-saving effect (3.63 ha for IHS, 1.90 for RHS and 1.19 for RMS), contributing to the preservation of the tropical forest.


Assuntos
Pegada de Carbono , Fazendas , Gases de Efeito Estufa , Criação de Animais Domésticos , Animais , Bovinos , Ecossistema , Florestas , Efeito Estufa
16.
Environ Monit Assess ; 190(6): 329, 2018 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-29730718

RESUMO

This study evaluated an 8-year dataset (2007 to 2015, except 2008) in the attempt to identify the most susceptible periods for the occurrence of diarrheic shellfish poisoning (DSP) episodes associated with the presence of toxigenic dinoflagellates, Dinophysis spp., in the mussel farming area of Babitonga Bay (southern Brazil). Dinophysis acuminata complex was the most frequent (present in 66% of the samples) and abundant (max. 4100 cells L-1) taxon, followed by D. caudata (14%; max. 640 cells L-1) and D. tripos (0.9%; max. 50 cells L-1). There was a marked onset of the annual rise in Dinophysis spp. abundance during weeks 21-25 (early winter) of each year, followed by a second peak on week 35 (spring). Mussel (Perna perna) samples usually started testing positive in DSP mouse bioassays (MBA) in late winter. Positive results were more frequent in 2007 and 2011 when the mean D. acuminata complex abundance was ~ 500 cells L-1. Although positive DSP-MBA results were observed in only 11% of the samples during the studied period, the toxin okadaic acid (OA) was present in 90% of the analyzed mussels (max. 264 µg kg-1). MBA results were positive when D. acuminata complex cell densities exceed 1200 ± 300 cells L-1, while trace toxin amounts could be detected at cell densities as low as 150 ± 50 cells L-1 (free OA) to 200 ± 100 cells L-1 (conjugated OA). Low salinity and the meteorological conditions triggered by La Niña events were the main factors associated with both Dinophysis abundance and OA accumulation in mussels.


Assuntos
Aquicultura , Monitoramento Ambiental , Estuários , Toxinas Marinhas/metabolismo , Perna (Organismo)/fisiologia , Poluentes Químicos da Água/metabolismo , Animais , Bivalves , Brasil , Dinoflagellida , Toxinas Marinhas/análise , Camundongos , Alimentos Marinhos , Estações do Ano , Frutos do Mar/análise , Intoxicação por Frutos do Mar , Poluentes Químicos da Água/análise
17.
Carbohydr Polym ; 190: 339-345, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29628256

RESUMO

Mucoadhesive membranes were proposed in this study as drug delivery system for betamethasone-17-valerate (BMV) in the treatment of recurrent aphthous stomatitis (RAS). The membranes were obtained by using the polymers chitosan (CHI) in both presence and absence of polyvinilpyrrolidone (PVP), following the solvent evaporation method. The presence of PVP in the membranes causes significant modifications in its thermal properties. Changes in the thermal events at 114 and 193 °C (related to BMV melting point), and losses in mass (39.38 and 30.68% for CH:PVP and CH:PVP-B, respectively), suggests the incorporation of BMV in these membranes. However, the morphological aspects of the membranes do not change after adding PVP and BMV. PVP causes changes in swelling ratios (>80%) of the membranes, and it is suggested that the reorganization of the polymer mesh was highlighted by the chemical interactions between the polymers leading to different percentages of BMV released ∼40% and ∼80% from CH-B and CH:PVP-B. BMV release profile follows Korsmeyer and Peppas model (n > 0.89) which suggests that the diffusion of the drug in the swollen matrix is driven by polymer relaxation. In addition, the membranes containing PVP (higher swelling ability) present high rates of tensile strength, and therefore, higher mucoadhesion. Moreover, given the results presented, the developed mucoadhesive membranes are a promising system to deliver BMV for the treatment of RAS.

18.
Phys Rev E ; 97(2-2): 029901, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29548199

RESUMO

This corrects the article DOI: 10.1103/PhysRevE.93.042111.

19.
Phys Chem Chem Phys ; 19(25): 16395-16405, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28627529

RESUMO

In this study we investigated the structural, optical band-gap, and magnetic properties of CoYxFe2-xO4 (0 ≤ x ≤ 0.04) nanoparticles (NPs) synthesized using a combustion reaction method without the need for subsequent heat treatment or the calcing process. The particle size measured from X-ray diffraction (XRD) patterns and transmission electron microscope (TEM) images confirms the nanostructural character in the range of 16-36 nm. The optical band-gap (Eg) values increase with the Y3+ ion (x) concentration being 3.30 and 3.58 eV for x = 0 and x = 0.04, respectively. The presence of yttrium in the cobalt ferrite (Y-doped cobalt ferrite) structure affects the magnetic properties. For instance, the saturation magnetization, Ms and remanent magnetization, Mr, decrease from 69 emu g-1 to 33 and 28 to 12 emu g-1 for x = 0 and x = 0.04, respectively. On the other hand the coercivity, Hc, increases from 1100 to 1900 Oe for x = 0 and x = 0.04 at room temperature. Also we found that Ms, Mr, and Hc decreased with increasing temperature up to 773 K. The cubic magnetocrystalline constant, K1, determined by using the "law of approach" (LA) to saturation decreases with Y3+ ion concentration and temperature. K1 values for x = 0 (x = 0.04) were 3.3 × 106 erg cm-3 (2.0 × 106 erg cm-3) and 0.4 × 106 erg cm-3 (0.3 × 106 erg cm-3) at 300 K and 773 K, respectively. The results were discussed in terms of inter-particle interactions induced by thermal fluctuations, and Co2+ ion distribution over tetrahedral A-sites and octahedral B-sites of the spinel structure due to Y3+ ion substitution.

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