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The purpose of this paper is to synthesize the manganese ferrite nanoparticle MnFe₂O₄ and to investigate the structure, size and to study the electronic and the magnetic properties of MnFe₂O₄ nanoparticles.

The co-precipitation method is used to synthesize the MnFe₂O₄. The structure and size were investigated by X-ray diffraction. The superconducting quantum interference device is used to determine the some magnetic ground. From theoretical investigation point of view self-consistent ab initio calculations, based on density functional theory approach using full potential linear augmented plane wave method, were performed to investigate both electronic and magnetic properties of the MnFe₂O₄. The high temperatures series expansion (HTSE) is used to study the magnetic properties of MnFe₂O₄.

The saturation magnetization, the coercivity and the transition temperature varied between 21-43 emu/g, 20-50 Oe and 571-630 K, respectively, have been studied. The gap energy of MnFe₂O₄ has been deduced. The critical temperature and the critical exponent have been obtained using HTSEs.

In the present work, the authors study the electronic and magnetic properties of MnFe₂O₄. The results obtained by the experiment and by ab initio calculations were used in HTSE as input to deduce other physical parameters.

This paper aims to combine the results of magnetic measurements with high temperature series expansions to determine the magnetic phase diagram of SrMn_1−xFe_xO₃ 0≤x≤1 perovskites materials.

The authors have found antiferromagnetic ordering for lightly and heavily Fe‐substituted material, while intermediate substitution leads to spin‐glass behavior. Near the SrMn_0.5Fe_0.5O₃ composition these two types of ordering are found to coexist and affect one another.

The spin glass behavior may be caused by competing ferromagnetic and antiferromagnetic interactions among Mn⁴⁺ and observed Fe³⁺ and Fe⁵⁺ ions.

The magnetic perovskites materials are several application in industrial applications (spintronics, magnetic random‐access memory (MRAM), …).

The purpose of this paper is to study the magnetic properties and the hysteresis behavior of a ferrimagnetic cubic Ising nanowire with mixed spins S = 3/2 and S = 5/2 in which the atoms are placed alternately.

In order to investigate the effects of the exchange interactions and crystal field on the magnetic properties and hysteresis behavior of the nanowire, we have used the Monte Carlo simulation. More precisely, we have plotted the thermal variations of the sublattice and total magnetizations for different values of the Hamiltonian parameters, and we have presented the corresponding phase diagrams. In addition, the influence of an external magnetic field is examined by plotting the variations of hysteresis loops with the change of temperature and crystal field.

All phase transition found in this study are of second-order and the critical temperatures increase linearly with the increase of the exchange interactions. The compensation temperatures appear only for some domains of crystal field D and exchange interaction J_B of the sublattice (B). Moreover, when studying the hysteresis behavior, the system can show one or double hysteresis loops.

The authors consider that this research is consistent with the scientific axis of the journal which benefits a great esteem in our country and in the world. In addition, the results are of technological interest.

The purpose of this article is to investigate the magnetic properties and the hysteresis loops behavior of a ferrimagnetic cubic nanowire with mixed spins S_A = 3/2 and S_B = 2.

We have used the Monte Carlo simulation to examine the influences of the exchange interaction J_B, the crystal field ∆ and the temperature on the magnetic properties and hysteresis loops of the nanowire. More exactly, we have shown the temperature dependence of the sublattice magnetizations (m_A and m_B) and the total magnetization (M) for several values of the Hamiltonian parameters, as well as the corresponding phase diagrams. Finally, the effect of an external magnetic field is studied by plotting the hysteresis loops of the system for different values of exchange interaction, crystal field and temperature.

The obtained results show the existence of second-order phase transitions, as well as the compensation behavior. Moreover, according to the values of the Hamiltonian parameters, the system can exhibit one, two or three hysteresis loops.

The magnetic nanowires are of great interest in experimental works, but without theoretical explanations, the experimental results cannot be clarified in depth. For this, we contribute through this theoretical study to understand the nanowires, especially those with mixed spins (2, 3/2).

The purpose is to calculate the change in the total energy of a small fragment of an idealized lattice of iron (in its pure form and with impurity atoms) containing an edge dislocation during its elementary motion at one interatomic spacing, both under the influence of a constant magnetic field and without it. The introduction of a magnetic field into the system is aimed at checking the adequacy of the description of the phenomenon of magnetoplasticity by changing the total energy of the atomic system.

The design procedure is based on a quantum-mechanical description of the switching process of the covalent bond of atoms in the dislocation core. The authors used the method of density functional theory in the Kohn-Shem version, implemented in the GAUSSIAN 09 software package. Using the perturbation theory, the authors modeled the impact of an external constant magnetic field on the energy of a system of lattice atoms.

The simulation results confirmed the effect of an external constant magnetic field on the switching energy of the covalent bond of atoms in the dislocation core, and also a change in the magnetic susceptibility of a system of atoms with a dislocation. This complements the description of the magnetoplastic effect during the deformation of metals.

The authors created quantum-mechanical models of the dislocation motion in the Fe crystal lattice: without impurities, with a substitutional atom Cr and with an interstitial atom C. The models take into account the influence of an external constant magnetic field.

Prior research has examined the impact of corporate governance mechanisms, including external auditing, on accounting restatements likelihood. However, little is known about auditor’s monitoring role in restatement disclosure practices. The purpose of this study is to address this gap by investigating the impact of auditor’s oversight on the timeliness of accounting restatement disclosures as measured by the length of the restatement dark period.

The study examines panel data from a sample of restating publicly traded US firms. Negative binomial regression is used to analyze the data because the dependent variable is a count variable and is over-dispersed.

The main study’s results indicate that longer auditor tenure and non-audit services provision improve restatement disclosure timeliness. Conversely, companies whose auditors exerted abnormally high levels of audit effort have longer restatement dark periods.

This study is the first archival research that focuses on auditor’s monitoring role and its impact on the timeliness of restatement disclosures. By doing so, this study contributes to the auditing academic research, professional practice and regulation by providing empirical evidence on an exasperating issue for all participants in the financial markets. In addition, it provides a better understanding of auditor’s monitoring role in the accounting restatement process and offers insights to policymakers, practitioners and investors interested in corporate financial transparency and corporate governance.

This paper aims to review 68 archival studies on the impact of audit committees (ACs) on firms’ consequences [(non)financial reporting, performance and audit quality] in European firms.

Applying a stakeholder agency-theoretical framework, the author differentiates between three categories of AC variables: presence; composition; and resources, incentives and diligence.

The author finds that AC composition, (non)financial reporting and audit quality are dominant in the literature review. Other inputs or outputs are either too low in amount or yielded heterogeneous results, hindering clear tendencies. However, there are indications that financial expertise is positively related to financial reporting and audit quality, in line with agency theory and European regulatory assumptions.

In the discussion of potential future research, the author emphasizes, among others, the need for the recognition of innovative and sustainable AC variables, inclusion of moderator and especially mediator variables and reaction to endogeneity concerns by advanced regression models.

As the European Commission currently discusses extended regulations on AC duties and composition, this literature review highlights the huge impact of financial expertise on financial reporting and audit quality. In view of the increased monitoring duties of sustainability reporting, both business practices and regulatory bodies should increase the sustainability expertise of ACs.

This analysis makes useful contributions to prior research by focusing on attributes of AC and their impact on firms’ outputs in the European capital market, based on a differentiation between mandatory one-tier/two-tier systems and the choice model. The findings support the promotion of European evidence-based regulations, such as the Corporate Sustainability Reporting Directive and the Corporate Sustainability Due Diligence Directive.

The purpose of this paper is to present a new approach to measure the service quality provided by a public health-care service provider using the lean manufacturing concept. The research shows that the adoption of lean manufacturing principles and methodologies may be used as a measure for efficiency. The relative efficiency measure concept is introduced.

The inpatient and outpatient pharmacies providing medicines to the public at a large regional hospital in the southern part of the Kingdom of Saudi Arabia were the focus of this study. The lean manufacturing concept is used as a method to improve the service quality and reduce the time needed to deliver the medicine by comparing the efficiency between these two pharmacies based on a metric used in lean manufacturing called takt time. A team was formed to study the current situation, and recommendations based on lean manufacturing were suggested for implementations.

The research shows that the adoption of lean manufacturing principles and methodologies may be used as an efficiency measure to compare between different departments working under the same managerial system.

The results presented in this paper are reliable, objective and may be generalized for measuring the relative performance efficiency between several departments providing the same type of services.

The authors investigate the magnetic properties of a mixed spin-3/2 and spin-2 Blume-Capel model on square and cubic lattices with two different single-ion anisotropies.

To study the critical behavior of a mixed spin-3/2 and spin-2 system, the authors have used a real space renormalization group approximation and specifically the Migdal-Kadanoff technique. The authors give the phase diagrams for two different cases: (1) on the (Δ/|J|, 1/|J|) plane with Δ_A = Δ_B = Δ, and (2) on the (Δ_A/|J|, 1/|J|) and (Δ_B/|J|, 1/|J|) planes for selected values of Δ_B/|J| and Δ_A/|J|, respectively.

The phase diagrams obtained show that the system exhibits both second- and first-order phase transitions as well as tricritical points for some values of the anisotropies. Moreover, using the variation of the free energy and its derivative at low temperatures, the authors have seen the appearance of first-order transitions at very low temperatures.

Few investigations of mixed spin-3/2 and spin-2 systems with crystal field have been realized. For this reason, the authors use the renormalization group approach to complete the work done on these systems. In absence of an exact solution, this contributes to the synthesis of the approximation results on mixed spins models.

The purpose of this paper is to discuss the most relevant issues related to the impact of financial restatements in the dynamics of financial markets and identify several research gaps to be investigated in future research.

The methodology is based on a systematic review of the literature described by Tranfield et al. (2003). The final sample includes 47 academic papers published from 1996 to 2019.

Papers in this domain discuss three main topics: how the market prices the announcement of a financial restatement; how financial restatements affect the announcing firm’s cost of capital and how financial restatements affect firms’ reputation. There are several issues to explore in future research, including whether financial restatements affect the dynamics of financial markets in Europe, whether the market fully and promptly assimilates the information content of a restatement, the role of financial analysts’ information disclosures in this process or how regulators may improve the way they provide investors with timely information about firms’ restating problems.

There is always some degree of subjectivity in the definition of the keywords, search strings and selection criteria in a systematic review. These are all important aspects, as they delimitate the scope of the study and define the sample of papers to be reviewed.

The answers to the research questions identified in this paper may provide regulators with information to improve financial accounting and reporting standards and strengthen investors’ confidence in accounting information and the dynamics of financial markets.

This paper systematically reviews the relevant literature exploring the connection between financial restatements and the dynamics of financial markets. It contributes to the academic community by identifying several research questions that may impact the theory and practice related to accounting quality and capital markets.