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DC microgrids are revolutionizing energy systems by offering efficient, reliable, and sustainable solutions to modern power grid challenges. By directly integrating renewable energy sources and eliminating the inefficiencies of AC-DC conversion, these systems simplify energy distribution and enhance performance in critical applications such as data centers, electric vehicle charging, and telecommunications. This review paper comprehensively examines the design, implementation, and performance of DC microgrids in real-world settings. Key components, including distributed energy resources (DERs), energy storage systems (ESSs), and control strategies, are analyzed to highlight their roles in ensuring reliability and operational efficiency. This review also explores the challenges facing DC microgrids, such as stability issues, protection mechanisms, and high initial costs, while offering insights into advanced control strategies and modular designs to overcome these obstacles. Through an evaluation of global case studies, this article bridges the gap between theoretical research and practical deployment and also demonstrates how DC microgrids can enhance energy efficiency, support sustainable power generation, and provide resilience in various applications. The findings highlight the potential of DC microgrids as a cornerstone of future energy systems, enabling clean, reliable, and decentralized energy solutions.

Microgrids, with integrated PV systems and nonlinear loads, have grown significantly in popularity in recent years, making the evaluation of their transient behaviors in grid-connected and islanded operations paramount. This study examines a microgrid’s low-voltage ride-through (LVRT) and high-voltage ride-through (HVRT) capabilities in these operational scenarios. The microgrid’s behavior was analyzed using both electromagnetic transient (EMT) and RMS simulation methods. Two operational modes, grid-connected and islanded, were considered. A three-phase diesel generator acted as a reference machine in islanded mode. Findings highlighted distinct behaviors in the two operational modes. The EMT simulation revealed in-depth characteristics of electrical parameters, showing high-frequency oscillations more precisely than the RMS simulation. Additionally, the transient recovery times were longer in islanded mode compared to grid-connected mode. The EMT simulation offers a more detailed portrayal of transient behaviors than the RMS simulation, especially in capturing high-frequency disturbances. However, its completion time becomes significantly extended with longer simulation durations. Microgrids showcase distinct transient behaviors in grid-connected versus islanded modes, especially in LVRT and HVRT scenarios. These findings are critical for the design and operation of modern microgrids.

Introduction: Blood-brain barrier with strictly controlled activity participates in a coordinated transfer of bioactive molecules from the blood to the brain. Among different delivery approaches, gene delivery is touted as a promising strategy for the treatment of several nervous system disorders. The transfer of exogenous genetic elements is limited by the paucity of suitable carriers. As a correlate, designing high-efficiency biocarriers for gene delivery is challenging. This study aimed to deliver pEGFP-N1 plasmid into the brain parenchyma using CDX-modified chitosan (CS) nanoparticles (NPs). Methods: Herein, we attached CDX, a 16 amino acids peptide, to the CS polymer using bifunctional polyethylene glycol (PEG) formulated with sodium tripolyphosphate (TPP), by ionic gelation method. Developed NPs and their nanocomplexes with pEGFP-N1 (CS-PEG-CDX/pEGFP) were characterized using DLS, NMR, FTIR, and TEM analyses. For in vitro assays, a rat C6 glioma cell line was used for cell internalization efficiency. The biodistribution and brain localization of nanocomplexes were studied in a mouse model after intraperitoneal injection using in vivo imaging and fluorescent microscopy. Results: Our results showed that CS-PEG-CDX/pEGFP NPs were uptaken by glioma cells in a dose-dependent manner. In vivo imaging revealed successful entry into the brain parenchyma indicated with the expression of green fluorescent protein (GFP) as a reporter protein. However, the biodistribution of developed NPs was also evident in other organs especially the spleen, liver, heart, and kidneys. Conclusion: Based on our results, CS-PEG-CDX NPs can provide a safe and effective nanocarrier for brain gene delivery into the central nervous system (CNS).

Objective: Whistleblowing is one of the most important and effective fraud discovery mechanism; therefore, recognizing key factors affecting whistleblowing intention should be more considered by regulators; and they must try to encourage employees to whistle the blow. As whole, this research aim to modeling accountant whistleblowing intention.Methods: Moral intuition, theory of planed behavior and fraud triangle are three theoretical approaches that can be merged for modeling accountant intention to whistleblowing or not to whistle the blow. Thus, research model that designed on these approaches, is examined by several statistical tests include Delphi content analysis, Shannon entropy and structural equation model. Also, Swara technique is used for evaluating internal and external whistleblowing intention.Results: According to results, research model is approved and, also, interviewers intend to internal whistleblowing specially to chairman of board more than external whistleblowing.Conclusion: Accountants can play important role in reporting organizations fraud, so, managers should mange organization environment in a way that accountant intend to whistle the blow. Also, Legislators should make and sanction laws and regulations that support whistleblower hip-and-thigh

Iranian culture and civilization, despite the ethnic and racial diversity of the inhabitants of this land, the political developments and the invasion of the invaders and settlers, have always been regarded as an appropriate context for the advancement of Iranian art. Iranians have been involved in decorative arts as well as painting since ancient times, one of which being exquisite tile art. Decorating tiles in Islamic buildings as valuable treasures reflects the cultural ideas and religious beliefs of the artists of all times, and their taste and ability in this art have endured. Tile art, which gradually progressed from pre-Islamic centuries, reaches its peak of development and perfection in the Seljuk and Timurid times. Tile, which is the most beautiful and unique decorative element of architecture in the interior and exterior of buildings, not only creates the most spectacular color scenes and motifs in Iranian buildings, especially in religious sites, but it also is a factor in the strength and cover for the building. The finest examples of tile history of Iran, the inner and outer surfaces of the sacred doorstep of Imam Ali ibn Musa al-Reza (AS), are in front of our eyes through the many ups and downs of this land, making this valuable art endure, rather than be dissolved and forgotten. Geometric motifs have been used in pre-historic times in Iranian artworks, examples of which include pottery left from the civilizations of the hills of Sialk, Shush, Tal Bacon, and more. In the Islamic era, geometric motifs, especially knots, have been used in a variety of visual and decorative arts such as architecture and tiling of religious and non-religious buildings. The numerous and varied geometrical motifs (knots) seen in Iranian tile art and influencing the architectural ornamentation of other Islamic countries have generally been derived from a combination of a number of basic shapes, and by observing the constant rules of repetitive drawing have also been expanding throughout eras. These motifs, in addition to providing the viewer with visual pleasure, imply higher meanings within themselves that must be interpreted in order to be understood. From the Islamic point of view, these motifs and the way of their creation are symbolic ways of expressing the monotheism, which is the supernatural doctrine of divine unity as the origin and resurrection of all creatures. Through his sacred artistic spirit, the Muslim artist has achieved a two-dimensional reality in his artistic creations by departing from the three-dimensional elements of the creation world. In a concise way, this artist portrayed Islamic geometric art based on qualitative roles, based on mathematics and geometry, bringing together geometric shapes to achieve an element such as knot, which is in fact a mysterious knot of existence and polished the soul to prepare it to receive the truth. The holy shrine of Imam Ali-ibn-Musa al-Reza (AS) is a magnificent collection of the best tile art examples from different periods, which reached its peak of progress and perfection in the Seljuk and Timurid periods. Moreover, the geometric patterns of these tiles, with spiritually elevated meanings, embody a return to the world of monotheism by displaying unity in plurality and plurality in unity. This is why the best examples of tile art have appeared in these two periods. The present research aims to answer the following questions: Which geometric patterns have been used more often in the tiles of Imam Reza (AS)’s Shrine during the Seljuk and Timurid periods? What changes have occurred in the structures, colors, compositions and foundations of the patterns? And what similarities and differences exist among the geometric patterns of the tiles? This study has used a descriptive-comparative method and a historical analysis to show the developments in the Shrine’s tiles. The required data have been collected using a combination of library oriented and observational methods as well as tools such as books, articles, notes, tables, computer, and by referring to the tiles of the Imam Reza (AS)’s Shrine as well as their images. The geometric patterns were analyzed based on their foundations, compositions and colors, and the findings indicated similarities between the two periods in terms of the foundations and structures of the patterns and showed that most of the patterns are based on the geometric shape of the eight-pointed star. The tiles are quite similar in color, especially in the primary colors, but the compositions of the patterns (strap work) have no similarity, although all of them have the same shape. Although there were many tile samples from the Timurid period, only one from the Seljuk period, the geometric shape of the eight-pointed star, can be considered a meaningful common code in both periods.

In remote areas, extending a power line to the primary electricity grid can be very expensive and power losses are high, making connections to the grid almost impossible. A well-designed microgrid that integrates renewable energy resources can help remote areas reduce investment costs and power losses while providing a reliable power source. Therefore, investigating the design of an independent and economically practical microgrid system for these areas is necessary and plays an important role. This paper introduces a design procedure to design an isolated microgrid using HOMER software (HOMERPro 3.14.5) for remote areas. In Vietnam, due to the obstruction of the mountainous terrain or the isolated island location, many remote areas or islands need electrification. A simple case study of a hybrid system with a 60 kW peak load demand on Con Dao island in Vietnam is used to illustrate the proposed design method. Specifically, a hybrid system that includes a PV system, batteries, and a diesel generator is designed. To provide the full information of the designed hybrid system designed, each solution is analyzed and evaluated in detail according to the sensitivity parameters.

This applied descriptive mixed-methods research set out to propose a productivity-oriented model to enhance professional credentials of faculty members at Tehran Science and Research Branch of Islamic Azad University. The research population comprised all faculty members of the Science and Research Branch of the Azad University. Initially, the indicators of faculty members’ professional efficacy enhancement model were qualitatively specified via the Delphi technique. Having verified the content validity of the proposed questionnaire, it was subsequently piloted by distributing it among a larger sample and its reliability was confirmed through z test and Cronbach's alpha, respectively. The collected research data were analyzed using t and z tests, Structural Equational Modelling (SEM), Friedman, Kolmogorov-Smirnov, Bartlett, KMO and factor analysis. The findings revealed that the participants had identified 6 types of educational, technological, research and specialized services credentials like individual and value, organizational and perceptual competencies, all of which were confirmed in the final model. Moreover, the findings underscored the unsatisfactory level of these credentials in both the existing and desirable situations and the need to improve them.

Smart textiles are currently being pursued for actuation and sensing for their potential to directly incorporate "intelligence" into the fabric, in contrast to wearable technologies. In smart textiles, smart materials (e.g., piezoelectric) are formed into yarns that are woven into fabrics for clothing. One immediate requirement for such textiles is their stability during washing cycles, as expected of any clothing items, which has been largely lacking so far. Here, we investigate the washing stability of nanofibrous piezoelectric textiles. Our results reveal that electrospun textiles exhibit remarkable structural stability from the fiber microstructure to the textile level. Overall fiber crystalline composition and electroactive β phase remain stable within 1% of ~47% and ~85%, respectively. Mechanically, the textile displays sustained performance, with only negligible changes observed. The yield strain and stress only show a ~8% and 9% differences, respectively. Moreover, piezoelectric stability is confirmed through β phase preservation and slight variation in voltage output of ~6%. These results prove the candidacy that the processing of electrospun polyvinylidene fluoride (PVDF) fibers to woven textiles is applicable to the demands of smart textiles, which is expected to accelerate the commercialization of such textiles for wearable robotics and health monitoring. [ABSTRACT FROM AUTHOR]

Advances in vat photopolymerization 3D printing have the potential to significantly improve the production of ceramic materials for electrochemical energy devices. Solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs) necessitate high‐resolution ceramic manufacturing methods, as well as precisely controlled porosity (≈20–40%) for optimal gas transport. Achieving a balance between this porosity and mechanical integrity, especially under thermal stress, remains a challenge. Herein, the successful fabrication of porous yttria‐stabilized zirconia (YSZ) ceramics using vat photopolymerization 3D printing is demonstrated, achieving porosities ranging from 6% to 40% and corresponding grain sizes of ≈80–550 nm. It is found that 3D‐printed YSZ with ≈33% porosity exhibited a Weibull modulus of m = 5.3 and a characteristic strength of over 36 MPa. In the investigation, it is further revealed that these ceramics can withstand thermal shock up to 500 °C, retaining over 70% of their flexural strength. This remarkable performance suggests significant potential for 3D‐printed porous YSZ in SOFCs and SOECs, paving the way for potential improved efficiency, reduced fabrication costs, and innovative designs in these next‐generation clean energy technologies. [ABSTRACT FROM AUTHOR]

Abstract Background Thyroid dysfunction during pregnancy is associated with adverse outcomes for both mother and fetus. The present meta-analysis was conducted to evaluate thyroid dysfunction in Iranian pregnant women. Methods We registered this review at PROSPERO (registration number: CRD42020166655). The research steps in this systematic review and meta-analysis were performed according to the MOOSE protocol, and finally, reports were provided based on the PRISMA guidelines. The literature search was performed in October 2019 using the international online databases, including Web of Science, Ovid, Science Direct, Scopus, EMBASE, PubMed/Medline, Cochrane Library, EBSCO, CINAHL, Google Scholar as well as national databases were reviewed. Data were extracted after applying the inclusion and exclusion criteria and qualitative evaluation of the studies. I2 index and Q test were used to assess differences in studies. All analyses were performed using Comprehensive Meta-Analysis Software. P-value less than 0.05 was considered statistically significant. We identified 1261 potential articles from the databases, and 426 articles remained after removing the duplicate and unrelated studies. After evaluating the full text, 52 articles were removed. Results Finally, 19 eligible studies including 17,670 pregnant women included for meta-analysis. The prevalence of thyroid dysfunction in Iranian pregnant women was 18.10% (95%CI: 13.89–23.25). The prevalence of hypothyroidism, clinical hypothyroidism, and subclinical hypothyroidism in Iranian pregnant women was respectively estimated to be 13.01% (95%CI: 9.15–18.17), 1.35% (95%CI: 0.97–1.86) and 11.90% (95%CI: 7.40–18.57). The prevalence of hyperthyroidism, clinical hyperthyroidism, and subclinical hyperthyroidism in Iranian pregnant women was respectively estimated to be 3.31% (95%CI: 1.62–6.61), 1.06% (95%CI: 0.61–1.84) and 2.56% (95%CI: 0.90–7.05). The prevalence of anti-thyroperoxidase antibody was estimated to be 11.68% (95%CI: 7.92–16.89). Conclusion The results of this meta-analysis showed a high prevalence of thyroid disorders, especially hypothyroidism. The decision to recommend thyroid screening during pregnancy for all women is still under debate, because the positive effects of treatment on pregnancy outcomes must be ensured. On the other hand, evidence about the effect of thyroid screening and treatment of thyroid disorders on pregnancy outcomes is still insufficient. Nevertheless, a large percentage of general practitioners, obstetricians and gynecologists perform screening procedures in Iran.

The journey towards transportation electrification started with electric vehicles and has attracted more and more attention on a global scale in recent years. EVs are seen as a substantial, effective, and urgent solution for transportation electrification. In this paper, we investigate the operation requirements for integrating charger stations into the distribution grid in Vietnam. We also propose a simple evaluation method for assessing the feasibility of integrating planned unidirectional EV chargers into the distribution grid. The assessment method is applied to two main distribution feeders in Danang, Vietnam, where the new charger stations are already planned to be deployed in 2025 and 2030. The results showed that with addition of pre-planned EV chargers, both feeders still meet operation requirements in 2025 and 2030. However, the feeder with voltage indices close to the limit needs to be considered for an upgrade in configuration.

Research findings have revealed that entrepreneurial trends in Iranian state organizations have not succeeded and to rectify the situation entails reforming enhancing human resource management policies. Thus, based on Mirsepasi’s Model which is one of the underlying principles of human resource management system, the present study intended to offer an appropriate model for absorbing, supplying and adjusting human resources that can promote entrepreneurship in Iranian state organizations. To this end, the service compensation system, job design and employment management were selected from Mirsepasi’s Model and considered via confirmatory factor analysis. Based on expert judgement and Scott’s reliability coefficient, innovation, proactivity and flexibility were also selected as dimensions of corporate entrepreneurship in Iranian public sectors. The research population consisted of 18 active ministries of the Islamic Republic of Iran that were stratified into five categories of educational, economic, political-authoritative, cultural, welfare and general service ministries. Unit of analysis in this study was managers and experts in human resource management departments who were selected using convenience sampling from a single randomly selected ministry from each category. Further, the entrepreneurial hindrances were considered in human resource absorption, supply and adjustment employing LISREL software. The Model presented here is claimed to support innovation, proactivity and flexibility as identified aspects of entrepreneurship in state organizations via service compensation system employment recruitment and job design.

Today, the use of nutrients derived from natural bioactive compounds application in the food, pharmaceutical, and cosmetic industries is on the increase. This paper aimed to evaluate the amino acids profile (essential and non-essential) and pigments composition (chlorophyll a, carotenoids, and phycocyanin) of Arthrospira platensis (a blue-green microalga) cultivation in a flat-plate photobioreactor under various types of light-emitting diodes (red: 620–680 nm, white: 380–780 nm, yellow: 570–600nm, blue: 445–480 nm). The maximum biomass concentration (604.96 mg L−1) occurred when the red LED was applied for cultivation, and the minimum biomass concentration (279.39 mg L−1) was obtained under blue LED. The sequence of pigments and amino acids concentrations (mg L−1culture volume) was approximately in accordance with the biomass productivity. It means the red light produces the maximum concentration of pigments (chlorophyll a: 5.42, carotenoids: 2.92, phycocyanin: 67.54 mg L−1) and amino acids (essential amino acids: 110.47, nonessential amino acids: 179.10 mg L−1). Nevertheless, when these values were measured in mg per g of dry weight, the utmost contents were observed in microalgal products cultivated under blue LED. These consequences are due to the highest cell productivity and the most extended length of cells that occurred under red and blue LEDs, respectively. Highlights: Spectral light quality is an effective parameter on Spirulina platensis growth. Red light produces the highest biomass productivity. Pigment and amino acids concentrations have conformity with biomass productivity. Blue light causes the cells to be longer. Longer cells have more time to synthesize the intracellular compounds. [ABSTRACT FROM AUTHOR]

Objective: Considering complex financial plans to conceal fraud in financial statements, the development of fraud detection methods can be regarded as solution for this problem. The present study uses the bee algorithm to develop methods for fraud detection in financial statements. Method: Three methods of bee algorithm, genetic algorithm and logistic regression have been used to study the subject. The statistical sample consists of 120 companies accepted in the Tehran Stock Exchange (60 companies are suspected of fraud and 60 ones are not suspected) for the period 1396-1385. The companies were suspected of fraud, based on 1) revised audit opinion after unacceptable expression, 2) existence of significant annual revisions, and revised financial statements for inventories and other assets; 3) existence of tax disputes with the tax area, according to notes on income tax filing, general tax filings and conditioned clauses in audit reports. Following the use of cross-entropy, 16 financial ratios were introduced as the potential predictors of fraudulent financial reporting. Result: The results showed that the bee algorithm method with prediction accuracy of 82.5% has better performance in identifying suspicious companies in fraudulent financial statements than the other two methods. Conclusion: The results of the research indicate that the proposed method of this study compared to other methods has higher rate of prediction accuracy, lower error rate and relatively good speed.

Maziar Bahreini,1 Monireh Movahedi,2 Maryam Peyvandi,3 Fereshteh Nematollahi,4 Hessam Sepasi Tehrani21Department of Chemistry, North Tehran Branch, Islamic Azad University, Tehran, Iran; 2Department of Cellular and Molecular, Faculty of Biological Sciences, North Tehran Branch, Islamic Azad University, Tehran, Iran; 3Department of Biology, Faculty of Biological Sciences, North Tehran Branch, Islamic Azad University, Tehran, Iran; 4Department of Chemistry, East Tehran Branch, Islamic Azad University, Tehran, IranPurpose: Evaluation of structural features, thermodynamics and kinetic properties of carbon nanofibers (CNFs) as artificial nanoscale enzymes (nanozyme).Methods: Synthesis of CNFs was done using chemical vapor deposition, and transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and energy-dispersive x-ray spectroscopy (EDX) were used to provide information on the morphology, elemental monitoring and impurity assay of the CNFs. The thermal features of the CNFs were evaluated using differential thermal analysis (DTA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) derivative and TGA. The calculated thermo-physical parameters were melting temperature (Tm), weight loss maximum temperature (Tmax) and enthalpy of fusion (ΔHfusion). Catalytic activity was assayed by a 4-aminoantypyrine (4-AAP)-H2O2 coupled colorimetric system by UV-visible spectroscopy.Results: FE-SEM and TEM analysis demonstrated parallel graphitic layers and uniformity of atomic orientation and morphology. The EDX spectra approved carbon element as major signal and presence of partial Ti as impurities of CNFs during CVD process. The DTA thermogram showed the endothermic process had a maximum temperature of 82.27°C at −15.48 mV and that thermal decomposition occurred at about 200°C. The TGA-differential gravimetric analysis thermogram showed that Tmax was 700°C. The DSC heat flow curve showed a melting temperature (Tm) of 254.52°C, ΔHfusion of 3.84 J^.g−1, area under the curve of 58.58 mJ and Te (onset) and Tf (end set) temperatures of 246.60°C and 285.67°C, respectively. The peroxidase activity of the CNFs obeyed the Michaelis–Menten equation with a double-reciprocal curve and the calculated Km, Kcat and Vmax kinetic parameters.Conclusion: CNFs as peroxidase nanozymes are intrinsically strong and stable nanocatalysts under difficult thermal conditions. The peroxidase activity was demonstrated, making these CNFs candidates for analytical tools under extreme conditions.Keywords: nanozyme, carbon nanofibers, 4-AAP

Radiated waves from mobile phones are in the Radio Frequency (RF) range, so those are unable to cause ionization and electron excitation. RF that are produced and emitted from sender antenna on the surface of mobile phone systems, ranges from 30 up to 300 GHz in electromagnetic wave spectrum. There is no complete information about the effects of RF on protein changes. For this purpose, we have examined the effects of RF waves on the changes in protein expression pattern of the brain. In this study, 10 heads of male Wistar rats, weighing between 200-250 g, were exposed to transmission antenna in 100-180 meter distance. Then, proteome of RF900 GHz exposed group and control group were extracted. Two-dimensional gel electrophoresis evaluation and proteomics analysis was performed. Results showed altered proteome pattern due to radiation. Tissue exposed to nonstandard waves showed similar pattern of changes in the expression of some proteins, which have key roles in the induction of apoptosis. The expressions of key proteins including Bcl-2-A1, Bid, Neurofilament and Cytochrome Oxidase were decreased. Expression or suppression of apoptosis related proteins such as BCL-2 in rat brain proteome exposed to standard RF900 MHz (at 180m and beyond), can serve as a biomarker of brain activity, memory and sleep. RF radiated from transmission antenna in urban and standard spaces may not be carcinogenic, but, individuals exposed in nonstandard distances to those antennas (less than 180meter) may be at risk. HIGHLIGHTS •Radio Frequency (RF) waves can affect the protein expression profile of the cell. •Exposure to nonstandard RF waves changed the expression profile of apoptosis key proteins. •Changes in the expression of Bcl-2-A1, Bid, Neurofilament and Cytochrome Oxidase under the RF was evident.

Background: Chronic lymphocytic leukemia (CLL), a common neoplastic disease, is associated with the accumulation of B-lymphocytes in the hematopoietic organs. A main characteristic of CLL cells is the failure to undergo apoptosis, thus resulting in resistance to several chemotherapeutics. Doxorubicin (DOX), an anthracycline widely used for treating various neoplasms including CLL, induces apoptosis via several mechanisms. Despite this, CLL cells become resistant to DOX. A major protein known as B-cell lymphoma-2 (Bcl-2), known to exert direct anti-apoptotic effects on the cell, is reported to be overexpressed in CLL cells. Methods: We aimed to silence the Bcl-2 gene by siRNA. Mononuclear cells were isolated from the peripheral blood and bone marrow of eleven untreated CLL patients by Ficoll-Paque. To transfect cells, we used Lipofectamine. Bcl-2 expression was investigated using qRT-PCR. Next, we studied the effect of Bcl-2 silencing in combination with DOX treatment on the viability of cells by an MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. Results: Bcl-2 expression was significantly suppressed in CLL cells following siRNA transfection via lipofectamine. Based on the results of MTT, the inhibition of Bcl-2 sensitized CLL cells to DOX treatment. Also, the effect of the treatment was time-dependent. Conclusion: These findings imply that combination therapy of CLL using anti-Bcl-2 siRNA and DOX can be considered a practical therapeutic approach that should be further evaluated in future studies.