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1.
Angew Chem Int Ed Engl ; : e202411255, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980971

RESUMEN

Conversion-type electrode materials have gained massive research attention in sodium-ion batteries (SIBs), but their limited reversibility hampers practical use. Herein, we report a bifunctional nanoreactor to boost highly reversible sodium-ion storage, wherein a record-high reversible degree of 85.65% is achieved for MoS2 anodes. Composed of nitrogen-doped carbon-supported single atom Mn (NC-SAMn), this bifunctional nanoreactor concurrently confines active materials spatially and catalyzes reaction kinetics. In-situ/ex-situ characterizations including spectroscopy, microscopy, and electrochemistry, combined with theoretical simulations containing density functional theory and molecular dynamics, confirm that the NC-SAMn nanoreactors facilitate the electron/ion transfer, promote the distribution and interconnection of discharging products (Na2S/Mo), and reduce the Na2S decomposition barrier.As a result, the nanoreactor-promoted MoS2 anodes exhibit ultra-stable cycling with a capacity retention of 99.86% after 200 cycles in the full cell. This work demonstrates the superiority of bifunctional nanoreactors with two-dimensional confined and catalytic effects, providing a feasible approach to improve the reversibility for a wide range of conversion-type electrode materials, thereby enhancing the application potential for long-cycled SIBs.

2.
J Can Acad Child Adolesc Psychiatry ; 33(2): 145-153, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38952790

RESUMEN

Over the last ten years, there has been a substantial increase in the number of children and adolescents referred to gender clinics for possible gender dysphoria. The gender affirming model of care, a dominant treatment approach in Canada, is based on low quality evidence. Other countries are realizing this and making psychosocial treatments and/or exploratory psychotherapy a first line of treatment for gender related distress in young patients. Psychodynamic (exploratory) psychotherapy has established efficacy for a range of conditions, and has been used in youth and adults with gender dysphoria. In Canada, the adoption of psychodynamic psychotherapy for gender dysphoria is impeded by some academics who argue that it may violate laws against conversion therapy. Psychodynamic psychotherapy is not conversion therapy and should be made available in Canada as a treatment modality for gender dysphoria.

3.
Chempluschem ; : e202400069, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38955991

RESUMEN

Covalent organic frameworks (COFs) are an innovative class of crystalline porous polymers composed of light elements such as C, N, O, etc., linked by covalent bonds. The distinctive properties of COFs, including designable building blocks, large specific surface area, tunable pore size, abundant active sites, and remarkable stability, have led their widespread applications in electrocatalysis. In recent years, COF-based electrocatalysts have made remarkable progress in various electrocatalytic fields, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, nitrogen reduction reaction, nitrate reduction reaction, and carbon dioxide reduction reaction. This review begins with an introduction to the design and synthesis strategies employed for COF-based electrocatalysts. These strategies include heteroatom doping, metalation of COF and building monomers, encapsulation of active sites within COF pores, and the development of COF-based derived materials. Subsequently, a systematic overview of the recent advancements in the application of COF-based catalysts in electrocatalysis is presented. Finally, the review discusses the main challenges and outlines possible avenues for the future development of COF-based electrocatalysts.

4.
Chemphyschem ; : e202400505, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38978281

RESUMEN

In the catalytic transformation of bio-oil into liquid fuels having alkanes via hydrodeoxygenation (HDO), the acid and metal sites in the catalyst are pivotal for promoting the HDO of lignin-derived phenolic compounds. This study introduces a novel bifunctional catalyst comprising phosphomolybdenum-vanadium heteropolyacids (H4PMo11VO40) coupled with Ni/C. The HDO reaction of the model compound guaiacol was carried out under reaction conditions of 230 °C, revealing the superior performance of H4PMo11VO40 with Ni/C catalysts compared to the conventional acids, even at low dosage. The Keggin structure of H4PMo11VO40 provided a solid catalyst with strong acidic and redox properties, alongside advantages such as ease of synthesis, cost-effectiveness, and tunable acid and redox properties at the molecular level. Characterization of Ni/C and the prepared acid demonstrated favorable pore structure with a mesopore volume of 0.281 cm3/g and an average pore size of 3.404 nm, facilitating uniform distribution and catalytic activity of Ni-metal. Incorporating acid enhances the acidic sites, fostering synergistic interactions between metal and acidic sites within the catalyst, thereby significantly enhancing HDO performance. Guaiacol conversion at 230 °C reached 100%, with a cyclohexane selectivity of 89.3%. This study presents a promising pathway for converting lignin-derived phenolic compounds.

5.
PeerJ Comput Sci ; 10: e2144, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38983216

RESUMEN

Lead generation is the process of gaining potential customers' interest to increase future sales, and it is an essential part of many businesses' (amusement parks, theme parks, clubs, etc.) sales processes as their membership is more expensive. The main objective of these businesses is to increase the count of customers. By generating sales leads, a club/park can find leads who have already expressed interest in its products and services and access their audience potential, allowing them to focus on future marketing and sales efforts on those leads that are more likely to convert. The current work focuses on how to convert a lead to a customer in optimum number of days. We collect two kinds of data: customer data and lead generation data. The customer data consists of all the leads who have taken the membership, and the lead generation data consists of all current leads. The details of those converted from a lead into a customer in the last 60 days are filtered out from the customer data. Using this data, patterns are generated, which are used to predict the following activity (step) for qualified leads, along with the optimal number of days required to complete that activity. This optimal number of days is found using the Hybrid Chaotic Pattern Search Algorithm (HCPSA). This novel approach here helps in boosting sales by prioritizing leads who have expressed interest and identifying the optimal window for converting them into paying customers. This strategy holds significant potential to benefit businesses across various industries.

6.
Cell Rep ; 43(7): 114482, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38985670

RESUMEN

Secretory granule (SG) fusion is an intermediate step in SG biogenesis. However, the precise mechanism of this process is not completely understood. We show that Golgi-derived mast cell (MC) SGs enlarge through a mechanism that is dependent on phosphoinositide (PI) remodeling and fusion with LC3+ late endosomes (amphisomes), which serve as hubs for the fusion of multiple individual SGs. Amphisome formation is regulated by the tyrosine phosphatase PTPN9, while the subsequent SG fusion event is additionally regulated by the tetraspanin protein CD63 and by PI4K. We also demonstrate that fusion with amphisomes imparts to SGs their capacity of regulated release of exosomes. Finally, we show that conversion of PI(3,4,5)P3 to PI(4,5)P2 and the subsequent recruitment of dynamin stimulate SG fission. Our data unveil a key role for lipid-regulated interactions with the endocytic and autophagic systems in controlling the size and number of SGs and their capacity to release exosomes.

7.
Ultrasonics ; 142: 107399, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38986246

RESUMEN

Guided ultrasonic waves can be employed for efficient structural health monitoring (SHM) and non-destructive evaluation (NDE), as they can propagate long distances along thin structures. The scattering (S0 mode) and mode conversion of low frequency guided waves (S0 to A0 and SH0 wave modes) at part-thickness crack-like defects was studied to quantify the defect detection sensitivity. Three-dimensional (3D) Finite Element (FE) modelling was used to predict the mode conversion and scattering of the fundamental guided wave modes. Experimentally, the S0 mode was excited by a piezoelectric (PZT) transducer in an aluminum plate. A laser vibrometer was used to measure the out-of-plane displacement to characterize the mode-converted A0 mode, employing baseline subtraction to achieve mode and pulse separation. Good agreement between FE model predictions and experimental results was obtained for perpendicular incidence of the S0 mode. The influence of defect depth and length on the scattering and mode conversion was studied and the sensitivity for part-thickness defects was quantified. The maximum mode conversion (S0-A0 mode) occurred for ¾ defect depth and the amplitude of the mode-converted A0 and scattered S0 modes mostly increased linearly as the defect length increased with an almost constant A0/S0 mode scattered amplitude ratio. Similar forward and backward scattering amplitude was found for the mode converted A0 mode. The mode conversion of the S0 to SH0 mode has the highest sensitivity for short defects, but the SH0 mode amplitude only increased slightly for longer defects. Employing the information contained in the mode-converted, scattered guided ultrasonic wave modes could improve the detection sensitivity and localization accuracy of SHM algorithms.

8.
Environ Pollut ; : 124516, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38986764

RESUMEN

The escalating volume of sewage sludge (SS) generated poses challenges in disposal, given its potential harm to the environment and human health. This study explored sustainable solutions for SS management with a focus on energy recovery. Employing CO2-assisted pyrolysis, we converted SS into flammable gases (H2 and CO; syngas). Single-stage pyrolysis of SS in a CO2 conditions demonstrated that CO2 enhances flammable gas production (especially CO) through gas phase reactions (GPRs) with volatile matter (VM) at temperatures ≥ 520 ˚C. Specifically, the CO2 partially oxidized the VM released from SS and concurrently underwent reduction into CO. To enhance the syngas production at temperatures ≤ 520 ˚C, multi-stage pyrolysis setup with additional heat energy and a Ni/Al2O3 catalyst were utilized. These configurations significantly increased flammable gas production, particularly CO, at temperatures ≤ 520 ˚C. Indeed, the flammable gas yield in the catalytic pyrolysis of SS increased from 200.3 mmol under N2 conditions to 219.2 mmol under CO2 conditions, representing a 4.4-fold increase compared to single-stage pyrolysis under CO2 conditions (50.0 mmol). By integrating a water-gas-shift reaction, the flammable gases produced from CO2-assisted catalytic pyrolysis were expected to have the potential to generate revenue of US$4.04 billion. These findings highlight the effectiveness of employing CO2 in SS pyrolysis as a sustainable and effective approach for treating and valorising SS into valuable energy resources.

9.
Cancer Cell Int ; 24(1): 240, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982390

RESUMEN

DNA methylation is an important molecular modification that plays a key role in the expression of cancer genes. Evaluation of epigenetic changes, hypomethylation and hypermethylation, in specific genes are applied for cancer diagnosis. Numerous studies have concentrated on describing DNA methylation patterns as biomarkers for cancer diagnosis monitoring and predicting response to cancer therapy. Various techniques for detecting DNA methylation status in cancers are based on sodium bisulfite treatment. According to the application of these methods in research and clinical studies, they have a number of advantages and disadvantages. The current review highlights sodium bisulfite treatment-based techniques, as well as, the advantages, drawbacks, and applications of these methods in the evaluation of human cancers.

10.
ChemSusChem ; : e202401082, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39021290

RESUMEN

The direct conversion of CO2 in flue gas to value-added chemicals is a potentially important cost-effective solar-driven CO2 reduction technology. The present work demonstrates the solar-powered conversion of CO2 to CO with greater than 10% efficiency using a Mn complex cathode and an Fe-Ni anode in a single-compartment reactor without an ion exchange membrane in conjunction with a Si solar cell. Reactors separated by ion exchange membranes are typically used to prevent any effects of oxygen generated by the counter electrode. However, the present Mn complex catalyst maintained its activity even in the presence of 15% O2. Operando surface-enhanced Raman spectroscopy established that the present Mn catalyst preferentially reacted with CO2 without adsorbing O2. This unique characteristic enabled solar-driven CO2 reduction using a single-compartment reactor. In contrast, catalytic metals such as Ag tend to lose activity in such systems as a consequence of reaction with oxygen produced at the anode.

11.
Small ; : e2404012, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39022999

RESUMEN

Despite recent revolutionary advancements in photovoltaic (PV) technology, further improving cell efficiencies toward their Shockley-Queisser (SQ) limits remains challenging due to inherent optical, electrical, and thermal losses. Currently, most research focuses on improving optical and electrical performance through maximizing spectral utilization and suppressing carrier recombination losses, while there is a serious lack of effective opto-electro-thermal coupled management, which, however, is crucial for further improving PV performance and the practical application of PV devices. In this article, the energy conversion and loss processes of a PV device (with a specific focus on perovskite solar cells) are detailed under both steady-state and transient processes through rigorous opto-electro-thermal coupling simulation. By innovatively coupling multi-physical behaviors of photon management, carrier/ion transport, and thermodynamics, it meticulously quantifies and analyzes energy losses across optical, electrical, and thermal domains, identifies heat components amenable to regulation, and proposes specific regulatory means, evaluates their impact on device efficiency and operating temperature, offering valuable insights to advance PV technology for practical applications.

12.
Luminescence ; 39(7): e4836, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39023133

RESUMEN

The near-infrared (NIR) down-conversion process for broadband sensitization has been studied in Eu2+-Nd3+ co-doped BaAl2O4. This material has a broad absorption band of 200-480 nm and can convert photons in the visible region into NIR photons. The NIR emission at 1064 nm, attributed to the Nd3+:4F3/2 → 4I11/2 transition, matches the bandgap of Si, allowing Si solar cells to utilize the solar spectrum better. The energy transfer (ET) process between Eu2+ and Nd3+ was demonstrated using photoluminescence spectra and luminescence decay curves, and Eu2+ may transfer energy to Nd3+ through the cooperative energy transfer (CET) to achieve the down-conversion process. The energy transfer efficiency (ETE) and theoretical quantum efficiency (QE) were 68.61% and 156.34%, respectively, when 4 mol% Nd3+ was introduced. The results indicate that BaAl2O4:Eu2+-Nd3+ can serve as a potential modulator of the solar spectrum and is expected to be applied to Si solar cells.


Asunto(s)
Europio , Rayos Infrarrojos , Neodimio , Silicio , Energía Solar , Europio/química , Silicio/química , Neodimio/química , Luminiscencia , Transferencia de Energía , Bario/química , Mediciones Luminiscentes
13.
World J Orthop ; 15(6): 554-559, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38947266

RESUMEN

BACKGROUND: Hip resurfacing arthroplasty (HRA) is an alternative to total hip arthroplasty (THA) that is typically reserved for young active patients because it preserves bone. However, the benefits of HRA only hold true if conversion THA after failed HRA provides acceptable outcomes. AIM: To compare patient reported outcomes for conversion THA after HRA failure to primary THA. METHODS: A retrospective review of 36 patients (37 hips) that underwent conversion THA for failed HRA between October 2006 and May 2019 by a single surgeon was performed. Patient reported outcomes [modified Harris Hip Score (mHHS), University of California Los Angeles (UCLA) activity score] were obtained via an email-based responder-anonymous survey. Outcomes were compared to normative data of a primary THA cohort with similar demographics. Subgroup analysis was performed comparing outcomes of conversion THA for adverse local tissue reaction (ALTR) vs all other causes for failure. RESULTS: The study group had a lower mHHS than the control group (81.7 ± 13.8 vs 90.2 ± 11.6, P < 0.01); however, both groups had similar UCLA activity levels (7.5 ± 2.3 vs 7.2 ± 1.6, P = 0.51). Patients that underwent conversion for non-ATLR causes had similar mHHS (85.2 ± 11.5 vs 90.2 ± 11.6, P = 0.11) and higher UCLA activity levels (8.5 ± 1.8 vs 7.2 ± 1.6, P < 0.01) compared to the control group. Patients that underwent conversion for ATLR had worse mHHS (77.1 ± 14.5 vs 90.2 ± 11.6, P < 0.01) and UCLA activity levels (6.1 ± 2.3 vs 7.2 ± 1.6, P = 0.05) when compared to the control group. CONCLUSION: Patient outcomes equivalent to primary THA can be achieved following HRA conversion to THA. However, inferior outcomes were demonstrated for ALTR-related HRA failure. Patient selection and perhaps further studies examining alternative HRA bearing surfaces should be considered.

14.
Glob Health Med ; 6(3): 170-173, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38947413

RESUMEN

The recent dramatic progress in systemic therapy for hepatocellular carcinoma (HCC) provides the possibility of a combination of surgery and systemic therapy including adjuvant, neoadjuvant, or conversion settings. Since the turn of the century, at least three negative studies have tested adjuvant therapies after curative resection or ablation, including uracil-tegafur, which is an oral chemotherapeutic drug, sorafenib, and peretinoin, which a synthetic retinoid that may induce the apoptosis and differentiation of liver cancer cells. Using more potent immuno-checkpoint inhibitors (ICIs), at least 4 phase III trials of adjuvant immunotherapy are ongoing: nivolumab, durvalumab/ bevacizumab, pembrolizumab, and atezolizumab+bevacizumab. Very recently, the last trial indicated a significantly better recurrence-free survival (RFS) for adjuvant atezolizumab+bevacizumab. Another promising combination of surgery and systemic therapy is neoadjuvant therapy for potentially resectable cases or a conversion strategy for oncologically unresectable cases. There are 2 neoadjuvant trials for technically or oncologically unresectable HCCs ongoing in Japan: the LENS-HCC trial using lenvatinib and the RACB study using atezolizumab+bevacizumab. A longer follow-up may be needed, but the overall survival (OS) in resected cases seems much higher than that in unresectable cases. Recently, the Japan Liver Cancer Association (JLCA) and the Japanese Society of HPB Surgery (JSHPBS) created a joint working group on "so-called borderline resectable HCC". They obtained a Japanese consensus on this issue that has been published on the websites of JLCA and JSHPBS. The definition of resectability or borderline resectability provides a common language regarding advanced HCC for investigators and is a useful tool for future clinical trials.

15.
Cureus ; 16(5): e61305, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38947649

RESUMEN

Recurrent breast cancer presents clinical challenges due to its dynamic nature. Turning human epidermal growth factor receptor 2 (HER2) status from negative to positive upon recurrence is a rare but clinically significant phenomenon that can impact treatment decisions. We present the case of a 63-year-old female initially diagnosed with stage IIIA breast cancer, characterized as HER2-negative. However, upon recurrence eight years later, the patient exhibited HER2 conversion, indicating a positive status. Subsequent treatment adjustments were made based on this new HER2-positive status, leading to complete remission. HER2 conversion underscores the dynamic nature of tumor biology in recurrent breast cancer. This case highlights the importance of re-biopsy for accurate biomarker assessment and the necessity of personalized treatment strategies based on current molecular profiles. Understanding and recognizing HER2 conversion in recurrent breast cancer is crucial for optimizing patient outcomes and guiding clinical management decisions. Further research is warranted to elucidate the frequency and clinical implications of HER2 conversion in recurrent breast cancer.

16.
J Mov Disord ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950896

RESUMEN

Functional movement disorder(FMD) is a type of functional neurological disorder(FND) that is common, but often difficult to diagnose or manage. FMD can present as various phenotypes including tremor, dystonia, myoclonus, gait disorders and Parkinsonism. Conducting a clinical examination appropriate for the assessment of a patient with suspected FMD is important, and various diagnostic testing maneuvers may also be helpful. Treatment involving a multi-disciplinary team, either outpatient or inpatient, has been found to be most effective. Examples of such treatment protocols are also discussed in this review. While recognition and understanding of the disorder appears to have improved over the past few decades, as well as development of treatments, it is not uncommon for patients and physicians to continue to experience various difficulties when dealing with this disorder. In this review, I provide a practical overview of FMD and discuss how the clinical encounter itself can play a role in patients' acceptance of the diagnosis. Updates on recent neuroimaging studies that aid in the understanding of the pathophysiology are also discussed.

17.
Mol Ecol ; : e17453, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953291

RESUMEN

The major histocompatibility complex (MHC) multigene family encodes key pathogen-recognition molecules of the vertebrate adaptive immune system. Hyper-polymorphism of MHC genes is de novo generated by point mutations, but new haplotypes may also arise by re-shuffling of existing variation through intra- and inter-locus gene conversion. Although the occurrence of gene conversion at the MHC has been known for decades, we still have limited understanding of its functional importance. Here, I took advantage of extensive genetic resources (~9000 sequences) to investigate broad scale macroevolutionary patterns in gene conversion processes at the MHC across nearly 200 avian species. Gene conversion was found to constitute a universal mechanism in birds, as 83% of species showed footprints of gene conversion at either MHC class and 25% of all allelic variants were attributed to gene conversion. Gene conversion processes were stronger at MHC-II than MHC-I, but inter-specific variation at both MHC classes was explained by similar evolutionary scenarios, reflecting fluctuating selection towards different optima and drift. Gene conversion showed uneven phylogenetic distribution across birds and was driven by gene copy number variation, supporting significant role of inter-locus gene conversion processes in the evolution of the avian MHC. Finally, MHC gene conversion was stronger in species with fast life histories (high fecundity) and in long-distance migrants, likely reflecting variation in population sizes and host-pathogen coevolutionary dynamics. The results provide a robust comparative framework for understanding macroevolutionary variation in gene conversion at the avian MHC and reinforce important contribution of this mechanism to functional MHC diversity.

18.
Adv Sci (Weinh) ; : e2403197, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38946671

RESUMEN

Modifying the coordination or local environments of single-, di-, tri-, and multi-metal atom (SMA/DMA/TMA/MMA)-based materials is one of the best strategies for increasing the catalytic activities, selectivity, and long-term durability of these materials. Advanced sheet materials supported by metal atom-based materials have become a critical topic in the fields of renewable energy conversion systems, storage devices, sensors, and biomedicine owing to the maximum atom utilization efficiency, precisely located metal centers, specific electron configurations, unique reactivity, and precise chemical tunability. Several sheet materials offer excellent support for metal atom-based materials and are attractive for applications in energy, sensors, and medical research, such as in oxygen reduction, oxygen production, hydrogen generation, fuel production, selective chemical detection, and enzymatic reactions. The strong metal-metal and metal-carbon with metal-heteroatom (i.e., N, S, P, B, and O) bonds stabilize and optimize the electronic structures of the metal atoms due to strong interfacial interactions, yielding excellent catalytic activities. These materials provide excellent models for understanding the fundamental problems with multistep chemical reactions. This review summarizes the substrate structure-activity relationship of metal atom-based materials with different active sites based on experimental and theoretical data. Additionally, the new synthesis procedures, physicochemical characterizations, and energy and biomedical applications are discussed. Finally, the remaining challenges in developing efficient SMA/DMA/TMA/MMA-based materials are presented.

19.
Mol Biol Evol ; 41(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38959451

RESUMEN

Meiotic recombination is a fundamental feature of sexually reproducing species. It is often required for proper chromosome segregation and plays important role in adaptation and the maintenance of genetic diversity. The molecular mechanisms of recombination are remarkably conserved across eukaryotes, yet meiotic genes and proteins show substantial variation in their sequence and function, even between closely related species. Furthermore, the rate and distribution of recombination shows a huge diversity within and between chromosomes, individuals, sexes, populations, and species. This variation has implications for many molecular and evolutionary processes, yet how and why this diversity has evolved is not well understood. A key step in understanding trait evolution is to determine its genetic basis-that is, the number, effect sizes, and distribution of loci underpinning variation. In this perspective, I discuss past and current knowledge on the genetic basis of variation in recombination rate and distribution, explore its evolutionary implications, and present open questions for future research.


Asunto(s)
Variación Genética , Meiosis , Recombinación Genética , Meiosis/genética , Animales , Evolución Molecular , Evolución Biológica
20.
Heliyon ; 10(11): e32557, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38961985

RESUMEN

Background/purpose: Recently, a group of universal single-shade resin-based composites (RBCs) has been developed to simplify the process of shade selection. Excellent mechanical and physical properties are crucial for the ultimate success and clinical longevity of restorations. Therefore, evaluating the properties of the single-shaded RBCs is imperative. This study aimed to determine the flexural strength (FS) and degree of conversion (DC) of universal single-shade RBCs. Materials and methods: In this study, four commercial RBCs were used; three universal single-shade RBCs; Omnichroma (OC), Charisma® Diamond ONE (CD), and Vittra APS Unique (VU), and a conventional nanohybrid composite Filtek™ Z250 XT (FT) which was used as a control. Sixty composite beams and 40 composite discs were used for FS and DC, respectively. A universal test machine with a three-point bending test was used to measure the FS, whereas the DC was measured using a Fourier-transform infrared spectrometer (FTIR). Three fractured specimens from each resin composite group were qualitatively analyzed using scanning electron microscopy. Results: ANOVA was used to compare the mean values of FS and DC among the four RBCs (OC, CD, VU, and FT). Highly significant differences were observed in the mean FS and DC values (F = 673.043, p < 0.001 and F (=782.4, p < 0.0001), respectively. The highest FS was observed in the CD group, followed by FT and VU groups; the lowest value was observed in the OC group. In addition, a statistically significant difference was identified in DC values. The highest DC value was observed in VU, followed by OC and CD, and the lowest DC value was observed in FT. Conclusion: Universal single-shade RBCs demonstrated a good FS, except for OC, which exhibited a significantly low FS. The DC of the universal single-shade RBCs was higher than that of the conventional nanohybrid composite restorative material.

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