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Ahoud Jazzar,1 Rawan Gadi,2 Mona Rajeh,2 Hebah AlDehlawi,1 Sana Alhamed,1 Tahani Badeeb3 1Department of Oral Diagnostic Sciences, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Dental Public Health, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia; 3Department of Prosthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi ArabiaCorrespondence: Ahoud Jazzar, Email ojazzar@kau.edu.saIntroduction: This study aimed to investigate how dental students at King Abdulaziz University Faculty of Dentistry transitioned from pre-clinical to clinical instruction and how this change affected their learning outcomes. Understanding this transition was crucial to identify the challenges faced by students and the support they required.Methods: A mixed-methods approach was utilized, combining qualitative insights from focus group discussions with quantitative data from surveys. Focus groups gathered detailed student experiences regarding their transition, while surveys measured workloads, anxiety levels, and perceptions of clinical competence.Results: The results showed that students have a lot of difficulties because of their heavier workloads, higher levels of anxiety, and the need for better integration of academic knowledge with practical abilities. Concerns over clinical competence and the necessity of improving communication with patients and healthcare teams are other characteristics of the transition phase. The findings highlighted how important structured support networks are for reducing transition-related stress and improving students’ readiness for clinical duties. These networks include peer mentorship, orientation programs, and customized curriculum modifications.Discussion: The study emphasized the value of early exposure to clinical settings and the inclusion of soft skill development in the curriculum, such as empathy and communication. The research advocated for comprehensive reforms in dental education, emphasizing the need for a holistic approach that addresses both the academic and emotional well-being of students. Dental faculties can contribute to the development of more competent and self-assured dental practitioners by improving support systems and incorporating practical experiences earlier in the educational timeline.Keywords: dental education, transition experiences, pre-clinical to clinical, mixed-methods approach, student challenges, support systems, curriculum design, learning outcomes, clinical competence

Graphene aerogels hold huge promise for the development of high-performance pressure sensors for future human-machine interfaces due to their ordered microstructure and conductive network. However, their application is hindered by the limited strain sensing range caused by the intrinsic stiffness of the porous microstructure. Herein, an anisotropic cross-linked chitosan and reduced graphene oxide (CCS-rGO) aerogel metamaterial is realized by reconfiguring the microstructure from a honeycomb to a buckling structure at the dedicated cross-section plane. The reconfigured CCS-rGO aerogel shows directional hyperelasticity with extraordinary durability (no obvious structural damage after 20 000 cycles at a directional compressive strain of ≤0.7). The CCS-rGO aerogel pressure sensor exhibits an ultrahigh sensitivity of 121.45 kPa-1, an unprecedented sensing range, and robust mechanical and electrical performance. The aerogel sensors are demonstrated to monitor human motions, control robotic hands, and even integrate into a flexible keyboard to play music, which opens a wide application potential in future human-machine interfaces.

Background: Silver nanotechnology is widely applied in industry and medicine, with an increased likelihood of environmental and food contamination. Aim: This study aimed to explore the adverse effects of orally administering silver nanoparticles (AgNPs) to pregnant or lactating female rats on adults and the development of their offspring. Methods: Forty female albino rats were used to assess the immediate impacts of AgNPs in two separate experiments. The experimental group received 1 mL of AgNPs, dissolved in deionized water, at doses of 0, 50, and 100 mg/kg of body weight from the 6th to the 15th day of gestation in pregnant albino rats. After a 20-day gestation period, euthanasia was performed on the female rats, followed by a gross examination post-dissection. Results: The feti were preserved in ethyl alcohol and Poin's solution for the identification of skeletal and visceral malformations. It was noticed that feti of dams that received AgNPs showed teratogenicities such as delayed ossification and deletion of bones or ribs. Notably, dams showed necrosis and satellitosis with evidence of behavioral alteration. While rats' pups showed only brain edema and no behavioral changes. Conclusion: AgNPs at a dose of 50 or 100 mg/kg induced teratogenic effect in terms of delayed ossification, abnormal limb formation, and brain edema in rat pups, however induced necrosis and satellitosis in dam rats. Hence, greater emphasis should be placed on preventing exposure to Ag-NPs, especially among pregnant females. [Open Vet J 2024; 14(8.000): 1999-2006]

Organic circularly polarized luminescence (CPL)-active molecular emitters featuring dynamic propeller-like luminophores were prepared in one step from cyclic(alkyl)(amino) carbenes (CAACs). These molecules exhibit through-space arene-arene π-delocalization and rapid intramolecular inter-system crossing (ISC) in line with their helical character.

BackgroundHalitosis, a socially and psychologically impactful condition often resulting from oral or systemic issues, is exacerbated by factors like aging, poor oral hygiene, and dietary choices. This study aimed to investigate the association between halitosis and stress by measuring salivary cortisol levels and the Cohen's Perceived Stress Scale (CPSS).MethodsA cross-sectional study of 40 participants was conducted using questionnaires and clinical measurements to assess halitosis and stress levels. Saliva samples were collected and analyzed for cortisol using ELISA. Participants’ stress was assessed with the Cohen's Perceived Stress Scale Questionnaire (CPSS-10) questionnaire, and halitosis was measured with a Halimeter and self-assessment questionnaire. Clinical measurements included Plaque Index (PI) and the Decayed, Missing, and Filled Teeth (DMFT) score.ResultsForty subjects were split into a halitosis group (mean age 30.75 ± 10.15) and group with no halitosis (mean age 26 ± 5.3). Objective measures confirmed higher halitosis scores (3.70 ± 0.73) in the halitosis group vs. the second group (2.60 ± 1.67). Compared with the group with no halitosis, the halitosis group exhibited significantly (p

The emerging interests in high-performance biocomposites grows significantly driven by their superior environmental sustainability. This study proposes a unique biocomposite strategy by implementing an acetic and ball-milled treatment to disrupt the bamboo cell wall structure, thereby facilitating further processing by effectively increasing the active sites and specific surface area in the bamboo fiber. The fibers are subsequently carboxymethylated to introduce carboxyl groups which facilitate physical bonding between the fibers and Mg2+ ions that are added to the system. These ions form metal-coordination bonds with the carboxyl groups, acting as ion bridges that significantly strengthen the inter-fiber bonding. The resulted biocomposite exhibits impressive mechanical properties, including a high tensile strength (94.24 MPa) and flexural strength (104.14 MPa), not only that, changes in elastic modulus also highlight changes in fiber bonding, the flexural modulus is 21.29 GPa and the tensile modulus is 7.01 GPa. Moreover, it maintains a low water uptake capacity of only 6.8 % despite being submerged for 12 h. The thermal conductivity and fire retardancy have also been improved. The synergic bonding ability between the cellulose and lignin in the fibers, coupled with the glue-free thermoforming process, enhances the material performance and renders it fully recyclable, thus reducing environmental pollution and providing cost-effective engineering materials to society.

Cyclic(alkyl)(amino)carbene (CAAC) ligands are found to perturb regioselectivity of the copper-catalyzed carboboration of terminal alkynes, favoring the less commonly observed internal alkenylboron regiosomer through an α-selective borylcupration step. A variety of carbon electrophiles participate in the reaction, including allyl alcohols derivatives and alkyl halides. The method provides a straightforward and selective route to versatile tri-substituted alkenylboron compounds that are otherwise challenging to access.

Regioselective hydrofunctionalization of alkynes represents a straightforward route to access alkenyl boronate and silane building blocks. In previously reported catalytic systems, high selectivity is achieved with a limited scope of substrates and/or reagents, with general solutions lacking. Herein, we describe a selective copper-catalyzed Markovnikov hydrofunctionalization of terminal alkynes that is facilitated by strongly donating cyclic (alkyl)(amino)carbene (CAAC) ligands. Using this method, both alkyl- and aryl-substituted alkynes are coupled with a variety of boryl and silyl reagents with high α-selectivity. The reaction is scalable, and the products are versatile intermediates that can participate in various downstream transformations. Preliminary mechanistic experiments shed light on the role of CAAC ligands in this process.

ABSTRACTOne of the major issues in healthcare today is antibiotic resistance. Antimicrobial peptides (AMPs), a subclass of host defense peptides, have been suggested as a viable solution for the multidrug resistance problem. Legume plants express more than 700 nodule-specific cysteine-rich (NCR) peptides. Three NCR peptides (NCR094, NCR888, and NCR992) were predicted to have antimicrobial activity using in silico AMP prediction programs. This study focused on investigating the roles of the NCRs in antimicrobial activity and antibiofilm activity, followed by in vitro toxicity profiling. Different variants were synthesized, i.e., mutated and truncated derivatives. The effect on the growth of Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA) was monitored post-treatment, and survived cells were counted using an in vitro and ex vivo killing assay. The antibiofilm assay was conducted using subinhibitory concentrations of the NCRs and monitoring K. pneumoniae biomass, followed by crystal violet staining. The cytotoxicity profile was evaluated using erythrocyte hemolysis and leukemia (K562) cell line toxicity assays. Out of the NCRs, NCR094 and NCR992 displayed mainly in vitro and ex vivo bactericidal activity on K. pneumoniae. NCR094 wild type (WT) and NCR992 eradicated K. pneumoniae at different potency; NCR094 and NCR992 killed K. pneumoniae completely at 25 and 50 µM, respectively. However, both peptides in the wild type showed negligible bactericidal effect on MRSA in vitro and ex vivo. NCR094 and its derivatives relatively retained the antimicrobial activity on K. pneumoniae in vitro and ex vivo. NCR992 WT lost its antimicrobial activity on K. pneumoniae ex vivo, yet the different truncated and mutated variants retained some of the antimicrobial role ex vivo. All the different variants of NCR094 had no effect on MRSA in vitro and ex vivo. Similarly, NCR992’s variants had a negligible bactericidal role on MRSA in vitro, yet the truncated variants had a significantly high bactericidal effect on MRSA ex vivo. NCR094.3 (cystine replacement variant) and NCR992.1 displayed significant antibiofilm activity more than 90%. NCR992.3 and NCR992.2 displayed more than 50% of antibiofilm activity. All the NCR094 forms had no toxicity, except NCR094.1 (49.38%, SD ± 3.46) and all NCR992 forms (63%–93%), which were above the cutoff (20%). Only NCR992.2 showed low toxicity on K562 (24.8%, SD ± 3.40), yet above the 20% cutoff. This study provided preliminary antimicrobial and safety data for the potential use of these peptides for therapeutical applications.IMPORTANCEThe discovery of new antibiotics is urgently needed, given the global expansion of antibiotic-resistant bacteria and the rising mortality rate. One of the initial lines of defense against microbial infections is antimicrobial peptides (AMPs). Plants can express hundreds of such AMPs as defensins and defensin-like peptides. The nodule-specific cysteine-rich (NCR) peptides are a class of defensin-like peptides that have evolved in rhizobial–legume symbioses. This study screened the antimicrobial activity of a subset of NCR sequences using online computational AMP prediction algorithms. Two novel NCRs, NCR094 and NCR992, with different variants were identified to exhibit antimicrobial activity with various potency on two problematic pathogens, K. pneumoniae and MRSA, using in vitro and ex vivo killing assays. Yet, one variant, NCR094.3, had no toxicity toward human cells and displayed antibiofilm activity, which make it a promising lead for antimicrobial drug development.

Misplacement of pericardiocentesis catheter in central veins is a rare complication that can be managed with several methods. In this case, we report a percutaneous image-guided plug-assisted management of a misplaced pericardiocentesis catheter into the inferior vena cava through a transhepatic tract successfully occluded. This minimally invasive technique was not previously described in this setting and had a favorable long-term outcome.

Selenium NMR has become a standard tool for scaling the π-accepting character of carbenes. Herein, we highlight that non-classical hydrogen bonding (NCHB), likely resulting from hyperconjugation, can play a significant role in the carbene-selenium 77 Se NMR chemical shift, thus triggering a non-linear behavior of the Se-Scale.

The popularity of NHCs in transition metal catalysis has prompted the development of chiral versions as electron-rich neutral stereodirecting ancillary ligands for enantioselective transformations. Herein we demonstrate that cyclic (alkyl)(amino)carbene (CAAC) ligands can also engage in asymmetric transformations, thereby expanding the toolbox of available chiral carbenes.

Langerhans cells, often referred to as the “macrophages of the skin”, are dendritic cells that normally reside in the epidermis and papillary dermis. Just like macrophages, they function as antigen-presenting cells that activate naive T cells. Certain mutations such as those involving the BRAF gene can cause unopposed production of Langerhans Cells, which is known as Langerhans Cell Histiocytosis (LCH). LCH triggers an inflammatory immune response that causes systemic manifestations such as fever and fatigue, as well as other manifestations depending on the affected organs. The pathogenesis behind LCH remains poorly understood. It is still unknown whether it is a neoplastic process or a reactive cancer-mimicking illness. Diagnosis of LCH is confirmed by biopsy, and treatment is largely dependent on the extent and severity of the disease. Common treatments include corticosteroids, excision, radiation, and chemotherapy. We present a case of a 1-year-old Saudi male with LCH.

In a volatile, uncertain, complex, and ambiguous environment, organizational change has been a central concern for capital project organizations, that continue to suffer from poor project performance in a growing industry. As such, capital project organizations must understand the changing environment and the factors driving change within their organizations to remain successful in a changing environment and adapt to change. To help the capital projects industry achieve successful organizational change efforts, this paper aims to 1) identify the external factors that are pushing capital project organizations to change and 2) investigate whether these factors impact organizations differently. To achieve the desired objective, a total of 22 PESTEL (political, economic, social, technological, environmental, and legal) factors were identified and validated with a group of 14 subject matter experts and defined via the context of literature. Then, the factors were evaluated via an online survey to understand whether they impact organizations differently based on their age maturity (including contemporary, transitional, and legacy organizations) and type of work (including owners, contractors, and service providers). Findings from this study can provide capital project practitioners and researchers with valuable insights needed to understand the external factors shaping change within the industry.

Background and Objective: High-flow pancreaticoduodenal artery (PDA) aneurysms secondary to celiac trunk occlusion or stenosis have a high risk of rupture. Embolization offers a less invasive alternative to surgery. We evaluated the effectiveness and safety of retrograde embolization via the superior mesenteric artery of high-flow PDA aneurysms without celiac trunk revascularization. Methods: This retrospective bicentric study included patients who underwent embolization of high-flow PDA aneurysms due to significant celiac trunk stenosis or occlusion. All patients underwent pre-interventional dynamic contrast-enhanced computed tomography. Retrograde embolization was performed using microcoils and/or liquid agents without celiac trunk revascularization. Follow up involved clinical and radiological assessment at one month. Technical and clinical success were evaluated, and complications were categorized as minor or major. Results: Twenty-three patients (mean age 65 ± 14 years; 52% male) were included. Emergency embolization was required in 12 patients (52%). The technical success rate was 100%. Patients were monitored for a median of 16 months. Clinical success was 87%. No hemorrhagic recurrences were observed. Minor complications occurred in two cases. One major complication involved splenic infarction due to glue migration, requiring splenectomy and intensive unit care admission. Conclusions: Retrograde embolization of high-flow PDA aneurysms is effective and safe without needing celiac trunk revascularization. [ABSTRACT FROM AUTHOR]

We propose a novel architecture, Transformer Dil-DenseUNet, designed to address the challenges of accurately segmenting stroke lesions in MRI images. Precise segmentation is essential for diagnosing and treating stroke patients, as it provides critical spatial insights into the affected brain regions and the extent of damage. Traditional manual segmentation is labor-intensive and error-prone, highlighting the need for automated solutions. Our Transformer Dil-DenseUNet combines DenseNet, dilated convolutions, and Transformer blocks, each contributing unique strengths to enhance segmentation accuracy. The DenseNet component captures fine-grained details and global features by leveraging dense connections, improving both precision and feature reuse. The dilated convolutional blocks, placed before each DenseNet module, expand the receptive field, capturing broader contextual information essential for accurate segmentation. Additionally, the Transformer blocks within our architecture address CNN limitations in capturing long-range dependencies by modeling complex spatial relationships through multi-head self-attention mechanisms. We assess our model's performance on the Ischemic Stroke Lesion Segmentation Challenge 2015 (SISS 2015) and ISLES 2022 datasets. In the testing phase, the model achieves a Dice coefficient of 0.80 ± 0.30 on SISS 2015 and 0.81 ± 0.33 on ISLES 2022, surpassing the current state-of-the-art results on these datasets. [ABSTRACT FROM AUTHOR]

Frame is a fundamental notion in the study of vector spaces; they offer redundancy and flexibility, which favor their application in various fields of mathematics. This article aims to collect important results of frames in Hibert pro-C∗-modules: Frame, ∗-frame, ∗-K-frame, g-frame, ∗-gframe, ∗-K-g-frame, operator frame, ∗-operator frame, ∗-K-operator frames. We also prove some new notions.