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Evaluation of the effectiveness of panoramic radiography in impacted mandibular third molars on deep learning models developed with findings obtained with cone beam computed tomography
No full text<p>ObjectiveThe aim of this study is to determine the contact relationship and position of impacted mandibular third molar teeth (IMM3) with the mandibular canal (MC) in panoramic radiography (PR) images using deep learning (DL) models trained with the help of cone beam computed tomography (CBCT) and DL to compare the performances of the architectures.MethodsIn this study, a total of 546 IMM3s from 290 patients with CBCT and PR images were included. The performances of SqueezeNet, GoogLeNet, and Inception-v3 architectures in solving four problems on two different regions of interest (RoI) were evaluated.ResultsThe SqueezeNet architecture performed the best on the vertical RoI, showing 93.2% accuracy in the identification of the 2nd problem (contact relationship buccal or lingual). Inception-v3 showed the highest performance with 84.8% accuracy in horizontal RoI for the 1st problem (contact relationship-no contact relationship), GoogLeNet showed 77.4% accuracy in horizontal RoI for the 4th problem (contact relationship buccal, lingual, other category, or no contact relationship), and GoogLeNet showed 70.0% accuracy in horizontal RoI for the 3rd problem (contact relationship buccal, lingual, or other category).ConclusionThis study found that the Inception-v3 model showed the highest accuracy values in determining the contact relationship, and SqueezeNet architecture showed the highest accuracy values in determining the position of IMM3 relative to MC in the presence of a contact relationship.</p>
Differential TLR2 and TLR4 mediated inflammatory and apoptotic responses in asymptomatic and symptomatic<i> Leptospira</i><i> interrogans</i> infections in canine uterine tissue
No full text<p>Leptospirosis is major zoonotic disease with global implications, affecting both domestic animals and humans. It is caused by Leptospira interrogans (L. interrogans), which can damage multiple organs, including the kidneys, liver, testes, and uterus. Despite this, L. interrogans can also persist asymptomatically in tissues, akin to nonpathogenic strains. The mechanisms driving asymptomatic infections remain poorly understood. This study investigated the role of L. interrogans in asymptomatic infection within the uterine tissue of canines, focusing on the differential expression of Toll-like receptors (TLRs)2 and 4 and their roles in inflammatory and apoptotic pathways. We hypothesized that TLR2 and TLR4 coexpression is crucial for eliciting inflammation and apoptosis, whereas TLR4 alone might be insufficient. Our findings revealed that in symptomatic infections, both TLR2 and TLR4 are coexpressed, leading to markedly elevated levels of the proinflammatory cytokines IL-10, IL-1 beta, TNF-alpha, and IL-6. This enhanced inflammatory response is further evidenced by increased CD4 expression, indicating robust T helper cell activation. In contrast, asymptomatic infections are characterized by exclusive TLR4 expression, with inflammatory markers remaining at baseline levels. Additionally, we observed that L. interrogans induces apoptosis in symptomatic animals through TLR2 and TLR4 mediated activation of Caspase 8 and Caspase 3. These findings illustrate that L. interrogans drives both inflammation and apoptosis via the combination of TLR2 and TLR4 actions. When only TLR4 is activated, the immune response is insufficient, resulting in an asymptomatic disease course. This study provides novel insights into the differential roles of TLR receptors in leptospirosis, offering potential directions for targeted therapeutic strategies.</p>
Gold nanoparticles decorated FOLFIRINOX loaded liposomes for synergistic therapy of pancreatic cancer
No full text<p>Pancreatic cancer is predicted to be the second highest cause of cancer deaths by 2030, with a mortality rate of 98 % and a 5-year survival rate of only 4-8 %. FOLFIRINOX which consists of four main ingredients has shown superior efficacy in treating patients with pancreatic cancer compared to other agents and combinations. However, toxicities have prevented full-dose use of FOLFIRINOX. In this study, we present the design of a liposome nanosystem that enables the sequential release of a drug combination that is called FOLFIRINOX using lipid-based nanosystem synergistic chemo/photothermal therapy approaches. The co-eccentric liposome allowed us to locate the drug molecules in different locations giving us the flexibility to release them in a selected order. Core liposome (L2) has a melting temperature of 53.63 degrees C, it was decorated by gold nanoparticle (L2@AuNP) to bring photothermal responsiveness. The outer liposome structure had a lower melting temperature, which facilitated the sequential release process. The efficacy of photothermal therapy for nanosystem was calculated. The results indicate that coating L2@AuNP nanostructure with L1 liposomes improves efficacy by stabilizing gold nanoparticles. FOLFIRINOX components are encapsulated in a concentric liposome structure according to the order of administration into the body. The concentric liposome structure enables the sequential release of multiple drugs due to the varying phase transition temperatures of the liposomes. The cytotoxic effect of these formulations was evaluated on Panc-1 pancreatic cancer cells; the lowest cell viability was obtained in 4 Liposome(L) under 5 min NIR irradiation. Combination therapy has a higher therapeutic efficacy (70.45 %) when compared to chemotherapy and photothermal therapy used separately. The study's results show the potential of combination therapies to improve therapeutic outcomes, providing a promising path for future research and clinical application.</p>
Removal of emerging organic micropollutants from real hospital wastewater by modified ultrafiltration membranes
No full text<p>Membrane biofouling, characterized by the adherence and growth of microorganisms on the surface of a membrane, poses a significant challenge to the effectiveness of membrane bioreactor (MBR) technology. Enhancing anti-biofouling characteristics, particularly the prevention of bacterial adhesion to the membrane, is crucial for the sustained operation of MBR over the long term. One of the most popular methods for enhancing these characteristics is surface modification. In this study, two distinct concentrations of 150 mu M and 300 mu M of BisBAL -a chelate derived from bismuth with strong antibacterial action on a variety of microorganisms- were added to polymeric membrane solutions. Using these solutions, flat sheet (FS) and hollow fiber (HF) membranes were produced via the phase inversion method to examine their removal capabilities for micropollutants in a real hospital wastewater. Caffeine (CAF), Paracetamol (APAP) and Ciprofloxacin (CPFX) were observed as target micropollutants during a pilot-scale MBR operation. The chemical modification of the membranes enhanced the characteristics of the membrane material. Pure water flux values increased while contact angles were decreased in modified membranes When compared to bare membranes, BisBAL-added modified membranes were observed to reject CAF, APAP and CPFX more effectively. When 150 and 300 mu M BisBAL is added to FS and HF membranes, the rejection efficiencies of CAF and APAP reached their maximums, exceeding 80 %. Remarkably, CPFX rejection in the case of FS membranes added with 300 mu M reached about 30 %, whereas it surpasses 80 % in the case of HF membranes added with the same concentration. The mechanism behind the rejection of micropollutants by the membranes was determined to be adsorption. In addition to their enhanced resistance to biofouling, the new potential of these modified membranes was also demonstrated. The results suggested that membranes modified with 300 mu M BisBAL were particularly optimal for the pilot-scale MBR operations in the future, with HF membranes generally outperforming FS membranes.</p>
Bimodal functionality of highly conductive nanostructured silver film towards improved performance of photosystem I-based graphene photocathode
No full text<p>We present the novel design of photosystem I (PSI)-based biosolar cell, whereby conductive transparent electrode materials, such as ITO or FTO, are replaced with glass covered with silver island film. This nanostructured metallic layer combines high electric conductance with enhancing the absorption efficiency of the PSI biocatalyst via the plasmonic effect. We demonstrate strong enhancement of the photocurrent generated in the biohybrid electrode composed of oriented layers of PSI reaction centers due to plasmonic interactions of the PSI fluorophores and redox centres with the conductive silver island film.</p>
Multifunctional theranostic glyconanoprobes for synergistic eradication of breast cancer
No full text<p>Theranostic agents hold great promise for personalized medicine by combining diagnostic and therapeutic functions. Herein, two novel multifunctional theranostic glyconanoprobes targeting breast cancer were engineered for synergistic dual chemo-gene therapy and triple chemo-gene-photothermal therapy. Upconversion nanoparticles (UCNPs) were prepared and coated with a Dox-loaded glycopeptide polymer (P-Dox) to form UCNP@P-Dox for improving stability. UCNP@MP-Dox equipped for triple therapy was prepared by combining UCNP@P-Dox with magnetic (Fe3O4, M) nanoparticles with photothermal properties. To regulate the expression of the anti-apoptotic Bcl-2 protein, both UCNP@P-Dox and UCNP@MP-Dox were loaded with anti-Bcl-2 siRNA. Impressive photothermal efficiency and good MRI contrast were demonstrated in preliminary evaluations. Moreover, the UCNP@P-Dox/siRNA nanoprobe for dual therapy was shown in preclinical studies to significantly increase anti-tumor efficacy. In vivo experiments in tumor-induced mice showed nanoprobe accumulation in tumors and enhanced antitumor efficacy with combinatorial therapy over Dox and siRNA alone. This study demonstrates the tumor-targeting capability of multifunctional theranostic glyconanoprobes, establishing chemo-gene synergy as a potent therapeutic strategy for breast cancer.</p>
Discovering prerequisite relations using large language models
No full text<p>Automatic detection of prerequisite relations between concepts in education has always been a challenging AI task for researchers. Identification of prerequisite relations enables students to study new subjects more effectively and systematically, while allowing instructors to better tailor their learning materials to students' needs. However, to accurately detect these relations, the AI system must understand the context and meaning behind each concept and how it relates to other concepts in the domain. This requires a deep understanding of the educational curriculum and the ability to analyze large amounts of text and data. Large language models (LLMs) are a recent innovation in AI. LLMs have the capability to understand and generate human-like text since they are trained on a vast amount of text from the internet, books, articles, and more. LLMs can also be fine-tuned to specialize in tasks such as document summarization, question answering, or detecting user sentiment in reviews. Fine-tuning is done with a smaller, task-specific dataset. In this work, we introduce strategies for fine-tuning LLMs to improve their capability to detect prerequisite relations between educational concepts. To the best of our knowledge, this is the first work that utilizes fine-tuned LLMs for prerequisite detection. Our evaluation results demonstrate that fine-tuned LLMs are effective models for prerequisite detection. Our fine-tuning process also facilitates the generation of explanations to shed light on the reasoning behind prerequisite relations. Datasets we generated and used in fine-tuning are made public for the research community. We hope our contributions can aid in organizing and presenting knowledge in education and serve as a foundation for future research in the field.</p>
Non-destructive health monitoring of glass fibre epoxy composites under fatigue loading using electrical resistance change method
No full text<p>This study investigates the effect of stress amplitude on the damage sensing characteristic of glass fibre reinforced (GFRP) composites under fatigue loading using the electrical resistance change (ERC) method. The electrical conductivity of GFRP composites was achieved by incorporating 0.3 wt.% multi-walled carbon nanotubes (MWCNTs) into epoxy resin by ultrasonication method. In-situ electrical resistance measurements during fatigue tests of MWCNT-filled GFRP (MWNCT/GFRP) composites were conducted at two different stress amplitudes, S = 0.6 and S = 0.5. The average stiffness losses at failure were observed as 28% and 25% for S = 0.6 and S = 0.5 respectively. The corresponding ERC ratios at failure were found as 153% and 59% for S = 0.6 and S = 0.5, respectively. A two-parameter Weibull analysis, based on the ERC ratios corresponding to 40%, 60%, 80%, and 100% (failure) fatigue life, was implemented to establish reliability curves at the two stress amplitudes. The ERC ratios at failure with a 95% reliability for S = 0.6 and S = 0.5 were determined as 64% and 23%, respectively. Finally, the remaining fatigue life and the stiffness loss of composite specimens at the ERC ratios corresponding to various Weibull reliability were found for both stress amplitudes.</p>
Effect of phase composition on thermal and electrical conductivity of additive-free silicon carbide ceramics
No full text<p>Dense (RD > 97%) silicon carbide ceramics without any sintering additives were prepared by freeze granulation of silicon carbide powders, annealing of granulated powders and subsequent densification by field assisted sintering technique (FAST) at 1900 degrees C. Thermal and electrical conductivity of prepared materials considering the mass fraction of SiC polytypes was investigated. Different ratio of alpha and beta silicon carbide has been achieved by adjusting dwell time during sintering. Thermal diffusivity, specific heat capacity, thermal conductivity, electrical conductivity, density, microstructure of additive-free SiC with various alpha/beta content has been investigated. The electrical conductivity of SiC ceramics decrease from 104 S/m to 8 S/m as a content of alpha-SiC increase from 63 % to 94 %. Opposite trend, when thermal diffusivity increased from 47.3 to 69.9 mm(2)/s as a content of alpha-SiC increase from 63 % to 94%, was observed. The highest thermal conductivity (lambda=165 W/m.K) among the SiC ceramics sintered at temperatures <= 1900 degrees C was achieved for additive-free SiC sintered at 1900 degrees C under vacuum for 80 minutes.</p>
In vitro and in vivo effects of commercial and environmental microplastics on <i>Unio delicatu</i>s
No full text<p>Microplastics (MPs) are ubiquitous pollutants in freshwater environments. In this study, freshwater mussels, Unio delicatus, were exposed to both environmental MPs (e-MP) and commercial MPs (c-MP) that include green fluorescent MP (gf-MP), polyethylene (c-PE) and polystyrene (c-PS) at environmental concentrations (5 mg/L and 50 mg/L) over duration of 7 and 30 days. According to in vivo experiment results, both e-MPs and c-MPs induced significant changes in the total hemocyte counts of mussels (p < 0.05). Exposure to high concentrations of e-MPs and c-MPs for 7 days led to decreased cellular glutathione levels in the mussels, while exposure to low concentrations of e-MPs and c-PS for 7 days resulted in increased advanced oxidation protein products (AOPP). Mussels exposed to high concentrations of e-MPs for 30 days exhibited decreases in both glutathione levels and AOPP values. Although no damage was observed in tissues other than gills and digestive gland, histopathological alterations were observed in these tissues following exposure to 50 mg/L c-MPs. Additionally, MPs were observed in the intestine tissues. In vitro experiments using the MTT assay showed no significant difference in cell viability between the MP-exposed group and the control group at tested concentrations, with no observed dose-response relationship (p > 0.05). Nevertheless, certain cells exhibited signs of cell death, such as disrupted cellular structures, condensed nuclei, and loss of cellular integrity. These observations were consistent with mechanical compression, indicating that physical contact with MPs may result in cell damage or death. These findings demonstrate that environmentally relevant concentrations of MPs have toxic effects on freshwater mussels and multiple parameters provide valuable insight for the evaluation of health risks of organisms.</p>