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Abstract Chemical looping combustion of SO2-containing syngas with various fabricated iron-calcium oxygen carriers was studied to comprehend the sulfurization and desulfurization of oxygen carriers during combustion. Experimental results indicated calcium-iron oxygen carriers fabricated with CaO:Fe2O3 weight ratio of 3:7 and calcined at 800°C (CaFe-378) was suitable for chemical looping combustion of syngas. CaFe2O4 was noticed to be the dominant crystalline phase in CaFe-378 even after 10 redox operations. Reduction kinetics for chemical looping combustion of both H2 or CO in syngas with CaFe-378 were adequately described by the 2-dimension diffusion model. The activation energies of H2 and CO with CaFe-378 were determined to be 35.4 kJ mol−1 and 46.0 kJ mol−1, respectively. Calcium sulfide (CaS) was generated during the chemical looping combustion of SO2-containing syngas with CaFe-378. CaS was further oxidized to CaSO4 on the surface of CaFe-378 during air regeneration, which might inhibit the complete regeneration of iron oxides. Satisfactory regeneration of sulfurized oxygen carriers was accomplished by introducing hydrogen after the air-regeneration because of the reduction of calcium sulfate to calcium oxide.

Abstract In an aging society, quality of life improvement is emerging as an important issue, and as implants are accepted as the core of oral rehabilitation treatment, competition for leadership in developing related technologies is intensifying. In this trend, unlike what is evident in the literature, the patent landscape shows the status of industrial-based technology development. A database analysis of a total of 32,237 dental implant patents shows improvements in technology, diverse geographical characteristics, and new advances toward technological convergence in this field. Technologically, dental implant technology has shown a tendency to develop from conventional implant materials and surface treatment technologies to new material technologies making use of substances such as pure zirconium and tantalum or software technologies related to diagnosis and prognosis. Regionally, dental implant technology, which was developed mainly in Europe and the Unites States in the past, is growing explosively in East Asian countries accompanied by the recent growth of the Asian market. In summary, dental implant technology seems to be developing while trying to converge with various technological areas based on the local market environment. Therefore, it is necessary to develop a new dental implant material technology that is highly applicable to the development of hybrid information/communication technology and is suitable for a new manufacturing method. Our study may provide important information to help basic and translational researchers and their financial supporters set their research directions in advancing the development of dental implants.

Abstract Iron-based oxygen carriers supported on alumina or alumina/titania were fabricated and evaluated for chemical looping combustion of isopropanol (IPA). Hydrogen is the major combustible gas generated by IPA decomposition prior to combustion with oxygen carriers at temperatures above 800°C. Nearly complete combustion (above 95%) of IPA was achieved for experiments conducted with fabricated Fe2O3/Al2O3 and Fe2O3/Al2O3/TiO2 operated at lower inlet IPA flow rates. Carbon deposition during the chemical looping combustion of IPA was minimized using Fe2O3/Al2O3/TiO2 as an oxygen carrier. The reduction of Fe2O3/Al2O3 and Fe2O3/Al2O3/TiO2 by hydrogen was markedly increased with increasing inlet hydrogen concentration (5–20%), and was not obviously influenced by operating temperature (875–925°C). According to the shrinking core model, the mass transfer coefficients (kg) of Fe2O3/Al2O3 and Fe2O3/Al2O3/TiO2 reduction with H2 were found to be 0.22 and 0.24 mm s−1, while the effective diffusion diffusivity (De) of Fe2O3/Al2O3 oxygen carriers was more easily depended on the oxygen carrier conversion. The higher reduction conversions obtained for experiments conducted with Fe2O3/Al2O3/TiO2 because it can be further reduced to FeO and Fe; comparing to those with Fe2O3/Al2O3, which is primarily reduced to FeO. Hydrogen molecules are found to diffuse more easily through the FeO product-layer on Fe2O3/Al2O3 than the FeO/Fe product-layer on Fe2O3/Al2O3/TiO2.

Abstract Fe2O3/Al2O3 and Fe2O3/TiO2/Al2O3 oxygen carriers were fabricated and evaluated for chemical looping hydrogen generation (CLHG) using a TGA system and a fixed-bed reactor. Oxygen carriers were converted to around 33% in a fixed-bed reactor to ensure uniform reduction. The reduced oxygen carrier was tested for steam generation, where in all cases Fe2O3/Al2O3 displayed a better conversion than Fe2O3/TiO2/Al2O3. It was found that increasing the reaction temperature from 800 to 850 °C had little effect for either oxygen carrier, but a further increase to 900°C resulted in an increased steam conversion. A higher steam flow rate caused a lower overall steam conversion but a higher H2 production. A higher feed rate of reduced oxygen carrier let to a higher steam conversion up to a rate of 18.4 and 14.9 g min−1 for Fe2O3/Al2O3 and Fe2O3/TiO2/Al2O3, respectively. A final comparison was performed with up to 50 redox cycles, where Fe2O3/Al2O3 showed superior reactivity in the first cycles but ended at a conversion of 54.6% with Fe2O3/TiO2/Al2O3 ending at a conversion of 64.6%.

BackgroundIt is well known that recommendations from electronic medication alerts are seldom accepted or acted on by users. Key factors affecting the effectiveness of medication alerts include system usability and alert design. Thus, human factors principles that apply knowledge of human capabilities and limitations are increasingly used in the design of health technology to improve the usability of systems. ObjectiveThis study aims to evaluate a newly developed evidence-based self-assessment tool that allows the valid and reliable evaluation of computerized medication alerting systems. This tool was developed to be used by hospital staff with detailed knowledge of their hospital’s computerized provider order entry system and alerts to identify and address potential system deficiencies. In this initial assessment, we aim to determine whether the items in the tool can measure compliance of medication alerting systems with human factors principles of design, the tool can be consistently used by multiple users to assess the same system, and the items are easy to understand and perceived to be useful for assessing medication alerting systems. MethodsThe Tool for Evaluating Medication Alerting Systems (TEMAS) was developed based on human factors design principles and consisted of 66 items. In total, 18 staff members recruited across 6 hospitals used the TEMAS to assess their medication alerting systems. Data collected from participant assessments were used to evaluate the validity, reliability, and usability of the TEMAS. Validity was assessed by comparing the results of the TEMAS with those of prior in-house evaluations. Reliability was measured using Krippendorff α to determine agreement among assessors. A 7-item survey was used to determine usability. ResultsThe participants reported mostly negative (n=8) and neutral (n=7) perceptions of alerts in their medication alerting system. However, the validity of the TEMAS could not be directly tested, as participants were unaware of any results from prior in-house evaluations. The reliability of the TEMAS, as measured by Krippendorff α, was low to moderate (range 0.26-0.46); however, participant feedback suggests that individuals’ knowledge of the system varied according to their professional background. In terms of usability, 61% (11/18) of participants reported that the TEMAS items were generally easy to understand; however, participants suggested the revision of 22 items to improve clarity. ConclusionsThis initial assessment of the TEMAS allowed the identification of its components that required modification to improve usability and usefulness. It also revealed that for the TEMAS to be effective in facilitating a comprehensive assessment of a medication alerting system, it should be completed by a multidisciplinary team of hospital staff from both clinical and technical backgrounds to maximize their knowledge of systems.

Abstract Background Accumulating evidence suggests that tobacco smoking affects the susceptibility to and severity of chronic periodontitis. Epigenetics may explain the role of smoking in the development and progress of periodontal disease. In this study, we performed transcriptomic and methylomic analyses of non-periodontitis and periodontitis-affected gingival tissues according to smoking status. Methods Human gingival tissues were obtained from 20 patients, including non-smokers with and without periodontitis (n = 5 per group) and smokers with and without periodontitis (n = 5 per group). Total RNA and genomic DNA were isolated, and their quality was validated according to strict standards. The Illumina NextSeq500 sequencing system was used to generate transcriptome and methylome datasets. Results Comprehensive analysis, including between-group correlation, differential gene expression, DNA methylation, gene set enrichment, and protein-protein interaction, indicated that smoking may change the transcription and methylation states of extracellular matrix (ECM) organization-related genes, which exacerbated the periodontal condition. Conclusions Our results suggest that smoking-related changes in DNA methylation patterns and subsequent alterations in the expression of genes coding for ECM components may be causally related to the increased susceptibility to periodontitis in smokers as they could influence ECM organization, which in turn may have an effect on disease characteristics.

Periodontal disease is a major public health issue, and various periodontal therapies have been performed to regenerate periodontal tissues. The periodontium is a complex structure composed of specialized tissues that support the teeth, and most periodontal surgeries are invasive procedures, including a resection of the gingiva or the alveolar bone. The periodontal wound healing process is slightly different from cutaneous wound healing and is similar to fetal healing, being almost scar-free. The aim of this review article is to provide an overview of periodontal wound healing and discuss various surgical and pharmaceutical approaches to achieve stable wound healing and improve the treatment outcomes. In addition, detrimental and limiting factors that induce a compromised prognosis are discussed, along with the perspective and future direction for successful periodontal tissue regeneration.

The oral microbiome is an important part of the human microbiome. The oral cavity has the second largest microbiota after the intestines, and its open structure creates a special environment. With the development of technology such as next-generation sequencing and bioinformatics, extensive in-depth microbiome studies have become possible. They can also be applied in the clinical field in terms of diagnosis and treatment. Many microbiome studies have been performed on oral and systemic diseases, showing a close association between the two. Understanding the oral microbiome and host interaction is expected to provide future directions to explore the functional and metabolic changes in diseases, and to uncover the molecular mechanisms for drug development and treatment that facilitate personalized medicine. The aim of this review was to provide comprehension regarding research trends in oral microbiome studies and establish the link between oral microbiomes and systemic diseases based on the latest technique of genome-wide analysis.

TiO2 nanotube arrays (TNTs) were modified with copper indium sulfide (Cu/In/S) by successive ionic layer adsorption and reaction (SILAR) method. The field-emission scanning electron microscopy and X-ray photoelectron spectroscopy analysis demonstrated the presence of copper indium sulfide nanoparticles on the surface of the modified TNTs. The Cu/In/S-modified TNTs exhibited higher photocurrent density and photocatalytic activity than plain TNTs. The concentration of sulfur precursor was found to be an important factor on the composition of modified Cu/In/S films by SILAR. Some composition deviations were observed on the stoichiometry of the Cu/In/S-modified TNTs, which evidently affected the electrochemical characteristics of the modified TNTs. Experiments using the modified TNTs of composition close to the stoichiometric ratio of CuInS2 usually delivered higher photocatalytic decomposition of gaseous isopropyl alcohol in air streams and exhibited better stability during operation.

Ultrasonic regeneration of activated carbon loaded with isopropyl alcohol (IPA) was studied. IPA adsorption was performed batchwise at varying solution pH. Adsorption was optimal at solution pH 7, which was closest to the point of zero charge of the activated carbon (6.7). Ultrasonic regeneration was performed on IPA-loaded activated carbon with three factors being tested: ultrasonic intensity, solution temperature and ethanol addition. Regeneration efficiency increased with ultrasonic intensity up to 32.4 W/cm2. A higher intensity led to a higher desorption but damaged the activated carbon, shown by a decrease in the particle size of activated carbon. The regeneration efficiency increased with solution temperature primarily because desorption is endothermic and because the surface tension and viscosity of a solution are reduced with increasing temperature, promoting cavitation bubble production. Ethanol addition increased regeneration efficiency up to 10%, as ethanol reduces tensile stress, facilitating cavitation bubble generation. At 15% and above, regeneration decreases, possibly due to coalescence of bubbles into larger, more stable bubbles. Under optimal parameters, the regeneration efficiency was 83%, which dropped to 64% after four regeneration cycles.

Material is a crucial factor for the restoration of the tooth or periodontal structure in dentistry. Various biomaterials have been developed and clinically applied for improved periodontal tissue regeneration and osseointegration, especially in periodontology and dental implantology. Furthermore, the biomimetic approach has been the subject of active research in recent years. In this review, the most widely studied biomaterials (bone graft material, barrier membrane, and growth or differentiation factors) and biomimetic approaches to obtain optimal tissue regeneration by making the environment almost similar to that of the extracellular matrix are discussed and specifically highlighted.

This study aimed to histologically and histomorphometrically evaluate osseointegration following simultaneous implant placement and maxillary sinus augmentation. Three retrospective human cases are described in which implants were placed at the maxillary sinus site augmented with deproteinized bovine bone mineral (DBBM) and later retrieved due to implant fracture after 5 to 8 years of occlusal loading. The removed implants with bone were processed for histologic evaluation, and bone-to-implant contact (BIC), bone area (BA), and mirror-image bone area (MIBA) were measured. Mature lamella bone was mainly observed, and some unabsorbed grafted bone particles remained in all cases. The measured values of BIC, BA, and MIBA in the three consecutive threads with the highest values were 86.0% to 91.2%, 65.8% to 91.9%, and 73.0% to 90.4%, respectively, and there were no signs of inflammation. Within the limits of this study, these cases demonstrate successful bone formation after maxillary sinus bone augmentation with DBBM and simultaneous implant placement. [ABSTRACT FROM AUTHOR]

Abstract Background The cost of labeling to collect training data sets using deep learning is especially high in medical applications compared to other fields. Furthermore, due to variances in images depending on the computed tomography (CT) devices, a deep learning based segmentation model trained with a certain device often does not work with images from a different device. Methods In this study, we propose an efficient learning strategy for deep learning models in medical image segmentation. We aim to overcome the difficulties of segmentation in CT images by training a VNet segmentation model which enables rapid labeling of organs in CT images with the model obtained by transfer learning using a small number of manually labeled images, called SEED images. We established a process for generating SEED images and conducting transfer learning a model. We evaluate the performance of various segmentation models such as vanilla UNet, UNETR, Swin-UNETR and VNet. Furthermore, assuming a scenario that a model is repeatedly trained with CT images collected from multiple devices, in which is catastrophic forgetting often occurs, we examine if the performance of our model degrades. Results We show that transfer learning can train a model that does a good job of segmenting muscles with a small number of images. In addition, it was confirmed that VNet shows better performance when comparing the performance of existing semi-automated segmentation tools and other deep learning networks to muscle and liver segmentation tasks. Additionally, we confirmed that VNet is the most robust model to deal with catastrophic forgetting problems. Conclusion In the 2D CT image segmentation task, we confirmed that the CNN-based network shows better performance than the existing semi-automatic segmentation tool or latest transformer-based networks.

Introduction and Objectives: The short-term mortality of severe alcoholic-associated hepatitis (SAH) is high, but there are no effective treatments to improve short-term mortality other than corticosteroids. This study investigated the effects of adding rifaximin to standard treatment in patients with SAH. Material and Methods: In this randomized controlled open-label trial, patients with SAH (Maddrey's discriminant function≥32) were randomized to the rifaximin or control group. Patients were simultaneously treated with corticosteroid or pentoxifylline as standard treatment for 4 weeks. Randomization was stratified by SAH treatment. Results: A total of 50 patients were enrolled in this study (29 in the control group and 21 in the rifaximin group). The mean Model for End-stage Liver Disease (MELD) scores were 24.4 and 27.5 in the control and rifaximin groups, respectively (P = 0.106). There were no significant differences in 6-month Liver Transplantation (LT)-free survival rate between the two groups (P = 0.502). When stratified by SAH treatment, there was no significant difference in 6-month LT-free survival rate between the control and rifaximin treatment groups (P = 0.186 in the corticosteroid group and P = 0.548 in the pentoxifylline group). There were no significant differences in the occurrence of liver-related complications between the two groups (all Ps>0.05). The MELD score was the only independent factor for 6-month LT-free survival (hazard ratio 1.188, 95 % confidence interval 1.094-1.289, P