CCUS Activities in Korea and Introduction to the Korea CCUS Association

Axel Lemus 한국에너지기후변화학회 2023 한국에너지기후변화학회 학술대회 Vol.2023 No.5

Combination of Mn oxidation states improves the photocatalytic degradation of phenol with ZnAl LDH materials without a source of O₂ in the reaction system

Morales-Mendoza, Getsemani,Alvarez-Lemus, Mayra,Ló,pez, Rosendo,Tzompantzi, Francisco,Adhikari, Rajesh,Lee, Soo Wohn,Torres-Martí,nez, Leticia M.,Gó,mez, Ricardo Elsevier 2016 CATALYSIS TODAY - Vol.266 No.-

<P><B>Abstract</B></P> <P>Mn-doped Zn/Al layered double hydroxides (LDH) materials were synthesized by the co-precipitation method. X-ray diffraction (XRD) analysis confirmed the polytype structure of LDH materials obtained as well as the successful incorporation of Mn into the structure. Atomic absorption spectroscopy (AAS) and energy dispersive X-ray spectroscopy (EDS) studies showed a well dispersion of Mn and a good correlation between the nominal and experimental composition. Scanning electron microscopy (SEM) revealed the formation of grains close to 1μm length. Energy band gap (Eg) of the solids determined by UV–vis diffuse reflectance spectroscopy (DRS) showed high photoresponse in the ultraviolet (UV) region, which was increased with Mn incorporation into the LDH structure. The LDH materials were evaluated in the photocatalytic degradation of phenol in aqueous medium, under UV radiation with and without O<SUB>2</SUB> source in the reaction system. The results showed that the O<SUB>2</SUB> is not an effective electron scavenger as usually occurs in TiO<SUB>2</SUB> photocatalyst. The Mn effect in the photocatalytic activity was notably marked in anaerobic condition however in aerobic or anaerobic conditions the presence of Mn increases the photoactivity. The phenol mineralization reached in anaerobic conditions was 95% (1.5ppm) of the initial concentration (30ppm) and it is maintained constant after 6h of radiation while in aerobic conditions the TOC reaches only 55% (13.5ppm). The role of Mn as charges separator is discussed and a suitable mechanism is proposed. This study shows that the Mn doped-Zn/Al LDH materials could be a promising photocatalysts under anaerobic conditions for the removal of phenol from aqueous medium.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ZnAl LDH rebuilt in phenol solution have not capacity to open the interlayer space. </LI> <LI> A source of O<SUB>2</SUB> have not influence in the phenol photooxidation with ZnAl LDH. </LI> <LI> Mn doped-ZnAl LDH increases the optical properties of absorption. </LI> <LI> The role as electron and hole trap of Mn takes advantage to separate charge. </LI> <LI> The Mn incorporation in ZnAl LDH materials improves the photocatalytic activity. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

CO₂ 해외저장소 확보를 위한 한국-네덜란드 고갈가스전 활용 해양 CCUS 저장 설계 및 설비 구축 비용 절감 기술

정봉용(Bong-Yong JEONG),정은수(Eunsoo JUNG),Axel Lemus,한아름(AhReum Han) 한국에너지기후변화학회 2023 한국에너지기후변화학회 학술대회 Vol.2023 No.5

Calcium-doped zinc oxide nanocrystals as an innovative intracanal medicament: a pilot study

de Souza Gabriela Leite,Magalhães Thamara Eduarda Alves,Freitas Gabrielle Alves Nunes,Lemus Nelly Xiomara Alvarado,Barbosa Gabriella Lopes de Rezende,Silva Anielle Christine Almeida,Moura Camilla Chri 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.4

Objectives This study investigated the cytotoxicity, radiopacity, pH, and dentinal tubule penetration of a paste of 1.0% calcium-doped zinc oxide nanocrystals (ZnO:1.0Ca) combined with propylene glycol (PRG) or polyethylene glycol and propylene glycol (PEG-PRG). Materials and Methods The pastes were prepared by mixing calcium hydroxide [Ca(OH)2] or ZnO:1.0Ca with PRG or a PEG-PRG mixture. The pH was evaluated after 24 and 96 hours of storage in deionized water. Digital radiographs were acquired for radiopacity analysis and bubble counting of each material. The materials were labeled with 0.1% fluorescein and applied to root canals, and images of their dentinal tubule penetration were obtained using confocal laser scanning microscopy. RAW264.7 macrophages were placed in different dilutions of culture media previously exposed to the materials for 24 and 96 hours and tested for cell viability using the MTT assay. Analysis of variance and the Tukey test (α = 0.05) were performed. Results ZnO:1.0Ca materials showed lower viability at 1:1 and 1:2 dilutions than Ca(OH)2 materials (p < 0.0001). Ca(OH)2 had higher pH values than ZnO:1.0Ca at 24 and 96 hours, regardless of the vehicle (p < 0.05). ZnO:1.0Ca pastes showed higher radiopacity than Ca(OH)2 pastes (p < 0.01). No between-material differences were found in bubble counting (p = 0.0902). The ZnO:1.0Ca pastes had a greater penetration depth than Ca(OH)2 in the apical third (p < 0.0001). Conclusions ZnO:1.0Ca medicaments presented higher penetrability, cell viability, and radiopacity than Ca(OH)2. Higher values of cell viability and pH were present in Ca(OH)2 than in ZnO:1.0Ca. Objectives This study investigated the cytotoxicity, radiopacity, pH, and dentinal tubule penetration of a paste of 1.0% calcium-doped zinc oxide nanocrystals (ZnO:1.0Ca) combined with propylene glycol (PRG) or polyethylene glycol and propylene glycol (PEG-PRG). Materials and Methods The pastes were prepared by mixing calcium hydroxide [Ca(OH)2] or ZnO:1.0Ca with PRG or a PEG-PRG mixture. The pH was evaluated after 24 and 96 hours of storage in deionized water. Digital radiographs were acquired for radiopacity analysis and bubble counting of each material. The materials were labeled with 0.1% fluorescein and applied to root canals, and images of their dentinal tubule penetration were obtained using confocal laser scanning microscopy. RAW264.7 macrophages were placed in different dilutions of culture media previously exposed to the materials for 24 and 96 hours and tested for cell viability using the MTT assay. Analysis of variance and the Tukey test (α = 0.05) were performed. Results ZnO:1.0Ca materials showed lower viability at 1:1 and 1:2 dilutions than Ca(OH)2 materials (p < 0.0001). Ca(OH)2 had higher pH values than ZnO:1.0Ca at 24 and 96 hours, regardless of the vehicle (p < 0.05). ZnO:1.0Ca pastes showed higher radiopacity than Ca(OH)2 pastes (p < 0.01). No between-material differences were found in bubble counting (p = 0.0902). The ZnO:1.0Ca pastes had a greater penetration depth than Ca(OH)2 in the apical third (p < 0.0001). Conclusions ZnO:1.0Ca medicaments presented higher penetrability, cell viability, and radiopacity than Ca(OH)2. Higher values of cell viability and pH were present in Ca(OH)2 than in ZnO:1.0Ca.

Analysis of Compression and Permeability Behavior of Porous Ti6Al4V by Computed Microtomography

Luis Olmos,Didier Bouvard,Jose Luis Cabezas‑Villa,Jose Lemus‑Ruiz,Omar Jiménez,Dante Arteaga 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.3

Porous materials were developed as a good alternative to replace different bones in the human body as they improve osseointegration,tissue ingrowth and simulate the mechanical properties of human bones. Such characteristics highly depend on thepore features and volume fraction. Samples with a pore volume fraction between 16 and 60% and a pore size distribution of100–500 μm were analyzed by computed microtomography. 3D images acquisition was performed at 10 μm pixel resolution,which permitted to observe the complete sample. Features like size, shape, orientation, connectivity and pore coordinationwere determined from the 3D image analysis. Compression behavior was evaluated by interrupted compression testing and,after that, new 3D images were acquired. In order to evaluate permeability, numerical simulations of flow throughout the3D images were carried out by using Avizo® software. It was found that shape and pore size distribution was similar in allsamples, showing good distribution of the pore formers inside the matrix. Full connectivity of pores was obtained with 32%volume fraction and above, and the coordination number follows the Artz model. The pores showed a radial orientation,which induces anisotropy in the flow properties. The compression showed two different behaviors, pore closing and porecoalescence. Values of permeability match with those reported for bones as well as the anisotropy in the radial and verticaldirections. It is concluded that the sample with 60 vol% of pores could be consider to be used for bone implants.

Daidzein–Estrogen Interaction in the Rat Uterus and Its Effect on Human Breast Cancer Cell Growth

Leonardo Gaete,Andrei N. Tchernitchin,Rodrigo Bustamante,Joan Villena,Igor Lemus,Manuel Gidekel,Gustavo Cabrera,Paola Astorga 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.12

Sex hormone replacement therapy provides several advantages in the quality of life for climacteric women. However, estrogen-induced cell proliferation in the uterus and mammary gland increases the risk of cancer development in these organs. The lower incidence of mammary cancer in Asian women as compared with Western women has been attributed to high intake of soy isoflavones, including genistein. We have previously shown that genistein induces an estradiol-like hypertrophy of uterine cells, but does not induce cell proliferation, uterine eosinophilia, or endometrial edema. It also inhibits estradiol-induced mitosis in uterine cells and hormone-induced uterine eosinophilia and endometrial edema. Nevertheless, genistein stimulates growth of human breast cancer cells in culture; therefore, it is not an ideal estrogen for use in hormone replacement therapy (HRD). The present study investigated the effect of another soy isoflavone, daidzein (subcutaneous, 0.066 mg/kg body weight), in the same animal model, and its effect on responses induced by subsequent treatment (1 h later) with estradiol-17β (E2; subcutaneous, 0.33 mg/kg body weight). In addition, we investigated the effects of daidzein (1 μg/mL) or E2 on the growth of human breast cancer cells in culture. Results indicate that daidzein stimulates growth of breast cancer cells and potentiates estrogen-induced cell proliferation in the uterus. We suggest caution for the use of daidzein or formulas containing this compound in HRD. Future research strategies should be addressed in the search for new phytoestrogens that selectively inhibit cell proliferation in the uterus and breast.

Use of Tumor Necrosis Factor Receptor (TNFR)-Knockout Mice to Probe the Mechanism of Chemically-Induced Asthma

Karol, Meryl H.,Matheson, Joanna M.,Lange, Robert W.,Lemus, Ranulfo,Luster, Michael I. The Korean Society of Toxicology Korea Environment 2001 Toxicological Research Vol.17 No.-

Toluene diisocyanate (TDI) is widely used in the manufacture of polyurethanes and is a recognized cause of occupational asthma. Although extensive investigations have been undertaken, the molecular mechanism(s) of the disease is still unclear. We hypothesized that inflammatory cytokines are required during both the sensitization and elicitation phases of the disease and have utilized TNF-R knock-out (KO) mice to address the hypothesis. Black C57 TNFR knock-out mice were exposed to TDI by sc injection and challenged by inhalation of 100 ppb TDI vapor. Control animals included: wild type C57 animals, sham-exposed animals that were challenged with TDI, and animals that were injected with anti-TNF antibodies prior to sensitization and again prior to challenge. Total IgE was increased in the knock-out animals compared with the wild type sensitized and challenged animals whereas TDI-specific IgG antibodies did not differ significantly in KO and wild type animals. There was less inflammation in the nares and trachea in KO animals compared with the wild type animals exposed to TD1 as well as less goblet cell hyperplasia and epithelial damage. Airway reactivity was assessed in animals treated with anti-TNF$\alpha$ antibody and found to be substantially reduced compared with that in sensitized and challenged animals. These results indicate that TNF$\alpha$ plays a role in the immunologic and physiologic responses and in airways inflammation in this animal model and suggests a role for TNF in occupational asthma due to TDI.

Genistein Selectively Inhibits Estrogen-Induced Cell Proliferation and Other Responses to Hormone Stimulation in the Prepubertal Rat Uterus

Leonardo Gaete,Andrei N. Tchernitchin,Rodrigo Bustamante,Joan Villena,Igor Lemus,Manuel Gidekel,Gustavo Cabrera,Omar Carrillo 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.12

Sex hormone replacement therapy helps improve quality of life in climacteric women. However, estrogeninduced cell proliferation in the uterus and mammary gland increases the risk for cancer in these organs. The lower incidence of mammary cancer in Asian women than in western women has been attributed to high intake of soy isoflavones, including genistein. Our previous work in the prepubertal rat uterus model showed that genistein (0.5 mg/kg body weight subcutaneously)caused an estradiol-like hypertrophy in myometrial and uterine luminal epithelial cells and an increase in RNA content in luminal epithelium; however, it did not induce cell proliferation, uterine eosinophilia, or endometrial edema. The present study investigated, in the same animal model, the effect of genistein administration (0.5 mg/kg body weight subcutaneously)before treatment with estradiol-17β (0.33 mg/kg body weight subcutaneously) on uterine responses that were not induced by genistein. Pretreatment with this phytoestrogen completely inhibited estradiol-induced mitoses in uterine luminal epithelium,endometrial stroma, and myometrium and partially inhibited estradiol-induced uterine eosinophilia and endometrial edema. These findings indicate that genistein protects against estrogen-induced cell proliferation in the uterus and suggest that future studies should investigate the possibility of using this agent to decrease the risk for uterine cancer after hormone replacement therapy in climacteric women.

Effects of different calcium-silicate based materials on fracture resistance of immature permanent teeth with replacement root resorption and osteoclastogenesis

de Souza Gabriela Leite,Freitas Gabrielle Alves Nunes,Ribeiro Maria Tereza Hordones,Lemus Nelly Xiomara Alvarado,Soares Carlos José,Moura Camilla Christian Gomes 대한치과보존학회 2023 Restorative Dentistry & Endodontics Vol.48 No.2

Objectives This study evaluated the effects of Biodentine (BD), Bio-C Repair (BCR), and mineral trioxide aggregate (MTA) plug on the fracture resistance of simulated immature teeth with replacement root resorption (RRR) and in vitro-induced osteoclastogenesis. Materials and Methods Sixty bovine incisors simulating immature teeth and RRR were divided into 5 groups: BD and BCR groups, with samples completely filled with the respective materials; MTA group, which utilized a 3-mm apical MTA plug; RRR group, which received no root canal filling; and normal periodontal ligament (PL) group, which had no RRR and no root canal filling. All the teeth underwent cycling loading, and compression strength testing was performed using a universal testing machine. RAW 264.7 macrophages were treated with 1:16 extracts of BD, BCR, and MTA containing receptor activator of nuclear factor-kappa B ligand (RANKL) for 5 days. RANKL-induced osteoclast differentiation was assessed by staining with tartrate-resistant acid phosphatase. The fracture load and osteoclast number were analyzed using 1-way ANOVA and Tukey’s test (α = 0.05). Results No significant difference in fracture resistance was observed among the groups (p > 0.05). All materials similarly inhibited osteoclastogenesis (p > 0.05), except for BCR, which led to a lower percentage of osteoclasts than did MTA (p < 0.0001). Conclusions The treatment options for non-vital immature teeth with RRR did not strengthen the teeth and promoted a similar resistance to fractures in all cases. BD, MTA, and BCR showed inhibitory effects on osteoclast differentiation, with BCR yielding improved results compared to the other materials. Objectives This study evaluated the effects of Biodentine (BD), Bio-C Repair (BCR), and mineral trioxide aggregate (MTA) plug on the fracture resistance of simulated immature teeth with replacement root resorption (RRR) and in vitro-induced osteoclastogenesis. Materials and Methods Sixty bovine incisors simulating immature teeth and RRR were divided into 5 groups: BD and BCR groups, with samples completely filled with the respective materials; MTA group, which utilized a 3-mm apical MTA plug; RRR group, which received no root canal filling; and normal periodontal ligament (PL) group, which had no RRR and no root canal filling. All the teeth underwent cycling loading, and compression strength testing was performed using a universal testing machine. RAW 264.7 macrophages were treated with 1:16 extracts of BD, BCR, and MTA containing receptor activator of nuclear factor-kappa B ligand (RANKL) for 5 days. RANKL-induced osteoclast differentiation was assessed by staining with tartrate-resistant acid phosphatase. The fracture load and osteoclast number were analyzed using 1-way ANOVA and Tukey’s test (α = 0.05). Results No significant difference in fracture resistance was observed among the groups (p > 0.05). All materials similarly inhibited osteoclastogenesis (p > 0.05), except for BCR, which led to a lower percentage of osteoclasts than did MTA (p < 0.0001). Conclusions The treatment options for non-vital immature teeth with RRR did not strengthen the teeth and promoted a similar resistance to fractures in all cases. BD, MTA, and BCR showed inhibitory effects on osteoclast differentiation, with BCR yielding improved results compared to the other materials.

Computed tomography-guided Gasserian ganglion interventions for cancer-related facial pain in patients with complex anatomy: Insights and recommendations

Ale Ismael González-Casarez1,Santamaría-Montaño Germán Gerardo,Plancarte-Sánchez Ricardo,Guillén-Núñez María Rocío,Juárez-Lemus Ángel Manuel,Hernández-Porras Berenice Carolina,Samano-García Marcela,Ro 대한마취통증의학회 2023 Anesthesia and pain medicine Vol.18 No.2

Background: The Gasserian ganglion is a well-known target for facial pain management, and patients with cancer present an anatomical challenge owing to tumor progression or treatment itself. Computed tomography (CT) is an alternative method for guiding these procedures.Methods: This was an observational retrospective analysis of patients with cancer-related facial pain who underwent CT-guided Gasserian ganglion interventions using local anesthetics, local anesthetics with steroids, phenol, and radiofrequency. Demographic, clinical, and procedure-related variables were collected from January 1, 2015, to December 30, 2018, at the National Cancer Institute. Data distribution was determined using the Kolmogorov–Smirnov test. A paired sample t-test (with a cut-off of P < 0.05 for statistical significance) was used for comparing outcome.Results: We observed a significant reduction in numerical rating scale (NRS) and douleur neuropathique 4 (DN4) scores from 7.6 ± 1.4 and 4.4 ± 1.4 to 3.2 ± 2.0 and 2.2 ± 1.4 points, respectively (P < 0.001). After the procedure, 70.8% of the patients were satisfied; 16.7% were very satisfied, and 12.5% were unsatisfied. No intra- or postoperative complications were observed. The most common neoplasms were head and neck tumors (83.3%).Conclusions: Our data suggest that CT guidance is an effective and safe option for managing cancer-related facial pain in patients with complex anatomy, resulting in a significant reduction in pain, high satisfaction rates, and no mechanical complications. Future research should aim to refine the role of CT guidance in multimodal pain management in this population.