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Temperature-Programmed Reduction and Dispersive X-Ray Absorption Spectroscopy Studies of CeO<sub>2</sub>-Based Nanopowders for Intermediate-Temperature Solid-Oxide Fuel Cell Anodes

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Materials Sciences and Applications 2019年第10期10卷 631-642页

作者： marina S. Bellora Joaquí n Sacanell Cristiá n Huck-Iriart Analí a l. Soldati Susana A. larrondo Diego G. lamas CONICET/laboratorio de Cristalografía Aplicada Escuela de Ciencia y Tecnología Universidad Nacional de General San Martín San Martín Argentina Departamento de Física de la Materia Condensada Gerencia de Investigación y Aplicaciones Centro Atómico Constituyentes Comisión Nacional de Energía Atómica San Martín Argentina Instituto de Nanociencia y Nanotecnología (INN) CNEA-CONICET San Martín and San Carlos de Bariloche Argentina UNIDEF-CONICET-MINDEF Departamento de Investigaciones en Sólidos CITEDEF Villa Martelli Argentina Instituto de Investigación e Ingeniería Ambiental Universidad Nacional de General San Martín San Martín Argentina

In this work, we study the influence of the average crystallite size and dopant oxide on the reducibility of CeO2-based nanomaterials. Samples were prepared from commercial Gd2O3-, Sm2O3- and Y2O3-doped CeO2 powders by calcination at different temperatures ranging between 400°C and 900°C and characterized by X-ray powder diffraction, transmission electron microscopy and BET specific surface area. The reducibility of the samples was analyzed by temperature-programmed reduction and in situ dispersive X-ray absorption spectroscopy techniques. Our results clearly demonstrate that samples treated at lower temperatures, of smallest average crystallite size and highest specific surface areas, exhibit the best performance, while Gd2O3-doped ceria materials display higher reducibility than Sm2O3- and Y2O3-doped CeO2.

关键词： Crystallite Size CeO2-Based Nanomaterials Sm2O3

Application of Magnetic Particle Imaging to Pulmonary Imaging Using Nebulized Magnetic Nanoparticles

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Open Journal of Medical Imaging 2015年第2期5卷 49-55页

作者： Kohei Nishimoto Atsushi Mimura marina Aoki Natsuo Banura Kenya Murase Department of Medical Physics and Engineering Division of Medical Technology and Science Faculty of Health Science Graduate School of Medicine Osaka University Osaka Japan

Purpose: To investigate the feasibility of applying magnetic particle imaging (MPI) to pulmonary imaging using nebulized magnetic nanoparticles (MNPs) and to quantify the mucociliary clearance in the lung, using small animal experiments. Materials and Methods: Intrapulmonary administration of MNPs was performed in seven-week-old male ICR (Institute of Cancer Research) mice (n = 8) using a nebulized microsprayer connected to a high-pressure syringe containing 50 μl of MNPs (500 mM Resovist®). We imaged the lungs using our MPI scanner 2.5 hours, 1 day, 3 days, and 7 days after the intrapulmonary administration of MNPs. The average MPI value was calculated by drawing a region of interest (ROI) on the lungs by taking the threshold value for extracting the contour as 20% of the maximum MPI value within the ROI. The MPI value was defined as the pixel value of the transverse image reconstructed from the third-harmonic signals. Mice were sacrificed immediately after the last MPI and X-ray CT studies on day 7, and 5 lobes of the lung in each mouse were extracted to confirm the accumulation of iron using Berlin blue staining. Results: We could visualize the distribution of MNPs in the lungs as positive contrast using MPI with use of nebulized MNPs. The presence of iron in the lung was confirmed by Berlin blue staining. The average MPI value decreased with time and tended to saturate. The clearance rate was calculated to be 0.505 day−1 from the time course of the average MPI value in the lungs. Conclusion: Our preliminary results suggest that MPI can be applied to pulmonary imaging by nebulizing MNPs and can be useful for quantifying the mucociliary clearance in the lung.

关键词： Magnetic Particle Imaging Pulmonary Imaging Nebulized Magnetic Nanoparticles Animal Experiments

laparoscopic Small Bowel Resection of Gastrointestinal Stromal Tumour after Angiographic Diagnosis and Successful Embolization

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International Journal of Clinical Medicine 2011年第5期2卷 640-643页

作者： marina Garcés Albir Roberto Martí Fernando lópez Mozos Norberto Cassinello Fernández Jorge Guijarro Rosaleny Joaquín Ortega Serrano 不详

Gastrointestinal stromal tumors (GIST) account for 2% of all tumors of the digestive tract. They are most frequently located in the stomach followed by the small intestine and most often present with mucosal ulceration and erosion associated with gastrointestinal bleeding. Bleeding from the small intestine can be difficult to diagnose and angiography becomes a useful diagnostic and therapeutic procedure in these patients. We present a case of a GIST located in the ileum which presented with a lower gastrointestinal bleeding (lGIB). The patient was stabilized by performing an arteriography and selective embolization of the bleeding point, followed by elective surgery.

关键词： Gastrointestinal Stromal Tumor Gastrointestinal Blleeding Angiography Selective Embolization

过流式UV/H_(2)O_(2)反应器中阿特拉津降解动力学的测定及模拟评估

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环境工程学报 2021年第3期15卷 982-991页

作者：詹露梦李文涛李梦凯 JENSEN marina Bergen 张淼强志民中国科学院生态环境研究中心饮用水科学与技术重点实验室北京100085 哥本哈根大学地球科学和自然资源管理学院腓特烈堡丹麦1985 中国科学院大学中丹学院北京100049 江西理工大学土木与测绘工程学院赣州341000

紫外高级氧化工艺在降解去除水中微量有机污染物方面具有良好的应用前景,已有大量相关基础研究在实验室序批式反应器内完成,然而,在实际工程中采用的过流式反应器中的不同水流形态可能会对反应动力学和工艺效率产生影响。为此,采用过流... 详细信息

紫外高级氧化工艺在降解去除水中微量有机污染物方面具有良好的应用前景,已有大量相关基础研究在实验室序批式反应器内完成,然而,在实际工程中采用的过流式反应器中的不同水流形态可能会对反应动力学和工艺效率产生影响。为此,采用过流式UV/H_(2)O_(2)反应器降解水中阿特拉津(ATZ),分别考察了H_(2)O_(2)浓度、反应器内径对ATZ降解效率和工艺经济性的影响,同时评估了稳态假设(SSA)模型在过流式UV/H_(2)O_(2)反应器中应用的可行性。结果表明:过流式反应器中UV/H_(2)O_(2)工艺对ATZ有着良好的去除效果,降解过程基本符合拟一级反应动力学(R^(2)>0.95);虽然反应器内流态并非完全混合,SSA模型仍可准确预测反应器中目标污染物的降解,模拟和实验结果相对偏差绝大多数不超过20%;在考察的H_(2)O_(2)浓度范围内,随着浓度的增加,不同反应器中ATZ的降解速率均逐渐增大,特别在H_(2)O_(2)浓度为0.2 mmol·l^(−1)时,内径为35 mm的反应器中ATZ降解速率常数达到5.8×10^(−2)s^(−1),是单独UV辐照下的4倍以上。由于平均紫外强度的变化,增大反应器内径将导致ATZ基于时间的降解速率常数的降低,但对基于紫外剂量的速率常数影响不大。此外,E_(EO)分析结果表明,增加H_(2)O_(2)浓度和增大反应器内径均可以降低ATZ去除的单位能耗。

关键词： UV/H_(2)O_(2) 过流式反应器稳态假设模型降解速率单位能耗

Composition and Molecular Identification of Bacterial Community in Seawater Desalination Plants

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Advances in Microbiology 2019年第10期9卷 863-876页

作者： Pilar Garcia-Jimenez marina Carrasco-Acosta Carlos Enrique Payá Irina Alemá n ló pez Juana Rosa Betancort Rodrí guez José Alberto Herrera Meliá n Department of Biology Universidad de Las Palmas de Gran Canaria Campus de Tafira Las Palmas Spain Department of Water Instituto Tecnológico de Canarias Playa de Pozo Izquierdo Las Palmas Spain Department of Chemistry Universidad de Las Palmas de Gran Canaria Campus de Tafira Las Palmas Spain

Biofouling is an important problem for reverse osmosis (RO) membrane manufacturers. Bacteria are mainly involved in generating fouling and obturating RO membranes. Insights into biofilm bacteria composition could help prevent biofouling, reduce the cost of using RO-fouling membranes and guarantee safe water. Culture-dependent and independent techniques were then performed in order to identify bacteria associated with RO membranes. Bacteria cultures described the presence of six pure colonies, four of which were identified through API testing. Based on 16s rRNA gene analysis, a predominant bacterium was identified and annotated as Sphingomonas sp. The 16s rRNA gene clone library, on the other hand, showed that the bacterium, Pseudomonas marincola, accounted for nearly 30% of the clone library, while the rest of bacteria were chimeras (62%) and non-representative species (3%). In conclusion, culture-dependent and independent approaches showed that two dominant bacteria were commonly observed in RO desalination membranes.

关键词： Biofouling Bacteria 16s rRNA Reverse Osmosis Membrane Pseudomonas sp. Sphingomonas sp.

Pharmacokinetic Study and Toxicity of leukovir: A New Combined Drug for the Treatment of Multiple Sclerosis

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Advances in Biological Chemistry 2022年第1期12卷 1-15页

作者： Elena N. Kalinichenko Irina V. Ponteleeva marina B. Golubeva State Scientific Institution “Institute of Bioorganic Chemistry of the National Academy of Sciences of Belarus” Minsk Belarus

leukovir, an enteric-coated tablet, is the original drug product for internal use. The well-known nucleosides cladribine and ribavirin are the active ingredients of the drug product leukovir. Pharmacokinetic parameters of the drug product for the internal use of leukovir active ingredients have been established. The cladribine half-absorption period was t1/2a = 49.5 h, C0 = 276.4 μg/ml, Cmax = 6.0 μg/ml. Distribution and accumulation parameters (Vd, Vss and AUC) have indicated that the drug distribution between the blood cells and blood plasma takes place in the same way, irrespective of the dosage form. Cladribine half-life period is t1/2e = 0.62 hours. The molecule total clearance and average lifetime in the body in the case of subcutaneous drug administration are approximately the same. Ribavirin is characterized by a half-absorption period of t1/2a = 0.71 h, C0 = 115.6 μg/ml and Cmax = 75.5 μg/ml. Ribavirin total volume of distribution (Vd = 1.3 l/kg) and stationary volume of distribution (Vss = 1.64 l/kg) were practically similar to leukovir when administered subcutaneously. The AUC value = 504.2 μg h/ml, which is 2.5 times less than that in the case of drug form administration. leukovir was regarded as slightly toxic in an acute toxicity study. The risk of cumulation for this drug product is low.

关键词： leukovir Cladribine Ribavirin Multiple Sclerosis Pharmacokinetics Toxicity

Natural Radiation Dose and Geomagnetic Effect

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Journal of Geoscience and Environment Protection 2018年第4期6卷 172-180页

作者： Branko Vukovic marina Poje Sovilj Vanja Radolic Igor Miklavcic Josip Planinic Department of Physics University of OsijekOsijekCroatia

Earth keeps getting bombarded by high-energy particles that originate in the outer space and in Sun. Cosmic radiation in Earth’s atmosphere consists of a photon and directly ionizing component and a neutron component. Charged particles of cosmic radiation are deflected by the geomagnetic field that is more expressed at the equator than near the poles. Photon radiation was measured by Radiameter ESM FH 40G-l10 at 26 main meteorological stations in all parts of Croatia. The correlation between the photon dose rate and latitude was examined, as well as multiple correlations for the photon dose, latitude and altitude. The obtained positive correlation coefficients were statistically significant. The neutron component of the cosmic radiation was measured by series of nuclear track-etched detectors, at the same meteorological stations during one year period. The dependence of the neutron dose rate on the altitude was found and the associated equation of the linear regression was derived. Relation between the values of neutron dose N and altitude h, showed significant dependence of the neutron dose on altitude. However, the correlation of neutron dose and geographic (geomagnetic) latitude was not statistically significant, probably due to a small range of geographic latitudes for the measuring stations in Croatia.

关键词： Cosmic Radiation Track Etch Detector Geomagnetic Effect Dose Rate

Projections of Precipitation Changes in Two Vulnerable Regions of São Paulo State, Brazil

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American Journal of Climate Change 2017年第2期6卷 268-293页

作者： Iracema F. A. Cavalcanti lucí H. Nunes José A. Marengo Jorge l. Gomes Virginia P. Silveira marina S. Castellano Center of Weather Forecasting and Climate Studies/National Institute for Space Science (CPTEC/INPE) Cachoeira Paulista S.P. Brazil State University of Campinas (UNICAMP) Cachoeira Paulista S.P. Brazil National Center for Monitoring and Early Warning of Natural Disasters (CEMADEN) S&atilde o José dos Campos S.P. Brazil

Weather and climate extremes are part of the natural variability. However, the frequency and intensity of precipitation extremes have increased in the globe following the global warming. Extreme precipitation impacts such as landslides and flooding with implications to vulnerability and adaptation are discussed for two regions of the state of S?o Paulo: the Metropolitan Region of Campinas and the Metropolitan Region of the Baixada Santista, located in southeastern South America. Simulations and projections obtained from four integrations of the Regional Eta model are analyzed to investigate the model behavior during the period of 1961-1990 and the projections within the period of 2011-2100. Uncertainties are discussed based on the standard deviation among the model spread. The projections show precipitation increase in the Metropolitan Region of Campinas during DJF for the near and distant future, while there are more uncertainties in the other seasons. In the Metropolitan Region of Baixada Santista, the precipitation increase is projected to all seasons, except JJA, when there is higher uncertainty. Daily rainfall indices suggest an increase of precipitation during the rainy days, but a reduction in the number of rainy days in both locations. The projections show a reduction of light rains and an increase of heavy rains at both regions. The model identifies the South Atlantic Convergence Zone and frontal systems as precipitation patterns associated with extremes in the two locations. The results can be useful for adaptation actions, since the regions are highly populated and have high vulnerabilities.

关键词： Climate Change Precipitation Extremes Vulnerable Regions Precipitation Indices Regional Model

Pneumo-CT assessing response to neoadjuvant therapy in esophageal cancer: Imaging-pathological correlation

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World Journal of Gastrointestinal Oncology 2013年第12期5卷 222-229页

作者： marina Ulla Ernestina Gentile Ezequiel levy Yeyati Maria l Diez Demetrio Cavadas Ricardo D Garcia-Monaco Pablo R Ros Department of Radiology Hospital Italiano de Buenos Aires

Pneumo-computed tomography (PnCT) is a technique primarily developed and used to study stenotic lesions of the esophagus, gastroesophageal junction and stom-ach for pre-surgical planning. It helps to define both upper and lower borders of neoplasms located in the aforementioned areas. It achieves maximum lumen distension with CO2 highlighting thickened areas of the esophageal wall, thus allowing an accurate quantifica-tion of their extents. Although there are other alterna-tives for distension (oral contrast agents, water and ef-fervescent granules), they may be suboptimal. Patients with locally advanced esophageal cancer have a dismal prognosis despite surgical resection. Therefore, neo-adjuvant treatment strategies using radiation therapy and chemotherapy were developed to improve sur-vival. Neoadjuvant therapy improves esophageal tumor prognosis in a substantial proportion of patients, and the use of imaging techniques is mandatory to detect their response. PnCT combined with virtual endoscopy and multiplanar reconstruction enhances morphologic details in esophageal cancer, and thus would allow animproved assessment of response to neoadjuvant treat-ment. Therefore, more information could be provided to assess the efficacy of pre-surgical treatment. We de-scribe the potential use of PnCT to assess the response to neoadjuvant therapy in esophageal cancer with an imaging pathologic correlation.

关键词： Esophagus Cancer 64-multidetector com-puted tomography Neoadjuvant treatment Assess-ment response