26. |
- Bettegowda, Chetan, et al.
(författare)
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Detection of circulating tumor DNA in early- and late-stage human malignancies
- 2014
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Ingår i: Science Translational Medicine. - : American Association for the Advancement of Science (AAAS). - 1946-6234 .- 1946-6242. ; 6:224, s. 224ra24-
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Tidskriftsartikel (refereegranskat)abstract
- The development of noninvasive methods to detect and monitor tumors continues to be a major challenge in oncology. We used digital polymerase chain reaction-based technologies to evaluate the ability of circulating tumor DNA (ctDNA) to detect tumors in 640 patients with various cancer types. We found that ctDNA was detectable in >75% of patients with advanced pancreatic, ovarian, colorectal, bladder, gastroesophageal, breast, melanoma, hepatocellular, and head and neck cancers, but in less than 50% of primary brain, renal, prostate, or thyroid cancers. In patients with localized tumors, ctDNA was detected in 73, 57, 48, and 50% of patients with colorectal cancer, gastroesophageal cancer, pancreatic cancer, and breast adenocarcinoma, respectively. ctDNA was often present in patients without detectable circulating tumor cells, suggesting that these two biomarkers are distinct entities. In a separate panel of 206 patients with metastatic colorectal cancers, we showed that the sensitivity of ctDNA for detection of clinically relevant KRAS gene mutations was 87.2% and its specificity was 99.2%. Finally, we assessed whether ctDNA could provide clues into the mechanisms underlying resistance to epidermal growth factor receptor blockade in 24 patients who objectively responded to therapy but subsequently relapsed. Twenty-three (96%) of these patients developed one or more mutations in genes involved in the mitogen-activated protein kinase pathway. Together, these data suggest that ctDNA is a broadly applicable, sensitive, and specific biomarker that can be used for a variety of clinical and research purposes in patients with multiple different types of cancer.
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27. |
- Delbari, MT, et al.
(författare)
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Clinical Manifestations, Immunological Characteristics and Genetic Analysis of Patients with Hyper-Immunoglobulin M Syndrome in Iran
- 2019
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Ingår i: International archives of allergy and immunology. - : S. Karger AG. - 1423-0097 .- 1018-2438. ; 180:1, s. 52-63
-
Tidskriftsartikel (refereegranskat)abstract
- <b><i>Background:</i></b> Hyper-immunoglobulin M (HIGM) syndrome is a rare heterogeneous group of primary immunodeficiency disorders characterized by low or absent serum levels of IgG and IgA along with normal or elevated serum levels of IgM. <b><i>Methods:</i></b> Clinical and immunological data were collected from the 75 patients’ medical records diagnosed in Children’s Medical Center affiliated to Tehran University Medical Sciences and other Universities of Medical Sciences in Iran. Among 75 selected patients, 48 patients (64%) were analyzed genetically using targeted and whole-exome sequencing. <b><i>Results:</i></b> The ratio of male to female was 2.9:1. The median age at the onset of the disease, time of diagnosis, and diagnostic delay were 10.5, 50, and 24 months, respectively. Pneumonia and lower respiratory tract infections (61.3%) were the most common complications. Responsible genes were identified in 35 patients (72.9%) out 48 ge<i>netically</i> analyzed patients. <i>Cluster of differentiation 40 ligand</i> gene was the most mutated gene observed in 24 patients (68.5%) followed by <i>activation-induced cytidine deaminase</i> gene in 7 patients, <i>lipopolysaccharide-responsive and beige-like anchor</i> (1 patient), <i>nuclear factor-kappa-B essential modulator</i> (1 patient), <i>phosphoinositide-3-kinase regulatory subunit 1</i> (1 patient), and <i>nuclear factor kappa B subunit 1</i> (1 patient) genes. Nineteen (25.3%) patients died during the study period, and pneumonia was the major cause of death occurred in 6 (31.6%) patients. <b><i>Conclusion:</i></b> Physicians in our country should carefully pay attention to respiratory tract infections and pneumonia, particularly in patients with a positive family history. Further investigations are required for detection of new genes and pathways resulting in HIGM phenotype.
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28. |
- Wu, Lang, et al.
(författare)
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Identification of Novel Susceptibility Loci and Genes for Prostate Cancer Risk : A Transcriptome-Wide Association Study in over 140,000 European Descendants
- 2019
-
Ingår i: Cancer Research. - : AMER ASSOC CANCER RESEARCH. - 0008-5472 .- 1538-7445. ; 79:13, s. 3192-3204
-
Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association study-identified prostate cancer risk variants explain only a relatively small fraction of its familial relative risk, and the genes responsible for many of these identified associations remain unknown. To discover novel prostate cancer genetic loci and possible causal genes at previously identified risk loci, we performed a transcriptome-wide association study in 79,194 cases and 61,112 controls of European ancestry. Using data from the Genotype-Tissue Expression Project, we established genetic models to predict gene expression across the transcriptome for both prostate models and cross-tissue models and evaluated model performance using two independent datasets. We identified significant associations for 137 genes at P < 2.61 x 10(-6), a Bonferroni-corrected threshold, including nine genes that remained significant at P < 2.61 x 10(-6) after adjusting for all known prostate cancer risk variants in nearby regions. Of the 128 remaining associated genes, 94 have not yet been reported as potential target genes at known loci. We silenced 14 genes and many showed a consistent effect on viability and colony-forming efficiency in three cell lines. Our study provides substantial new information to advance our understanding of prostate cancer genetics and biology. Significance: This study identifies novel prostate cancer genetic loci and possible causal genes, advancing our understanding of the molecular mechanisms that drive prostate cancer.
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29. |
- Zakaria, A.K.M., Asgar, M.A., Ahmed, F.U., Yunus, S.M., Azad, A.K., Paranjpe, S.K., Das, A.
(författare)
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Studies of Mn0.5Cr0.5Fe2O4 ferrite by neutron diffraction at different temperatures in the range 768K ³ T ³ 13K
- 2002
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Ingår i: Indian Journal of Pure & Applied Physics. ; 40, s. 46-53
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Tidskriftsartikel (refereegranskat)
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30. |
- Abdalla, A. M., et al.
(författare)
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Nanomaterials for solid oxide fuel cells: A review
- 2018
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Ingår i: Renewable and Sustainable Energy Reviews. - : Elsevier BV. - 1879-0690 .- 1364-0321. ; 82, s. 353-368
-
Forskningsöversikt (refereegranskat)abstract
- Nanotechnology is utilized well in the development and improvement of the performance in Solid Oxide Fuel Cells (SOFCs). The high operating temperature of SOFCs (700–900 °C) has resulted in serious demerits regarding their overall performance and durability. Therefore, the operating temperature has been reduced to an intermediate temperature range of approximately 400–700 °C which improved performance and, subsequently, commercialized SOFCs as portable power sources. However, at reduced temperature, challenges such as an increase in internal resistance of the fuel cell components arise. Although, this may not be as serious as problems encountered at high temperature, it still significantly affects the performance of SOFCs. This review paper addresses the work of researchers in the application of nanotechnology in fabricating SOFCs through distinct methods. These methods have successfully omitted or at least reduced the internal resistance and showed considerable improvement in power density of the SOFCs at reduced temperatures.
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31. |
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32. |
- Afif, A., et al.
(författare)
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Advanced materials and technologies for hybrid supercapacitors for energy storage – A review
- 2019
-
Ingår i: Journal of Energy Storage. - : Elsevier BV. - 2352-152X. ; 25:October 2019
-
Forskningsöversikt (refereegranskat)abstract
- Supercapacitors have become the most significant energy conversion and storage system in recent renewable and sustainable nanotechnology. Due to its large energy capacity and supply with relatively short time and longer lifetime, supercapacitors breakthrough in advance energy applications. This review presents a comparative study of different materials, working principles, analysis, applications, advantages and disadvantages of various technologies available for supercapacitors. The aim of this article is to discuss the possibility of hybrid supercapacitor for the next generation of energy technology. The development of composite materials containing a wide range of active constituents (e.g., graphene, activated carbon, transition metals, metal oxides, perovskites and conducting polymers) by in-situ hybridization and ex-situ recombination is also discussed. This review consecrated largely the contribution of combining all materials (electrode and electrolyte) and their synthesis process and electrochemical performance. Enduringly, the potential issues and the perspectives for future research based on hybrid supercapacitors in energy applications are also presented.
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33. |
- Afif, A., et al.
(författare)
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Structural and electrochemical characterization of BaCe0.7Zr0.2Y0.05Zn0.05O3 as an electrolyte for SOFC-H
- 2016
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Ingår i: IOP Conference Series: Materials Science and Engineering. - 1757-8981 .- 1757-899X. ; 121:1
-
Konferensbidrag (refereegranskat)abstract
- As a potential electrolyte for proton-conducting solid oxide fuel cells (SOFC-Hs) and to get better protonic conductivity and stability, zinc doped BCZY material has been found to be promising. In this study, we report a new composition of proton conductors BaCe0.7Zr0.2Y0.05Zn0.05O3 (BCZYZn5) which was investigated using XRD, SEM and conductivity measurements. Rietveld refinement of the XRD data revel a cubic perovskite structure with Pm-3m space group. BaCe0.7Zr0.2Y0.05Zn0.05O3 shows cell parameter a = 4.3452(9) Å. Scanning electron microscopy images shows that the grain sizes are large and compact which gives the sample high density and good protonic conductivity. The total conductivity in wet atmosphere is significantly higher than that of dry condition and the conductivity was found to be 0.276 × 10-3 Scm-1 and 0.204 × 10-3 Scm-1 at 600°C in wet and dry Ar, respectively. This study indicated that perovskite electrolyte BCZYZn5 is a promising material for the next generation intermediate temperature solid oxide fuel cells (IT-SOFCs).
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34. |
- Afif, A., et al.
(författare)
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Structural study and proton conductivity in BaCe0.7Zr0.25-xYxZn0.05O3 (x=0.05, 0.1, 0.15, 0.2 & 0.25)
- 2016
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Ingår i: International Journal of Hydrogen Energy. - : Elsevier BV. - 0360-3199. ; 41:27, s. 11823-11831
-
Tidskriftsartikel (refereegranskat)abstract
- Solid oxide fuel cell (SOPC) has been considered to generate power represented by conductivity. Zinc doped Barium Cerium Zirconium Yttrium oxide (BCZYZn) has been found to offer high protonic conductivity and high stability as being electrolyte for proton conducting SOFCs. In this study, we report a new series of proton conducting materials, BaCe0.7Zr0.25-xYxZn0.05O3 (x = 0.05, 0.1, 0.15, 0.2 and 0.25). The materials were synthesized by solid state reaction route and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal expansion, particle size and impedance spectroscopy (IS). Rietveld analysis of the XRD data reveal a cubic perovskite structure with Pm-3m space group up to composition x = 0.15. For x = 0.15 and 0.20, the materials have structural phase change to orthorhombic in the Pbnm space group. Scanning electron microscopy images show high density materials. Thermal expansion measurements show that the thermal expansion coefficient is in the range 10.0-11.0 x 10(-6)/degrees C. Impedance spectroscopy shows higher ionic conduction under wet condition compared to dry condition. Y content of 25% (BCZYZn25) exhibits highest conductivity of 1.84 x 10(-2) S/cm in wet Argon. This study indicated that perovskite electrolyte BCZYZn is promising material for the next generation of intermediate temperature solid oxide fuel cells (IT-SOFCs).
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35. |
- Azad, A. K., et al.
(författare)
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Crystallographic and Magnetic Properties of the Spinel-type Ferrites ZnxCo1-xFe2O4 (0.0
- 2015
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Ingår i: AIP Conference Proceedings. - : AIP Publishing LLC. - 1551-7616 .- 0094-243X. - 9780735413047 ; 1660
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Konferensbidrag (refereegranskat)abstract
- Ultrahigh frequencies (UHF) have applications in signal and power electronics to minimize product sizes, increase production quantity and lower manufacturing cost. In the UHF range of 300 MHz to 3 GHz, ferrimagnetic iron oxides (ferrites) are especially useful because they combine the properties of a magnetic material with that of an electrical insulator. Ferrites have much higher electrical resistivity than metallic ferromagnetic materials, resulting in minimization of the eddy current losses, and total penetration of the electromagnetic (EM) field. Hence ferrites are frequently applied as circuit elements, magnetic storage media like read/write heads, phase shifters and Faraday rotators. The electromagnetic properties of ferrites are affected by operating conditions such as field strength, temperature and frequency. The spinel system ZnxCo1-xFe2O4 (x= 0.0, 0.25, 0.50 and 0.75) has been prepared by the standard solid state sintering method. X-ray and neutron powder diffraction measurements were performed at room temperature. Neutron diffraction data analysis confirms the cubic symmetry corresponding to the space group Fd3m. The distribution of three cations Zn2+, Co2+ and Fe3+ over the spinel lattice and other crystallographic parameters like lattice constant, oxygen position parameter, overall temperature factor and occupancies of different ions in different lattice sites for the samples have been determined from the analysis of neutron diffraction data. The lattice constant increases with increasing Zn content in the system. The magnetic structure was found to be ferrimagnetic for the samples with x
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36. |
- Azad, A.K., Eriksson, S.-G., Mellergård, A. Ivanov, S.A., Eriksen, J. Rundlöf, H.
(författare)
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A study on the nuclear and magnetic structure of the double perovskite A2FeWO6 (A = Sr, Ba) by neutron diffraction and reverse Monte Carlo modeling
- 2002
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Ingår i: Materials Research Bulletin. ; 37, s. 1797-1813
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Tidskriftsartikel (refereegranskat)
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37. |
- Azad, A.K., Mellergård, A., Eriksson, S.-G., Ivanov, S.A., Eriksen, J. and Rundlöf, H.
(författare)
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Preparation, crystal and magnetic structure of the double perovskite Ba2FeWo6
- 2002
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Ingår i: Applied Physics. ; A74, s. 763-765
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Tidskriftsartikel (refereegranskat)
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38. |
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39. |
- Ezekowitz, Michael D., et al.
(författare)
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Dabigatran with or without concomitant aspirin compared with warfarin alone in patients with nonvalvular atrial fibrillation (PETRO Study)
- 2007
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Ingår i: American Journal of Cardiology. - : Elsevier BV. - 0002-9149 .- 1879-1913. ; 100:9, s. 1419-1426
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Tidskriftsartikel (refereegranskat)abstract
- This is the first evaluation of dabigatran, an oral direct thrombin inhibitor, in patients with atrial fibrillation (AF). Patients (n = 502) were randomized to receive blinded doses of 50-, 150-, or 300-mg dabigatran twice daily alone or combined with 81- or 325-mg aspirin or open-label warfarin administered to achieve an international normalized ratio of 2 to 3 for 12 weeks. Dabigatran plasma concentrations, activated partial thromboplastin time, D-dimer, urinary 11-dehydrothromboxane B(2) (DTB2), and liver function were measured at baseline and at 1, 2, 4, 8, and 12 weeks. Clinical end points were assessed according to the treatment received at the time of the event. Overall, 92% of patients completed the study. Major hemorrhages were limited to the group treated with 300-mg dabigatran plus aspirin (4 of 64), and the incidence was significant versus 300-mg dabigatran alone (0 of 105, p <0.02). Total bleeding events were more frequent in the 300-mg (39 of 169, 23%) and 150-mg (30 of 169, 18%) dabigatran groups compared with the 50-mg groups (7 of 107, 7%; p = 0.0002 and p = 0.01, respectively). Thromboembolic events were limited to the 50-mg dabigatran dose groups (2 of 107, 2%). The mean trough d-dimer measurements were suppressed for the 2 highest doses of dabigatran and warfarin (international normalized ratio of 2 to 3). Aminotransferase levels >3 times the upper limit of normal were observed in 0.9% of the dabigatran recipients and in none of the warfarin recipients. Two dabigatran recipients had aminotransferase levels >5 times the upper limit of normal as a result of gallstones, which resolved. Trough activated partial thromboplastin time values were 1.2, 1.5, and 1.8 times the baseline level for the 50-, 150-, and 300-mg dabigatran groups, respectively. DTB2 concentrations after 12 weeks of 50-, 150-, and 300-mg dabigatran treatment were increased by 31%, 17%, and 23%, respectively, versus baseline (p = 0.02, p = 0.03, and p = 0.0004). In conclusion, major bleeding events were limited to patients treated with dabigatran 300 mg plus aspirin and thromboembolic episodes were limited to the 50-mg dabigatran groups. The 2 highest doses of dabigatran suppress D-dimer concentrations. Serious liver toxicity was not seen. The significance of the increase of DTB2 concentrations in dabigatran-treated patients needs resolution.
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40. |
- King, C, et al.
(författare)
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Community participatory learning and action cycle groups to reduce type 2 diabetes in Bangladesh (D:Clare): an updated study protocol for a parallel arm cluster randomised controlled trial
- 2023
-
Ingår i: Trials. - : Springer Science and Business Media LLC. - 1745-6215. ; 24:1, s. 218-
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Tidskriftsartikel (refereegranskat)abstract
- The “Diabetes: Community-led Awareness, Response and Evaluation” (D:Clare) trial aims to scale up and replicate an evidence-based participatory learning and action cycle intervention in Bangladesh, to inform policy on population-level T2DM prevention and control.The trial was originally designed as a stepped-wedge cluster randomised controlled trial, with the interventions running from March 2020 to September 2022. Twelve clusters were randomly allocated (1:1) to implement the intervention at months 1 or 12 in two steps, and evaluated through three cross-sectional surveys at months 1, 12 and 24. However, due to the COVID-19 pandemic, we suspended project activities on the 20th of March 2020. As a result of the changed risk landscape and the delays introduced by the COVID-19 pandemic, we changed from the stepped-wedge design to a wait-list parallel arm cluster RCT (cRCT) with baseline data. We had four key reasons for eventually agreeing to change designs: equipoise, temporal bias in exposure and outcomes, loss of power and time and funding considerations.Trial registrationISRCTN42219712. Registered on 31 October 2019.
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41. |
- Stock, SJ, et al.
(författare)
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The international Perinatal Outcomes in the Pandemic (iPOP) study: protocol
- 2021
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Ingår i: Wellcome open research. - : F1000 Research Ltd. - 2398-502X. ; 6, s. 21-
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Tidskriftsartikel (refereegranskat)abstract
- Preterm birth is the leading cause of infant death worldwide, but the causes of preterm birth are largely unknown. During the early COVID-19 lockdowns, dramatic reductions in preterm birth were reported; however, these trends may be offset by increases in stillbirth rates. It is important to study these trends globally as the pandemic continues, and to understand the underlying cause(s). Lockdowns have dramatically impacted maternal workload, access to healthcare, hygiene practices, and air pollution - all of which could impact perinatal outcomes and might affect pregnant women differently in different regions of the world. In the international Perinatal Outcomes in the Pandemic (iPOP) Study, we will seize the unique opportunity offered by the COVID-19 pandemic to answer urgent questions about perinatal health. In the first two study phases, we will use population-based aggregate data and standardized outcome definitions to: 1) Determine rates of preterm birth, low birth weight, and stillbirth and describe changes during lockdowns; and assess if these changes are consistent globally, or differ by region and income setting, 2) Determine if the magnitude of changes in adverse perinatal outcomes during lockdown are modified by regional differences in COVID-19 infection rates, lockdown stringency, adherence to lockdown measures, air quality, or other social and economic markers, obtained from publicly available datasets. We will undertake an interrupted time series analysis covering births from January 2015 through July 2020. The iPOP Study will involve at least 121 researchers in 37 countries, including obstetricians, neonatologists, epidemiologists, public health researchers, environmental scientists, and policymakers. We will leverage the most disruptive and widespread “natural experiment” of our lifetime to make rapid discoveries about preterm birth. Whether the COVID-19 pandemic is worsening or unexpectedly improving perinatal outcomes, our research will provide critical new information to shape prenatal care strategies throughout (and well beyond) the pandemic.
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42. |
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43. |
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44. |
- Zakaria, A. K. M., et al.
(författare)
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Synthesis, cation distribution and crystal structure of the spinel oxides MnGaxFe1-xCrO4 by neutron diffraction
- 2006
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Ingår i: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 385, s. 106-109
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Tidskriftsartikel (refereegranskat)abstract
- The spinel system MnGaxFe1-xCrO4 (x = 0-0, 0.25, 0.50, 0.75 and 1.0) was prepared by the solid state sintering method in air at 1523 K. X-ray and neutron powder diffraction measurements were performed on the samples at 295 K for structural characterization. Rietveld refinement of the neutron diffraction data revealed that all the samples of the series possessed cubic symmetry corresponding to the space group Fd3m. The distributions of the four cations Mn, Ga, Fe and Cr over the two sublattices and other crystallographic parameters were found. The lattice constant showed a decrease with increasing Ga content in the system. The magnetic structure at room temperature was found to be ferrimagnetic in the composition range x <= 0.50.
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45. |
- Abdalla, A. M., et al.
(författare)
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NdBaMn2O5+delta layered perovskite as an active cathode material for solid oxide fuel cells
- 2017
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Ingår i: Ceramics International. - : Elsevier BV. - 0272-8842. ; 43:17, s. 15932-15938
-
Tidskriftsartikel (refereegranskat)abstract
- A layered perovskite, NdBaMn2O5+delta (NBMO), was synthesized by solid state reaction method in air. Rietveld analysis of X-Ray Diffraction (XRD) data showed the material crystallizing in orthorhombic symmetry (Pmmm space group). Scanning electron microscopy (SEM) was used to check the morphology and, the analysis of the micrographs exhibited a porous structure with in-situ growth of nanoparticles. Electrochemical Impedance Spectroscopy (EIS) measurements from 600 degrees C to 800 degrees C shows the highest conductivity value of 1.17 x 10(-1) S/cm obtained at 800 degrees C with low activation energy (Ea) of 0.3 eV in air. In 5% H-2/Ar gas mixture, the conductivity and activation energy values were 1.97 x 10(-2) S/cm and 0.4 eV, respectively at 800 degrees C. The DC conductivity measurements also showed that this material is highly conductive in air with a conductivity value of 0.75 S/cm at 850 degrees C. Dual chamber fuel cell measurements on Ni-YSZ/YSZ/NBMO cell using 5% H-2/Ar as fuel (from 700 degrees C to 800 degrees C) showed a maximum power density of 0.202 W/cm(2) at 800 degrees C. The relatively high conductivity of the material in air and low activation energy makes it a potential candidate as cathode for solid oxide fuel cells.
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46. |
- Afif, A., et al.
(författare)
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Ceramic fuel cells using novel proton-conducting BaCe 0.5 Zr 0.3 Y 0.1 Yb 0.05 Zn 0.05 O 3-δ electrolyte
- 2022
-
Ingår i: Journal of Solid State Electrochemistry. - : Springer Science and Business Media LLC. - 1433-0768 .- 1432-8488. ; 1:26, s. 111-120
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Tidskriftsartikel (refereegranskat)abstract
- Protonic ceramic fuel cells have become extremely interesting due to their high power output at the intermediate temperature range (400–700 °C). Significant progress has been made to develop electrolyte materials, doped barium cerates-zirconate, which gets the leading role due to its high chemical stability and high ionic conductivity. Here, we present a new composition BaCe0.5Zr0.3Y0.1Yb0.05Zn0.05O3-δ (BCZYYbZn05), where addition of 5 mol% Zn with Ce, Zr, Y, and Yb at the B-site of the perovskite material shows high stability with high conductivity. The material was synthesized by solid-state reaction route at 1400 °C which showed 98% relative density. Rietveld analysis of neutron powder diffraction data reveal an orthorhombic structure with Pbnm space group. Thermogravimetric analysis shows about 1.06% weight loss from 200 to 1000 °C which is mainly related to the formation of the oxygen vacancies. In wet hydrogen atmosphere, this material shows higher conductivity and lower activation energy than dry hydrogen atmosphere indicates the conduction type as protonic conduction. The anode-supported single test cell based on this electrolyte material demonstrates peak power densities 649 mW cm−2 at 700 °C using conventional BSCF cathode, representing an important step toward commercially viable SOFC technology.
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47. |
- Afif, A., et al.
(författare)
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Electrochemical and structural characterization of BaCe 0.7 Zr 0.15 Y 0.1 Zn 0.05 O 3-δ as an electrolyte for SOFC-H
- 2018
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Ingår i: IET Conference Publications. ; 2018:CP750
-
Konferensbidrag (refereegranskat)abstract
- As a potential electrolyte for proton-conducting solid oxide fuel cells (SOFC-Hs) and to get better protonic conductivity and stability, zinc doped BCZY material has been found to be promising. In this study, we report a new composition of proton conductors BaCe0.7Zr0.15Y01Zn0.05O3-s (BCZYZn10) which was investigated using XRD, SEM and conductivity measurements. Rietveld refinement of the XRD data revel a cubic perovskite structure with Pm-3m space group. Rietveld analysis of BaCe07Zr0.15Y01Zn0.05O3-5 shows the unit cell parameter is a = 4.3582(7) A. Scanning electron microscopy images shows that the grain sizes are large and compact which gives the sample high density and good protonic conductivity. The total conductivity in wet atmosphere is significantly higher than that of dry condition and the conductivity was found to be 0.004032 Scm-1 and 0.00164 Scm-1 at 600 °C in wet and dry Ar, respectively. This study indicated that perovskite electrolyte BCZYZn10 is a promising material for the next generation intermediate temperature solid oxide fuel cells (IT-SOFCs).
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48. |
- Afif, A., et al.
(författare)
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Scheelite type Sr1−xBaxWO4 (x = 0.1, 0.2, 0.3) for possible application in Solid Oxide Fuel Cell electrolytes
- 2019
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 9:1
-
Tidskriftsartikel (refereegranskat)abstract
- © 2019, The Author(s). Polycrystalline scheelite type Sr1−xBaxWO4 (x = 0.1, 0.2 & 0.3) materials were synthesized by the solid state sintering method and studied with respect to phase stability and ionic conductivity under condition of technological relevance for SOFC applications. All compounds crystallized in the single phase of tetragonal scheelite structure with the space group of I41/a. Room temperature X-ray diffraction and subsequent Rietveld analysis confirms its symmetry, space group and structural parameters. SEM illustrates the highly dense compounds. Significant mass change was observed to prove the proton uptake at higher temperature by TG-DSC. All compound shows lower conductivity compared to the traditional BCZY perovskite structured materials. SBW with x = 0.3 exhibit the highest ionic conductivity among all compounds under wet argon condition which is 1.9 × 10−6 S cm−1 at 1000 °C. Since this scheelite type compounds show significant conductivity, the new series of SBW could serve in IT-SOFC as proton conducting electrolyte.
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49. |
- Asadian, S, et al.
(författare)
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Rhenium Perrhenate (188ReO4) Induced Apoptosis and Reduced Cancerous Phenotype in Liver Cancer Cells
- 2022
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Ingår i: Cells. - : MDPI AG. - 2073-4409. ; 11:2
-
Tidskriftsartikel (refereegranskat)abstract
- Recurrence in hepatocellular carcinoma (HCC) after conventional treatments is a crucial challenge. Despite the promising progress in advanced targeted therapies, HCC is the fourth leading cause of cancer death worldwide. Radionuclide therapy can potentially be a practical targeted approach to address this concern. Rhenium-188 (188Re) is a β-emitting radionuclide used in the clinic to induce apoptosis and inhibit cell proliferation. Although adherent cell cultures are efficient and reliable, appropriate cell-cell and cell-extracellular matrix (ECM) contact is still lacking. Thus, we herein aimed to assess 188Re as a potential therapeutic component for HCC in 2D and 3D models. The death rate in treated Huh7 and HepG2 lines was significantly higher than in untreated control groups using viability assay. After treatment with 188ReO4, Annexin/PI data indicated considerable apoptosis induction in HepG2 cells after 48 h but not Huh7 cells. Quantitative RT-PCR and western blotting data also showed increased apoptosis in response to 188ReO4 treatment. In Huh7 cells, exposure to an effective dose of 188ReO4 led to cell cycle arrest in the G2 phase. Moreover, colony formation assay confirmed post-exposure growth suppression in Huh7 and HepG2 cells. Then, the immunostaining displayed proliferation inhibition in the 188ReO4-treated cells on 3D scaffolds of liver ECM. The PI3-AKT signaling pathway was activated in 3D culture but not in 2D culture. In nude mice, Huh7 cells treated with an effective dose of 188ReO4 lost their tumor formation ability compared to the control group. These findings suggest that 188ReO4 can be a potential new therapeutic agent against HCC through induction of apoptosis and cell cycle arrest and inhibition of tumor formation. This approach can be effectively combined with antibodies and peptides for more selective and personalized therapy.
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50. |
- Azad, A.K., Eriksson, S.-G., Ivanov, S.A., Rundlöf, H., Eriksen, J. Mathieu, R., Svedlindh, P.
(författare)
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Structural and magnetic characterization of the double perovskites AA´MnWO6 (AA´= Ba2, SrBa, Sr2, SrCa and Ca2)
- 2002
-
Ingår i: Ferroelectrics. ; 269, s. 105-110
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Tidskriftsartikel (refereegranskat)
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