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| 2. |
- Lowry, Stephanie, 1979-, et al.
(författare)
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Lightweight, Viewpoint-Invariant Visual Place Recognition in Changing Environments
- 2018
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Ingår i: IEEE Robotics and Automation Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 2377-3766. ; 3:2, s. 957-964
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a viewpoint-invariant place recognition algorithm which is robust to changing environments while requiring only a small memory footprint. It demonstrates that condition-invariant local features can be combined with Vectors of Locally Aggregated Descriptors (VLAD) to reduce high-dimensional representations of images to compact binary signatures while retaining place matching capability across visually dissimilar conditions. This system provides a speed-up of two orders of magnitude over direct feature matching, and outperforms a bag-of-visual-words approach with near-identical computation speed and memory footprint. The experimental results show that single-image place matching from non-aligned images can be achieved in visually changing environments with as few as 256 bits (32 bytes) per image.
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| 3. |
- Fulda, S., et al.
(författare)
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Betulinic acid triggers CD95 (APO-1/Fas)- and p53-independent apoptosis via activation of caspases in neuroectodermal tumors
- 1997
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Ingår i: Cancer Research. - : American Association for Cancer Research. - 0008-5472 .- 1538-7445. ; 57:21, s. 4956-4964
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Tidskriftsartikel (refereegranskat)abstract
- Betulinic acid CBA), a melanoma-specific cytotoxic agent, induced apoptosis in neuroectodermal tumors, such as neuroblastoma, medulloblastoma, and Ewing's sarcoma, representing the most common solid tumors of childhood. BA triggered an apoptosis pathway different from the one previously identified for standard chemotherapeutic drugs. BA-induced apoptosis was independent of CD95-ligand/receptor interaction and accumulation of wild-type p53 protein, but it critically depended on activation of caspases (interleukin 1 beta-converting enzyme/Ced-3-like proteases), FLICE/MACH (caspase-8), considered to be an upstream protease in the caspase cascade, and the downstream caspase CPP32/YAMA/Apopain (caspase-3) were activated, resulting in cleavage of the prototype substrate of caspases PARP. The broad-spectrum peptide inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone, which blocked cleavage of FLICE and PARP, also completely abrogated BA-triggered apoptosis. Cleavage of caspases was preceded by disturbance of mitochondrial membrane potential and by generation of reactive oxygen species. Overexpression of Bcl-2 and Bcl-x(L) conferred resistance to BA at the level of mitochondrial dysfunction, protease activation, and nuclear fragmentation. This suggested that mitochondrial alterations were involved in BA-induced activation of caspases. Furthermore, pax and Bcl-x(s), two death-promoting proteins of the Bcl-2 family, were up-regulated following BA treatment. Most importantly, neuroblastoma cells resistant to CD95- and doxorubicin-mediated apoptosis were sensitive to treatment with BA, suggesting that BA may bypass some forms of drug resistance. Because BA exhibited significant antitumor activity on patients' derived neuroblastoma cells ex vivo, BA may be a promising new agent for the treatment of neuroectodermal tumors in vivo.
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| 4. |
- Grishenkov, Dmitry, 1983-, et al.
(författare)
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Characterization of acoustic properties of PVA-shelled ultrasound contrast agents : linear properties (Part I)
- 2009
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Ingår i: Ultrasound in Medicine and Biology. - : Elsevier BV. - 0301-5629 .- 1879-291X. ; 35:7, s. 1127-1138
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Tidskriftsartikel (refereegranskat)abstract
- This work examines the linear acoustic behavior of ultrasound contrast agents made of three types of poly (vinyl alcohol) (PVA) shelled microbubbles manufactured at different pH and temperature conditions. Back-scattered power, attenuation coefficient and phase velocity of ultrasonic waves propagating through suspensions of PVA contrast agents were measured at temperature values ranging between 24 degrees C and 37 degrees C in a frequency range from 3 MHz to 13 MHz. Enhancement of the backscattered power higher than 20 dB and displaying a weak dependence on temperature was observed. Attenuation and phase velocity, on the other hand, showed higher sensitivity to temperature variations. A modified version of the Church model, which accounts for the dispersion of the dynamic modulus of the PVA shells, was developed to simultaneously fit the attenuation and phase velocity data at 24 degrees C. The frequency dependence of the storage modulus was found to be that of semiflexible polymeric networks. On the other hand, the frequency dependence of the dynamic loss modulus suggests that additional mechanisms, which may be related to the finite dimensions of the shell and/or to its inhomogeneity, may play a significant role in the dissipation of the acoustic energy. For the microbubbles of interest, this model predicts frequency dependent resonance frequency higher than 100 MHz.
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| 5. |
- Muroyama, Norihiro, et al.
(författare)
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Argon adsorption on MCM-41 mesoporous crystal studied by in situ synchrotron powder X-ray diffraction
- 2008
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Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 112:29, s. 10803-10813
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Tidskriftsartikel (refereegranskat)abstract
- Equilibrium argon adsorption from the gas phase on mesoporous MCM-41 silica of hexagonal structure is directly studied by in situ synchrotron powder X-ray diffraction (XRD) measurements at SPring-8. The diffraction intensity data is analyzed by extending the previously developed analytical formula for the crystal structure factors of MCM-41 to account for argon adsorbed in the pores. It is clearly observed that argon adsorbs in layers on the pore walls at low gas pressures and exhibits sudden capillary condensation as the gas pressure increased. The proposed method of interpretation of XRD data allows one to calculate the density ratio between the silica wall and condensed argon, the pore size, and the pore wall fluctuation/roughness, together with the thickness of the adsorbed layer as a function of the gas pressure. The results of in situ XRD experiments are compared with the results of argon adsorption volumetric experiments. The adsorption data are interpreted with the quench solid density functional theory (QSDFT), which takes into account the pore wall roughness. The perfect agreement of the QSDFT isotherm predicted from the adsorption data and the XRD recalculated isotherm suggests that the adsorption porosimetry and XRD measurements can be reconciled provided a proper interpretation of the experimental data.
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| 6. |
- Moilanen, Johanna, et al.
(författare)
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Being, becoming and belonging in constructing children’s lived citizenship with contact persons and contact families
- 2023
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Ingår i: Barn. - Trondheim : Norsk senter for barneforskning. - 0800-1669 .- 2535-5449. ; 41:2–3, s. 74-89
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Tidskriftsartikel (refereegranskat)abstract
- The article discusses children’s citizenship by linking the dimensions of being, becoming and belonging to the concept of lived citizenship in the context of contact person and contact family interventions. Drawing on empirical research from Finland and Sweden, the article elaborates on how to identify if, and if so, how, children’s lived citizenship is constructed in contact person and contact family interventions and to what extent these constructions leave room for children’s perspectives. The results of the study indicate that contact person and contact family interventions contribute to the construction of children’s citizenship in various ways that include the perspectives on children and childhood of being, becoming and belonging. However, children’s active participation often seems to be governed by adults. Thus, giving greater attention to children’s intergenerational connections, i.e., adults’ roles in forming children’s citizenship, is needed.
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| 8. |
- Moiloa, Ntwai A., et al.
(författare)
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Chapter 19 Systematics and evolution
- 2022
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Ingår i: In: de Boer H, Rydmark MO, Verstraete B, Gravendeel B (2022) Molecular identification of plants: from sequence to species. Advanced Books.. - : Pensoft Publishers.
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Bokkapitel (refereegranskat)
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