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61.
Wenbo Zhou Julia Craft Alex Ojemann Luke Bergen Arin Graner Aitana Gonzales Qianbin He Timothy Kopper Marie Smith Michael W. Graner Xiaoli Yu 《International journal of molecular sciences》2022,23(13)
WHO Grade 4 IDH-wild type astrocytoma (GBM) is the deadliest brain tumor with a poor prognosis. Meningioma (MMA) is a more common “benign” central nervous system tumor but with significant recurrence rates. There is an urgent need for brain tumor biomarkers for early diagnosis and effective treatment options. Extracellular vesicles (EVs) are tiny membrane-enclosed vesicles that play essential functions in cell-to-cell communications among tumor cells. We aimed to identify epitopes of brain tumor EVs by phage peptide libraries. EVs from GBM plasma, MMA plasma, or brain tumor cell lines were used to screen phage-displayed random peptide libraries to identify high-affinity peptides. We purified EVs from three GBM plasma pools (23 patients), one MMA pool (10 patients), and four brain tumor cell lines. We identified a total of 21 high-affinity phage peptides (12 unique) specific to brain tumor EVs. The peptides shared high sequence homologies among those selected by the same EVs. Dose–response ELISA demonstrated that phage peptides were specific to brain tumor EVs compared to controls. Peptide affinity purification identified unique brain tumor EV subpopulations. Significantly, GBM EV peptides inhibit brain tumor EV-induced complement-dependent cytotoxicity (necrosis) in neurons. We conclude that phage display technology could identify specific peptides to isolate and characterize tumor EVs. 相似文献
62.
Michael J. Hill Udaya Senarath Alex Lee Melanie Zeppel Joanne M. Nightingale Tim R. McVicar 《Remote sensing of environment》2006,101(4):495-518
The leaf area index (LAI) product from the Moderate Resolution Imaging Spectroradiometer (MODIS) is important for monitoring and modelling global change and terrestrial dynamics at many scales. The algorithm relies on spectral reflectances and a six biome land cover classification. Evaluation of the specific behaviour and performance of the product for regions of the globe such as Australia are needed to assist with product refinement and validation. We made an assessment of Collection 4 of the MODIS LAI product using four approaches: (a) assessment against a continental scale Structural Classification of Australian Vegetation (SCAV); (b) assessment against a continental scale land use classification (LUC); (c) assessment against historical field-based measurement of LAI collected prior to the Terra Mission; and (d) direct comparison of MODIS LAI with coincident field measurements of LAI, mostly from hemispherical photography. The MODIS LAI product produced a wide variety of geographically and structurally specific temporal response profiles between different classes and even for sub-groups within classes of the SCAV. Historical and concurrent field measurements indicated that MODIS LAI was giving reasonable estimates for LAI for most cover types and land use types, but that major overestimation of LAI occurs in some eastern Australian open forests and woodlands. The six biome structural land cover classification showed some significant deviations in class allocation compared to the SCAV particularly where grasslands are allocated to shrubland, savanna woodlands are allocated to shrubland, savanna and broadleaf forest, and open forests are allocated to savanna and broadleaf forest. The land cover and LAI products could benefit from some additional examination of Australian data addressing the structural representation of Eucalypt canopies in the “space of canopy realisation” for savanna and broadleaf forest classes. 相似文献
63.
Alex A. Meier Eden P. Go Hee-Jung Moon Heather Desaire Minae Mure 《International journal of molecular sciences》2022,23(11)
Lysyl oxidase-like 2 (LOXL2) catalyzes the oxidative deamination of peptidyl lysines and hydroxylysines to promote extracellular matrix remodeling. Aberrant activity of LOXL2 has been associated with organ fibrosis and tumor metastasis. The lysine tyrosylquinone (LTQ) cofactor is derived from Lys653 and Tyr689 in the amine oxidase domain via post-translational modification. Based on the similarity in hydrodynamic radius and radius of gyration, we recently proposed that the overall structures of the mature LOXL2 (containing LTQ) and the precursor LOXL2 (no LTQ) are very similar. In this study, we conducted a mass spectrometry-based disulfide mapping analysis of recombinant LOXL2 in three forms: a full-length LOXL2 (fl-LOXL2) containing a nearly stoichiometric amount of LTQ, Δ1-2SRCR-LOXL2 (SRCR1 and SRCR2 are truncated) in the precursor form, and Δ1-3SRCR-LOXL2 (SRCR1, SRCR2, SRCR3 are truncated) in a mixture of the precursor and the mature forms. We detected a set of five disulfide bonds that is conserved in both the precursor and the mature recombinant LOXL2s. In addition, we detected a set of four alternative disulfide bonds in low abundance that is not associated with the mature LOXL2. These results suggest that the major set of five disulfide bonds is retained post-LTQ formation. 相似文献
64.
Hydropeaking dam operation and water extractions for irrigation have been broadly stated as alterations to natural flow regimes, which have also been noticed in the Biobío Watershed, in Central Chile, since 1996. In the Biobío River, most of native fish species are endemic and very little is known about them. Their ecological and social values have never been estimated, and there is lack of information about their habitat preferences. Furthermore, changes on fish habitat availability due to natural and/or man‐made causes have not been evaluated. In this study, eight native fish species, in a representative reach of the Biobío River, were studied and their preferred habitats were surveyed and characterized. A hydrodynamic model was built and linked to the fish habitat simulation model CASiMiR. Fuzzy rules and fuzzy sets were developed for describing habitat preference of the native fish species. CASiMiR was then used to simulate how physical habitat conditions vary due to flow control (i.e. upstream dams). Results show how overall habitat quality, expressed as weighted usable area (WUA) and hydraulic habitat suitability (HHS), changes and fluctuates due to the dam operation and how the daily hydropeaking is influencing quantity, quality and location of different habitats. The study suggests that the analysed fish are highly susceptible to flow control, as dams are currently operated, and fish habitat improvement suggestions are proposed. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
65.
The magic of computer graphics as seen in many current movies and computer games comes at a cost. Creating the geometric forms with which to generate synthetic characters and animating the characters to bring them to life require either highly skilled artists and/or sophisticated capture devices. Both are expensive and, in the case of highly skilled artists, rare. 相似文献
66.
Alex M. Ruderman Seung-Kyum Choi Roger J. Jiao 《Journal of Intelligent Manufacturing》2013,24(3):641-652
Design chain management requires many decision makers throughout the product development process. It is critical to reduce complexity and uncertainty of the design process by correctly modeling subjective data associated with decision makers’ preferences. This paper aims at using decision support to find optimal designs by modeling respondent preferences and trade-offs with consideration of uncertainty. Specifically, a simulation-based ranking methodology is implemented and incorporated with traditional conjoint analysis. This process facilitates a schematic decision support process by alleviating user fatigue. In addition, incorporation of uncertainty in the ranking process provides the capability of producing robust and reliable products. The efficacy and applicability of simulation-based conjoint ranking is demonstrated with a case study of a power-generating shock absorber design. 相似文献
67.
This article describes some of the challenges of supporting older adults’ creative input to the design of an (as yet) undefined digital television application. Focusing on commonly used brainstorming and paper prototyping techniques, constructive insights are gathered from users with limited experience of interactive technology. Encouraging older participants to move beyond what they are familiar with, the research reports on how fragmented conceptual knowledge of familiar technologies can either facilitate or impede the creative development of new ideas. This includes bias or contradictory ideas that can emerge in the elicitation process. As reported, other factors, such as the self-perception of inadequate drawing skills, demonstrate further barriers for some older adults to articulate their visions and aspirations for suitably designed technology. 相似文献
68.
We argue that more help does not necessarily lead to more gratitude. Rather, gratitude depends on how a given instance of help compares with the help that a person is used to receiving. Participants read vignettes detailing an event in which 11 different friends either lent them varying amounts of money or spent varying amounts of time providing help. The amount of gratitude elicited by a given amount of help (e.g., a loan of £36 [about $56] or 49 min help) differed substantially depending on how this amount ranked among the help they were getting from their other friends. Comparison across four experimental conditions suggested that these judgments operated via the same general cognitive mechanisms used to judge other social events and psychophysical stimuli (as outlined by range frequency theory). Although more help does lead to more gratitude, people appear to be sensitive to how that help compares with what others are providing, and experienced gratitude depends on these relative judgments. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
69.
Research productivity affects the careers of academic psychologists. Unfortunately, there is a surprising lack of consensus on productivity’s meaning, measurement, and how to compare the productivity of one academic psychologist to another. In the present study, we review academic productivity research within psychology, and using a sample of 673 psychologists, compute six indexes of productivity. Most productivity metrics (publication count, citation count, or some combination of the two) were substantially interrelated and one (Integrated Research Productivity Index) was independent from years in the field. Female psychologists were equally as productive as male psychologists after accounting for years in the field, and pre-tenure psychologists showed steeper change-over-time productivity slopes than post-tenure psychologists. Based on these findings, we provide recommendations for the use and measurement of academic research productivity. 相似文献
70.
Kangmin Wu Patigul Imin Alex Adronov Igor Zhitomirsky 《Materials Chemistry and Physics》2011,125(1-2):210-218
Poly[3-(3-N,N-diethylaminopropoxy)thiophene] (PDAOT) was prepared by oxidative polymerization and investigated by ultraviolet (UV), Raman and nuclear magnetic resonance (NMR) spectroscopies. Protonated PDAOT was dissolved in water or ethanol/water mixtures and deposited by cathodic electrophoretic deposition (EPD) on conductive substrates. Film thickness was varied in the range of 0–5 μm by controlling the deposition voltage and deposition time. PDAOT was found to form strong supramolecular interactions with single-walled carbon nanotubes (SWNTs), allowing the formation of stable and concentrated nanotube dispersions, which were used for the formation of composite PDAOT–SWNT films by EPD. Furthermore, introduction of ZnO particles to the PDAOT solutions also allowed the formation of PDAOT–ZnO composite films by EPD. The composition of the films was varied by changing the concentration of SWNTs and ZnO in the suspensions. The dispersion of ZnO particles was improved using protonated dopamine (DA) as a dispersant. The deposits were studied by X-ray analysis (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA), X-ray diffraction and scanning electron microscopy (SEM). 相似文献