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991.
Ming Tian Taylor Ticer Qikun Wang Sierra Walker Anthony Pham Annie Suh Sara Busatto Irina Davidovich Rawan Al‐Kharboosh Laura Lewis‐Tuffin Baoan Ji Alfredo Quinones‐Hinojosa Yeshayahu Talmon Shane Shapiro Felix Rückert Joy Wolfram 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(10)
Extracellular vesicles secreted from adipose‐derived mesenchymal stem cells (ADSCs) have therapeutic effects in inflammatory diseases. However, production of extracellular vesicles (EVs) from ADSCs is costly, inefficient, and time consuming. The anti‐inflammatory properties of adipose tissue‐derived EVs and other biogenic nanoparticles have not been explored. In this study, biogenic nanoparticles are obtained directly from lipoaspirate, an easily accessible and abundant source of biological material. Compared to ADSC‐EVs, lipoaspirate nanoparticles (Lipo‐NPs) take less time to process (hours compared to months) and cost less to produce (clinical‐grade cell culture facilities are not required). The physicochemical characteristics and anti‐inflammatory properties of Lipo‐NPs are evaluated and compared to those of patient‐matched ADSC‐EVs. Moreover, guanabenz loading in Lipo‐NPs is evaluated for enhanced anti‐inflammatory effects. Apolipoprotein E and glycerolipids are enriched in Lipo‐NPs compared to ADSC‐EVs. Additionally, the uptake of Lipo‐NPs in hepatocytes and macrophages is higher. Lipo‐NPs and ADSC‐EVs have comparable protective and anti‐inflammatory effects. Specifically, Lipo‐NPs reduce toll‐like receptor 4‐induced secretion of inflammatory cytokines in macrophages. Guanabenz‐loaded Lipo‐NPs further suppress inflammatory pathways, suggesting that this combination therapy can have promising applications for inflammatory diseases. 相似文献
992.
Nanoparticle‐Enhanced Silver‐Nanowire Plasmonic Electrodes for High‐Performance Organic Optoelectronic Devices 下载免费PDF全文
Taehyo Kim Saewon Kang Jungwoo Heo Seungse Cho Jae Won Kim Ayoung Choe Bright Walker Ravi Shanker Hyunhyub Ko Jin Young Kim 《Advanced materials (Deerfield Beach, Fla.)》2018,30(28)
Improved performance in plasmonic organic solar cells (OSCs) and organic light‐emitting diodes (OLEDs) via strong plasmon‐coupling effects generated by aligned silver nanowire (AgNW) transparent electrodes decorated with core–shell silver–silica nanoparticles (Ag@SiO2NPs) is demonstrated. NP‐enhanced plasmonic AgNW (Ag@SiO2NP–AgNW) electrodes enable substantially enhanced radiative emission and light absorption efficiency due to strong hybridized plasmon coupling between localized surface plasmons (LSPs) and propagating surface plasmon polaritons (SPPs) modes, which leads to improved device performance in organic optoelectronic devices (OODs). The discrete dipole approximation (DDA) calculation of the electric field verifies a strongly enhanced plasmon‐coupling effect caused by decorating core–shell Ag@SiO2NPs onto the AgNWs. Notably, an electroluminescence efficiency of 25.33 cd A?1 (at 3.2 V) and a power efficiency of 25.14 lm W?1 (3.0 V) in OLEDs, as well as a power conversion efficiency (PCE) value of 9.19% in OSCs are achieved using hybrid Ag@SiO2NP–AgNW films. These are the highest values reported to date for optoelectronic devices based on AgNW electrodes. This work provides a new design platform to fabricate high‐performance OODs, which can be further explored in various plasmonic and optoelectronic devices. 相似文献
993.
Lauren M. Garten Shyam Dwaraknath Julian Walker John S. Mangum Paul F. Ndione Yoonsang Park Daniel A. Beaton Venkatraman Gopalan Brian P. Gorman Laura T. Schelhas Michael F. Toney Susan Trolier‐McKinstry Kristin A. Persson David S. Ginley 《Advanced materials (Deerfield Beach, Fla.)》2018,30(25)
Many technologically critical materials are metastable under ambient conditions, yet the understanding of how to rationally design and guide the synthesis of these materials is limited. This work presents an integrated approach that targets a metastable lead‐free piezoelectric polymorph of SrHfO3. First‐principles calculations predict that the previous experimentally unrealized, metastable P4mm phase of SrHfO3 should exhibit a direct piezoelectric response (d33) of 36.9 pC N?1 (compared to d33 = 0 for the ground state). Combining computationally optimized substrate selection and synthesis conditions lead to the epitaxial stabilization of the polar P4mm phase of SrHfO3 on SrTiO3. The films are structurally consistent with the theory predictions. A ferroelectric‐induced large signal effective converse piezoelectric response of 5.2 pm V?1 for a 35 nm film is observed, indicating the ability to predict and target multifunctionality. This illustrates a coupled theory‐experimental approach to the discovery and realization of new multifunctional polymorphs. 相似文献
994.
Jonathan J. P. Peters Ana M. Sanchez David Walker Roger Whatmore Richard Beanland 《Advanced materials (Deerfield Beach, Fla.)》2019,31(5)
Highly B‐site ordered Pb2ScTaO6 crystals are studied as a function of temperature via dielectric spectroscopy and in situ high‐dynamic‐range electron diffraction. The degree of ordering is examined on the local and macroscopic scale and is determined to be 76%. Novel analysis of the electron diffraction patterns provides structural information with two types of antiferroelectric displacements determined to be present in the polar structure. It is then found that a low‐temperature transition occurs on cooling at ≈210 K that is not present on heating. This phenomenon is discussed in terms of the freezing of dynamic polar nanodomains where a high density of domain walls creates a metastable state. 相似文献
995.
BACKGROUND: We studied the relations between physical activity and changes in physical activity, all-cause mortality, and incidence of major coronary-heart-disease events in older men. METHODS: In 1978-80 (Q1), 7735 men aged 40-59 were selected from general practices in 24 British towns, and enrolled in a prospective study of cardiovascular disease, which included physical activity data. In 1992 (Q92), 12-14 years later, 5934 of the men (91% of available survivors, mean age 63 years) gave further information on physical activity and were then followed up for a further 4 years. The main endpoints were all-cause mortality during 4 years of follow-up from Q92, and major fatal and non-fatal coronary-heart-disease events during 3 years of follow-up from Q92. FINDINGS: Among 4311 men with no history of coronary heart disease, stroke, or "other heart trouble" by Q92 and who did not report "poor health", there were 219 deaths. In the inactive/occasionally active, light, moderate, and moderately vigorous/vigorous activity groups there were 101 (18.5/1000 person-years) 48 (11.4), 23 (7.3), and 47 (9.1) deaths, respectively (adjusted risk ratios 1.00, 0.61 [95% CI 0.48-0.86], 0.50 [0.31-0.79], 0.65 [0.45-0.94]). Men who were sedentary at Q1 and who began at least light activity by Q92 had significantly lower all-cause mortality than those who remained sedentary, even after adjustment for potential confounders (risk ratio=0.55 [0.36-0.84]). Physical activity improved both cardiovascular mortality (0.66 [0.35-1.23]) and non-cardiovascular mortality (0.48 [0.27-0.85]). The relation between physical activity at Q92, changes in physical activity, and mortality were similar for men with pre-existing cardiovascular disease. INTERPRETATION: Maintaining or taking up light or moderate physical activity reduces mortality and heart attacks in older men with and without diagnosed cardiovascular disease. Our results support public-health recommendations for older sedentary people to increase physical activity, and for active middle-aged people to continue their activity into old age. 相似文献
996.
OBJECTIVES: Despite the recent introduction of new peroral drugs as well as neurosurgical methods for Parkinson's disease, treatment of late stage parkinsonian patients remains difficult and many patients become severely handicapped because of fluctuations in their motor status. Injections and infusions of apomorphine has been suggested as an alternative in the treatment of these patients, but the number of studies describing the effects of such a treatment over longer time periods is still limited. The objective was to investigate the therapeutic response and range of side effects during long term treatment with apomorphine in advanced Parkinson's disease. METHODS: Forty nine patients (30 men, 19 women; age range 42-80 years) with Parkinson's disease were treated for 3 to 66 months with intermittent subcutaneous injections or continuous infusions of apomorphine. RESULTS: Most of the patients experienced a long term symptomatic improvement. The time spent in "off" was significantly reduced from 50 to 29.5% with injections and from 50 to 25% with infusions of apomorphine. The quality of the remaining "off" periods was improved with infusion treatment, but was relatively unaffected by apomorphine injections. The overall frequency and intensity of dyskinesias did not change. The therapeutic effects of apomorphine were stable over time. The most common side effect was local inflammation at the subcutaneous infusion site, whereas the most severe were psychiatric side effects occurring in 44% of the infusion and 12% of the injection treated patients. CONCLUSION: Subcutaneous apomorphine is a highly effective treatment which can substantially improve the symptomatology in patients with advanced stage Parkinson's disease over a prolonged period of time. 相似文献
997.
We have measured the linearity, spatial resolution (MTF), noise (NPS), and signal-to-noise characteristics (DQE) of an electronic portal imaging device (EPID) based on an amorphous silicon flat-panel array. The array has a 128 x 128-pixel matrix and each pixel is 0.75 x 0.75 mm2 in dimension so the array covers an area of 96 x 96 mm2. The array acts like a large area light sensor and records the optical signals generated in a metal plate/phosphor screen x-ray detector when the detector is irradiated by a megavoltage x-ray beam. In addition, approximately 0.5% of the total signal is generated by nonoptical processes. The noise measurements show that the device is quantum noise limited with the noise power generated by the x-ray quanta being up to 100 times greater than the noise added by the external readout electronics and flat-panel light sensor itself. However, the flat-panel light sensor does reduce the spatial resolution (compared to a perfect optical sensor with infinitesimal pixel size) because of its moderate pixel size and because optical spread can occur in the transparent glues used to attach the phosphor screen to the flat-panel light sensor. The response of the sensor is very linear and does not suffer from the glare phenomenon associated with TV camera-based EPIDs--characteristics which suggest that the amorphous silicon EPID will be well suited to transit dosimetry. Nevertheless, some limitations need to be overcome before these devices can be used clinically. These include developing larger flat-panel light sensors, the elimination of "noisy" pixels with high dark signal, and improvements in the uniform sensitivity of the sensors. This last requirement is only needed for transit dosimetry applications where it would greatly simplify calibration of the device. In addition, an image acquisition scheme must be developed to eliminate artifacts created by the pulsed x-ray beam generated by linear accelerators. Despite these limitations, our studies suggest that the amorphous silicon EPIDs are very well suited to portal imaging. 相似文献
998.
Johnny Guzman Alexandre Madureira Marcus Sarkis Shawn Walker 《Journal of scientific computing》2018,77(3):1736-1761
We derive error estimates for the piecewise linear finite element approximation of the Laplace–Beltrami operator on a bounded, orientable, \(C^3\), surface without boundary on general shape regular meshes. As an application, we consider a problem where the domain is split into two regions: one which has relatively high curvature and one that has low curvature. Using a graded mesh we prove error estimates that do not depend on the curvature on the high curvature region. Numerical experiments are provided. 相似文献
999.
AbstractA paradigm is an accepted world view. If we do not continually question our paradigm then wider trends and movements will overtake the discipline leaving it ill adapted to future challenges. This Special Issue is an opportunity to keep systems thinking at the forefront of ergonomics theory and practice. Systems thinking prompts us to ask whether ergonomics, as a discipline, has been too timid? Too preoccupied with the resolution of immediate problems with industrial-age methods when, approaching fast, are developments which could render these operating assumptions an irrelevance. Practical case studies are presented to show how abstract systems problems can be tackled head-on to deliver highly innovative and cost-effective insights. The strategic direction of the discipline foregrounds high-quality systems problems. These are something the discipline is well able to respond to provided that the appropriate operating paradigms are selected.Practitioner Summary: High-quality systems problems are the future of the discipline. How do we convert obtuse sounding systems concepts into practical interventions? In this paper, the essence of systems thinking is distilled and practical case studies used to demonstrate the benefits of this new paradigm. 相似文献
1000.
Novel 2,2′,6,6′-tetrabromo-3,3′,5,5′-tetramethyl-4,4′-biphenol (TBTMBP), and its epoxy derivatives, were synthesized to incorporate the stable meta-brominated phenol moiety into epoxy resin systems. In electronic encapsulation and laminate applications, epoxy systems derived from TBTMBP have exhibited superior hydrolytic and thermal stability as compared with the conventional ortho-brominated epoxy resins. These properties have resulted in an extended device life for semiconductors and a high Tg with excellent blister resistance for the printed circuit board, while meeting flame retardancy requirements as well. 相似文献