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241.
Seulah Lee Man Hyung Koo Dong-Won Han Il-Chan Kim Jun Hyuck Lee Jeong-Hoon Kim Razia Sultana Sun Yeou Kim Ui Joung Youn Jin-Hyoung Kim 《Molecules (Basel, Switzerland)》2022,27(14)
Total fatty-acid (FA) contents of different organs (stomach, liver, brain, and skin) of two Antarctic fish, marbled rockcod (Notothenia rossii) and mackerel icefish (Champsocephalus gunnari), were examined using gas chromatography–mass spectrometry (GC–MS). N. rossii possessed higher contents of total omega-3, where eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the most represented omega-3 FAs, were distributed throughout all parts of the fish. The highest level of EPA was observed in the skin and that of DHA was observed in the brain of N. rossii. C. gunnari showed organ peculiarity in that most of the omega-3 FAs were found in stomach and skin. Specifically, the highest levels of EPA and DHA were both observed in the stomach. Although N. rossii and C. gunnari both inhabit the Antarctic Southern Oceans, their characteristics in terms of the composition of fatty acids were shown to vary. The extracts were also evaluated for matrix metalloproteinase-1 (MMP-1)-inhibitory activities in UVB-induced human dermal fibroblasts, where extracts of the skin and liver of N. rossii showed the most significant inhibition upon MMP-1 production. These findings provide experimental evidence that the extracts of the Antarctic fish could be utilized as bioactive nutrients, particularly in the enhancement of skin health. 相似文献
242.
Joseph Lau Hwan Lee Julie Rousseau Franois Bnard Kuo-Shyan Lin 《Molecules (Basel, Switzerland)》2022,27(15)
Radioligand therapy (RLT) is an emergent drug class for cancer treatment. The dose administered to cancer patients is constrained by the radiation exposure to normal tissues to maintain an appropriate therapeutic index. When a radiopharmaceutical or its radiometabolite is retained in the kidneys, radiation dose deposition in the kidneys can become a dose-limiting factor. A good exemplar is [177Lu]Lu-DOTATATE, where patients receive a co-infusion of basic amino acids for nephroprotection. Besides peptides, there are other classes of targeting vectors like antibody fragments, antibody mimetics, peptidomimetics, and small molecules that clear through the renal pathway. In this review, we will review established and emerging strategies that can be used to mitigate radiation-induced nephrotoxicity, with a focus on the development and incorporation of cleavable linkers for radiopharmaceutical designs. Finally, we offer our perspectives on cleavable linkers for RLT, highlighting future areas of research that will help advance the technology. 相似文献
243.
244.
Katagiri S. Biing-Hwang Juang Chin-Hui Lee 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1998,86(11):2345-2373
This paper provides a comprehensive introduction to a novel approach to pattern recognition which is based on the generalized probabilistic descent method (GPD) and its related design algorithms. The paper contains a survey of recent recognizer design techniques, the formulation of GPD, the concept of minimum classification error learning that is closely related to the GPD formalization, a relational analysis between GPD and other important design methods, and various embodiments of GPD-based design, including segmental-GPD, minimum spotting error training, discriminative utterance verification, and discriminative feature extraction. GPD development has its origins in basic pattern recognition and Bayes decision theory. It represents a simple but careful re-investigation of the classical theory and successfully leads to an innovative framework. For clarity of presentation, detailed discussions about its embodiments are provided for examples of speech pattern recognition tasks that use a distance-based classifier. Experimental results in speech pattern recognition tasks clearly demonstrate the remarkable utility of the family of GPD-based design algorithms 相似文献
245.
Jung-Ja Yang Rafal Spirydon Tae-Yeon Seong S. H. Lee G. B. Stringfellow 《Journal of Electronic Materials》1998,27(10):1117-1123
Transmission electron diffraction (TED) and transmission electron microscope (TEM) studies have been made of organometallic
vapor phase epitaxial GaxIn1−xP layers (x ≈ 0.5) grown at temperatures in the range 570–690°C to investigate ordering and ordered domain structures. TED
and TEM examination shows that the size and morphology of ordered domains depend on the growth temperature. The ordered domains
change from a fine rod-like shape to a plate-like shape as the growth temperature increases. The domains are of width 0.6∼2
nm and of length 1∼10 nm. Characteristic diffuse features observed in TED patterns are found to depend on the growth temperature.
Extensive computer simulations show a direct correlation between the ordered domain structures and such diffuse features.
A possible model is suggested to describe the temperature dependence of the ordered domain structure. 相似文献
246.
Do Il Chang Dong Sung Lim Min Yong Jeon Hak Kyu Lee Kyong Hon Kim Taesang Park 《Electronics letters》2000,36(16):1356-1358
Dual-wavelength lasing at 1480 and 1500 nm has been demonstrated from a cascaded Raman fibre laser with a WDM coupler and two pairs of Bragg gratings. Intensity-adjustable, wavelength-tunable laser operation was achieved by tensile stress wavelength tuning of the gratings 相似文献
247.
Y.C. ChangM.L. Huang Y.H. ChangY.J. Lee H.C. ChiuJ. Kwo M. Hong 《Microelectronic Engineering》2011,88(7):1207-1210
Al2O3, HfO2, and composite HfO2/Al2O3 films were deposited on n-type GaN using atomic layer deposition (ALD). The interfacial layer of GaON and HfON was observed between HfO2 and GaN, whereas the absence of an interfacial layer at Al2O3/GaN was confirmed using X-ray photoelectron spectroscopy and transmission electron microscopy. The dielectric constants of Al2O3, HfO2, and composite HfO2/Al2O3 calculated from the C-V measurement are 9, 16.5, and 13.8, respectively. The Al2O3 employed as a template in the composite structure has suppressed the interfacial layer formation during the subsequent ALD-HfO2 and effectively reduced the gate leakage current. While the dielectric constant of the composite HfO2/Al2O3 film is lower than that of HfO2, the composite structure provides sharp oxide/GaN interface without interfacial layer, leading to better electrical properties. 相似文献
248.
Baeyens Y. Dorschky C. Weimann N. Qinghung Lee Kopf R. Georgiou G. Mattia J.P. Hamm R. Young-Kai Chen 《Microwave Theory and Techniques》2000,48(12):2403-2408
Compact monolithic integrated differential voltage-controlled oscillators (VCOs) operating in W-band were realized using InP-based heterojunction bipolar transistors (HBTs). The oscillators, with a total chip size of 0.6 by 0.35 mm2, are based on a balanced Colpitts-type topology with a coplanar transmission-line resonator. By varying the voltage across the base-collector junction of the HBT in the current mirror and by changing the current in the VCO, the oscillation frequency can be tuned between 84 and 106 GHz. At 100 GHz, a differential voltage swing of 400 mV is obtained, which should be sufficient to drive 100 Gb/s digital logic. By combining the balanced outputs of a similar differential VCO in a push-push configuration, a compact source with close to -10 dBm output power and a tuning range between 138 and 150 GHz is obtained 相似文献
249.
In this paper, the threshold voltage instability characteristics of HfO2 high-k dielectric are discussed. The results from various stress bias conditions including DC and AC with variations of frequency, duty cycle, and polarity provide additional insights into the intrinsic behavior and the trapping dynamics of high-k materials. A reduced threshold voltage shift was observed at higher frequency and lower duty cycle under AC positive unipolar stress compared to DC stress. Similarly, the degradation of maximum transconductance was also reduced with AC stress. However, subthreshold swing changes were found to be negligible and fairly independent of stress frequencies and duty cycles under AC positive unipolar stress.When different polarity of stress, such as positive, negative, and bipolar stress was applied, it was observed that frequency and duty cycle dependencies were still valid in all three conditions. In contrast to positive stress, negative stress showed a decrease in the threshold voltage shift. Bipolar stress resulted in the highest threshold voltage instability, but the degradation in transconductance and subthreshold swing was actually smaller than those in negative unipolar stress. The bulk trap of HfO2 dielectric, which is proportional to its physical thickness, is believed to be the primary factor for threshold voltage shift. AC unipolar operation would allow a higher 10-year lifetime operating voltage than the DC condition. In addition to experimental results, a plausible mechanism has been proposed. 相似文献
250.
Jong Duk Lee Sung Hun Jin Byung Chang Shim Byung-Gook Park 《Electron Device Letters, IEEE》2001,22(4):173-175
A novel process utilizing electrical stress is proposed for the formation of Co silicide on single crystal silicon (c-Si) FEAs to improve the field emission characteristics. Co silicide FEAs formed by electrical stress (ES) exhibited a significant improvement in turn-on voltage and emission current compared with c-Si FEAs. The improvement mainly comes from the lower effective work function of Co silicide and less blunting of tips during silicidation by electrical stress in an ultra high vacuum (UHV) environment less than 10-8 torr 相似文献