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991.
992.
Hathaichanok Phuengkham Long Ren Il Woo Shin Yong Taik Lim 《Advanced materials (Deerfield Beach, Fla.)》2019,31(34)
Cancer immunotherapies that harness the body's immune system to combat tumors have received extensive attention and become mainstream strategies for treating cancer. Despite promising results, some problems remain, such as the limited patient response rate and the emergence of severe immune‐related adverse effects. For most patients, the therapeutic efficacy of cancer immunotherapy is mainly limited by the immunosuppressive tumor microenvironment (TME). To overcome such obstacles in the TME, the immunomodulation of immunosuppressive factors and therapeutic immune cells (e.g., T cells and antigen‐presenting cells) should be carefully designed and evaluated. Nanoengineered synthetic immune niches have emerged as highly customizable platforms with a potent capability for reprogramming the immunosuppressive TME. Here, recent developments in nano‐biomaterials that are rationally designed to modulate the immunosuppressive TME in a spatiotemporal manner for enhanced cancer immunotherapy which are rationally designed to modulate the immunosuppressive TME in a spatiotemporal manner for enhanced cancer immunotherapy are highlighted. 相似文献
993.
Jung Hwa Kim Se‐Yang Kim Yeonchoo Cho Hyo Ju Park Hyeon‐Jin Shin Soon‐Yong Kwon Zonghoon Lee 《Advanced materials (Deerfield Beach, Fla.)》2019,31(15)
Van der Waals (vdW) epitaxy allows the fabrication of various heterostructures with dramatically released lattice matching conditions. This study demonstrates interface‐driven stacking boundaries in WS2 using epitaxially grown tungsten disulfide (WS2) on wrinkled graphene. Graphene wrinkles function as highly reactive nucleation sites on WS2 epilayers; however, they impede lateral growth and induce additional stress in the epilayer due to anisotropic friction. Moreover, partial dislocation‐driven in‐plane strain facilitates out‐of‐plane buckling with a height of 1 nm to release in‐plane strain. Remarkably, in‐plane strain relaxation at partial dislocations restores the bandgap to that of monolayer WS2 due to reduced interlayer interaction. These findings clarify significant substrate morphology effects even in vdW epitaxy and are potentially useful for various applications involving modifying optical and electronic properties by manipulating extended 1D defects via substrate morphology control. 相似文献
994.
Hui Gao Jeongyeon Lee Qixiao Lu Yoonbin Kim Kang Ho Shin Ho Seok Park Zhonghua Zhang Lawrence Yoon Suk Lee 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(4):2205681
Potassium- and sodium-ion batteries (PIBs and SIBs) have great potential as the next-generation energy application owing to the natural abundance of K and Na. Antimony (Sb) is a suitable alloying-type anode for PIBs and SIBs due to its high theoretical capacity and proper operation voltage; yet, the severe volume variation remains a challenge. Herein, a preparation of N-doped carbon-wrapped Sb nanoparticles (L-Sb/NC) using pulsed laser ablation and polydopamine coating techniques, is reported. As the anode for PIB and SIB, the L-Sb/NC delivers superior rate capabilities and excellent cycle stabilities (442.2 and 390.5 mA h g−1 after 250 cycles with the capacity decay of 0.037% and 0.038% per cycle) at the current densities of 0.5 and 1.0 A g−1, respectively. Operando X-ray diffraction reveals the facilitated and stable potassiation and sodiation mechanisms of L-Sb/NC enabled by its optimal core–shell structure. Furthermore, the SIB full cell fabricated with L-Sb/NC and Na3V2(PO4)2F3 shows outstanding electrochemical performances, demonstrating its practical energy storage application. 相似文献
995.
Jihun Kim Jun Sung Jang Seung Wook Shin Hyeonghun Park Woo-Lim Jeong Seung-Hyun Mun Jung-Hong Min Jiyoung Ma Jaeyeong Heo Dong Seon Lee Jung-Je Woo Jin Hyeok Kim Hyeong-Jin Kim 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(22):2370156
Herein, a novel combination of Mg- and Ga-co-doped ZnO (MGZO)/Li-doped graphene oxide (LGO) transparent electrode (TE)/electron-transporting layer (ETL) has been applied for the first time in Cu2ZnSn(S,Se)4 (CZTSSe) thin-film solar cells (TFSCs). MGZO has a wide optical spectrum with high transmittance compared to that with conventional Al-doped ZnO (AZO), enabling additional photon harvesting, and has a low electrical resistance that increases electron collection rate. These excellent optoelectronic properties significantly improved the short-circuit current density and fill factor of the TFSCs. Additionally, the solution-processable alternative LGO ETL prevented plasma-induced damage to chemical bath deposited cadmium sulfide (CdS) buffer, thereby enabling the maintenance of high-quality junctions using a thin CdS buffer layer (≈30 nm). Interfacial engineering with LGO improved the Voc of the CZTSSe TFSCs from 466 to 502 mV. Furthermore, the tunable work function obtained through Li doping generated a more favorable band offset in CdS/LGO/MGZO interfaces, thereby, improving the electron collection. The MGZO/LGO TE/ETL combination achieved a power conversion efficiency of 10.67%, which is considerably higher than that of conventional AZO/intrinsic ZnO (8.33%). 相似文献
996.
Yong Cheol Shin Jung Bok Lee Dae‐Hyun Kim Taeyoung Kim Grant Alexander Young Min Shin Ju Young Park Sewoom Baek Jeong‐Kee Yoon Yong Jae Lee Gyeung Mi Seon Mi Hee Lee Mi‐Lan Kang Woo Soon Jang Jong‐Chul Park Ho‐Wook Jun YongTae Kim Hak‐Joon Sung 《Advanced materials (Deerfield Beach, Fla.)》2019,31(41)
Inserting a graft into vessels with different diameters frequently causes severe damage to the host vessels. Poor flow patency is an unresolved issue in grafts, particularly those with diameters less than 6 mm, because of vessel occlusion caused by disturbed blood flow following fast clotting. Herein, successful patency in the deployment of an ≈2 mm diameter graft into a porcine vessel is reported. A new library of property‐tunable shape‐memory polymers that prevent vessel damage by expanding the graft diameter circumferentially upon implantation is presented. The polymers undergo seven consecutive cycles of strain energy‐preserved shape programming. Moreover, the new graft tube, which features a diffuser shape, minimizes disturbed flow formation and prevents thrombosis because its surface is coated with nitric‐oxide‐releasing peptides. Improved patency in a porcine vessel for 18 d is demonstrated while occlusive vascular remodeling occurs. These insights will help advance vascular graft design. 相似文献
997.
Da Luo Meihui Wang Yunqing Li Changsik Kim Ka Man Yu Yohan Kim Huijun Han Mandakini Biswal Ming Huang Youngwoo Kwon Min Goo Dulce C. Camacho‐Mojica Haofei Shi Won Jong Yoo Michael S. Altman Hyung‐Joon Shin Rodney S. Ruoff 《Advanced materials (Deerfield Beach, Fla.)》2019,31(35)
To date, thousands of publications have reported chemical vapor deposition growth of “single layer” graphene, but none of them has described truly single layer graphene over large area because a fraction of the area has adlayers. It is found that the amount of subsurface carbon (leading to additional nuclei) in Cu foils directly correlates with the extent of adlayer growth. Annealing in hydrogen gas atmosphere depletes the subsurface carbon in the Cu foil. Adlayer‐free single crystal and polycrystalline single layer graphene films are grown on Cu(111) and polycrystalline Cu foils containing no subsurface carbon, respectively. This single crystal graphene contains parallel, centimeter‐long ≈100 nm wide “folds,” separated by 20 to 50 µm, while folds (and wrinkles) are distributed quasi‐randomly in the polycrystalline graphene film. High‐performance field‐effect transistors are readily fabricated in the large regions between adjacent parallel folds in the adlayer‐free single crystal graphene film. 相似文献
998.
Y Namkung SM Smith SB Lee NV Skrypnyk HL Kim H Chin RH Scheller RW Tsien HS Shin 《Canadian Metallurgical Quarterly》1998,95(20):12010-12015
In comparison to the well characterized role of the principal subunit of voltage-gated Ca2+ channels, the pore-forming, antagonist-binding alpha1 subunit, considerably less is understood about how beta subunits contribute to neuronal Ca2+ channel function. We studied the role of the Ca2+ channel beta3 subunit, the major Ca2+ channel beta subunit in neurons, by using a gene-targeting strategy. The beta3 deficient (beta3-/-) animals were indistinguishable from the wild type (wt) with no gross morphological or histological differences. However, in sympathetic beta3-/- neurons, the L- and N-type current was significantly reduced relative to wt. Voltage-dependent activation of P/Q-type Ca2+ channels was described by two Boltzmann components with different voltage dependence, analogous to the "reluctant" and "willing" states reported for N-type channels. The absence of the beta3 subunit was associated with a hyperpolarizing shift of the "reluctant" component of activation. Norepinephrine inhibited wt and beta3-/- neurons similarly but the voltage sensitive component was greater for N-type than P/Q-type Ca2+ channels. The reduction in the expression of N-type Ca2+ channels in the beta3-/- mice may be expected to impair Ca2+ entry and therefore synaptic transmission in these animals. This effect may be reversed, at least in part, by the increase in the proportion of P/Q channels activated at less depolarized voltage levels. 相似文献
999.
Kun Yin Hung‐Yuan Lin Shin‐Tson Wu 《Journal of the Society for Information Display》2020,28(4):368-374
We demonstrate a reflective chirped polarization volume grating as a strong contender for wide field‐of‐view augmented reality display systems. By introducing gradient pitch along the beam propagation direction, the angular bandwidth extends dramatically from 18° to 54° while keeping over 80% average efficiency and 95% peak efficiency. 相似文献
1000.
Shin Jungpil Islam Md Rashedul Rahim Md Abdur Mun Hyung-Jin 《Peer-to-Peer Networking and Applications》2020,13(2):635-646
Peer-to-Peer Networking and Applications - User authentication has become an essential security element that enables a wide range of applications in P2P systems for higher security and safety... 相似文献