Herein, we employ a galvanic replacement approach to create atomically dispersed Au on degradable zero-valent Cu nanocubes for tumor treatments on female mice. Controlling the addition of precursor ...HAuCl
allows for the fabrication of different atomic ratios of Au
Cu
. X-ray absorption near edge spectra indicates that Au and Cu are the predominant oxidation states of zero valence. This suggests that the charges of Au and Cu remain unchanged after galvanic replacement. Specifically, Au
Cu
composition reveals the enhanced •OH generation following O
→ H
O
→ •OH. The degradable Au
Cu
released Cu
and Cu
resulting in oxygen reduction and Fenton-like reactions. Simulation studies indicate that Au single atoms boot zero-valent copper to reveal the catalytic capability of Au
Cu
for O
→ H
O
→ •OH as well. Instead of using endogenous H
O
, H
O
can be sourced from the O
in the air through the use of nanocubes. Notably, the Au
Cu
structure is degradable and renal-clearable.
Abstract
Designing efficient catalyst for the oxygen evolution reaction (OER) is of importance for energy conversion devices. The anionic redox allows formation of O-O bonds and offers higher OER ...activity than the conventional metal sites. Here, we successfully prepare LiNiO
2
with a dominant 3
d
8
L
configuration (
L
is a hole at O 2
p
) under high oxygen pressure, and achieve a double ligand holes 3
d
8
L
2
under OER since one electron removal occurs at O 2
p
orbitals for Ni
III
oxides. LiNiO
2
exhibits super-efficient OER activity among LiMO
2
,
R
MO
3
(M = transition metal,
R
= rare earth) and other unary 3d catalysts. Multiple in situ/operando spectroscopies reveal Ni
III
→Ni
IV
transition together with Li-removal during OER. Our theory indicates that Ni
IV
(3
d
8
L
2
) leads to direct O-O coupling between lattice oxygen and *O intermediates accelerating the OER activity. These findings highlight a new way to design the lattice oxygen redox with enough ligand holes created in OER process.
Anion exchange membrane fuel cells are limited by the slow kinetics of alkaline hydrogen oxidation reaction (HOR). Here, we establish HOR catalytic activities of single-atom and diatomic sites as a ...function of *H and *OH binding energies to screen the optimal active sites for the HOR. As a result, the Ru-Ni diatomic one is identified as the best active center. Guided by the theoretical finding, we subsequently synthesize a catalyst with Ru-Ni diatomic sites supported on N-doped porous carbon, which exhibits excellent catalytic activity, CO tolerance, and stability for alkaline HOR and is also superior to single-site counterparts. In situ scanning electrochemical microscopy study validates the HOR activity resulting from the Ru-Ni diatomic sites. Furthermore, in situ x-ray absorption spectroscopy and computational studies unveil a synergistic interaction between Ru and Ni to promote the molecular H
dissociation and strengthen OH adsorption at the diatomic sites, and thus enhance the kinetics of HOR.
Layered transition metal (TM) oxides have aroused enormous interest in both fundamental and applied cathode material research in the context of high energy‐density batteries. Although various ...mechanisms have been proposed to explain their significant initial capacity losses, the effect of the local structural defects on performance has been largely ignored. Herein, the stacking faults are visualized and their presence is correlated with the incomplete phase transition in Li2RuO3 to understand the significant abnormal capacity loss in the first cycle. The comprehensive performance evaluation, physical characterization and theoretical calculations indicate that the two types of stacking faults, the 100//11¯0 boundaries and the 110//11¯0 boundaries, lead to sluggish lithium diffusion and increasing stacking faults deteriorates the lithium insertion dynamics. These findings are helpful to understand the performance degradation of the layer‐structured oxides in which the anionic redox or the transition metal migration is not involved in electrochemical reactions. It is hoped that this research will also inspire new ideas for designing novel cathode materials and for improving the performance of existing materials by tuning the local structures or minimizing the local structural defects.
Two types of stacking faults were visualized in Li2RuO3 by scanning transmission electron microscopy and recognized as the origin for the sluggish lithium diffusion and the resultant significant capacity loss in the first cycle on the basis of density functional theory calculations and comprehensive characterizations.
Background
We investigated the survival impact and toxicity of maintenance metronomic chemotherapy in patients with metastatic/recurrent nasopharyngeal carcinoma (met/rec NPC).
Methods
Ninety‐eight ...patients with met/rec NPC were first salvaged by IV cisplatin‐based chemotherapy and showed nonprogression disease; then maintenance metronomic chemotherapy for at least 12 months was recommended. We analyzed the treatment outcome between patients who received (n = 51) and did not receive (n = 47) maintenance chemotherapy.
Results
Baseline patient characteristics showed no significant differences between both arms. Median overall survival for patients with and without maintenance chemotherapy was 36.0 and 12.3 months, respectively (p < 0.0001). Similarly, median progression‐free survival was 24.7 and 7.3 months, respectively (p < 0.0001). Furthermore, toxicities during maintenance oral chemotherapy period were usually mild. Transient grade 3 leucopenia (9.8%), anemia (3.9%), thrombocytopenia (7.8%), and no grade 4 toxicity were observed.
Conclusion
After IV salvage chemotherapy, maintenance oral metronomic chemotherapy significantly improved overall and progression‐free survivals while demonstrating low toxicity in patients with met/rec NPC.
Taiwan is an island located in the south Pacific, a subtropical region that is home to 61 species of snakes. Of these snakes, four species-Trimeresurus stejnegeri, Protobothrops mucrosquamatus, ...Bungarus multicinctus and Naja atra-account for more than 90% of clinical envenomation cases. Currently, there are two types of bivalent antivenom: hemorrhagic antivenom against the venom of T. stejnegeri and P. mucrosquamatus, and neurotoxic antivenom for treatment of envenomation by B. multicinctus and N. atra. However, no suitable detection kits are available to precisely guide physicians in the use of antivenoms. Here, we sought to develop diagnostic assays for improving the clinical management of snakebite in Taiwan. A two-step affinity purification procedure was used to generate neurotoxic species-specific antibodies (NSS-Abs) and hemorrhagic species-specific antibodies (HSS-Abs) from antivenoms. These two SSAbs were then used to develop a sandwich ELISA (enzyme-linked immunosorbent assay) and a lateral flow assay comprising two test lines. The resulting ELISAs and lateral flow strip assays could successfully discriminate between neurotoxic and hemorrhagic venoms. The limits of quantification (LOQ) of the ELISA for neurotoxic venoms and hemorrhagic venoms were determined to be 0.39 and 0.78 ng/ml, respectively, and the lateral flow strips were capable of detecting neurotoxic and hemorrhagic venoms at concentrations lower than 5 and 50 ng/ml, respectively, in 10-15 min. Tests of lateral flow strips in 21 clinical snakebite cases showed 100% specificity and 100% sensitivity for neurotoxic envenomation, whereas the sensitivity for detecting hemorrhagic envenomation samples was 36.4%. We herein presented a feasible strategy for developing a sensitive sandwich ELISA and lateral flow strip assay for detecting and differentiating venom proteins from hemorrhagic and neurotoxic snakes. A useful snakebite diagnostic guideline according to the lateral flow strip results and clinical symptoms was proposed to help physicians to use antivenoms appropriately. The two-test-line lateral flow strip assay could potentially be applied in an emergency room setting to help physicians diagnose and manage snakebite victims.
PDF
