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Lithium-sulfur batteries hold broad prospects as the low-cost and high-energy storage system. However, the practical application is limited by the intrinsic insulating nature of sulfur and severe shuttle effect of soluble polysulfide intermediates. Herein, we demonstrate a convenient self-assembly strategy for encapsulating carbon nanotubes in nitrogen-doped hollow carbon shells, to construct a nitrogen-doped tube-in-tube carbon nanostructure (NTTC) as a host material of sulfur. In this peculiar structure, the highly conductive carbon nanotube cores facilitate the electron transfer while the hollow porous structure is capable of accommodating high sulfur content of 70 wt% in the composites. Moreover, the nitrogen doping helps to alleviate the shuttle effect owing to enhanced chemisorption towards polysulfides. Benefiting from these merits, the NTTC/S composite with the high areal mass loading of ~2.5 mg cm−2 presents a high reversible capacity (1346.9 mAh g−1 at 0.05 C) and excellent rate capability (533.5 mAh g−1 at 3C). More impressively, NTTC/S electrode exhibits good cycling stability at a high rate of 2 C corresponding to slight capacity decay of 0.055% per cycle over 500 discharge/charge cycles. [ABSTRACT FROM AUTHOR]

Surgery, radiotherapy and chemotherapy are the mainstay of malignant cancer treatments. However, with the development of immunology, the emerging immunotherapy represents a rational and alternative approach for the treatment of human cancer, including ovarian cancer (OC). Based on a body of evidence and the clinical success of immunotherapy in many malignancies, it is confirmed that blocking the programmed death 1 (PD-1) and its ligands in OC is feasible and valid both in animal models and patients. Immunotherapy may play a significant role in the future clinical management and improve the prognosis of OC. This review will focus on the biological functions, treatment response, toxicity and viable target of PD-1 and its ligands in OC. Recognition of the multiple functions of PD-1 and its ligands in ovarian cancer will serve to deepen our understanding of the nature of OC, develop novel immunotherapy approaches and discover possible diagnostic and prognostic biomarkers in future clinical decisions. [ABSTRACT FROM AUTHOR]

Abstract: Although controlled biomedical terminologies have been with us for centuries, it is only in the last couple of decades that close attention has been paid to the quality of these terminologies. The result of this attention has been the development of auditing methods that apply formal methods to assessing whether terminologies are complete and accurate. We have performed an extensive literature review to identify published descriptions of these methods and have created a framework for characterizing them. The framework considers manual, systematic and heuristic methods that use knowledge (within or external to the terminology) to measure quality factors of different aspects of the terminology content (terms, semantic classification, and semantic relationships). The quality factors examined included concept orientation, consistency, non-redundancy, soundness and comprehensive coverage. We reviewed 130 studies that were retrieved based on keyword search on publications in PubMed, and present our assessment of how they fit into our framework. We also identify which terminologies have been audited with the methods and provide examples to illustrate each part of the framework. [Copyright &y& Elsevier]

Incorporation of lanthanide atom into the titanium−oxo cluster structure is an effective strategy for exploring novel photoelectrode materials. Herein, we synthesized and characterized three lanthanide-doped titanium−oxo clusters (Ln-TOCs): [Ti 4 La(μ 3 -O) 3 (O i Pr) 2 (C 6 H 5 COO) 11 ]·3CH 3 CN (1), [Ti 4 Eu 2 (μ 3 -O) 4 (acac) 2 (C 6 H 5 COO) 13 ] (2, acac ​= ​acetylacetonate), and [Ti 7 Ce(μ 2 -O) 2 (μ 3 -O) 5 (O i Pr) 2 (C 6 H 5 COO) 15 ]·CH 3 CN (3). These Ln−TOCs display strong UV-light absorption and extended visible light absorption, which can be ascribed to the doping of lanthanides and benzoates. As electrode precursors for photoelectric responses, these Ln doped clusters exhibit clear photocurrent responses. Moreover, cluster 3 shows the highest photocurrent intensity because of Ce(IV)/Ce(III) redox reaction. This work not only enriches the Ln−TOCs family, but also promotes the development of novel titanium-based photoelectric active materials. We successfully synthesized three lanthanide-doped titanium-oxo clusters, and their clear photocurrent responses were observed. [Display omitted] • Three lanthanide-doped titanium-oxo clusters were synthesized and characterized. • Lanthanide doping effectively improves the light absorption of these materials. • These materials as electrode precursors exhibit clear photocurrent responses. • Ce-doped titanium-oxo cluster displays the highest photocurrent intensity. [ABSTRACT FROM AUTHOR]

[Display omitted] Committed to improving the utilization efficiency of Pt atoms and accurately controlling the morphology and composition of nanocatalysts to boost the Pt-based catalyst performance has become the focus of research. Herein, the PtRhNi truncated triangular nanoflakes (TA-NFs) catalyst with a unique PtRh-rich surface structure was successfully prepared by an effective one-pot synthetic method based on the galvanic replace reaction. The freestanding 2D nanostructure of PtRhNi TA-NFs, intrinsically possessing much high specific surface area and surface atomic, and the PtRh-rich characteristics of the surface is undoubtedly the most feasible model to simultaneously achieve high atom utilization. Benefiting from this novel structure, the as-obtained PtRhNi TA-NFs nanocatalyst exhibits excellent performance for ORR and MOR, delivering a mass activity of 0.92 A mg pt -1 for ORR, which is 2.03, 1.64, and 6.9-fold higher than that of PtRhNi nanoparticls (NPs), PtNi truncated triangle nanoflakes (TA-NFs) and commercial Pt/C, respectively. In addition, after 20 k cycles ADT test, PtRhNi TA-NFs show only 10 mV negative shift of half-wave potential and retain 70% of initial value of mass activity. Furthermore, a mass activity is 1.28 A mg pt −1 is achieved after applying this unique nanocatalyst for MOR, which is 1.28,1.5, and 2.6 times higher than that of PtRhNi NPs, PtNi TA-NFs and Pt/C, respectively. Impressively, the PtRhNi TA-NFs nanocatalyst shows an ultrahigh stability even after 2 k cycles ADT measurement in acid solution, and the mass activity is only drop 2% of initial value. This work provides a new strategy to synthesis high-performance of bifunction Pt-based electrocatalyst for ORR and MOR fuel cells. [ABSTRACT FROM AUTHOR]

[Display omitted] Ammonia oxidation reaction (AOR) via electrocatalysis is one of the most efficient ways of utilizing ammonia (a zero-carbon fuel with high hydrogen content) for renewable energy systems. However, AOR seriously suffers from the slow kinetics, and low durability due to its multi-electron transfer process and the poison of the reaction intermediates (N ads and NO ads) to precious metal catalysts. Herein, hyperbranched concave octahedral nanodendrites of PtIrCu (HCOND) with high-index facets of {5 5 3}, {3 3 1} and {2 2 1} were developed for the first time using a solvothermal method. The HCOND possesses PtIr-rich edges and exhibit highly efficient AOR activity and stability in alkaline media, wherein their onset potential is 0.35 V vs. RHE, which is 60 mV and 160 mV lower than that of the PtIrCu nanoparticles (NPs) (0.41 V) and commercial Pt/C (0.51 V), respectively, and its high mass activity of 40.6 A g PtIr -1 at the 0.5 V vs. RHE is 10.3 times, 2.34 times higher than that of commercial Pt/C (3.9 A g Pt -1) and PtIrCu NPs (17.3 A g PtIr –1), respectively. In addition, its peak current density (122.9 A g PtIr -1) is only reduced by 17.7% after 2000-cycles accelerated durability test. Meanwhile, the performance of PtIrCu HCOND is also better than that of other previously reported morphologies of Pt based catalysts (eg. nanoparticles, nanocubes, nanofilm, nanoflowers). The improvement is critically ascribed to unique advantages of the specific HCOND structure including PtIr rich surface, high-index faceted nanodendrites, strong lattice strain and electronic effects. These characteristics endow the HCOND with great promise to reduce Pt and Ir loading dramatically in the practical application of direct ammonia fuel cells. [ABSTRACT FROM AUTHOR]