Improving the stability of lead halide perovskite quantum dots (QDs) in a system containing water is the key for their practical application in artificial photosynthesis. Herein, we encapsulate ...low‐cost CH3NH3PbI3 (MAPbI3) perovskite QDs in the pores of earth‐abundant Fe‐porphyrin based metal organic framework (MOF) PCN‐221(Fex) by a sequential deposition route, to construct a series of composite photocatalysts of MAPbI3@PCN‐221(Fex) (x=0–1). Protected by the MOF the composite photocatalysts exhibit much improved stability in reaction systems containing water. The close contact of QDs to the Fe catalytic site in the MOF, allows the photogenerated electrons in the QDs to transfer rapidly the Fe catalytic sites to enhance the photocatalytic activity for CO2 reduction. Using water as an electron source, MAPbI3@PCN‐221(Fe0.2) exhibits a record‐high total yield of 1559 μmol g−1 for photocatalytic CO2 reduction to CO (34 %) and CH4 (66 %), 38 times higher than that of PCN‐221(Fe0.2) in the absence of perovskite QDs.
Pores and dots: CH3NH3PbI3 (MAPbI3) perovskite quantum dots were encapsulated in the pores of iron‐porphyrin derived metal–organic frameworks (MOFs) of PCN‐221(Fex) to give an efficient photocatalytic system, which has significantly enhanced catalytic efficiency and stability for visible‐light‐driven CO2 reduction using water as an electron source.
The judicious design of efficient electron mediators to accelerate the interfacial charge transfer in a Z‐scheme system is one of the viable strategies to improve the performance of photocatalysts ...for artificial photosynthesis. Herein, ultrathin and small‐size graphene oxide (USGO) nanosheets are constructed and employed as the electron mediator to elaborately exploit an efficient CsPbBr3‐based all‐solid‐state Z‐scheme system in combination with α‐Fe2O3 for visible‐light‐driven CO2 reduction with water as the electron source. CsPbBr3 and α‐Fe2O3 can be closely anchored on USGO nanosheets, owing to the existence of interfacial strong chemical bonding behaviors, which can significantly accelerate the photogenerated carrier transfer between CsPbBr3 and α‐Fe2O3. The resultant improved charge separation efficiency endows the Z‐scheme system exhibiting a record‐high electron consumption rate of 147.6 µmol g−1 h−1 for photocatalytic CO2‐to‐CO conversion concomitant with stoichiometric O2 from water oxidation, which is over 19 and 12 times higher than that of pristine CsPbBr3 nanocrystals and the mixture of CsPbBr3 and α‐Fe2O3, respectively. This work provides a novel and effective strategy for improving the catalytic activity of halide‐perovskite‐based photocatalysts, promoting their practical applications in the field of artificial photosynthesis.
An efficient halide perovskite–based all‐solid‐state Z‐scheme system is successfully fabricated by employing ultrathin and small‐size graphene oxide (USGO) as electron mediator, which achieves a record‐high electron consumption rate of 147.6 µmol g−1 h−1 for photocatalytic CO2‐to‐CO conversion, owing to the facilitation of USGO to the interfacial charge transfer between semiconductors.
Lead halide perovskite (LHP) nanocrystals have recently been actively investigated for photocatalysis, owing to their inexpensive fabrication and excellent optoelectronic properties. However, LHP ...nanocrystals have not been used for artificial photosynthesis in aqueous solution, owing to their high sensitivity to water. In this study, water‐tolerant cobalt‐doped CsPbBr3/Cs4PbBr6 nanocrystals have been prepared with the protection of hexafluorobutyl methacrylate. The resultant materials are employed as efficient photocatalysts for visible‐light‐driven CO2 reduction in pure water. The perovskite nanocrystals with 2 % cobalt doping afford an impressive overall yield of 247 μmol g−1 for photocatalytic CO2 conversion into CO and CH4, using water as an electron source. This study represents a significant step for practical artificial photosynthesis by using LHP nanocrystals as photocatalysts in aqueous solution.
No sacrifices made: Low‐cost and water‐soluble lead halide perovskite nanocrystals with metal cation doping are fabricated with the assistance of a fluorocarbon agent. They exhibit not only high dispersity and stability in aqueous solution, but also efficient photocatalytic activity for visible‐light‐driven CO2 reduction in pure water without additional sacrificial reductant.
The ongoing increasing traffic in the era of big data yields unprecedented demands in user experience and network capacity expansion. The users of next generation mobile networks (5 G) should be able ...to use 3GPP, IEEE, and other technologies simultaneously. The integration of multiple radio access technologies (RATs) of licensed or unlicensed bands has been widely deemed as a cost-efficient way to greatly increase the network capacity. In this paper, we propose a smart aggregated RAT access (SARA) strategy with aim of maximizing the long-term network throughput while meeting diverse traffic quality of service (QoS) requirements. We consider the scenario that users with different QoS requirements access to a heterogeneous network with coexisting cellular-WiFi. In order to maximize system throughput while meeting diverse traffic QoS requirements in such a complex and dynamic environment, we exploit multiagent reinforcement learning to perform RAT selection in conjunction with resource allocation for individual user access requests, through sensing dynamic channel states and traffic QoS requirements. In SARA, we first use Nash Q-learning to provide a set of feasible RAT selection strategies while decreasing the strategy space in learning process, and then employ Monte Carlo tree search (MCTS) based Q-learning to perform resource allocation. Numerical results reveal that the network throughput can be maximized while meeting various traffic QoS requirements with limited number of searches by using our proposed SARA algorithm. For bulk arrival access requests, a suboptimal solution can be obtained as high computational complexity is incurred for achieving global optimality. Another attractive feature of SARA is that a tradeoff between the solution optimality and learning time can be readily made by terminating the search of MCTS according to the time constraint. Compared with traditional WiFi offloading schemes, SARA can significantly improve network throughput while guaranteeing traffic QoS requirements.
There exist differences in the epidemiological characteristics, clinicopathological features, tumor biological characteristics, treatment patterns, and drug selections between gastric cancer patients ...from the Eastern and Western countries. The Chinese Society of Clinical Oncology (CSCO) has organized a panel of senior experts specializing in all sub‐specialties of gastric cancer to compile a clinical guideline for the diagnosis and treatment of gastric cancer since 2016 and renews it annually. Taking into account regional differences, giving full consideration to the accessibility of diagnosis and treatment resources, these experts have conducted expert consensus judgment on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes in China. The 2021 CSCO Clinical Practice Guidelines for Gastric Cancer covers the diagnosis, treatment, follow‐up, and screening of gastric cancer. Based on the 2020 version of the CSCO Chinese Gastric Cancer guidelines, this updated guideline integrates the results of major clinical studies from China and overseas for the past year, focused on the inclusion of research data from the Chinese population for more personalized and clinically relevant recommendations. For the comprehensive treatment of non‐metastatic gastric cancer, attentions were paid to neoadjuvant treatment. The value of perioperative chemotherapy is gradually becoming clearer and its recommendation level has been updated. For the comprehensive treatment of metastatic gastric cancer, recommendations for immunotherapy were included, and immune checkpoint inhibitors from third‐line to the first‐line of treatment for different patient groups with detailed notes are provided.
The Chinese Society of Clinical Oncology (CSCO) organized a panel of senior experts specializing in all sub‐specialties of gastric cancer to compile the clinical guideline for gastric cancer in 2016 and then renewed it every year. The 2021 CSCO Clinical Practice Guidelines for gastric cancer covered the diagnosis, treatment, follow‐up and screening.
It is widely acknowledged that network slicing can tackle the diverse use cases and connectivity services of the forthcoming next-generation mobile networks (5G). Resource scheduling is of vital ...importance for improving resource-multiplexing gain among slices while meeting specific service requirements for radio access network (RAN) slicing. Unfortunately, due to the performance isolation, diversified service requirements, and network dynamics (including user mobility and channel states), resource scheduling in RAN slicing is very challenging. In this paper, we propose an intelligent resource scheduling strategy (iRSS) for 5G RAN slicing. The main idea of an iRSS is to exploit a collaborative learning framework that consists of deep learning (DL) in conjunction with reinforcement learning (RL). Specifically, DL is used to perform large time-scale resource allocation, whereas RL is used to perform online resource scheduling for tackling small time-scale network dynamics, including inaccurate prediction and unexpected network states. Depending on the amount of available historical traffic data, an iRSS can flexibly adjust the significance between the prediction and online decision modules for assisting RAN in making resource scheduling decisions. Numerical results show that the convergence of an iRSS satisfies online resource scheduling requirements and can significantly improve resource utilization while guaranteeing performance isolation between slices, compared with other benchmark algorithms.
Circular RNAs (circRNAs) regulate various biological activities and have been shown to play crucial roles in hepatocellular carcinoma (HCC) progression. However, only a few coding circRNAs have been ...identified in cancers, and their roles in HCC remain elusive. This study aimed to identify coding circRNAs and explore their function in HCC.
CircMAP3K4 was selected from the CIRCpedia database. We performed a series of experiments to determine the characteristics and coding capacity of circMAP3K4. We then used in vivo and in vitro assays to investigate the biological function and mechanism of circMAP3K4 and its protein product, circMAP3K4-455aa, in HCC.
We found circMAP3K4 to be an upregulated circRNA with coding potential in HCC. IGF2BP1 recognized the circMAP3K4 N6-methyladenosine modification and promoted its translation into circMAP3K4-455aa. Functionally, circMAP3K4-455aa prevented cisplatin-induced apoptosis in HCC cells by interacting with AIF, thus protecting AIF from cleavage and decreasing its nuclear distribution. Moreover, circMAP3K4-455aa was degraded through the ubiquitin-proteasome E3 ligase MIB1 pathway. Clinically, a high level of circMAP3K4 is an independent prognostic factor for adverse overall survival and adverse disease-free survival of HCC patients.
CircMAP3K4 is a highly expressed circRNA in HCC. Driven by m6A modification, circMAP3K4 encoded circMAP3K4-455aa, protected HCC cells from cisplatin exposure, and predicted worse prognosis of HCC patients. Targeting circMAP3K4-455aa may provide a new therapeutic strategy for HCC patients, especially for those with chemoresistance. CircMAP3K4 is a highly expressed circRNA in HCC. Driven by m6A modification, IGF2BP1 facilitates circMAP3K4 peptide translation, then the circMAP3K4 peptide inhibits AIF cleavage and nuclear distribution, preventing HCC cells from cell death under stress and promoting HCC progression.
Capping ligands are indispensable for the preparation of metal‐halide‐perovskite (MHP) nanocrystals (NCs) with good stability; however, the long alkyl‐chain capping ligands in conventional MHP NCs ...will be unfavorable for CO2 adsorption and hinder the efficient carrier separation on the surface of MHP NCs, leading to inferior catalytic activity in artificial photosynthesis. Herein, CsPbBr3 nanocrystals with short‐chain glycine as ligand are constructed through a facile ligand‐exchange strategy. Owing to the reduced hindrance of glycine and the presence of the amine group in glycine, the photogenerated carrier separation and CO2 uptake capacity are noticeably improved without compromising the stability of the MHP NCs. The CsPbBr3 nanocrystals with glycine ligands exhibit a significantly increased yield of 27.7 μmol g−1 h−1 for photocatalytic CO2‐to‐CO conversion without any organic sacrificial reagents, which is over five times higher than that of control CsPbBr3 NCs with conventional long alkyl‐chain capping ligands.
Ligand exchange: Glycine‐functionalized CsPbBr3 nanocrystals are constructed through a facile ligand‐exchange strategy. They exhibit a significantly improved yield of 27.7 μmol g−1 h−1 for photocatalytic CO2‐to‐CO conversion coupled with water oxidation, which is over five times higher than that of control CsPbBr3 with conventional long alkyl‐chain capping ligands.
The prognostic value and clinical relevance of tertiary lymphoid structures (TLSs) in intrahepatic cholangiocarcinoma (iCCA) remain unclear. Thus, we aimed to investigate the prognostic value and ...functional involvement of TLSs in iCCA.
We retrospectively included 962 patients from 3 cancer centers across China. The TLSs at different anatomic subregions were quantified and correlated with overall survival (OS) by Cox regression and Kaplan-Meier analyses. Multiplex immunohistochemistry (mIHC) was applied to characterize the composition of TLSs in 39 iCCA samples.
A quaternary TLS scoring system was established for the intra-tumor region (T score) and peri-tumor region (P score) respectively. T scores positively correlated with favorable prognosis (p <0.001), whereas a high P score signified worse survival (p <0.001). mIHC demonstrated that both T follicular helper and regulatory T cells were significantly increased in intra-tumoral TLSs compared to peri-tumoral counterparts (p <0.05), and regulatory T cell frequencies within intra-tumoral TLSs were positively associated with P score (p <0.05) rather than T score. Collectively, the combination of T and P scores stratified iCCAs into 4 immune classes with distinct prognoses (p <0.001) that differed in the abundance and distribution pattern of TLSs. Patients displaying an immune-active pattern had the lowest risk, with 5-year OS rates of 68.8%, whereas only 3.4% of patients with an immune-excluded pattern survived at 5 years (p <0.001). The C-index of the immune class was statistically higher than the TNM staging system (0.73 vs. 0.63, p <0.001). These results were validated in an internal and 2 external cohorts.
The spatial distribution and abundance of TLSs significantly correlated with prognosis and provided a useful immune classification for iCCA. T follicular helper and regulatory T cells may play a critical role in determining the functional orientation of spatially different TLSs.
Tertiary lymphoid structures (TLSs) are associated with favorable prognosis in a number of cancers. However, their role in intrahepatic cholangiocarcinoma (iCCA) remains unclear. Herein, we comprehensively evaluated the spatial distribution, abundance, and cellular composition of TLSs in iCCA, and revealed the opposite prognostic impacts of TLSs located within or outside the tumor. This difference could be mediated by the different immune cell subsets present within the spatially distinct TLSs. Based on our analysis, we were able to stratify iCCAs into 4 immune subclasses associated with varying prognoses.
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•Tertiary lymphoid structures (TLSs) within and outside the tumor have opposite prognostic impacts on patients with iCCA.•The heterogeneous distribution of Tfh and Treg cells within distinct TLSs might be a determinant of their functional state.•The geographic integration of TLSs stratified iCCAs into 4 immune subclasses with distinct clinical outcomes.
The next-generation mobile communication system fifth-generation (5G) needs to address the challenges stemming from the performance requirements in diverse technical scenarios, such as seamless ...wide-area coverage, high-capacity hot-spots, and low-power massive connections. It is widely recognized that traditional single-tier cellular network architecture is not adequate to meet these requirements, and thus, the heterogeneous cellular network (HetNet) has been identified as a promising network architecture for 5G. In HetNets, traffic offloading can be exploited to effectively improve network capacity by utilizing complementary network communication techniques. In this paper, we propose a device-to-device (D2D) communication assisted mobile traffic offloading (DATO) scheme, with focus on massive connections for machine type communications (MTC). DATO determines access mode for user equipments (UEs) to offload UEs from macro base stations (MBSs) to small base stations via D2D communications to improve the overall network capacity and mitigate the traffic congestion at MBSs. We formulate the DATO problem as a 0-1 linear programing and prove it to be NP-hard. We resort to dynamic programing to provide the optimal solution, as well as the theoretical performance upper bound of DATO. We develop an efficient algorithm to solve the DATO problem while preserving the optimality by making use of the location relationship of BSs and UEs. We apply our proposed DATO scheme to a series of typical network scenarios to validate its effectiveness. Numerical results reveal that DATO significantly outperforms traditional UE access mode in terms of network capacity and UE energy consumption, which are important to massive MTC.
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