The development of an effective one‐photon excitation pathway to improve the charge‐carrier separation and mobility of semiconductors, which have been proven to be favorable for heterogeneous ...catalysis, is highly desirable but remains a great challenge. Herein, a high‐throughput one‐photon excitation pathway is reported by constructing 0D carbon dots/3D porous carbon nitride nanovesicles (denoted as CDs/PCN NVs) heterostructures for photocatalytic hydrogen evolution. In particular, the optimum CDs/PCN NVs heterostructures exhibit an impressive performance of 14.022 mmol h−1 g−1, which is 56.54 times higher than that of pristine CN. Detailed characterization reveals that the improved performance is primarily attributed to the high‐throughput and one‐photon excitation pathway. The former could be attributed to a great deal of CDs with high charge‐carrier mobility coupled to PCN NVs, which enable more electrons to be photoexcited via the broad absorption response, and the multiple reflection of incident light owing to the porous nanovesicle structure with shortened route of carriers migrating toward the surface; the latter would lead to the photoinduced holes and electrons accumulated at the valence band of PCN NVs and surface of CDs, respectively, achieving an effective spatial separation. The high‐throughput one‐photon excitation pathway demonstrated here may provide insights into the development of nanocomposites for various related applications.
A high‐throughput one‐photon excitation pathway is reported by constructing 0D carbon dots/3D porous carbon nitride nanovesicles (CDs/PCN NVs) heterostructures for visible‐light driven hydrogen evolution. In particular, the covalently bonded CDs on PCN NVs enable a high throughput charge migration in the wide spectrum visible light region and promote effective spatial separation via a one‐photon excitation pathway.
This paper studies the problem of multistage placement of electric vehicle (EV) charging stations with incremental EV penetration rates. A nested logit model is employed to analyze the charging ...preference of the individual consumer (EV owner) and predict the aggregated charging demand at the charging stations. The EV charging industry is modeled as an oligopoly where the entire market is dominated by a few charging service providers (oligopolists). At the beginning of each planning stage, an optimal placement policy for each service provider is obtained through analyzing strategic interactions in a Bayesian game. To derive the optimal placement policy, we consider both the transportation network graph and the electric power network graph. A simulation software - the EV Virtual City 1.0 - is developed using Java to investigate the interactions among the consumers (EV owner), the transportation network graph, the electric power network graph, and the charging stations. Through a series of experiments using the geographic and demographic data from the city of the San Pedro District of Los Angeles, CA, USA, we show that the charging station placement is highly consistent with the heatmap of the traffic flow. In addition, we observe a spatial economic phenomenon that service providers prefer clustering instead of separation in the EV charging market.
Summary The poor prognosis and rising incidence of esophageal cancer highlight the need for improved detection and prediction methods that are essential prior to treatment. Esophageal cancer is one ...of the most fatal malignancies worldwide, with a dramatic increase in incidence in the Western world occurring over the past few decades. Despite improvements in the management and treatment of esophageal cancer patients, the general outcome remains very poor for overall 5-year survival rates (∼10%) and 5-year postesophagectomy survival rates (∼15–40%). Esophageal cancer is often diagnosed during its advanced stages, the main reason being the lack of early clinical symptoms. In an attempt to improve the outcome of patients after surgery, such patients are often treated with neoadjuvent concurrent chemoradiotherapy (CCRT) in order to decrease tumor size. However, CCRT may enhance toxicity levels and possibly cause a delay in surgery for patients who respond poorly to CCRT. Thus, precise biomarkers that could predict or identify patients who may or may not respond well to CCRT can assist physicians in choosing the appropriate therapy for patients. Identifying susceptible gene and biomarkers can help in predicting the treatment response of patients while improving their survival rates.
2D amorphous transition metal oxides (a‐TMOs) heterojunctions that have the synergistic effects of interface (efficiently promoting the separation of electron−hole pairs) and amorphous nature ...(abundant defects and dangling bonds) have attracted substantial interest as compelling photocatalysts for solar energy conversion. Strategies to facilely construct a‐TMOs‐based 2D/2D heterojunctions is still a big challenge due to the difficulty of preparing individual amorphous counterparts. A generalized synthesis strategy based on supramolecular self‐assembly for bottom–up growth of a‐TMOs‐based 2D heterojunctions is reported, by taking 2D/2D g‐C3N4 (CN)/a‐TMOs heterojunction as a proof‐of‐concept. This strategy primarily depends on controlling the cooperation of the growth of supramolecular precursor and the coordinated covalent bonds arising from the tendency of metal ions to attain the stable configuration of electrons, which is independent on the intrinsic character of individual metal ion, indicating it is universally applicable. As a demonstration, the structure, physical properties, and photocatalytic water‐splitting performance of CN/a‐ZnO heterojunction are systematically studied. The optimized 2D/2D CN/a‐ZnO exhibits enhanced photocatalytic performance, the hydrogen (432.6 µmol h−1 g−1) and oxygen (532.4 µmol h−1 g−1) evolution rate are 15.5 and 12.2 times than bulk CN, respectively. This synthetic strategy is useful to construct 2D a‐TMOs nanomaterials for applications in energy‐related areas and beyond.
A generalized synthesis strategy for the bottom–up growth of amorphous transition metal oxides (a‐TMOs) 2D/2D heterojunctions with large contact area via covalent interfacial interaction is provided. A number of 2D/2D CN/a‐TMOs heterojunctions, such as CN/a‐FeOx, CN/a‐CuOx, CN/a‐MnOx, CN/a‐CoOx, and CN/a‐ZnO are successfully synthesized, which has a large and perfect order−disorder interface. Particularly, 2D/2D CN/a‐ZnO heterojunction exhibit boosted photocatalytic hydrogen and oxygen evolution.
Redox-sensitive transition group elements are involved in almost all fundamental geochemical processes. Of these elements, vanadium (V) contributes a particularly powerful tool to decipher the ...Earth's history and its link to extraterrestrial bodies. A comprehensive view of V includes the formation and interaction between the Earth's interior layers, the evolution of the Earth's surface to a habitable zone, biogeochemical cycling, and anthropogenic impacts on the environment. Tracing the geochemical behavior of V through the Earth's compartments reveals critical connections between almost all disciplines of Earth sciences. Vanadium has a history of application as a redox tracer to address the early accretion history of the Earth, to identify connections between the mantle and crust by subduction and melting, and to interpret past surface environments. The geochemical cycling of V from the deep Earth to the surface occurs through magmatism, weathering and digenesis, reflecting variations of fO2 and V species in different Earth compartments. Minerals form a link between deep Earth reservoirs of vanadium and surface environments, and the study of V in minerals has increased the understanding of V cycling. Finally, the exploitation of V has been increasing since the Industrial Revolution, and significant amounts of V have been released as a consequence into natural systems. Environmental concerns are promoting new areas of research to focus on V cycling between water, air, soil and sediment compartments. An increased understanding of V in all compartments, and knowledge of the processes that connect the compartments, is vital to tracing the fate of this intriguing element in natural systems.
Circadian rhythms of gene expression are generated by the combinatorial action of transcriptional and translational feedback loops as well as chromatin remodelling events. Recently, long noncoding ...RNAs (lncRNAs) that are natural antisense transcripts (NATs) to transcripts encoding central oscillator components were proposed as modulators of core clock function in mammals (Per) and fungi (frq/qrf). Although oscillating lncRNAs exist in plants, their functional characterization is at an initial stage.
By screening an Arabidopsis thaliana lncRNA custom-made array we identified CDF5 LONG NONCODING RNA (FLORE), a circadian-regulated lncRNA that is a NAT of CDF5. Quantitative real-time RT-PCR confirmed the circadian regulation of FLORE, whereas GUS- staining and flowering time evaluation were used to determine its biological function.
FLORE and CDF5 antiphasic expression reflects mutual inhibition in a similar way to frq/qrf. Moreover, whereas the CDF5 protein delays flowering by directly repressing FT transcription, FLORE promotes it by repressing several CDFs (CDF1, CDF3, CDF5) and increasing FT transcript levels, indicating both cis and trans function.
We propose that the CDF5/FLORE NAT pair constitutes an additional circadian regulatory module with conserved (mutual inhibition) and unique (function in trans) features, able to fine-tune its own circadian oscillation, and consequently, adjust the onset of flowering to favourable environmental conditions.
Purpose
Several studies have revealed that robot-assisted technique might improve the pedicle screw insertion accuracy, but owing to the limited sample sizes in the individual study reported up to ...now, whether or not robot-assisted technique is superior to conventional freehand technique is indefinite. Thus, we performed this systematic review and meta-analysis based on randomized controlled trials to assess which approach is better.
Methods
Electronic databases including PubMed, EMBASE, CENTRAL, ISI Web of Science, CNKI and WanFang were systematically searched to identify potentially eligible articles. Main endpoints containing the accuracy of pedicle screw implantation and proximal facet joint violation were evaluated as risk ratio (RR) and the associated 95% confidence intervals (95% CIs), while radiation exposure and surgical duration were presented as mean difference (MD) or standard mean difference (SMD). Meta-analyses were performed using RevMan 5.3 software.
Results
Six studies involving 158 patients (688 pedicle screws) in robot-assisted group and 148 patients (672 pedicle screws) in freehand group were identified matching our study. The Grade A accuracy rate in robot-assisted group was superior to freehand group (RR 1.03, 95% CI 1.00, 1.06;
P
= 0.04), but the Grade A + B accuracy rate did not differ between the two groups (RR 1.01, 95% CI 0.99, 1.02;
P
= 0.29). With regard to proximal facet joint violation, the combined results suggested that robot-assisted group was associated with significantly fewer proximal facet joint violation than freehand group (RR 0.07, 95% CI 0.01, 0.55;
P
= 0.01). As was the radiation exposure, our findings suggested that robot-assisted technique could significantly reduce the intraoperative radiation time (MD − 12.38, 95% CI − 17.95, − 6.80;
P
< 0.0001) and radiation dosage (SMD − 0.64, 95% CI − 0.85, − 0.43;
P
< 0.00001). But the overall surgical duration was longer in robot-assisted group than conventional freehand group (MD 20.53, 95% CI 5.17, 35.90;
P
= 0.009).
Conclusions
The robot-assisted technique was associated with equivalent accuracy rate of pedicle screw implantation, fewer proximal facet joint violation, less intraoperative radiation exposure but longer surgical duration than freehand technique. Powerful evidence relies on more randomized controlled trials with high quality and larger sample size in the future.
To improve our understanding of the carbon cycling response to imminent sea-level rise and saltwater intrusions, we review the existing literature on the likely effects of the increasing salinity and ...inundation on organic carbon mineralization in tidal wetlands. Enhanced salinity and inundation will reduce the pool of the organic carbon substrate, but may expand that of microbes with strong capacities for carbon metabolism. Sulfate availability increases with the increasing salinity, while availability of other electron acceptors, e.g., oxygen, nitrate, ferric oxides, and carbon dioxide, could transiently increase but would ultimately fall with the increasing salinity and inundation. The changing electron acceptor pattern may result in microbial sulfate reduction predominating over other carbon mineralization pathways. Data derived from natural salinity and inundation gradients suggest clear negative effects of salinity and inundation on production rates or emission fluxes of carbon dioxide and methane. However, results for brackish wetlands are conflicting, probably due to their unique geographic location. Salinity and inundation exert their influence on organic carbon mineralization through sulfate enrichment, elevating ionic and osmotic stress and decreasing oxygen concentrations and redox conditions, among other biogeochemical changes. Future studies should address the combined effects of salinity and inundation on carbon biogeochemistry in low-level salinity tidal wetlands.
Developing low‐cost, highly efficient, and durable electrocatalysts for oxygen evolution reaction (OER) is essential for the practical application of electrochemical water splitting. Herein, it is ...discovered that organic small molecule (hexabromobenzene, HBB) can activate commercial transition metal (Ni, Fe, and NiFe) foam by directly evolving metal nanomeshes embedded in graphene‐like films (M‐NM@G) through a facile Br‐induced solid‐phase migration process. Systematic investigations indicate that HBB can conformally generate graphene‐like network on bulk metal foam substrate via the cleavage of CBr bonds and the formation of CC linkage. Simultaneously, the cleaved CBr fragments can efficiently extract metal atoms from bulk substrate, in situ producing transition metal nanomeshes embedded in the graphene‐like films. As a result, such functional nanostructure can serve as an efficient OER electrocatalyst with a low overpotential and excellent long‐term stability. Specifically, the overpotential at 100 mA cm−2 is only 208 mV for NiFe‐NM@G, ranking the top‐tier OER electrocatalysts. This work demonstrates an intriguing general strategy for directly transforming bulk transition metals into nanostructured functional electrocatalysts via the interaction with organic small molecules, opening up opportunities for bridging the application of organic small molecules in energy technologies.
Transition metal nanomeshes embedded in graphene‐like film (M‐NM@G) are achieved via a newly developed Br‐induced solid‐phase migration method enabled by directly treating commercial transition metal foam with organic small molecules. NiFe‐NM@G exhibits excellent oxygen evolution reaction performance with a low overpotential of 208 mV at a current density of 100 mA cm−2, as well as excellent long‐term stability.
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