Two-dimensional atomic crystals, such as two-dimensional oxides, have attracted much attention in energy storage because nearly all of the atoms can be exposed to the electrolyte and involved in ...redox reactions. However, current strategies are largely limited to intrinsically layered compounds. Here we report a general strategy that uses the surfaces of water-soluble salt crystals as growth templates and is applicable to not only layered compounds but also various transition metal oxides, such as hexagonal-MoO3, MoO2, MnO and hexagonal-WO3. The planar growth is hypothesized to occur via a match between the crystal lattices of the salt and the growing oxide. Restacked two-dimensional hexagonal-MoO3 exhibits high pseudocapacitive performances (for example, 300 F cm(-3) in an Al2(SO4)3 electrolyte). The synthesis of various two-dimensional transition metal oxides and the demonstration of high capacitance are expected to enable fundamental studies of dimensionality effects on their properties and facilitate their use in energy storage and other applications.
Diatoms, one of the most important phytoplankton groups, fulfill their carbon demand from seawater mainly by obtaining passively diffused carbon dioxide (CO
2
) and/or actively consuming ...intracellular energy to acquire bicarbonate (HCO
3
–
). An anthropogenically induced increase in seawater CO
2
reduces the HCO
3
–
requirement of diatoms, potentially saving intracellular energy and benefitting their growth. This effect is commonly speculated to be most remarkable in larger diatoms that are subject to a stronger limitation of CO
2
supply because of their smaller surface-to-volume ratios. However, we constructed a theoretical model for diatoms and revealed a unimodal relationship between the simulated growth rate response (GRR, the ratio of growth rates under elevated and ambient CO
2
) and cell size, with the GRR peaking at a cell diameter of ∼7 μm. The simulated GRR of the smallest diatoms was low because the CO
2
supply was nearly sufficient at the ambient level, while the decline of GRR from a cell diameter of 7 μm was simulated because the contribution of seawater CO
2
to the total carbon demand greatly decreased and diatoms became less sensitive to CO
2
increase. A collection of historical data in CO
2
enrichment experiments of diatoms also showed a roughly unimodal relationship between maximal GRR and cell size. Our model further revealed that the “optimal” cell size corresponding to peak GRR enlarged with the magnitude of CO
2
increase but diminished with elevating cellular carbon demand, leading to projection of the smallest optimal cell size in the equatorial Pacific upwelling zone. Last, we need to emphasize that the size-dependent effects of increasing CO
2
on diatoms are multifaceted, while our model only considers the inorganic carbon supply from seawater and optimal allocation of intracellular energy. Our study proposes a competitive advantage of middle-sized diatoms and can be useful in projecting changes in the diatom community in the future acidified high-CO
2
ocean.
•Juniperus tibetica and Abies spectabilis trees showed different resilience to drought extremes in the past two hundred years.•Trees’ iso/anisohydric strategies of stomatal regulation might play a ...role in their resilience against droughts.•Abies spectabilis showed higher resistance than Juniperus tibetica in the twentieth century.
With increased frequency and intensity of drought occurrence in the changing climate, the drought resilience of forest trees is of widespread interest. Particularly, it is not clear as to how the resilience differs between tree species and whether or not such resilience changes over time. Understanding tree resilience to drought requires observations not only from recent events but also from the historical past, information of which is usually hardly available. Here we defined historical drought based on isotope data and compared drought resilience in Juniperus tibetica and Abies spectabilis forest in the central Himalayas in five extreme droughts during the past two centuries. We found that juniper trees had a stronger resistance than fir trees in the three extreme droughts in the nineteenth century but this pattern reversed in the two drought events in the twentieth century. The length of response time to droughts and recovery time to pre-drought state were shorter in juniper trees than in fir trees. The proportion of declining trees showed a decreasing trend in fir trees but not in juniper trees. Our results indicate that the species-specific resilience might be related to the anisohydric (junipers) and isohydric (firs) strategies of stomatal regulation in response to droughts plants. The differences in species-specific drought resilience should be taken into account when developing forest management policies against the influence of extreme droughts in future.
Nano drug-delivery systems (DDS) may significantly improve efficiency and reduce toxicity of loaded drugs, but a few nano-DDS are highly successful in clinical use. Unprotected nanoparticles in blood ...flow are often quickly cleared, which could limit their circulation time and drug delivery efficiency. Elongating their blood circulation time may improve their delivery efficiency or grant them new therapeutic possibilities. Erythrocytes are abundant endogenous cells in blood and are continuously renewed, with a long life span of 100-120 days. Hence, loading nanoparticles on the surface of erythrocytes to protect the nanoparticles could be highly effective for enhancing their in vivo circulation time. One of the key questions here is how to properly attach nanoparticles on erythrocytes for different purposes and different types of nanoparticles to achieve ideal results. In this review, we describe various methods to attach nanoparticles and drugs to the erythrocyte surface, and discuss the key factors that influence the stability and circulation properties of the erythrocytes-based delivery system in vivo. These data show that using erythrocytes as a host for nanoparticles possesses great potential for further development.
Recently, the residues of quinolones have received widespread attention. However, toxicological studies on aquatic organisms are relatively scarce, especially on the liver metabolism and immune ...effects of these aquatic organisms. In this study, we investigated the toxic effects of carp exposed to 0, 100 ng/L, and 1 mg/L norfloxacin (NOR) at environmental concentrations for 42 days. In this study, through transcriptomics analysis, we found that some genes involved in lipid metabolism, immune response, and cytochrome P450 metabolism, especially genes accounting for the metabolism-related disorders of glucose and lipid. Defects in these genes and thus their related pathways increase the risk of coming down with nonalcoholic fatty liver disease. Compared to those of the control, results from the biochemical indicators of the treatment group changed significantly, including levels of total cholesterol, triglycerides, glucose, and insulin. Moreover, our results confirmed that NOR at environmental concentrations disordered the metabolism of glucose and lipid in the carp also resulted in hepatocellular and nuclear enlargement. Our results, therefore, confirmed that long-term exposure to NOR can induce carp liver toxicity at histological, biochemical, and transcriptional levels and provided the latest data and theoretical basis for the toxicology study of quinolones in the natural environment.
•Sub-chronic NOR exposure led to disorders of metabolism lipid and glucose in carp.•Sub-chronic NOR exposure resulted in significant changes in biochemical parameters in carp.•Sub-chronic NOR exposure induced histological damage in carp liver.
Network based medical data computing and collaborative visualization have been commonly used in remote medicine and distributed diagnosis, where visualizing 3D medical data on web browsers and ...sharing medical information on internet are critically important. However, due to the lack of efficient algorithms and compatible graphics hardware support, there are still some major technical challenges in web based medical data visualization and information exploration on internet. To address these practical issues, we created a new network based medical data rendering and information sharing system, where an Apache HTTP Server was applied to handle data information, and MySQL and PHP were exploited for data storage and management. In this system, medical data rendering and computation were supported with GPU and WebGL 2.0 (WebGL2), and a novel data information extraction algorithm was designed to optimize data storage and management. Taking advantage of the new 3D features of WebGL2, a web based raycasting algorithm was developed to deliver real-time data visualization on web browsers, in which a novel voxel classification method was integrated for color mapping and high-quality image generation.
The developed medical information system can deliver 60 ± 2 frames per second rendering performance for high-quality medical data visual exploration on modern browsers as well as medical information communication on internet. The system has been seamlessly integrated with web server, database and client computers equipped with modern graphics hardware, which has wide applications in the fields such as internet based computer-aided medical decision and education, as well as distributed disease diagnosis.
Considering simultaneous wireless information and power transfer (SWIPT), we investigate cooperative-jamming (CJ) aided robust secure transmission design in multiple-input-single-output channels, ...where a cooperative jammer introduces jamming interferences and assists a source to supply wireless power for both an energy receiver and a legitimate destination. The destination employs a power splitting (PS) scheme to split the received signals for both information decoding and energy harvesting (EH). Compared with conventional transmission without SWIPT, the transmission with SWIPT should satisfy additional worst-case EH constraints. Furthermore, the PS scheme introduces an additional multiplicative optimization variable, i.e., the PS factor. Our objective is to maximize worst-case secrecy rate under transmit power constraints and worst-case EH constraints. We propose to decouple the problem into three optimization problems and employ alternating optimization algorithm to obtain the locally optimal solution. For the optimization of transmit covariance matrices and PS factor, we propose to employ the S-procedure and its extension to reformulate it as a convex semidefinite programming. It is shown through the simulation results that our proposed CJ aided robust secure transmission scheme outperforms the robust direct transmission scheme without CJ and the CJ aided non-robust scheme.
Summary
It has been widely reported that probiotic consortia in the rhizosphere can enhance the plant resistance to pathogens. However, the general composition and functional profiles of bacterial ...community in soils which suppress multiple diseases for various plants remain largely unknown. Here, we combined metadata analysis with machine learning to identify the general patterns of bacterial‐community composition in disease‐suppressive soils. Disease‐suppressive soils significantly enriched Firmicutes and Actinobacteria but showed a decrease in Proteobacteria and Bacteroidetes. Our machine‐learning models accurately identified the disease‐conducive and ‐suppressive soils with 54 biomarker genera, 28 of which were potentially beneficial. We further carried out a successive passaging experiment with the susceptible rps2 mutant of Arabidopsis thaliana invaded by Pseudomonas syringae pv. tomato DC3000 (avrRpt2) for functional verification of potential beneficial bacteria. The disease‐suppressive ability of Kribbella, Nocardioides and Bacillus was confirmed, and they positively activated the pathogen‐associated molecular patterns‐triggered immunity pathway. Results also showed that chemical control by pesticides in agricultural production decreased the disease‐suppressive ability of soil. This study provides a method for accurately predicting the occurrence of multiple diseases in soil and identified potential beneficial bacteria to guide a wide range of multiple‐strain biological control strategies in agricultural management.
A
bstract
It is well known that forward limits of tree-level amplitudes (and those trivalent diagrams they consist of) produce one-loop amplitudes and trivalent diagrams with propagators linear in ...the loop momentum. They naturally arise from one-loop worldsheet formulae, and an important open problem is how to recombine them into usual one-loop diagrams with quadratic propagators. In this paper, we study a new collection of worldsheet functions: generalized one-loop Parke-Taylor factors with tensor numerators, which are conjectured to serve as a basis for one-loop worldsheet functions with this nice property. We present all-multiplicity, closed-form expressions for combinations of one-loop trivalent diagrams with quadratic propagators and tensor numerators to arbitrary rank (including possible tadpole contributions), produced by any pair of Parke-Taylor factors. We also briefly comment on reducing worldsheet functions onto such a basis, and applications to one-loop amplitudes in physical theories.
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