BackgroundHumans often show impatience when making intertemporal choice for monetary rewards, preferring small rewards delivered immediately to larger rewards delivered after a delay, which reflects a fundamental psychological principle: delay discounting. However, we propose that episodic prospection humans can vividly envisage exerts a strong and broad influence on individuals' delay discounting. Specifically, episodic prospection may affect individuals' intertemporal choice by the negative or positive emotion of prospection.Methodology/Principal FindingsThe present study explored how episodic prospection modulated delay discounting by emotion. Study 1 showed that participants were more inclined to choose the delayed but larger rewards when they imaged positive future events than when they did not image events; Study 2 showed that participants were more inclined to choose the immediate but smaller rewards when they imaged negative future events than when they did not image events; In contrast, study 3 showed that choice preferences of participants when they imaged neutral future events were the same as when they did not image events.Conclusions/SignificanceBy manipulating the emotion valence of episodic prospection, our findings suggested that positive emotion made individuals tend to choose delayed rewards, while negative emotion made individuals tend to choose immediate rewards. Only imaging events with neutral emotion did not affect individuals' choice preference. Thus, the valence of imaged future events' emotion might play an important role in individuals' intertemporal choice. It is possible that the valence of emotion may affect the changed direction (promote or inhibit) of individuals' delay discounting, while the ability to image future events affects the changed degree of individuals' delay discounting.

Although many efforts have been devoted to the adsorptive removal of phosphate from aqueous solutions and eutrophic water, it is still highly desirable to develop novel adsorbents with high adsorption capacities. In this study, Fe-based metal-organic frameworks (MOFs), MIL-101 and NH2-MIL-101, are fabricated through a general facile strategy. Their performance as an adsorbent for phosphate removal is investigated. Experiments are performed to study the effects of various factors on the phosphate adsorption, including adsorbent dosage, contact time and co-existing ions. Both MIL-101(Fe) and NH2-MIL-101(Fe) show highly effective removal of phosphates from aqueous solutions, and the concentration of phosphates decrease sharply from the initial 0.60 mg·L−1 to 0.045 and 0.032 mg·L−1, respectively, within just 30 min of exposure. The adsorption kinetics and adsorption isotherms reveal that NH2-MIL-101(Fe) has higher adsorption capacity than MIL-101(Fe) possibly due to the amine group. Furthermore, the Fe-based MOFs also exhibit a high selectivity towards phosphate over other anions such as chloride, bromide, nitrate and sulfate. Particularly, the prepared Fe-based MIL-101 materials are also capable of adsorbing phosphate in an actual eutrophic water sample and display better removal effect.

LuxR transcriptional regulator is a key player in Quorum Sensing (QS), coordinates the expression of a variety of genes, including those encoding virulence factors and antibiotics biosynthesis, motility, nodulation, plasmid transfer, bioluminescence, and biofilm formation. The characteristics and roles of this family, especially those of Mycobacterium, are summarized in this paper to give clues for drug target discovery.

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Porous hierarchical architectures of few-layer MoS2 nanosheets dispersed in carbon matrix are prepared by a microwave-hydrothermal method followed by annealing treatment via using glucose as C source and structure-directing agent and (NH4 )2 MoS4 as both Mo and S sources. It is found that the morphology and size of the secondary building units (SBUs), the size and layer number of MoS2 nanosheets as well as the distribution of MoS2 nanosheets in carbon matrix, can be effectively controlled by simply adjusting the molar ratio of (NH4 )2 MoS4 to glucose, leading to the materials with a low charge-transfer resistance, many electrochemical active sites and a robust structure for an outstanding energy storage performance including a high specific capacitance (589 F g(-1) at 0.5 A g(-1) ), a good rate capability (364 F g(-1) at 20 A g(-1) ), and an excellent cycling stability (retention 104% after 2000 cycles) for application in supercapacitors. The exceptional rate capability endows the electrode with a high energy density of 72.7 Wh kg(-1) and a high power density of 12.0 kW kg(-1) simultaneously. This work presents a facile and scalable approach for synthesizing novel heterostructures of MoS2 -based electrode materials with an enhanced rate capability and cyclability for potential application in supercapacitor.

The states and structure of the solubilized water in reversed micelles and microemulsions of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) and of sodium bis(2-ethylhexyl) phosphate (NaDEHP) in n-heptane have been characterized by FT-IR and NMR spectroscopic parameters. According to the four-component hydration model, the free, anion-bound, bulklike, and cation-bound water are present in reversed micelles and both of the water-in-oil (W/O) microemulsions formed by AOT and the bicontinuous microemulsions formed by NaDEHP in n-heptane. The observed chemical shifts (δ) of the water protons from NMR spectra were expressed as the weighted average of the in-core anion-bound, bulklike, and cation-bound water. Chemical shifts δ for individual components were evaluated from molar fractions, which were obtained by deconvolution of the O−H stretching vibrational absorption bands, and the observed δ. Results show that in W/O microemulsion of AOT in n-heptane and bicontinuous microemulsion of NaDEHP in n-heptane, the chemical shifts for individual components exhibit constant values, indicating stable microstructure for the given species, which can be considered as the criterion of either W/O or bicontinuous microemulsions. Results also show that in reversed micelles of both AOT and NaDEHP, the O−H bond strength and thereby the microstructure of different hydration species vary with water content, which can be explained by the interaction between electrical double layers. In transition of reversed micelles to microemulsions, the microstructures of water molecules transform from the variable state to a stable state.

In this paper, a quasistatic model is extended to describe the double ionization of Helium in intense linearly polarized field, yielding achieve an insight to the two-electron correlation effect in the ionization dynamics. Our numerical calculations reproduce the excessive double ionization and the photoelectron spectra observed experimentally both quantitatively and qualitatively. Moreover, it is shown that the classical collisional trajectories are the main source of the double ionization in the knee regime and responsible for the unusual angular distribution of the photoelectrons.PACS numbers: 32.80. Rm, 42.50.Hz, Recently the excessive double ionization observed in Helium experiments by Fittinghoff et al. [1], Walker et al.[2], and Sheehy et al. [3] draws much attention to the multiple-electron dynamics in the laser-atom interaction. In these experiments the single ionization yields of He in a linearly polarized field is accurately predicted by the single active electron (SAE) approximation [2], well described by the Ammosov-Delone-Krainov (ADK) tunneling theory [4]. However, the case of double ionization is more complicated. In the regime of very high intensities (I > 10 16 W/cm 2 ) where strong double ionization occurs, the double ionization keeps in good agreement with the sequential SAE models as that in the lower intensities regime(I < 10 14 W/cm 2 ). The double ionization yield deviates seriously from the sequential SAE model and shows a great enhancement in a "knee" regime [(0.8-3.0) × 10 15 W/cm 2 ], where the He 2+ /He + yields ratio is close to a constant: 0.002. This surprising large yields of the double ionization obviously indicates that the sequential ionization is no longer the dominating process in this regime and the electron-electron correlation has to be taken into account.Both the "shake-off" model and the "recollision" model are suggested to describe the electron's correlation [1,3,5,6]. However, none of the two nonsequential ionization (NSI) mechanisms can completely explain the experimental observations. For the "shake-off" model, it can not give the reason for the decrease in the double ionization yields as the polarization of the laser field departs from linear [7][8][9]. In the "recollision" model, the returning electrons are known to have a maximum classical kinetic energy of ∼ 3.2U p (U p = e 2 F 2 /4m e ω 2 ), so one can determine a minimum intensity required for the rescattering electron to have enough energy to excite the inner electron. But the double ionization yields observed in experiments have no such an intensity threshold. In fact, the double ionization process is rather complicated and subtle, both of the two NSI processes and the sequential ionization contribute to the double ionization yields and may dominate in the different regimes.The experiments on the double ionization of Helium are mainly confined in the tunneling regime, i.e. the ratio between the tunneling time of the outer electron and the inverse optical frequency (Keldysh parameter) is less than 1. ...

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