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The conversion of inorganic mercury (Hg(II)) to methylmercury (MeHg) is central to the understanding of Hg toxicity in the environment. Hg methylation occurs in the cytosol of certain obligate anaerobic bacteria and archaea possessing the hgcAB gene cluster. However, the processes involved in Hg(II) biouptake and methylation are not well understood. Here, we examined the role of cell surface thiols, cellular ligands with the highest affinity for Hg(II) that are located at the interface between the outer membrane and external medium, on the sorption and methylation of Hg(II) by Geobacter sulfurreducens. The effect of added cysteine (Cys), which is known to greatly enhance Hg(II) biouptake and methylation, was also explored. By quantitatively blocking surface thiols with a thiol binding ligand (qBBr), we show that surface thiols have no significant effect on Hg(II) methylation, regardless of Cys addition. The results also identify a significant amount of cell-associated Hg-S3/S4 species, as studied by high energy-resolution X-ray absorption near edge structure (HR-XANES) spectroscopy, under conditions of high MeHg production (with Cys addition). In contrast, Hg-S2 are the predominant species during low MeHg production. Hg-S3/S4 species may be related to enhanced Hg(II) biouptake or the ability of Hg(II) to become methylated by HgcAB and should be further explored in this context.Thermoelectric (TE) materials are important for sustainable development because they can directly convert heat into electricity. Compared with inorganic TE materials, conductive polymers have demonstrated unique benefits and their irreplaceability. But their TE properties, particularly the Seebeck coefficient, must be greatly enhanced for practical application. In this work, MXene (Ti3C2Tx), an n-type two-dimensional material, is blended into p-type poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate) (PEDOTPSS). The Seebeck coefficient of the composites increases with the increasing MXene loading at the MXene loading below 33 wt % and then decreases with further increasing of the MXene loading. MXene can enhance the Seebeck coefficient from 23 up to 57.3 μV K-1 and the power factor from 44.1 up to 155 μW m-1 K-2. For the first time, enhancement in the Seebeck coefficient of a p-type TE polymer by an n-type filler has been achieved. Enhancement in the Seebeck coefficient is ascribed to energy filtering of charge carriers by the internal electric field arising from the electron transfer from MXene to PEDOTPSS. The internal electric field can filter the charge carriers with low energy and thus enhance the Seebeck coefficient.Quantum states are described by wave functions whose phases cannot be directly measured but which play a vital role in quantum effects such as interference and entanglement. The loss of the relative phase information, termed decoherence, arises from the interactions between a quantum system and its environment. Decoherence is perhaps the biggest obstacle on the path to reliable quantum computing. Here we show that decoherence occurs even in an isolated molecule, although not all phase information is lost, via a theoretical study of a central electron spin qubit interacting with nearby nuclear spins in prototypical magnetic molecules. The residual coherence, which is molecule-dependent, provides a microscopic rationalization for the nuclear spin diffusion barrier proposed to explain experiments. The contribution of nearby molecules to the decoherence has a nontrivial dependence on separation, peaking at intermediate distances. Molecules that are far away affect only the long-time behavior. Because the residual coherence is simple to calculate and correlates well with the coherence time, it can be used as a descriptor for coherence in magnetic molecules. This work will help establish design principles for enhancing coherence in molecular spin qubits and serve to motivate further theoretical work.We present here two irreversible Markov chain Monte Carlo algorithms for general discrete state systems. One of the algorithms is based on the random-scan Gibbs sampler for discrete states and the other on its improved version, the Metropolized-Gibbs sampler. The algorithms we present incorporate the lifting framework with skewed detailed balance condition and construct irreversible Markov chains that satisfy the balance condition. We have applied our algorithms to 1D 4-state Potts model. The integrated autocorrelation times for magnetization and energy density indicate a reduction of the dynamical scaling exponent from z ≈ 1 to z ≈ 1/2. In addition, we have generalized an irreversible Metropolis-Hastings algorithm with skewed detailed balance, initially introduced by Turitsyn et al. [ Physica D 2011, 240, 410] for the mean field Ising model, to be now readily applicable to classical spin systems in general; application to 1D 4-state Potts model indicate a square root reduction of the mixing time at high temperatures.OBJECTIVE Insomnia is a risk factor for suicide, and the risk of suicide after accounting for population wakefulness is disproportionately highest at night. This study investigated whether this risk varied across months and/or methods of suicide. METHODS Time, date, method (eg, firearm, poisoning), and demographic information for 35,338 suicides were collected from the National Violent Death Reporting System for the years 2003-2010. Time of fatal injury was grouped into 1-hour bins and compared to the estimated hourly proportion of the population awake from the American Time Use Survey for 2003-2010. Negative binomial modeling then generated hourly incidence risk ratios (IRRs) of suicide. Risks were then aggregated into 4 categories morning (600 am to 1159 am), afternoon (noon to 559 pm), evening (600 pm to 1159 pm), and night (midnight to 559 am). RESULTS The risk of suicide was higher at night across all months (P .05). selleck products CONCLUSIONS Regardless of month or method, the incidence risk of suicide at night is higher than at any other time of day. Additionally, demographic subgroups did not differentially experience higher risks across months or mechanisms at night. © Copyright 2020 Physicians Postgraduate Press, Inc.