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It has been shown recently that the overpotential originating from ionic conduction of alkali-ions through the inner dense solid-electrolyte interphase (SEI) is strongly non-linear. An empirical equation was proposed to merge the measured resistances from both galvanostatic cycling (GS) and electrochemical impedance spectroscopy (EIS) at 25$^{\circ}$C. Here, this analysis is extended to the full temperature range of batteries from -40$^{\circ}$C to +80$^{\circ}$C for Li, Na, K and Rb-metal electrodes in carbonate electrolytes. Two different transport mechanisms are found. The first one conducts alkali-ions at all measured temperatures. The second transport mechanism conducts ions for all seven measured Li-ion electrolytes and one out of four Na-ion electrolytes, however, only above a certain critical temperature $T_C$. At $T_C$ a phase transition is observed switching-off the more efficient transport mechanism and leaving only the general ion conduction mechanism. The associated overpotentials increase rapidly below $T_C$ depending on alkali-ion, salt and solvent and become a limiting factor during galvanostatic operation of all Li-ion electrolytes at low temperature. In general, the current analysis merges the SEI resistances measured by EIS ranging from 26 $\Omega$cm$^2$ for the best Li up to 292 M$\Omega$cm$^2$ for Rb electrodes to its galvanostatic response over seven orders of magnitude. The determined critical temperatures are between 0-25$^{\circ}$C for the tested Li and above 50$^{\circ}$C for Na electrolytes., Comment: 10 pages, 7 figures, file includes Suppl Info, http://jes.ecsdl.org/content/165/2/A323

In today's modeling and analysis of electrochemical cycling of Li- and Na-ion batteries, an assumption is often made regarding the interphase that forms between the active material and liquid electrolyte at low potentials, the so-called solid-electrolyte interphase (SEI). The SEI is generally assumed to act like an Ohmic resistor despite its complex chemical composition and porosity distribution. Here, one reports that this assumption does not hold for alkali-ion batteries. The SEI possesses a non-linear overpotential characteristic which saturates already at low current density of 0.1 mAcm-2 giving only 3.3$\pm$1 mV for Li-metal electrodes in different electrolytes. For Na- and K-metal electrodes, these SEI overpotentials become dominating with 31 mV and 72 mV at the same low current densities giving significant disadvantages over Li-ion batteries for commercial applications. With the introduction of a new term, one achieves agreement between the parameters from galvanostatic cycling and electrochemical impedance spectroscopy for the first time. The discovery of the non-linear SEI overpotential disrupts the general believes about the role of the SEI for today's batteries as it is basically negligible for Li-ion batteries at room temperature., Comment: 7 pages, 4 figures, 1x Suppl Info with 25pages

Donor T cell mediated graft vs. host effects may result from the aggregate alloreactivity to minor histocompatibility antigens (mHA) presented by the HLA in each donor-recipient pair (DRP) undergoing stem cell transplantation (SCT). Whole exome sequencing has demonstrated extensive nucleotide sequence variation in HLA-matched DRP. Non-synonymous single nucleotide polymorphisms (nsSNPs) in the GVH direction (polymorphisms present in recipient and absent in donor) were identified in 4 HLA-matched related and 5 unrelated DRP. The nucleotide sequence flanking each SNP was obtained utilizing the ANNOVAR software package. All possible nonameric-peptides encoded by the non-synonymous SNP were then interrogated in-silico for their likelihood to be presented by the HLA class I molecules in individual DRP, using the Immune-Epitope Database (IEDB) SMM algorithm. The IEDB-SMM algorithm predicted a median 18,396 peptides/DRP which bound HLA with an IC50 of <500nM, and 2254 peptides/DRP with an IC50 of <50nM. Unrelated donors generally had higher numbers of peptides presented by the HLA. A similarly large library of presented peptides was identified when the data was interrogated using the Net MHCPan algorithm. These peptides were uniformly distributed in the various organ systems. The bioinformatic algorithm presented here demonstrates that there may be a high level of minor histocompatibility antigen variation in HLA-matched individuals, constituting an HLA-specific alloreactivity potential. These data provide a possible explanation for how relatively minor adjustments in GVHD prophylaxis yield relatively similar outcomes in HLA matched and mismatched SCT recipients., Comment: Abstract: 235, Words: 6422, Figures: 7, Tables: 3, Supplementary figures: 2, Supplementary tables: 2

The kinetic performance of graphite particles is difficult to deconvolute from half-cell experiments, where the influences of the working electrode porosity and the counter electrode contribute nonlinearly to the electrochemical re-sponse. Therefore, thin-layer electrodes of circa 1 {\mu}m thickness were prepared with standard, highly crystalline graphite particles to evaluate their rate capability. The performance was evaluated based on the different stage transitions. We found that the tran-sitions towards the dense stages 1 and 2 with LiC6 in-plane densi-ty are one of the main rate limitations for charge and discharge. But surprisingly, the transitions towards the dilute stages 2L, 3L, 4L, and 1L progress very fast and can even compensate for the initial diffusion limitations of the dense stage transitions during discharge. We show the existence of a substantial difference between the diffusion coefficients of the liquid-like stages and the dense stages. We also demonstrate that graphite can be charged at a rate of ~6C (10 min) and discharged at 600C (6 s) while maintaining 80 % of the total specific charge for particles of 3.3 {\mu}m median diameter. Based on these findings, we propose a shrinking annuli mechanism which describes the propagation of the different stages in the particle at medium and high rates. Besides the limited applicable overpotential during charge, this mechanism can explain the long-known but as yet unexplained asymmetry between the charge and discharge rate performance of lithium intercalation in graphite., Comment: 10 pages, 13 Figures, supplementary information

This paper reports on the scalability of the answer extraction system ExtrAns. An answer extraction system locates the exact phrases in the documents that contain the explicit answers to the user queries. Answer extraction systems are therefore more convenient than document retrieval systems in situations where the user wants to find specific information in limited time. ExtrAns performs answer extraction over UNIX manpages. It has been constructed by combining available linguistic resources and implementing only a few modules from scratch. A resolution procedure between the minimal logical form of the user query and the minimal logical forms of the manpage sentences finds the answers to the queries. These answers are displayed to the user, together with pointers to the respective manpages, and the exact phrases that contribute to the answer are highlighted. This paper shows that the increase in response times is not a big issue when scaling the system up from 30 to 500 documents, and that the response times for 500 documents are still acceptable for a real-time answer extraction system., Comment: 5 pages

A system is described that uses a mixed-level knowledge representation based on standard Horn Clause Logic to represent (part of) the meaning of natural language documents. A variable-depth search strategy is outlined that distinguishes between the different levels of abstraction in the knowledge representation to locate specific passages in the documents. A detailed description of the linguistic aspects of the system is given. Mixed-level representations as well as variable-depth search strategies are applicable in fields outside that of NLP., Comment: 29 pages

A system is described that uses a mixed-level representation of (part of) meaning of natural language documents (based on standard Horn Clause Logic) and a variable-depth search strategy that distinguishes between the different levels of abstraction in the knowledge representation to locate specific passages in the documents. Mixed-level representations as well as variable-depth search strategies are applicable in fields outside that of NLP., Comment: 8 pages, Proceedings of the Eighth International Conference on Tools with Artificial Intelligence (TAI'96), Los Alamitos CA