Comparing and contrasting Escherichia coli and Mycobacterium tuberculosis mechanosensitive channels (MscL) - New gain of function mutations in the loop region

Sequence analysis of 35 putative MscL homologues was used to develop an optimal alignment for Escherichia coli and Mycobacterium tuberculosis MscL and to place these homologues into sequence subfamilies. By using this alignment, previously identified E. coli MscL mutants that displayed severe and very severe gain of function phenotypes were mapped onto the M. tuberculosis MscL sequence. Not all of the resulting M. tuberculosis mutants displayed a gain of function phenotype; for instance, normal phenotypes were noted for mutations at Ala20, the analogue of the highly sensitive Gly22 site in E. coli. A previously unnoticed intersubunit hydrogen bond in the extracellular loop region of the M. tuberculosis MscL crystal structure has been analyzed. Cross-linkable residues were substituted for the residues involved in the hydrogen bond, and cross-linking studies indicated that these sites are spatially close under physiological conditions. In general, mutation at these positions results in a gain of function phenotype, which provides strong evidence for the importance of the loop region in MscL channel function. No analogue to this interesting interaction could be found in E. coli MscL by sequence alignment. Taken together, these results indicate that caution should be exercised in using the M. tuberculosis MscL crystal structure to analyze previous functional studies of E. coli MscL

A reversible theory of entanglement and its relation to the second law

We consider the manipulation of multipartite entangled states in the limit of many copies under quantum operations that asymptotically cannot generate entanglement. As announced in [Brandao and Plenio, Nature Physics 4, 8 (2008)], and in stark contrast to the manipulation of entanglement under local operations and classical communication, the entanglement shared by two or more parties can be reversibly interconverted in this setting. The unique entanglement measure is identified as the regularized relative entropy of entanglement, which is shown to be equal to a regularized and smoothed version of the logarithmic robustness of entanglement. Here we give a rigorous proof of this result, which is fundamentally based on a certain recent extension of quantum Stein's Lemma proved in [Brandao and Plenio, Commun. Math. 295, 791 (2010)], giving the best measurement strategy for discriminating several copies of an entangled state from an arbitrary sequence of non-entangled states, with an optimal distinguishability rate equal to the regularized relative entropy of entanglement. We moreover analyse the connection of our approach to axiomatic formulations of the second law of thermodynamics.Comment: 21 pages. revised versio

Technical Review Panel for the Pension Insurance Modeling System (PIMS)

In April of 2013, the Pension Research Council of the Wharton School at the University of Pennsylvania convened a Technical Review Panel, comprising ten experts whose task it was to review the Pension Benefit Guaranty Corporation’s (PBGC) Pension Insurance Modeling System (PIMS), including inputs, outputs, and model assumptions. The review was intended to provide a formal evaluation of the technical adequacy of the model by outside experts. Each expert participating on the Technical Panel was asked to review background material (see References) and focus on a particular aspect of the PIMS model. The list of panelists and topics was developed by the Council in discussion with the Social Security Administration (SSA). This report and the appended papers herein from our Technical Panel comprise the Final Report under this project. The Panel’s key findings may be summarized as follows: (1) The PIMS models are an important and valuable tool in modeling the Agency’s liability risk. To the best of our knowledge, there is no other model that can do a comparable job. (2) Nevertheless, some improvements could be integrated in the Agency’s approach to modeling. Those deserving highest priority attention in the experts’ view are the following: (a) Incorporating systematic mortality risk (i.e., treat mortality and longevity as stochastic variables); (b) Including new asset classes increasingly found in defined benefit plan portfolios (e.g., commercial real estate, private equity funds, infrastructure, hedge funds, and others); (c) Developing a more complex model for the term structure of interest rates; and (d) Incorporating an option value approach to pricing the insurance provided. (3) The Agency could also do more to communicate the range of uncertainty and potential for problems associated with the PBGC’s financial status. This could include additional information including the Conditional Value at Risk (CVaR), and perhaps an ‘intermediate,’ ‘optimistic,’ and ‘pessimistic’ set of projected outcomes, as well as the expected ‘date of exhaustion’ for assets backing pension benefits insured by the PBGC.Social Security Administrationhttp://deepblue.lib.umich.edu/bitstream/2027.42/102265/1/wp290.pd

The prevalence, characteristics and effectiveness of Aichi Target 11 ' s "other effective area-based conservation measures" (OECMs) in Key Biodiversity Areas

Aichi Target 11 of the CBD Strategic Plan for Biodiversity commits countries to the effective conservation of areas of importance for biodiversity, through protected areas and “other effective area-based conservation measures” (OECMs). However, the prevalence and characteristics of OECMs are poorly known, particularly in sites of importance for biodiversity. We assess the prevalence of potential OECMs in 740 terrestrial Key Biodiversity Areas (KBAs) outside known or mapped protected areas across ten countries. A majority of unprotected KBAs (76.5%) were at least partly covered by one or more potential OECMs. The conservation of ecosystem services or biodiversity was a stated management aim in 73% of these OECMs. Local or central government bodies managed the highest number of potential OECMs, followed by local and indigenous communities and private landowners. There was no difference between unprotected KBAs with or without OECMs in forest loss or in a number of state-pressure-response metrics.The project was funded by the CCI Collaborative Fun

Faithful Squashed Entanglement

Squashed entanglement is a measure for the entanglement of bipartite quantum states. In this paper we present a lower bound for squashed entanglement in terms of a distance to the set of separable states. This implies that squashed entanglement is faithful, that is, strictly positive if and only if the state is entangled. We derive the bound on squashed entanglement from a bound on quantum conditional mutual information, which is used to define squashed entanglement and corresponds to the amount by which strong subadditivity of von Neumann entropy fails to be saturated. Our result therefore sheds light on the structure of states that almost satisfy strong subadditivity with equality. The proof is based on two recent results from quantum information theory: the operational interpretation of the quantum mutual information as the optimal rate for state redistribution and the interpretation of the regularised relative entropy of entanglement as an error exponent in hypothesis testing. The distance to the set of separable states is measured by the one-way LOCC norm, an operationally-motivated norm giving the optimal probability of distinguishing two bipartite quantum states, each shared by two parties, using any protocol formed by local quantum operations and one-directional classical communication between the parties. A similar result for the Frobenius or Euclidean norm follows immediately. The result has two applications in complexity theory. The first is a quasipolynomial-time algorithm solving the weak membership problem for the set of separable states in one-way LOCC or Euclidean norm. The second concerns quantum Merlin-Arthur games. Here we show that multiple provers are not more powerful than a single prover when the verifier is restricted to one-way LOCC operations thereby providing a new characterisation of the complexity class QMA.Comment: 24 pages, 1 figure, 1 table. Due to an error in the published version, claims have been weakened from the LOCC norm to the one-way LOCC nor

The prevalence, characteristics and effectiveness of Aichi Target 11's "other effective area‐based conservation measures" (OECMs) in key biodiversity areas

Aichi Target 11 of the CBD Strategic Plan for Biodiversity commits countries to the effective conservation of areas of importance for biodiversity, through protected areas and "other effective area-based conservation measures" (OECMs). However, the prevalence and characteristics of OECMs are poorly known, particularly in sites of importance for biodiversity. We assess the prevalence of potential OECMs in 740 terrestrial Key Biodiversity Areas (KBAs) outside known or mapped protected areas across ten countries. A majority of unprotected KBAs (76.5%) were at least partly covered by one or more potential OECMs. The conservation of ecosystem services or biodiversity was a stated management aim in 73% of these OECMs. Local or central government bodies managed the highest number of potential OECMs, followed by local and indigenous communities and private landowners. There was no difference between unprotected KBAs with or without OECMs in forest loss or in a number of state-pressure-response metrics

The Victorian Newsletter (Fall 1959)

The Victorian Newsletter is edited for the English X Group of the Modern Language Association by William E. Buckler, 737 East Building, New York University, New York 3, New York.Some pages are missing from this record

Pharmacokinetics of gemcitabine in non-small-cell lung cancer patients: impact of the 79A>C cytidine deaminase polymorphism

To study the impact of the 79A > C polymorphism in the cytidine deaminase (CDA) gene on the pharmacokinetics of gemcitabine and its metabolite 2',2'-difluorodeoxyuridine (dFdU) in non-small-cell lung cancer (NSCLC) patients. Patients (n = 20) received gemcitabine 1,125 mg/m(2) as a 30 min i.v. infusion as part of treatment for NSCLC. Plasma samples were collected during 0-6 h after gemcitabine administration. Gemcitabine and dFdU were quantified by high performance liquid chromatography with ultraviolet detection. The CDA 79A > C genotype was determined with PCR and DNA sequencing. Gemcitabine was rapidly cleared from plasma and undetectable after 3 h. The allele frequency of the 79A > C polymorphism was 0.40. Diplotypes were distributed as A/A n = 8, A/C n = 8 ,and C/C n = 4. No significant differences were found between the different CDA genotypes and gemcitabine or dFdU AUC, clearance, or half-life. The 79A > C polymorphism in the CDA gene does not have a major consistent and signficant impact on gemcitabine pharmacokinetics