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This work presents a model-theoretic approach to the study of the amalgamation property for varieties of semilinear commutative residuated lattices. It is well-known that if a first-order theory T enjoys quantifier elimination in some language L, the class of models of the set of its universal consequences $${\rm T_\forall}$$ has the amalgamation property. Let $${{\rm Th}(\mathbb{K})}$$ be the theory of an elementary subclass $${\mathbb{K}}$$ of the linearly ordered members of a variety $${\mathbb{V}}$$ of semilinear commutative residuated lattices. We show that whenever $${{\rm Th}(\mathbb{K})}$$ has elimination of quantifiers, and every linearly ordered structure in $${\mathbb{V}}$$ is a model of $${{\rm Th}_\forall(\mathbb{K})}$$, then $${\mathbb{V}}$$ has the amalgamation property. We exploit this fact to provide a purely model-theoretic proof of amalgamation for particular varieties of semilinear commutative residuated lattices. [ABSTRACT FROM AUTHOR]

We introduce a method of reducing the q-Member p-Committee Problem for an arbitrary finite system of sets to the same problem for a system of sets of smaller size and with a smaller number of subsystems with nonempty intersection maximal with respect to inclusion. For p = 1/2, for an infeasible system of linear inequalities in ℝ we give an efficient implementation of this method with complexity polynomial in the number of inequalities and the number of committee elements, but exponential in the dimension of the space. For this implementation, we give experimental results for n = 2, 3. [ABSTRACT FROM AUTHOR]

Abstract: The paper discusses a general methodology to the design of recursive Gaussian filters to be used for separating the form, waviness and roughness components of the surface texture. By selecting appropriate initial values for the filter difference equations, it is possible to eliminate the so-called edge effect and evaluate the whole registered profile. Two ways of filter implementation were considered: series and parallel. The incremental difference operator is applied in place of the usual shift operator z to describe the filter transfer function. This increases the accuracy of the representation of filter parameters and decreases the number of rounding errors. The results of the analysis were illustrated using 2D and 3D roughness profiles of a ball bearing race. The data show that the mean line and the mean surface were correctly determined for the whole area of the measured profile. [Copyright &y& Elsevier]

Abstract: We present a method for finding optimal controlled variables, which are polynomial combinations of measurements. Controlling these variables gives optimal steady state operation. Our work extends the concept of self-optimizing control; starting from the first-order necessary optimality conditions, any unknown variables are eliminated using elimination theory for polynomial systems to obtain invariant variable combinations, which contain only known variables (measurements). If a disturbance causes the active constraints to change, the invariants may be used to identify, and switch to the right region. This makes the method applicable over a wide disturbance range with changing active sets. The procedure is applied to two case studies of continuous stirred tank reactors. [Copyright &y& Elsevier]

In this paper we define a new type of connexive logics which we call Boolean connexive logics. In such logics negation, conjunction and disjunction behave in the classical, Boolean way. We determine these logics through application of the relating semantics. In the final section we present a tableau approach to the discussed logics. [ABSTRACT FROM AUTHOR]

In this study, a new paraconsistent four-valued logic called biclassical connexive logic (BCC) is introduced as a Gentzen-type sequent calculus. Cut-elimination and completeness theorems for BCC are proved, and it is shown to be decidable. Duality property for BCC is demonstrated as its characteristic property. This property does not hold for typical paraconsistent logics with an implication connective. The same results as those for BCC are also obtained for MBCC, a modal extension of BCC. [ABSTRACT FROM AUTHOR]

Efficient scheduling is critical for achieving improved performance of distributed applications where an application is to be considered as a group of interrelated tasks and represented by a task graph. In this work, we present a clustering-based scheduling algorithm called effective critical path (ECP) to schedule precedence constrained tasks on multiprocessor computing systems. The main aim of the algorithm is to minimize the schedule length of the given application. It uses the concept of edge zeroing on the critical path of the task graph for clustering the tasks of an application. An experimental analysis is performed using random task graphs and the task graphs derived from the real-world applications such as Gaussian Elimination, fast Fourier transform and systolic array. The results illustrate that the ECP algorithm gives better performance than the previous algorithms, considered herein, in terms of the average normalized schedule length and average speedup. [ABSTRACT FROM AUTHOR]

We present a proof-theoretical analysis of the theory of definite descriptions which emerges from Frege's approach and was formally developed by Kalish and Montague. This theory of definite descriptions is based on the assumption that all descriptions are treated as genuine terms. In particular, a special object is chosen as a designatum for all descriptions which fail to designate a unique object. Kalish and Montague provided a semantical treatment of such theory as well as complete axiomatic and natural deduction formalization. In the paper we provide a sequent calculus formalization of this logic and prove cut elimination theorem in the constructive manner. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we present two new algorithmic variants to compute the Neville elimination, with and without pivoting, which improve data locality and cast most of the computations in terms of high-performance Level 3 BLAS. The experimental evaluation on a state-of-the-art multi-core processor demonstrates that the new blocked algorithms exhibit a much higher degree of concurrency and better cache usage, yielding higher performance while offering numerical accuracy akin to that of the traditional columnwise variant in most cases. [Copyright &y& Elsevier]

This paper describes several parallel algorithmic variations of the Neville elimination. This elimination solves a system of linear equations making zeros in a matrix column by adding to each row an adequate multiple of the preceding one. The parallel algorithms are run and compared on different multi- and many-core platforms using parallel programming techniques as MPI, OpenMP and CUDA. [ABSTRACT FROM AUTHOR]

Abstract: Elimination methods are highly effective for the solution of linear and nonlinear systems of equations, but reversal of the elimination principle can be beneficial as well: competent incorporation of additional independent constraints and variables or more generally immersion of the original computational problem into a larger task, defined by a larger number of independent constraints and variables can improve global convergence of iterative algorithms, that is their convergence from the start. A well known example is the dual linear and nonlinear programming, which enhances the power of optimization algorithms. We believe that this is just an ad hoc application of general Principle of Expansion with Independent Constraints; it should be explored systematically for devising iterative algorithms for the solution of equations and systems of equations and for optimization. At the end of this paper we comment on other applications and extensions of this principle. Presently we show it at work for the approximation of a single zero of a univariate polynomial of a degree . Empirical global convergence of the known algorithms for this task is much weaker than that of the algorithms for all zeros, such as Weierstrass–Durand–Kerner’s root-finder, which reduces its root-finding task to Viète’s (Vieta’s) system of polynomial equations with unknowns. We adjust this root-finder to the approximation of a single zero of , preserve its fast global convergence and decrease the number of arithmetic operations per iteration from quadratic to linear. Together with computing a zero of a polynomial , the algorithm deflates this polynomial as by-product, and then could be reapplied to the quotient to approximate the next zero of . Alternatively by using processors that exchange no data, one can concurrently approximate up to zeros of . Our tests confirm the efficiency of the proposed algorithms. Technically our root-finding boils down to computations with structured matrices, polynomials and partial fraction decompositions. Our study of these links can be of independent interest; e.g., as by-product we express the inverse of a Sylvester matrix via its last column, thus extending the celebrated result of Gohberg and Sementsul (1972) from Toeplitz to Sylvester matrix inverses. [Copyright &y& Elsevier]

Abstract: In this paper we show that the intuitionistic theory for finitely many iterations of strictly positive operators is a conservative extension of Heyting arithmetic. The proof is inspired by the quick cut-elimination due to G. Mints. This technique is also applied to fragments of Heyting arithmetic. [Copyright &y& Elsevier]

Coordinated experimental and orthogonal space random walk (OSRW) molecular dynamics simulation studies were performed to understand the exceptionally low temperature required for thermal conversion of a poly(phenylenevinylene) (PPV) precursor containing the macromolecular counterion poly(ethylene glycol)-4-nonylphenyl-3-sulfopropyl ether (PEGNOPS). Simulations of this solvent-free system converged for starting points where the backbone was artificially expanded or compressed. In this example of a polymer organized by a polymer, the simulations revealed the ability of PEGNOPS to partially preorder the precursor chain in a conformation that favors the E2 elimination pathway. [ABSTRACT FROM AUTHOR]

In this paper we study the termination behavior of Russell’s description elimination rewrite system. We discuss certain claims made by Kripke (2005) in his paper concerning the possible nontermination of elimination of descriptions. [ABSTRACT FROM AUTHOR]

Abstract: Newton, in notes that he would rather not have seen published, described a process for solving simultaneous equations that later authors applied specifically to linear equations. This method — which Euler did not recommend, which Legendre called “ordinary,” and which Gauss called “common” — is now named after Gauss: “Gaussian” elimination. Gauss’s name became associated with elimination through the adoption, by professional computers, of a specialized notation that Gauss devised for his own least-squares calculations. The notation allowed elimination to be viewed as a sequence of arithmetic operations that were repeatedly optimized for hand computing and eventually were described by matrices. [Copyright &y& Elsevier]

Abstract: The elimination of whip using electromagnetic exciters (EEs) is investigated in this paper. First, mathematical models of a rotor-bearing system are derived. The threshold of instability determining if the rotor-bearing system experiences fluid-induced instability is obtained. Then, an experimental rotor-bearing system is designed and constructed to justify the elimination of whip, and orbit, spectrum, and spectrum cascade plots are obtained from the experimental data. The proposed procedure applies root locus plots to simulate the threshold of instability, and the spring model is used to compute the stiffness that the system needs to address the whip problem. Moreover, design examples are illustrated to explain the calculation process that tackles the proportional (simulating stiffness) and derivative (simulating damping) parameters of the EE to improve the stiffnesses of the rotor-bearing system. The main contribution of the present experimental work is that by using the EE it is possible to increase the stiffness of the rotor-bearing system and lead to the rotor-bearing system with a higher threshold of stability and eliminate the whip instability. [ABSTRACT FROM AUTHOR]

Abstract: Neville elimination is a direct method for solving linear systems. Several pivoting strategies for Neville elimination, including pairwise pivoting, are analyzed. Bounds for two different kinds of growth factors are provided. Finally, an approximation of the average normalized growth factor associated with several pivoting strategies is computed and analyzed using random matrices. [ABSTRACT FROM AUTHOR]

As the only nonlinear operation, masked S-box is the core to resist differential power attack (DPA) for advanced encryption standard (AES) cipher chips. In order to suit for the resource-constrained applications, a compact masked S-box based on composite field is proposed in this paper. Firstly, the architecture of masked S-box is designed with composite field masking method. Secondly, four masked S-boxes based on GF ((24)2), which are based on four basis methods with the optimal coefficient and the corresponding optimal root, are implemented and optimized by the delay-aware common subexpression elimination (DACSE) algorithm. Finally, experimental results show that, while maintaining the DPA-resistance performance, our best masked S-box achieves better area performance with the fastest speed compared with the existing works. Therefore, our masked S-box is suitable for resource-constrained applications with fast speed requirements. [ABSTRACT FROM AUTHOR]

This study tested the load transfer effectiveness of cast-joined structures under flexural loading conditions. Bars of Rexillium III alloy (Ni-Cr-Be) were tested under four-point bending conditions in an Instron testing machine. Six specimens were prepared for each of five interlocking designs. After wax elimination of the investment mold, new metal was cast into the central interlock area. Strain gauges were bonded across the interfaces between the as-cast and secondary cast structures on the bottom surface, and the specimens were loaded to failure in a four-point-bending fixture. Failure was assumed at a strain level of 0.1%, which corresponds to the tensile failure strain of feldspathic porcelain. Three as-cast bars were tested as controls. The average failure load of an interlock design used by Weiss and Munyon was significantly higher (P < 0.05) than that of the remaining four designs but was significantly lower (P < 0.05) than that of the solid bar. At the critical strain level of 0.1%, the load-transfer effectiveness of the Weiss and Munyon design was less than 22%. The results suggest that the cast-joining technique may increase the risk of failure in clinical situations where high flexural stresses exist. [ABSTRACT FROM AUTHOR]

We present a simplified approach of deriving the working dimensions between surfaces of a workpiece during tolerance charting. Unlike other methods, it does not require any representation of the machining sequence. The dimensional chains are first formulated into a matrix and it is then solved by applying the Gauss elimination technique. We also describe an elegant method of deriving the balanced tolerances of a workpiece during tolerance charting. The process links between surfaces are derived by using a special tracing technique. With the process links obtained, the balanced tolerances are solved by using a separate mathematical model. An example is used to illustrate the method. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we present some results showing the good behavior of the τ-invariant of a Rees algebra with integral closure and elimination (of variables). [ABSTRACT FROM AUTHOR]

Abstract: We propose an elimination mechanism in the study of the evolutionary prisoner’s dilemma games on evolving networks. It assumes that after each round of playing, players whose payoffs are below a certain threshold will be eliminated from the game and the same number of new nodes will be added to the network to maintain the size of the network constant. Numerical results show that moderate values of elimination threshold can result in a maximum cooperation level in the evolutionary prisoner’s dilemma game. Moreover, the elimination mechanism can make the network structure evolve into a high heterogeneity in degree distribution, which is considered to be helpful in promoting cooperation in evolutionary games. The present study may provide new insight for understanding the evolution of cooperation in light of the law ‘survival of the fittest’ in nature. [Copyright &y& Elsevier]

Abstract: Neville elimination is an elimination procedure alternative to Gaussian elimination. It is very useful when dealing with totally positive matrices, for which nice stability results are known. Here we include examples, most of them test matrices used in MATLAB which are not totally positive matrices, where Neville elimination outperforms Gaussian elimination. [Copyright &y& Elsevier]

Abstract: We study adjunct-elimination results for Context Logic applied to trees, following previous results by Lozes for Separation Logic and Ambient Logic. In fact, it is not possible to prove such elimination results for the original single-holed formulation of Context Logic. Instead, we prove our results for multi-holed Context Logic. [Copyright &y& Elsevier]

Abstract: An important property of chordal graphs is that these graphs are characterized by the existence of perfect elimination orderings on their vertex sets. In this paper, we generalize the notion of perfect elimination orderings to signed graphs, and give a characterization for graphs admitting such orderings, together with characterizations restricted to some subclasses and further properties of those graphs. The definition of our generalized perfect elimination orderings is motivated by a generalization of the classical result that a so-called graphic hyperplane arrangement is free if and only if the corresponding graph is chordal. [Copyright &y& Elsevier]

Abstract: This paper studies the forward kinematics of a symmetrical 6-6 Stewart platform, in which both the base and the mobile platform are hexagons and the joint centers satisfy some conditions. A concise algebraic elimination algorithm to solve the closed-form forward kinematics of the Stewart platform is presented. Based on the presented algebraic method, an interesting result that comes out of our study is that the forward kinematics problem is reduced to solve a univariate polynomial equation of degree at most 14. The 14th degree univariate polynomial is derived from the determinant of the 15×15 Sylvester’s matrix, which is relatively small in size, without factoring out or deriving the greatest common divisor. The algorithm is comparatively concise and requires fairly less computation time. The result is verified by a numerical example. [Copyright &y& Elsevier]

Abstract: We develop in this paper methods for studying the implicitization problem for a rational map defining a hypersurface in , based on computing the determinant of a graded strand of a Koszul complex. We show that the classical study of Macaulay resultants and Koszul complexes coincides, in this case, with the approach of approximation complexes and we study and give a geometric interpretation for the acyclicity conditions. Under suitable hypotheses, these techniques enable us to obtain the implicit equation, up to a power, and up to some extra factor. We give algebraic and geometric conditions for determining when the computed equation defines the scheme theoretic image of ϕ, and, what are the extra varieties that appear. We also give some applications to the problem of computing sparse discriminants. [Copyright &y& Elsevier]

Roger Crisp distinguishes a positive and a negative aspect of the buck-passing account of goodness (BPA), and argues that the positive account should be dropped in order to avoid certain problems, in particular, that it implies eliminativism about value. This eliminativism involves what I call an ontological claim, the claim that there is no real property of goodness, and an error theory, the claim that all value talk is false. I argue first that the positive aspect of the BPA is necessary to explain the negative aspect. I accept the ontological claim but argue that this does not imply any sort of error theory about value. [ABSTRACT FROM AUTHOR]

Abstract: An improved algorithm, together with its implementation, is presented for the automatic computation of the complete root classification of a real parametric polynomial. The algorithm offers improved efficiency and a new test for non-realizable conditions. The improvement lies in the direct use of ‘sign lists’, obtained from the discriminant sequence, rather than ‘revised sign lists’. It is shown that the discriminant sequences, upon which the sign lists are based, are closely related both to Sturm–Habicht sequences and to subresultant sequences. Thus calculations based on any of these quantities are essentially equivalent. One particular application of complete root classifications is the determination of the conditions for the positive definiteness of a polynomial, and here the new algorithm is applied to a class of sparse polynomials. It is seen that the number of conditions for positive definiteness remains surprisingly small in these cases. [Copyright &y& Elsevier]

Abstract: We first look at an existing infinitary sequent system for common knowledge for which there is no known syntactic cut-elimination procedure and also no known non-trivial bound on the proof-depth. We then present another infinitary sequent system based on nested sequents that are essentially trees and with inference rules that apply deeply inside these trees. Thus we call this system “deep” while we call the former system “shallow”. In contrast to the shallow system, the deep system allows one to give a straightforward syntactic cut-elimination procedure. Since both systems can be embedded into each other, this also yields a syntactic cut-elimination procedure for the shallow system. For both systems we thus obtain an upper bound of on the depth of proofs, where is the Veblen function. [Copyright &y& Elsevier]

Abstract: In the paper we propose a new algorithm for the determination of peaks containing regions and their separation from peak-free regions. Further based on this algorithm we propose a new background elimination algorithm which allows more accurate estimate of the background beneath the peaks than the algorithms known so far. The algorithm is based on a clipping operation with the window adjustable automatically to the widths of identified peak regions. The illustrative examples presented in the paper prove in favor of the proposed algorithms. [Copyright &y& Elsevier]

Abstract: Elimination Game is a well-known algorithm that simulates Gaussian elimination of matrices on graphs, and it computes a triangulation of the input graph. The number of fill edges in the computed triangulation is highly dependent on the order in which Elimination Game processes the vertices, and in general the produced triangulations are neither minimum nor minimal. In order to obtain a triangulation which is close to minimum, the Minimum Degree heuristic is widely used in practice, but until now little was known on the theoretical mechanisms involved. In this paper we show some interesting properties of Elimination Game; in particular that it is able to compute a partial minimal triangulation of the input graph regardless of the order in which the vertices are processed. This results in a new algorithm to compute minimal triangulations that are sandwiched between the input graph and the triangulation resulting from Elimination Game. One of the strengths of the new approach is that it is easily parallelizable, and thus we are able to present the first parallel algorithm to compute such sandwiched minimal triangulations. In addition, the insight that we gain through Elimination Game is used to partly explain the good behavior of the Minimum Degree algorithm. We also give a new algorithm for producing minimal triangulations that is able to use the minimum degree idea to a wider extent. [Copyright &y& Elsevier]

A double-elimination tournament (DET) eliminates a team only when the team has lost twice. It is a viable alternative to a single-elimination tournament when we have time for more matches, or we wish every team to have more than one chance to demonstrate its ability. Despite its popularity, DETs have not been studied thoroughly. In this paper we propose a new DET as an alternative to the commonly Used DET This new format makes the tournament shorter, allows the better teams to play more matches, and makes most matches more competitive. Furthermore, the best team has a higher probability to win the championship in most cases. The new DET has many advantages when compared with the current FIFA World Cup™ tournament which requires approximately the same number of matches. [ABSTRACT FROM AUTHOR]

Abstract: We extend the recently proposed state-space restriction (SSR) technique for quantum spin dynamics simulations [Kuprov et al., J. Magn. Reson. 189 (2007) 241–250] to include on-the-fly detection and elimination of unpopulated dimensions from the system density matrix. Further improvements in spin dynamics simulation speed, frequently by several orders of magnitude, are demonstrated. The proposed zero track elimination (ZTE) procedure is computationally inexpensive, reversible, numerically stable and easy to add to any existing simulation code. We demonstrate that it belongs to the same family of Krylov subspace techniques as the well-known Lanczos basis pruning procedure. The combined SSR+ZTE algorithm is recommended for simulations of NMR, EPR and Spin Chemistry experiments on systems containing between 10 and 104 coupled spins. [Copyright &y& Elsevier]

Abstract: The reactions of Pd+ and Pt+ with CS2 have been investigated at B3LYP, CCSD(T) and QCISD(T) levels of theory. Both Pd+ and Pt+ are found to be able to activate the C–S bond in CS2 and produce the products PdS+ and PtS+ through insertion–elimination mechanism. For both Pd+ and Pt+ the spin-forbidden reaction 2M+ +CS2 → 4MS+ +CS is found to be energetically more favorable than the spin-allowed reaction 2M+ +CS2 → 2MS+ +CS. According to the identified reaction mechanisms and PESs, the doublet–quartet surface-crossing is presumed to occur at the exit channel of the reaction. The reactions of Ni+, Pd+ and Pt+ with CS2 are systematically compared in reaction mechanism and potential energy surface. Although all these reactions exhibit obvious endothermic feature, comparisons of these reactions indicate that the reaction of Pt+ with CS2 is energetically much more favorable. The calculated results well rationalize the experimental observations. [Copyright &y& Elsevier]

Abstract: In functional brain mapping, pattern recognition methods allow detecting multivoxel patterns of brain activation which are informative with respect to a subject''s perceptual or cognitive state. The sensitivity of these methods, however, is greatly reduced when the proportion of voxels that convey the discriminative information is small compared to the total number of measured voxels. To reduce this dimensionality problem, previous studies employed univariate voxel selection or region-of-interest-based strategies as a preceding step to the application of machine learning algorithms. Here we employ a strategy for classifying functional imaging data based on a multivariate feature selection algorithm, Recursive Feature Elimination (RFE) that uses the training algorithm (support vector machine) recursively to eliminate irrelevant voxels and estimate informative spatial patterns. Generalization performances on test data increases while features/voxels are pruned based on their discrimination ability. In this article we evaluate RFE in terms of sensitivity of discriminative maps (Receiver Operative Characteristic analysis) and generalization performances and compare it to previously used univariate voxel selection strategies based on activation and discrimination measures. Using simulated fMRI data, we show that the recursive approach is suitable for mapping discriminative patterns and that the combination of an initial univariate activation-based (F-test) reduction of voxels and multivariate recursive feature elimination produces the best results, especially when differences between conditions have a low contrast-to-noise ratio. Furthermore, we apply our method to high resolution (2 × 2 × 2mm3) data from an auditory fMRI experiment in which subjects were stimulated with sounds from four different categories. With these real data, our recursive algorithm proves able to detect and accurately classify multivoxel spatial patterns, highlighting the role of the superior temporal gyrus in encoding the information of sound categories. In line with the simulation results, our method outperforms univariate statistical analysis and statistical learning without feature selection. [Copyright &y& Elsevier]

This paper proposes a robust and accurate method for measuring 3-D surfaces using a binocular system. To eliminate the effect caused by the distortion of projector lens, each structured light sheet is fitted to a conicoid. A curvilinear detector, which combines the zero-crossing detection algorithm with Steger's detector, is employed to detect the sub pixel locations of the light stripes, thus preventing the Steger's curvilinear detector from failing to detect them in the end points of the stripes. The proposed coding method combines the information of the linked line with the gray code to avoid producing outliers caused by erroneous decoding and make the coding procedure more robust. Experiments showed that each structured light sheet fitted to a conicoid can effectively improve the measurement accuracy. The subpixel detection method can detect the exact sub pixel locations of the stripes. Likewise, the encoding strategy results in the production of fewer outliers, while the reconstruction result becomes more perfect. [ABSTRACT FROM AUTHOR]

Abstract: This paper proves the strong normalization of classical natural deduction with disjunction and permutative conversions, by using CPS-translation and augmentations. Using them, this paper also proves the strong normalization of classical natural deduction with general elimination rules for implication and conjunction, and their permutative conversions. This paper also proves that natural deduction can be embedded into natural deduction with general elimination rules, strictly preserving proof normalization. [Copyright &y& Elsevier]

The essay discusses access to toilets as a factor in social justice. She states that distribution of toilets are a symbol and a concrete representation of social hierarchy. She points to toilets as a prerequisite to participation in public life and as a health issue for homeless persons and third world societies. She examines the neglect of the topic of elimination and of gender equity in bathrooms in scholarly discussions. She urges scholarly discussion and action on these topics.

Abstract: A simple cut elimination proof for arithmetic with the epsilon symbol is used to establish the termination of a modified epsilon substitution process. This opens a possibility of extension to much stronger systems. [Copyright &y& Elsevier]

The article focuses on the elimination of political gerrymandering by fair majority voting (FMV). Political gerrymandering is a practice of dividing geographical area into electoral districts to give one political party an unfair advantage by stretching the opposition's voting strength. It is stated that computer technology advancements have permitted a great leap forward of political gerrymandering. FMV is presented as the answer to political gerrymandering. In FMV, voters cast ballots in single-member districts but in voting for a candidate, each gives a vote to the candidate's party. The rules deciding the candidates to be elected is calculated by Jefferson's method of apportionment on the basis of total party votes and the candidates elected are determined through dual approach.

Summary: During development, the formation of mature neural circuits requires the selective elimination of inappropriate synaptic connections. Here we show that C1q, the initiating protein in the classical complement cascade, is expressed by postnatal neurons in response to immature astrocytes and is localized to synapses throughout the postnatal CNS and retina. Mice deficient in complement protein C1q or the downstream complement protein C3 exhibit large sustained defects in CNS synapse elimination, as shown by the failure of anatomical refinement of retinogeniculate connections and the retention of excess retinal innervation by lateral geniculate neurons. Neuronal C1q is normally downregulated in the adult CNS; however, in a mouse model of glaucoma, C1q becomes upregulated and synaptically relocalized in the adult retina early in the disease. These findings support a model in which unwanted synapses are tagged by complement for elimination and suggest that complement-mediated synapse elimination may become aberrantly reactivated in neurodegenerative disease. [Copyright &y& Elsevier]

Summary: The OspF family of phosphothreonine lyase, including SpvC from Salmonella, irreversibly inactivates the dual-phosphorylated host MAPKs (pT-X-pY) through β elimination. We determined crystal structures of SpvC and its complex with a phosphopeptide substrate. SpvC adopts a unique fold of α/β type. The disordered N terminus harbors a canonical D motif for MAPK substrate docking. The enzyme-substrate complex structure indicates that recognition of the phosphotyrosine followed by insertion of the threonine phosphate into an arginine pocket places the phosphothreonine into the enzyme active site. This requires the conformational flexibility of pT-X-pY, which suggests that p38 (pT-G-pY) is likely the preferred physiological substrate. Structure-based biochemical and enzymatic analysis allows us to propose a general acid/base mechanism for β elimination reaction catalyzed by the phosphothreonine lyase. The mechanism described here provides a structural understanding of MAPK inactivation by a family of pathogenic effectors conserved in plant and animal systems and may also open a new route for biological catalysis. [Copyright &y& Elsevier]

Abstract: The role of the base in the synthesis of 3′-deoxy-3′-[18F]fluorothymidine, [18F]FLT, via nucleophilic substitution of the nosyl group with [18F]fluoride was investigated. The rate of 18F-incorporation into the molecule dramatically changed as a function of the precursor-to-base ratio. In the presence of excess base, the precursor was consumed by elimination before substitution was complete. When the precursor-to-base ratio was optimal, an overall [18F]FLT yield of 30–40% was achieved even if the precursor amount was as small as 8–13mg. [Copyright &y& Elsevier]

Item test analysis is an aid to identify items that need to be eliminated from an assessment. An automatic elimination procedure based on item statistics, therefore, could help to increase the quality of a test in an objective manner. This was investigated by studying the effect of a standardized elimination procedure on the test results of a second-year course over a period of 6 successive years in 1,624 candidates. Cohort effects on the item elimination were examined by determining the number of additional items that had to be eliminated from three different tests in 3 successive academic years in two cohorts. The items that were part of more than one test and had to be eliminated according to the procedure in at least one of the tests appeared to have to be retained according to the same procedure in most of the other tests. The procedure harmed the high scoring students relatively more often than the other students, and the number of eliminated items appeared to be cohort dependent. As a consequence, automatic elimination procedures obscure the transparency of the grading process unacceptably and transform valid tests into inadequate samples of the course content. [ABSTRACT FROM AUTHOR]

Hyperthermal collisions of ground-state atomic oxygen with H2O have been investigated, with special attention paid to the H-atom elimination reaction, O(3P) H2O(X 1A1) → HO2(2A‘) H(2S). This reaction was observed in a crossed-beams experiment, and the relative excitation function in the region around its energy threshold (50−80 kcal mol-1) was measured. Direct dynamics calculations were also performed at two levels of theory, B3LYP/6-31G(d,p) and MP2/6-31G(d,p). The shape of the B3LYP excitation function closely matches that of the experiment. The calculations provided a detailed description of the dynamics and revealed a striking dependence of the reaction mechanism on collision energy, where the cross section rises from a threshold near 60 kcal mol-1to a peak at ∼115 kcal mol-1and then decreases at higher energies as secondary dissociation of the internally excited HO2product becomes dominant. The calculations show that the cross section for H-atom elimination (O H2O → HO2H) is about 10−25% that of the H-atom abstraction (O H2O → OH OH) cross section for collision energies in the 70−160 kcal mol-1range. [ABSTRACT FROM AUTHOR]

The results are reported of mass-spectrometric studies of the nucleobases adenine 1h (1, R = H), guanine 2h, and cytosine 3h. The protonated nucleobases are generated by electrospray ionization of adenosine 1r (1, R = ribose), guanosine 2r, and deoxycytidine 3d (3, R = deoxyribose) and their fragmentations were studied with tandem mass spectrometry. In contrast to previous EI-MS studies of the nucleobases, NH3 elimination does present a major path for the fragmentations of the ions [1h + H]+, [2h + H]+, and [3h + H]+. The ion [2h + H − NH3]+ also was generated from the acyclic precursor 5-cyanoamino-4-oxomethylene-dihydroimidazole 13h and from the thioether derivative 14h of 2h (NH2 replaced by MeS). The analyses of the modes of initial fragmentation is supported by density functional theoretical studies. Conjugate acids 15–55 were studied to determine site preferences for the protonations of 1h, 2h, 3h, 13h, and 14h. The proton affinity of the amino group hardly ever is the substrate’s best protonation site, and possible mechanisms for NH3 elimination are discussed in which the amino group serves as the dissociative protonation site. The results provide semi-direct experimental evidence for the existence of the pyrimidine ring-opened cations that we had proposed on the basis of theoretical studies as intermediates in nitrosative nucleobase deamination. [Copyright &y& Elsevier]

Heck-type 4-exo-trigcyclization of linear 2-enol triflate-1,5-hexadienes provides functionalized methylene cyclobutanes. Intramolecular palladium coordination can initiate -hydride elimination leading to 1,2-dimethylene cyclobutane derivatives, which are obtained with high selectivity if substrates having a geminal diphenyl group at Care used. In parallel, formal 5-endo-trigcyclization and -hydride elimination form 1-methylene cyclopent-2-en derivatives. [ABSTRACT FROM AUTHOR]

Abstract: For a tree T and an integer , it is well known that the kth power of T is strongly chordal and hence has a strong elimination ordering of its vertices. In this note we obtain a complete characterization of strongly simplicial vertices of , thereby characterizing all strong elimination orderings of the vertices of . [Copyright &y& Elsevier]

In the context of multiple constant multiplications (MCM) design, we propose a novel common-subexpression-elimination (CSE) algorithm that models synthesis of coefficients into an estimated cost function. Although the proposed algorithm generally does not guarantee an optimum solution, it is capable of finding the minimum/minima of the function in practically sized problems. In our design examples that have known optimal solutions, syntheses of coefficients using the proposed method match the optimal results in a defined search space. We also discover the relationhsip and propose an improvement search space for optimization that combine all minimal-signed-digit (MSD) representations as well as the shifted sum (difference) of coefficients to explore the hidden relationship. In some cases, the proposed feasible solution space further reduces the number of adders/subtractors in the synthesis of MCM from all MSD representations. [ABSTRACT FROM AUTHOR]