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Due to radiation-induced immune depression and development of pathologies such as cancer, there is increasing urgency to identify radiomitigators that are effective when administered after radiation exposure. The main goal of this study was to determine the radiomitigation capacity of MnTE-2-PyP[Mn(III) tetrakis (N-ethylpyridinium-2-yl) porphyrin], a superoxide dismutase (SOD) mimetic, and evaluate leukocyte parameters in spleen and blood. C57BL/6 mice were total-body exposed to 2 Gy γ-rays (Co-60), i.e., well below a lethal dose, followed by subcutaneous implantation of 5 × 105 RM-9 prostate tumor cells and initiation of MnTE-2-PyP treatment (day 0); interval between each procedure was 1–2 h. The drug was administered daily (12 times). Tumor progression was monitored and immunological analyses were performed on a subset per group on day 12. Animals treated with MnTE-2-PyP alone had significantly slower tumor growth compared to mice that did not receive the drug (P < 0.05), while radiation alone had no effect. Treatment of tumor-bearing mice with MnTE-2-PyP alone significantly increased spleen mass relative to body mass; the numbers of splenic white blood cells (WBC) and lymphocytes (B and T), as well as circulating WBC, granulocytes, and platelets, were high compared to one of more of the other groups (P < 0.05). The results show that MnTE-2-PyP slowed RM-9 tumor progression and up-regulated immune parameters, but mitigation of the effects of 2 Gy total-body irradiation were minimal.

In this paper we review the design of a sequential object oriented linear algebra library, O O L A L A . Several designs are proposed and used to classify existing sequential object oriented libraries. The classification is based on the way that matrices and matrix operations are represented. O O L A L A 's representation of matrices is capable of dealing with certain matrix operations that, although mathematically valid, are not handled correctly by existing libraries. O O L A L A also enables implementations of matrix calculations at various abstraction levels ranging from the relatively low-level abstraction of a Fortran BLAS-like implementation to higher-level abstractions that hide many implementation details. O O L A L A addresses a wide range of numerical linear algebra functionality while the reviewed object oriented libraries concen trate on parts of such functionality. We include some preliminary performance results for a Java implementation of O O L A L A .

We address the problem of implementing globally adaptive algorithms for multi-dimensional quadrature on parallel computers. By adapting and extending algorithms which we have developed for one-dimensional quadrature we develop algorithms for the multi-dimensional case. The algorithms are targeted at the latest generation of parallel computers, and are therefore independent of the network topology. Numerical results on a Kendall Square Research KSR-1 are reported.

Self-assembled mono- and multilayer films have been formed via selective ionic interactions. 1 Two types of molecule have been used, straight chain mercaptoalkanoic acids and those containing chromophores : HS(CH 2 ) 15 COOH and HS(CH 2 ) 11 O-C 8 H 4 -SO 2 (CH 2 ) 5 COOH. To better understand the formation process, XPS studies have been performed. Models are presented for various possible orientational structures, and evidence for a preferred orientation is given. The oxidation state of the copper ions within the films has been unambiguously determined.

We review the parallel quasi-Newton optimisation algorithms of Straeter [24] and van Laarhoven [25] and point out the possible drawbacks of these algorithms. By including Davidon [7] projections in the variable metric updating we can generalise Straeter's algorithm to a family of parallel projected quasi-Newton algorithms which do not suffer the above drawbacks and which retain quadratic termination. We consider the implementation of this parallel algorithm on the Intel iPSC/2 Hypercube. Finally we compare, on several standard example problems, the numerical performance of this new algorithm with Straeter's parallel algorithm and with a sequential quasi-Newton (BFGS) algorithm.

The problem of factorising an n th-degree polynomial P n ( x ) = x n + a 1 x n −1 + ⋯ + a n −1 x + a n , where the coefficients a i are real, into two polynomials Q ( x ) and R ( x ) of degrees n Q and n R can be posed as a system of n quadratic equations. An efficient implementation of Newton's method for the solution of these equations is achieved by exploiting the block Toeplitz structure of the Jacobian matrix which arises when n Q and n R are restricted to { m − 1, m , m + 1∣ m = [ 1 2 n ]}, where [ x ] is the largest integer ⩽ x . This polynomial factorisation permits the development of a divide and conquer method for the simultaneous calculation of all the zeros of a polynomial.

OoLaLa is an object oriented linear algebra library designed to reduce development and maintenance effort [2]. In contrast with traditional (Fortran-based) libraries, it provides two high abstraction levels that significantly reduce the combinatorial number of implementations necessary for particular linear algebra operations. Traditional libraries sacrifice abstraction for performance and their implementations of matrix operations have embedded knowledge about the data structures, storage formats (SFs), and special characteristics, matrix properties (MPs). These implementations are said to be at Storage Format Abstraction level (SFA-level). The first higher abstraction level, Matrix Abstraction level (MA-level), provides indexed random access to matrix elements. The second higher abstraction level, Iterator Abstraction level (IA-level), is based on the iterator pattern and provides sequential access to nonzero matrix elements.Performance results of a Java version of OoLaLa show that MA-level and IA-level are not competitive with SFA-level and motivate the two questions addressed in this poster: (1) how can implementations at MA-level and IA-level be transformed into the more efficient SFA-level? and (2) for which sets of SFs and MPs can this be done automatically?The latter question is addressed by the definition of a subset of MPs, linear combination matrix property (LCMP), and a subset of SFs, constant time element access storage format (CTSF). The set LCMP is defined as the subset of MPs such that every MP is based on a boolean expression involving linear combinations of the indices i and j to determine whether an element aij might be a nonzero element. An example of a LCMP is the upper triangular property (i.e. aij is zero when iρj). The set CTSF is defined as the subset of SFs such that matrix elements can be accessed in constant time. An example of an CTSF is the dense format; i.e. a two-dimensional array. The former question is tackled by a sequence of standard compiler transformations which is as follows: (1) method inlining, (2) move the guards1 for the inlined methods to surround the loop (or loops) and include nullity test for every object, (3) remove try-catch and throw clauses, (4) make local copies of the accessed attributes (class and instance variables), (5) disambiguate aliases, (6) remove redundant computations, and (7) transform while-loops into for-loops. Note that outside the scope of this work are loop restructuring transformations for the generation of block or recursive code. This sequence is not only beneficial for OoLaLa, but also for other libraries based on arrays (e.g. the JSR-0832 Array-List, Hash-Map and Hash-Set). Further information can be found in [1].

Hypoxia is a common environmental stress that regulates gene expression and cell function. A number of hypoxia-regulated transcription factors have been identified and have been shown to play critical roles in mediating cellular responses to hypoxia. One of these is the endothelial PAS-domain protein 1 (EPAS1/HIF2-alpha/HLF/HRF). This protein is 48% homologous to hypoxia-inducible factor 1-alpha (HIF1-alpha). To date, virtually nothing is known about the signaling pathways that lead to either EPAS1 or HIF1-alpha activation. Here we show that EPAS1 is phosphorylated when PC12 cells are exposed to hypoxia and that p42/p44 MAPK is a critical mediator of EPAS1 activation. Pretreatment of PC12 cells with the MEK inhibitor, PD98059, completely blocked hypoxia-induced trans-activation of a hypoxia response element (HRE) reporter gene by transfected EPAS1. Likewise, expression of a constitutively active MEK1 mimicked the effects of hypoxia on HRE reporter gene expression. However, pretreatment with PD98059 had no effect on EPAS1 phosphorylation during hypoxia, suggesting that MAPK targets other proteins that are critical for the trans-activation of EPAS1. We further show that hypoxia-induced trans-activation of EPAS1 is independent of Ras. Finally, pretreatment with calmodulin antagonists nearly completely blocked both the hypoxia-induced phosphorylation of MAPK and the EPAS1 trans-activation of HRE-Luc. These results demonstrate that the MAPK pathway is a critical mediator of EPAS1 activation and that activation of MAPK and EPAS1 occurs through a calmodulin-sensitive pathway and not through the GTPase, Ras. These results are the first to identify a specific signaling pathway involved in EPAS1 activation.

The problem of finding all the zeros of a polynomialP n (x)=x n +an−1xn−1+...+a1x+a0, where the coefficientsa i are real, can be posed as a system ofn nonlinear equations. The structure of this system allows an efficient numerical solution using a damped Newton method; in particular it is possible to generate the triangular factors of the associated Jacobian matrix directly. This approach provides a natural generalisation of the well-known method of Durand and Kerner.

Some promising ideas for minimizing a nonlinear function, whose first and second derivatives are given, by a modified Newton method, were introduced by Fiacco and McCormick (Ref. 1). Unfortunately, in developing a method around these ideas, Fiacco and McCormick used a potentially unstable, or even impossible, matrix factorization. Using some recently developed techniques for factorizing an indefinite symmetric matrix, we are able to produce a method which is similar to Fiacco and McCormick's original method, but avoids the difficulties of the original method.

This report is a summary of an evaluation of the weather data set, generated at Sandia Laboratories, known as the Typical Meteorological Year (TMY) Data. The purpose of the evaluation is to determine how well the TMY data represent actual long-term weather data in affecting the performance of solar heating and cooling systems. The two data sets are compared through detailed SHAC simulation.