Papers by Undefined Exception
Automatic di erentiation uses recurrence relations based on the rules of calculus. Consequently, ... more Automatic di erentiation uses recurrence relations based on the rules of calculus. Consequently, the results are guaranteed to be correct only if the relevant mathematical assumptions are satis ed at least in a neighborhood of the current argument. Computer programs may violate these conditions by branching or by calling intrinsic functions such as abs, max, sqrt, and asin at points where their derivative is unde ned or in nite. The resulting dependence between the program's input and output variables may still be di erentiable, because branch values t together smoothly or nondi erentiabilities cancel each other out.
Journal of Economic Geography, 2003
International Journal of Forecasting, 2009
This paper identifies forecasts of exceptions in product or service demand (i.e., large changes o... more This paper identifies forecasts of exceptions in product or service demand (i.e., large changes or extreme values) as a special need in forecasting, requiring new forecast accuracy measures based on the tails of sampled forecast error distributions. For this purpose, the paper introduces application of the receiver operating characteristic (ROC) framework, which has been used to assess exceptional behavior or cases in many fields. The "exception principle" of management reporting provides the corresponding forecast requirements. Seasonality estimates in univariate forecast models and leading independent variables in multivariate forecast models are among the approaches to forecasting exceptions. In a case study on serious violent crime in Pittsburgh, Pennsylvania across small sub-areas of the city, the simplest, nonnaïve univariate forecast method is best for forecasting ordinary conditions, as found in previous research using conventional forecast accuracy measures, but the most complex multivariate model is best for forecasting exceptional conditions, using ROC forecast accuracy measures.
British Journal of Ophthalmology, 1993
The prevalence of human T ceil lymphoma virus type 1 (HTLV-I) was studied among patients with end... more The prevalence of human T ceil lymphoma virus type 1 (HTLV-I) was studied among patients with endogenous uveitis. Twelve (15.8%) of 76 uveitis patients with known aetiology or clinical entity were seropositive, the prevalence being comparable with that in the general population of the southwestern area of Japan where HTLV-I is highly endemic. In the comparison, 32 (41-0%) of 78 patients with aetiology or entity undefined uveitis were seropositive for HTLV-I, which indicated a signifcantly higher seroprevalence than controls matched for sex and age. The 32 cases of clinical entity undefined, HTLV-I positive uveitis were characterised by acute granulomatous or non-granulomatous uveal reactions which were accompanied by vitreous opacities and retinal vasculitis. The uveal inflammatory and retinal vascular changes responded weli to topical and/or systemic corticosteroids and resolved in a few weeks in the majority of cases with favourable visual outcome. The disease affected one or both eyes, and eight cases (25%) showed recurrence within a year. The general condition of the patients remained well otherwise during a foliow up study (mean follow up time 15*4 months), except for three cases with a possible association of hyperthyroidism. These findings provide additional information favouring an association between HTLV-I and isolated uveitis, a new disease entity which should be termed HTLV-I-associated uveitis.
ACM Sigada Ada Letters, 2001
The GNAT/ORK cross-compilation system was designed to support the Ravenscar profile semantics in ... more The GNAT/ORK cross-compilation system was designed to support the Ravenscar profile semantics in a simple and efficient way. The implementation of the underlying kernel support for the exception handling was not difficult, but it raised two main issues. First, the handling of certain exceptions (namely task termination and elaboration) is undefined in the Ravenscar profile. Second, the kernel mechanism required to support Ada exceptions (using the GNAT runtime) is very simple if we do not adhere to the complex POSIX signal approach.
Microbiology, 2008
A systematic analysis of the inheritance of D plasmids of the IncP-9 group ( α -, β -, γ -, δ -, ... more A systematic analysis of the inheritance of D plasmids of the IncP-9 group ( α -, β -, γ -, δ -, ε -, ζ -, η -, and θ -subgroups), IncP-7, as well as of those of undefined systematic affiliation in the cells of homologous ( Pseudomonas putida ) and heterologous ( Escherichia coli ) hosts was performed for the first time. For this purpose, mini-Tn5 transposons determining resistance to kanamycin (or streptomycin) were introduced into all the D plasmids under study. It has been established that all IncP-9 plasmids can be transmitted to the cells of a heterologous host E . coli (with the exception of plasmid pSVS15 from θ -subgroup). IncP-7 plasmids and those of undefined systematic affiliation do not possess this property and can be transmitted and stably inherited only in P . putida . The distinctive feature of most IncP-9 plasmids ( α -, β -, δ -, ε -, and ζ -subgroups) is strict dependence of their inheritance on the temperature factor. At 37°C , the plasmids of δ -, ζ -, and θ -subgroups are unstable in P . putida cells, while in E . coli nearly all plasmids of this systematic group are unstable. The exceptions are the plasmids of ηand γ -subgroups. Inheritance of these plasmids does not depend on temperature. At 28 ° C and 37°C , the η plasmid is not maintained stably (inheritance stability is 2%), while the γ plasmid has almost 100% stability.
Comparison of the Spherical Model and the Clapp-Moss Equations with the Ising Model
Physical Review, 1968
Backward-compatible constant-time exception-protected memory
ABSTRACT We present a novel, table-free technique for detecting all temporal and spatial memory a... more ABSTRACT We present a novel, table-free technique for detecting all temporal and spatial memory access errors (eg dangling pointers, out-of-bounds check, etc.) in programs supporting general pointers. Our approach is the first technique to provide such error checking using only ...
A humanized model for multiple sclerosis using HLA-DR2 and a human T-cell receptor
Nature Genetics, 1999
Multiple sclerosis (MS) is a complex chronic neurologic disease with a suspected autoimmune patho... more Multiple sclerosis (MS) is a complex chronic neurologic disease with a suspected autoimmune pathogenesis. Although there is evidence that the development of MS is determined by both environmental influences and genes, these factors are largely undefined, except for major histocompatibility (MHC) genes. Linkage analyses and association studies have shown that susceptibility to MS is associated with genes in the human histocompatibility leukocyte antigens (HLA) class II region, but the contribution of these genes to MS disease development less compared with their contribution to disorders such as insulin-dependent diabetes mellitus. Due to the strong linkage disequilibrium in the MHC class II region, it has not been possible to determine which gene(s) is responsible for the genetic predisposition. In transgenic mice, we have expressed three human components involved in T-cell recognition of an MS-relevant autoantigen presented by the HLA-DR2 molecule: DRA*0101/DRB1*1501 (HLA-DR2), an MHC class II candidate MS susceptibility genes found in individuals of European descent; a T-cell receptor (TCR) from an MS-patient-derived T-cell clone specific for the HLA-DR2 bound immunodominant myelin basic protein (MBP) 4102 peptide; and the human CD4 coreceptor. The amino acid sequence of the MBP 84-102 peptide is the same in both human and mouse MBP. Following administration of the MBP peptide, together with adjuvant and pertussis toxin, transgenic mice developed focal CNS inflammation and demyelination that led to clinical manifestations and disease courses resembling those seen in MS. Spontaneous disease was observed in 4% of mice. When DR2 and TCR double-transgenic mice were backcrossed twice to Rag2 (for recombination-activating gene 2)-deficient mice, the incidence of spontaneous disease increased, demonstrating that T cells specific for the HLA-DR2 bound MBP peptide are sufficient and necessary for development of disease. Our study provides evidence that HLA-DR2 can mediate both induced and spontaneous disease resembling MS by presenting an MBP self-peptide to T cells.
Journal of Biological Inorganic Chemistry, 1998
The effect of axial ligand nodal plane orientation on the contact and pseudocontact shifts of a ... more The effect of axial ligand nodal plane orientation on the contact and pseudocontact shifts of a symmetrical low-spin octamethylferriheme center has been calculated as a function of the angle of the axial ligand. Simple Hückel techniques have been used to estimate the contact contribution, and values obtained from model hemes, together with counter-rotation of the g-tensor, have been used to estimate the pseudocontact contribution, for the eight β-pyrrole methyl and four meso-H positions. It is found that the maximum and minimum contact shifts occur when the axial ligand is aligned at an angle of ±15° to the meso-H axes of the heme, rather than when the axial ligand plane lies along the porphyrin nitrogens, as assumed previously by some investigators. For systems having one planar axial ligand or two ligands in parallel planes, the contact and pseudocontact contributions at the meso-H positions are comparable in size (at least on the basis of simple Hückel estimates), while the contact contribution clearly dominates the isotropic shifts of the heme methyls. Allowing for the substituent effect of the 2,4-vinyls of protohemin, or the 2,4-thioethers of hemin c, as well as the average diamagnetic shifts of the heme methyls and meso-H, plots of the predicted shifts as a function of axial ligand nodal plane orientation have been constructed for hemin b- and c-containing proteins. Excellent agreement in the order of shifts, and reasonable agreement in the sizes of the observed shifts, is observed in the majority of the ferriheme proteins for which the methyl and meso-H resonances have been assigned and proton shifts reported. Plots have also been constructed for hemin c-containing proteins having the two axial ligand nodal planes oriented at relative angles of 40°, 70°, and 80°. Excellent agreement in the order of shifts, and reasonable agreement in the magnitudes of the observed shifts, is observed in all cases of bacterial cytochromes which do not fit the plots that assume the ligands are in parallel planes, except one – the cytochrome c-552 of Nitrosomonas europae. Except for this case, where the order of the predicted methyl shifts at any angle of the axial ligands disagrees with the observed, the reasons can usually be attributed to a large dihedral angle between two axial ligand nodal planes, to strong H-bonding interactions involving His and/or CN– ligands, or to off-axis binding of one (or both) axial ligand(s). Ruffling of the porphyrin ring may also contribute to the contact shift in as yet undefined ways. Hence, despite the simplicity of the calculations, the agreement with observed data is highly satisfying and the concept of the importance of axial ligand plane orientation on the observed proton shifts of heme proteins is fully confirmed.
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Papers by Undefined Exception