769 research outputs found

    Vicious circles in orthogonal term rewriting systems

    Get PDF
    In this paper we first study the difference between Weak Normalization (WN) and Strong Normalization (SN), in the framework of first order orthogonal rewriting systems. With the help of the Erasure Lemma we establish a Pumping Lemma, yielding information about exceptional terms, defined as terms that are WN but not SN. A corollary is that if an orthogonal TRS is WN, there are no cyclic reductions in finite reduction graphs. This is a stepping stone towards the insight that orthogonal TRSs with the property WN, do not admit cyclic reductions at all

    A Reduction-Preserving Completion for Proving Confluence of Non-Terminating Term Rewriting Systems

    Get PDF
    We give a method to prove confluence of term rewriting systems that contain non-terminating rewrite rules such as commutativity and associativity. Usually, confluence of term rewriting systems containing such rules is proved by treating them as equational term rewriting systems and considering E-critical pairs and/or termination modulo E. In contrast, our method is based solely on usual critical pairs and it also (partially) works even if the system is not terminating modulo E. We first present confluence criteria for term rewriting systems whose rewrite rules can be partitioned into a terminating part and a possibly non-terminating part. We then give a reduction-preserving completion procedure so that the applicability of the criteria is enhanced. In contrast to the well-known Knuth-Bendix completion procedure which preserves the equivalence relation of the system, our completion procedure preserves the reduction relation of the system, by which confluence of the original system is inferred from that of the completed system

    Bleeding Diathesis in Fawn Hooded Rats:Possible Implications for Invasive Procedures and Refinement Strategies

    Get PDF
    The Fawn hooded (FH) rat is commonly used in biomedical research. It is widely acknowledged that the FH rat has a bleeding disorder; leading to abundant bleedings. Although this bleeding disorder is investigated to model the storage pool defect; its impact on commonly performed invasive laboratory procedures has not yet been described. Our research group experienced clinically significant consequences of this bleeding disorder following invasive procedures (including intraperitoneal injections and neurocranial surgery) in the Rjlbm: FH stock. The clinical consequences of the surgical and anesthetic protocols applied; are described including the subsequent procedural refinements applied to minimize the impact of this disorder. It is strongly recommended to take the bleeding diathesis into account when performing invasive procedures in FH rats and to apply the suggested refinement of procedures

    Benzo(a)pyrene induces similar gene expression changes in testis of DNA repair proficient and deficient mice

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Benzo [a]pyrene (B[a]P) exposure induces DNA adducts at all stages of spermatogenesis and in testis, and removal of these lesions is less efficient in nucleotide excision repair deficient <it>Xpc</it><sup>-/- </sup>mice than in wild type mice. In this study, we investigated by using microarray technology whether compromised DNA repair in <it>Xpc</it><sup>-/- </sup>mice may lead to a transcriptional reaction of the testis to cope with increased levels of B[a]P induced DNA damage.</p> <p>Results</p> <p>Two-Way ANOVA revealed only 4 genes differentially expressed between wild type and <it>Xpc</it><sup>-/- </sup>mice, and 984 genes between testes of B[a]P treated and untreated mice irrespective of the mouse genotype. However, the level in which these B[a]P regulated genes are expressed differs between Wt and <it>Xpc</it><sup>-/- </sup>mice (p = 0.000000141), and were predominantly involved in the regulation of cell cycle, translation, chromatin structure and spermatogenesis, indicating a general stress response. In addition, analysis of cell cycle phase dependent gene expression revealed that expression of genes involved in G1-S and G2-M phase arrest was increased after B[a]P exposure in both genotypes. A slightly higher induction of average gene expression was observed at the G2-M checkpoint in <it>Xpc</it><sup>-/- </sup>mice, but this did not reach statistical significance (P = 0.086). Other processes that were expected to have changed by exposure, like apoptosis and DNA repair, were not found to be modulated at the level of gene expression.</p> <p>Conclusion</p> <p>Gene expression in testis of untreated <it>Xpc</it><sup>-/- </sup>and wild type mice were very similar, with only 4 genes differentially expressed. Exposure to benzo(a)pyrene affected the expression of genes that are involved in cell cycle regulation in both genotypes, indicating that the presence of unrepaired DNA damage in testis blocks cell proliferation to protect DNA integrity in both DNA repair proficient and deficient animals.</p

    Exploring the application of a text-to-personality technique in job interviews

    Get PDF
    This research’s purpose was to develop a valid and transparent text-to-personality technique to fit the requirements for personnel selection assessments. In this research we developed an advanced word-counting technique, the HEXACO text-to-personality (HTTP) technique, based on prior lexical personality research to assess personality from job interviews. To evaluate the technique’s construct and criterion-related validity we conducted three studies and analysed the transcripts of asynchronous (n = 102 and 72) and face-to-face (n = 155) interviews. These studies provided four key insights. First, the HTTP technique showed small to medium correlations with self-reported and interviewer-rated personality. Second, the technique showed mixed, but generally favourable, evidence for criterion-related validity. Third, the technique produced a more construct valid personality score when the interview questions activated the predicted personality trait. Fourth, the technique’s additional features (i.e., having weighted keywords and adjusting the keywords’ weight for adjacent quantifiers) did not improve its validity; unit-weighing was approximately equally effective. Altogether, the results show that a word-count text-analysis technique can discover traces of personality in interview transcripts. Still, significant improvements are needed before these types of automatically computed text-to-personality ratings can be used to replace or supplement interviewer ratings

    Нове видання з історії становлення кодикографії та бібліографії стародруків України

    Get PDF
    Розглядається монографічне видання, яке вперше комплексно представ-ляє загальний стан колекційних рукописних та книжкових фондів бібліотек і музеїв в Україні в другій половині ХІХ – 30-х роках ХХ ст.; формування та діяльність наукових центрів з вивчення історії книги в Україні у період, коли археографічна діяльність досягла найвищого рівня свого розвитку.Рассматривается монографическое издание, которое впервые комплексно представляет общее состояние коллекционных рукописных и книжных фондов библиотек и музеев в Украине во второй половине ХіХ – 30-х годах ХХ ст.; формирование и деятельность научных центров по изучению истории книги в Украине в период, когда археографическая деятельность достигла наивысшего уровня своего развития.The consideration of the monographic edition which for the firs time represents in complex the general condition of collection hand-written and book funds of libraries and museums in Ukraine in the second half of ХIХ–30-th years of ХХ century, the formation and activity of scientific centres on studying book history in Ukraine at the period of the highest level of the archaeographic activity development

    Literatuurstudie naar de bepaling van mono- en disacchariden en polyalcoholen met behulp van instrumentale analysemethoden

    Get PDF
    Doel van dit onderzoek was het uitvoeren van een literatuurstudie naar de bepalingsmogelijkheden van mono- en disacchariden en polyalcoholen met behulp van instrumentele analysemethoden

    Ontwikkeling van een gaschromatografische methode voor de bepaling van carvon en limoneen in karwij

    Get PDF
    In het kader van het "Onderzoeksprogramma ter verbetering van karwij als akkerbouwgewas en ter introduktie van nieuwe afzetmogelijkheden" is een gaschromatografische methode ontwikkeld voor de bepaling van carvon en limoneen in karwijzaad
    corecore