A microcomputer system for processing natural languages

This correspondence describes a microcomputer system, called ?BE (for microprocessor-based English), for processing natural languages. Its techniques and facilities, however, should be extendible to other languages. By using the microprocessor as special purpose hardware for several functions of a natural language processor (in particular, hashing and parsing), the system aids computational linguists by increasing the computational power available for natural language investigations. An overview of ?BE is given followed by a more detailed discussion of the hasher and parser. The paper concludes with specific applications of the microprocessor system to computational linguistics. ?BE is not based on a particular theory of language so that the system's user may define his own theory and investigate its consequences. ?BE contains facilities and capabilities to assist such investigations.     

Computed chaining—A hybrid of direct chaining and open addressing

Several popular methods for resolving hashing collisions currently exist: direct chaining, open addressing and pseudochaining. This paper presents a new method for resolving collisions called computed chaining which incorporates features from each of the above methods and in certain situations has advantages over each of them. The computed chaining method is described and a detailed example is provided to assist in its understanding. Included also are experimental results plus a comparison of it with other collision resolution methods.     

A finite element for edge-cracked beam columns

The stiffness matrix is derived for a finite element representing a beam column with rectangular cross section and a single edge crack. The element has zero length, and the standard nodal degrees of freedom associated with beam-column elements. To illustrate its capabilities, the element is used to model propagation of multiple cracks in a self-loaded fixed beam.     

Factors affecting the estimation of physical working capacity at the fatigue threshold

The purpose of this study was to investigate potential improvements in the methodology associated with the Physical Working Capacity at the Fatigue Threshold (PWCFT) test including: (1) the use of a continuous test protocol; (2) the use of a treadmill; (3) the use of a bipolar EMG lead system for noisy electronic environments; and (4) the potential for residual fatigue from tests repeated 24 hours apart. The results of the continuous test protocol (mean +/- S.D. = 210 +/- 73 watts) correlated well (r = 0.856) with the original discontinuous technique (222 +/- 83 watts) and there was no significant (p greater than 0.05) difference between the mean values (t = 1.146). Treadmill testing required a bipolar lead system to counteract the electrical noise generated by the treadmill motor. The heart rate values which corresponded to PWCFT on the treadmill (mean +/- s.d. = 164 +/- b.p.m.) and bicycle ergometer (153 +/- 18 b.p.m.) were highly correlated (r = 0.833) and there was no significant (p greater than 0.05) difference between the mean values (t = 2.22). The use of a bipolar lead EMG system on the bicycle ergometer resulted in significantly (p less than 0.05) smaller voltage for any given power output, and the PWCFT exhibited a low to moderate correlation (r = 0.60) with PWCFT derived from a unipolar arrangement. The test-retest results of discontinuous PWCFT measurements performed 24 hours apart on the bicycle ergometer were correlated at r = 0.812 with no significant (p greater than 0.05) difference (t = 0.52) between the mean values (test = 198 +/- 60; retest = 191 +/- 63 watts).(ABSTRACT TRUNCATED AT 250 WORDS)     

Reply to Levinger's note.

Levinger's extension of the complementary-needs (CN) hypothesis is assessed (see 38: 5867). Although superior to previous CN formulations, it remains a vague statement of faith, lacking theoretical precision and empirical support. The study of needs—complementary or otherwise—is not likely to be fruitful in marriage research. Examples from group dynamics, statistical learning theory, operant theory, personality theory, and phenomenology all demonstrate a general movement in psychology away from the examination of stable traits and motives and toward the use of stimulus situations as predictive constructs. Husbands and wives are spurred to action by stimuli which are not operative in their lives as bartenders and secretaries. Marriage research must specify the stimuli which are specific to spousehood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A study of driver experience and vehicle familiarity in accidents

A separate study was performed as part of a major accident investigation project to (1) test the hypothesis that drivers of vehicles involved in investigated accidents had less driving experience than the general driving population, and (2) test the hypothesis that accident involved drivers were less familiar with their vehicles than the general driving population. A Kolmogorov-Smirnov one-tail test was employed to evaluate the differences in the distributions of driver experience and vehicle familiarity between the “accident sample” and a “control sample.” Results indicated that drivers involved in the investigated accidents had less driving experience in general and had less driving experience with the accident vehicles than drivers in the general population. These effects are discussed briefly and further studies are suggested.     

Pseudouridine synthase 7 impacts Candida albicans rRNA processing and morphological plasticity

RNA can be modified in over 100 distinct ways, and these modifications are critical for function. Pseudouridine synthases catalyse pseudouridylation, one of the most prevalent RNA modifications. Pseudouridine synthase 7 modifies a variety of substrates in Saccharomyces cerevisiae including tRNA, rRNA, snRNA, and mRNA, but the substrates for other budding yeast Pus7 homologues are not known. We used CRISPR-mediated genome editing to disrupt Candida albicans PUS7 and find absence leads to defects in rRNA processing and a decrease in cell surface hydrophobicity. Furthermore, C. albicans Pus7 absence causes temperature sensitivity, defects in filamentation, altered sensitivity to antifungal drugs, and decreased virulence in a wax moth model. In addition, we find C. albicans Pus7 modifies tRNA residues, but does not modify a number of other S. cerevisiae Pus7 substrates. Our data suggests C. albicans Pus7 is important for fungal vigour and may play distinct biological roles than those ascribed to S. cerevisiae Pus7.     

Activating and dominant inactivating c-KIT catalytic domain mutations in distinct clinical forms of human mastocytosis

Human mastocytosis is characterized by increased mast cells. It usually occurs as a sporadic disease that is often transient and limited in children and persistent or progressive in adults. The c-KIT protooncogene encodes KIT, a tyrosine kinase that is the receptor for mast cell growth factor. Because mutated KIT can transform cells, we examined c-KIT in skin lesions of 22 patients with sporadic mastocytosis and 3 patients with familial mastocytosis. All patients with adult sporadic mastocytosis had somatic c-KIT mutations in codon 816 causing substitution of valine for aspartate and spontaneous activation of mast cell growth factor receptor (P = 0.0001). A subset of four pediatric onset cases with clinically unusual disease also had codon 816 activating mutations substituting valine, tyrosine, or phenylalanine for aspartate. Typical pediatric patients lacked 816 mutations, but limited sequencing showed three of six had a novel dominant inactivating mutation substituting lysine for glutamic acid in position 839, the site of a potential salt bridge that is highly conserved in receptor tyrosine kinases. No c-KIT mutations were found in the entire coding region of three patients with familial mastocytosis. We conclude that c-KIT somatic mutations substituting valine in position 816 of KIT are characteristic of sporadic adult mastocytosis and may cause this disease. Similar mutations causing activation of the mast cell growth factor receptor are found in children apparently at risk for extensive or persistent disease. In contrast, typical pediatric mastocytosis patients lack these mutations and may express inactivating c-KIT mutations. Familial mastocytosis, however, may occur in the absence of c-KIT coding mutations.