Showing papers by "University of Texas at Dallas published in 1981"

Immunohistochemical studies on the effect of capsaicin on spinal and medullary peptide and monoamine neurons using antisera to substance P, gastrin/CCK, somatostatin, VIP, enkephalin, neurotensin and 5-hydroxytryptamine.

Abstract: After neonatal treatment of rats with capsaicin, the spinal cord, the spinal trigeminal nucleus and spinal and trigeminal ganglia were analysed with immunohistochemistry using antisera to several peptides and 5-hydroxytryptamine. A marked decrease was observed in substance P-, cholecystokinin-, somatostatin- and VIP-like immunoreactivity present in the central branches of primary sensory neurons in the spinal cord and in substance P- and somatostatin-like immunoreactivity in sensory ganglion cells. No definite depleting effect of capsaicin could be established on 5-hydroxytryptamine and peptides, such as enkephalin and neurotensin, present in centrally originating fibres in the dorsal horn of the spinal cord. The results demonstrate that the effects of capsaicin are not confined to substance P immunoreactive primary sensory neurons. The possibility is discussed that capsaicin effects specifically functioning rather than chemically specific primary sensory neurons.

Near‐uv radiation effects on microorganisms

Abstract: This review covers effects in microorganisms produced primarily by near-ultraviolet radiation (near UV), or by radiation referred to as ‘UV-A’ (32HOO nm). Effects occurring only at shorter wavelengths. in the ‘mid UV’ or ‘UV-B’ (29Ck320nm) are often not considered. since the mechanisms of action in the UV-B region are more similar to those produced by far-UV or ‘UV-c‘ radiation (2W290 nm). Yearly Reviews. in June 1976 by Jagger [21]. in December 1977 by Thomas [58] and in a review restricted to physiological effects in June 1979 by Fraikin and Rubin [13]. The present review attempts to cover the literature from January 1978 through June 1981 that is not covered in the Fraikin and Rubin review. For purposes of continuity, of course, sope references will date further back Extensive reviews in Photochemical and Photohiologicul Recirws of lethal and mutagenic effects appeared in Vol. 2 [74]. and of physiological effects will appear in Vol. 7 1233.

Predicting turnover: a comparison of part-time and full-time employees

Abstract: The predictability of turnover was compared for part-time versus full-time workers. This was accomplished using variables (1) that were hypothesized by Mobley (1977) to precede the turnover decision and (2) that have been shown in previous research to be significantly related to turnover. Measures of these variables were assessed via questionnaires following the second month of employment. Turnover was assessed directly from company records for a period of up to twelve months following employment. None of the hypothesized antecedent variables were significantly related to turnover within the part-time group. However, within the full-time group, all of the hypothesized precursors to turnover were found to be at least marginally related to actual turnover. Further, there was evidence to suggest differential predictability of turnover across full-time and part-time employment status groups, suggesting that the two groups may have a different ‘psychology of work’. These results are discussed in terms of the supportive evidence provided.

Location on Tree Networks: P-Centre and n-Dispersion Problems

Abstract: We consider two problems of locating facilities on trees. In the first, we wish to determine the location of n points so as to maximize the minimum distance between any pair. In the second we wish to locate p centers of a single type of facility so as to minimize the maximum distance between any point and the center nearest to it. We provide polynomial algorithms for both problems, of O|N|2 log n · log |N| for the first problem and of O|N|2 log p for the second, where |N| is the number of nodes in the tree.

Sequence dependence of the circular dichroism of synthetic double‐stranded RNAs

Abstract: We have synthesized and studied the CD spectra of five new double-stranded RNA polymers: poly[r(A-G)·r(C-U)], poly[r(A-U-C)·r(G-A-U)], poly[r(A-C-U)·r(A-G-U)], poly[r(A-A-C)·r(G-U-U)], and poly[r(A-C-C)·r(G-G-U)]. Together with previously published spectra of seven other RNA sequences, the spectra of these new sequences provide a library sufficient to approximate the spectra of all other RNA sequences by first-neighbor formulas and, in addition, give four spectra with which we may test the validity of first-neighbor approximations. (1) We find that the spectra of RNA sequence isomers are very different, but that the spectra essentially do obey first-neighbor relationships. (2) We have derived tentative first-neighbor assignments of negative bands at about 295 and 210 nm in the CD spectra. (3) A test of spectral independence shows that among the 12 polymer spectra there are at least seven significant independent spectral shapes, one less than the eight needed to give the most accurate spectral analysis of an unknown RNA sequence for its first-neighbor frequencies. (4) Spectra are calculated for RNAs of random base composition, approximating natural RNAs having complex sequences. (5) A T-matrix of spectral components assigned to the first-neighbor base pairs is derived from 10 of the spectra. This matrix allows an estimation of the CD spectrum of any other known RNA sequence or an analysis of the spectrum of an unknown sequence for its distribution of first-neighbor base-pair frequencies. (6) Test analyses of two of the synthetic polymers and of two natural RNAs set a probable limit on the accuracy of first-neighbor frequency determinations using this T-matrix. (7) Finally, we summarize in an appendix the melting temperatures for all the RNA and corresponding DNA sequences; it appears that the Tm values of both DNAs and RNAs approximately obey first-neighbor relationships.

Conjugal Work Roles and Marital Solidarity

Abstract: WE propose a role homophily theory which posits that marriages are enhanced when spouses' roles are similar. We use cross-sectional survey data to determine how respondents' marital solidarity is affected by whether wives are employed, and by the occupationally derived socioeconomic status of both husbands and wives. We find that wives' employment has a positive effect on marital solidarity as perceived by both husbands and wives. This finding is consistent with role homophily theory, but inconsistent with the predictions of both sex-role differentiation and bargaining theories. When we examine effects of husbands' and wives' socioeconomic status on marital solidarity we find little support for any of the three theories. We conclude that role homophily theory is the best supported of the three theories.

Determinants of organizational commitment in working women: Some implications for organizational integration

Abstract: This study proposed and examined determinants of organizational commitment in working women. Among the selected determinants of role stress, personal characteristics, and satisfaction with various aspects of the organization, satisfaction with promotional opportunities was die best predictor of commitment. Experienced role stress was the second best determinant, although the observed relationship was inverse. Other variables such as age, education, and need for achievement, found to be antecedents of organizational commitment in earlier empirical studies, failed to predict commitment in this heterogeneous sample of working women. Findings were discussed in terms of the implications for further research and theory development in the area of organizational commitment as well as for the integration of women into modern work organizations.

Cis-platinum vestibular toxicity.

Abstract: Cis-diamminedichloroplatinum has been proven to be an effective neoplastic agent. Nephrotoxicity and ototoxicity are two prominent side effects of this drug. Investigation of ototoxicity has been limited to auditory function. This report details the first known case of vestibular toxicity following platinum therapy. In addition, a prospective vestibular testing program is reported.

Photolytic spectroscopy of simple molecules. II. The production of 6P atoms from the X 1Σg state of Cs2

Abstract: In this work the two‐photon technique for the study of selective photolysis described in the preceding article was used for the measurement of the relative cross sections for the photolysis of Cs2 into each of the energetically possible product channels that could have been reached at wavelengths in the range from 445 to 640 nm. The resulting dispersion curves showed three relatively broad absorption bands, each leading to a different distribution of population among the product states. A relatively broad band in the blue region of the spectrum was found to yield an inverted branching ratio for dissociation which favored the more highly excited product by a factor of better than 50 to 1. This particular result implied that continuous wave, stimulated emission should be obtained from the 5 2D3/2→6 2P1/2 transition of atomic cesium with adequate photolytic pumping of Cs2 at blue wavelengths. An analysis of the complete photolysis spectrum obtained in this work indicated that both dissociation and predissoci...

Capture-Recapture Sampling for Estimating Software Error Content

Abstract: Mills capture-recapture sampling method allows the estimation of the number of errors in a program by randomly inserting known errors and then testing the program for both inserted and indigenous errors This correspondence shows how correct confidence limits and maximum likelihood estimates can be obtained from the test results Both fixed sample size testing and sequential testing are considered

Inducible repair of near-UV radiation lethal damage in E. coli.

Abstract: We present here the initial characterization of a new repair system which is induced in actively growing cultures of Escherichia coli and which repairs a major fraction of lethal damage produced by near-UV (310–400 nm) light. This system is different from the error-prone ‘SOS’ repair system for DNA,known to be induced in E. coli by treatments which damage DNA and/or inhibit DNA replication, such as irradiation by far-UV (254 nm) light or X rays, thymine starvation or treatment with naladixic acid or mitomycin C1,2. The SOS response requires induction of an ‘X’ protein3, the product of the recA gene4–6, whereas the inducible repair system described here utilizes proteins distinct from the X protein.

Estimating Volumes of Remaining Fossil Fuel Resources: A Critical Review

Abstract: A number of problems arise in applying standard statistical techniques to the estimation of remaining volumes of crude oil and natural gas resources. This article reviews and criticizes past approaches, which include methods based on geology and methods that are primarily statistical in nature. Two newer approaches to the problem are described and their results summarized. It is clear that more statistical work is needed in this area.

Photolytic spectroscopy of simple molecules. I. The production of 5 2D atoms from Cs2

Abstract: A two‐photon technique is reported for the measurement of relative cross sections for the selective photolysis of simple molecules into particular product channels. In a demonstration of this method two independently tunable dye lasers were used to sequentially dissociate molecules of Cs2 for wavelengths in the visible range and then to excite the resulting products to Rydberg states which could be readily ionized for detection. With this system the spectra were determined for the selective photolysis of Cs2 into product atoms in the 5 2D3/2 and 5 2D5/2 states. Two relatively broad absorption bands were found, each of which led to the preferential population of a different fine structure components of the 5 2D products. Analysis of the photolysis spectra indicated that both dissociation and predissociation mechanisms were responsible and led to the identification of a new 1Σu and 3Σu state correlated with the 5 2D atomic states.

Bandwidth constrained NP-Complete problems

Abstract: Bandwidth restrictions are considered on several NP-Complete problems, including the following problems: (1) 3-Satisfiability, (2) Independent Set and Vertex Cover, (3) Simple Max Cut (4) Partition into Triangles, (5) 3-Dimensional Matching, (6) Exact Cover by 3 Sets, (7) Dominating Set, (8) Graph Grundy Numbering (for graphs of finite degree), (9) 3-Colorability, (10) Directed and Undirected Hamiltonian Circuit, (11) Bandwidth Minimization, and (12) Feedback Vertex Set and Feedback Arc Set. It is shown that each of the problems (1)-(12) when restricted to graphs (formulas, triples, or sets) of bandwidth bounded by a function f is log space hard for the complexity class NTISP (poly,f(n)). (NTISP(poly,f(n)) denotes the family of problems solvable nondeterministically in polynomial time and simultaneous f(n) space, e.g., NTISP(poly,poly) = NP and NTISP(poly, log n) = NSPACE(log n).). In fact, (1)-(9) are log space complete for NTISP(poly,f(n)) when the bandwidth is bounded by the function f. This means, for example, that (1)-(9) provide several new examples of problems complete for NSPACE(log n), and hence solvable in polynomial time deterministically, when restricted to bandwidth log2n. In general, for a function f, if any of the problems (1)-(12), when restricted to bandwidth f(n), could be solved deterministically in polynomial time, then NTISP(poly, f(n))

Polynomial algorithms for a class of linear programs

Abstract: This paper describes several algorithms for solution of linear programs. The algorithms are polynomial when the problem data satisfy certain conditions.

The Ages of Men and Women in Magazine Advertisements

Abstract: ferences between control and cue panels remained in the 1978 data. The implications of these findings for FCC policy seem clear. Of course, there is a n alternative to a recognition again in FCC regulations that the network news necessarily is programming where time is of special significance. This alternative would be to begin, as CBS News recently has done, a West Coast edition of network evening news programs.

The impact of reprography on the copyright system

Abstract: This is a report performed for the Canadian government in 1981 on the impact of copying (photocopying) on copyright holders. As far as I know, it was the first theoretical claim that copying might not hurt copyright holders, and might even benefit them, due to the concept of indirect appropriability. Although some of this material later appeared in articles in the JPE and AER, this is a more complete treatment focused on the copying issue. This report proposes a fairly simple model to explain what happens in markets where copying occurs. The key parameters turn out to be the variability in the number of copies made from each original, the degree of substitutability between the original and the copy, and whether or not the copyright holder can engage in price discrimination. Anyone interested in the issue of copying in the Internet era, or who wants to and be able to analyze behavior such as that associated with Napster, will want to read this.

The roles of the rel+ gene and of 4-thiouridine in killing and photoprotection of Escherichia coli by near-ultraviolet radiation.

Abstract: — Photoprotection is a reduction in response to far-UV (190–300. nm) radiation in cells that have been previously exposed to longer wavelengths. It has been proposed that photoprotection operates by means of a growth delay that permits more time for dark repair. Growth delay in Escherichia coli utilizes 4-thiouridine (4Srd) in transfer RNA as a chromophore and it requires the rel+ gene, which exerts a stringent control upon RNA synthesis. Mutants that were either rel or 4Srd− were isolated from E. coli B, utilizing a near-UV-induced growth-delay selection technique. The rel mutants, which undergo little growth delay after near-UV irradiation, show only 50% as much photoprotection as wild types, while 4Srd− mutants show no photoprotection at all. Thus, photoprotection appears to utilize 4Srd as its sole chromophore in E. coli B and B/r, and no more than 50% of photoprotection in these strains can be a result of near-UV-induced growth delay.