Showing papers by "Southern Illinois University Carbondale published in 1998"

Impact on Composite Structures

Abstract: 1. Introduction 2. Contact laws 3. Impact dynamics 4. Low velocity impact damage 5. Damage prediction 6. Residual properties 7. Ballistic impact 8. Repairs 9. Impact on sandwich structures References.

Profit, directional distance functions, and Nerlovian efficiency

Abstract: The directional technology distance function is introduced, given an interpretation as a min-max, and compared with other functional representations of the technology including the Shephard input and output distance functions and the McFadden gauge function. A dual correspondence is developed between the directional technology distance function and the profit function, and it is shown that all previous dual correspondences are special cases of this correspondence. We then show how Nerlovian (profit-based) efficiency measures can be computed using the directional technology distance function.

Vagus nerve stimulation therapy for partial-onset seizures A randomized active-control trial

Abstract: Objective: The purpose of this multicenter, add-on, double-blind, randomized, active-control study was to compare the efficacy and safety of presumably therapeutic (high) vagus nerve stimulation with less (low) stimulation. Background: Chronic intermittent left vagus nerve stimulation has been shown in animal models and in preliminary clinical trials to suppress the occurrence of seizures. Methods: Patients had at least six partial-onset seizures over 30 days involving complex partial or secondarily generalized seizures. Concurrent antiepileptic drugs were unaltered. After a 3-month baseline, patients were surgically implanted with stimulating leads coiled around the left vagus nerve and connected to an infraclavicular subcutaneous programmable pacemaker-like generator. After randomization, device initiation, and a 2-week ramp-up period, patients were assessed for seizure counts and safety over 3 months. The primary efficacy variable was the percentage change in total seizure frequency compared with baseline. Results: Patients receiving high stimulation (94 patients, ages 13 to 54 years) had an average 28% reduction in total seizure frequency compared with a 15% reduction in the low stimulation group (102 patients, ages 15 to 60 year; p = 0.04). The high-stimulation group also had greater improvements on global evaluation scores, as rated by a blinded interviewer and the patient. High stimulation was associated with more voice alteration and dyspnea. No changes in physiologic indicators of gastric, cardiac, or pulmonary functions occurred. Conclusions: Vagus nerve stimulation is an effective and safe adjunctive treatment for patients with refractory partial-onset seizures. It represents the advent of a new, nonpharmacologic treatment for epilepsy.

Eyewitness Identification Procedures: Recommendations for Lineups and Photospreads

Abstract: There is increasing evidence that false eyewitness identification is the primary cause of the conviction of innocent people. In 1996, the American Psychology/Law Society and Division 41 of the American Psychological Association appointed a subcommittee to review scientific evidence and make recommendations regarding the best procedures for constructing and conducting lineups and photospreads. Three important themes from the scientific literature relevant to lineup methods were identified and reviewed, namely relative-judgment processes, the lineups-as-experiments analogy, and confidence malleability. Recommendations are made that double-blind lineup testing should be used, that eyewitnesses should be forewarned that the culprit might not be present, that distractors should be selected based on the eyewitness's verbal description of the perpetrator, and that confidence should be assessed and recorded at the time of identification. The potential costs and benefits of these recommendations are discussed.

Organizational Decline and Innovation: A Contingency Framework

Abstract: An examination of the diverse literature on organizational decline shows that there is disagreement regarding the effects of decline on innovation. Some research streams suggest that organizational decline interferes with an organization's capacity to innovate, whereas other research implies just the opposite: organizational decline stimulates innovation. In this article we integrate the inconsistent perspectives and findings in these research streams by developing a contingency model. The model identifies variables at the environmental, organizational, and individual levels of analysis that determine whether organizational decline inhibits or stimulates innovation. We summarize the moderating effects of these variables with empirically testable propositions and discuss implications of the framework for future research and management practice.

Locus Coeruleus Lesions Suppress the Seizure-Attenuating Effects of Vagus Nerve Stimulation

Abstract: Summary: Purpose: Although vagus nerve stimulation (VNS) is now marketed throughout most of the world as a treatment for drug-resistant epilepsy, the therapeutic mechanism of action of VNS-induced seizure suppression has not yet been established. Elucidation of this mechanism is an important first step in the development of strategies to improve VNS efficacy. Because the locus coeruleus (LC) has been implicated in the antinociceptive effects of VNS, we chemically lesioned the LC in the present study to determine if it is a critical structure involved in the anticonvulsant mechanisms of VNS. Methods: Rats were chronically depleted of norepinephrine (NE) by a bilateral infusion of 6-hydroxydopamine (6-OHDA) into the LC. Two weeks later, they were tested with maximal electroshock (MES) to assess VNS-induced seizure suppression. In another experiment, the LC was acutely inactivated with lidocaine, and seizure suppression was tested in a similar fashion. Results: VNS significantly reduced seizure severities of control rats. However, in animals with chronic or acute LC lesions, VNS-induced seizure suppression was attenuated. Conclusions: Our data indicate that the LC is involved in the circuitry necessary for the anticonvulsant effects of VNS. Seizure suppression by VNS may therefore depend on the release of NE, a neuromodulator that has anticonvulsant effects. These data suggest that noradrenergic agonists might enhance VNS-induced seizure suppression.

Humic Substances as a Mediator for Microbially Catalyzed Metal Reduction

Abstract: The potential for humic substances to serve as a terminal electron acceptor in microbial respiration and to function as an electron shuttle between Fe(III)-reducing microorganisms and insoluble Fe(III) oxides was investigated. The Fe(III)-reducing microorganism Geobacter metallireducens conserved energy to support growth from electron transport to humics as evidenced by continued oxidation of acetate to carbon dioxide after as many as nine transfers in a medium with acetate as the electron donor and soil humic acids as the electron acceptor. Growth of G. metallireducens with poorly crystalline Fe(III) oxide as the electron acceptor was greatly stimulated by the addition of as little as 100 μM of the humics analog, anthraquinone-2,6-disulfonate. Other quinones investigated, including lawsone, menadione, and anthraquinone-2-sulfonate, also stimulated Fe(III) oxide reduction. A wide phylogenetic diversity of microorganisms capable of Fe(III) reduction were also able to transfer electrons to humics. Microorganisms which can not reduce Fe(III) could not reduce humics. Humics stimulated the reduction of structural Fe(III) in clay and the crystalline Fe(III) forms, goethite and hematite. These results demonstrate that electron shuttling between Fe(III)-reducing microorganisms and Fe(III) via humics not only accelerates the microbial reduction of poorly crystalline Fe(III) oxide, but also can facilitate the reduction of Fe(III) forms that are not typically reduced by microorganisms in the absence of humics. Addition of humic substances to enhance electron shuttling between Fe(III)-reducing microorganisms and Fe(III) oxides may be a useful strategy to stimulate the remediation of soils and sediments contaminated with organic or metal pollutants. Huminstoffe als Vermittler bei der mikrobiell katalysierten Metallreduktion Es wurde untersucht, inwieweit Huminstoffe als terminale Elektronenakzeptoren bei der mikrobiellen Atmung und als Vermittler bei der Elektronenubertragung zwischen Fe(III)-reduzierenden Mikroorganismen und unloslichen Fe(III)-oxiden fungieren konnen. Das Fe(III)-reduzierende Bakterium Geobacter metallireducens gewinnt Energie zum Wachstum aus der Elektronenubertragung auf Huminstoffe. Das wurde offensichtlich, als nach 9 aufeinanderfolgenden Transfers des Bakteriums auf frisches Medium mit Acetat als Elektronendonor und Boden-Huminstoff als Elektronenakzeptor seine Fahigkeit zur Oxidation von Acetat zu CO2 erhalten blieb. Das Wachstum von G. metallireducens mit niedrigkristallinem Fe(III)-oxid als Elektronenakzeptor konnte durch den Zusatz des Huminstoff-Analogen Anthrachinon-2,6-disulfonat bereits in Konzentrationen von 100 μmol/L deutlich stimuliert werden. Auch weitere untersuchte Chinone wie z.B. Lawson (2-Hydroxy-1,4-naphthochinon), Menadion (2-Methyl-1,4-naphthochinon) und Anthrachinon-2-sulfonat stimulierten die Fe(III)-oxid-Reduktion. Eine grose Anzahl phylogenetisch unterschiedlicher Mikroorganismen, die zur Fe(III)-Reduktion befahigt sind, zeigten gleichzeitig die Fahigkeit zum Elektronentransfer auf Huminstoffe. Zur Fe(III)-Reduktion nicht befahigte Mikroorganismen konnten auch Huminstoffe nicht reduzieren. Durch Huminstoffe konnte die Reduktion von Fe(III) stimuliert werden, das in die Struktur von Tonmineralen und in kristalline Formen des Fe(III)-oxids, Goethit und Hamatit, eingebaut ist. Diese Ergebnisse zeigen, das durch die vermittelnde Funktion der Huminstoffe bei der Elektronenubertragung zwischen Fe(III)-reduzierenden Mikroorganismen und Fe(III) nicht nur die mikrobielle Reduktion von niedrigkristallinem Fe(III)-oxid beschleunigt wird, sondern auch die Reduktion von solchen Formen des Fe(III) erleichtert wird, welche im allgemeinen in Abwesenheit von Huminstoffen durch Fe(III)-reduzierende Mikroorganismen nicht reduziert werden. Die Zugabe von Huminstoffen zur Verbesserung der Elektronenubertragung zwischen Fe(III)-reduzierenden Mikroorganismen und Fe(III)-oxiden konnte eine nutzliche Strategie zur Stimulierung der Sanierung von mit organischen oder metallischen Kontaminanten verunreinigten Boden und Sedimenten sein.

Alcohol Use and Related Consequences Among Students With Varying Levels of Involvement in College Athletics

Abstract: Alcohol use, binge drinking, and substance abuse-related consequences among students with varying levels of participation in intercollegiate athletics were examined. Between October 1994 and May 1996, 51,483 students at 125 institutions answered questions about their involvement in athletics, ranging from noninvolvement to participant to leadership positions, on the long form of the Core Alcohol and Drug Survey. In comparisons with nonathletes, both male and female athletes consumed significantly more alcohol per week, engaged in binge drinking more often, and suffered more adverse consequences from their substance use. No support was found for the hypothesis that athletic leaders were more responsible than other team participants in using alcohol. Male team leaders appeared to be at significantly greater risk than female team leaders; they also consumed more alcohol, binged more often, and suffered more consequences than other team members.

Results of Screening 1.9 Million Texas Newborns for 21-Hydroxylase-Deficient Congenital Adrenal Hyperplasia

Abstract: Objective. To assess results of newborn screening for 21-hydroxylase-deficient congenital adrenal hyperplasia (CAH) in Texas over 6 years of screening 1.9 million infants. Methods. In 1989, CAH was incorporated into the ongoing Texas Newborn Screening Program, which requires two screens on each newborn. 17-Hydroxyprogesterone was assayed, without extraction, by radioimmunoassay of blood collected from heel sticks onto filter paper collection cards. Infants with elevated levels of 17-hydroxyprogesterone were referred for evaluation, and those considered to have CAH were studied with respect to disease characteristics. Data were collected by pediatric endocrinologists using standardized forms that included type of CAH, results of laboratory tests, treatment regimen, disease symptoms and signs, and, for girls, degree of genital virilization. Results. The incidence of classic CAH in Texas is 1:16 008, with a ratio of salt-wasting to simple-virilizing of 2.7:1. A majority of infants detected were undiagnosed until screened, despite signs of salt-wasting or ambiguous genitalia. It was difficult to differentiate salt-wasting from simple-virilizing CAH in infants who were identified before the onset of adrenal insufficiency or electrolyte abnormalities. A substantial number of infants with nonclassic (NC) CAH also were detected. Not all infants were detected on the initial screen; 14% of infants with classic CAH and 87% with NC CAH were detected on the second routine screening test. Conclusions. Our findings confirm the benefits of newborn screening for CAH and the importance of a second screening test, and suggest that programs for newborn CAH screening must consider complex issues in diagnosis and treatment. These results also confirm that CAH is a continuum of disorders, rather than a disorder with discrete subtypes. In addition, the difficulties in differentiating CAH subtypes in newborns, and thus deciding appropriate treatment, and the high incidence of NC CAH suggest that standard diagnostic criteria and treatment regimens for CAH may need modification. Where screening exists, physicians will encounter more cases of CAH than in the past.

Recovery of Humic-Reducing Bacteria from a Diversity of Environments

Abstract: To evaluate which microorganisms might be responsible for microbial reduction of humic substances in sedimentary environments, humic-reducing bacteria were isolated from a variety of sediment types. These included lake sediments, pristine and contaminated wetland sediments, and marine sediments. In each of the sediment types, all of the humic reducers recovered with acetate as the electron donor and the humic substance analog, 2,6-anthraquinone disulfonate (AQDS), as the electron acceptor were members of the family Geobacteraceae. This was true whether the AQDS-reducing bacteria were enriched prior to isolation on solid media or were recovered from the highest positive dilutions of sediments in liquid media. All of the isolates tested not only conserved energy to support growth from acetate oxidation coupled to AQDS reduction but also could oxidize acetate with highly purified soil humic acids as the sole electron acceptor. All of the isolates tested were also able to grow with Fe(III) serving as the sole electron acceptor. This is consistent with previous studies that have suggested that the capacity for Fe(III) reduction is a common feature of all members of the Geobacteraceae. These studies demonstrate that the potential for microbial humic substance reduction can be found in a wide variety of sediment types and suggest that Geobacteraceae species might be important humic-reducing organisms in sediments.

Alcohol use in the Greek system: follow the leader?

Abstract: Objective: This study was designed to identify drinking patterns, consequences of use, and belief systems about alcohol among college students according to their level of involvement in campus fraternity and sorority life. Method: This study of 25,411 (15,100 female) students who completed the Core Alcohol and Drug Survey, from 61 institutions, compared alcohol consumption, binge drinking, consequences of use and beliefs about drinking according to students' level of involvement in fraternities and sororities, ranging from no involvement to that of attending functions only, to active involvement, to leadership positions within Greek organizations. Results: Analyses indicated that students in the Greek system averaged significantly more drinks per week, engaged in heavy drinking more often and, with minor exceptions, suffered more negative consequences than non-Greeks. The leaders of fraternities and sororities consumed alcohol, engaged in heavy drinking and experienced negative consequences at levels at l...

The hyperthermophile chromosomal protein Sac7d sharply kinks DNA

Abstract: The proteins Sac7d and Sso7d belong to a class of small chromosomal proteins from the hyperthermophilic archaeon Sulfolobus acidocaldarius and S. solfactaricus, respectively. These proteins are extremely stable to heat, acid and chemical agents. Sac7d binds to DNA without any particular sequence preference and thereby increases its melting temperature by approximately 40 degrees C. We have now solved and refined the crystal structure of Sac7d in complex with two DNA sequences to high resolution. The structures are examples of a nonspecific DNA-binding protein bound to DNA, and reveal that Sac7d binds in the minor groove, causing a sharp kinking of the DNA helix that is more marked than that induced by any sequence-specific DNA-binding proteins. The kink results from the intercalation of specific hydrophobic side chains of Sac7d into the DNA structure, but without causing any significant distortion of the protein structure relative to the uncomplexed protein in solution.

Uses and gratifications of the World Wide Web: From couch potato to web potato

Abstract: This study investigates uses and gratifications of the World Wide Web and its impact on traditional mass media, especially television. Uses and gratifications of the Word Wide Web are compared to television viewing motivations identified by Rubin (1981, 1983). Principal component analyses identified six Web use motivations: entertainment, social interaction, pass time, escape, information, and Web site preference. Relationships between each use motivation and Web affinity, perceived realism, and ease of use are examined, as is the association between the amount of time spent on the Web and media use. About one‐fourth of all respondents reported spending less time watching television, using their VCR, reading magazines, and reading newspapers since discovering the Web.

A Fixed Point Theorem of Krasnoselskii—Schaefer Type

Abstract: In this paper we focus on three fixed point theorems and an integral equation. Schaefer's fixed point theorem will yield a T-periodic solution of (0.1) x(t)= a(t) + tt-h D(t,s)g(s,x(s))ds if D and g satisfy certain sign conditions independent of their magnitude. A combination of the contraction mapping theorem and Schauder's theorem (known as Krasnoselskii's theorem) will yield a T-periodic solution of (0.2) x(t) = f(t,x(t)) + tt-h D(t,s)g(s,x(s))ds if f defines a contraction and if D and g are small enough. We prove a fixed point theorem which is a combination of the contraction mapping theorem and Schaefer's theorem which yields a T-periodic solution of (0.2) when / defines a contraction mapping, while D and g satisfy the aforementioned sign conditions.

“To dryness and beyond” – Preparation for the dried state and rehydration in vegetative desiccation-tolerant plants

Abstract: The ability of vegetative plant tissues to survive desiccation is an uncommon trait, although plants that are able to do this represent all major classes of plants Two classes of vegetative desiccation-tolerant plants exist; those that are modified desiccation-tolerant and can only survive desiccation if drying rates are slow, and those that are fully desiccation-tolerant and can survive even rapid drying rates Investigations into the cellular level responses of these two types of plants has lead to an understanding of the underlying mechanisms of desiccation-tolerance The following proposed mechanisms for desiccation-tolerance are presented Modified desiccation-tolerant plants utilize inducible cellular protection systems supplemented in part by a minor rehydration induced repair component Fully desiccation-tolerant plants utilize a rehydration induced repair system that is complemented by a constitutive protection component This minireview explores the evidence for these proposed mechanisms in an attempt to lay the theoretical ground work for future work in this area

A New Approach to the Study of Ticket Splitting

Abstract: A new solution to the ecological inference problem is used to examine split-ticket voting patterns across states and congressional districts in the 1988 elections. Earlier studies of ticket splitting used either aggregate data, which suffer from the “ecological fallacy” and threaten individual-level inferences, or survey data from small, unrepresentative samples. We produce more accurate estimates of the proportions of voters splitting their ballots in each state and district, which enables us to examine variations across geographical units. We also clarify the connection between ticket splitting and divided government and test several competing theories about the causes of both. We find, contrary to balancing arguments, that voters are not intentionally splitting tickets to produce divided government and moderate policies. In most cases split outcomes are a by-product of lopsided congressional campaigns that feature well-funded, high-quality candidates versus unknown competitors.

The expression of the KAI1 gene, a tumor metastasis suppressor, is directly activated by p53

Abstract: KAI1 is a tumor metastasis suppressor gene that is capable of inhibiting the metastatic process in animals. The expression of the KAI1 gene also is found to be down-regulated during the tumor progression of prostate, breast, lung, bladder, and pancreatic cancers in humans, and this down-regulation appears to be at or posttranscription level. We have found that the tumor suppressor gene p53 can directly activate the KAI1 gene by interacting with the 5′ upstream region. The p53 responding region is located at approximately 860 bases upstream of the transcriptional initiation site, and it contains a typical tandem repeat of the p53 consensus-binding sequence. A gel-shift mobility analysis showed that this sequence indeed had the ability to bind to the purified p53 protein. Mutations of this sequence abolished the responsiveness to p53 and also the binding ability to the p53 protein. Furthermore, immunohistochemical analysis of 177 samples of human prostate tumors revealed that the expression of the KAI1 gene was correlated strongly to that of the p53 gene and that the loss of these two markers resulted in poor survivals of patients. Our data indicate a direct relationship between p53 and KAI1 genes and suggest that the loss of p53 function, which is commonly observed in many types of cancer, leads to the down-regulation of the KAI1 gene, which may result in the progression of metastasis.

The crystal structure of the hyperthermophile chromosomal protein Sso7d bound to DNA

Abstract: Sso7d and Sac7d are two small (~7,000 Mr), but abundant, chromosomal proteins from the hyperthermophilic archaeabacteria Sulfolobus solfataricus and S. acidocaldarius respectively. These proteins have high thermal, acid and chemical stability. They bind DNA without marked sequence preference and increase the Tm of DNA by ~40 °C. Sso7d in complex with GTAATTAC and GCGT(iU)CGC + GCGAACGC was crystallized in different crystal lattices and the crystal structures were solved at high resolution. Sso7d binds in the minor groove of DNA and causes a single-step sharp kink in DNA (~60°) by the intercalation of the hydrophobic side chains of Val 26 and Met 29. The intercalation sites are different in the two complexes. Observations of this novel DNA binding mode in three independent crystal lattices indicate that it is not a function of crystal packing.

Stochastic Differential Systems With Memory: Theory, Examples and Applications

Abstract: The purpose of this article is to introduce the reader to certain aspects of stochastic differential systems whose evolution depends on the past history of the state

Population Biology of Grasses

Abstract: Contributors Preface Darwin revisited: approaches to the ecological study of grasses A. D. Bradshaw Part I. Population Variation and Life History Patterns: 1. Allozyme diversity in the grasses M. J. W. Godt and J. L. Hamrick 2. Ecology of seed dormancy and germination in grasses C. C. Baskin and J. M. Baskin 3. Seed dispersal and seedling establishment in grass populations G. P. Cheplick 4. Clonal biology of caespitose grasses D. D. Briske and J. D. Derner 5. Ecological aspects of sex expression in grasses J. A. Quinn 6. Interspecific variation in plasticity of grasses in response to nitrogen supply E. Garnier 7. Population biology of intraspecific polyploidy in grasses K. H. Keeler Part II. Ecological Interactions 8. Plant-plant interactions in grasses and grasslands W. K. Lauenroth and M. O. Aguilera 9. Competition between grasses and woody plants S. D. Wilson 10. Fungal endophyte infection and the population dynamics of grasses K. Clay 11. Arbuscular mycorrhizas and the population biology of grasses K. K. Newsham and A. R. Watkinson Part III. Population Biology of Specific Groups: 12. Population dynamics in the regeneration process of monocarpic dwarf bamboos, Sasa species A. Makita 13. Population dynamics of perennial grasses in African savanna and grassland T. G. O'Connor and T. M. Everson 14. A life cycle approach to the population ecology of two tropical grasses in Queensland, Australia D. M. Orr Index.

A Novel Fermentation Pathway in an Escherichia coli Mutant Producing Succinic Acid, Acetic Acid, and Ethanol

Abstract: Escherichia coli strain NZN111, which is unable to grow fermentatively because of insertional inactivation of the genes encoding pyruvate: formate lyase and the fermentative lactate dehydrogenase, gave rise spontaneously to a chromosomal mutation that restored its ability to ferment glucose. The mutant strain, named AFP111, fermented glucose more slowly than did its wild-type ancestor, strain W1485, and generated a very different spectrum of products. AFP111 produced succinic acid, acetic acid, and ethanol in proportions of approx 2:1:1. Calculations of carbon and electron balances accounted fully for the observed products; 1 mol of glucose was converted to 1 mol of succinic acid and 0.5 mol each of acetic acid and ethanol. The data support the emergence in E. coli of a novel succinic acid:acetic acid:ethanol fermentation pathway.

Assessing the Suitability of Landscapes for Northern Bobwhite

Abstract: Widespread declines of northern bobwhite (Colinus virginianus) populations may reflect habitat alteration at both site and landscape level. To investigate the latter, we quantified landscape composition and pattern throughout Illinois (>145,900 km 2 ) using classified satellite imagery and FRAGSTATS software. We then compared landscape structure with indexes of northern bobwhite abundance using county-level harvest and North American Breeding Bird Survey (BBS) data. Analyses at both scales suggested bobwhite were primarily associated with diverse, patchy landscapes that contained moderate amounts of grassland and row crops and abundant woody edge. These findings were used to develop a PATREC model to identify and map Illinois landscapes potentially suitable for bobwhite. Whether or not such areas actually support good bobwhite populations depends upon site conditions generally not discernable by remote sensing. Nevertheless, knowledge of the extent and distribution of potentially suitable landscapes can enhance and focus management efforts.

Some Ideological Foundations of Organizational Downsizing

Abstract: This article explores the ideological foundations of organizational downsizing in the 1990s and focuses on the ideology of employee self-reliance and the ideology of debureaucratization. We document these two managerial ideologies by examining business press articles and popular management literature in which they are being promulgated. Based on past organizational research that has traced the effects of ideologies on organizations, we argue that these two ideologies increase the likelihood of downsizing. This theoretical framework is developed, and its implications for future research, management practice, and government policy are discussed.

The Public’s Conditional Response to Supreme Court Decisions

Abstract: To investigate the effect of the Supreme Court on public opinion, we offer the conditional response hypothesis based on a theory of Supreme Court legitimacy and a microlevel social-psychological theory of attitude formation. Together these theories predict that the Court may affect public opinion when it initially rules on a salient issue, but that subsequent decisions on the same issue will have little influence on opinion. To test our predictions, we analyze public opinion data before and after the Supreme Court ruled in a highly visible abortion case (Webster v. Reproductive Health Services [1989]) and before and after three key capital punishment rulings (Furman v. Georgia [1972], Gregg v. Georgia [1976], and McCleskey v. Kemp [1987]). The results suggest that our theory is not issue bound but is generally applicable to how the Supreme Court affects public opinion when it rules in highly salient cases.