Texas Christian University

About: Texas Christian University is a education organization based out in Fort Worth, Texas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 3245 authors who have published 8258 publications receiving 282216 citations. The organization is also known as: TCU & Texas Christian University, TCU.

Vocabulary Knowledge of Children With Cochlear Implants: A Meta-Analysis.

Abstract: This article employs meta-analysis procedures to evaluate whether children with cochlear implants demonstrate lower spoken-language vocabulary knowledge than peers with normal hearing. Of the 754 articles screened and 52 articles coded, 12 articles met predetermined inclusion criteria (with an additional 5 included for one analysis). Effect sizes were calculated for relevant studies and forest plots were used to compare differences between groups of children with normal hearing and children with cochlear implants. Weighted effect size averages for expressive vocabulary measures (g = -11.99; p < .001) and for receptive vocabulary measures (g = -20.33; p < .001) indicated that children with cochlear implants demonstrate lower vocabulary knowledge than children with normal hearing. Additional analyses confirmed the value of comparing vocabulary knowledge of children with hearing loss to a tightly matched (e.g., socioeconomic status-matched) sample. Age of implantation, duration of implantation, and chronological age at testing were not significantly related to magnitude of weighted effect size. Findings from this analysis represent a first step toward resolving discrepancies in the vocabulary knowledge literature.

Microcosm experiments have limited relevance for community and ecosystem ecology: comment

Abstract: In a recent article, Carpenter (1996) suggested that microcosm experiments are disconnected from natural lake systems and concluded that microcosms have limited relevance for community and ecosystem ecology of lakes. Carpenter also chastised academic ecologists for using microcosms for graduate training in aquatic ecology. We feel Carpenter's comments misrepresent microcosm experiments and their contributions to aquatic ecology. The purpose of this comment is to present an alternative view of the role of microcosm experiments for both research and graduate education in aquatic ecology. We argue that there is little information supporting Carpenter's (1996) suggestion that microcosms are disconnected from natural lake systems. Instead we suggest that microcosm and wholelake experiments have revealed similar community responses to major factors regulating lake communities such as nutrients and planktivorous fish. We conclude that no one type of research approach will provide a complete understanding of how lake systems function and that most rapid research progress can be made through the complementary use of microcosms and whole-lake experiments coupled with modeling and long-term observational studies. Carpenter (1996:678) stated that "the size and duration of microcosm experiments exclude or distort important features of communities and ecosystems" and that some "processes and organisms change so rapidly that they can reach unrealistic rates or population densities in the course of microcosm experiments." To support his argument that "limnology provides many examples of disconnection between microcosms and natural systems," Carpenter cited papers by Gerhart and Likens (1975), Stephenson et al. (1984), Bloesch

Coinfections of the Respiratory Tract: Viral Competition for Resources.

Abstract: Studies have shown that simultaneous infection of the respiratory tract with at least two viruses is common in hospitalized patients, although it is not clear whether these infections are more or less severe than single virus infections. We use a mathematical model to study the dynamics of viral coinfection of the respiratory tract in an effort to understand the kinetics of these infections. Specifically, we use our model to investigate coinfections of influenza, respiratory syncytial virus, rhinovirus, parainfluenza virus, and human metapneumovirus. Our study shows that during coinfections, one virus can block another simply by being the first to infect the available host cells; there is no need for viral interference through immune response interactions. We use the model to calculate the duration of detectable coinfection and examine how it varies as initial viral dose and time of infection are varied. We find that rhinovirus, the fastest-growing virus, reduces replication of the remaining viruses during a coinfection, while parainfluenza virus, the slowest-growing virus is suppressed in the presence of other viruses.

Legal Pressure and Treatment Retention in a National Sample of Long-Term Residential Programs

Abstract: This study examined the association between legal pressure and treatment retention in a national sample of 2,605 clients admitted to 18 long-term residential facilities that participated in the Drug Abuse Treatment Outcome Study (DATOS). Hierarchical linear models were used to assess the relationship of background factors and legal pressure with treatment participation for 90 days or longer. Two thirds of the sample entered residential treatment with moderate to high pressure from legal authorities, and they were significantly more likely than the low-pressure clients to stay 90 days or more. Moreover, the difference in retention between moderate-to-high-and low-pressure clients was even greater in programs with proportionally larger caseloads under legal surveillance. The criminal justice system (CJS) can influence treatment participation and retention, and it appears essential for the CJS and treatment programs to maintain an open and constructive relationship to maximize their potential combined impact.

Customer-Base Concentration, Profitability, and the Relationship Life Cycle

Abstract: Using a recently expanded dataset on supplier-customer links, we introduce a dynamic relationship life-cycle hypothesis. We hypothesize that the relation between customer-base concentration and profitability is significantly negative in the early years of the relationship, but becomes positive as the relationship matures. The key driver of this dynamic is the customer-specific investments that the relationship entails. These investments result in larger fixed costs, greater operating leverage, and a higher probability of losses early in the relationship, but can significantly benefit the firm as the relationship matures. Although many of these money-losing firms in early-stage relationships were not studied in Patatoukas (2012), we find a market reaction to increases in customer concentration similar to that in his paper. This result provides powerful confirmatory evidence of the value of customer concentration. We document one of the intangible benefits of customer concentration, technology sha...