Showing papers by "University of Kansas published in 2009"

Eutrophication science: where do we go from here?

Abstract: Cultural eutrophication has become the primary water quality issue for most of the freshwater and coastal marine ecosystems in the world. However, despite extensive research during the past four to five decades, many key questions in eutrophication science remain unanswered. Much is yet to be understood concerning the interactions that can occur between nutrients and ecosystem stability: whether they are stable or not, alternate states pose important complexities for the management of aquatic resources. Evidence is also mounting rapidly that nutrients strongly influence the fate and effects of other non-nutrient contaminants, including pathogens. In addition, it will be important to resolve ongoing debates about the optimal design of nutrient loading controls as a water quality management strategy for estuarine and coastal marine ecosystems.

Radiofrequency Ablation in Barrett's Esophagus with Dysplasia

Abstract: Background Barrett’s esophagus, a condition of intestinal metaplasia of the esophagus, is associated with an increased risk of esophageal adenocarcinoma. We assessed whether endoscopic radiofrequency ablation could eradicate dysplastic Barrett’s esophagus and decrease the rate of neoplastic progression. Methods In a multicenter, sham-controlled trial, we randomly assigned 127 patients with dysplastic Barrett’s esophagus in a 2:1 ratio to receive either radiofrequency ablation (ablation group) or a sham procedure (control group). Randomization was stratified according to the grade of dysplasia and the length of Barrett’s esophagus. Primary outcomes at 12 months included the complete eradication of dysplasia and intestinal metaplasia. Results In the intention-to-treat analyses, among patients with low-grade dysplasia, complete eradication of dysplasia occurred in 90.5% of those in the ablation group, as compared with 22.7% of those in the control group (P<0.001). Among patients with highgrade dysplasia, complete eradication occurred in 81.0% of those in the ablation group, as compared with 19.0% of those in the control group (P<0.001). Overall, 77.4% of patients in the ablation group had complete eradication of intestinal metaplasia, as compared with 2.3% of those in the control group (P<0.001). Patients in the ablation group had less disease progression (3.6% vs. 16.3%, P = 0.03) and fewer cancers (1.2% vs. 9.3%, P = 0.045). Patients reported having more chest pain after the ablation procedure than after the sham procedure. In the ablation group, one patient had upper gastrointestinal hemorrhage, and five patients (6.0%) had esophageal stricture. Conclusions In patients with dysplastic Barrett’s esophagus, radiofrequency ablation was associated with a high rate of complete eradication of both dysplasia and intestinal metaplasia and a reduced risk of disease progression. (ClinicalTrials.gov number, NCT00282672.)

Bilateral Deep Brain Stimulation vs Best Medical Therapy for Patients With Advanced Parkinson Disease: A Randomized Controlled Trial

Abstract: Context Deep brain stimulation is an accepted treatment for advanced Parkinson disease (PD), although there are few randomized trials comparing treatments, and most studies exclude older patients. Objective To compare 6-month outcomes for patients with PD who received deep brain stimulation or best medical therapy. Design, Setting, and Patients Randomized controlled trial of patients who received either deep brain stimulation or best medical therapy, stratified by study site and patient age ( Intervention Bilateral deep brain stimulation of the subthalamic nucleus (n = 60) or globus pallidus (n = 61). Patients receiving best medical therapy (n = 134) were actively managed by movement disorder neurologists. Main Outcome Measures The primary outcome was time spent in the “on” state (good motor control with unimpeded motor function) without troubling dyskinesia, using motor diaries. Other outcomes included motor function, quality of life, neurocognitive function, and adverse events. Results Patients who received deep brain stimulation gained a mean of 4.6 h/d of on time without troubling dyskinesia compared with 0 h/d for patients who received best medical therapy (between group mean difference, 4.5 h/d [95% CI, 3.7-5.4 h/d]; P Conclusion In this randomized controlled trial of patients with advanced PD, deep brain stimulation was more effective than best medical therapy in improving on time without troubling dyskinesias, motor function, and quality of life at 6 months, but was associated with an increased risk of serious adverse events. Trial Registration clinicaltrials.gov Identifier: NCT00056563

Improving the Quality of Spiritual Care as a Dimension of Palliative Care: The Report of the Consensus Conference

Abstract: A Consensus Conference sponsored by the Archstone Foundation of Long Beach, California, was held February 17–18, 2009, in Pasadena, California. The Conference was based on the belief that spiritual care is a fundamental component of quality palliative care. This document and the conference recommendations it includes builds upon prior literature, the National Consensus Project Guidelines, and the National Quality Forum Preferred Practices and Conference proceedings.

Niches and distributional areas: Concepts, methods, and assumptions

Abstract: Estimating actual and potential areas of distribution of species via ecological niche modeling has become a very active field of research, yet important conceptual issues in this field remain confused. We argue that conceptual clarity is enhanced by adopting restricted definitions of “niche” that enable operational definitions of basic concepts like fundamental, potential, and realized niches and potential and actual distributional areas. We apply these definitions to the question of niche conservatism, addressing what it is that is conserved and showing with a quantitative example how niche change can be measured. In this example, we display the extremely irregular structure of niche space, arguing that it is an important factor in understanding niche evolution. Many cases of apparently successful models of distributions ignore biotic factors: we suggest explanations to account for this paradox. Finally, relating the probability of observing a species to ecological factors, we address the issue of what objects are actually calculated by different niche modeling algorithms and stress the fact that methods that use only presence data calculate very different quantities than methods that use absence data. We conclude that the results of niche modeling exercises can be interpreted much better if the ecological and mathematical assumptions of the modeling process are made explicit.

Optimism and Physical Health: A Meta-analytic Review

Abstract: Background Prior research links optimism to physical health, but the strength of the association has not been systematically evaluated.

Kirby-Bauer Disk Diffusion Susceptibility Test Protocol

Abstract: Protocol for using the Kirby-Bauer disk diffusion susceptibility test in the microbiology lab.

Mediation models for longitudinal data in developmental research.

Abstract: Mediation models are used to describe the mechanism(s) by which one variable influences another. These models can be useful in developmental research to explicate the relationship between variables, developmental processes, or combinations of variables and processes. In this article we describe aspects of mediation effects specific to developmental research. We focus on three central issues in longitudinal mediation models: the theory of change for variables in the model, the role of time in the model, and the types of indirect effects in the model. We use these themes as we describe three different models for examining mediation in longitudinal data.

International patterns and trends in thyroid cancer incidence, 1973–2002

Abstract: During the past several decades, an increasing incidence of thyroid cancer has been reported in many parts of the world. To date, no study has compared the trends in thyroid cancer incidence across continents. We examined incidence data from cancer incidence in five continents (CI5) over the 30-year period 1973-2002 from 19 populations in the Americas, Asia, Europe, and Oceania. Thyroid cancer rates have increased from 1973-1977 to 1998-2002 for most of the populations except Sweden, in which the incidence rates decreased about 18% for both males and females. The average increase was 48.0% among males and 66.7% among females. More recently, the age-adjusted international thyroid cancer incidence rates from 1998 to 2002 varied 5-fold for males and nearly 10-fold for females by geographic region. Considerable variation in thyroid cancer incidence was present for every continent but Africa, in which the incidence rates were generally low. Our analysis of published CI5 data suggests that thyroid cancer rates increased between 1973 and 2002 in most populations worldwide, and that the increase does not appear to be restricted to a particular region of the world or by the underlying rates of thyroid cancer.

Detection of functional haematopoietic stem cell niche using real-time imaging

Abstract: Haematopoietic stem cells are found in a specialized regulatory environment or niche in bone marrow. The precise location and characteristics of this niche are now made clearer by two sophisticated imaging studies. Lo Celso et al. performed live-animal tracking of individual haematopoietic cells and find that osteoblasts are enmeshed in microvessels and that different haematopoietic cell populations are localized in different areas according to their stage of differentiation. Xie et al. used newly developed ex vivo real-time imaging technology and immunoassays to trace the homing of fluorescently labelled haematopoietic stem cells in response to irradiation. They report that the membrane lining the medullary cavity of bone forms a special zone that normally maintains haematopoietic stem cells, but promotes their expansion in response to bone marrow damage. Recently haematopoietic stem cell niches have been shown to comprise osteoblastic and vascular microenvironments. This study describes a newly developed ex vivo real-time imaging technology and immunoassaying to trace the homing of highly purified GFP-expressing haematopoietic stem cells in response to irradiation. Haematopoietic stem cell (HSC) niches, although proposed decades ago1, have only recently been identified as separate osteoblastic and vascular microenvironments2,3,4,5,6. Their interrelationships and interactions with HSCs in vivo remain largely unknown. Here we report the use of a newly developed ex vivo real-time imaging technology and immunoassaying to trace the homing of purified green-fluorescent-protein-expressing (GFP+) HSCs. We found that transplanted HSCs tended to home to the endosteum (an inner bone surface) in irradiated mice, but were randomly distributed and unstable in non-irradiated mice. Moreover, GFP+ HSCs were more frequently detected in the trabecular bone area compared with compact bone area, and this was validated by live imaging bioluminescence driven by the stem-cell-leukaemia (Scl) promoter–enhancer7. HSCs home to bone marrow through the vascular system. We found that the endosteum is well vascularized and that vasculature is frequently localized near N-cadherin+ pre-osteoblastic cells, a known niche component. By monitoring individual HSC behaviour using real-time imaging, we found that a portion of the homed HSCs underwent active division in the irradiated mice, coinciding with their expansion as measured by flow assay. Thus, in contrast to central marrow, the endosteum formed a special zone, which normally maintains HSCs but promotes their expansion in response to bone marrow damage.

Genome 10K: A Proposal to Obtain Whole-Genome Sequence for 10 000 Vertebrate Species

Abstract: American Genetic Association, Gordon and Betty Moore Foundation, NHGRI Intramural Sequencing Center, and UCSC Alumni Association to cost of the Genome 10K workshop; Howard Hughes Medical Institute to D. H.; Gordon and Betty Moore Foundation to S. C. S.; A

The hierarchical structure of well-being.

Abstract: Theories of hedonic, eudaimonic, and social well-being provide 3 extensively studied models for explaining flourishing mental health. Few studies have examined whether these models can be integrated into a comprehensive structure of well-being. The present study builds upon previous theoretical and empirical work to determine the complex relationships among these 3 models of well-being. Confirmatory factor analysis techniques were used to test a series of models in order to (a) confirm the proposed latent structures of hedonic, eudaimonic, and social well-being and (b) examine whether these models could be successfully integrated into a hierarchical structure of well-being. In 2 large samples, results supported the proposed latent structures of hedonic, eudaimonic, and social well-being and indicated that the various components of well-being could be represented most parsimoniously with 3 oblique second-order constructs of hedonic, eudaimonic, and social well-being.

I-TASSER: fully automated protein structure prediction in CASP8.

Abstract: The I-TASSER algorithm for protein 3D structure prediction was tested in CASP8, with the procedure fully automated in both the Server and Human sections. The quality of the server models is close to that of human ones but incorporating more diverse templates from other servers improves the results of human predictions in the distant homology category. For the first time, the sequence-based contact predictions from machine learning techniques are found helpful for both template-based modeling (TBM) and template-free modeling (FM). In TBM, although the average accuracy of the sequence-based contact predictions is lower than that from template-based ones, the novel contacts in the sequence-based predictions, which are complementary to the threading templates in the weakly or unaligned regions, are important to improve the global and local packing of these regions. Moreover, the newly developed atomic structural refinement algorithm was tested in CASP8 and found to improve the hydrogen-bonding networks and the overall TM-score, which is mainly due to its ability of removing steric clashes so that the models can be generated from cluster centroids. Nevertheless, one of the major issues of the I-TASSER pipeline is the model selection where the best models could not be appropriately recognized when the correct templates are detected only by the minority of the threading algorithms. There are also problems related with domain-splitting and mirror image recognition which mainly influences the performance of I-TASSER modeling in the FM-based structure predictions.

Relational mechanisms, formal contracts, and local knowledge acquisition by international subsidiaries

Abstract: This research focuses on relational and contractual mechanisms and examines their impact on foreign subsidiaries' acquisition of tacit and explicit knowledge from local suppliers. Using survey data from 168 foreign subsidiaries operating in China, this study finds broad support for the proposed analytical framework. When the foreign subsidiary and supplier share common goals, the foreign subsidiary acquires greater levels of both explicit and tacit knowledge; trust between the two parties promotes the acquisition of greater levels of tacit than explicit knowledge. However, access to the local supplier network through the focal supplier enables the foreign subsidiary to acquire greater levels of explicit but not tacit knowledge. Formal contracts play a complementary role in knowledge acquisition: contracts enhance the acquisition of explicit knowledge and further strengthen the effects of relational mechanisms on tacit and explicit knowledge acquisition. Overall, these findings provide important implications for foreign subsidiaries regarding how to acquire local knowledge in host countries through both formal and informal mechanisms. Copyright © 2009 John Wiley & Sons, Ltd.

Carbon-nitrogen interactions regulate climate-carbon cycle feedbacks: results from an atmosphere-ocean general circulation model

Abstract: Inclusion of fundamental ecological interactions between carbon and nitrogen cycles in the land component of an atmosphere-ocean general circulation model (AOGCM) leads to decreased carbon uptake associated with CO2 fertil- ization, and increased carbon uptake associated with warm- ing of the climate system. The balance of these two oppos- ing effects is to reduce the fraction of anthropogenic CO2 predicted to be sequestered in land ecosystems. The primary mechanism responsible for increased land carbon storage un- der radiatively forced climate change is shown to be fertiliza- tion of plant growth by increased mineralization of nitrogen directly associated with increased decomposition of soil or- ganic matter under a warming climate, which in this partic- ular model results in a negative gain for the climate-carbon feedback. Estimates for the land and ocean sink fractions of recent anthropogenic emissions are individually within the range of observational estimates, but the combined land plus ocean sink fractions produce an airborne fraction which is too high compared to observations. This bias is likely due in part to an underestimation of the ocean sink frac- tion. Our results show a significant growth in the airborne fraction of anthropogenic CO2 emissions over the coming

Validation of the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease

Abstract: As no comprehensive assessment instrument for impulse control disorders (ICDs) in Parkinson's disease (PD) exists, the aim of this study was to design and assess the psychometric properties of a self-administered screening questionnaire for ICDs and other compulsive behaviors in PD. The Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease (QUIP) has 3 sections: Section 1 assesses four ICDs (involving gambling, sexual, buying, and eating behaviors), Section 2 other compulsive behaviors (punding, hobbyism, and walkabout), and Section 3 compulsive medication use. For validation, a convenience sample of 157 PD patients at 4 movement disorders centers first completed the QUIP, and then was administered a diagnostic interview by a trained rater blinded to the QUIP results. A shortened instrument (QUIP-S) was then explored. The discriminant validity of the QUIP was high for each disorder or behavior (receiver operating characteristic area under the curve [ROC AUC]: gambling = 0.95, sexual behavior = 0.97, buying = 0.87, eating = 0.88, punding = 0.78, hobbyism = 0.93, walkabout = 0.79). On post hoc analysis, the QUIP-S ICD section had similar properties (ROC AUC: gambling = 0.95, sexual behavior = 0.96, buying = 0.87, eating = 0.88). When disorders/behaviors were combined, the sensitivity of the QUIP and QUIP-S to detect an individual with any disorder was 96 and 94%, respectively. Scores on the QUIP appear to be valid as a self-assessment screening instrument for a range of ICDs and other compulsive behaviors that occur in PD, and a shortened version may perform as well as the full version. A positive screen should be followed by a comprehensive, clinical interview to determine the range and severity of symptoms, as well as need for clinical management.

Active structures of the Himalayan-Tibetan orogen and their relationships to earthquake distribution, contemporary strain field, and Cenozoic volcanism

Abstract: We have compiled the distribution of active faults and folds in the Himalayan-Tibetan orogen and its immediate surrounding regions into a web-based digital map. The main product of this study is a compilation of active structures that came from those documented in the literature and from our own interpretations based on satellite images and digital topographic data. Our digital tectonic map allows a comparison between the distribution and kinematics of active faults with the distribution and focal mechanisms of earthquakes. The active tectonic map is also compared with the contemporary velocity field, obtained by global positioning system studies, that allows a better assessment of partitioning of decadal strain-rate fields across individual active structures that may have taken tens of thousands of years to a million years to develop. The active tectonic map provides a basis to evaluate whether the syncollisional late Cenozoic volcanism in Tibet was spatially related to the distribution and development of the active faults in the same area. These comparisons lead to the following findings: (1) Tibetan earthquakes >M5 correlate well with mappable surface faults; (2) the short-term strain-rate field correlates well with the known kinematics of the active faults and their geologic slip rates; and (3) Tibetan Neogene–Quaternary volcanism is controlled by major strike-slip faults along the plateau margins but has no clear relationship with active faults in the plateau interior. Although not explored in this study, our digital tectonic map and the distribution of Cenozoic volcanism in Tibet can also be used to correlate surface geology with geophysical properties such as seismic velocity variations and shear wave-splitting data across the Himalaya and Tibet.

Practice parameter update: management issues for women with epilepsy - focus on pregnancy (an evidence-based review): teratogenesis and perinatal outcomes. Report of the Quality Standards Subcommittee and Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology and American Epilepsy Society

Abstract: Objective: To reassess the evidence for management issues related to the care of women with epilepsy (WWE) during pregnancy. Methods: Systematic review of relevant articles published between January 1985 and June 2007. Results: It is highly probable that intrauterine first-trimester valproate (VPA) exposure has higher risk of major congenital malformations (MCMs) compared to carbamazepine and possible compared to phenytoin or lamotrigine. Compared to untreated WWE, it is probable that VPA as part of polytherapy and possible that VPA as monotherapy contribute to the development of MCMs. It is probable that antiepileptic drug (AED) polytherapy as compared to monotherapy regimens contributes to the development of MCMs and to reduced cognitive outcomes. For monotherapy, intrauterine exposure to VPA probably reduces cognitive outcomes. Further, monotherapy exposure to phenytoin or phenobarbital possibly reduces cognitive outcomes. Neonates of WWE taking AEDs probably have an increased risk of being small for gestational age and possibly have an increased risk of a 1-minute Apgar score of <7. Recommendations: If possible, avoidance of valproate (VPA) and antiepileptic drug (AED) polytherapy during the first trimester of pregnancy should be considered to decrease the risk of major congenital malformations (Level B). If possible, avoidance of VPA and AED polytherapy throughout pregnancy should be considered to prevent reduced cognitive outcomes (Level B). If possible, avoidance of phenytoin and phenobarbital during pregnancy may be considered to prevent reduced cognitive outcomes (Level C). Pregnancy risk stratification should reflect that the offspring of women with epilepsy taking AEDs are probably at increased risk for being small for gestational age (Level B) and possibly at increased risk of 1-minute Apgar scores of <7 (Level C).

Assessment: Botulinum neurotoxin in the treatment of autonomic disorders and pain (an evidence-based review): Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology

Abstract: Objective: To perform an evidence-based review of the safety and efficacy of botulinum neurotoxin (BoNT) in the treatment of autonomic and urologic disorders and low back and head pain. Methods: A literature search was performed including MEDLINE and Current Contents for therapeutic articles relevant to BoNT and the selected indications. Authors reviewed, abstracted, and classified articles based on the quality of the study (Class I–IV). Conclusions and recommendations were developed based on the highest level of evidence and put into current clinical context. Results: The highest quality literature available for the respective indications was as follows: axillary hyperhidrosis (two Class I studies); palmar hyperhidrosis (two Class II studies); drooling (four Class II studies); gustatory sweating (five Class III studies); neurogenic detrusor overactivity (two Class I studies); sphincter detrusor dyssynergia in spinal cord injury (two Class II studies); chronic low back pain (one Class II study); episodic migraine (two Class I and two Class II studies); chronic daily headache (four Class II studies); and chronic tension-type headache (two Class I studies). Recommendations: Botulinum neurotoxin (BoNT) should be offered as a treatment option for the treatment of axillary hyperhidrosis and detrusor overactivity (Level A), should be considered for palmar hyperhidrosis, drooling, and detrusor sphincter dyssynergia after spinal cord injury (Level B), and may be considered for gustatory sweating and low back pain (Level C). BoNT is probably ineffective in episodic migraine and chronic tension-type headache (Level B). There is presently no consistent or strong evidence to permit drawing conclusions on the efficacy of BoNT in chronic daily headache (mainly transformed migraine) (Level U). While clinicians’ practice may suggest stronger recommendations in some of these indications, evidence-based conclusions are limited by the availability of data. Neurology ® 2008;70:1707–1714

Mergers and Acquisitions of Financial Institutions: A Review of the Post-2000 Literature

Abstract: This paper provides a review of the recent financial institution mergers and acquisition (M&A) literature covering over 150 studies. Several robust themes emerge in the post-2000 literature. North American bank mergers are (or can be) efficiency improving, although the event-study literature presents a mixed picture regarding stockholder wealth creation. In contrast, European bank mergers appear to have resulted in both efficiency gains and stockholder value enhancement. There is robust evidence linking high CEO compensation to merger activity and strong implications that deals can be motivated by the desire to obtain ‘too-big-to-fail’ status and reap the associated subsidies. Evidence on the impact of both geographic and product diversification via merger is mixed. There is growing evidence that financial institution M&As can adversely impact certain types of borrowers, depositors, and other external stakeholders.

Proposing the Online Community Self-Disclosure Model: The Case of Working Professionals in France and the UK Who Use Online Communities

Abstract: The global use of online communities has exploded to involve hundreds of millions of users. Despite the tremendous social impact and business opportunities afforded by these communities, little information systems (IS) research has addressed them - especially in a cross-cultural context. Our research proposes an online community self-disclosure model, tested in a cross-cultural setting using data provided by French and British working professionals. Our model is based on social exchange theory (SET) and social penetration theory (SPT), as well as on cross-cultural theory related to individualism-collectivism. SET explains that individuals engage in relationships when the perceived costs associated with the relationship are less than the expected benefits. SPT extends SET to explain that individuals participate in self-disclosure to foster relationships - reciprocation is the primary benefit of self-disclosure, whereas risk is the foundational cost of self-disclosure. Our study established several important findings: Positive social influence to use an online community increases online community self-disclosure; reciprocity increases self-disclosure; online community trust increases self-disclosure; and privacy risk beliefs decrease self-disclosure. Meanwhile, a tendency toward collectivism increases self-disclosure. We further found that French participants had higher scores on horizontal individualism than British participants. Several other findings and their implications for practice are also discussed.