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.

Piscivores, trophic cascades, and lake management.

Abstract: The concept of cascading trophic interactions predicts that an increase in piscivore biomass in lakes will result in decreased planktivorous fish biomass, increased herbivorous zooplankton biomass, and decreased phytoplankton biomass. Though often accepted as a paradigm in the ecological literature and adopted by lake managers as a basis for lake management strategies, the trophic cascading interactions hypothesis has not received the unequivocal support (in the form of rigorous experimental testing) that might be expected of a paradigm. Here we review field experiments and surveys, testing the hypothesis that effects of increasing piscivore biomass will cascade down through the food web yielding a decline in phytoplankton biomass. We found 39 studies in the scientific literature examining piscivore effects on phytoplankton biomass. Of the studies, 22 were confounded by supplemental manipulations (e.g., simultaneous reduction of nutrients or removal of planktivores) and could not be used to assess piscivore effects. Of the 17 nonconfounded studies, most did not find piscivore effects on phytoplankton biomass and therefore did not support the trophic cascading interactions hypothesis. However, the trophic cascading interactions hypothesis also predicts that lake systems containing piscivores will have lower phytoplankton biomass for any given phosphorus concentration. Based on regression analyses of chlorophyll–total phosphorus relationships in the 17 nonconfounded piscivore studies, this aspect of the trophic cascading interactions hypothesis was supported. The slope of the chlorophyll vs. total phosphorus regression was lower in lakes with planktivores and piscivores compared with lakes containing only planktivores but no piscivores. We hypothesize that this slope can be used as an indicator of “functional piscivory” and that communities with extremes of functional piscivory (zero and very high) represent classical 3- and 4-trophic level food webs.

Sulfur stable isotope indicators of residency in estuarine fish

Abstract: Estuarine fish may remain as residents in areas with favorable conditions for feeding and refuge, but become mobile and transient where conditions are less favorable. We developed a new approach involving sulfur stable isotope (d34S) distributions in fish muscle tissue to track residents and transients across estuarine salinity zones. Salinity tracking was based on d34S contrasts between freshwater and marine waters. This 5-yr study of two Louisiana estuaries showed that riverine and upper-estuarine fish consistently had low d34S values (25% to +5%) in contrast to fish from the lower, more marine portion of estuaries that had higher d34S values (11–17%). Residents were identified using tests of normality within community-level d34S distributions, and conceptually were considered animals permanently residing at the sampling station but also any animals present from nearby areas with similar salinities. Transients had d34S values atypical of both the location of capture and the local salinity regime. Results showed good resolution of fish movement at small 0.1–4-km scales for low-salinity (, 2) upper-estuary stations, and good detection of long-range migrants from the upper estuary into the lower estuary at a coarser spatial scale of 10–30 km. On an average basis, O of the estuarine fish fauna was resident and M transient. Transients were a minority in most species but commonly included small as well as large fish. This novel d34S approach may be a general technique for evaluating fish residency and movement across salinity zones in

Effect of visual art on patient anxiety and agitation in a mental health facility and implications for the business case

Abstract: There is a growing body of evidence on the impact of the environment on health and well-being. This study focuses on the impact of visual artworks on the well-being of psychiatric patients in a multi-purpose lounge of an acute care psychiatric unit. Well-being was measured by the rate of pro re nata (PRN) medication issued by nurses in response to visible signs of patient anxiety and agitation. Nurses were interviewed to get qualitative feedback on the patient response. Findings revealed that the ratio of PRN/patient census was significantly lower on the days when a realistic nature photograph was displayed, compared to the control condition (no art) and abstract art. Nurses reported that some patients displayed agitated behaviour in response to the abstract image. This study makes a case for the impact of visual art on mental well-being. The research findings were also translated into the time and money invested on PRN incidents, and annual cost savings of almost $US30,000 a year was projected. This research makes a case that simple environmental interventions like visual art can save the hospital costs of medication, and staff and pharmacy time, by providing a visual distraction that can alleviate anxiety and agitation in patients.