2,124 research outputs found
A Limnological Study of Ricks Pond and the Gulpha Creek Drainage in Garland County, Arkansas
A limnological investigation of Ricks Pond and the Gulpha Creek drainage of Garland County, Arkansas was conducted between 1 June 1978, and 21 August 1978. Water samples taken from ten stations on three different dates indicated that the stream and pond systems were typical in water quality characteristics of other small, high gradient streams and impoundments in the Ouachita Mountains of Arkansas. In Ricks Pond, thermal stratification occurred along with the development of an oxygen deficient zone below a depth of one meter. Other water quality parameters indicated that Ricks Pond is a moderately productive ecosystem, with the productivity limited by the nitrogen species. The fecal coliform bacterial counts were very low, indicating no direct input of excessive amounts of fecal matter into the system during the present study. However, a Hot Springs city sewer line runs through the pond, and two manholes emerge from the pond\u27s surface. The possibility exists that this sewer line could discharge raw sewage into Ricks Pond during periods of high water. A biological investigation was also conducted in the study area, and lists of the phytoplankton, periphyton, higher aquatic vegetation, zooplankton, benthic macroinvertebrates, and fishes are presented. Twenty-seven species of fishes were collected from the Gulpha Creek drainage, and no rare or endangered forms were found. Ricks Pond is best-suited for the establishment of a put- and-take fishery for channel catfish, Ictalurus punctatus. The following recommendations were made for the establishment of such a fishery: (1) Renovation of the pond by draining and deepening it; (2) Removal of the sewer line from the pond; (3) Stocking of catchable size channel catfish at the rate of approximately 300-400 pounds per acre; (4) Periodic monitoring of the water quality
Ca2+ store depletion causes STIM1 to accumulate in ER regions closely associated with the plasma membrane
Stromal interacting molecule 1 (STIM1), reported to be an endoplasmic reticulum (ER) Ca2+ sensor controlling store-operated Ca2+ entry, redistributes from a diffuse ER localization into puncta at the cell periphery after store depletion. STIM1 redistribution is proposed to be necessary for Ca2+ release–activated Ca2+ (CRAC) channel activation, but it is unclear whether redistribution is rapid enough to play a causal role. Furthermore, the location of STIM1 puncta is uncertain, with recent reports supporting retention in the ER as well as insertion into the plasma membrane (PM). Using total internal reflection fluorescence (TIRF) microscopy and patch-clamp recording from single Jurkat cells, we show that STIM1 puncta form several seconds before CRAC channels open, supporting a causal role in channel activation. Fluorescence quenching and electron microscopy analysis reveal that puncta correspond to STIM1 accumulation in discrete subregions of junctional ER located 10–25 nm from the PM, without detectable insertion of STIM1 into the PM. Roughly one third of these ER–PM contacts form in response to store depletion. These studies identify an ER structure underlying store-operated Ca2+ entry, whose extreme proximity to the PM may enable STIM1 to interact with CRAC channels or associated proteins
Environmental Evaluation Report onn Various Completed Channel Improvement Projects in Eastern Arkansas
The objective of this report is to evaluate the beneficial and adverse effects that certain channel improvement projects have had on the natural or man-made environments of selected areas in eastern Arkansas. This evaluation will be used as a baseline for determining the immediate and long-term effects that a project may have on the existing environment of the Village Creek Basin
A Better Index of Body Adiposity
Obesity is a growing problem in the United States and throughout the world. It is a risk factor for many chronic diseases. The BMI has been used to assess body fat for almost 200 years. BMI is known to be of limited accuracy, and is different for males and females with similar %body adiposity. Here, we define an alternative parameter, the body adiposity index (BAI = ((hip circumference)/((height)1.5)–18)). The BAI can be used to reflect %body fat for adult men and women of differing ethnicities without numerical correction. We used a population study, the “BetaGene” study, to develop the new index of body adiposity. %Body fat, as measured by the dual-energy X-ray absorptiometry (DXA), was used as a “gold standard” for validation. Hip circumference (R = 0.602) and height (R = −0.524) are strongly correlated with %body fat and therefore chosen as principal anthropometric measures on which we base BAI. The BAI measure was validated in the “Triglyceride and Cardiovascular Risk in African-Americans (TARA)” study of African Americans. Correlation between DXA-derived %adiposity and the BAI was R = 0.85 for TARA with a concordance of C_b = 0.95. BAI can be measured without weighing, which may render it useful in settings where measuring accurate body weight is problematic. In summary, we have defined a new parameter, the BAI, which can be calculated from hip circumference and height only. It can be used in the clinical setting even in remote locations with very limited access to reliable scales. The BAI estimates %adiposity directly
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The characteristics of cognitive neuroscience tests in a schizophrenia cognition clinical trial: Psychometric properties and correlations with standard measures.
In comparison to batteries of standard neuropsychological tests, cognitive neuroscience tests may offer a more specific assessment of discrete neurobiological processes that may be aberrant in schizophrenia. However, more information regarding psychometric properties and correlations with standard neuropsychological tests and functional measures is warranted to establish their validity as treatment outcome measures. The N-back and AX-Continuous Performance Task (AX-CPT) are two promising cognitive neuroscience tests designed to measure specific components of working memory and contextual processing respectively. In the current study, we report the psychometric properties of multiple outcome measures from these two tests as well as their correlations with standard neuropsychological measures and functional capacity measures. The results suggest that while the AX-CPT and N-back display favorable psychometric properties, they do not exhibit greater sensitivity or specificity with functional measures than standard neurocognitive tests
Spatially targeted nature-based solutions can mitigate climate change and nature loss but require a systems approach
Funding Information: This study was funded by the Royal Society for the Protection of Birds (RSPB) and Natural England (project code ECM 58632). The Breeding Bird Survey is a Partnership between the BTO, RSPB, and Joint Nature Conservation Committee (on behalf of Natural Resources Wales, Natural England, Council for Nature Conservation and Countryside, and NatureScot) and relies on volunteer surveyors. Simon Gillings provided tetrad-level predictions of relative abundance for wading birds. We are grateful to members of the RSPB steering group, who contributed to the development of our scenarios, and Profs. Tim Benton and Andrew Balmford who commented on an earlier version of this manuscript. Conceptualization, T.F. R.B.B. T.B.-L. G.M.B. W.J.P. and R.H.F.; methodology, T.F. T.B.-L. J.P.C. D.M. P.S. and R.H.F.; software, T.F.; formal analysis, T.F.; resources, D.M.; data curation, T.F.; writing – original draft, T.F.; writing – review & editing, R.B.B. T.B.-L. G.M.B. J.P.C. D.M. P.S. W.J.P. and R.H.F.; visualization, T.F.; supervision, W.J.P. The authors declare no competing interests. Publisher Copyright: © 2023 The AuthorsPeer reviewedPublisher PD
Science and Ideology in Economic, Political, and Social Thought
This paper has two sources: One is my own research in three broad areas: business cycles, economic measurement and social choice. In all of these fields I attempted to apply the basic precepts of the scientific method as it is understood in the natural sciences. I found that my effort at using natural science methods in economics was met with little understanding and often considerable hostility. I found economics to be driven less by common sense and empirical evidence, then by various ideologies that exhibited either a political or a methodological bias, or both. This brings me to the second source: Several books have appeared recently that describe in historical terms the ideological forces that have shaped either the direct areas in which I worked, or a broader background. These books taught me that the ideological forces in the social sciences are even stronger than I imagined on the basis of my own experiences.
The scientific method is the antipode to ideology. I feel that the scientific work that I have done on specific, long standing and fundamental problems in economics and political science have given me additional insights into the destructive role of ideology beyond the history of thought orientation of the works I will be discussing
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Aging is associated with positive responding to neutral information but reduced recovery from negative information
Studies on aging and emotion suggest an increase in reported positive affect, a processing bias of positive over negative information, as well as increasingly adaptive regulation in response to negative events with advancing age. These findings imply that older individuals evaluate information differently, resulting in lowered reactivity to, and/or faster recovery from, negative information, while maintaining more positive responding to positive information. We examined this hypothesis in an ongoing study on Midlife in the US (MIDUS II) where emotional reactivity and recovery were assessed in a large number of respondents (N = 159) from a wide age range (36–84 years). We recorded eye-blink startle magnitudes and corrugator activity during and after the presentation of positive, neutral and negative pictures. The most robust age effect was found in response to neutral stimuli, where increasing age is associated with a decreased corrugator and eyeblink startle response to neutral stimuli. These data suggest that an age-related positivity effect does not essentially alter the response to emotion-laden information, but is reflected in a more positive interpretation of affectively ambiguous information. Furthermore, older women showed reduced corrugator recovery from negative pictures relative to the younger women and men, suggesting that an age-related prioritization of well-being is not necessarily reflected in adaptive regulation of negative affect
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Filter system cost comparison for IGCC and PFBC power systems
A cost comparison was conducted between the filter systems for two advanced coal-based power plants. The results from this study are presented. The filter system is based on a Westinghouse advanced particulate filter concept, which is designed to operate with ceramic candle filters. The Foster Wheeler second-generation 453 MWe (net) pressurized fluidized-bed combustor (PFBC) and the KRW 458 MWe (net) integrated gasification combined cycle (IGCC) power plants are used for the comparison. The comparison presents the general differences of the two power plants and the process-related filtration conditions for PFBC and IGCC systems. The results present the conceptual designs for the PFBC and IGCC filter systems as well as a cost summary comparison. The cost summary comparison includes the total plant cost, the fixed operating and maintenance cost, the variable operating and maintenance cost, and the effect on the cost of electricity (COE) for the two filter systems
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