202,195 research outputs found
Letter from Gary M. Roach
No full textA letter from Gary M. Roach discussing various family members.https://mavmatrix.uta.edu/specialcollections_silasestesfamilypapers/1176/thumbnail.jp
lettie-roach/analysis_antarctic-asym: Code for journal article
No full textAnalysis code, processed observational data and climate model output required to produce figures for the journal article
Roach, L. A., Eisenman, I., Wagner, T. J., Blanchard-Wrigglesworth, E., and Bitz, C. M.. Asymmetry in the seasonal cycle of Antarctic sea ice due to insolation (2022). Nature Geoscience. https://doi.org/10.1038/s41561-022-00913-
Will probate records from Gary M. Roach
No full textA letter from Gary M. Roach and will probate records for James Estes.https://mavmatrix.uta.edu/specialcollections_silasestesfamilypapers/1177/thumbnail.jp
Endocrine disruption in juvenile roach from English rivers: A preliminary study
No full textJuvenile roach Rutilus rutilus from seven rivers of varying water quality were examined for evidence of endocrine disruption. The majority of roach from five of these rivers had femalelike reproductive ducts. The results suggest that juvenile, rather than adult, fish could be used in studies of endocrine disruption in wild fish populations
Assessing the Sensitivity of Different Life Stages for Sexual Disruption in Roach (Rutilus rutilus) Exposed to Effluents from Wastewater Treatment Works
No full textSurveys of U.K. rivers have shown a high incidence of sexual disruption in populations of wild roach (Rutilus rutilus) living downstream from wastewater treatment works (WwTW), and the degree of intersex (gonads containing both male and female structural characteristics) has been correlated with the concentration of effluent in those rivers. In this study, we investigated feminized responses to two estrogenic WwTWs in roach exposed for periods during life stages of germ cell division (early life and the postspawning period). Roach were exposed as embryos from fertilization up to 300 days posthatch (dph; to include the period of gonadal sex differentiation) or as postspawning adult males, and including fish that had received previous estrogen exposure, for either 60 or 120 days when the annual event of germ cell proliferation occurs. Both effluents induced vitellogenin synthesis in both life stages studied, and the magnitude of the vitellogenic responses paralleled the effluent content of steroid estrogens. Feminization of the reproductive ducts occurred in male fish in a concentration-dependent manner when the exposure occurred during early life, but we found no effects on the reproductive ducts in adult males. Depuration studies (maintenance of fish in clean water after exposure to WwTW effluent) confirmed that the feminization of the reproductive duct was permanent. We found no evidence of ovotestis development in fish that had no previous estrogen exposure for any of the treatments. In wild adult roach that had previously received exposure to estrogen and were intersex, the degree of intersex increased during the study period, but this was not related to the immediate effluent exposure, suggesting a previously determined programming of ovotestis formation
Richard Roach
No full textDr. Richard Roach has served for almost 10 years as Embry-Riddle’s liaison to the Southern Association of Colleges and Schools, Commission on Colleges (SACSCOC or “SACS”). He keeps the university informed on changes in accreditation requirements, reports the university’s many substantive changes to SACSCOC, oversees processes related to assessments and strategic planning, and supports academic departments in their various program accreditations.
Since joining ERAU he has overseen the development of current on-line course evaluations, academic program review, academic assessments, and strategic planning and assessment processes. He guided the three campuses in the successful reaffirmation of regional accreditation in 2012 and administered the initial development of the Ignite undergraduate research initiatives on the three campuses as an integral part of that reaffirmation.
He was born in New Mexico, grew up in Texas, received his undergraduate degree (English and Speech education) from the University of Houston, and obtained his master’s degree and doctorate from Southwestern Baptist Theological Seminary in Fort Worth. He was self-employed in construction for 5 years and pastored 18 years before going into higher education accreditation at Texas A&M University-Texarkana for 7 years. He came to Embry-Riddle in July 2005.
When asked what he would be doing in four months if he won the lottery, he replied, “I’d be right here doing what I am doing now, supporting this university because, for me, this is the greatest job on earth.”
Dr. Roach is married to Peggy (Enrollment Management, Worldwide campus), has three grown sons (David, Tyler and Wesley), and lives in DeBary. His hobbies include meditation and devotions, flower gardening, outdoor activities and antiquing.https://commons.erau.edu/lep-images/1027/thumbnail.jp
Predicting the ecological consequences of river management for a riverine cyprinid fish.
No full textCurrent river management seeks to resolve a compromise between stakeholder interests, ecosystem services provision and conservation aims, especially in relation to assessment of ecosystem health. While management decisions should be evidenced-based, current population and habitat models fail to incorporate fish behaviour and the interactions between fish and their environment, thus limiting their ability to predict management-relevant, population responses to environmental change. In order to address these weaknesses, an individual-based model is developed and parameterised to predict the distribution and growth of roach (Rutilus rutilus), a common, generalist, freshwater fish; known to be typically dominant in heavily modified rivers. Such a model seeks to build on current management models and practices, with emphasis on improving recruitment of juvenile roach. Virtual forager parameters are derived from foraging experiments, published investigations, models of roach behaviour and bioenergetics. Data collected from field studies in a typical, highly modified, lowland river are used to describe the environment and initial fish population with subsequent data on fish population trends used to validate the IBM, under a pattern-oriented modelling approach; specifically growth rate and habitat distribution patterns. River management practices including the removal of in-stream aquatic macrophytes and regulation of flow regime for flood risk management are predicted as potentially damaging to roach recruitment, subsequent year-class strength and therefore, populations in subsequent years. Recommendations for more sympathetic management schemes are provided. The modelling framework described here can be used to produce robust predictions of roach population patterns in riverine habitats and allows the user to test the impact of environmental change on cyprinid fish, enabling the modelling system to be used to develop proactive, evidence-based management in light of current rates of environmental change
Habitat selection and indirect interactions in fish ommunities
No full textTo increase the understanding of freshwater lake ecosystems, I have studied the habitat selection of perch (Perca fluviatilis L.), roach (Rutilus rutilus (L.)), and vendace (Coregonus albula (L.)). These fish species use the pelagic and the littoral-benthic habitats in lakes to different extents. Perch and roach are omnivorous, and perch become piscivorous at larger sizes. Vendace is a pelagic species specialized in eating zooplankton. Vendace was expected to affect biotic interactions and habitat use of roach and perch, both directly and indirectly.
I used monitoring data to examine how species distribution patterns, as well as population structures, depended on species composition. In a predation experiment, I studied the relative predation sensitivity as well as evasive behaviours of roach and vendace, with piscivorous perch used as predators. In foraging experiments in aquaria, I studied foraging efficiencies and swimming performances of roach and vendace eating zooplankton in different temperature and light treatments. I then applied metabolic models for roach and vendace, respectively, to compare their net energy gain in different abiotic conditions.
Roach used the pelagic habitat less, and the biomass of roach was lower in lakes with vendace. Results did not support the prediction that perch populations would benefit from the presence of vendace. However, results indicated that a release of competition for small perch may be mediated by vendace, through changed habitat use of roach, increasing the possibilities for predation. Roach and vendace were similar in their sensitivity to predation, indicating that energy gain can explain their habitat use. Foraging efficiencies did not explain the habitat use of roach and vendace in the field. However, the net energy gain in different abiotic conditions, could explain observed patterns of their habitat use in lakes.
This thesis shows how the trade-off between mortality and net energy gain is manifested in habitat use. Including habitat selection in ecological studies may increase our understanding of biotic interactions. Metabolic costs as well as foraging abilities in different abiotic conditions are important for explaining the habitat use of species. Such knowledge can make it possible to forecast how interacting fish species may be affected by environmental change
Receipt, Erasters N. Roach to Frank M. R. Roach, October 16, 1896
No full textThis handwritten receipt, dated October 16, 1896, is for payment of fifty dollars on a note. The payment was made by Frank M. R. Roach to Erasters N. Roach. The receipt is written on lined paper that has light tearing on the edge.https://scholarsjunction.msstate.edu/fvw-manuscripts-original-manuscripts/1082/thumbnail.jp
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