Ichthyoplankton community structure and comparative trophodynamics in an estuarine transition zone

Surveys were conducted to evaluate and compare assemblage structure and trophodynamics of ichthyoplankton, and their variability, in an estuarine transition zone. Environmental gradients in the saltfront region of the Patuxent River subestuary, Chesapeake Bay, were hypothesized to define spatiotemporal distributions and assemblages of ichthyoplankton. Larval fishes, zooplankton, and hydrographic data were collected during spring through early summer 2000 and 2001. Larvae of 28 fish species were collected and species richness was similar each year. Total larval abundance was highest in the oligohaline region down-estuary of the salt front in 2000, but highest at the salt front in 2001. Larvae of anadromous fishes were most abundant at or up-estuary of the salt front in both years. Two ichthyoplankton assemblages were distinguished: 1) riverine—characterized predominantly by anadromous species (Moronidae and Alosinae); and 2) estuarine—characterized predominantly by naked goby (Gobiosoma bosc) (Gobiidae). Temperature, dissolved oxygen, salinity-associated variables (e.g., salt-front location), and concentrations of larval prey, specifically the calanoid copepod Eurytemora affinis and the cladoceran Bosmina longirostris, were important indicators of larval fish abundance. In the tidal freshwater region up-estuary of the salt front, there was substantial diet overlap between congeneric striped bass (Morone saxatilis) and white perch (M. americana) larvae, and also larvae of alewife (Alosa pseudoharengus) (overlap= 0.71–0.93). Larval abundance, taxonomic diversity, and dietary overlap were highest within and up-estuary of the salt front, which serves to both structure the ichthyoplankton community and control trophic relationships in the estuarine transition zone

Portfolio Optimization: A Modeling Perspective

Investing is critical in the business world and is an avenue to make profit for many. Making the decisions of what to invest in involves intricate mathematics in order to reduce risk. We investigate portfolio optimization, which is a branch of economic and financial modeling that typically has the goal of maximizing an investment\u27s expected return. We explore a linear programming approach to a decision model for a first time investor. Our results are compared to our expectation and different outcomes are computed based on adjusting our models used for calculating rates of return and failure rates in order to best capture reality. We then explore how changing our constraint of confidence in our investment affects the distribution of the model

MS

thesisLittle is written in regard to the stresses encountered in pediatric Nursing;. The insufficiency of evidence confirming the belief that critical care Nursing; is more stressful than other types of Nursing; care, together with the limited knowledge of pediatric Nursing; stress, provided the impetus for this study. The purpose of the research was to investigate and compare the situational stressors perceived and identified by pediatric intensive and non-intensive care nurses in terms of degree, frequency of occurrence, and source of stress. Questionnaire surveys listing 51 items requiring a numerical response according to graphic scale were distributed of full-time staff nurses in two intensive care and two non-intensive care units in a pediatric hospital. Respondents were instructed to evaluate each item according to its frequency of occurrence and degree of severity in the Nursing; unit. Acceptable questionnaires were received for 27 ICU nurses and 19 non-ICU nurses. Evidence was found supporting the belief that ICU and non-ICU Nursing; stressors were not comparable; however, the non-ICU nurses reported more stresses, in general, both in frequency and degree. Several expected common stressors were identified, yet some differences particular to one group or the other were also recognized. Statistically significant differences were reported in higher frequencies and degrees of stress in the non-intensive care group. Eleven specific stressors were identified, most of which were in the general categories of physical work environment and interpersonal relationships. Five statistically significant stressors were reported in higher frequencies in the ICU group; there were in the category of patient care and the remainder fell within other categories. Most of the coping strategies reportedly practiced were mutually employed by both ICU and non-ICU nurse

Cyber Bullying and Victimization: Psychosocial Characteristics of Bullies, Victims, and Bully/Victims

This study explored cyber bullying and victimization. The use of technology as a vehicle for peer victimization is increasing and is associated with a risk of psychosocial maladjustment (Finkelhor, et al., 2000; Wolak, et al., 2006; Ybarra & Mitchell, 2004a, 2004b). It is thought to peak during middle school (Harris & Petrie, 2002); thus, the sample included 6th, 7th, and 8th graders who identified themselves as cyber bullies, victims, or bully/victims. Hypotheses were as follows: face-to-face bullies and victims would also be involved in cyber bullying and victimization, with females being more involved than males; cyber bullying and victimization would be associated with psychosocial maladjustment; externalizing behaviors would be more common among cyber bullies while internalizing symptoms, loneliness and low self-esteem would be more common among cyber victims; cyber bully/victims and individuals who were victims of both face-to-face bullying and cyber bullying would exhibit the poorest overall psychosocial adjustment. The study also sought to identify predictor variables related to cyber victimization, with loneliness and low self-esteem hypothesized as the most predictive. Analyses included chi-square tests of independence, a series of one-way ANOVAS and discriminant function analysis. Assessments included the Youth Self (Achenbach, 1991) (for internalizing, externalizing and total problems), the Children\u27s Loneliness Scale (Asher & Wheeler, 1985) for loneliness, and the Self-Esteem Questionnaire-Short Form (DuBois, et al., 1996) for peer and global self-esteem. Results indicated that 69% of participants were involved in cyber bullying and/or victimization. A significant overlap was found among face-to-face bullies and victims and cyber bullies and victims. Females were over-represented among cyber bullies, victims, and bully/victims. The psychosocial characteristics of cyber victims, and bully/victims included externalizing behaviors, total problems, and low peer self-esteem. Cyber bullies did not endorse any psychosocial symptoms of maladjustment. Cyber bully/victims and victims of both face-to-face and cyber bullying exhibited the poorest psychosocial adjustment. Externalizing behaviors and total problems were most predictive of cyber victim status. Increased awareness about the use of technology as a vehicle for bullying and identification of potential problems associated with cyber bullying and victimization will aid parents, educators, and psychologists in developing intervention and prevention strategies

Constitutional Law - Search Warrants - Health and Safety Inspections

Health and Safety Inspections- The Fourth Amendment guarantees that a person may not be convicted for refusing to consent to a health or safety inspection of his residence or place of business to be made without a search warrant. Camara v. Municipal Court, 87 S. Ct. 1727 (1967). See v. City of Seattle, 87 S. Ct. 1737 (1967)

Prepayment Health Care Plan Enabling Acts - Are Their Restrictive Features Constitutional?

Illness is something which afflicts the rich as well as the poor, the affluent as well as the downtrodden. It does not choose its host according to social position, educational background, or economic status. In this century the medical sciences and the medical professions have minimized the hazards of illness. Yet the costs of preventing or curing illness, and the financial burden placed upon the victim, persists and grows

Design and Simulation of Self-Organizing Microbial Cellular Automata

This paper discusses the design and implementation of cellular automata based on the alteration of genetic sequences in bacteria. The work is composed of five chapters covering the problem, the system’s design, the software simulation of the system and future issues on the problem. The section covering the problem explores the reasons for this work as well as issues that this work solves. The section covering system design details the modified genetic sequences and the algorithm that these sequences implement. The simulation section describes the layout of an experiment along with the test cases experimented on. Finally, the future work section points out lacking information from the work or possible difficulties this solution reveals