Homing orientation in salamanders: A mechanism involving chemical cues

A detailed description is given of experiments made to determine the senses and chemical cues used by salamanders for homing orientation. Sensory impairment and cue manipulative techniques were used in the investigation. All experiments were carried out at night. Results show that sense impaired animals did not home as readily as those who were blind but retained their sensory mechanism. This fact suggests that the olfactory mechanism is necessary for homing in the salamander. It was determined that after the impaired salamander regenerated its sensory mechanism it too returned home. It was concluded that homing ability in salamanders is direction independent, distant dependent, and vision independent

Nitric oxide and synaptic function

The free radical gas nitric oxide (NO) is a recently identified neuronal messenger that carries out diverse signaling tasks in both the central and peripheral nervous systems. Whereas most neurotransmitters are packaged in synaptic vesicles and secreted in a Ca2+-dependent manner from specialized nerve endings, NO is an unconventional transmitter which is not packaged in vesicles, but rather diffuses from its site of production in the absence of any specialized release machinery. The lack of a requirement for release apparatus raises the possibility that NO can be released from both pre- and postsynaptic neuronal elements. In addition, because NO is gaseous and extremely membrane permeant, it can bypass normal signal transduction routes involving interactions with synaptic membrane receptors. Although the targets of NO have not yet been completely described, it is known that NO can bind to the iron contained in heine groups, leading to conformational changes in associated proteins, such as guanylyl cyclase

An empirical analysis of the distribution of overshoots in a stationary Gaussian stochastic process

The frequency distribution of overshoots in a stationary Gaussian stochastic process is analyzed. The primary processes involved in this analysis are computer simulation and statistical estimation. Computer simulation is used to simulate stationary Gaussian stochastic processes that have selected autocorrelation functions. An analysis of the simulation results reveals a frequency distribution for overshoots with a functional dependence on the mean and variance of the process. Statistical estimation is then used to estimate the mean and variance of a process. It is shown that for an autocorrelation function, the mean and the variance for the number of overshoots, a frequency distribution for overshoots can be estimated

STRUCTURAL CHANGE IN U.S. CHICKEN AND TURKEY SLAUGHTER

Cost function analyses using data from the U.S. Bureau of the Census reveal substantial scale economies in chicken and turkey slaughter. These economies show no evidence of diminishing as plant size increases, are much greater than those realized in cattle and hog slaughter, and have resulted in a huge increase in plant size over the 1972-92 period. The findings also suggest that consolidation in the chicken and turkey slaughter industry is likely to continue, particularly if the growth in the demand for poultry diminishes.chicken slaughter, turkey slaughter, production costs, structural change, Livestock Production/Industries,

Ironing Out Anemia: Assessing the Role of Marketplace Factors and Government Investment Incentives in Shaping East African Pharmaceutical Markets

Africa suffers from the highest disease burden in the world, with over half of the population lacking regular access to essential medicines (Owoeye, 2014, p.214; Chaudhuri & West, 2015, p.23). Following two decades of reform, the continent has now emerged one of the fastest-growing economic regions, shifting public health focus toward non-communicable diseases (NCDs) (Holt et al., 2015, p.2). Among these NCDs is anemia, which has direct and indirect economic effects as large as 4.05% of GDP (Horton & Ross, 2003, p.51). Encouraged by the rapid growth of liberalized markets, African governments and health officials are now considering local pharmaceutical production as a way to unlock the economic, social, and political benefits of improved public health. This thesis explores two hypotheses: (a) tax incentives effectively induce greater foreign direct investment in East Africa, including pharmaceutical production, and (b) local pharmaceutical production in East Africa provides better access to essential medicines like haematinics (anti-anemia drugs) as measured by anemia prevalence in children under five. We study these questions using Ethiopia and Rwanda as representative countries. Taking effect in 2012, Ethiopia’s Double Taxation Avoidance Agreement (DTAA) with India created local investment incentives via low tax rates as compared to Rwanda, which has no such agreement. We perform a difference-in-differences (DID) regression using data from Demographic and Health Surveys (DHS) to estimate the causal relationship between favorable investment conditions and anemia rates among children. Our results are inconclusive and suggest determinants of anemia are numerous and interconnected

Measuring Perceptions in Quality of Life After Camp

As children with intellectual/developmental disabilities (I/DD) begin to age out of the school system, they begin losing opportunities for socialization and recreation participation. Losing these opportunities greatly affects these individuals’ quality of life. Limitations to socialization and recreation participation are problematic and research shows it would be beneficial to provide such opportunities. This study explores how a camp environment can increase adults’ with I/DD perceptions of quality of life through providing opportunities to participate in recreation activities and socialize with other campers. Through the use of a Qualtrics survey, researchers contacted campers who attended Camp Sunlight, a camp for adults with I/DD disabilities. Researchers asked campers about their perceptions of camp and found recurring themes. After analyzing the data collected, researchers compared the themes found through the study with themes found in the literature. Study findings suggest that the camp experience does positively impact adults with I/DD perceptions of quality of life