REDUCING SYSTEM BIAS AND SPECIFICATION ERROR IN MICRO-IMPLAN

Community/Rural/Urban Development,

WATER USE COMPONENTS OF A REGIONAL ACCOUNTS AND SIMULATION SYSTEM

Resource /Energy Economics and Policy,

Evaluation of alternative market organizations in a simulated livestock-meat economy

The economic effects of alternative forms of market organization can be studied by direct observation or by experimenting with a simulated economy. The experimental approach in the study of market behavior is a relatively new but important technique for the analysis of many policy issues in American agriculture. Experimenting on a simulated system is not an analytical approach confined to academic issues; it has its counterpart, for example, in the engineering fields. Major engineering installations often are based on studies involving the use of models in simulated situations; the experimental results provide a basis for more accurately anticipating the actual performance of a dam, a bridge or a vehicle under different conditions. Similarly, simulation in economic research involves model building and manipulation that makes possible. the telescoping of years of actual experience into a matter of minutes and a few dollars worth of computer time

Goosecoid acts cell autonomously in mesenchyme-derived tissues during craniofacial development

Mice homozygous for a targeted deletion of the homeobox gene Goosecoid (Gsc) have multiple craniofacial defects. To understand the mechanisms responsible for these defects, the behavior of Gsc-null cells was examined in morula aggregation chimeras. In these chimeras, Gsc-null cells were marked with beta-galactosidase (beta-gal) activity using the ROSA26 lacZ allele. In addition, mice with a lacZ gene that had been introduced into the Gsc locus were used as a guide to visualize the location of Gsc-expressing cells. In Gsc-null\u3c-\u3ewild-type chimeras, tissues that would normally not express Gsc were composed of both Gsc-null and wild-type cells that were well mixed, reflecting the overall genotypic composition of the chimeras. However, craniofacial tissues that would normally express Gsc were essentially devoid of Gsc-null cells. Furthermore, the nasal capsules and mandibles of the chimeras had defects similar to Gsc-null mice that varied in severity depending upon the proportion of Gsc-null cells. These results combined with the analysis of Gsc-null mice suggest that Gsc functions cell autonomously in mesenchyme-derived tissues of the head. A developmental analysis of the tympanic ring bone, a bone that is always absent in Gsc-null mice because of defects at the cell condensation stage, showed that Gsc-null cells had the capacity to form the tympanic ring condensation in the presence of wild-type cells. However, analysis of the tympanic ring bones of 18.5 d.p.c. chimeras suggests that Gsc-null cells were not maintained. The participation of Gsc-null cells in the tympanic ring condensation of chimeras may be an epigenetic phenomenon that results in a local environment in which more precursor cells are present. Thus, the skeletal defects observed in Gsc-null mice may reflect a regional reduction of precursor cells during embryonic development

Simulation of regional product and income with emphasis on Iowa, 1954-1974

To simulate the growth of a region\u27s product and income is to create the data that describe the evolution of a regional economic system. In this study the data pertain to the Iowa economy for the 20-year period - 1954 to 1974. They are presented for two primary purposes - to illustrate (a) the effects of major market and technological trends on a state or regional economy and (b) the uses of social accounting data in state or regional development and planing. Estimates of the gross Iowa product are presented to show its changing composition over the 1954-74 period. In addition, a system of economic relationships is used to generate year-to-year changes in specific components of Iowa\u27s gross product. The Iowa data show the principal structural features of the state\u27s economy. In 1954, for example, the gross Iowa product (i.e., the value added by economic activity in Iowa) was 5.6 billion dollars, of which 4.5 billion dollars was in the form of personal income payments. Thus, the 1954 gross state product of $2,090 per capita was sufficient to allow for an average personal income of$1,690, given a total Iowa population of 2,665,000. By 1974, the Iowa gross product will reach 9.5 billion dollars (in constant 1954 dollars) - an increase over the 20-year period of 2.7 percent per year, compounded annually - according to the benchmark projections. Total population in 1974 is estimated at 2,852,400, an increase of only 1/3 percent per year. Per-capita personal income would reach 2,560 dollars per person, while projected gross investment would reach 2.2 billion dollars

Integer programming for optimized facility location

This thesis presents a general model for the location problem based on integer linear programming with fixed charges. The location problem is concerned with choosing locations for facilities throughout a particular region or area in such a way that total costs and expenses incurred are minimized. Although the location problem presented is basically of second degree, a transformation is used to convert the problem to linear form. Following the development of the general model, this particular method is applied to a problem of determining the optimum size, location, and combination of incinerators and/or power plants to be installed for the disposal of wood waste. The determination of fixed charges and other relative costs becomes increasingly more complex as deviations from the general model occur

Automation In The Design Of Asynchronous Sequential Circuits

Sequential switching circuits are commonly classified as being either synchronous or asynchronous. Clock pulses synchronize the operations of the synchronous circuit. The operation of an asynchronous circuit is usually assumed to be independent of such clocks. The operating speed of an asynchronous circuit is thus limited only by basic device speed. One disadvantage of asynchronous circuit design has been the complexity of the synthesis procedures for large circuits

A Complement Receptor C5a Antagonist Regulates Epithelial to Mesenchymal Transition and Crystallin Expression After Lens Cataract Surgery in Mice

Purpose: To evaluate the effects of complement employing a mouse model for secondary cataract. Methods: The role of complement receptor C5a (CD88) was evaluated after cataract surgery in mice. An antagonist specific to C5a receptor was administered intraperitoneally to mice. Epithelial to mesenchymal transition (EMT) was evaluated by alpha-smooth muscle actin (α-SMA) staining and proliferation by bromodeoxyuridine (5-bromo-2\u27- deoxyuridine, BrdU) incorporation. Gene expression patterns was examined by microarray analysis and quantitative polymerase chain reaction (QPCR). Results: We found that administration of a C5aR antagonist in C57BL/6J mice decreases EMT, as evidenced by α-SMA expression, and cell proliferation. Gene expression by microarray analysis reveals discreet steps of gene regulation in the two major stages that of EMT and lens fiber differentiation in vivo. A hallmark of the microarray analysis is that the antagonist seems to be a novel stage-specific regulator of crystallin genes. At week two, which is marked by lens fiber differentiation genes encoding 12 crystallins and 3 lens-specific structural proteins were severely down-regulated. Conclusions: These results suggest a possible therapeutic role of an antagonist to C5aR in preventing secondary cataracts after surgery. Also these results suggest that crystallin gene expression can be regulated by pro-inflammatory events in the eye

The effect of a concurrent cognitive task on cortical potentials evoked by unpredictable balance perturbations

BACKGROUND: Although previous studies suggest that postural control requires attention and other cognitive resources, the central mechanisms responsible for this relationship remain unclear. To address this issue, we examined the effects of altered attention on cortical activity and postural responses following mechanical perturbations to upright stance. We hypothesized that cortical activity would be attenuated but not delayed when mechanical perturbations were applied during a concurrent performance of a cognitive task (i.e. when attention was directed away from the perturbation). We also hypothesized that these cortical changes would be accompanied by alterations in the postural response, as evidenced by increases in the magnitude of anteroposterior (AP) centre of pressure (COP) peak displacements and tibialis anterior (TA) muscle activity. Healthy young adults (n = 7) were instructed to continuously track (cognitive task) or not track (control task) a randomly moving visual target using a hand-held joystick. During each of these conditions, unpredictable translations of a moving floor evoked cortical and postural responses. Scalp-recorded cortical activity, COP, and TA electromyographic (EMG) measures were collected. RESULTS: Results revealed a significant decrease in the magnitude of early cortical activity (the N1 response, the first negative peak after perturbation onset) during the tracking task compared to the control condition. More pronounced AP COP peak displacements and EMG magnitudes were also observed for the tracking task and were possibly related to changes in the N1 response. CONCLUSION: Based on previous notions that the N1 response represents sensory processing of the balance disturbance, we suggest that the attenuation of the N1 response is an important central mechanism that may provide insight into the relationship between attention and postural control