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Response of Artemisia tridentata ssp. wyomingensis and Stipa thurberiana to nitrogen amendments
The effect of nitrogen on influencing the competitive balance between a shrub, Artemisia tridentata ssp. wyolningensis (ARTRW) and a perennial grass Stipa
thurberiana (STTH) in a sagebrush steppe community was determined. Nitrogen levels were altered on 5x5 in plots by applying 4.5 gun2 of nitrogen in the form of ammonium
or nitrate, or 45 gum2 of sugar. Treatments were compared with untreated control plots. Plant growth, production, leaf nitrogen content, soil water content and soil nitrogen
content were measured throughout growing season of 1987. Both forms of nitrogen, ammonium and nitrate, increased shoot densities, shoot length, ephemeral leaf number per terminal bud, reproductive shoots and leaf nitrogen content in ARTRW. Additions of nitrogen significantly increased
tiller density, reproductive shoots, biomass and leaf nitrogen content in STTH. Nitrate provided the greatest increase in reproductive shoots, for the two forms of
nitrogen. Reproductive tiller density in STTH increased 66% for ammonium and 250% for nitrate, and 56% for ainnionium and 193% for nitrate in ARTRW over control. Nitrogen form
did not appear to favor either the shrub or grass. Although both species responded positively to increases in available nitrogen, leaf area, above ground net annual
primary productivity and nitrogen uptake increased in ARTRW to a greater magnitude than STTH. Addition of sugar did not appear to decrease soil nitrogen availability comparing to control treatment in this research. Environmental conditions causing temporary increases in animonium and or
nitrate may drive the successional process towards a ARTRW dominated site
Improving Formwork Engineering Using the Toyota Way
Construction is a labor-intensive industry with formwork engineering requiring a disproportionate amount of labor and costs. Formwork accounts for approximately one-third of the cost of reinforced concrete construction, partly because traditional formwork processes frequently result in delivery delays and material waste. The purpose of this research is to adapt production concepts pioneered by Toyota (the “Toyota Way”) to improve formwork engineering. The Toyota Way of production consists of four tiers of management philosophy, known as the “4Ps” model. This research adopts the 4Ps as steps for formwork improvement. The first step, “establishing long term vision,” emphasizes long term considerations for formwork improvement. Step two, “establishing value streams,” reviews formwork flows and eliminates wastage. The third step, “developing the crew,” forms mold workers as a team. The final step is “developing a culture of continuous improvement” that provides a basis for constant review and provides a basis for continuous progress. The present research used the Toyota Way to improve formwork engineering. The improvements include reductions in resource waste and increases in operational value. In the long run, the proposed model could provide a learning and growth platform for individuals, the business unit, and the company’s extended network of partners. It could also serve to spur innovative thinking in the improvement of formwork engineering
Porocarcinoma in situ showing follicular differentiation: A case report
AbstractPoroid neoplasm is a skin appendage tumor that has both benign and malignant counterparts. It has traditionally been regarded as of eccrine origin and has four types: intraepidermal poroma (hidroacanthoma simplex), poroma, dermal duct tumor, and poroid hidradenoma. Here we describe the case of a 64-year-old woman who had a verrucous, erythematous to brownish tumor on her left buttock for many years. Histopathology revealed an intra-epidermal poroid tumor with both benign and malignant parts. The benign part had intra-epidermal nests of poroid cells, which were smaller, monomorphic and sharply marginated from adjacent keratinocytes. The malignant part showed similar cell types, but had a higher nuclear/cytoplasmic ratio, pleomorphism, and prominent mitoses. Ductal structures were noted in neoplastic cells and an epithelial membrane antigen stain was strongly positive. Interestingly, peripheral palisading and primitive follicular germ formation were also observed in the neoplasm, which suggests follicular differentiation. We made a final diagnosis of porocarcinoma in situ with follicular differentiation, which may support the folliculosebaceous–apocrine unit theory, but a tumor with such a combination has not been described before
Seismic Anisotropy of the Upper Crust in the Mountain Ranges of Taiwan from the TAIGER Explosion Experiment
Taiwan is known as a strongly anisotropic region observed from SKS 1 - 2 s delay time and other teleseismic phases. An estimate of the crustal contribution to the total anisotropy from the foliated Central Range is essential to understanding the overall teleseismic results. We used P wave arrivals from the dense seismic arrays deployed during the TAIGER active source experiments and the permanent broadband seismic stations to determine the crustal anisotropy. From the arrival time analysis as a function of azimuth, we detected a clear cos(2£c) pattern. The strength of the crustal anisotropy (0 - 15 km depth) reaches 8 - 10% and the fast direction azimuth is around 35 - 43¢X for the overall mountain ranges. The anisotropic variations from the central to the north are found in detail. The results could indicate that the upper crustal delay time contribution of teleseismic shear waves reaches up to 0.45 s. The geological data at the surface and geophysical observations imply a coherent deformation from the surface to the lower crust or even down to the upper mantle
KINETIC ANALYSIS OF THE UPPER EXTREMITY BETWEEN DIFFERENT STANCES IN TENNIS TWO-HANDED BACKHAND
INTRODUCTION: Now the tennis players could explore more racket capabilities through the change of racket materials and design. The open stance comes out in modern tennis relative to the traditional square stance. This study was conducted to analyze the upper extremity joint forces and moments between the different stances in advanced and intermediate athletes, who separated from ITN rating system, during two-handed stroke
Impact of Aerosols on Convective Clouds and Precipitation
Aerosols are a critical factor in the atmospheric hydrological cycle and radiation budget. As a major reason for clouds to form and a significant attenuator of solar radiation, aerosols affect climate in several ways. Current research suggests that aerosol effects on clouds could further extend to precipitation, both through the formation of cloud particles and by exerting persistent radiative forcing on the climate system that disturbs dynamics. However, the various mechanisms behind these effects, in particular the ones connected to precipitation, are not yet well understood. The atmospheric and climate communities have long been working to gain a better grasp of these critical effects and hence to reduce the significant uncertainties in climate prediction resulting from such a lack of adequate knowledge. The central theme of this paper is to review past efforts and summarize our current understanding of the effect of aerosols on precipitation processes from theoretical analysis of microphysics, observational evidence, and a range of numerical model simulations. In addition, the discrepancy between results simulated by models, as well as that between simulations and observations will be presented. Specifically, this paper will address the following topics: (1) fundamental theories of aerosol effects on microphysics and precipitation processes, (2) observational evidence of the effect of aerosols on precipitation processes, (3) signatures of the aerosol impact on precipitation from large-scale analyses, (4) results from cloud-resolving model simulations, and (5) results from large-scale numerical model simulations. Finally, several future research directions on aerosol - precipitation interactions are suggested
Cost and Benefit Analysis of Line Arresters for a 69kV Transmission System in Taiwan
This paper presents a systematical evaluation experience on the performance and economic studies of line arresters for a 69 kV transmission system in Taiwan. The transient over-voltage phenomenon in high voltage transmission lines under lightning by using the Electro-Magnetic Transients Program (EMTP) package is well modeled and analyzed. The modeling for the simulated system including lightning, transmission line, transmission tower and line arrester are all considered to have more practical results. The cost and benefit evaluation for line arresters installation  is then conducted to provide a reasonable suggestion for lightning protection.  The performance of line arresters is evaluated by considering different installation schemes and lightning currents. Finally, a Taiwan’s experience is illustrated from both of the cost and benefit points of view
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