Microminiature gas chromatographic column

Techniques commonly used for fabrication of integrated circuits are utilized to produce long capillary tubes for microminiature chromatographs. Method involves bonding of flat silicon plate to top of spirally grooved silicon chip to close groove and form capillary column

Dual mode laser velocimeter

Described is a laser Doppler velocimeter (LDV) which is capable of operating with a small focus diameter for analyzing fluid flows at low velocity with high spatial resolution, or with a larger focus diameter to measure fluid flows at higher velocities accurately. More particularly, this is an LDV in which a simple reversal of a lens pair will allow it to operate in the two focus diameter modes

Gas chromatograph injection system

An injection system for a gas chromatograph is described which uses a small injector chamber (available in various configurations). The sample is placed in the chamber while the chamber is not under pressure and is not heated, and there is no chance of leakage caused by either pressure or heat. It is injected into the apparatus by changing the position of a valve and heating the chamber, and is volatilized and swept by a carrier gas into the analysis apparatus

Investigating the viability of yeast expressing histone from extrachromosomal DNA : progress in construction of a plasmid bearing one copy of each yeast histone gene

Much of the current information on histones has been based on in vitro studies. The original goal of this research was to construct a mutant strain of Saccharomyces cerevisiae containing all chromosomal copies of the yeast histone genes made nonfunctional. This project would demonstrate whether such a strain could be rescued by a plasmid carrying the wild-type copies of the four core histone genes. Furthermore, this yeast strain construct would allow future investigations to take advantage of histone mutant analysis in vivo. The critical step in beginning this work was the construction of a plasmid which contained the genes coding for histones H2A, H2B, H3, and H4. Construction of this plasmid proved difficult to complete due to such problems as using a nontransformable bacterial single colony, utilizing a plasmid which was subsequently found to be in fact another plasmid. This thesis describes specific methods used for transformation, partial digestion and DNA recovery techniques which were attempted and the results of these attempts. The approaches developed should simplify future construction of the plasmid and contribute to further studies investigating the viability of yeast using histone expressed from extrachromosomal DNA

Nondispersive infrared analyzer for specific gases in complex mixtures

Analyzer identifies and measures particular diatomic or polyatomic gases in complex gas mixtures. Mixing of absorption effects on light energy passing through gases to photodetector produces a signal component that is related to the absorption caused by reference-gas component in unknown gas mixture

High School Achievement in Maine: Where You Come From Matters More Than School Size and Expenditures

Fern Desjardins and Gordon Donaldson report on their research examining the relationship between academic achievement in Maine’s public high schools and school size, per-pupil operating costs, and socioeconomic status. Using aggregated Maine Educational Assessment (MEA) scores, their study confirmed previous research that socioeconomic status (using both family and community measures) is the most important factor associated with achievement, while school size is not a critical factor. Additionally, the authors found that per-pupil operating costs are higher in the state’s largest and smallest high schools. The authors suggest that the creation of larger districts and larger schools, as supported by recent state policies, will not necessarily mitigate inequities in student achievement resulting from family and community socioeconomic status, and may not yield the desired cost savings

Photosynthesis-irradiance responses in the Ross Sea, Antarctica: a meta-analysis

A meta-analysis of photosynthesis-irradiance measurements was completed using data from the Ross Sea, Antarctica, using a total of 417 independent measurements. P-m(B), the maximum, chlorophyll-specific, irradiancesaturated rate of photosynthesis, averaged 1.1 +/- 0.06 mu gC (mu g Chl)(-1) h(-1). Light-limited, chlorophyll-specific photosynthetic rates (alpha(B)) averaged 0.030 +/- 0.023 mu gC (mu g Chl)(-1) h(-1) (mu mol quanta m(-2) s(-1))(-1). Significant variations in P-m(B) and alpha(B) were found as a function of season, with spring maximum photosynthetic rates being 60% greater than those in summer. Similarly, alpha values were 48% greater in spring. There was no detectable effect of sampling location on the photosynthetic parameters, and temperature and macronutrient (NO3) concentrations also did not have an influence. However, irradiance and carbon dioxide concentrations, when altered under controlled conditions, exerted significant influences on photosynthetic parameters. Specifically, reduced irradiance resulted in significantly decreased P-m(B) and increased alpha(B) values, and increased CO2 concentrations resulted in significantly increased P-m(B) and alpha(B) values. Comparison of photosynthetic parameters derived at stations where iron concentrations were above and below 0.1nM indicated that reduced iron levels were associated with significantly increased P-m(B) values, confirming the importance of iron within the photosynthetic process. No significant difference was detected between stations dominated by diatoms and those dominated by the haptophyte Phaeocystis antarctica. The meta-analysis confirms the photosynthetic rates predicted from global analyses that are based solely on temperature and irradiance availability, but suggests that, for more accurate predictions of productivity in polar systems, a more detailed model that includes temporal effects of photosynthetic parameters will be required

Fusing Educational Reform Policy and Action: Assuring the Development of Local Leaders

School change does not happen in a vacuum. It requires initiative and leadership. Because Maine\u27s educational system features a strong local control component, successful educational change requires development of local leadership. George Marnik and Gordon Donaldson report on the Maine Academyfor School Leaders, an educational leadership development project in which they were involved. Among other things, the researchers learned that successful educational change is not likely to result from a one-size-fits-all state policy. Rather, successful reform occurs one individual at a time, one school at a time

A statistical investigation of the effects contributed by tape recorders and by wow and flutter of magnetic tape on the accuracy of a telemetry system Technical report no. 15

Effects contributed by tape recorders and by wow and flutter of magnetic tape on accuracy of telemetry syste