2,603 research outputs found
Mineral reconnaissance at the Highland boundary with special reference to the Loch Lomond and Aberfoyle areas
Serpentinite bodies at the Highland Boundary in
the Loch Lomond and Aberfoyle areas are
extensively altered to magnesite-quartz and
ferroan-dolomite-quartz rocks. Silicification was
probably initiated before conversion to carbonate.
Relict textures indicate that the serpentinites were
derived from peridotitic precursors, but one
unaltered ultrabasic sample comprises mainly
chromian diopside. Chromite geochemistry and
hornblende-schist mineralogy rein force the ophiolitic
character of the serpentinite-spilite-blackshale-
chcrt assemblage of the Highland Border.
Magnetic and VLF traverses across the Highland
Boundary fracture-zone near Helensburgh
identified several anomalous zones. One may be
due to a concealed serpentinitic sheet.
The most mineralised serpentinite body
showed chromium values in the range 1000 to
3035 ppm. Such concentrations arc not encouraging
for the small serpentinites at Loch Lomond
and Aberfoyle, but may be significant regarding
larger serpentinites elsewhere at the Highland
Border
The quantitative soil pit method for measuring belowground carbon and nitrogen stocks
Many important questions in ecosystem science require estimates of stocks of soil C and nutrients. Quantitative soil pits provide direct measurements of total soil mass and elemental content in depth-based samples representative of large volumes, bypassing potential errors associated with independently measuring soil bulk density, rock volume, and elemental concentrations. The method also allows relatively unbiased sampling of other belowground C and nutrient stocks, including roots, coarse organic fragments, and rocks. We present a comprehensive methodology for sampling these pools with quantitative pits and assess their accuracy, precision, effort, and sampling intensity as compared to other methods. At 14 forested sites in New Hampshire, nonsoil belowground pools (which other methods may omit, double-count, or undercount) accounted for upward of 25% of total belowground C and N stocks: coarse material accounted for 4 and 1% of C and N in the O horizon; roots were 11 and 4% of C and N in the O horizon and 10 and 3% of C and N in the B horizon; and soil adhering to rocks represented 5% of total B-horizon C and N. The top 50 cm of the C horizon contained the equivalent of 17% of B-horizon carbon and N. Sampling procedures should be carefully designed to avoid treating these important pools inconsistently. Quantitative soil pits have fewer sources of systematic error than coring methods; the main disadvantage is that because they are time-consuming and create a larger zone of disturbance, fewer observations can be made than with cores
Investigation of stratiform sulphide mineralisation at Meall Mor, South Knapdale, Argyll
A co-ordinated geochemical-geophysical-geological investigation of copper
mineralisation in the Meal1 ?46r area, South Knapdale, Argyll was carried 0th
in 1976 and followed by a drilling programme of 3 shallow holes in early 1977.
The mineralisation occursin a zone of weak stratiform sulphide mineralisation
(the pyrite zone) with a strike length of 1Okm in the Upper &ins Quartz&e
of the Middle Dalradian.
The geochemical drainage survey showed the existence of a strongly anomalous
distribution of Cu and Sb in the Abhainn Srathain draining south from .
Meal1 M&- and detailed soil sampling over the pyrite zone outlined a broad
area enriched in copper. Deeper soil sampling confirmed the anomalously
high copper values and a coincident IP anomaly was found stretching from
Meal1 M& south to the old mine workings on Abhainn Srathain, and is probably
caused by a local enrichment of pyrite and chalcopyrite within the pyrite
zone.
Three boreholes were drilled; two on coincident geochemical and geophysical
anomalies, and the third beneath the old mines at Abhainn Srathain. Copper
values in the first two holes range up to 0.24% Cu over 4.27m, but up to
1.06% Cu over 2.67m in the third and this enrichment may be related to a
later remobilisation of the disseminated chalcopyrite. The results of subsequent
drilling at two other sites are given in Appendix III
Changes in Field Stored large Hay Packages
During a 3-year period, 12 large hay packages (six alfalfa, six prairie hay) were made using either Haybuster or Hesston process and stored from 8 to 29 months. Stacks were core sampled at periodic intervals for physical (moisture, density) and quality parameters (crude protein, neutral-detergent fiber, Crampton and Maynard cellulose, acid-detergent fiber, acid-detergent lignin, ash and in vitro dry matter digestibility. The hay package storage areas were located in north-central South Dakota
Implementing Professional Development in Science Using Coaching: An Action Research Study
This action research utilized a mix method approach where qualitative and quantitative data were collected. The research study sought to explore if sustained professional development through coaching was done with teachers to enact problem-based learning would transform teachers’ praxis. In addition, the researcher examined what were the factors that contributed to teachers’ inability to transfer learning from a traditional workshop setting to implementing the knowledge gained to their classrooms. The action research consisted of two major stages, namely the needs assessment and the action research cycle. It was imperative that the researcher explore the local setting to ascertain the perceptions of teachers and look at data to determine the needs. From the needs assessment the researcher co-constructed and implemented an intervention to train teacher-participants about problem-based learning as well as conducted awareness sessions about peer coaching and what should be expected during the research study. The researcher collaborated with teacher-participants during the coaching model as they embraced co-planning, modeling, and guidance for enactment. Upon the completion of the intervention, the action research cycle began with teachers of science. Throughout the research study, a key feature was a critical reflection by the teachers as well as the researcher. Students doing the problem-based learning cycles were encouraged to do reflection, as this was a best practice for problem-based learning theory. The researcher was guided by the review of the data in Iteration 1 to make adjustments for Iteration 2; data were further analyzed in Iteration 2 after the science participants were completed, this informed changes that were made in Iteration 3. The research concluded with an ethnographic reflection of the transformation process that indicated the use of coaching as a professional development initiative for the enactment of a new instructional strategy. In addition, the overall effect that this had on the researcher’s praxis and research skills
Influence of previous crops and nematicide treatments on root lesion nematode populations and crop yields
Nous avons étudié au champ l'influence du précédent cultural, de la séquence culturelle et de traitements à l'aldicarbe sur les populations de nematodes des nodosités et sur les rendements de diverses cultures à l'île-du Prince-Édouard. La culture précédente a eu le plus grand impact sur le nombre de nematodes. Les séquences des cultures ont parfois eu une influence sur les populations de nematodes des nodosités (principalement Pratylenchus penetrans) et sur les rendements. Dans les champs commerciaux d'orge (Hordeum vulgare), les nematodes des nodosités étaient plus nombreux lorsque l'orge suivait une culture combinée de trèfle rouge (Trifolium pratense) et de fléole (Phleum pratense) et les nematodes du rabougrissement (Tylenchorynchus spp., principalement T. dubiuset Merlinius spp.) étaient plus nombreux quand l'orge était semée pendant deux années consécutives. La masse de la matière sèche combinée du feuillage et du grain était plus importante lorsque l'orge était semée auprès des pommes de terre (Solanum tuberosum) et cette masse était plus faible avec deux cultures successives d’orge ou avec un mélange de trèfle rouge et de fléole. En conditions expérimentales au champ, les populations de nématodes des nodosités étaient plus élevées dans les racines d’orge lorsque celle-ci était cultivée après des pommes de terre et les rendements en grain étaient plus faibles lorsque l’orge était cultivée pendant deux années consécutives. Les changements dans les populations de nématodes chez la pomme de terre n’étaient pas associés aux séquences débutant avec le blé (Triticum aestivum) ou l’orge que dans les séquences débutant avec les pommes de terre ou le soya (Glycine max). L’aldicarbe a réduit le nombre de nématodes des nodosités en plus d’accroître les rendements en pommes de terre et en soya.A field study assessing the influence of the previous crop, the crop sequence, and aldicarb treatments on root lesion nematode populations and crop yields was carried out in Prince-Edward-Island, Canada. The most recent crop had the greatest impact on nematode numbers. The crop sequences had an influence in some cases on root lesion nematode populations (primarily Pratylenchus penetrans) and on crop yields. In commercial barley (Hordeum vulgare) fields, root lesion nematodes in roots were greatest when barley followed a red clover (Trifolium pratense) timothy (Phleum pratense) ley, and stunt nematodes (Tylenchorhynchus spp., primarily T. dubius, and Merlinius spp.) were more common when barley followed barley. The combined dry weight of foliage and grain was larger when barley was planted after potato (Solanumtuberosum) and smaller when barley followed barley or a red clover-timothy mixture. Under experimental field conditions, root lesion nematode populations were largest in barley roots when barley followed potato and grain yields were smallest when barley followed barley. Changes in nematode populations in potato were not associated with crop sequences. Potato tuber yields were higher in the sequences that began with wheat (Triticum aestivum) or barley than in the sequences that began with potato or soybean (Glycine max). Aldicarb reduced the numbers of root lesion nematodes in roots with concomitant yield increases in potato and soybean
Relativistic many-body calculations of electric-dipole matrix elements, lifetimes and polarizabilities in rubidium
Electric-dipole matrix elements for ns-n'p, nd-n'p, and 6d-4f transitions in
Rb are calculated using a relativistic all-order method. A third-order
calculation is also carried out for these matrix elements to evaluate the
importance of the high-order many-body perturbation theory contributions. The
all-order matrix elements are used to evaluate lifetimes of ns and np levels
with n=6, 7, 8 and nd levels with n=4, 5, 6 for comparison with experiment and
to provide benchmark values for these lifetimes. The dynamic polarizabilities
are calculated for ns states of rubidium. The resulting lifetime and
polarizability values are compared with available theory and experiment.Comment: 8 pages, 2 figure
Non-invasive measurement of a metabolic marker of infant brain function
While near-infrared spectroscopy (NIRS) haemodynamic measures have proven to be vastly useful in investigating human brain development, the haemodynamic response function (HRF) in infants is not yet fully understood. NIRS measurements of the oxidation state of mitochondrial enzyme cytochrome-c-oxidase (oxCCO) have the potential to yield key information about cellular oxygen utilisation and therefore energy metabolism. We used a broadband NIRS system to measure changes in oxCCO, in addition to haemodynamic changes, during functional activation in a group of 33 typically developing infants aged between 4 and 6 months. The responses were recorded over the right temporal lobe while the infants were presented with engaging videos containing social content. A significant increase in oxCCO was found in response to the social stimuli, with maximum increase of 0.238 ± 0.13 μM. These results are the first reported significant change in oxCCO in response to stimulus-evoked activation in human infants and open new vistas for investigating human infant brain function and its energy metabolism
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