13,574 research outputs found
Changes in the forms and availability of applied phosphate over a twelve-month period in two soils of the Manawatu-Rangitikei sand country : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science at Massey University
A feature of New Zealand agriculture is the requirement for regular applications of phosphate fertilizer to maintain high producing pastures. This is reflected in the large amounts of phosphate fertilizer sold annually, which for the 1971-72 season reached a level of 2,041,000 tonnes. The soils of the Manawatu-Rangitikei sand country, being naturally deficient in phosphate, are no exception to this requirement for regular applications of phosphate. However, these soils, especially those of the sand plains are potentially fertile. Thus trials conducted by the Department of Agriculture have shown that, on Himatangi sand, pasture production in the range 15,700-16,800 kg D.M./ha can be realized (Blackmore, pers. comm.). The need for regular, preferably at least annual, application of phosphate to these sand country soils implies a fall in the level of availability of the applied phosphate within the zone of action of the pasture roots due either to:- (i) actual loss of phosphate from this zone by leaching a distinct possibility in such light-textured soils; or (ii) a change in the soil/soil solution equilibrium distribution of phosphate as a result of changes in the nature of the fixed forms with time; or (iii) a combination of those factors. The object of the present study was to investigate the operation of these factors for two representative sand country soils, the differing moisture regime and pH status of which might be expected to exert some influence on the course of phosphate fixation. At the same time, it was hoped to reach some conclusion as to the relative sensitivity of a number of commonly used chemical "quick tests" for evaluation of phosphate availability in these soils and to determine whether changes in these values were paralleled by demonstrable changes in the forms of phosphate binding
Device for diode tuning in a stripline varactor harmonic multiplier
Stripline varactor harmonic multiplier uses a device for positioning the varactor diode with respect to the stripline circuit to obtain series resonance. The device also reduces detuning effects, due to thermal expansion, over a wide temperature range
Nitrate Concentrations of Ground Water from Limestone and Dolomitic Aquifers in the Northeastern Washington County Area, Arkansas
The Ozark Region of Arkansas is a major poultry-producing area of the United States. Large quantities of poultry waste are spread as fertilizer on thin soils of pastureland overlying limestone and dolomitic aquifers. Because these aquifers provide domestic water supplies for the rural population and are susceptible to contamination from surface water, there is concern that nitrate leached from poultry litter is polluting the ground water. In response to this concern, well water from a major poultry-producing area was compared with that from a forested area in the northeastern Washington County area, Arkansas. Although nitrate concentration of the well water from the poultry producing area (2.83 mg/L as nitrogen) is about 10 times that of springs in the forested area, it is considerably below the drinking water limits of 10 mg/L set by the U.S. Environmental Protection Agency . The shallow Boone-st. Joe aquifer contains about twice as much nitrate as the deeper Everton aquifer. Expansion of poultry production in this region requires implementation of best management practices in order to protect the ground water from nitrate pollution
Land use change detection with LANDSAT-2 data for monitoring and predicting regional water quality degradation
There are no author-identified significant results in this report
Transferable neural networks for enhanced sampling of protein dynamics
Variational auto-encoder frameworks have demonstrated success in reducing
complex nonlinear dynamics in molecular simulation to a single non-linear
embedding. In this work, we illustrate how this non-linear latent embedding can
be used as a collective variable for enhanced sampling, and present a simple
modification that allows us to rapidly perform sampling in multiple related
systems. We first demonstrate our method is able to describe the effects of
force field changes in capped alanine dipeptide after learning a model using
AMBER99. We further provide a simple extension to variational dynamics encoders
that allows the model to be trained in a more efficient manner on larger
systems by encoding the outputs of a linear transformation using time-structure
based independent component analysis (tICA). Using this technique, we show how
such a model trained for one protein, the WW domain, can efficiently be
transferred to perform enhanced sampling on a related mutant protein, the GTT
mutation. This method shows promise for its ability to rapidly sample related
systems using a single transferable collective variable and is generally
applicable to sets of related simulations, enabling us to probe the effects of
variation in increasingly large systems of biophysical interest.Comment: 20 pages, 10 figure
Hostage-taking 1754: Virginians vs Canadians
When Virginians, Canadians, and Indians clashed, the Allegheny borderlands were a new ‘muddle ground’ of fateful cultural confusions rather than an established middle ground of recognized compromises. The taking of captives was an early, significant, and portentious part of the contest. Indians who were resettling the region were familiar with traditional panis slavery, with raiding for captives in long-range blood feuds, and with trading Indian captives to Europeans. Their capture of European traders, as diplomatic gifts, was a very recent development.Colonial trade rivalries became military, and the paltry forts became sites of negotiated surrender in 1754. Before European regulars arrived in numbers, or the Anglo-French war was formally declared, colonial intruders surrendered to their Indian and colonial rivals on three occasions. Virginians surrendered their incomplete stockade at the forks of the Ohio in April. In May, Virginians and Indians ambushed a Canadian party under Ensign Jumonville, and survivors of the initial skirmish sought quarter. Within five weeks, avenging Canadians and Indians forced Virginians to surrender their aptly-named Fort Necessity.In taking prisoners and hostages in the Allegheny borderlands, colonial officers adapted and violated both European and Indian conventions, and took different approaches in dealing with the independent actions of their Indian allies. On the eve of a major war, captives and their brethren learned what distinctions had been made, and that they might well be violated.Lorsque les Virginiens, les Canadiens et les Indiens s’affrontèrent dans les régions limitrophes des Alleghenys, ils transformèrent ce territoire en une zone de funeste confusion culturelle au lieu d’en faire un terrain de concessions mutuellement respectées. Faire des prisonniers est très tôt devenu un enjeu important et significatif. Les Indiens qui repeuplaient la région pratiquaient traditionnellement l’esclavage des Panis; ils organisaient des incursions pour faire des prisonniers dans le cadre de querelles sanglantes menées loin en territoire ennemi, et ces prisonniers indiens servaient de monnaie d’échange avec les Européens. La capture de commerçants européens, comme cadeaux diplomatiques, était une stratégie toute récente.Les rivalités commerciales entre les colonies dégénérèrent en conflits militaires, et les forts dérisoires des deux partis firent l’objet d’une reddition négociée en 1754. Avant que les troupes régulières européennes arrivent en grand nombre et que la guerre franco-anglaise ne soit officiellement déclarée, les colons des deux camps adverses et leurs alliés indiens s’étaient affrontés à trois reprises : en avril, les Virginiens, battus, avaient dû céder leur palissade incomplète érigée au confluent de l’Ohio; en mai, les Virginiens et les Indiens avaient tendu une embuscade à un détachement de Canadiens commandé par l’officier de Jumonville, et les survivants de la première escarmouche avaient demandé quartier. Moins de cinq semaines plus tard, les Canadiens et leurs alliés indiens prenaient leur revanche et forçaient les Virginiens à rendre leur petit fort, le bien-nommé Fort Necessity.En faisant des prisonniers et en prenant des otages dans la région des Alleghenys, les officiers coloniaux adaptaient et violaient les conventions européennes et indiennes; ils cherchaient à s’ajuster aux actions indépendantes de leurs alliés indiens. À la veille d’une guerre majeure, les captifs et leurs camarades d’infortune apprirent que les distinctions qui avaient été faites pourraient très bien être violées
Completion Report: Arkansas State Pesticides in Ground Water Monitoring Project Phase V: Vulnerable areas in Jackson, Monroe, Lawrence and Lonoke Counties
In 1996, sixty-seven water samples were drawn from 65 wells, including 62 new wells and 3 wells sampled previously . One Woodruff County well and two Pulaski County wells were resampled. Thirty-two samples were drawn from 30 wells in Monroe County (well #1 was sampled 3 times during this phase) . Ten wells in Jackson County, 12 wells in Lawrence County and 10 wells in Lonoke were also tested (Figures 1-5) . With the completion of Phase V, the number of wells tested has risen to 231 with a total of 258 samples analyzed . Initially, the wells were tested for 13 pesticides and ni~rate. Two more pesticides, aldicarb and carbofuran were added to the analyte list during Phase V. The analyte list is shown in Table 3 . All results from all the wells are listed in Appendix A. Quality control information for these data follow the results. The Phase V Quality Assurance Report is included in this document as Part II
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