1,416 research outputs found
A Preliminary Study of the Separation of the Copper Sulfides from Sphalerite and the Effect of Certain Reagents on Some of the Pure Copper Minerals in Synthetic Mixtures
The problem of separating the copper sulfide minerals from sphalerite, in copper - zinc ores, has been a difficult one. This is largely due to the lack of adequate research and the small amount of data obtainable on the behavior of copper and zinc sulfide minerals in flotation circuits
Land Use Changes and Pheasant Declines in Eastern South Dakota
Changes in pheasant (Phasianus colchicus) nesting habitat were investigated on Windsor Township, Brookings County, South Dakota. The population was censused, nesting densities determined, cover was mapped, and an interspersion index determined in 197 7 and 1978. Comparison to a similar study conducted in 1958 and 1959 indicated a decrease in pheasant numbers of 93% for crow counts and 94% in brood counts. Nesting densities decreased by 96%. Pheasant nests were found in about the same proportions per cover type for the two time periods. Hatching success, clutch size, rates of abandonment, and nest destruction were also similar. Nesting habitat occurred on 70% of the study area in 1958, 62% in 1959, 74% in 197 7, and 66% in 1978. The mean field size was 6.7 ha in 1958, 6.9 ha in 1959, 10.2 ha in 197 7, and 8.0 ha in 1978. The interspersion index decreased by 4% from 1958-59 to 197 7-78. Although land use changes have resulted in reduction of habitat in twenty years the amount of habitat reduction does not compare to the reduction in pheasant numbers. Factors such as cover quality, which could not be measured quantitatively, may be more responsible for decreasing the pheasant population in eastern South Dakota than cover quantity
The Methyltransferases PRMT4/CARM1 and PRMT5 Control Differentially Myogenesis in Zebrafish
In vertebrates, skeletal myogenesis involves the sequential activation of myogenic factors to lead ultimately to the differentiation into slow and fast muscle fibers. How transcriptional co-regulators such as arginine methyltransferases PRMT4/CARM1 and PRMT5 control myogenesis in vivo remains poorly understood. Loss-of-function experiments using morpholinos against PRMT4/CARM1 and PRMT5 combined with in situ hybridization, quantitative polymerase chain reaction, as well as immunohistochemistry indicate a positive, but differential, role of these enzymes during myogenesis in vivo. While PRMT5 regulates myod, myf5 and myogenin expression and thereby slow and fast fiber formation, PRMT4/CARM1 regulates myogenin expression, fast fiber formation and does not affect slow fiber formation. However, our results show that PRMT4/CARM1 is required for proper slow myosin heavy chain localization. Altogether, our results reveal a combinatorial role of PRMT4/CARM1 and PRMT5 for proper myogenesis in zebrafish
SAGA: Sparse And Geometry-Aware non-negative matrix factorization through non-linear local embedding
International audienceThis paper presents a new non-negative matrix factorization technique which (1) allows the decomposition of the original data on multiple latent factors accounting for the geometrical structure of the manifold embedding the data; (2) provides an optimal representation with a controllable level of sparsity; (3) has an overall linear complexity allowing handling in tractable time large and high dimensional datasets. It operates by coding the data with respect to local neighbors with non-linear weights. This locality is obtained as a consequence of the simultaneous sparsity and convexity constraints. Our method is demonstrated over several experiments, including a feature extraction and classification task, where it achieves better performances than the state-of-the-art factorization methods, with a shorter computational time
A fast GNU method to draw accurate scientific illustrations for taxonomy
Nowadays only digital figures are accepted by the most important journals of taxonomy. These may be produced by scanning conventional drawings, made with high precision technical ink-pens, which normally use capillary cartridge and various line widths. Digital drawing techniques that use vector graphics, have already been described in literature to support scientists in drawing figures and plates for scientific illustrations; these techniques use many different software and hardware devices. The present work gives step-by-step instructions on how to make accurate line drawings with a new procedure that uses bitmap graphics with the GNU Image Manipulation Program (GIMP). This method is noteworthy: it is very accurate, producing detailed lines at the highest resolution; the raster lines appear as realistic ink-made drawings; it is faster than the traditional way of making illustrations; everyone can use this simple technique; this method is completely free as it does not use expensive and licensed software and it can be used with different operating systems. The method has been developed drawing figures of terrestrial isopods and some examples are here given
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New Pump and Treat Facility Remedial Action Work Plan for Test Area North (TAN) Final Groundwater Remediation, Operable Unit 1-07B
This remedial action work plan identifies the approach and requirements for implementing the medical zone remedial action for Test Area North, Operable Unit 1-07B, at the Idaho National Engineering and Environmental Laboratory (INEEL). This plan details management approach for the construction and operation of the New Pump and Treat Facility. As identified in the remedial design/remedial action scope of work, a separate remedial design/remedial action work plan will be prepared for each remedial component of the Operable Unit 1-07B remedial action. This work plan was originally prepared as an early implementation of the final Phase C remediation. At that time, The Phase C implementation strategy was to use this document as the overall Phase C Work Plan and was to be revised to include the remedial actions for the other remedial zones (hotspot and distal zones). After the completion of Record of Decision Amendment: Technical Support Facility Injection Well (TSF-05) and Surrounding Groundwater Contamination (TSF-23) and Miscellaneous No Action Sites, Final Remedial Action, it was determined that each remedial zone would have it own stand-alone remedial action work plan. Revision 1 of this document converts this document to a stand-alone remedial action plan specific to the implementation of the New Pump and Treat Facility used for plume remediation within the medical zone of the OU 1-07B contaminated plume
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Next Generation Nuclear Plant System Requirements Manual
System Requirements Manual for the NGNP Projec
Une augmentation du calcium intracellulaire contrôle l’expression d’une arginine N-méthyl-transférase impliquée dans la détermination neurale chez l’embryon d’amphibien
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