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Abstract

Multiple-part manuscripts are those submitted to a journal and intended for publication as a series, usually having “Part 1,” “Part I,” … “Part N” in the title. Although some journals prohibit such submissions, other journals (including Monthly Weather Review) have no such restrictions. To examine how reviewers and editors view multiple-part manuscripts, 308 multiple-part manuscripts submitted to Monthly Weather Review from May 2001 through February 2010 were examined. For multiple-part manuscripts having reached a final decision, 67% were accepted, which was also the average acceptance rate of all manuscripts (67%). Part I manuscripts submitted alone had a lower acceptance rate (61%) than the average, whereas Part II manuscripts submitted alone had a higher acceptance rate (77%) than the average. Two-part manuscripts submitted together had an acceptance rate (67%) comparable to the average. Typical reviewer comments for Part I manuscripts submitted alone included the manuscript being too long for the available results and the author making claims in Part I that would be supported in the unseen Part II. Typical comments for Part II manuscripts submitted alone included the somewhat contradictory statements that material was unnecessarily duplicated in the two manuscripts and more repetition was needed between the two parts. For two-part manuscripts submitted together, reviewers often recommended condensing the two manuscripts and merging them into one. In some cases, editors rejected manuscripts even though no reviewer recommended rejection because the sum of all reviewers’ comments would require substantial reorganization of the manuscripts. The results of this study suggest the following recommendations for authors considering writing multiple-part manuscripts: Write manuscripts that are sensibly independent of each other, make minimal reference to unsubmitted manuscripts, and have sufficient and substantiated scientific content within each manuscript.

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Abstract  

A new digital filter has been investigated for removing low-frequency periodic noise from the output signal of hyper-pure germanium detectors (HPGe). Sources of noise examined include microphonics and simulated low-frequency noise (via input sinusoidal wave forms). In this paper, three distinctly different detector/mechanical-cooler combinations were investigated. Removal of the periodic noise induced from “outside” environmental sources, such as ground loops, is investigated using an input sinusoidal wave generator. The LFR not only improved spectral resolution across all energies in two of three detector/mechanical cooler combinations, but also removed simulated periodic noise from 100 to 3 kHz.

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Abstract  

We have developed a sequential extraction technique for determining the geochemical partitioning of Am, Pu, and U in soils and sediments. Stable element analyses were combined with radiometric measurements to determine the most probable geochemical host phases of these actinides in reference sediment IAEA-135.241 Am results indicate an association with carbonate minerals and organic matter. The extraction profile of238U was similar to that of refractory elements Al, Ti, and K.239/240Pu data suggest a fractionation of Pu into Fe-bearing phases of varying solubility. The reproducibility of the method was quite good (replicates agreed to within 10% at a 95% confidence level).

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A graphH divides a graphG, writtenH|G, ifG isH-decomposable. A graphG without isolated vertices is a greatest common divisor of two graphsG 1 andG 2 ifG is a graph of maximum size for whichG|G 1 andG|G 2, while a graphH without isolated vertices is a least common multiple ofG 1 andG 2 ifH is a graph of minimum size for whichG 1|H andG 2|H. It is shown that every two nonempty graphs have a greatest common divisor and least common multiple. It is also shown that the ratio of the product of the sizes of a greatest common divisor and least common multiple ofG 1 andG 2 to the product of their sizes can be arbitrarily large or arbitrarily small. Sizes of least common multiples of various pairsG 1,G 2 of graphs are determined, including when one ofG 1 andG 2 is a cycle of even length and the other is a star.

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Abstract  

Remote-handled transuranic nuclear waste poses a particular challenge for assaying due to the high neutron and -ray background that emanate from the non-fissile, but highly radioactive material, contained within the waste. The utilization of a Radio Frequency Quadrupole (RFQ) linac with a neutron flux of the order of 1010 n/s/4 has shown that, in principle, the differential die-away technique can be used to reliably assay this special class of nuclear waste.

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Abstract  

The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL, Oak Ridge, TN USA) provides natural-matrix human urine quality-assurance/quality-control (QA/QC) samples to radiobioassay analysis laboratories. Samples are provided to these laboratories as “single-blind” or “double-blind” unknowns, spiked with radioactive-solution standards at “low” levels (e.g., 0–250 mBq·kg−1 for alpha-emitters). Participants use the results as a tool for self-evaluation and a measure of performance. In this paper, sample preparation and the results of testing during the years 2000–2004 for the radionuclides natural uranium (U-nat), 238Pu, 239Pu, and 241Am are presented and discussed.

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Abstract  

The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL, Oak Ridge, TN USA) provides natural-matrix human urine quality-assurance/quality-control (QA/QC) samples to radiobioassay analysis laboratories. Samples are provided to these laboratories as “single-blind” or “double-blind” unknowns, spiked with radioactive-solution standards at “low” levels (e.g., 0.7–7 Bq g−1 for 3H and 0.7–7 Bq kg−1 for 90Sr). Participants use the results as a tool for self-evaluation and a measure of performance. In this paper, sample preparation and the results of testing during the years 2001–2005 for 3H and 90Sr are presented and discussed.

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Mixed population of different biotypes of C. arvense can be found in the cereal fields in Eastern Europe. Three biotypes were identified taxonomically: var. arvense; var. horridum, and var. vestitum. Out of the three identified biotypes, only var. arvense showed more sensitivity to chlorsulfuron, while the other two biotypes were less sensitive. There was no difference in the germination behaviour of the biotypes, thus all varieties can be present on the field at the same time. The less sensitive biotypes have a thicker cuticle and less stoma on the leaves than the more sensitive one. There is no significant difference between sensitive and resistant biotypes in absorption and translocation of the 14C chlorsulfuron and florasulam. Sensitivity of the ALS-enzyme was significantly reduced in the resistant biotypes, although the enzyme still functions. Since that cereal fields in Eastern Europe are infested with C. arvense biotypes with different susceptibilities to chlorsulfuron, it is important to consider resistance management when selecting herbicides. Selection pressure for ALS resistance can be reduced by including other herbicides with an alternative mode of action; as tank mixes, premixes, or separate applications.

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Species richness is a widespread measure to evaluate the effect of different management histories on plant communities and their biodiversity. However, analysing the phylogenetic structure of plant communities could provide new insights into the effects of different management methods on community assemblages and provide further guidance for conservation decisions. Heathlands require permanent management to ensure the existence of such a cultural landscape. While traditional management with grazing is time consuming, mechanical methods are often applied but their consequences on the phylogenetic community assemblages are still unclear. We sampled 60 vegetation plots in dry sandy heathlands (EU habitat type 2310) in northern Germany stratified by five different heathland management histories: fire, plaggen (turf cutting), mowing, deforestation and intensive grazing. Due to the distant relationship of vascular plants and lichens, we assembled two phylogenetic trees, one for vascular plants and one for lichens. We then calculated phylogenetic diversity (PD) and measures of phylogenetic community structure for vascular plant and lichen communities. Deforested areas supported significantly higher PD values for vascular plant communities. We found that PD was strongly correlated with species richness (SR) but the calculation of rarefied PD was uncorrelated to SR leading to a different ranking of management histories. We observed phylogenetic clustering in the lichen communities but not for vascular plants. Thus, management by mowing and intensive grazing promotes habitat filtering of lichens, while management histories that cause greater disturbance such as fire and plaggen do not seem to affect phylogenetic community structure. The set of management strategies fulfilled the goals of the managers in maintaining a healthy heathland community structure. However, management strategies that cause less disturbance can offer an additional range of habitat for other taxonomic groups such as lichen communities.

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Abstract  

The analysis of environmental samples for low levels of U, Pu, Am and other actinide elements is often hampered by sample-dependent problems involving the composition and/or mineralogy of specific samples. While relatively small samples (1–2 g of soil or 1–2 of water) are required to reach the extremely low detection limits occasionally mandated for environmental monitoring. One approach to avoid the troublesome and often inexplicable problems collectively referred to as matrix effects is to pre-concentrate actinides into a common form that would then behave uniformly and predictably during a subsequent separation scheme. Recently, a new extraction chromatographic resin based on diphosphonate chemistry was developed at Argonne National Laboratory. This resin commercialized as Eichrom's Actinide Resin, exhibits extremely high affinity for actinide elements even in the presence of high concentrations of salts. We have measured the uptake of actinides by the Dipex® extractant from natural waters and natural matrix soil standards. Water samples have been analyzed for gross -activities and gave results that compared favorably to the traditional approach. In addition, we have obtained good recoveries and excellent separations for soil samples as judged by resolution on the -spectra and the complete absence of interfering energies.

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