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Manureshed management seeks to address systemic imbalances in nutrient distributions at scales beyond the farmgate and potentially across county and state boundaries. The U.S. poultry industry, which includes broilers, layers, pullets, and turkeys, has many characteristics that are compatible with achieving a vision of manureshed management, including a history of engaging in local and regional programs to better distribute manure resources. Despite widespread vertical integration that supports large-scale strategic decision making and dry manures that favor off-farm transport, there are still many challenges to poultry manureshed management that require engaging stakeholders other than just the poultry industry. Analysis of county-level nutrient budgets highlights the industry's "mega-manureshed," extending from the Mid-Atlantic, across the southeast, and into northwest Arkansas, Oklahoma, and Texas. The analysis also identifies areas with legacy nutrient build-up that are still present today. Implementing manureshed management in the U.S. poultry industry requires comprehensive consideration of manure treatment technologies, alternative uses such as bioenergy production, market development for treated manure products, transport of manure nutrients from source to sink areas, and manure brokering programs that promote manure nutrient distribution. Fortunately, past and present evolution and innovation within the industry places it as a likely leader of the manureshed vision. This article is protected by copyright. All rights reserved.

New stratigraphic constraints have been detailed for the Amatrice Basin, an intermountain morpho-structural depression of the central Apennines (Italy) hosting up to 60-m-thick Quaternary continental deposits. Through the results coming from a 1:5,000 scale field survey and from facies analyses, we documented the geometry, thickness, and extent of the post-orogenic continental deposits filling this basin. The Quaternary deposits form a complex architecture of purely aggradational and aggradational/degradational terraces with a dominant component of conglomerates and gravels, at the bottom, and subordinate sands, at the top. The Quaternary deposits overlie an up to 1-km-thick succession of flysch sediments that accumulated in the western Laga Basin during the Miocene syn-orogenic phases in central Apennines. The collected data are used to constrain the style and mechanisms of both syn-orogenic (i.e., subsidence and terrigenous sedimentation in foredeep environment) and post-orogenic (i.e., uplift, erosion, and continental sedimentation) phases documented for the central Apennines. In particular, the post-orogenic history of the Amatrice Basin, if compared with those of surrounding intermountain basins of the central Apennines, includes limited basin subsidence, reduced thickness of the post-orogenic covers and progressive deepening of the drainage network during the Quaternary. The results shed light on the source-to-sink history of the Amatrice Basin, which results from a long-lived interaction between regional-scale factors (climate changes, chain uplift, and extensional tectonic regime) that influenced the activity of the hydrodynamic pattern and the amount of intrabasinal sedimentation during the Quaternary.

[Sediment provenance analysis of the sand and silt size fractions of ODP site 861 (46oS, offshore Patagonia) provides insights into erosion and ice drainage of the Patagonian Ice Sheet during the Middle to Late Pleistocene. Focus of erosion during this time period is related to a combined climatic and structural influence on glacial erosion. Temporal variations in sediment provenance contemporaneous with a change in the stratigraphy of this site suggest a re‐organization of ice extent and drainage towards the ocean around 240 kyr ago. These results contribute to constrain ice dynamics of the western side of the Patagonian Ice Sheet during the Pleistocene. , Abstract Pleistocene glaciations have promoted important landscape transformations as a result of high rates of erosion and rapid sediment evacuation to adjacent marine basins. In the Patagonian Andes the role of the Patagonian Ice Sheet on landscape evolution, in particular the spatial patterns of glacial erosion and its influence on sediment fluxes, is poorly documented. Here, we investigate the Middle and Late Pleistocene sedimentary record of the continental slope from Ocean Drilling Program (ODP) Site 861, offshore Patagonia (46°S), to evaluate the link between glaciations, mountain range erosion and continental margin strata formation. Petrographic analysis of the sand‐size fraction (0.063–2 mm) and ɛNd and 87Sr/86Sr measurements in the silt‐size fraction (10–63 µm) indicate that glacial erosion over the last 350,000 years has focused within the Patagonian Batholith, with a minor influence of a proximal source to the drilling site, the Chonos Metamorphic Complex. This shows that erosion has focused in the core of the northern Patagonian Andes, coinciding roughly with the location of the Liquine‐Ofqui Fault Zone and the zone of concentrated precipitation during glaciations, suggesting a combined climatic and structural control on glacial erosion. Temporal variation in the provenance signal is contemporaneous with a marked change in the stratigraphy of ODP Site 861 that occurred after the glaciation of MIS 8 (~240 kyr ago). Before MIS 8, a restricted provenance signal and coarse lithofacies accumulated on the continental slope indicates spatially restricted erosion and efficient transfer of sediment towards the ocean. In contrast, very high provenance variability and finer continental slope lithofacies accumulation after MIS 8 suggest a disorganized expansion of the areas under erosion and a more distal influence of ice sediment discharge to this site. We argue that this change may have been related to a re‐organization of the drainage patterns of the Patagonian Ice Sheet and flow of outlet glaciers to the continental margin during the last two glaciations.]

Moderate soil drying (MD) applied during the mid‐to‐late grain filling stages can promote carbon reserve remobilization in straws (sheaths and stems) and increase the grain weight. The coordination between starch‐to‐sucrose transition in straws and sucrose‐to‐starch conversion in inferior grains is essential for carbon reserve remobilization during grain filling. Herein, to reveal the regulating mechanism of carbon reserve remobilization from source to sink, RNA‐seq was utilized to analyze the dynamic transcript profile in source and sink of rice under MD treatment during grain filling. The expression of amylase genes and amylase activity was enhanced by MD treatment in straws, which is consistent with the increased amylase activity. In inferior grains, it was starch synthesis genes that were upregulated by MD treatment. Furthermore, an elevated ABA was found in both straws and inferior grains, which was caused by an increased expression of NCED1 and downregulation of ABA8OX2 by MD treatment, respectively. Additionally, the expression of MYB30, a transcription factor (TF) that negatively regulates beta‐amylase genes, was reduced in straws by MD, resulting in an increased amylase activity. In contrast, an increased expression of NAC activated the expressions of starch synthesis gene in inferior grains under MD. Therefore, it is MYB30 and NAC that cooperates in source and sink, respectively, to promote carbon reserve remobilization in response to MD. Taken together, genes involved in carbon flow from source to sink are different between rice straws and inferior grains.

In a dynamic network, the quickest path problem asks for a path such that a given amount of flow can be sent from source to sink via this path in minimal time. In practical settings, for example, in evacuation or transportation planning, the problem parameters might not be known exactly a priori. It is therefore of interest to consider robust versions of these problems in which travel times and/or capacities of arcs depend on a certain scenario. In this article, min–max versions of robust quickest path problems are investigated and, depending on their complexity status, exact algorithms or fully polynomial-time approximation schemes are proposed. © 2012 Wiley Periodicals, Inc. NETWORKS, 2012 © 2012 Wiley Periodicals, Inc.

The transport of assimilates from source to sink tissues is mediated by the phloem. Along the vascular system the phloem changes its physiological function from loading phloem to transport and unloading phloem. Sucrose carrier proteins have been identified in the transport phloem, but it is unclear whether the physiological role of these transporters is phloem unloading of sucrose or retrieval of apoplasmic sucrose back into the sieve element/companion cell complex. Here, we describe the dynamic expression of the Ricinus communis sucrose carrier RcSCR1 in the hypocotyl at different sink strengths. Our results indicate that phloem unloading in castor bean is not catalysed by the phloem loader RcSCR1. However, this sucrose carrier represents the molecular basis of the sucrose retrieval mechanism along the transport phloem, which is dynamically adjusted to the sink strength. As a consequence, we assume that other release carrier(s) exist in sink tissues, such as the hypocotyl, in R. communis.

Two types of coupled source/'sink activities are discussed, namely, (i) dislocation exchange between the crystal volume and the boundaries (crystal/boundary exchange, CBE) and (ii) dislocation exchange among branching boundaries (boundary/boundary exchange, BBE). The argumentation is developed over three levels of scale from the bicrystal over the tricrystal to the polycrystal and gives a description of the dislocation transfer in terms of continuous direct, pulsating direct, and alternative dislocation currents. Multifold branching boundaries are understood as multifold coupled wave fields, based on the principle that any dislocation entity being transferred from source to sink is not a continuous entity but a quantum packet consisting of an integer number of unit quantum dislocation, and that therefore any CBE or BBE induced changes of structures, displacement fields, and dislocation densities must be quantized, too. The concept offers manifold access to understanding and manipulation of all those phenomena in polycrystalline matter which involve the dynamics of internal boundaries

Cotton (Gossypium hirsutum L.) yields can vary considerably among years and locations, even under levels of water and nutrients considered adequate. Since photosynthesis is one of the principal components in determining reproductive yield, the objectives of this study were to determine how manipulations of the ratio of photosynthetic source to reproductive sink affect cotton lint yield and yield components (boll mass, seed mass, seed per boll, lint percentage, and bolls per square meter). Field studies were conducted in 1991 and 1992 on a Bosket fine sandy loam with six source-to-sink ratio manipulations (partial fruit pruned, partial leaf pruned, reflectors, open canopy, shaded plots, and an untreated control) imposed on three cotton genotypes: 'DES 119', 'DPL 5690', and 'Prema'. White blooms were tagged twice in both years, and fruit were subsequently harvested after bolls had opened [...]

As technology scales down into the nanometer region new design challenges emerge. Wire delays become the performance bottleneck in VLSI circuits. Copper is introduced as new wiring material because of its low sheet resistivity, hence low signal propagation delay. The main defect mechanism shifts from shorts to opens due to the different manufacturing process for copper wires. Open defects limit functional yield. Parametric yield decreases because of timing uncertainties emerging from manufacturing variation. Clock skew variation becomes critical because it may shorten the cycle length of the critical path. The variation of signal nets has to be considered simultaneously avoiding overly pessimistic designs. Design techniques which reduce the variation of design parameters avoid over design and increase parametric yield. Whereas tree topologies have been applied due to their minimal wire length, the application of generic routing graphs provides multiple paths to specific sinks. Multiple paths from source to sink increase the robustness against open defects and smoothes the effect of variation. New design techniques applying loops in VLSI wiring networks are the topic of this abstract. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

SUMMARY A reciprocal recurrent selection programme was initiated in 1949 to improve the grain-yield performance of Iowa Stiff Stalk Synthetic [BSSS(R)] and Iowa Corn Borer Synthetic no. 1 [BSCB(R)] maize (Zea mays L.) populations. In the same year, a half-sib selection programme was initiated in an open-pollinated maize variety, ‘Alph’ (i.e. BS12), with the same objective. Inbred B14 was the tester variety in the half-sib programme. Previous studies showed that significant grain-yield increases resulted from seven cycles of reciprocal recurrent selection and six cycles of half-sib selection. Growth analysis was used to examine productivity and distribution of dry matter by the unimproved and improved variety hybrids of BSSS(R) × BSCB1 (R)and BS12 × B14A. Only leaf area, leaf-area duration, leaf-area index, and leaf-area index duration were significantly larger in the improved than the unimproved hybrids. These differences occurred mostly during grain filling. Evidently, increased grain yields from recurrent selection in these programmes were consequences of prolonged photosynthetic activity, increased production of photosynthate during grain filling, and increased translocation of photosyntheate from source to sink, in both BSSS(R) × BSCBl(R) and BS12 × B14A.