The Changing Financial Structure of the U.S. Farm Sector

Agricultural Finance,

Root Rating : Corn Yield Interactions

The northern corn rootworm, Diabrotica 1ongicornis barberi Smith and Lawrence (NCR) and the western corn rootworm D. vtrgifera virgtfera·LeConte (WCR) are the two species of rootworms of economic importance in South Dakota corn fields. NCRs infest both first year corn fields and continuous corn whereas WCRs generally infest continuous corn fields. Damage can occur from larval feeding on roots which inhibits nutrient and. moisture uptake, increases propensity for lodging or by adult feeding on silks which causes losses in pollination and seed set. Adult emergence begins in early July and continues until early September. Female rootworm adults mate and then lay eggs in cracks in the soil. Rootworms overwinter as eggs in the soil with egg hatch occurring in June and continuing until early July. The larval stage of the rootworm feeds on corn roots until pupation occurs in August. One generation of rootworms per year occurs in South Dakota. Control of rootworms is attempted through application of granular insecticides at planting and crop rotation. Yield increases from the use of insecticides was first shown by Cox and Lilly. Resistance to insecticides was first noted in Nebraska and recorded by Ball and Weekman. Crop rotation is the first recommendation by extension entomologists in the North Central Region. Root ratings developed in 1971 by Hills and Peters are the standard for checking insecticide efficacy. Using this rating system and pooled agronomic and edaphic factors, Turpin et al, determined a rating of 2.5 as the economic injury level. No investigations have been published that correlate root ratings to yields on an individual plant or field basis. With this in mind, the objectives of my research were three fold. The first objective was to assess corn root damage by Diabrotica larvae and their relationship to corn yield losses; secondly, to determine if correlations exist between corn root damage ratings and yields; and third to potentially serve as an insight for establishing a method of damage rating that will provide a positive correlation between root ratings and yields on a field basis

Magnetostratigraphy of Oligocene to Pleistocene Sediments, Sites 558 and 563

Integrated magnetostratigraphic and biostratigraphic studies of DSDP Sites 563 and 558 (western North Atlantic) show that, except for a short (~2 Ma) early Miocene hiatus, deposition was continuous from time of seafloor formation (Site 563, between Anomalies 12 and 13; Site 558, between Anomalies 13 and 15) through the Miocene at both sites. Several biostratigraphic datum levels, which have been correlated firmly with magnetic polarity chrons elsewhere, allow correlation of the magnetostratigraphy with the geomagnetic polarity time scale. Based upon that calibration, sediment accumulation rates were low to moderate ( 10 m/ Ma) in the middle-late Miocene after a short hiatus (Chron C5E is missing at both sites). The established magnetochronology is used to make direct magnetobiostratigraphic correlations. For the Oligocenelower Miocene samples, these correlations agree well with previously published first-order correlations. However, our correlations differ from the earlier indirect middle to upper Miocene correlations. In particular, indirect methods were previously used to correlate magnetostratigraphic Chron 11 ( = Zone NN9) with marine Anomaly 5A (Chron C5AN). However, Zone NN9 ( = Chron 11) and associated Zone N16 occur in a long normal interval at Sites 563 and 558 that best correlates with marine magnetic Anomaly 5. This reassignment (Chron 11 = Anomaly 5 = Chron C5N) requires an approximately 1.5 2 Ma upward shift in nannofossil zonal boundaries NN7/NN8 through NN10/NN11. The stratotype lower upper Miocene (Tortonian) is biostratigraphically linked with Zones NN9-NN11. Because Zone NN9 occurs in magnetic Anomaly 5 correlative (Chron C5N), the middle-upper Miocene boundary (basal Tortonian) is probably near the base of Chron C5N, with an estimated magnetochronologic age of 10.4 Ma

Technical Comments: Sea Level History

Bilal U. Haq and his co-workers have completed an important update of the chronology of coastal onlap and eustatic fluctuations in Mesowic and Cenowic time. Seismic stratigraphic results are augmented in the new charts by outcrop and well-log studies to document an impressive total of 119 sea level cycles since the beginning of the Triassic. In addition, the Cretaceous results have been published officially for the first time. However, apart from distinguishing between relative changes of coastal onlap and eustasy, the methodology and assumptions are much the same as those used to construct the first version of the "sea level curve" in 1977. In a recent evaluation of the seismic stratigraphic record of sea level change, we drew attention to two problems in particular. 1) All of the observed depositional cycles are assumed by Haq et al. to be eustatic. 2) The global onlap chart, which forms the basis for the smoothed eustatic curve, has little physical meaning

Catalyst for carbon monoxide oxidation

A catalyst is disclosed for the combination of CO and O2 to form CO2, which includes a platinum group metal (e.g., platinum); a reducable metal oxide having multiple valence states (e.g., SnO2); and a compound which can bind water to its structure (e.g., silica gel). This catalyst is ideally suited for application to high-powered pulsed, CO2 lasers operating in a sealed or closed-cycle condition

The small GTPase Rab2 functions in the removal of apoptotic cells in Caenorhabditis elegans

We identify here a novel class of loss-of-function alleles of uncoordinated locomotion(unc)-108, which encodes the Caenorhabditis elegans homologue of the mammalian small guanosine triphosphatase Rab2. Like the previously isolated dominant-negative mutants, unc-108 loss-of-function mutant animals are defective in locomotion. In addition, they display unique defects in the removal of apoptotic cells, revealing a previously uncharacterized function for Rab2. unc-108 acts in neurons and engulfing cells to control locomotion and cell corpse removal, respectively, indicating that unc-108 has distinct functions in different cell types. Using time-lapse microscopy, we find that unc-108 promotes the degradation of engulfed cell corpses. It is required for the efficient recruitment and fusion of lysosomes to phagosomes and the acidification of the phagosomal lumen. In engulfing cells, UNC-108 is enriched on the surface of phagosomes. We propose that UNC-108 acts on phagosomal surfaces to promote phagosome maturation and suggest that mammalian Rab2 may have a similar function in the degradation of apoptotic cells

Evaluating the Stratigraphic Response to Eustasy from Oligocene Strata in New Jersey

Previously published Oligocene eustatic records are compared with observed stratigraphic architecture at the New Jersey continental margin in order to evaluate the stratigraphic response to eustatic change. Lower to mid-Oligocene sequence boundaries (33.8–28.0 Ma) are associated with relatively long hiatuses (0.3–0.6 m.y.), in which sedimentation in many places terminated during eustatic falls and resumed early during eustatic rises. Upper Oligocene sequence boundaries are associated with relatively short hiatuses (less than 0.3 m.y.), and provide the best constraints on phase relations between sea-level forcing and margin response. The interval represented by each upper Oligocene sequence varies in dip profile. At updip locations, landward of the clinoform rollover in the underlying sequence boundary, sedimentation commenced after the eustatic low and terminated before the eustatic high (with partial erosion of any younger record). At downdip locations, sedimentation within each sequence was progressively delayed in a seaward direction, beginning during the eustatic rise and terminating near the eustatic low. Combining data from all available boreholes, ages of sequence boundaries (correlative surfaces) correspond closely with the timing of eustatic lows, and ages of condensed sections (intervals of sediment starvation) correspond with eustatic highs

Reconstruction of Tertiary Progradation and Clinoform Development on the New Jersey Passive Margin by 2-D Backstripping

We have reconstructed the Oligocene to Middle Miocene paleobathymetry and stratigraphy of the New Jersey margin using a modified backstripping technique. By analyzing the geometry of the margin through time, we investigate its response to fluctuating sea level, changing climate, and variable sediment supply during the Tertiary. The reconstructions reveal a change in the margin morphology from a more steeply dipping (1 : 300 to 1 : 500) carbonate ramp in the Eocene to a flatter shelf with a sharp shelf edge at present. This was accomplished by an increase in the terrigenous sediment supply that filled available accommodation and caused progradation across the margin. We link the increase in sediment flux with climatic cooling rather than tectonic processes. The progradation is evidenced by a series of clinoforms whose formation was modulated by sea level and which extend over 100 km across the shelf. The height and dip of the clinoforms increased as they extended onto the deeper parts of the earlier ramp. The Miocene clinoform rollovers at the New Jersey margin had water depths of ∼60–130 m and are interpreted as the edge of a new continental shelf built over the older ramp. Sea-level fall was probably insufficient to drive the Miocene shorelines past the shelf breaks. Thus, measurements of sea-level amplitude based upon `coastal' onlap over the clinoforms are not reliable

Miocene stable isotopic stratigraphy and magnetostratigraphy of Buff Bay, Jamaica

Previously reported biostratigraphic relationships from middle-upper Miocene sections exposed near Buff Bay, Jamaica (18°N, tropical bioprovince), differ from the subtropical North Atlantic (Sites 563 and 558). Time scales for this interval rely on correlations established at these subtropical sites, and the differences with the tropical section have implications to global correlations. Planktonic foraminiferal Zones N13 and N15 are thick at Buff Bay but are virtually absent at Sites 563 and 558; nannofossil Zone NN9 is associated with Zone N15 and uppermost Zone N14 at Buff Bay but is associated with Zone N16 at the other sites. Magnetostratigraphic data presented here further complicate the interpretation: Zone NN9 is associated with a thick normal magnetozone at Sites 563 and 558; at Buff Bay, it is associated with a thick reversed magnetozone. Although a secondary magnetization at Buff Bay makes it difficult to identify confidently Miocene normal magnetozones, the thick reversed magnetozone most likely represents the paleomagnetic field and correlates with Chron C5r. The magnetobiostratigraphic relationships require either diachrony of taxa or two mutually exclusive hiatuses in Jamaica and the North Atlantic. We address this problem by analyzing benthic foraminiferal δ^18O and δ^13C from the Buff Bay section. These isotopic data allow us to evaluate three hypotheses that reconcile the magneto-, bio-, and isotopic stratigraphic data and conclude that the first and last occurrences of five taxa were diachronous by ~0.3-0.5 m.y. between tropical and subtropical locations. This requires revised age estimates for late middle to early late Miocene biostratigraphic datum levels. We suggest that the ranges of several taxa are useful for endemic tropical or subtropical zonations, but correlations between the low and midlatitudes were affected by an increase in latitudinal thermal gradients during the late middle Miocene. However, we admit that further studies are needed before this issue is resolved

Vasculitis of the gastrointestinal tract in chronic periaortitis

The term "chronic periaortitis" (CP), proposed by Mitchinson in 1984, comprises 3 main entities: idiopathic retroperitoneal fibrosis (IRF), inflammatory abdominal aortic aneurysms (IAAAs), and perianeurysmal retroperitoneal fibrosis (PRF).The presence of constitutional symptoms, high acute-phase reactants, positive autoantibodies, and associated autoimmune diseases suggests a systemic inflammatory process. Histopathologic findings show vasculitis with fibrinoid necrosis involving the aortic vasa vasorum as well as the small and medium retroperitoneal vessels.We reviewed the medical records of 608 patients with a diagnosis of vasculitis involving the gastrointestinal (GI) tract at the Mayo Clinic between January 1996 and December 2007. Only patients with biopsy-proven or typical angiographic findings of vasculitis localized to the GI tract were included.Five patients were identified with evidence of CP (1 patient with PRF, 1 with IRF, and 3 with IAAAs). Three patients were men, and the median age at diagnosis was 49 years. The diagnosis of GI vasculitis and CP was made simultaneously in 4 patients. At the time of onset, all patients had abdominal pain and constitutional manifestations; the median erythrocyte sedimentation rate was 62.5 mm/1 h (range, 20-86 mm/1 h). All patients had evidence of mesenteric vasculitis at angiography. Three patients also had associated renal artery stenoses. Abdominal computed tomography showed spleen infarcts in 2 patients, bowel wall thickening in 1, and liver infarction in 1. Two patients underwent surgical intervention for acute abdomen; there was histologic evidence of small bowel infarcts and infarction of the spleen and liver in 1. Oral prednisone was administered to all 5 patients (median starting dose, 60 mg/d; range, 25-80 mg/d). Three patients also received immunosuppressive agents, 1 tamoxifen, and 1 anti-tumor necrosis factor therapy. All patients had at least 1 relapse or recurrence of vasculitis, but at last visit, GI vasculitis and CP were in remission in all 5 patients.This study provides evidence that GI manifestations due to mesenteric vasculitis may be associated with CP. Vasculitic involvement of the renal arteries is also frequently present in these patients. Aggressive immunosuppressive treatment should be promptly initiated to forestall abdominal complications. These findings reinforce the hypothesis that a vasculitic process plays an important role in the pathogenesis of CP