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For the calculation of the contrast of a defect in semiconducting material, the defect is regarded as a bounded region where the minority carrier lifetime τ' is lower than that (τ) outside the defect region. The minority carrier density in the presence of the defect is normally written in terms of a perturbation series. The conditions for using a perturbation series for different kinds of defects are discussed.

The theoretical description used for the analysis of beam-voltage dependent CL and EBIC contrasts from a surface-parallel dislocation is summarized. The importance of the use of a realistic carrier generation model is discussed and suitable methods of the evaluation of defect parameters (depth position, defect strength) are proposed.

Current interest in integrating livestock with crop production systems warrants further understanding of the impacts of manure application on soil physical processes and properties such as soil's susceptibility to compaction (compactibility) and water retention. We quantified the 71‐yr cumulative impacts of beef (Bos TaurusL.) cattle manure (0 and 27 Mg ha−1yr−1) and inorganic N fertilizer (0, 90, and 180 kg N ha−1yr−1) application to conventionally tilled and irrigated corn (Zea maysL.) on soil compactibility, water retention, available water, and soil organic C (SOC) on a Tripp very fine sandy loam (coarse‐silty, mixed, superactive, mesic Aridic Haplustoll) at the centennial Knorr‐Holden plots of the University of Nebraska's Panhandle Research and Extension Center, Scottsbluff, NE. Manure application improved soil properties at the 0‐ to 30‐cm depth, but inorganic fertilization had no effects. Across N levels, manure application reduced maximum Proctor bulk density by 6% and increased Proctor soil critical water content (water content at which maximum compactibility occurs) by about 17%, indicating that manured soils can be slightly less susceptible to compaction and trafficked at higher water content without being excessively compacted compared with nonmanured soils. Manured plots also retained 18% more soil water at −0.033 MPa and 21% more at −1.5 MPa potential, resulting in about 16% more plant available water compared with nonmanured plots. The SOC concentration increased two‐fold with manure addition and was negatively correlated (r> −0.77) with soil compactibility and positively (r> 0.72) with water retention. Overall, 71‐yr manure application reduced compactibility and increased water retention in this semiarid soil.

Idiopathic pulmonary fibrosis (IPF) is a progressive disease of the middle aged and elderly with a prevalence of one million persons worldwide. The fibrosis spreads from affected alveoli into contiguous alveoli, creating a reticular network that leads to death by asphyxiation. Lung fibroblasts from patients with IPF have phenotypic hallmarks, distinguishing them from their normal counterparts: pathologically activated Akt signaling axis, increased collagen and α-smooth muscle actin expression, distinct gene expression profile, and ability to form fibrotic lesions in model organisms. Despite the centrality of these fibroblasts in disease pathogenesis, their origin remains uncertain. Here, we report the identification of cells in the lungs of patients with IPF with the properties of mesenchymal progenitors. In contrast to progenitors isolated from nonfibrotic lungs, IPF mesenchymal progenitor cells produce daughter cells manifesting the full spectrum of IPF hallmarks, including the ability to form fibrotic lesions in zebrafish embryos and mouse lungs, and a transcriptional profile reflecting these properties. Morphological analysis of IPF lung tissue revealed that mesenchymal progenitor cells and cells with the characteristics of their progeny comprised the fibrotic reticulum. These data establish that the lungs of patients with IPF contain pathological mesenchymal progenitor cells that are cells of origin for fibrosis-mediating fibroblasts. These fibrogenic mesenchymal progenitors and their progeny represent an unexplored target for novel therapies to interdict fibrosis.

A new mass production technology for CIS-absorber formation yielding high-average module efficiencies is introduced. A novel custom-designed oven very successfully exploits the principle of forced convection during heating, CIS formation reaction, and cooling. Cu(In,Ga)(Se,S) 2 absorbers are formed by metal precursor deposition on soda lime glass followed by reaction in selenium/sulfur atmosphere. Processing is performed in a multiple-chamber equipment which handles corrosive, flammable, and toxic process gases from atmospheric pressure to vacuum at high durability. The substrates (size: 50 cm × 120 cm) are processed in batches up to 102 substrates, applying forced convection for very homogenous heat transfer and high heating and cooling rates. Multiple-chamber design and batch size yield high throughput at cycle times above 1 h. This approach combines the specific advantages of batch type and inline processing. An excellent average efficiency of 14.3% with a narrow distribution (+/-0.31%) and a peak efficiency of 15.1% is shown with this technology. Module characteristic distributions during pilot production are presented. Detailed layer analytics is discussed. This straightforward reliable mass production technology is a key for highest module performance and for upscaling. Module efficiencies of 17% can be reached, enabling production costs below 0.38 US$/Wp in a projected GWp plant.

The lowest pods on common bean (Phaseolus vulgaris) are on or near the ground. Yields may improve by raising these pods to reduce yield loss, especially with direct harvest. The objective of this field study was to use gibberellic acid (GA3) to raise lower pods and increase yield. Seeds of cultivars Poncho (Type III, pinto) and Matterhorn (Type II, great northern) were dipped in GA3 at 0, 125, 500, and 2000 ppm and planted in 30-inch rows (2005). Stem elongation was promoted, but emergence and yield were decreased especially for 'Poncho'. In foliar tests in 30-inch rows (2005 and 2006), GA3 was applied to newly expanded unifoliolate leaves. Doses were 0, 0.5, 2, and 8 ppm for 'Poncho' and 0, 31.25, 125, and 500 ppm for 'Matterhorn'. The higher doses raised the low pod by 2 inches, and yields harvested conventionally were increased from 14% to 18%. In 2007, 'Poncho' and 'Matterhorn' unifoliolate leaves were treated with GA3 at 0, 2, and 4 ppm, and 0, 62.5, and 125 ppm, respectively, and then portions of each plot were harvested either manually, conventionally, or directly. Planting was in 22- and 30-inch row spacing. Lower pods were raised by ≈1 inch by GA3. Yields from conventional and direct harvest were increased by foliar GA3 application for both cultivars and both row spacings. Yield from directly harvested GA3-treated plots was comparable to that from untreated conventionally harvested plots. GA3 may play a role in increasing yield from directly harvested common bean in conjunction with genetic and mechanical improvement [ABSTRACT FROM AUTHOR]

Poly(ADP-ribosyl)ation (PARylation) is a post-translational protein modification effected by enzymes belonging to the poly(ADP-ribose) polymerase (PARP) superfamily, mainly by PARP-1. The key acceptors of poly(ADP-ribose) include PARP-1 itself, histones, DNA repair proteins, and transcription factors. Because many of these factors are involved in the regulation of myofibroblast differentiation, we examined the role of PARylation on myofibroblast differentiation. Overexpression of PARP-1 with an expression plasmid activated expression of the α-SMA gene (Acta2), a marker of myofibroblast differentiation in lung fibroblasts. Suppression of PARP-1 activity or gene expression with PARP-1 inhibitors or siRNA, respectively, had the opposite effect on these cells. PARP-1–deficient cells also had reduced α-SMA gene expression. DNA pyrosequencing identified hypermethylated regions of the α-SMA gene in PARP-1–deficient cells, relative to wild-type cells. Interestingly, and of potential relevance to human idiopathic pulmonary fibrosis, PARP activity in lung fibroblasts isolated from idiopathic pulmonary fibrosis patients was significantly higher than that in cells isolated from control subjects. Furthermore, PARP-1–deficient mice exhibited reduced pulmonary fibrosis in response to bleomycin-induced lung injury, relative to wild-type controls. These results suggest that PARylation is important for myofibroblast differentiation and the pathogenesis of pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a progressive and incurable fibroproliferative disorder characterized by unrelenting proliferation of fibroblasts and their deposition of collagen within alveoli, resulting in permanently scarred, nonfunctional airspaces. Normally, polymerized collagen suppresses fibroblast proliferation and serves as a physiological restraint to limit fibroproliferation after tissue injury. The IPF fibroblast, however, is a pathologically altered cell that has acquired the capacity to elude the proliferation-suppressive effects of polymerized collagen. The mechanism for this phenomenon remains incompletely understood. Here, we demonstrate that expression of α2β1integrin, a major collagen receptor, is pathologically low in IPF fibroblasts interacting with polymerized collagen. Low integrin expression in IPF fibroblasts is associated with a failure to induce PP2A phosphatase activity, resulting in abnormally high levels of phosphorylated (inactive) GSK-3β and high levels of active β-catenin in the nucleus. Knockdown of β-catenin in IPF fibroblasts inhibits their ability to proliferate on collagen. Interdiction of α2β1integrin in control fibroblasts reproduces the IPF phenotype and leads to the inability of these cells to activate PP2A, resulting in high levels of phosphorylated GSK-3β and active β-catenin and in enhanced proliferation on collagen. Our findings indicate that the IPF fibroblast phenotype is characterized by low α2β1integrin expression, resulting in a failure of integrin to activate PP2A phosphatase, which permits inappropriate activation of the β-catenin pathway.

AbstractFibroblasts have a central role in the maintenance of tissue homeostasis and repair after injury. Currently, there are no tractable, cost-effective model systems for studying the biology of human fibroblasts in vivo. Here we demonstrate that primary human fibroblasts survive transplantation into zebrafish embryos. Transplanted cells migrate and proliferate, but do not integrate into host tissues. We used this system to study the intrinsic motility of lung fibroblasts from a prototype fibrotic lung disease, idiopathic pulmonary fibrosis (IPF). IPF fibroblasts displayed a significantly higher level of motility than did fibroblasts from nonfibrotic lungs. This is the first in vivoexamination of primary human lung fibroblast motility in health and disease using zebrafish models.

Delta–deepwater fold–thrust belts (DDWFTBs) develop over low-angle detachment faults which link extension to downslope contraction. Detachment faults have been examined in previous studies for the Amazon Fan, Niger, Nile, Angola, Baram and Bight Basin DDWFTBs. The driving mechanisms for the movement along the detachment remain uncertain, however. Previous authors have attributed the movement along detachment faults to high pore-fluid pressure, which reduces the effective normal stress acting on a fault surface thereby encouraging sliding along the fault. However, high pore-fluid pressure has not been directly confirmed in many of these faults due to a lack of well data in detachment surfaces. In this study, finite element modelling was used to test the effects of pore-fluid pressure, coefficient of friction, sediment rigidity and sediment wedge angle on sliding along the detachment. The modelling suggests that increased pore-fluid pressures and decreased coefficients of friction increase slip along a detachment. At hydrostatic pore-fluid pressures, sediment rigidity and sediment wedge angle have relatively little effect on the movement of the sediment wedge along the detachment. Modelling of these conditions using ABAQUS™ improves our understanding of the nature and mechanics of DDWFTBs and their underlying detachments.

Idiopathic pulmonary fibrosis (IPF) is a prevalent, progressive, and incurable fibroproliferative lung disease. The phenotype of IPF fibroblasts is characterized by their ability to elude the proliferation-suppressive properties of polymerized type I collagen. The mechanism underlying this pathological response is incompletely understood but involves aberrant activation of the phosphatidylinositol 3-kinase–Akt signaling pathway owing to inappropriately low phosphatase and tensin homolog phosphatase activity. Akt can phosphorylate and inactivate the forkhead box O3a (FoxO3a) transcriptional factor, which, when transcriptionally active, increases the expression of the CDK inhibitor p27 and promotes cell cycle arrest. Herein, we demonstrate that IPF fibroblasts display high levels of inactive FoxO3a compared with nonfibrotic control fibroblasts because of their high Akt activity. We found that p27 levels are decreased in IPF compared with control fibroblasts cultured on polymerized collagen. Furthermore, overexpression of FoxO3a in IPF fibroblasts increases p27 levels and suppresses the ability of IPF fibroblasts to proliferate on polymerized collagen. In contrast, the expression of dominant-negative FoxO3a augmented control fibroblast proliferation. IHC examination of fibroblastic foci in IPF lung tissue demonstrates the presence of inactive FoxO3a in cells within fibroblastic foci. These data indicate that the ability of IPF fibroblasts to circumvent the proliferation-suppressive properties of polymerized collagen involves inactivation of FoxO3a by high Akt activity, resulting in down-regulation of p27.

The aim of our study was to develop a graphical tool that can be used in addition to standard statistical criteria to support decisions on the number of classes in explorative categorical latent variable modeling for rehabilitation research. Data from two rehabilitation research projects were used. In the first study, a latent profile analysis was carried out in patients with cancer receiving an inpatient rehabilitation program to identify prototypical combinations of treatment elements. In the second study, growth mixture modeling was used to identify latent trajectory classes based on weekly symptom severity measurements during inpatient treatment of patients with mental disorders. A graphical tool, the Class Evolution Tree, was developed, and its central components were described. The Class Evolution Tree can be used in addition to statistical criteria to systematically address the issue of number of classes in explorative categorical latent variable modeling.

This research documented water use, grain yield, and water use efficiency of wheat following a 10‐species cover crop mixture and single‐species plantings (planted no‐till into proso millet residue) compared with winter wheat following a no‐till fallow period. The study was conducted under varying water availability conditions in western Nebraska and northeastern Colorado. Earn 0.5 CEUs in Soil & Water Management by reading this article and taking the quiz at www.certifiedcropadviser.org/certifications/self‐study/775.

Nutrient management recommendations may change as yield levels and efficiency of crop production increase. Recommendations for P, K, and S were evaluated using results from 34 irrigated corn (Zea maysL.) trials conducted in diverse situations across Nebraska. The mean yield was 14.7 Mg ha−1with adequate fertilizer applied. The median harvest index values were 0.52, 0.89, 0.15, and 0.56 for biomass, P, K, and S, respectively. Median grain yields were 372, 49, and 613 kg kg−1of aboveground plant uptake of P, K, and S, respectively. The estimated critical Bray‐1 P level for corn response to 20 kg P ha−1was 20 mg kg−1when the previous crop was corn compared with 10 mg kg−1when corn followed soybean [Glycine max(L.) Merr.]. Soil test K was generally high with only three site‐years <125 mg kg−1. Over all trials, application of 40 kg K ha−1resulted in a 0.2 Mg ha−1mean grain yield decrease. Application of 22 kg S ha−1did not result in significant yield increase in any trial. Soil test results accounted for twice as much variation in nutrient uptake when soil organic matter (SOM) and pH were considered in addition to the soil test nutrient values. The results indicate a need to revise the current recommendation for P, to maintain the current K and S recommendations, and to use SOM and pH in addition to soil test nutrient values in estimating applied nutrient requirements for irrigated high yield corn production.

A series of benzenesulfonyl compounds, 1a-i, containing a BZT moiety was synthesized and characterized, and their antifungal and antibacterial activities were investigated. Compounds 1a and 1d showed the highest activity against Escherichia coli ATCC 25922; in addition 1a presented bactericidal activity against E. coli and Staphylococcus aureus at 8.6 mM. The ability of 1a to generate superoxide anion (O2 .-) was measured and it showed more stimuli in S. aureus compared to sulfathiazole, indicating that 1a can be involved in oxidative stress of bacteria. None of the compounds inhibited the growth of the dermatophytes strains at the tested concentration (250 g/ml).

Glass containing metallic nanoparticles shows unique optical properties and is therefore a promising material for various photonic applications. It is demonstrated, how such material can be structured using external electric fields. The optical properties of such photonic structures are investigated. Prior to the theoretical design of photonic structures in such a glass a critical investigation of the dielectric properties is necessary. A comparison of the effective medium theory and finite element calculations is given. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

CLASPs are widely conserved microtubule plus-end–tracking proteins with essential roles in the local regulation of microtubule dynamics. In yeast, Drosophila, and Xenopus, a single CLASP orthologue is present, which is required for mitotic spindle assembly by regulating microtubule dynamics at the kinetochore. In mammals, however, only CLASP1 has been directly implicated in cell division, despite the existence of a second paralogue, CLASP2, whose mitotic roles remain unknown. Here, we show that CLASP2 localization at kinetochores, centrosomes, and spindle throughout mitosis is remarkably similar to CLASP1, both showing fast microtubule-independent turnover rates. Strikingly, primary fibroblasts from Clasp2 knockout mice show numerous spindle and chromosome segregation defects that can be partially rescued by ectopic expression of Clasp1 or Clasp2. Moreover, chromosome segregation rates during anaphase A and B are slower in Clasp2 knockout cells, which is consistent with a role of CLASP2 in the regulation of kinetochore and spindle function. Noteworthy, cell viability/proliferation and spindle checkpoint function were not impaired in Clasp2 knockout cells, but the fidelity of mitosis was strongly compromised, leading to severe chromosomal instability in adult cells. Together, our data support that the partial redundancy of CLASPs during mitosis acts as a possible mechanism to prevent aneuploidy in mammals.

We apply the concept of epitaxy, which has been proven to be essential for the formation of CuInSe2 and CuGaSe2 out of binary selenide compounds to multinary compounds. We show that the formation of quaternary chalcopyrites is possible starting either with binary or with mixed crystal chalcogenide compounds. The complete sets of chemical solid-state reactions equations are given. The solid-state reactions are expected to proceed faster, if only one sublattice needs to be rearranged. It shows out, that ternary and quaternary chalcopyrite compounds can be synthesised by fast reaction mechanisms directly from chalcogenide compounds. The fastest way to obtain chalcopyrites containing more than four elements is a stepwise process. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In a recent work we have described the importance of epitaxy for the formation of CuInSe2 and CuGaSe2. In this article we identify epitaxial relations between binary selenide compounds serving as educts for the formation of the title compounds. From this we derive a set of possible chemical reaction equations for those solid-state reactions, which will preferably take place. By exploiting these reactions the chalcopyrite compounds can be synthesised smartly in short annealing processes at relatively low temperatures. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In this article we present results of a detailed study of selenization reactions in the quaternary system Cu–In–Al–Se and of the binary subsystem aluminum–selenium. The investigation of solid-state reactions involved in the formation of the compound semiconductor Cu(In,Al)Se2 was performed using real-time X-ray diffraction (XRD) with a time resolution of 22.5 s while annealing an elemental layer stack of the metals covered with selenium. A temperature-resolved phase analysis shows that the formation of the semiconductor takes place via metal-selenides. Ex-situ XRD measurements of the processed thin films show a phase segregation concerning the aluminum content of the formed chalcopyrite. Subsequent Rietveld-refinement of real-time measurements reveals a formation reaction of the quaternary semiconductor Cu(In,Al)Se2 from the γ-In2Se3 related crystal structure of (Al,In)2Se3 and Cu2Se as educts. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Calcium-rich coal combustion fly ash can be used as an amendment to neutralize soil acidity because of its oxides and carbonate content, but its aluminum content could inhibit plant growth if soil pH values fall below optimal agronomic levels. This study measured root and shoot growth of an acid-sensitive barley (Hordeum vulgareL. 'Kearney') grown in the greenhouse on three naturally acid soils. The soils were either untreated or amended with various liming materials (dry fly ash, wet fly ash, and agricultural lime) at application rates of 0,.5, 1, and 1.5 times the recommended lime requirement, then treated with dilute acid solutions to simulate management-induced acidification. Plant growth indexes were measured at 30 days after planting. Root mass per plant and root length per plant were greater for the limed treatments than in the acidified check (0.0 × rate). Root growth in the limed treatments did not differ from root growth in the original nonacidified soils. Top mass per plant in all limed soils was either larger than or not different from that in the original nonacidified soils. Based on top mass per plant, no liming material or application rate was clearly superior. Both fly ash and agricultural lime reduced the impact of subsequent acidification on young barley plants. Detrimental effects of aluminum release on plant growth were not observed. Calcium-rich fly ash at agronomic rates is an acceptable acid-neutralizing material with no apparent negative effects.

A nested polymerase chain reaction (PCR) assay was used to detect early stages of Myxobolus cerebralisin caudal and adipose fin samples from rainbow trout (RT). To determine sensitivity, groups of 10 RT were exposed to 2,000 M. cerebralistriactinomyxons/fish for 1 hour at 15°C and subsequently moved to clean recirculating water. Fish were held for 2 and 6 hours and 1, 2, 3, 5, 7, 10, 30, and 60 days before sampling by nonlethal fin biopsy. Nested PCR performed on fin clips showed that M. cerebralisDNA was detected in caudal fin tissue in 100% of fish up to 5 days postexposure. At days 7 and 10 postexposure, 80% of fish were positive, and at 60 days postexposure, 60% of fish were positive using this technique. Conversely, testing on adipose fin clips proved less sensitive, as positive fish dropped from 80% at day 7 to below 20% at day 10 postinfection. Since detection of M. cerebralisinfection using caudal fin samples coupled with nested PCR is an effective method for detection of early parasite stages, use of this technique provides for accurate, nonlethal testing.

Tillage systems and nutrient management influence soil chemical properties that can impact the long‐term sustainability of dryland production systems. This study was conducted to compare the effects of no‐till (NT) and conventional till (CT) on the soil chemical properties and grain yield of a dryland winter wheat (Triticum aestivumL.)–grain sorghum [Sorghum bicolor(L.) Moench]/corn (Zea maysL.)–fallow rotation. The effects of tillage practice over a 27‐yr period (1962–1989) and the effect of the conversion of CT to NT over a 14‐yr period (1989–2003) on selected soil chemical properties [pH, cation exchange capacity (CEC), base saturation (BS), soil organic C (SOC), K, Ca, Mg, and Bray‐P] at different soil depths was determined. The acidification rate of the NT treatment from 1962 to 2003 was also determined. The study was conducted at North Platte, NE on a Holdrege silt loam (fine‐silty, mixed, mesic Typic Argiustolls). In 1989, there were differences in soil chemical properties between CT and NT at some depths after 27 yr. However, in 2003, 14 yr after converting from CT to NT, there were no differences in the soil chemical properties compared with continuous NT. In 1989 and 2003, the soil chemical properties varied with soil depth. The acidification rate from 1962 to 2003 for the NT treatment in the 0‐ to 15‐cm depth was 1.3 kmol H+ha−1yr−1. This rate of acidification represents 38% of the total potential acidity from N fertilizer applications over 41 yr. Acidification was attributed to nitrification of ammonium‐based fertilizers and leaching of NO3−Long‐term winter wheat (1966–1983) and grain sorghum (1964–1988) grain yields were higher for NT (2718 and 4125 kg ha−1) than CT (2421 and 3062 kg ha−1). Retention of soil moisture as a result of increased residue cover under NT likely contributed to higher NT yields. Soil chemical properties in the wheat–sorghum/corn–fallow rotation will likely continue to change as a result of current management practices. Lime additions may become necessary in the future to ensure the sustainability of crop production in this system.

Knowledge of the solid‐state reactions providing the synthesis of the absorber material Cu(IngGa)Se2well below its melting point is an essential prerequisite for the further optimization of the technologically relevant production processes. Therefore, powder XRD has been applied as nondestructive tool to follow chemical solide‐state reactions in‐situ. Subsequent Rietveld refinement provides the quantitative phase evolution time.

Fly ash produced as a by-product of subbituminous coal combustion can potentially serve as an alternative liming material without negatively affecting corn (Zea maysL.) production in areas where use of conventional liming materials can be uneconomical due to transportation costs. A study was conducted to determine if fly ash produced from the Nebraska Public Power District Gerald Gentleman Power Station located in Sutherland, NE could be used as an alternative liming material. This study had the following objectives 1) compare the effects of fly ash on soil pH with other common agricultural lime materials; 2) determine the effects of fly ash on percent Al saturation in selected soils; and 3) determine the effects of fly ash on corn grain yields. Combinations of dry fly ash (DFA), wet fly ash (WFA), beet lime (by-product of sugar beet Beta vulgarisL. processing) (BL), and agricultural lime (AGL) were applied at rates ranging from 0.43 to 1.62 times the recommended lime rate to plots on four acidic soils (Anselmo fine sandy loam, Hord fine sandy loam, Holdrege sandy loam, and Valentine fine sand). Soil samples were collected to a depth of 0.2 m from plots and analyzed for pH before lime applications and twice periodically after lime application. The Hord and Valentine soils were analyzed for exchangeable Ca, Mg, K, Na, and Al for determination of percent Al saturation on selected treatments and sampling dates. Corn grain yields were determined annually. Depending on the lime source, soil pH increased in the upper 0.2 m of soil the year after application compared with the pre-application soil pH values for some sites and years, whereas in others there were no significant increases in pH. However, all lime materials at each site failed to raise the soil pH in the upper 0.2 m of all the treatments and soil types to the target pH of 6.5. Fly ash and AGL treatments did not significantly increase corn grain yields compared with the control on the Anselmo, Hord, and Holdrege soils. At the Hord site, AGL and DFA significantly reduced percent Al saturation by 3.1% and 3.7% compared with the control 5 years after application, respectively. Fly ash did not negatively affect corn grain yields compared with AGL. Yields were 12,472, 12,233, and 12,177 kg ha−1for the Anselmo, Holdrege, and Hord sites averaged over all treatments and years. The lack of yield response to lime additions was potentially a result of lime materials not raising the soil pH to sufficient levels, higher subsoil pH values, or the exchangeable Al not being high enough prior to lime material application to reduce grain yields in these soils. We conclude that the fly ash utilized in this study and applied at rates in this study, increases soil pH comparable to agricultural lime and is an appropriate alternative liming material.

A major goal in the study of vertebrate mitosis is to identify proteins that create the kinetochore-microtubule attachment site. Attachment sites within the kinetochore outer plate generate microtubule dependent forces for chromosome movement and regulate spindle checkpoint protein assembly at the kinetochore. The Ndc80 complex, comprised of Ndc80 (Hec1), Nuf2, Spc24, and Spc25, is essential for metaphase chromosome alignment and anaphase chromosome segregation. It has also been suggested to have roles in kinetochore microtubule formation, production of kinetochore tension, and the spindle checkpoint. Here we show that Nuf2 and Hec1 localize throughout the outer plate, and not the corona, of the vertebrate kinetochore. They are part of a stable "core" region whose assembly dynamics are distinct from other outer domain spindle checkpoint and motor proteins. Furthermore, Nuf2 and Hec1 are required for formation and/or maintenance of the outer plate structure itself. Fluorescence light microscopy, live cell imaging, and electron microscopy provide quantitative data demonstrating that Nuf2 and Hec1 are essential for normal kinetochore microtubule attachment. Our results indicate that Nuf2 and Hec1 are required for organization of stable microtubule plus-end binding sites in the outer plate that are needed for the sustained poleward forces required for biorientation at kinetochores.

A major goal in the study of vertebrate mitosis is to identify proteins that create the kinetochore-microtubule attachment site. Attachment sites within the kinetochore outer plate generate microtubule dependent forces for chromosome movement and regulate spindle checkpoint protein assembly at the kinetochore. The Ndc80 complex, comprised of Ndc80 (Hec1), Nuf2, Spc24, and Spc25, is essential for metaphase chromosome alignment and anaphase chromosome segregation. It has also been suggested to have roles in kinetochore microtubule formation, production of kinetochore tension, and the spindle checkpoint. Here we show that Nuf2 and Hec1 localize throughout the outer plate, and not the corona, of the vertebrate kinetochore. They are part of a stable “core” region whose assembly dynamics are distinct from other outer domain spindle checkpoint and motor proteins. Furthermore, Nuf2 and Hec1 are required for formation and/or maintenance of the outer plate structure itself. Fluorescence light microscopy, live cell imaging, and electron microscopy provide quantitative data demonstrating that Nuf2 and Hec1 are essential for normal kinetochore microtubule attachment. Our results indicate that Nuf2 and Hec1 are required for organization of stable microtubule plus-end binding sites in the outer plate that are needed for the sustained poleward forces required for biorientation at kinetochores.

The complex behavior of chromosomes during mitosis is accomplished by precise binding and highly regulated polymerization dynamics of kinetochore microtubules. Previous studies have implicated Kin Is, unique kinesins that depolymerize microtubules, in regulating chromosome positioning. We have characterized the immunofluorescence localization of centromere-bound MCAK and found that MCAK localized to inner kinetochores during prophase but was predominantly centromeric by metaphase. Interestingly, MCAK accumulated at leading kinetochores during congression but not during segregation. We tested the consequences of MCAK disruption by injecting a centromere dominant-negative protein into prophase cells. Depletion of centromeric MCAK led to reduced centromere stretch, delayed chromosome congression, alignment defects, and severe missegregation of chromosomes. Rates of chromosome movement were unchanged, suggesting that the primary role of MCAK is not to move chromosomes. Furthermore, we found that disruption of MCAK leads to multiple kinetochore-microtubule attachment defects, including merotelic, syntelic, and combined merotelic-syntelic attachments. These findings reveal an essential role for Kin Is in prevention and/or correction of improper kinetochore-microtubule attachments.

The complex behavior of chromosomes during mitosis is accomplished by precise binding and highly regulated polymerization dynamics of kinetochore microtubules. Previous studies have implicated Kin Is, unique kinesins that depolymerize microtubules, in regulating chromosome positioning. We have characterized the immunofluorescence localization of centromere-bound MCAK and found that MCAK localized to inner kinetochores during prophase but was predominantly centromeric by metaphase. Interestingly, MCAK accumulated at leading kinetochores during congression but not during segregation. We tested the consequences of MCAK disruption by injecting a centromere dominant-negative protein into prophase cells. Depletion of centromeric MCAK led to reduced centromere stretch, delayed chromosome congression, alignment defects, and severe missegregation of chromosomes. Rates of chromosome movement were unchanged, suggesting that the primary role of MCAK is not to move chromosomes. Furthermore, we found that disruption of MCAK leads to multiple kinetochore–microtubule attachment defects, including merotelic, syntelic, and combined merotelic-syntelic attachments. These findings reveal an essential role for Kin Is in prevention and/or correction of improper kinetochore–microtubule attachments.

Group theoretical investigations have a huge potential to simplify calculations in solid state theory. We will discuss the application of group theory to photonic band structures. The symmetry properties of Maxwell's equations will be investigated. We have developed methods to simplify group theoretical investigations based on the computer algebra system Mathematica. The application to photonic band structures will be discussed in detail for two-dimensional photonic crystals.

Coal combustion by-products may offer significant benefits if used properly to neutralize soil acidity, but unintended release of trace components must be considered. A study was conducted with two objectives (i) To compare the efficacy of two different preparations of fly ash with that of conventional ag lime for their ability to raise soil pH and reduce exchangeable Al; and (ii) to determine if the Al applied in fly ash produces detrimental changes in soil properties following subsequent acidification. Either fly ash in one of two forms, or conventional ag lime, was applied to three acid soils (Anselmo loam, Valentine sandy loam, and Holdrege sandy loam) in a pot study at rates equal to 0.5, 1.0, and 1.5 times the soils’ lime requirements. Soils were equilibrated in triplicate at approximately 33 kPa water potential in the greenhouse for 315 days (liming phase), during which pH and exchangeable aluminum (Al) were measured. The soils were then acidified under similar conditions for 439 days (acidification phase) by adding dilute acid solution to simulate management-induced acidification, and pH and exchangeable Al were then measured again. Both fly ashes and ag lime were effective in raising soil pH by up to 1.2 units and in reducing exchangeable Al by up to 5.6 mg kg−1. Two-way interactions involving soil, liming material, and rate of application produced different results for combinations of these factors. All amendments helped the soils resist subsequent acidification compared with zero-rate treatments but differed based on the 3-way combinations of soil, liming material, and rate of application. We concluded that overliming (as indicated by exceeding the target pH of 6.5) is a problem with all liming materials on the coarsest soils, suggesting that lime calibration should be re-examined. The fly ash materials seem to contribute to soil exchangeable Al after acidification, but this contribution is inconsequential if soil pH values are maintained at agronomic optima.

Site‐specific N management (SSNM) has been suggested as one means of further increasing the efficiency with which N fertilizers are used and reducing environmental impact. Field studies to evaluate the potential for SSNM to reduce NO3‐N leaching from irrigated maize (Zea maysL.) were conducted from 1994 to 1997. Uniform management (UM) was compared with a SSNM strategy (variable rate technology, VRT) based on an existing N recommendation algorithm for maize using grid sampled soil organic matter and root zone soil residual NO3‐N. A third treatment (reduced variable rate technology, RVRT) evaluated the potential for a reduced rate of N to adequately supply crop N demand when combined with variable rate application. Averaged across all site‐years, there was no significant difference in the total amount of N applied, 142 kg N ha−1with UM, 141 kg N ha−1with VRT. Treatment mean grain yields ranged from 4.5 to 13.9 Mg ha−1and were influenced relatively little by treatment, with VRT yield significantly reduced compared with UM in two site‐years, and UM yield significantly reduced compared with VRT in one site‐year. Treatment mean soil residual NO3‐N in the 0.9‐m root zone ranged from 2.7 to 14.0 mg kg−1, and was low (<6 mg kg−1) for eight site‐years, with no effect of treatment on NO3‐N concentration. For the five site‐years with elevated NO3‐N concentrations (>6 mg kg−1), there were no significant differences between UM and VRT treatments, while RVRT treatment reduced residual NO3‐N for three site‐years. We conclude that the spatial application of the existing recommendation algorithm developed for uniform application may be inappropriate, at least for these sites, and that unique recommendation equations for major soils and climatic regions may be necessary to achieve substantial increases in N‐use efficiency. This study also suggests that improved recommendation algorithms may often need to be combined with methods (such as remote sensing) to detect crop N status at early, critical growth stages followed by carefully timed, spatially adjusted supplemental fertilization to achieve optimum N‐use efficiency.

Elimination of ''Undesired Components'' by Automated AutotransfusionBackground: Usefulness and efficacy of automated autotransfusion in the process of recovering autologous, washed erythrocytes are well documented. The primary advantage compared to direct autotransfusion systems results from a more or less effective elimination of undesired components of wound and drainage blood. Material and Methods: The autotransfusion device Sequestra 1000( (Medtronic) was investigated. Assessed were haemoglobin (Hb), haematocrit (Hct), thrombocytes (PLT), free Hb (f-Hb), β-thromboglobulin (β-TG), elastase, lactate dehydrogenase (LDH), thrombin-antithrombin-III complex (TAT), plasmin-antiplasmin complex (PAP), fibrin degradation products (FDP) and the complement C3 in wound blood as well as in the autologous erythrocyte concentrate. Results: The wound blood showed, in comparison to normal as well as, low levels of Hb (6.2 mmol/l), Hct (0.28) and PLT (91 G/l), whereas indicators of cell decomposition (f-Hb:778 µmol/l, β-TG: >429 IU/ml and LDH: 98 µmol/l s–1) were increased. There was an increased concentration of Hb in the washed autologous erythrocyte concentrate, and undesired components were decreased. Conclusion: With automated autotransfusion, the plasmatic factors can be separated and removed. The quality of an automated system is demonstrated by the elimination rates of the purification process. The elimination rates showed a removal of undesired wound blood components greater than 80%.

The present contribution introduces theoretical studies of photonic crystals. On the basis of Maxwell's equations and a ‘plane wave expansion’ band structures and densities of states are computed for triangular and square 2D lattices of air columns in silicon. The main topic of the paper are investigations of band gap modifications (TM- and TE-polarization) for pores of deteriorating roundness, approximated by ellipses of varying eccentricity. The presented computations include the consideration of background structures in the form of stripes (SiO2) in the model. The results are compared with calculations for circular air columns of varying filling factors.

Although the importance of the addition of Zn to a fertilizer program for corn (Zea maysL.) production has been recognized for some time, the question of effectiveness of source and rate has not been completely resolved. This is especially true for situations where Zn is applied in fluid fertilizers. The objective of this study was to evaluate the effect of five Zn sources [ZnEDTA, Zn‐NH3complex, ZnO, ZnSO4, and Zn(NO)3)2] applied at five rates (0, 0.11, 0.33, 1.12, and 3.36 kg Zn ha−1) on the growth and yield of irrigated corn on sandy soils. The experiments were conducted at four locations during a 2‐yr period. All Zn sources were suspended in ammonium polyphosphate and applied to the side of and below the seed at planting. Whole corn plants were collected at two growth stages and analyzed for Zn. Significant differences among Zn sources for Zn uptake were shown. ZnEDTA performed poorly at two sites due to early season leaching; however, it was the superior source at a calcareous site. The Zn‐NH3complex was the superior source at one of the sites. The 0.1MHCl and DTPA soil tests correlated well with early Zn uptake for the noncalcareous sites. The critical DTPA soil test level for grain response at these locations was near 0.4 mg kg−1. Grain yields were increased by Zn fertilization at only two locations and there were no differences among Zn sources or significant Zn rate by source interactions. Regression equations for the responsive sites showed that between 1 and 2 kg Zn ha−1was required to attain maximum yield. Although Zn uptake indicated differences in performance of Zn sources, the differences were not reflected in grain yield.

AbstractThe life history, behaviour, and mortality of the western ash bark beetle, Hylesinus californicus(Swaine), was investigated in green ash, Fraxinus pennsylvanicusvar. subintergerrima(Vahl) Fern., in Calgary, Alberta. This species is univoltine with an apparent obligate diapause in the adult (overwintering) stage. Adults emerge from overwintering sites in the bases of ash boles from mid-April to mid-May and fly or walk up the bole to the crown where maturation feeding, mating, and reproduction occur. Eggs are present by late April, larvae by early May, pupae by mid-July, and new adults by late July. There are three larval instars. Beetles emerge from larval galleries in August and enter fresh phloem in uninfested parts of branches to feed for up to 6 weeks. Beetles leave feeding galleries from mid-September to early November and migrate by walking, falling, and flying to overwintering sites in the base of ash boles. Total mortality from egg to eclosed brood adult was 80.6%. Disease, parasitoids, and dehydration were the main causes of mortality. Eight hymenopterous parasitoid species were identified; the pteromalid wasp Rhaphitelus maculatusWalker was the most abundant. Tree hazard rating, maintenance of tree health, removal of susceptible and infested host material, and application of pesticides are suggested for management of western ash bark beetle populations.