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HighlightsPhosphoric acid (PA) increased water-soluble phosphorus (WSP) from 0.31 to 47.4 g P kg-1 in poultry litter ash (PLA).Ideal granule size was identified at 29% acidulation (14.5 g acid to 50 g PLA) with granules averaging 3.14 mm.Bulk fertilizer production needed 32% PA addition, and adequate mixing equipment is important for PA efficiency.Granule size and strength were adequate as compared to industry standards and commercial fertilizers.Abstract. Manure-to-energy systems effectively recycle poultry litter (PL) into poultry litter ash (PLA) that densifies and concentrates the phosphorus (P) content by a factor of 4 to 10. However, high conversion temperatures reduce nutrient solubility and produce small particulate materials. To redistribute manure nutrients beyond the original production location by improving the physical and chemical characteristics of PLA, the objectives of this research were to: (1) determine the phosphoric acid (H3PO4) acidifying effect on water-soluble P (WSP), measurable total P (TP), granulation point, and granule size and (2) conduct large-scale granulated poultry litter ash bulk (GPLA-B) granulation to determine the larger-scale formulations and granule physical characteristics produced. We measured bulk density, force and friction resistance, and granule size as compared to industry-standard triple superphosphate (TSP). Acidulation experiments were arranged in a completely randomized design with four replications per H3PO4 acidulation percentage. Increasing acidulation percentages from 0% to 50% H3PO4 (laboratory-grade white phosphoric acid) increased measurable TP from 50.63 to 116.90 g kg-1 and WSP from 0.31 to 47.4 g P kg-1 (LSD0.05 10.13 and 2.65 g P kg-1, respectively). Acidulation dose response relationships created simple linear regression equations to predict changes in measurable TP and WSP, pH, and exothermic reaction temperature, which all increased with acidulation. The loose (1.01 g cm-3) and packed (1.03 g cm3) bulk densities of GPLA-B were significantly less than those of TSP (1.14 and 1.30 g cm3, respectively) (LSD0.05 = 0.03 and 0.02 g cm-3). Compared to TSP particles (2.86 mm), GPLA particles (3.73 mm) were significantly larger (LSD0.05 = 0.61 mm); however, the force resistance of GPLA (4.53 kgf) was significantly less than that of TSP (5.95 kgf) (LSD0.05 = 0.61 kgf). Results showed that the physical characteristics of GPLA met industry standards and validated the adaptability of GPLA as an alternative P source. Furthermore, GPLA has higher elemental analysis, greater solubility, and improved form, which addresses the undesirable characteristics of ungranulated PLA and supports the use of GPLA for fertilizer and nutrient distribution. Keywords: Acidulation, Fertilizer, Granulation, Phosphorus, Poultry litter ash.

Low tunnels (LTs) enhance vegetative growth and production in comparison with open field, but it is not known whether nitrogen (N) requirements and use efficiency increase or decrease for optimal crop performance. Therefore, the purpose of this study was to determine differences in N requirement, uptake, and use efficiency in basil grown under LTs compared with open field. The experimental design each year was a split plot with four replications. The main effect (plots) was N fertilizer application rate (0, 37, 74, 111, 148, and 185 kg.ha(-1)) and the secondary effect (subplots) was production system (LTs covered with spun-bonded rowcover vs. open field). Plant height and stem diameter were greater under LT than open field; however, they were unaffected by N fertilizer rate. Total fresh and dry weight increased with LT by 61% and 58% and by 50% and 48% in 2017 and 2018, respectively. Optimum N rates for fresh weight (98% of peak yield) were 124 and 104 kg.ha(-1) N under LT and open field, respectively. Leaf N concentration decreased under LT, but total plant N uptake increased because of increased dry weight. Without fertilization, soil available N use efficiency (SNUE) for dry weight increased by 45% and 66% in 2017 and 2018, respectively. Mixed results were obtained for N fertilizer use efficiency (NFUE) in response to N rate. In conclusion, LT increased summer production of sweet basil, total plant N uptake, and SNUE. National Institute of Food and Agriculture, U.S. Department of Agriculture (USDA) through the Southern Sustainable Agriculture Research and Education (SARE) program [2015-38640-23780, LS16-268] This project is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture (USDA), under award number 2015-38640-23780 through the Southern Sustainable Agriculture Research and Education (SARE) program under subaward number LS16-268. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the USDA or SARE. USDA is an equal opportunity employer and service provider.

Soybean (Glycine max) commonly experience Mn deficiencies in the coarse-textured soils of Coastal Plain Virginia, especially under high pH conditions. The objective of this study was to investigate...

Environmental and economic goals encourage the use of soil N tests to improve fertilizer N (FN) management in corn (Zea mays L.). Recently, the Solvita 1-d CO₂ burst test, which proposes to estimate soil potentially mineralizable N (PMN), has been promoted as a tool for FN recommendations. We aimed to compare the Solvita test with the established presidedress nitrate test (PSNT) for estimating optimum sidedressed FN rates in a typical corn crop rotation in the Mid-Atlantic United States that includes winter annual cover crops (WCCs). Research was conducted at eight locations from 2012 to 2014. Three WCC treatments [cereal rye (Secale cereale L.), hairy vetch (Vicia villosa Roth ssp. villosa) or a cereal rye–hairy vetch mix] were the main plots and 10 FN rates were the subplots. The WCCs affected preplanting (PP) Solvita results at one location, V4 NO₃–N at 0 to 15 cm (PSNT15) at four locations, and V4 NO₃–N at 0 to 30 cm (PSNT30) at two locations. Correlations between soil N test parameters and relative corn yields ranged from 0.31 to 0.13. Values for PSNT15 and PSNT30 correlated positively with corn check yields (r = 0.41 and 0.39 respectively). Solvita did not provide additional information to PSNT for predicting preplanting PMN, V4 PMN, or corn check yields. The advantages of the Solvita test were its simplicity, speed of analysis, and lower coefficient of variation relative to the PSNT. Neither method was consistently effective for predicting WCC effects on soil N or relative corn yield.

Optimal N application is critical to ensure profitable soft red winter wheat (Triticum aestivum L.) production and limit negative environmental effects. This study was conducted using 12 wheat lines grown in two Ohio and six Virginia environments to determine the effects of differentially split N rates on grain yield, yield components, and N-related traits. Upon analysis of wheat lines in two contrasting photoperiod groups, it was discovered that wheat lines containing the photoperiod sensitivity allele (Ppd-D1b) conferred a significant (P < 0.05) yield advantage under N-limited conditions in Ohio and across N treatments in half of the Virginia testing environments. This resulted from increased harvest index, grains per square meter, number of kernels per spike, and floret fertility in Ppd-D1b lines relative to lines with the insensitive allele (Ppd-D1a). However, wheat genotypes in the photoperiod-insensitive allelic group had significantly higher (P < 0.05) grain N concentration in all Virginia testing sites. A spring split N application of 33 kg N ha⁻¹ at Zadoks growth stage (GS) 25 and 101 kg N ha⁻¹ at Zadoks GS 30 produced the highest grain yields and grain N contents in five of the six Virginia environments. Nitrogen utilization efficiency was the primary contributor to variation in N use efficiency under higher N rates, whereas N uptake efficiency was the greatest contributor under low N rates. The contribution of N utilization and uptake efficiencies varied among wheat lines in the Ppd-D1a group when 67 kg N ha⁻¹ was applied at Zadoks GS 25 under the moderate and standard N rates.

While the phenomenon of excess vehicle emissions from cold-start conditions is well known, the magnitude and duration of this phenomenon is often unclear due to the complex chemical processes involved and uncertainty in the literature on this subject. This paper synthesizes key findings regarding the influence of ambient and engine temperatures on light-duty vehicle (LDV) emissions. Existing literature, as well as analytical tools like the U.S. Environmental Protection Agency’s Motor Vehicle Emission Simulator (MOVES), indicate that while total vehicle emissions have dropped significantly in recent years, those associated with cold starts can still constitute up to 80% for some pollutant species. Starting emissions are consistently found to make up a high proportion of total transportation-related methane (CH4), nitrous oxide (N2O), and volatile organic compounds (VOCs). After 3–4 min of vehicle operation, both the engine coolant and the catalytic converter have generally warmed, and emissions are significantly lower. This effect lasts roughly 45 min after the engine is shut off, though the cooling rate depends greatly on the emission species and ambient temperature. Electrically (pre-)heated catalysts, using the bigger batteries available on hybrid drivetrains and plug-in vehicles, may be the most cost-effective technology to bring down a sizable share of mobile source emissions. Trip chaining (to keep engines warm) and shifting to non-motorized modes for shorter trips, where the cold start can dominate emissions, are also valuable tactics.

Ammonia (NH) emissions from animal manures can cause air and water quality problems. Poultry litter treatment (PLT, sodium bisulfate; Jones-Hamilton Co.) is an acidic amendment that is applied to litter in poultry houses to decrease NH emissions, but currently it can only be applied once before birds are placed in the houses. This project analyzed the effect of multiple PLT applications on litter properties and NH release. Volatility chambers were used to compare multiple, single, and no application of PLT to poultry litter, all with and without fresh manure applications. A field component consisted of two commercial broiler houses: one had a single, preflock PLT application, while the other received PLT reapplications during the flock using an overhead application system. In the volatility chambers, single and reapplied PLT caused greater litter moisture and lower litter pH and , relative to no PLT. After 14 d, NH released from litter treated with reapplied PLT was significantly less than litter with both single and no applications. Furthermore, total N in litter was greatest in litter treated with reapplied PLT, increasing its fertilizer value. In the commercial poultry houses, PLT reapplication led to a temporary decrease in litter pH and , but these effects did not last because of continued bird excretion. Although one preflock PLT application is currently used as a successful strategy to control NH during early flock growth, repeat PLT application using the overhead reapplication system was not successful because of problems with the reapplication system and litter moisture concerns.

Leaching of nutrients through agricultural soils is a priority water quality concern on the Atlantic Coastal Plain. This study evaluated the effect of tillage and urea application on leaching of phosphorus (P) and nitrogen (N) from soils of the Delmarva Peninsula that had previously been under no-till management. Intact soil columns (30 cm wide × 50 cm deep) were irrigated for 6 wk to establish a baseline of leaching response. After 2 wk of drying, a subset of soil columns was subjected to simulated tillage (0–20 cm) in an attempt to curtail leaching of surface nutrients, especially P. Urea (145 kg N ha -1 ) was then broadcast on all soils (tilled and untilled), and the columns were irrigated for another 8 wk. Comparison of leachate recoveries representing rapid and slow flows confirmed the potential to manipulate flow fractions with tillage, albeit with mixed results across soils. Leachate trends in the finer-textured soil suggest that tillage impeded macropore flow and forced greater matrix flow. Despite significant vertical stratification of soil P that suggested tillage could prevent leaching of P via macropores from the surface to the subsoil, tillage had no significant impact on P leaching losses. Relatively high levels of soil P below 20 cm may have served as the source of P enrichment in leachate waters. However, tillage did lower losses of applied urea in leachate from two of the three soils, partially confirming the study’s premise that tillage would destroy macropore pathways transmitting surface constituents to the subsoil.

© 2017 American Chemical Society. Replacing passive ion-exchange membranes, like Nafion, with membranes that use light to drive ion transport would allow membranes in photoelectrochemical technologies to serve in an active role. Toward this, we modified perfluorosulfonic acid ionomer membranes with organic pyrenol-based photoacid dyes to sensitize the membranes to visible light and initiate proton transport. Covalent modification of the membranes was achieved by reacting Nafion sulfonyl fluoride poly(perfluorosulfonyl fluoride) membranes with the photoacid 8-hydroxypyrene-1,3,6-tris(2-aminoethylsulfonamide). The modified membranes were strongly colored and maintained a high selectivity for cations over anions. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and ion-exchange measurements together provided strong evidence of covalent bond formation between the photoacids and the polymer membranes. Visible-light illumination of the photoacid-modified membranes resulted in a maximum power-producing ionic photoresponse of ∼100 μA/cm2and ∼1 mV under 40 Suns equivalent excitation with 405 nm light. In comparison, membranes that did not contain photoacids and instead contained ionically associated RuII-polypyridyl coordination compound dyes, which are not photoacids, exhibited little-to-no photoeffects (∼1 μA/cm2). These disparate photocurrents, yet similar yields for nonradiative excited-state decay from the photoacids and the RuIIdyes, suggest temperature gradients were not likely the cause of the observed photovoltaic action from photoacid-modified membranes. Moreover, spectral response measurements supported that light absorption by the covalently bound photoacids was required in order to observe photoeffects. These results represent the first demonstration of photovoltaic action from an ion-exchange membrane and offer promise for supplementing the power demands of electrochemical processes with renewable sunlight-driven ion transport.

Canopy spectral reflectance (CSR) is a cost-effective, rapid, and non-destructive remote sensing and selection tool that can be employed in high throughput plant phenotypic studies. The objectives of the current study were to evaluate the predictive potential of vegetative indices as a high-throughput phenotyping tool for nitrogen use efficiency in soft red winter wheat (SRWW) (Triticum aestivum L.) and determine the optimum growth stage for employing CSR. A panel of 281 regionally developed SRWW genotypes was screened under low and normal N regimes in two crop seasons for grain yield, N uptake, nitrogen use efficiency for yield (NUEY) and nitrogen use efficiency for protein (NUEP). Vegetative indices were calculated from CSR and the data were analyzed by year and over the 2 years. Multiple regression and Pearson’s correlation were used to obtain the best predictive models and vegetative indices. The chosen models explained 84 and 83 % of total variation in grain yield and N uptake respectively, over two crop seasons. Models further accounted for 85 and 77 % of total variation in NUEY, and 85, and 81 % of total variation in NUEP under low and normal N conditions, respectively. In general, yield, NUEY and NUEP had greater than 0.6 R2 values in 2011–2012 but not in 2012–2013. Differences between years are likely a result of saturation of CSR indices due to high biomass and crop canopy coverage in 2012–2013. Heading was found to be the most appropriate crop growth stage to sense SRWW CSR data for predicting grain yield, N uptake, NUEY, and NUEP.

Northwest Arkansas (NWA) is a region of high-density confined animal feeding operations (CAFOs) that produces annual surpluses of poultry litter (PL) and municipal biosolids (BS) that can be used in organic fertilizer formulations. The objective of this study was to evaluate the effect of various binding agents and a nitrification inhibitor [dicyandiamide (DCD)] on granule physical strength and nutrient water solubility. We produced four different granule formulations using agglomeration techniques with a pin mixer in a 2 A— 2 A— 3 factorial arrangement. Treatments included PL granules with and without BS, with and without DCD, and bound with lignosulfonate, urea formaldehyde, or water. These 12 granular products were tested for bulk density, physical strength, and water-soluble N and P. Overall, granulated products were bulkier (0.48 to 0.64 g cm -3 ) than commercial urea fertilizer and BS (0.81 and 0.76 g cm -3 , respectively) but had a higher bulk density than fresh PL (0.40 g cm -3 ). Compared to urea and triple superphosphate (TSP) fertilizers, granules were more resistant to crumbling during force crush tests but degraded faster during attrition tests. Generally, the heat-dependent granulation process increased granule DRP concentrations by up to 278% compared to unprocessed ingredients. Based on ingredient and production costs, granules can be produced for $0.82 to $1.24 kg -1 N, similar to commercially available urea ($0.99 kg -1 N). Organic, granular fertilizers also contain other macro- and micronutrients that adds additional value to the formulations not accounted for in this study. Using the granulation process, significant amounts of PL and BS could economically be transported out of sensitive nutrient surplus watersheds in NWA to areas suffering from nutrient deficiencies.

The long-term effect of feeding the catecholamine analog ractopamine (RAC; ractopamine hydrochloride, Elanco Animal Health, Indianapolis, IN) on the expression of genes involved in energy and lipid metabolism in subcutaneous adipose tissue was studied. Large White pigs (84 kg) were fed corn- and soybean meal-based diets supplemented with 0, 20, or 60 mg/kg of RAC for 14, 28, or 42 d. Expression (mRNA abundance) in adipose tissue of sterol regulatory binding protein-1 (SREBP-1), PPARα, PPARγ2, fatty acid synthase (FAS), glucose transporter 4 (GLUT4), and stearoyl-CoA desaturase was determined by Northern blotting. Feed intakes did not differ, and RAC (20 and 60 mg/kg) improved BW gain at d 14, 28, and 42 (P < 0.05) and increased loin eye area (measured on d 42 only; P < 0.05). Expression of SREBP-1 and PPARγ2 declined (P < 0.05) with RAC by d 28 and 42, whereas expression of PPARα was increased (P < 0.05) on d 14, 28, and 42. After 14 d, expression of FAS and GLUT4 was decreased (P < 0.05) with 60 mg/kg of RAC, whereas both RAC concentrations attenuated FAS expression on d 28 and 42. Overall, adipose tissue stearoyl-CoA desaturase expression was not affected by RAC but showed somewhat less expression (P < 0.15) on d 28 at 60 mg/kg of RAC. Although prolonged, chronic RAC feeding most likely downregulates adipose tissue membrane β-adrenergic receptors, mRNA abundances of anabolic lipid metabolism transcription factors, glucose transporters, and enzymes (SREBP-1, PPARγ2, FAS, GLUT4) were still attenuated up to d 42. Conversely, a transcription factor related to oxidative metabolism expression (PPARα) was enhanced. We conclude that even after 42 d, RAC still decreased expression of lipogenic genes in adipose tissue by yet undefined cyclic adenosine monophosphate-directed mechanisms, but in contemporary lean pigs, this effect is likely of limited practical significance.

Variable rate nitrogen (N) application based on in-season remote sensing can potentially improve wheat (Triticum aestivum L.) N management and N use efficiency (NUE). The goal of this study was to evaluate the potential of improving in-season soft red winter wheat (SRWW) variable rate N recommendations based on crop canopy reflectance. Small-plot N rate response calibration studies guided development of the Virginia Wheat Algorithm (VWA) for grain yield prediction and variable rate N fertilizer rate determination for SRWW. Large plot, replicated validation studies conducted for 15 site-years included an N-rich strip installed at growth stage (GS) 25 and various treatments at GS 30; four or five fixed-rate treatments applied to evaluate site N response, a variable rate based on the VWA applied using a GreenSeeker® RT 200 system and a “standard” fixed rate based on GS 30 wheat tissue N concentration. All sites responded positively to GS 30 N application. When data from one site were excluded, rates were 8 and 3 kg ha−1 below the economically optimal N rate (EONR) for the VWA and standard methods, respectively. Based on these data, the GreenSeeker® RT 200 system employing the VWA was equivalent to the current standard method and offers real-time rate prescriptions with less labor and less delay than the current tissue N concentration sufficiency standard.

Land application of biosolids and poultry litter can benefit crop production by providing phosphorus (P) and other nutrients and organic matter. However, the bioavailability of applied P in those waste materials is directly dependent on the presence of specific P forms. In this study, we com

Phosphorus (P) loss from soils receiving manure has been strongly correlated to the water-extractable P (WEP) applied in the manure. Our main objective in this study was to assess the effects of different treatments (granulation alone and with urea, urea plus dicyandiamide, or hydrolyzed feathermeal) on WEP of poultry litter. We obtained poultry litters from two poultry farms located in the northwest Arkansas, and the selected litters were granulated in commercial granulating plants. During granulation, urea, urea plus dicyandiamide, and hydrolyzed feathermeal were added to poultry litters, which increased the total N:P ratio of litters up to 8.51. Results showed that granulated litters had greater amounts of WEP than raw and ground litters when measured at lower extraction ratio ( 0.75) with P in these poultry litters and granulates, suggesting that Mg-P minerals might control aqueous P concentrations in litter extracts. Based on these results, we recommend that WEP in poultry litter should be determined by using a 1:200 extraction ratio, followed by the use of Whatman No. 40 or 0.45 µm filters, and the filtrates can be preferably analyzed using inductively coupled plasma - optical emission spectroscopy (ICP-OES). In conclusion, this study shows that (1) granulation of poultry litter does not increase WEP of the poultry litter as given by 1:200 or 1:250 extraction ratios, and (2) addition of urea during granulation made the poultry litter a balanced fertilizer (N:P = 8:1) compared with raw litter (N:P = 1.35:1), which would help decrease P surpluses in intensive animal production areas when litters are land applied.

Infection with hepatitis C virus (HCV) causes chronic liver diseases. HCV-related liver damage is the main reason for liver transplantations in the western world. Spatial resolution is an aspect that has not yet been appreciated in current modeling simulations despite strong biological evidence that suggests intracellular spatial dependence is a crucial factor in the process the virus uses to replicate its RNA genome. HCV replication is believed to occur in specialized compartments within virus-infected cells, termed replication complexes, which are derived from altered regions (called the membranous web) of the endoplasmic reticulum (ER the ER is a central structure of each cell). Trafficking of both replication complexes, and their components, is likely a dynamic process occurring in three dimensions that is both difficult to capture experimentally and conceptually visualize. Therefore, we are developing a spatially-resolved biophysical model of HCV replication dynamics in single liver cells. We used data derived from 3D confocal microscopy of HCVinfected human hepatoma cells labeled for the ER membrane in order to reconstruct 3D geometries of single hepatocytes using NeuRA2. On top of these geometries, we developed a model using (surface) partial differential equation of viral RNA replication dynamics with particular emphasis upon RNA movement, viral protein production, cleavage and movement, and viral RNA replication within the membranous web. The arising (s)pde s on the ER surface are solved using the simulation platform UG4 within a Finite Volume framework combined with multigrid techniques. Our approach is based on two columns which are intended to grow together in the middle run: On the one hand side, we are doing parameter estimations of single components of viral replication based on the Gauss-Newton algorithm in order for extracting e.g. the diffusion constant of basic viral proteins on the surface of the ER using experimental FRAP time series. On the other hand side, we are developing the model which mimics the interplay of all important component of virus replication, e.g. viral RNA and various states of viral proteins. The estimated parameters are entering the model step by step. Therefore, the presented work is a practical application of the powerful tool UG4 and its multigrid techiques for the case of a huge number of DoFs (about 10) already at base level and demonstrates the excellent usability (and scalability) of UG4 in the context of modern biophysical research.

Denitrifying bioreactors (DNBRs) are an emerging technology used to remove nitrate-nitrogen (NO) from enriched waters by supporting denitrifying microorganisms with organic carbon in an anaerobic environment. Field-scale investigations have established successful removal of NO from agricultural drainage, but the potential for DNBRs to remediate excess phosphorus (P) exported from agricultural systems has not been addressed. We hypothesized that biochar addition to traditional woodchip DNBRs would enhance NO and P removal and reduce nitrous oxide (NO) emissions based on previous research demonstrating reduced leaching of NO and P and lower greenhouse gas production associated with biochar amendment of agricultural soils. Nine laboratory-scale DNBRs, a woodchip control, and eight different woodchip-biochar treatments were used to test the effect of biochar on nutrient removal. The biochar treatments constituted a full factorial design of three factors (biochar source material [feedstock], particle size, and application rate), each with two levels. Statistical analysis by repeated measures ANOVA showed a significant effect of biochar, time, and their interaction on NO and dissolved P removal. Average P removal of 65% was observed in the biochar treatments by 18 h, after which the concentrations remained stable, compared with an 8% increase in the control after 72 h. Biochar addition resulted in average NO removal of 86% after 18 h and 97% after 72 h, compared with only 13% at 18 h and 75% at 72 h in the control. Biochar addition also resulted in significantly lower NO production. These results suggest that biochar can reduce the design residence time by enhancing nutrient removal rates.

Two approaches for performing competitive binding immunoassays by HPLC and other flow-based systems are the simultaneous and sequential injection methods. Both these techniques make use of a column with a limited amount of antibody, onto which is injected a sample and a fixed amount of a labeled analyte analog. An indirect measure of the unlabeled analyte in the sample is then obtained by looking at the amount of analog in either the nonretained or retained peaks. In the simultaneous injection mode, the sample and labeled analog are applied at the same time to the column, while in the sequential mode the sample is injected first, followed by the analog. This results in a difference in the analytical characteristics of these two approaches. This study used chromatographic theory and previous data obtained for injections of human serum albumin (HSA) onto an anti-HSA antibody column to compare the response, detection limits, range, and sensitivity of these methods. Under equivalent conditions, it was found that the sequential method always provided the best lower limit of detection and sensitivity. However, the simultaneous mode had a broader dynamic range and higher upper limit of detection. From these observations, several guidelines were developed regarding the use and selection of such assays for new applications.

Continuous application of poultry litter (PL) significantly changes many soil properties, including soil test P (STP); Al, Fe, and Ca concentrations; and pH, which can affect the potential for P transport in surface runoff water. We conducted rainfall simulations on three historically acidic silt loam soils in Arkansas, Missouri, and Virginia to establish if long-term PL applications would affect soil inorganic P fractions and the resulting dissolved reactive P (DRP) in runoff water. Soil samples (0-5 cm depth) were taken to find sites ranging in Mehlich-3 STP from 20 to 1154 mg P kg. Simulated rainfall events were conducted on 3-m plots at 6.7 cm h, and runoff was collected for 30 min. Correlation between Mehlich-3 and runoff DRP indicated a linear relationship to 833 mg Mehlich-3 P kg. As Mehlich-3 STP increased, a concomitant increase in soil pH and Ca occurred on all soils. Soil P fractionation demonstrated that, as Mehlich-3 STP generally increased above 450 mg P kg (from high to very high), the easily soluble and loosely bound P fractions decreased by 3 to 10%. Water-insoluble complexes of P bound to Al and Ca were the main drivers in the reduction of DRP in runoff, accounting for up to 43 and 38% of total P, respectively. Basing runoff DRP concentration projections solely on Mehlich-3 STP may overestimate runoff P losses from soils receiving long-term PL applications due to dissolution of water-insoluble Ca-P compounds.

The specific roles of vascular endothelial growth factor (VEGF) family members and their receptors (VEGFRs) in coronary vessel formation were studied. By using the quail heart explant model, we found that neutralizing antibodies to VEGF-B or VEGF-C inhibited tube formation on the collagen gel more than anti–VEGF-A. Soluble VEGFR-1, a receptor for VEGF-A and -B, inhibited tube formation by 87%, a finding consistent with that of VEGF-B inhibition. In contrast, addition of soluble VEGFR-2, a receptor for VEGF family members A, C, D, and E, inhibited tube formation by only 43%. Acidic FGF-induced tube formation dependency on VEGF was demonstrated by the attenuating effect of a soluble VEGFR-1 and -2 chimera. The localization of VEGF R-2 and R-3 was demonstrated by in situ hybridization of serial sections, which documented marked accumulations of transcripts for both receptors at the base of the truncus arteriosus coinciding with the temporal and spatial formation of the coronary arteries by means of ingrowth of capillary plexuses. This finding suggests that both VEGFR-2 and R-3 may play a role in the formation of the coronary artery roots. In summary, these experiments document a role for multiple members of the VEGF family and their receptors in formation of the coronary vascular bed. © 2002 Wiley-Liss, Inc.

Summary In continuation of pharmacological investigations on polyphenolic compounds from the aerial parts of Galphimia glauca, flavonol acyl glycosides and gallic acid derivatives were screened in the classical and alternative complement assay. A reduction of complement-induced hemolysis was measured for quercetin-3-O-(2″-galloyl)-β-D-glucoside by 91.3 ± 1.76% (100 μM) and by 76.69 ± 4.43% (50 μM), respectively, and for quercetin-3-O-(6″-galloyl)-β-D-glucoside by 74.3 ± 6.77% (50 μM). Isoquercitrin, hyperoside, gallic acid, and ellagic acid inhibited the hemolysis to a much lower extent. In the alternative pathway quercetin-3-O-(2″-galloyl)-β-D-glucoside and quercetin-3-O-(2″-galloyl)-β-D-glucoside exhibited weaker inhibitory effects than in the classical pathway.

In a round robin experiment a set of five polycrystalline, metallic samples is studied by low-energy ion scattering (LEIS) in five different laboratories, The energy range is 0.6-3.5 keV and He and Ne ions are used. Even though different experimental setups are used the evaluated elemental sensitivity factors agree within +/-20%. Reproducibility within single laboratories is better than 10%. In an additional study carried out in three laboratories the surface composition of an alloy, Cu55Pd45, was determined, using in situ calibration standards, These surface composition measurements agreed within +/-3 at% demonstrating that quantitative composition determination is possible using this procedure. (C) 1998 Elsevier Science B.V. All rights reserved.

We report on the faceting of Cu(115) surfaces upon oxygen adsorption, as studied by scanning tunnelling microscopy. For temperatures around 500 K, during or after oxygen adsorption, pronounced faceting into (104), (014) and (113) facets is observed. Details of the facet structures were analyzed. The (113) facet exhibits an additional reconstruction which can be described as a c(7 × 12) superstructure. The development of CuOCu atomic chains is suggested to be the driving force for the oxygen-induced surface reconstruction.

Cryo-treatment of polymeric hydrogels, such as poly(vinyl alcohol) cryogels (PVA-C), have long been developed for a variety of medical applications. In the case of PVA-C the simplicity of its fabrication in its most basic form, obtained through a series of freezing and thawing cycles from low to room temperatures, along with its highly tailored microstructure, soft-tissue-like mechanical properties, and excellent biocompatibility makes it one of the most promising medical hydrogels researched today. In this chapter, we discuss the properties of soft tissues, with an emphasis on human vasculature, as a preamble for our investigation of current techniques in PVA-C manufacturing. The mechanical properties of PVA-C are then presented, outlining its behavior with varying cryo-treatments and PVA concentrations. We then highlight an example of PVA-C used for a coronary imaging phantom, and lastly provide brief examples of PVA-C and its derivatives in a variety of biomedical applications.

Solubility enhancement of the fungicide triflumicole byβ-cyclodextrin is explained using a thermodynamic approach. The influence of organic cosolvents on the overall equilibrium constants of triflumizole complexation withβ-cyclodextrin in aqueous solutions has been investigated. Their variance in mixed solvents is only partly explained by a competitive inclusion of substrate and cosolvent molecules inβ-cyclodextrin. The geometries of host-guest complexes have been estimated by molecular mechanics calculations. Their broad structural variety caused by the flexibility of host and guest molecules and different association possibilities of triflumizole have been analysed by a dynamic Monte Carlo docking method. The hydrophobic effect has been simulated by cominimization of the hydrophobic contributions to the solvation energy, calculated from the solvent accessible surface area of the complex and the conformational (potential) energy.

The solubility enhancement of triflumizole, a systemic fungicide, by β-cyclodextrin inclusion complexation was investigated by electron absorption spectroscopy. The respective association constant determined by different methods was estimated to 470±20M−1 in aqueous solution. A model for the host-guest complexation was deduced by molecular calculations.

Due to the availability of effective uricostatic (allopurinol), uricosuric (benzbromarone) and uricolytic (urate-oxidase) agents chronic polyarticular and tophaceous gout has become a very rare disease. The subject of this report came to our attention in 1993 and 1996 with severe debilitating gout and terminal renal failure despite continuous treatment with allopurinol for more than 20 years. Therefore he seemed to be an allopurinol nonresponder.

A key goal in improving the quality of vegetable oil is reducing its level of polyunsaturated fatty acids, linoleic (18:2) and linolenic (18:3), to result in an oxidatively-stable oil not requiring hydrogenation. This will result in reduced processing cost and the absense of trans fatty acids, by-products of hydrogenation believed to be unhealthy. Since canola and soybean germplasms with the desired low level of polyunsaturation are not currently available, at least, without an agronomic penalty, a transgenic approach was used.

An increased prevalence of apolipoprotein E (ApoE) epsilon 4 allele exists in late onset familial Alzheimer's disease. We found, in sporadic Alzheimer's disease, that 62% of patients possessed an ApoE-epsilon 4 allele, compared with 20% of controls. ApoE-epsilon 4/4 patients had more senile plaques (SPs) than epsilon 3/3 patients. ApoE immunoreactivity of SPs was equivalent in both groups. Two receptors bind ApoE complexes, the low density lipoprotein (LDL) receptor and the LDL receptor-related protein (LRP). In normal brain, anti-LRP antibodies strongly stained neurons and lightly stained astrocytes; anti-LDL receptor antibodies stained only the neuropil and astrocytes. In Alzheimer's disease, SPs and reactive astrocytes were also strongly LRP immunoreactive. Colocalization of ApoE and LRP to SPs implies that these molecules may be involved in metabolism of components of SPs.

1. A compound identified as orotidine has been found in the erythrocytes of all subjects on allopurinol. 2. The erythrocyte orotidine concentrations were much higher in patients with renal failure or with the Lesch-Nyhan syndrome. 3. In addition, increased amounts of oxypurinol-7-riboside were excreted in the urine by both of these groups compared with control subjects or with patients with normal renal function on allopurinol. 4. A good correlation was found between urinary oxypurinol-7-riboside excretion and erythrocyte orotidine concentrations. 5. Increased erythrocyte levels of the pyrimidine-sugar UDP-glucose were also found in patients with the highest orotidine levels. 6. The combined results suggest a derangement of pyrimidine nucleotide metabolism during allopurinol therapy. We propose that erythrocyte orotidine formation results primarily from inhibition of orotidine-5′-mono-phosphate decarboxylase by oxypurinol-7-ribotide.

We present Si L2,3 emission-band spectra of a series of 3d and 4d transition-metal (TM) silicides, together wtih Si K emission-band spectra of four 3d TM disilicides. The data are compared with augmented-spherical-wave density-of-states (DOS) calculations, and good agreement is found. The trends we find are explained with a general scheme for chemical bonding in TM silicides. The differences between the experimental data and the calculated DOS curves are tentatively attributed to self-energy effects.

An understanding of the genetic nature underlying tolerance to low-phosphorus (low-P) stress could aid in the efficient development of tolerant plant strains. The objective of this study was to identify the number of loci in a maize (Zea mays L.) population segregating for tolerance to low-P stress, their approximate location, and the magnitude of their effect.Seventy-seven restriction fragment length polymorphisms (RFLPs) were identified and scored in a maize F2 population derived from a cross between line NY821 and line H99. The F2 individuals were self-pollinated to produce F3 families. Ninety F3 families were grown in a sand-alumina system, which simulated diffusion-limited, low-P soil conditions. The F3 families were evaluated for vegetative growth in a controlled-environment experiment. To identify quantitative trait loci (QTLs) underlying tolerance to low-P stress, the mean phenotypic performances of the F3 families were contrasted based on genotypic classification at each of 77 RFLP marker loci.Six RFLP marker loci were significantly associated with performance under low-P stress (P0.01). One marker locus accounted for 25% of the total phenotypic variation. Additive gene action was predominant for all of the QTLs identified. Significant marker loci were located on four separate chromosomes representing five unlinked genomic regions. Two marker loci were associated with an additive by additive epistatic interaction. A multiple regression model including three marker loci and the significant epistatic interaction accounted for 46% of the total phenotypic variation. Heterozygosity per se was not predictive of phenotypic performance.

Genetic heterogeneity has been suggested in xanthinuria from the hitherto unexplained ability of some patients with this hereditary disorder to convert allopurinol to its active metabolite oxipurinol--an activity generally attributed to xanthine oxidase. This study provides evidence that the enzyme aldehyde oxidase is also deficient in xanthinuric patients not converting allopurinol to oxipurinol, whereas a xanthinuric patient with normal formation of oxipurinol had normal aldehyde oxidase activity. It is concluded that the enzyme aldehyde oxidase is the principal enzyme responsible for the formation of oxipurinol in man.

Due to the availability of effective uricostatic (allopurinol), uricosuric (benzbromarone) and uricolytic (urate-oxidase) agents chronic polyarticular and tophaceous gout has become a very rare disease. The subject of this report came to our attention in 1993 and 1996 with severe debilitating gout and terminal renal failure despite continuous treatment with allopurinol for more than 20 years. Therefore he seemed to be an allopurinol nonresponder.

It has been previously observed that single chick embryonic limb mesenchymal cells can differentiate into chondrocytes without cell-cell interactions when cultured in collagen or agarose gels. In the present study, limb ectoderm, but not dermis, inhibits chondrogenesis when placed on such collagen gel cultures. The inhibitory influence can be transmitted extensive distances in the gel, even when the ectoderm is placed on a porous filter. Collagen gels, preconditioned with limb ectoderms, are also inhibitory to chondrogenesis. On the other hand, chondrogenesis is less inhibited by ectoderm when the mesenchymal cells are placed in agarose. These results suggest that the antichondrogenic effect of limb ectoderm is mediated through alterations of the collagenous extracellular matrix and support the idea that the extracellular matrix must be considered as an organized, functional unit capable of regulating cell differentiation.

dATP, dADP, and dAMP equalled or exceeded the depleted levels of ATP, ADP, and AMP in erythrocytes from two children with adenosine deaminase (ADA; EC 3.5.4.4) deficiency. dATP and dADP were identified in the mononuclear cells of only one child. The levels of deoxyadenosine compounds fell dramatically after enzyme replacement therapy and were no longer detectable in the urine or in mononuclear cells. Erythrocyte adenosine nucleotide levels showed a corresponding increase. Intact erythrocytes prior to treatment contained adenine, presumed to be from deoxyadenosine degraded during extraction. Adenosine at high concentrations in vitro increased both dATP and ATP levels and decreased intracellular deoxyadenosine levels. There was no significant deamination of either [8-14C]adenosine or deoxyadenosine by intact ADA-deficient erythrocytes. About 90% of adenosine was metabolized to ATP at substrate concentrations from 10-100 microM, compared to 40-60% of deoxyadenosine metabolized to dATP. These studies suggest that (i) high intracellular deoxyadenosine levels may be necessary in vivo to sustain the raised dATP levels in ADA deficiency. (ii) When ADA is inhibited or absent, deoxyadenosine is removed rapidly from the circulation by the human erythrocyte utilizing an adenosine transport system linked to both ADA and adenosine kinase (EC 2.7.1.20).

Two distinct types of cells were derived from organ cultures of liver from adult and larval Xenopus laevis. Each type was isolated in clonal cell culture. Several media were compared with respect to support of epithelioid outgrowths from explants and support of growth of epithelioid colonies in cell culture. Ultracentrifuged embryo extract promotes the growth of all cell types, but the particulate fraction is also required for the maintenance of the epithelioid morphology of larval cells. In these media it was possible to maintain some epithelioid cell cultures for over 6 months. The identity and retention of some specialized functions of both cell types were demonstrated on larval cells. One cell type contained PAS-stainable, amylase-sensitive granules that increased in amount after treatment with glucocorticoids. This same type was shown by histochemical methods to contain phosphorylase, glucose-6-phosphatase, and dexamethasone-inducible tyrosine aminotransferase, and is considered to be a hepatocyte. The second type appears to be a sinusoidal cell, since it phagocytosed trypan blue and stained positively for acid phosphatase.

The process of determination is studied by using a cell culture system derived from dissociated chick embryo limb buds. When limb bud cells obtained from embryos younger than stage 25 (undertermined) are temporarily prevented from passing through the cell cycle (either by maintaining the cells on a petri dish or in the presence of high concentrations of cyclic AMP, both of which depress thymidine-H 3 incorporation), some cells subsequently form cartilage colonies. These results support the hypothesis that a temporary block at some stage in the cell cycle causes mesoblasts to acquire the capacity to differentiate into cartilage cells.

During collaborative studies of purine metabolism in PNP and ADA deficiency2, we investigated ‘lymphocyte’ (peripheral blood mononuclear cells-PBMs) nucleotide levels and found consistently low ATP:ADP ratios in both patient and controls. Values quoted in the literature for total nucleotides and ATP/ADP ratios also varied widely3,4. For this reason experiments to investigate these differences and establish a range for PBM nucleotide levels in the local population were undertaken.