731 research outputs found

    Right Rate, Timing, Source and Placement: More Bang for the Pasture Fertilizer Buck

    Get PDF
    As we write this paper for the conference, fall fertilizer prices continue to increase, albeit at a slower pace than earlier this fall for most materials. The latest DTN retail price survey https://www.dtnpf.com/agriculture/web/ag/crops/article/2021/10/06/fertilizer‐price‐gains-losing‐steam has urea (46‐0‐0) at 620/ton,DAP(18460)at620/ton, DAP (18‐46‐0) at 722/ton and potash (0‐ 0‐60) at 647/ton.Thisgives647/ton. This gives 0.675/lb N, 0.52/lbP2O5(aftertheNvalueinDAPpricewasaccountedfor),and0.52/lb P2O5 (after the N value in DAP price was accounted for), and 0.54/lb K2O. Compared to this time last year, urea, DAP and muriate of potash are 71, 64 and 92% higher, respectively. Other important materials used in Kentucky are also higher: ammonium polyphosphate (APP, 10‐34‐0); UAN (32‐0‐0); and anhydrous (82‐0‐0) are 40, 78 and 84% more expensive, respectively

    Hepatoma cell density promotes claudin-1 and scavenger receptor BI expression and hepatitis C virus internalization.

    Get PDF
    Hepatitis C virus (HCV) entry occurs via a pH- and clathrin-dependent endocytic pathway and requires a number of cellular factors, including CD81, the tight-junction proteins claudin 1 (CLDN1) and occludin, and scavenger receptor class B member I (SR-BI). HCV tropism is restricted to the liver, where hepatocytes are tightly packed. Here, we demonstrate that SR-BI and CLDN1 expression is modulated in confluent human hepatoma cells, with both receptors being enriched at cell-cell junctions. Cellular contact increased HCV pseudoparticle (HCVpp) and HCV particle (HCVcc) infection and accelerated the internalization of cell-bound HCVcc, suggesting that the cell contact modulation of receptor levels may facilitate the assembly of receptor complexes required for virus internalization. CLDN1 overexpression in subconfluent cells was unable to recapitulate this effect, whereas increased SR-BI expression enhanced HCVpp entry and HCVcc internalization, demonstrating a rate-limiting role for SR-BI in HCV internalization

    Building a mechanistic mathematical model of hepatitis C virus entry.

    Get PDF
    The mechanism by which hepatitis C virus (HCV) gains entry into cells is a complex one, involving a broad range of host proteins. Entry is a critical phase of the viral lifecycle, and a potential target for therapeutic or vaccine-mediated intervention. However, the mechanics of HCV entry remain poorly understood. Here we describe a novel computational model of viral entry, encompassing the relationship between HCV and the key host receptors CD81 and SR-B1. We conduct experiments to thoroughly quantify the influence of an increase or decrease in receptor availability upon the extent of viral entry. We use these data to build and parameterise a mathematical model, which we then validate by further experiments. Our results are consistent with sequential HCV-receptor interactions, whereby initial interaction between the HCV E2 glycoprotein and SR-B1 facilitates the accumulation CD81 receptors, leading to viral entry. However, we also demonstrate that a small minority of viruses can achieve entry in the absence of SR-B1. Our model estimates the impact of the different obstacles that viruses must surmount to achieve entry; among virus particles attaching to the cell surface, around one third of viruses accumulate sufficient CD81 receptors, of which 4-8% then complete the subsequent steps to achieve productive infection. Furthermore, we make estimates of receptor stoichiometry; in excess of 10 receptors are likely to be required to achieve viral entry. Our model provides a tool to investigate the entry characteristics of HCV variants and outlines a framework for future quantitative studies of the multi-receptor dynamics of HCV entry.Wellcome, Royal Society, Newton Trus

    It Takes More Than Calcium to Neutralize Soil Acidity

    Get PDF
    Proper pH management is the foundation to a good soil fertility program. Soil pH influences nutrient availability and root growth and function. Just because an agricultural product contains calcium does not mean that it will change soil pH. The effectiveness of three calcium products in raising soil pH was compared to an untreated check in acid soils. A field trial was conducted at 16 locations across Kentucky and a laboratory incubation study was conducted at the University of Kentucky Research and Education Center. The same application rates were used for the three products, whether in field trials or laboratory incubations. The rates were 46.8 L ha-1 for the liquid calcium and 4.5 Mg ha-1 for the pelletized and ag limes. The field studies exhibited higher soil pH at 3-month and 12-month sample dates with ag lime and pelletized lime treatments than with the check and liquid calcium treatments. The lab study exhibited higher soil pH values at each sample date (1, 3, 6 and 12 month) with ag lime and pelletized lime than with check and liquid calcium. The soil pH was not improved with the addition of liquid calcium (chloride) and results of this study are supported by the chemical foundations of soil acidity neutralization reactions - calcium chloride does not neutralize acidity and calcium carbonates do

    A Long View of Polluting Industry and Environmental Justice in Baltimore

    Get PDF
    Purpose This study examines the density of polluting industry by neighborhoods in Baltimore over the long term, from 1950 to 2010, to determine if high pollution burdens correspond spatially with expected demographic and housing variables predicted in the environmental justice literature. For 1960–1980 we use data on heavy industry from Dun and Bradstreet directories and for 1990–2010 the US EPA’s Toxics Release Inventory to calculate a Hazards Density Index. Drawing on the decennial censuses for 1960–2010, we populate census tracts from corresponding years with data on race, ethnicity, educational attainment, income, and housing tenure. Findings Density of polluting industry is positively correlated with low-income neighborhoods and renter-occupied housing in 1960 and by 2010 with white, Hispanic, and low educational attainment populations. In general, over time density of polluting facilities shifts from an association with wealth to race and ethnicity while educational attainment remains a significant variable throughout. This study confirms earlier analyses on Baltimore that white neighborhoods are more likely than African–American neighborhoods (1990–2010) to contain polluting facilities but reveals for the first time that educational attainment is also significant. The paper concludes with a discussion of the Baltimore Sustainability Plan and its weak efforts to address persistent environmental injustices

    Grinding of riblets with "beaver tooth" multi-layer tools

    Get PDF
    To reduce friction in turbo machinery components, riblets are induced on compressor blades or pump impellers. Here, the grinding process enables a higher productivity in machining of riblet structures compared to knurling, laser or milling operations. Usually, profiled grinding tools are used to create such structures inspired by sharkskin. Unfortunately, conventional grinding tools have to be dressed continuously to keep the desired profile in the circumferential surface. To avoid the time-consuming dressing process and to enable a self-sharpening effect, an innovative multi-layer tool concept is developed. The tool consists of two types of thin polyimide layers. The first type contains abrasives and the second is a support layer without abrasives. These layers are piled alternately in a special manufacturing process and act like a monolithic tool in grinding process. The aim of the investigations presented in this paper is to find an optimal parameter setting to produce riblet structures productively by using the self-sharpening effect. The optimal setting allows a grinding process without any dressing process by using a large part of the grinding tool volume. At first, the manufacturing process is focused to create clearly divided support and abrasive layers of the grinding tool. Furthermore, the investigation shows the relationship between grinding parameters and the setback of the supporting layer in the middle of the tool. This setback is important for the creation of riblet structures in the surface of AISI 420 workpieces

    Assessing the Nutrient Status of Alfalfa Stands in Kentucky

    Get PDF
    Alfalfa (Medicago sativa L.) is a perennial forage legume and is sometimes referred to as the “Queen of Forages” due to its high nutritional value. Alfalfa is commonly produced as hay for use in the dairy and equine industries. Alfalfa yield increased exponentially from the 1950s to the1980s due to new breeding and management innovations. However, during the 1980s yields plateaued at around 7.5 Mg/ha and remain there today. The overarching goal of this study was to determine the role of soil fertility in the observed yield plateau. Fifty alfalfa stands in Kentucky were sampled to gather information about their macro and micronutrient status. Samples were taken, when the stand reached the late bud to early flower stage of maturity, from a 6 x 6 m2 area that was representative of the entire stand. Soil samples were collected to 10 and 15 cm depths and were sent to the University of Kentucky soil testing lab for analysis. The top 15 cm of 30 stems were dried, ground, and sent to Kansas State University for tissue analysis. In 2022, soil and tissue data from the alfalfa stands sampled indicated that potassium, sulfur, and magnesium were the nutrients most commonly reported to be below established sufficiency ranges. In addition, pH was low in just under half of the sampled stands. Tissue analysis indicated that soil testing overestimated potassium deficiencies in alfalfa stands in Kentucky. Even so, potassium levels were below the sufficiency range in nearly one-fourth of the alfalfa stands sampled

    Thermally Activated Magnetization and Resistance Decay during Near Ambient Temperature Aging of Co Nanoflakes in a Confining Semi-metallic Environment

    Full text link
    We report the observation of magnetic and resistive aging in a self assembled nanoparticle system produced in a multilayer Co/Sb sandwich. The aging decays are characterized by an initial slow decay followed by a more rapid decay in both the magnetization and resistance. The decays are large accounting for almost 70% of the magnetization and almost 40% of the resistance for samples deposited at 35 oC^oC. For samples deposited at 50 oC^oC the magnetization decay accounts for 50\sim 50% of the magnetization and 50% of the resistance. During the more rapid part of the decay, the concavity of the slope of the decay changes sign and this inflection point can be used to provide a characteristic time. The characteristic time is strongly and systematically temperature dependent, ranging from 1\sim1x102s10^2 s at 400K to 3\sim3x105s10^5 s at 320K in samples deposited at 35oC35 ^oC. Samples deposited at 50 oC^oC displayed a 7-8 fold increase in the characteristic time (compared to the 35oC35 ^oC samples) for a given aging temperature, indicating that this timescale may be tunable. Both the temperature scale and time scales are in potentially useful regimes. Pre-Aging, Scanning Tunneling Microscopy (STM) reveals that the Co forms in nanoscale flakes. During aging the nanoflakes melt and migrate into each other in an anisotropic fashion forming elongated Co nanowires. This aging behavior occurs within a confined environment of the enveloping Sb layers. The relationship between the characteristic time and aging temperature fits an Arrhenius law indicating activated dynamics

    Neurolinguistic programming: a systematic review of the effects on health outcomes

    Get PDF
    BACKGROUND: Neurolinguistic programming (NLP) in health care has captured the interest of doctors, healthcare professionals, and managers. AIM: To evaluate the effects of NLP on health-related outcomes. DESIGN AND SETTING: Systematic review of experimental studies. METHOD: The following data sources were searched: MEDLINE, PsycINFO, ASSIA, AMED, CINAHL, Web of Knowledge, CENTRAL, NLP specialist databases, reference lists, review articles, and NLP professional associations, training providers, and research groups. RESULTS: Searches revealed 1459 titles from which 10 experimental studies were included. Five studies were randomised controlled trials (RCTs) and five were pre-post studies. Targeted health conditions were anxiety disorders, weight maintenance, morning sickness, substance misuse, and claustrophobia during MRI scanning. NLP interventions were mainly delivered across 4-20 sessions although three were single session. Eighteen outcomes were reported and the RCT sample sizes ranged from 22 to 106. Four RCTs reported no significant between group differences with the fifth finding in favour of the NLP arm (F = 8.114, P<0.001). Three RCTs and five pre-post studies reported within group improvements. Risk of bias across all studies was high or uncertain. CONCLUSION: There is little evidence that NLP interventions improve health-related outcomes. This conclusion reflects the limited quantity and quality of NLP research, rather than robust evidence of no effect. There is currently insufficient evidence to support the allocation of NHS resources to NLP activities outside of research purposes

    Association of the tumour necrosis factor alpha -308 but not the interleukin 10 -627 promoter polymorphism with genetic susceptibility to primary sclerosing cholangitis

    Full text link
    BACKGROUND AND AIMS Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown aetiology. Abnormalities in immune regulation and genetic associations suggest that PSC is an immune mediated disease. Several polymorphisms within the tumour necrosis factor α (TNF-α) and interleukin 10 (IL-10) promoter genes have been described which influence expression of these cytokines. This study examines the possible association between polymorphisms at the −308 and −627 positions in the TNF-α and IL-10 promoter genes, respectively, and susceptibility to PSC. METHODS TNF-α −308 genotypes were studied by polymerase chain reaction (PCR) in 160 PSC patients from Norway and the UK compared with 145 ethnically matched controls. IL-10 −627 genotypes were studied by PCR in 90 PSC patients compared with 84 ethnically matched controls. RESULTS A total of 16% of Norwegian PSC patients and 12% of British PSC patients were homozygous for the TNF2 allele compared with 3% and 6% of respective controls. The TNF2 allele was present in 60% of PSC patients versus 30% of controls (ORcombined data=3.2 (95% confidence intervals (CI) 1.8–4.5); pcorr=10−5). The association between the TNF2 allele and susceptibility to PSC was independent of the presence of concurrent inflammatory bowel disease (IBD) in the PSC patients; 61% of PSC patients without IBD had TNF2 compared with 30% of controls (ORcombined data=3.2 (95% CI 1.2–9.0); pcorr=0.006 ). There was no difference in the −627 IL-10 polymorphism distributions between patients and controls in either population. The increase in TNF2 allele in PSC patients only occurs in the presence of DRB1*0301 (DR3) and B8. In the combined population data, DRB1*0301 showed a stronger association with susceptibility to PSC than both the TNF2 and B8 alleles (ORcombined data=3.8, pcorr=10−6 v ORcombined data=3.2, pcorr=10−5 vORcombined data =3.41, pcorr=10−4, respectively). CONCLUSIONS This study identified a significant association between possession of the TNF2 allele, a G→A substitution at position −308 in the TNF-α promoter, and susceptibility to PSC. This association was secondary to the association of PSC with the A1-B8-DRB1*0301-DQA1*0501-DQB1*0201 haplotype. No association was found between the IL-10 −627 promoter polymorphism and PSC
    corecore