696 research outputs found

    Scale economies and technological change in Federal Reserve ACH payment processing

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    An analysis of the contribution of scale economies, technological change, and falling input prices to the absolute reduction in the real processing costs of an ACH transfer over the 1979-94 period.Clearinghouses (Banking)

    Estimates of scale and cost efficiency for Federal Reserve currency operations

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    Meeting the currency demands of depository institutions, businesses, and consumers costs the Federal Reserve more than half a billion dollars each year, yet, very little research has been devoted to understanding what factors affect such costs. The authors estimate a cost function in order to obtain estimates of scale and cost efficiency for this service. They find that as in other paper-based technologies, such as checks, scale economies are achieved at a relatively low level of output, implying that currency services are not a natural monopoly. They also provide estimates of facility-specific marginal costs and returns to scale measures that could be used to improve resource allocations. Lastly, they find that the average processing facility operates at more 80 percent of the efficiency of the “best practice” facility, comparable to cost efficiency estimates that have been reported elsewhere for private-sector financial institutions.Federal Reserve banks - Costs ; Payment systems

    p21-Activated Kinase 1 (Pak1) Phosphorylates BAD Directly at Serine 111 In Vitro and Indirectly through Raf-1 at Serine 112

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    Cell survival depends on the balance between protective and apoptotic signals. When the balance of signals tips towards apoptosis, cells undergo programmed cell death. This balance has profound implications in diseases including cancer. Oncogenes and tumor suppressors are mutated to promote cell survival during tumor development, and many chemotherapeutic drugs kill tumor cells by stimulating apoptosis. BAD is a pro-apoptotic member of the Bcl-2 family of proteins, which can be phosphorylated on numerous sites to modulate binding to Bcl-2 and 14-3-3 proteins and inhibit its pro-apoptotic activities. One of the critical phosphorylation sites is the serine 112 (S112), which can be phosphorylated by several kinases including Pak1.We mapped the Pak phosphorylation sites by making serine to alanine mutations in BAD and testing them as substrates in in vitro kinase assays. We found that the primary phosphorylation site is not S112 but serine 111 (S111), a site that is sometimes found phosphorylated in vivo. In transfection assays of HEK293T cells, we showed that Pak1 required Raf-1 to stimulate phosphorylation on S112. Mutating either S111 or S112 to alanine enhanced binding to Bcl-2, but the double mutant S111/112A bound better to Bcl-2. Moreover, BAD phosphorylation at S111 was observed in several other cell lines, and treating one of them with the Pak1 inhibitor 2,2'-Dihydroxy-1,1'-dinaphthyldisulfide (IPA-3) reduced phosphorylation primarily at S112 and to a smaller extent at S111, while Raf inhibitors only reduced phosphorylation at S112.Together, these findings demonstrate that Pak1 phosphorylates BAD directly at S111, but phosphorylated S112 through Raf-1. These two sites of BAD serve as redundant regulatory sites for Bcl-2 binding

    Variable Renewable Energy in Modeling Climate Change Mitigation Scenarios

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    This paper addresses the issue of how to account for short‐term temporal variability of renewable energy sources and power demand in long‐term climate change mitigation scenarios in energy‐economic models. An approach that captures in a stylized way the major challenges to the integration of variable renewable energy sources into power systems has been developed. As a first application this approach has been introduced to REMIND‐D, a hybrid energy‐economy model of Germany. An approximation of the residual load duration curve is implemented. The approximating function endogenously changes depending on the penetration and mix of variable renewable power. The approach can thus be used to account for variability and correlations between different sources of renewable supply and power demand within the intertemporal optimization of long‐term (energy system) investment decisions in climate change mitigation scenarios. Moreover, additional constraints are introduced to account for flexibility requirements concerning loadfollowing and ancillary services. The parameterization is validated with MICOES a highly resolved dispatch model. Model results show that significant changes are induced when the new residual load duration curve methodology is implemented. With variability, scenarios show that the German power sector is no longer fully decarbonized because natural gas combined‐cycle plants are built to complement renewable energy generation. The mitigation costs increase by about 20% compared to a model version in which variability is not taken into account

    Influence of small-scale spatial variability of soil properties on yield formation of winter wheat

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    Background: With the increasing development of sophisticated precision farming techniques, high-resolution application maps are frequently discussed as a key factor in increasing yield potential. However, yield potential maps based on multiple soil properties measurements are rarely part of current farming practices. Furthermore, small-scale differences in soil properties have not been taken into account. Methods: To investigate the impact of soil property changes at high resolution on yield, a field trial has been divided into a sampling grid of 42 plots. The soil properties in each plot were determined at three soil depths. Grain yield and yield formation of winter wheat were analyzed at two sites. Results: Multiple regression analyses of soil properties with yield measures showed that the soil contents of organic carbon, silt, and clay in the top and subsoil explained 45–46% of the variability in grain yield. However, an increasing clay content in the topsoil correlated positively with grain yield and tiller density. In contrast, a higher clay content in the subsoil led to a decrease in grain yield. A cluster analysis of soil texture was deployed to evaluate whether the soil´s small-scale differences caused crucial differences in yield formation. Significant differences in soil organic carbon, yield, and yield formation were observed among clusters in each soil depth. Conclusion: These results show that small-scale lateral and vertical differences in soil properties can strongly impact crop yields and should be considered to improve site-specific cropping techniques further

    Soil nitrogen and water management by winter-killed catch crops

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    Improving N cycling in agroecosystems is one of the key challenges in reducing the environmental footprint of agriculture. Further, uncertainty in precipitation makes crop water management relevant in regions where it has not been necessary thus far. Here, we focus on the potential of winter-killed catch crops (CCs) to reduce N leaching losses from N mineralization over the winter and from soil water management. We compared four single CCs (white mustard, phacelia, Egyptian clover and bristle oat) and two CC mixtures with 4 and 12 plant species (Mix4 and Mix12) with a fallow treatment. High-resolution soil mineral N (Nmin) monitoring in combination with the modelling of spatiotemporal dynamics served to assess N cycling under winter-killed CCs, while soil water was continuously monitored in the rooting zone. Catch crops depleted the residual Nmin pools by between 40 % and 72 % compared to the fallow. The amount of residual N uptake was lowest for clover and not significantly different among the other CCs. Catch crops that produce high N litter materials, such as clover and mustard leaves, showed an early N mineralization flush immediately after their termination and the highest leaching losses from litter mineralization over the winter. Except for clover, all CCs showed Nmin values between 18 % and 92 % higher on the sowing date of the following maize crop. However, only Mix12 was statistically significant. Catch crops depleted the soil water storage in the rooting zone during their growth in autumn and early winter, but preserved water later on when their residues covered the ground. The shallow incorporation of CC residues increased water storage capacity during the cropping season of the main crop even under reduced soil water availability. Hence, catch cropping is not just a simple plant cover for the winter but improves the growth conditions for the following crop with decreased N losses. Mixtures have been shown to compensate for the weaknesses of individual CC species in terms of nutrient capture, mineralization and transfer to the following main crop as well as for soil water management. Detailed knowledge about plant performance during growth and litter mineralization patterns is necessary to make optimal use of their potential

    Antibiofilm Activity of the Brown Alga Halidrys siliquosa against Clinically Relevant Human Pathogens.

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    The marine brown alga Halidrys siliquosa is known to produce compounds with antifouling activity against several marine bacteria. The aim of this study was to evaluate the antimicrobial and antibiofilm activity of organic extracts obtained from the marine brown alga H. siliquosa against a focused panel of clinically relevant human pathogens commonly associated with biofilm-related infections. The partially fractionated methanolic extract obtained from H. siliquosa collected along the shores of Co. Donegal; Ireland; displayed antimicrobial activity against bacteria of the genus Staphylococcus; Streptococcus; Enterococcus; Pseudomonas; Stenotrophomonas; and Chromobacterium with MIC and MBC values ranging from 0.0391 to 5 mg/mL. Biofilms of S. aureus MRSA were found to be susceptible to the algal methanolic extract with MBEC values ranging from 1.25 mg/mL to 5 mg/mL respectively. Confocal laser scanning microscopy using LIVE/DEAD staining confirmed the antimicrobial nature of the antibiofilm activity observed using the MBEC assay. A bioassay-guided fractionation method was developed yielding 10 active fractions from which to perform purification and structural elucidation of clinically-relevant antibiofilm compounds

    Catch crop mixtures have higher potential for nutrient carry-over than pure stands under changing environments

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    Winter catch crops are grown to scavenge nutrients over a period of unfavorable growth conditions and to conserve nutrients for subsequent release to the following main crop. Since environmental conditions have a strong impact on the growth and nutrient capture in roots and shoots of individual catch crop species, we anticipated that mixtures will be more durable and efficient in nutrient capture due to compensatory effects among component species. We tested this hypothesis and determined the nitrogen and phosphorus accumulation in the shoots and roots of four catch crop species grown in pure vs. mixed stands at two sites for two or three years. Element concentrations were determined in the root and shoot biomass of each species and used to calculate the nutrient pool fixed in the root or shoot biomass. A qPCR-based technique was applied to quantify the root biomass of individual species based on species-specific DNA sequences. Despite considerable variation across environments, the overall plant biomass of white mustard (Sinapis alba), lacy phacelia (Phacelia tanacetifolia) and bristle oat (Avena strigosa) was similar and higher than that of Egyptian clover (Trifolium alexandrinum). While pure stands varied 6- to 24-fold in shoot biomass depending on environmental conditions, the variation was only ~3-fold for catch crop mixtures, with less pronounced variation in the root biomass. In general, the root biomass was comparable to the shoot biomass in each species. Roots contributed 26–46% of the nitrogen and 36–48% of the phosphorus to the total accumulation of these nutrients in the catch crop biomass, thus emphasizing the importance of plant roots as belowground nutrient pool for potential carry-over of nutrients to the subsequent crop. Although the mixture was mostly dominated by two of the four species, namely mustard and phacelia, it captured similar or even larger amounts of nutrients than the best-performing pure stand under any growth condition. This was the case for shoot- and for root-bound nutrients. Our results indicate that catch crop mixtures have higher durability than pure cultures to environmental variations. The amount of nitrogen captured by the mixture meets the average postharvest nitrogen that is left over by a wide range of cash crops, thus emphasizing that catch crop mixtures represent an efficient nutrient management tool in crop rotations. © 202

    The Impact of Video-Based Microinterventions on Attitudes Toward Mental Health and Help Seeking in Youth: Web-Based Randomized Controlled Trial.

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    BACKGROUND Mental health (MH) problems in youth are prevalent, burdening, and frequently persistent. Despite the existence of effective treatment, the uptake of professional help is low, particularly due to attitudinal barriers. OBJECTIVE This study evaluated the effectiveness and acceptability of 2 video-based microinterventions aimed at reducing barriers to MH treatment and increasing the likelihood of seeking professional help in young people. METHODS This study was entirely web based and open access. The interventions addressed 5 MH problems: generalized anxiety disorder, depression, bulimia, nonsuicidal self-injury, and problematic alcohol use. Intervention 1 aimed to destigmatize and improve MH literacy, whereas intervention 2 aimed to induce positive outcome expectancies regarding professional help seeking. Of the 2435 participants who commenced the study, a final sample of 1394 (57.25%) participants aged 14 to 29 years with complete data and sufficient durations of stay on the video pages were randomized in a fully automated manner to 1 of the 5 MH problems and 1 of 3 conditions (control, intervention 1, and intervention 2) in a permuted block design. After the presentation of a video vignette, no further videos were shown to the control group, whereas a second, short intervention video was presented to the intervention 1 and 2 groups. Intervention effects on self-reported potential professional help seeking (primary outcome), stigma, and attitudes toward help seeking were examined using analyses of covariance across and within the 5 MH problems. Furthermore, we assessed video acceptability. RESULTS No significant group effects on potential professional help seeking were found in the total sample (F2,1385=0.99; P=.37). However, the groups differed significantly with regard to stigma outcomes and the likelihood of seeking informal help (F2,1385=3.75; P=.02). Furthermore, separate analyses indicated substantial differences in intervention effects among the 5 MH problems. CONCLUSIONS Interventions to promote help seeking for MH problems may require disorder-specific approaches. The study results can inform future research and public health campaigns addressing adolescents and young adults. TRIAL REGISTRATION German Clinical Trials Register DRKS00023110; https://drks.de/search/de/trial/DRKS00023110
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