954 research outputs found

    Are the causes of bank distress changing? can researchers keep up?

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    Since 1990, the banking sector has experienced enormous legislative, technological and financial changes, yet research into the causes of bank distress has slowed. One consequence is that current supervisory surveillance models may no longer accurately represent the banking environment. After reviewing the history of these models, we provide empirical evidence that the characteristics of failing banks has changed in the last ten years and argue that the time is right for new research employing new empirical techniques. In particular, dynamic models that utilize forward-looking variables and address various types of bank risk individually are promising lines of inquiry. Supervisory agencies have begun to move in these directions, and we describe several examples of this new generation of early-warning models that are not yet widely known among academic banking economists.Bank failures ; Bank supervision

    Are the causes of bank distress changing? can researchers keep up?

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    Since 1990, the banking sector has experienced enormous legislative, technological, and financial changes, yet research into the causes of bank distress has slowed. One consequence is that traditional supervisory surveillance models may not capture important risks inherent in the current banking environment. After reviewing the history of these models, the authors provide empirical evidence that the characteristics of failing banks have changed in the past ten years and argue that the time is right for new research that employs new empirical techniques. In particular, dynamic models that use forward-looking variables and address various types of bank risk individually are promising lines of inquiry. Supervisory agencies have begun to move in these directions, and the authors describe several examples of this new generation of early-warning models that are not yet widely known among academic banking economists.Bank supervision ; Risk management

    Cultivation and enrichment of anammox culture in a submerged membrane bioreactor

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    Results of a research project comparing membrane fouling rates of PVDF to PTFE membrane

    Reduction of blade-vortex interaction noise using higher harmonic pitch control

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    An acoustics test using an aeroelastically scaled rotor was conducted to examine the effectiveness of higher harmonic blade pitch control for the reduction of impulsive blade-vortex interaction (BVI) noise. A four-bladed, 110 in. diameter, articulated rotor model was tested in a heavy gas (Freon-12) medium in Langley's Transonic Dynamics Tunnel. Noise and vibration measurements were made for a range of matched flight conditions, where prescribed (open-loop) higher harmonic pitch was superimposed on the normal (baseline) collective and cyclic trim pitch. For the inflow-microphone noise measurements, advantage was taken of the reverberance in the hard walled tunnel by using a sound power determination approach. Initial findings from on-line data processing for three of the test microphones are reported for a 4/rev (4P) collective pitch control for a range of input amplitudes and phases. By comparing these results to corresponding baseline (no control) conditions, significant noise reductions (4 to 5 dB) were found for low-speed descent conditions, where helicopter BVI noise is most intense. For other rotor flight conditions, the overall noise was found to increase. All cases show increased vibration levels

    Prospect of Hydroxyl Radical Exposure during Seawater Bathing to Treat Amoebic Gill Disease in Atlantic Salmon

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    This study aims to undertake hydroxyl (.OH) radical-based preliminary investigations with a view to utilising seawater as a viable alternative to freshwater for the treatment of amoebic gill disease (AGD) in aquaculture industries. The study presents in vitro viability studies of clonal amoebae species to examine the effects of .OH radicals on both parasites and hosts. The study also assesses the toxicity to Chinook salmon cell lines (CHSE-214) in freshwater and 35 ppt seawater via continuous dosing of 35 mM .OH radicals and hydrogen peroxide (H2O2) for 1.5 to 4 hr, separately at 18°C and 15°C. Comparatively high viability of CHSE-214 (60% in .OH and 50% in H2O2) for a prolonged treatment of up to 4 hr in seawater at 15°C indicates suitability of low seawater temperature while using either .OH or H2O2 during bathing. The viability of CHSE-214 remained relatively stable in seawater (55%–60% in .OH and 50%–60% in H2O2), at both temperatures of 18°C and 15°C. However, at 15°C, a drastic reduction of viability of CHSE-214 in freshwater (from 80% to 48% in .OH and from 70% to 58% in H2O2) has indicated high variations in toxicity levels in freshwater at low temperature. Using DNA staining agents in flow cytometry, the in vitro viability study results in >22.5% mortality of clonal Neoparamoeba perurans (NP), an AGD causative agent, in 35 ppt seawater containing 35 mM .OH radicals via one-off dosing for 1 hour at 15°C. In addition, fast radical consumption is more pronounced in the case of .OH radicals as compared to H2O2 in both freshwater and seawater due to extreme reactivity of the former. Hence, this study suggests that .OH radicals are detrimental to the viability of NP in seawater, and thereby, establishes grounds for further in vivo investigations of using seawater supplemented with continuous dosing of .OH radicals for Atlantic salmon bathing as a treatment of AGD

    Microbiological quality of raw milk attributable to prolonged refrigeration conditions

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    Refrigerated storage of raw milk is a prerequisite in dairy industry. However, temperature abused conditions in the farming and processing environments can significantly affect the microbiological quality of raw milk. Thus, the present study investigated the effect of different refrigeration conditions such as 2, 4, 6, 8, 10 and 12 °C on microbiological quality of raw milk from three different dairy farms with significantly different initial microbial counts. The bacterial counts (BC), protease activity (PA), proteolysis (PL) and microbial diversity in raw milk were determined during storage. The effect of combined heating (75 ± 0·5 °C for 15 s) and refrigeration on controlling those contaminating microorganisms was also investigated. Results of the present study indicated that all of the samples showed increasing BC, PA and PL as a function of temperature, time and initial BC with a significant increase in those criteria ≥6 °C. Similar trends in BC, PA and PL were observed during the extended storage of raw milk at 4 °C. Both PA and PL showed strong correlation with the psychrotrophic proteolytic count (PPrBC: at ≥4 °C) and thermoduric psychrotrophic count (TDPC: at ≥8 °C) compared to total plate count (TPC) and psychrotrophic bacterial count (PBC), that are often used as the industry standard. Significant increases in PA and PL were observed when PPrBC and TDPC reached 5 × 104cfu/ml and 1 × 104cfu/ml, and were defined as storage life for quality (SLQ), and storage life for safety (SLS) aspects, respectively. The storage conditions also significantly affected the microbial diversity, wherePseudomonas fluorescensandBacillus cereuswere found to be the most predominant isolates. However, deep cooling (2 °C) and combination of heating and refrigeration (≤4 °C) significantly extended theSLQandSLsof raw milk.</jats:p

    The influence of electromagnetic fields from two commercially available water-treatment devices on calcium carbonate precipitation

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    CaCO3 precipitation profiles, tracked by absorbance at 350 nm, showing accelerated precipitation upon exposure of the parent solutions to a pulsed electromagnetic field (PEMF) from a commercially available device.</p

    Shrinkage estimation for robust and efficient screening of single-SNP association from case-control genome-wide association studies

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    Population-based case-control design has become one of the most popular approaches for conducting genome-wide association scans for rare diseases like cancer. In this article, we propose a novel method for improving the power of the widely used single-single-nucleotide polymorphism (SNP) two-degrees-of-freedom (2 d.f.) association test for case-control studies by exploiting the common assumption of Hardy-Weinberg Equilibrium (HWE) for the underlying population. A key feature of the method is that it can relax the assumed model constraints via a completely data-adaptive shrinkage estimation approach so that the number of false-positive results due to the departure of HWE is controlled. The method is computationally simple and is easily scalable to association tests involving hundreds of thousands or millions of genetic markers. Simulation studies as well as an application involving data from a real genome-wide association study illustrate that the proposed method is very robust for large-scale association studies and can improve the power for detecting susceptibility SNPs with recessive effects, when compared to existing methods. Implications of the general estimation strategy beyond the simple 2 d.f. association test are discussed. Genet. Epidemiol . 33:740–750, 2009. Published 2009 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64559/1/20428_ftp.pd
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