391 research outputs found
Optimal bank portfolio choice under fixed-rate deposit insurance
An analysis of the investment decisions of a bank whose deposits are fully insured under fixed-rate insurance, showing how banks dynamically adjust their investment portfolios in response to market information and how this flexibility affects both investment decisions and the fair cost of deposit insurance.Deposit insurance ; Bank investments
Regulatory taxes, investment, and financing decision for insured banks
An investigation of the effects of interest rate and credit risk on optimal capital structure and investment decisions. The authors show that with no uncertainty in interest rates, capital regulation will reduce the risk of the bank's assets, but that under interest rate uncertainty, the impact of regulation may be detrimental and raise the risk of the deposits as well as government subsidies to the bank's shareholders.Bank capital ; Deposit insurance
On flexibility, capital structure, and investment decisions for the insured bank
Most models of deposit insurance assume that the volatility of a bank's assets is exogenously provided. Although this framework allows the impact of volatility on bankruptcy costs and deposit insurance subsidies to be explored, it is static and does not incorporate the fact that equityholders can respond to market events by adjusting previous investment and leverage decisions. This paper presents a dynamic model of a bank that allows for such behavior. The flexibility of being able to respond dynamically to market information has value to equityholders. The impact and value of this flexibility option are explored under a regime in which flat-rate deposit insurance is provided.Deposit insurance ; Bank capital
Binomial approximation in financial models: computational simplicity and convergence
An exploration of the potential of transformation and other schemes in approximating diffusions (including those with boundaries) commonly seen in financial models. Convergence results are established for valuing both European and American contingent claims.Statistics
Functional characterization of a novel KCNJ11 in frame mutation-deletion associated with infancy-onset diabetes and a mild form of intermediate DEND: A battle between K(ATP) gain of channel activity and loss of channel expression
ATP-sensitive potassium (K(ATP)) channels are widely distributed in various tissues and cell types where they couple cell metabolism to cell excitability. Gain of channel function (GOF) mutations in the genes encoding Kir6.2 (KCNJ11) or the associated regulatory ssulfonylurea receptor 1 subunit (ABCC8), cause developmental delay, epilepsy and neonatal diabetes (DEND) due to suppressed cell excitability in pancreatic β-cells and neurons. The objective of this study was to determine the molecular basis of infancy-onset diabetes and a mild form of intermediate DEND, resulting from a novel KCNJ11 in frame mutation plus deletion. The naturally occurring Kir6.2 mutation plus deletion (Ser225Thr, Pro226_Pro232del) as well as the isolated S225T mutation or isolated del226–232 deletion were coexpressed with SUR1 in COS cells in homozygous or heterozygous states. The protein expression and gating effects of the resulting channels were assessed biochemically and electrophysiologically. For both the deletion and point mutations, simulated heterozygous expression resulted in overall increased conductance in intact cells in basal conditions and rightward shifted ATP dose-response curves in excised patches, due to increased intrinsic open probability. Interestingly, homomeric channels for the combined deletion/mutation, or for the deletion alone, showed dramatically reduced channel expression at the cell membrane, which would underlie a reduced function in vivo. These results demonstrate that both the mis-sense mutation and the deleted region in the Kir6.2 subunit are important for control of the intrinsic channel gating and suggest that the clinical presentation could be affected by the competition between loss-of-function by reduced trafficking and enhanced channel gating
Some Observations on the Optimal Material Removal Rate in Unreliable Metal Cutting Processes
This paper examines the foundation for economic analysis in unreliable metal cutting processes. We present some results on the machining parameter optimization problem, explaining the effect of the cutting speed on tool life and the rate of acceptance. [Published circa 1985-1988.
Machining Parameter Selection for a Stochastic Flow System
This paper examines the foundation for economic analysis in unreliable metal cutting processes. Using queuing models, we present some observations on the effect of cutting speed upon tool life, rate of acceptance of work, and mean flow time in machining parameter optimization. [Published circa 1987-1989.
Hypotension due to Kir6.1 gain‐of‐function in vascular smooth muscle
BACKGROUND: K(ATP) channels, assembled from pore‐forming (Kir6.1 or Kir6.2) and regulatory (SUR1 or SUR2) subunits, link metabolism to excitability. Loss of Kir6.2 results in hypoglycemia and hyperinsulinemia, whereas loss of Kir6.1 causes Prinzmetal angina–like symptoms in mice. Conversely, overactivity of Kir6.2 induces neonatal diabetes in mice and humans, but consequences of Kir6.1 overactivity are unknown. METHODS AND RESULTS: We generated transgenic mice expressing wild‐type (WT), ATP‐insensitive Kir6.1 [Gly343Asp] (GD), and ATP‐insensitive Kir6.1 [Gly343Asp,Gln53Arg] (GD‐QR) subunits, under Cre‐recombinase control. Expression was induced in smooth muscle cells by crossing with smooth muscle myosin heavy chain promoter–driven tamoxifen‐inducible Cre‐recombinase (SMMHC‐Cre‐ER) mice. Three weeks after tamoxifen induction, we assessed blood pressure in anesthetized and conscious animals, as well as contractility of mesenteric artery smooth muscle and K(ATP) currents in isolated mesenteric artery myocytes. Both systolic and diastolic blood pressures were significantly reduced in GD and GD‐QR mice but normal in mice expressing the WT transgene and elevated in Kir6.1 knockout mice as well as in mice expressing dominant‐negative Kir6.1 [AAA] in smooth muscle. Contractile response of isolated GD‐QR mesenteric arteries was blunted relative to WT controls, but nitroprusside relaxation was unaffected. Basal K(ATP) conductance and pinacidil‐activated conductance were elevated in GD but not in WT myocytes. CONCLUSIONS: K(ATP) overactivity in vascular muscle can lead directly to reduced vascular contractility and lower blood pressure. We predict that gain of vascular K(ATP) function in humans would lead to a chronic vasodilatory phenotype, as indeed has recently been demonstrated in Cantu syndrome
Effect of Paclitaxel+Hirudin on the TLR4-MyD88 Signaling Pathway During Inflammatory Activation of Human Coronary Artery Smooth Muscle Cells and Mechanistic Analysis
Background/Aims: Approximately 10%-20% of patients with acute cardiovascular disease who have received coronary intervention suffer restenosis and high inflammation. The stent compound paclitaxel+hirudin was prepared for the treatment of post-intervention restenosis. This study aimed to explore the anti-inflammatory and anti-restenosis mechanisms of paclitaxel+hirudin with regard to the TLR4/MyD88/NF-κB pathway. Methods: Human coronary artery smooth muscle cells (HCASMCs) at 4-6 generations after in vitro culture were used as a model. Lipopolysaccharide (LPS) was used as an inducer to maximally activate the TLR4/MyD88/NF-κB inflammation pathway. After MyD88 knockdown and selective blocking of MyD88 degradation with epoxomicin, the effects of paclitaxel+hirudin stenting on key sites of the TLR4/MyD88/NF-κB pathway were detected using ELISA, Q-PCR, and western blot analysis. Results: LPS at 1 μg/mL for 48 h was the optimal modeling condition for inflammatory activation of HCASMCs. Paclitaxel+hirudin inhibited the levels of key proteins and the gene expression, except for that of the MyD88 gene, of the TLR4-MyD88 pathway. The trend of the effect of paclitaxel+hirudin on the pathway proteins was similar to that of MyD88 knockdown. After epoxomicin intervention, the inhibitory effects of paclitaxel+hirudin on the key genes and proteins of the TLR4-MyD88 pathway were significantly weakened, which even reached pre-intervention levels. Paclitaxel+hirudin affected the MyD88 protein in a dosage-dependent manner. Conclusion: The paclitaxel+hirudin compound promotes MyD88 degradation in the TLR4/MyD88/NF-κB pathway to reduce the activity of TLR4 and NF-κB p65 and to weaken the LPS-initiated inflammatory reactions of IL-1β, IL-6, and TNF-α
DDNet: Dual-path Decoder Network for Occlusion Relationship Reasoning
Occlusion relationship reasoning based on convolution neural networks
consists of two subtasks: occlusion boundary extraction and occlusion
orientation inference. Due to the essential differences between the two
subtasks in the feature expression at the higher and lower stages, it is
challenging to carry on them simultaneously in one network. To address this
issue, we propose a novel Dual-path Decoder Network, which uniformly extracts
occlusion information at higher stages and separates into two paths to recover
boundary and occlusion orientation respectively in lower stages. Besides,
considering the restriction of occlusion orientation presentation to occlusion
orientation learning, we design a new orthogonal representation for occlusion
orientation and proposed the Orthogonal Orientation Regression loss which can
get rid of the unfitness between occlusion representation and learning and
further prompt the occlusion orientation learning. Finally, we apply a
multi-scale loss together with our proposed orientation regression loss to
guide the boundary and orientation path learning respectively. Experiments
demonstrate that our proposed method achieves state-of-the-art results on PIOD
and BSDS ownership datasets
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