Long-Run Equilibrium Modeling of Alternative Emissions Allowance Allocation Systems in Electric Power Markets

A question in the design of carbon dioxide trading systems is how allowances are to be initially allocated: by auction, by giving away fixed amounts, or by allocating based on output, fuel, or other decisions. The latter system can bias investment, operations, and pricing decisions, and increase costs relative to other systems. A nonlinear complementarity model is used to investigate long-run equilibria that would result under alternative systems for power markets characterized by time varying demand and multiple generation technologies. Existence of equilibria is shown under mild conditions. Solutions show that allocating allowances to new capacity based on fuel use or generator type can distort generation mixes, invert the operating order of power plants, and inflate consumer costs. The distortions can be smaller for tighter CO2 restrictions, and are somewhat mitigated if there are also electricity capacity markets or minimum-run restrictions on coal plants

Tipping Point

What happens to a woman at the tipping point under oppression in a patriarchal society? How does she behave? Pulling from the vagina dentata mythologies, and personal and collective experiences of rape culture, I formed a body of work which problematize the stereotypical narrative of victim/perpetrator. As a visual and conceptual exploration, my work explores the themes of desire, agency/non-agency, and violence [as it manifests within and outside of the body]. Utilizing visual and conceptual quotations from film, pornography and sex toys, these works subvert the exoticized stereotype of the Asian woman as sexual plaything

Distributed Optimal Frequency Control Considering a Nonlinear Network-Preserving Model

This paper addresses the distributed optimal frequency control of power systems considering a network-preserving model with nonlinear power flows and excitation voltage dynamics. Salient features of the proposed distributed control strategy are fourfold: i) nonlinearity is considered to cope with large disturbances; ii) only a part of generators are controllable; iii) no load measurement is required; iv) communication connectivity is required only for the controllable generators. To this end, benefiting from the concept of 'virtual load demand', we first design the distributed controller for the controllable generators by leveraging the primal-dual decomposition technique. We then propose a method to estimate the virtual load demand of each controllable generator based on local frequencies. We derive incremental passivity conditions for the uncontrollable generators. Finally, we prove that the closed-loop system is asymptotically stable and its equilibrium attains the optimal solution to the associated economic dispatch problem. Simulations, including small and large-disturbance scenarios, are carried on the New England system, demonstrating the effectiveness of our design

Overexpression of hypoxia-inducible factor prolylhydoxylase attenuated by HCG-induced vascular endothelial growth factor expression in luteal cells

Vascular endothelial growth factor (VEGF)-dependent angiogenesis plays a crucial role in the corpus leteum formation and their functional maintenances in mammalian ovaries. We recently reported that the activation of hypoxia-inducible factor (HIF)-1α signaling contributes to the regulation of VEGF expression in the luteal cells (LCs) in response to hypoxia and human chorionic gonadotropin (HCG). This study was designed to test the hypothesis that, HIF prolyl-dydoxylases (PHDs) express in LCs and overexpression of PHD attenuates the expression of VEGF induced by HCG in LCs. By real-time PCR and western blot analysis, we examined the expression of PHDs, confirmed the plasmid transfection and their expression and also investigated the changes of HIF-1α and VEGF expression after treatment with HCG and PHD2 transgenes. PHD2 expression was significantly higher than the others, indicating its main roles. Moreover, a significant increase of VEGF mRNA was found after HCG treatment, while this increased VEGF mRNA was also blocked by PHD2 overexpression in LCs. Further analysis also found that, this HCG-induced increase of VEGF mRNA was consistent with the level of HIF-1α protein, which is regulated by HIF prolyl-dydoxylase -mediated degradation. Taken together, our results indicated that, PHD2 mainly expressed in LCs and HCG-induced VEGF expression can be blocked by PHD2 overexpression through HIF-1α -mediated mechanism in LCs. This PHD2-mediated transcriptional activation may be one of the important mechanisms regulating VEGF expression in LCs during mammalian corpus leteum development.Key words: Hypoxia-inducible factor-1α, HIF prolyl-dydoxylase, vascular endothelial growth factor, human chorionic gonadotropin, luteal cells

Energy absorption by polymer crazing

During the past thirty years, a tremendous amount of research was done on the development of crazing in polymers. The phenomenon of crazing was recognized as an unusual deformation behavior associated with a process of molecular orientation in a solid to resist failure. The craze absorbs a fairly large amount of energy during the crazing process. When a craze does occur the surrounding bulk material is usually stretched to several hundred percent of its original dimension and creates a new phase. The total energy absorbed by a craze during the crazing process in creep was calculated analytically with the help of some experimental measurements. A comparison of the energy absorption by the new phase and that by the original bulk uncrazed medium is made

Feedback Control of Nuclear Spin Bath of a Single Hole Spin in a Quantum Dot

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Repeated doses of melatonin protects against focal cerebral ischemia in the rat

We studied the time window of neuroprotection against focal ischemia by a single dose or repeated doses of melatonin (MT) at 5 mg/kg. Adult male Sprague-Dawley rats (280 to 360 g) were anesthetized with sodium pentobarbital (60 mg/kg, I.P.) to undergo reversible right-sided endovascular middle cerebral artery occlusion (MCAO) for 3 hours. Arterial blood pressure, heart rate and cerebral blood flow were monitored, and rectal temperature was kept between 36.5 and 37.5 ºC throughout anesthesia. The control rats received 1 I.P. dose of the vehicle at the onset of ischemia, whereas experimental groups of rats received either 1 I.P. dose of MT at 0 or 60 minutes after onset of ischemia or 3 doses of MT at 1, 24, and 48 hours after onset of ischemia. The rats were decapitated on day 3 of MCAO, and their brains were stained with 2% triphenyltetrazolium chloride for determination of infarction. Results were compared using 2-tailed student’s t test. When compared to the relative infarct volume of 27.0±4.6% (mean±SEM; 7 rats) in the control group, a single (5 mg/kg) I.P. dose of MT did not significantly reduce the relative infarct volume (20.1±4.1% in the 0-minute group [8 rats]; 19.8±3.2% in the 60-minute group [9 rats]). Nevertheless, the relative infarct volume was significantly reduced to 13.9±3.4% (8 rats, P < 0.05) in the group which received 3 doses of MT. There was no significant difference in hemodynamic parameters among the groups. Thus, repeated doses rather than a single dose of exogenous MT protects against focal cerebral ischemia, when given 60 minutes after onset of ischemia. Supported by the CRCG Research Grant 10202138 of the University of Hong Kongpublished_or_final_versio