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This paper studies the optimal option purchase of a loss-averse retailer under emergent replenishment. It is assumed that all or part of the excess demands in a stock-out situation can be replenished, and the loss-averse retailer's optimal option purchase quantity is investigated. It is found that the loss-averse retailer should not purchase options and only needs to replenish the inventory under certain conditions. When maximizing the expected utility without shortage cost, the loss-averse retailer's optimal option purchase quantity is decreasing in the loss aversion coefficient. To maximise the expected utility with shortage cost, a larger shortage cost implies a bigger option purchase quantity. If the shortage cost exists, there will be a loss on the expected profit and utility for the loss-averse retailer who selects an optimal option purchase quantity without shortage cost. Given the optimal option purchase quantity, it is proven that the loss-averse retailer's expected profit is decreasing in the loss aversion coefficient. Therefore the retailer should choose a proper loss aversion preference to balance between the two objectives of profit maximization and loss aversion preference. As a result of these findings, some management insights are recommended to the loss-averse retailer in selecting the option purchase quantity. [ABSTRACT FROM AUTHOR]

Most current studies on the equilibrium decision-makings of a supply chain network (SCN) consider only completely rational retailers who always try to maximize their expected profits under the situations that demands are random. However, many evidences show that a retailer wants to choose the decision-making involving random demand which provides him with minimum regret. In this paper, we consider the impacts of retailers' anticipated regret aversion and experiential regret aversion on the equilibrium decision-makings of a random SCN with multiple production periods. Due to the random demand, the decision-makings of retailers are influenced not only by their anticipated regret, but also by their experiential regret after they have encountered bad or good experiences during past periods. The equilibrium conditions of the model are established. A numerical example is solved to illustrate the benefit of retailers obtained by considering their regret-averse behaviors. Moreover, it is found that retailers should consider their anticipated regret aversion or experiential regret aversion according to different situations of the demand markets. Correction: The third author's affiliation, previously "School of Computational and Applied Mathematics," is now called "School of Computer Science and Applied Mathematics." [ABSTRACT FROM AUTHOR]

Summary: In this paper, we use optimal parameter selection technique to develop two models involving single‐vendor–multiple‐buyer supply chain, which are called the dynamic independent optimization (DIO) model and the dynamic synchronized cycles (DSC) model, respectively. These models are, respectively, similar to the traditional static independent policy model and the traditional static synchronized cycle model, except that the deterministic demands of the buyers in the above two static models are now being replaced by the stochastic demands satisfying a Wiener process, which have more real‐life applications. Similar to the above static synchronized cycles model, the synchronization of the supply chain in our DSC model is also achieved by scheduling the delivery days of the buyers and coordinating them with the vendor's production cycle. Finding the optimal expected system costs of the DIO model and the DSC model involves solving optimal parameter selection problems governed by ordinary differential equations, whose final times are continuous decision variables and discrete decision variables, respectively. Computational methods have been developed for solving these problems. Numerical results show that the coordinated policy is better than the independent optimization policy, in terms of minimizing the expected system cost of the entire supply chain. Sensitivity analysis is performed to test the effect of changing the cost coefficients and the D¯/P value on the performances of these models, where D¯/P is the ratio of the total mean demand rate of all the buyers over the vendor's production rate. [ABSTRACT FROM AUTHOR]

This paper considers an optimal production scheduling problem in a single-supplier-multi-manufacturer supply chain involving production and delivery time-delays, where the time-delays for the supplier and the manufacturers can have different values. The objective of both levels is to find an optimal production schedule so that their production rates and their inventory levels are close to the ideal values as much as possible in the whole planning horizon. Each manufacturer's problem, which involves one time-delayed argument, can be solved analytically by using the necessary condition of optimality. To tackle the supplier's problem involving n + 1 different time-delayed arguments (where n is the number of manufacturers) by the above approach, we need to introduce a model transformation technique which converts the original system of combined algebraic/differential equations with n + 1 time-delayed arguments into a sum of n sub-systems, each of which consists of only two time-delayed arguments. Thus, the supplier's problem can also be solved analytically. Numerical examples consisting of a single supplier and four manufacturers are solved to provide insight of the optimal strategies of both levels. [ABSTRACT FROM AUTHOR]

To study the decision bias in newsvendor behavior, this paper introduces an opportunity loss minimization criterion into the newsvendor model with backordering. We apply the Conditional Value-at-Risk (CVaR) measure to hedge against the potential risks from newsvendor’s order decision. We obtain the optimal order quantities for a newsvendor to minimize the expected opportunity loss and CVaR of opportunity loss. It is proven that the newsvendor’s optimal order quantity is related to the density function of market demand when the newsvendor exhibits risk-averse preference, which is inconsistent with the results in Schweitzer and Cachon (2000). The numerical example shows that the optimal order quantity that minimizes CVaR of opportunity loss is bigger than expected profit maximization (EPM) order quantity for high-profit products and smaller than EPM order quantity for low-profit products, which is different from the experimental results in Schweitzer and Cachon (2000). A sensitivity analysis of changing the operation parameters of the two optimal order quantities is discussed. Our results confirm that high return implies high risk, while low risk comes with low return. Based on the results, some managerial insights are suggested for the risk management of the newsvendor model with backordering. [ABSTRACT FROM AUTHOR]

Recently, the first oligopolistic competition model of the closed-loop supply chain network involving uncertain demand and return has been established. This model belongs to the context of oligopolistic firms that compete noncooperatively in a Cournot-Nash framework. In this paper, we modify the above model in two different directions. (i) For each returned product from demand market to firm in the reverse logistics, we calculate the percentage of its optimal product flows in each individual path connecting the demand market to the firm. This modification provides the optimal product flow routings for each product in the supply chain and increases the optimal profit of each firm at the Cournot-Nash equilibrium. (ii) Our model extends the method of finding the Cournot-Nash equilibrium involving smooth objective functions to problems involving nondifferentiable objective functions. This modification caters for more real-life applications as a lot of supply chain problems involve nonsmooth functions. Existence of the Cournot-Nash equilibrium is established without the assumption of differentiability of the given functions. Intelligent algorithms, such as the particle swarm optimization algorithm and the genetic algorithm, are applied to find the Cournot-Nash equilibrium for such nonsmooth problems. Numerical examples are solved to illustrate the efficiency of these algorithms. [ABSTRACT FROM AUTHOR]

Genome shuffling was used to obtain Pachysolen tannophilus mutants with improved tolerance to inhibitors in hardwood spent sulfite liquor (HW SSL). Genome shuffled strains (GHW301, GHW302 and GHW303) grew at higher concentrations of HW SSL (80 % v/v) compared to the HW SSL UV mutant (70 % v/v) and the wild-type (WT) strain (50 % v/v). In defined media containing acetic acid (0.70-0.90 % w/v), GHW301, GHW302 and GHW303 exhibited a shorter lag compared to the acetic acid UV mutant, while the WT did not grow. Genome shuffled strains produced more ethanol than the WT at higher concentrations of HW SSL and an aspen hydrolysate. To identify the genetic basis of inhibitor tolerance, whole genome sequencing was carried out on GHW301, GHW302 and GHW303 and compared to the WT strain. Sixty single nucleotide variations were identified that were common to all three genome shuffled strains. Of these, 40 were in gene sequences and 20 were within 5 bp-1 kb either up or downstream of protein encoding genes. Based on the mutated gene products, mutations were grouped into functional categories and affected a variety of cellular functions, demonstrating the complexity of inhibitor tolerance in yeast. Sequence analysis of UV mutants (UAA302 and UHW303) from which GHW301, GHW302 and GHW303 were derived, confirmed the success of our cross-mating based genome shuffling strategy. Whole-genome sequencing analysis allowed identification of potential gene targets for tolerance to inhibitors in lignocellulosic hydrolysates. [ABSTRACT FROM AUTHOR]

Background: The zebrafish genetic mutant iguana ( igu) has defects in the ciliary basal body protein Dzip1, causing improper cilia formation. Dzip1 also interacts with the downstream transcriptional activators of Hedgehog (Hh), the Gli proteins, and Hh signaling is disrupted in igu mutants. Hh governs a wide range of developmental processes, including stabilizing developing blood vessels to prevent hemorrhage. Using igu mutant embryos and embryos treated with the Hh pathway antagonist cyclopamine, we conducted a microarray to determine genes involved in Hh signaling mediating vascular stability. Results: We identified 40 genes with significantly altered expression in both igu mutants and cyclopamine-treated embryos. For a subset of these, we used in situ hybridization to determine localization during embryonic development and confirm the expression changes seen on the array. Conclusions: Through comparing gene expression changes in a genetic model of vascular instability with a chemical inhibition of Hh signaling, we identified a set of 40 differentially expressed genes with potential roles in vascular stabilization. Developmental Dynamics 244:211-223, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Global gene expression was analyzed in Saccharomyces cerevisiae T2 cells grown in the presence of hardwood spent sulphite liquor (HW SSL) and each of the three main inhibitors in HW SSL, acetic acid, hydroxymethyfurfural (HMF) and furfural, using a S. cerevisiae DNA oligonucleotide microarray. The objective was to compare the gene expression profiles of T2 cells in response to the individual inhibitors against that elicited in response to HW SSL. Acetic acid mainly affected the expression of genes related to the uptake systems of the yeast as well as energy generation and metabolism. Furfural and HMF mainly affected the transcription of genes involved in the redox balance of the cell. On the other hand, the effect of HW SSL on S. cerevisiae T2 cells was distinct and considerably more diverse as compared to the effect of individual inhibitors found in lignocellulosic hydrolysates. This is not surprising as HW SSL contains a complex mixture of inhibitors which may act synergistically. HW SSL elicited significant changes in expression of genes involved in diverse and multiple effects on several aspects of the cellular structure and function. A notable response to HW SSL was decreased expression of the ribosomal protein genes in T2 cells. In addition, HW SSL decreased the expression of genes functioning in the synthesis and transport of proteins as well as metabolism of carbohydrates, lipids, vitamins and vacuolar proteins. Furthermore, the expression of genes involved in multidrug resistance, iron transport and pheromone response was increased, suggesting that T2 cells grown in the presence of HW SSL may have activated pheromone response and/or activated pleiotropic drug response. Some of the largest changes in gene expression were observed in the presence of HW SSL and the affected genes are involved in mating, iron transport, stress response and phospholipid metabolism. A total of 59 out of the 400 genes differentially expressed in the presence of HW SSL, acetic acid, HMF and furfural, belonged to the category of poorly characterized genes. The results indicate that transcriptional responses to individual lignocellulosic inhibitors gave a different picture and may not be representative of how the cells would respond to the presence of all the inhibitors in lignocellulosic hydrolysates such as HW SSL. [ABSTRACT FROM AUTHOR]

viscosity method for a hierarchical fixed point solving variational inequality problems is presented. The method is used to solve variational inequalities, where the involved mappings are non-expansive. Solutions are sought in the set of the fixed points of another non-expansive mapping. As applications, we use the results to study problems of the monotone variational inequality, the convex programming, the hierarchical minimization, and the quadratic minimization over fixed point sets. [ABSTRACT FROM AUTHOR]

This paper proposes a modified iterative algorithm using a viscosity approximation method with a weak contraction. The purpose is to find a common element of the set of common fixed points of an infinite family of nonexpansive mappings and the set of a finite family of equilibrium problems that is also a solution to a variational inequality. Under suitable conditions, some strong convergence theorems are established in the framework of Hilbert spaces. The results presented in the paper improve and extend the corresponding results of Colao et al. (Colao, V., Acedo, G. L., and Marino, G. An implicit method for finding common solutions of variational inequalities and systems of equilibrium problems and fixed points of infinite family of nonexpansive mappings. Nonlinear Anal. 71, 2708-2715 (2009)), Plubtieng and Punpaeng (Plubtieng, S. and Punpaeng, R. A general iterative method for equilibrium problems and fixed point problems in Hilbert spaces. J. Math. Anal. Appl. 336, 455-469 (2007)), Colao et al. (Colao, V., Marino, G., and Xu, H. K. An iterative method for finding common solutions of equilibrium problem and fixed point problems. J. Math. Anal. Appl. 344, 340-352 (2008)), Yao et al. (Yao, Y., Liou, Y. C., and Yao, J. C. Convergence theorem for equilibrium problems and fixed point problems of infinite family of nonexpansive mappings. Fixed Point Theory Application 2007, Article ID 64363 (2007) DOI 10.1155/2007/64363), and others. [ABSTRACT FROM AUTHOR]

Efficacy of CRT for Mildly Prolonged QRS.. Introduction:Cardiac resynchronization therapy (CRT) has been shown to reverse left ventricular (LV) remodeling and improve symptoms in heart failure patients with wide QRS complexes; however, its role in patients with mildly prolonged QRS complexes is unclear. This study investigated if CRT benefited patients with mildly prolonged QRS complexes>120 to 150 ms and explored if the severity of systolic asynchrony determined such a response.Methods and Results:Fifty-eight patients (age 66± 11 years, 66% male) who had undergone CRT were studied prospectively. Of these patients, 27 had QRS duration between 120 and 150 ms (group A), and 31 had QRS duration>150 ms (group B). Tissue Doppler echocardiography and clinical assessment were performed at baseline and 3 months after CRT. Both groups had significant reduction of LV volume and increased ejection fraction,+dP/dt, and sphericity index (all P<0.05). These improvements were greater in group B and were explained by the higher prevalence of systolic intraventricular asynchrony. Significant reverse remodeling (reduction of LV end-systolic volume>15%) was evident in 46% of group A patients and 68% of group B patients. Improvement in clinical endpoints was observed in both groups (all P<0.01), although the changes in metabolic equivalent and New York Heart Association functional class were greater in group B. In both groups, systolic asynchrony index (TS-SD) was the most important predictor of reverse remodeling (r=−0.78, P<0.001) and was the only independent predictor in the multivariate model (β=−1.80, confidence interval=−2.18 to−1.42, P<0.001); QRS duration was not. A predefined TS-SD value>32.6 ms had a sensitivity of 94% and specificity of 83% to predict reverse remodeling. Improvement of intraventricular asynchrony after CRT was evident only in responders (P= 0.01).Conclusion:Improvement of LV remodeling and clinical status is evident after CRT in heart failure patients with QRS duration>120 to 150 ms. These responders are closely predicted by the severity of prepacing intraventricular asynchrony but not QRS duration.(J Cardiovasc Electrophysiol, Vol. 15, pp. 1-8, September 2004) [ABSTRACT FROM AUTHOR]

As an initial step to implement total quality management (TQM) in a small manufacturing enterprise (SME) of electrical products, we applied statistical techniques to quantify and evaluate the data collected in order to improve the quality characteristics of a selected product circuit breaker. A circuit breaker will “jump” or the current will be cut short if a current stronger than 15A passes through the equipment. The time required for the circuit breaker to stop the flow of the current is called the trip-time. Our major concern is to find out how sensitive a 15A circuit breaker is, and how reliable is the device. We were able to confirm several dominant factors that influence the trip-time of the circuit breaker after conducting several experiments. We used regression analysis to find out the model that best fits the relationship between the current supply and the trip-time of the 15A circuit breaker. Meanwhile reliability testings of the circuit breaker were performed. Balanced factorial design techniques were applied in finding out the optimal combination of factors with the highest success rate of trips. The results demonstrated that the optimal combination of factors we found could bring about quality improvement of the product. [ABSTRACT FROM AUTHOR]

Studies protein folding kinetics with the extrinsic ligand imidazole bound to the heme. Equilibrium unfolding curve; Biphasic nature of the fluorescence decrease; Barrier-free, partial collapse of the equilibrium unfolded state; Dynamics of collapse and barrier crossings in protein folding.

Introduction. Sibutramine is an amphetamine-like drug used for its weight reducing effect. Sibutramine-induced acute coronary syndrome has rarely been reported. We report a case of myocardial infarction associated with the use of sibutramine. Case Report. A 37-year-old woman presented to an Emergency Department (ED) with intermittent retrosternal chest pain, nausea, and sweating for 3 days. She reported taking one sibutramine tablet each day for 3 days. Blood pressure was 128/89 mm Hg and pulse 66 beats/min. An electrocardiogram revealed ST elevation over the inferior leads and ST depression over leads AVR and V1, the other leads were normal. Serum troponin T was 0.65 μg/L, and sibutramine was identified in her urine. Echocardiography revealed mild hypokinesia over the inferior wall without evidence of acute aortic dissection. The ST segment changes resolved spontaneously within 24 h of cardiac care unit (CCU) admission, a coronary angiogram performed 1 week later was unremarkable, and echocardiography performed 4 weeks after the event showed normal resting regional wall motion. Discussion. Seventeen medications containing sibutramine as an active ingredient were registered in Hong Kong in 2007. Sibutramine was introduced in the United States in 1997 and in Australia, United Kingdom, and Italy in 2001. Hypertension, tachycardia, dry mouth, and headache are the most commonly reported adverse reactions. Cardiovascular toxicities include tachycardia, palpitation, hypertension, and tachyarrhythmia. Conclusions. We postulate that the myocardial infarction was the result of coronary vasospasm associated with the therapeutic use of sibutramine-containing slimming pills. [ABSTRACT FROM AUTHOR]