Investors’ Greed and Fear: An Event Study of Analyst Recommendations

We investigate the effect of the skewness developed by the CBOE, called SKEW, on investors’ reactions to analyst recommendations. Our results show that the abnormal stock returns around analyst recommendation revisions are closely correlated with contemporaneous SKEW changes. Specifically, positive (negative) abnormal returns following analyst recommendation upgrades (downgrades) are stronger when daily SKEW increases (decreases). A potential explanation for this relation is that SKEW captures investors’ greed (excitement) in the stock market. Similar to the CBOE VIX, SKEW might act as another measure to reflect investors’ moods or sentiments. However, in contrast to VIX, which is usually used as investors’ fear gauge, SKEW is the opposite of investors’ fear, measuring investors’ consensus view of future positive news. Furthermore, we show that the magnitudes of abnormal returns associated with the change in SKEW are larger for the NASDAQ than for the NYSE on recommendation announcement days. This may manifest the different types of firms listed on these two stock exchanges

Effect of blocking Ras signaling pathway with K-Ras siRNA on apoptosis in esophageal squamous carcinoma cells

AbstractObjectiveTo study the effect of RNAi silencing of the K-Ras gene on Ras signal pathway activity in EC9706 esophageal cancer cells.MethodsEC9706 cells were treated in the following six groups: blank group (no transfection), negative control group (transfection no-carrier), transfection group (transfected with pSilencer-siK-ras), taxol chemotherapy group, taxol chemotherapy plus no-carrier group, taxol chemotherapy plus transfection group. Immunocytochemistry, Reverse transcription-polymerase chain reaction and western blotting were used to analyze the expression of MAPK1 (mitogen-activated protein kinases 1) and cyclin D1 in response to siRNA (small interfering RNA) transfection and taxol treatment.ResultsK-Ras (K-Ras gene) siRNA transfection of EC9706 esophageal squamous carcinoma cells decreased the expression of K-Ras, MAPK1 and cyclin D1 at the mRNA and protein level. Reverse transcription-polymerase chain reaction indicated that the expression levels of MAPK1 and cyclin D1 mRNAs were significantly lower in the transfection group than in the blank group (P<0.05). Western blotting showed that 72 h after EC9706 cell transfection, the expression levels of MAPK1 and cyclin D1 proteins had decreased in all groups, and the expression levels in the transfection group were significantly inhibited as compared with the blank group. Apoptosis increased significantly in the transfection group or after addition of taxol as compared with the blank group and the no-carrier group. The degree of apoptosis in the taxol plus transfection group was more severe.ConclusionApoptosis increased significantly in EC9706 esophageal carcinoma cells after siRNA-mediated inhibition of Ras signaling, with the most obvious increase observed in the transfection plus taxol chemotherapy group. Ras knockdown therefore increased cellular sensitivity to the chemotherapeutic agent, taxol. Ras knockdown also down-regulated the expression of the downstream genes, MAPK1 and cyclin D1, thus inhibiting the growth, proliferation and metabolism of esophageal cancer cells

2,2′-Bis(prop-2-yn­yloxy)-1,1′-binaphth­yl

In the title compound, C26H18O2, the mol­ecule is located on a twofold rotation axis. The two naphthyl ring planes in the mol­ecule are nearly perpendicular to each other [dihedral angle = 82.42 (1)°. No classical hydrogen bonds or aromatic π–π stacking inter­actions were observed

A Note on the Rate of Strong Convergence for Weighted Sums of Arrays of Rowwise Negatively Orthant Dependent Random Variables

Let {Xni;i≥1,n≥1} be an array of rowwise negatively orthant dependent (NOD) random variables. The authors discuss the rate of strong convergence for weighted sums of arrays of rowwise NOD random variables and solve an open problem posed by Huang and Wang (2012)

Pharmacological Basis for Use of Armillaria mellea

Armillaria mellea, an edible fungus, exhibits various pharmacological activities, including antioxidant and antiapoptotic properties. However, the effects of A. mellea on Alzheimer’s disease (AD) have not been systemically reported. The present study aimed to explore the protective effects of mycelium polysaccharides (AMPS) obtained from A. mellea, especially AMPSc via 70% ethanol precipitation in a L-glutamic acid- (L-Glu-) induced HT22 cell apoptosis model and an AlCl3 plus D-galactose- (D-gal-) induced AD mouse model. AMPSc significantly enhanced cell viability, suppressed nuclear apoptosis, inhibited intracellular reactive oxygen species accumulation, prevented caspase-3 activation, and restored mitochondrial membrane potential (MMP). In AD mice, AMPSc enhanced horizontal movements in an autonomic activity test, improved endurance times in a rotarod test, and decreased escape latency time in a water maze test. Furthermore, AMPSc reduced the apoptosis rate, amyloid beta (Aβ) deposition, oxidative damage, and p-Tau aggregations in the AD mouse hippocampus. The central cholinergic system functions in AD mice improved after a 4-week course of AMPSc administration, as indicated by enhanced acetylcholine (Ach) and choline acetyltransferase (ChAT) concentrations, and reduced acetylcholine esterase (AchE) levels in serum and hypothalamus. Our findings provide experimental evidence suggesting A. mellea as a neuroprotective candidate for treating or preventing neurodegenerative diseases

Examination of optimizing information flow in networks

The central role of the Internet and the World-Wide-Web in global communications has refocused much attention on problems involving optimizing information flow through networks. The most basic formulation of the question is called the "max flow" optimization problem: given a set of channels with prescribed capacities that connect a set of nodes in a network, how should the materials or information be distributed among the various routes to maximize the total flow rate from the source to the destination. Theory in linear programming has been well developed to solve the classic max flow problem. Modern contexts have demanded the examination of more complicated variations of the max flow problem to take new factors or constraints into consideration; these changes lead to more difficult problems where linear programming is insufficient. In the workshop we examined models for information flow on networks that considered trade-offs between the overall network utility (or flow rate) and path diversity to ensure balanced usage of all parts of the network (and to ensure stability and robustness against local disruptions in parts of the network). While the linear programming solution of the basic max flow problem cannot handle the current problem, the approaches primal/dual formulation for describing the constrained optimization problem can be applied to the current generation of problems, called network utility maximization (NUM) problems. In particular, primal/dual formulations have been used extensively in studies of such networks. A key feature of the traffic-routing model we are considering is its formulation as an economic system, governed by principles of supply and demand. Considering channel capacities as a commodity of limited supply, we might suspect that a system that regulates traffic via a pricing scheme would assign prices to channels in a manner inversely proportional to their respective capacities. Once an appropriate network optimization problem has been formulated, it remains to solve the optimization problem; this will need to be done numerically, but the process can greatly benefit from simplifications and reductions that follow from analysis of the problem. Ideally the form of the numerical solution scheme can give insight on the design of a distributed algorithm for a Transmission Control Protocol (TCP) that can be directly implemented on the network. At the workshop we considered the optimization problems for two small prototype network topologies: the two-link network and the diamond network. These examples are small enough to be tractable during the workshop, but retain some of the key features relevant to larger networks (competing routes with different capacities from the source to the destination, and routes with overlapping channels, respectively). We have studied a gradient descent method for solving obtaining the optimal solution via the dual problem. The numerical method was implemented in MATLAB and further analysis of the dual problem and properties of the gradient method were carried out. Another thrust of the group's work was in direct simulations of information flow in these small networks via Monte Carlo simulations as a means of directly testing the efficiencies of various allocation strategies

An extract of Artemisia dracunculus L. stimulates insulin secretion from β cells, activates AMPK and suppresses inflammation

© 2015 Elsevier Ireland Ltd. All rights reserved. Ethnopharmacological relevance Artemisia dracunculus L. (Russian tarragon) is a perennial herb belonging to the family Compositae and has a history of medicinal use in humans, particularly for treatment of diabetes. Aim of the study: In this study a defined plant extract from A. dracunculus L. (termed PMI-5011) is used to improve beta(β) cells function and maintain β cell number in pancreatic islets as an alternative drug approach for successful treatment of diabetes. Materials and methods Mouse and human pancreatic beta cells were treated with defined plant extract of A. dracunculus L. (PMI-5011) to understand the mechanism(s) that influence beta cell function and β cell number. Results We found that the PMI-5011 enhances insulin release from primary β cells, isolated mouse and human islets and it maintains β cell number. Insulin released by PMI-5011 is associated with the activation of AMP-activated protein kinase (AMPK), and protein kinase B (PKB). Furthermore, PMI-5011 suppresses LPS/INFγ-induced inflammation and inflammatory mediator(s) in macrophages. PMI-5011 inhibited Nitric oxide (NO) production and expression of inducible nitric oxide synthase (iNOS) at the protein level and also attenuated pro-inflammatory cytokine (IL-6) production in macrophages. Conclusion PMI-5011 has potential therapeutic value for diabetes treatment via increasing insulin release from β cells and decreases capacity of macrophages to combat inflammation