Embryonic stem cell-specific signatures in cancer: insights into genomic regulatory networks and implications for medicine

Embryonic stem (ES) cells are of great interest as a model system for studying early developmental processes and because of their potential therapeutic applications in regenerative medicine. Obtaining a systematic understanding of the mechanisms that control the 'stemness' - self-renewal and pluripotency - of ES cells relies on high-throughput tools to define gene expression and regulatory networks at the genome level. Such recently developed systems biology approaches have revealed highly interconnected networks in which multiple regulatory factors act in combination. Interestingly, stem cells and cancer cells share some properties, notably self-renewal and a block in differentiation. Recently, several groups reported that expression signatures that are specific to ES cells are also found in many human cancers and in mouse cancer models, suggesting that these shared features might inform new approaches for cancer therapy. Here, we briefly summarize the key transcriptional regulators that contribute to the pluripotency of ES cells, the factors that account for the common gene expression patterns of ES and cancer cells, and the implications of these observations for future clinical applications.Institute for Cellular and Molecular [email protected]

Electrical Control of Silicon Photonic Crystal Cavity by Graphene

Efficient conversion of electrical signal to optical signal in nano-photonics enables solid state integration of electronics and photonics. Combination of graphene with photonic crystals is promising for electro-optic modulation. In this paper, we demonstrate that by electrostatic gating a single layer of graphene on top of a photonic crystal cavity, the cavity resonance can be changed significantly. A ~2nm change in the cavity resonance linewidth and almost 400% (6 dB) change in resonance reflectivity is observed. In addition, our analysis shows that a graphene-photonic crystal device can potentially be useful for a high speed, and low power absorptive and refractive modulator, while maintaining a small physical footprint.Comment: 4 figure

Embryonic stem cell-specific signatures in cancer: insights into genomic regulatory networks and implications for medicine

Embryonic stem (ES) cells are of great interest as a model system for studying early developmental processes and because of their potential therapeutic applications in regenerative medicine. Obtaining a systematic understanding of the mechanisms that control the 'stemness' - self-renewal and pluripotency - of ES cells relies on high-throughput tools to define gene expression and regulatory networks at the genome level. Such recently developed systems biology approaches have revealed highly interconnected networks in which multiple regulatory factors act in combination. Interestingly, stem cells and cancer cells share some properties, notably self-renewal and a block in differentiation. Recently, several groups reported that expression signatures that are specific to ES cells are also found in many human cancers and in mouse cancer models, suggesting that these shared features might inform new approaches for cancer therapy. Here, we briefly summarize the key transcriptional regulators that contribute to the pluripotency of ES cells, the factors that account for the common gene expression patterns of ES and cancer cells, and the implications of these observations for future clinical applications

Non-Einstein Viscosity Phenomenon of Acrylonitrile–Butadiene–Styrene Composites Containing Lignin–Polycaprolactone Particulates Highly Dispersed by High-Shear Stress

Lignin powder was modified via ring-opening polymerization of caprolactone to form a lignin–polycaprolactone (LPCL) particulate. The LPCL particulates were mixed with an acrylonitrile–butadiene–styrene (ABS) matrix at an extremely high rotational speed of up to 3000 rpm, which was achieved by a closed-loop screw mixer and in-line melt extruder. Using this high-shear extruding mixer, the LPCL particulate size was controlled in the range of 3395 nm (conventional twin-screw extrusion) down to 638 nm (high-shear mixer of 3000 rpm) by altering the mixing speed and time. The resulting LPCL/ABS composites clearly showed non-Einstein viscosity phenomena, exhibiting reduced viscosity (2130 Pa·s) compared to the general extruded composite one (4270 Pa·s) at 1 s–1 and 210 °C. This is due to the conformational rearrangement and the increased free volume of ABS molecular chains in the vicinity of LPCL particulates. This was supported by the decreased glass transition temperature (Tg, 83.7 °C) of the LPCL/ABS composite specimens, for example, giving a 21.8% decrement compared to that (107 °C) of the neat ABS by the incorporation of 10 wt % LPCL particulates in ABS. The LPCL particulate morphology, damping characteristics, and light transmittance of the developed composites were thoroughly investigated at various levels of applied shear rates and mixing conditions. The non-Einstein rheological phenomena stemming from the incorporation of LPCL particulates suggest an interesting plasticization methodology: to improve the processability of high-loading filler/polymer composites and ultra-high molecular weight polymers that are difficult to process because of their high viscosity

Politician’s Equity Holdings and Corporate Social Responsibility

This study examines the relationship between politician’s equity holdings and the corporate social responsibility (CSR) performance of companies. Politician equity holdings reflect not only the self-interested investment activity of firms, but also a potential source of benefit to the firm as politicians naturally pursue their self-interest through pro-firm legislative and regulatory activity. These investments come at the cost, however, of increased public scrutiny and political monitoring over the firm’s activities. Using politician equity holding data and CSR data for a sample of S&P 1500 firms, we find evidence that firms respond to politician equity holdings through both increased CSR strengths and concerns, suggesting that both social pressure and politician interventions are motivating firm CSR behavior. These findings are robust to the use of alternative models which account for potential endogeneity concerns

Tgif1 Counterbalances The Activity Of Core Pluripotency Factors In Mouse Embryonic Stem Cells

Core pluripotency factors, such as Oct4, Sox2, and Nanog, play important roles in maintaining embryonic stem cell (ESC) identity by autoregulatory feedforward loops. Nevertheless, the mechanism that provides precise control of the levels of the ESC core factors without indefinite amplification has remained elusive. Here, we report the direct repression of core pluripotency factors by Tgif1, a previously known terminal repressor of TGF beta/activin/nodal signaling. Overexpression of Tgif1 reduces the levels of ESC core factors, whereas its depletion leads to the induction of the pluripotency factors. We confirm the existence of physical associations between Tgif1 and Oct4, Nanog, and HDAC1/2 and further show the level of Tgif1 is not significantly altered by treatment with an activator/inhibitor of the TGF beta/activin/nodal signaling. Collectively, our findings establish Tgif1 as an integral member of the core regulatory circuitry of mouse ESCs that counterbalances the levels of the core pluripotency factors in a TGF beta/activin/nodal-independent manner.Cancer Prevention Research Institute of Texas (CPRIT) R1106Molecular Bioscience

Combat effectiveness and efficiency evaluation of firearm weapon systems in different projectile guidance simulations

We analyze the combat effectiveness and efficiency of the firearm weapon systems with stochastic simulations approach. Such combat effectiveness and efficiency are related with the precision of weapon systems, but the precision varies greatly depending on the projectile guidance method of the weapon system. Thus, this study conducted a stochastic simulation based on a mathematical model considering different projectile guidance methods. The simulation was designed assuming Counter-Artillery Fire, which is an important battle that must be successful in order to achieve a firepower advantage in the early stages of the war, and is suitable for judging the combat effectiveness and efficiency due to the precision of the firearm weapons system. Combat effectiveness and efficiency are judged as the result of damage probability, damage type, and desired shooting frequency, and damage probability and damage type represent combat effectiveness, and desired shooting frequency represents efficiency. The simulation environment deployed and simulated an enemy artillery unit with a size of 1,000m × 750m in the target area (6 guns), and applied the killing range of each firearm weapon system. For the description of the damage, the mathematical models Carlton damage function and the cookie cutter damage function were applied, and Monte Carlo simulation was applied to simulate the uncertainty of the battlefield. The results of the present study can be provided basic data to effectively operate and plan the firearm weapon systems

Combat effectiveness and efficiency evaluation of firearm weapon systems in different projectile guidance simulations

We analyze the combat effectiveness and efficiency of the firearm weapon systems with stochastic simulations approach. Such combat effectiveness and efficiency are related with the precision of weapon systems, but the precision varies greatly depending on the projectile guidance method of the weapon system. Thus, this study conducted a stochastic simulation based on a mathematical model considering different projectile guidance methods. The simulation was designed assuming Counter-Artillery Fire, which is an important battle that must be successful in order to achieve a firepower advantage in the early stages of the war, and is suitable for judging the combat effectiveness and efficiency due to the precision of the firearm weapons system. Combat effectiveness and efficiency are judged as the result of damage probability, damage type, and desired shooting frequency, and damage probability and damage type represent combat effectiveness, and desired shooting frequency represents efficiency. The simulation environment deployed and simulated an enemy artillery unit with a size of 1,000m × 750m in the target area (6 guns), and applied the killing range of each firearm weapon system. For the description of the damage, the mathematical models Carlton damage function and the cookie cutter damage function were applied, and Monte Carlo simulation was applied to simulate the uncertainty of the battlefield. The results of the present study can be provided basic data to effectively operate and plan the firearm weapon systems