4-Methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene,a Major Active Metabolite of Bisphenol A,Triggers Pancreatic β-Cell Death via a JNK/AMPKα Activation-Regulated Endoplasmic Reticulum Stress-Mediated Apoptotic Pathway

4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP), a major active metabolite of bisphenol A (BPA), is generated in the mammalian liver. Some studies have suggested that MBP exerts greater toxicity than BPA. However, the mechanism underlying MBP-induced pancreatic β-cell cytotoxicity remains largely unclear. This study demonstrated the cytotoxicity of MBP in pancreatic β-cells and elucidated the cellular mechanism involved in MBP-induced β-cell death. Our results showed that MBP exposure significantly reduced cell viability, caused insulin secretion dysfunction, and induced apoptotic events including increased caspase-3 activity and the expression of active forms of caspase-3/-7/-9 and PARP protein. In addition, MBP triggered endoplasmic reticulum (ER) stress, as indicated by the upregulation of GRP 78, CHOP, and cleaved caspase-12 proteins. Pretreatment with 4-phenylbutyric acid (4-PBA; a pharmacological inhibitor of ER stress) markedly reversed MBP-induced ER stress and apoptosis-related signals. Furthermore, exposure to MBP significantly induced the protein phosphorylation of JNK and AMP-activated protein kinase (AMPK)α. Pretreatment of β-cells with pharmacological inhibitors for JNK (SP600125) and AMPK (compound C), respectively, effectively abrogated the MBP-induced apoptosis-related signals. Both JNK and AMPK inhibitors also suppressed the MBP-induced activation of JNK and AMPKα and of each other. In conclusion, these findings suggest that MBP exposure exerts cytotoxicity on β-cells via the interdependent activation of JNK and AMPKα, which regulates the downstream apoptotic signaling pathway.     

Experimental and CFD study on the mass flow-rate characteristic of gas through orifice-type restrictor in aerostatic bearings

This paper describes the experimental and CFD study on the mass flow-rate characteristic through an orifice-type restrictor in aerostatic bearings. In the conventional design of gas-lubricated aerostatic bearings, the mass flow-rate of gas through an orifice-type restrictor is generally derived from a well-known mathematical model, which is originally developed to describe the mass flow-rate property through an ideal nozzle. It is reasonable to doubt if there is any difference between the property of mass flow-rate through an orifice and that through a nozzle. In this paper, therefore, a series of simulations and experiments are carried out and the results show that the mass flow-rate characteristic through an orifice is different from that through a nozzle. Consequently, the conventional model to determine the mass flow-rate through an orifice-type restrictor in aerostatic bearings may have to be updated to the proposed new model for more precise design and modelling of the gas-lubricated aerostatic bearings.     

Multiparameter microscopy and spectroscopy for single-molecule analytics

The ability to monitor several parameters simultaneously from distinct individual fluorescent reporter molecules facilitates the disentanglement of complex and interacting systems and opens new perspectives in areas from basic science to biopharmaceutical technology. By combining annular illumination microscopy, time-correlated single-photon counting, and multichannel detection, we were able to determine 14 independent parameters from one individual fluorophore. The whole set of parameters was deduced from the few properties of the fluorescence photons, i.e., arrival time, wavelength, and polarization. With this approach, the intensity, the polarization, and the spectral dynamics can be analyzed on a nanosecond time scale and the mean values can be monitored with submillisecond time resolution. Nanosecond spectral dynamics of single molecules has been observed, to the best of our knowledge, for the first time. From our experience, we can determine all parameters for more than 30% of the illuminated fluorophores in biological samples and for more than 80% in doped polymeric films.     

Printed Sub‐2 V Gel‐Electrolyte‐Gated Polymer Transistors and Circuits

The fabrication and characterization of printed ion‐gel‐gated poly(3‐hexylthiophene) (P3HT) transistors and integrated circuits is reported, with emphasis on demonstrating both function and performance at supply voltages below 2 V. The key to achieving fast sub‐2 V operation is an unusual gel electrolyte based on an ionic liquid and a gelating block copolymer. This gel electrolyte serves as the gate dielectric and has both a short polarization response time (<1 ms) and a large specific capacitance (>10 µF cm^?2), which leads simultaneously to high output conductance (>2 mS mm^?1), low threshold voltage (<1 V) and high inverter switching frequencies (1–10 kHz). Aerosol‐jet‐printed inverters, ring oscillators, NAND gates, and flip‐flop circuits are demonstrated. The five‐stage ring oscillator operates at frequencies up to 150 Hz, corresponding to a propagation delay of 0.7 ms per stage. These printed gel electrolyte gated circuits compare favorably with other reported printed circuits that often require much larger operating voltages. Materials factors influencing the performance of the devices are discussed.     

Aerosol-jet-printed, high-speed, flexible thin-film transistor made using single-walled carbon nanotube solution

A high-purity, surfactant-free and stable SWCNT aqueous solution was prepared using a series of chemical and physical processes. The SWCNT solution has a very limited amount of carbonaceous impurities, if any, and a total metal content of well below 500 ppb. It is stable for months without the addition of surfactant. Such SWCNT aqueous solution enables ink-jet printing of the entire fast, flexible SWCNT-based field-effect thin-film transistor (FE-TFT) at room temperature without the engagement of any traditional dry or wet chemical processes used for fabricating silicon-based transistors. High-speed SWCNT-based flexible FE-TFTs were printed using Aerosol Jet^® printing technology. The printed flexible FE-TFTs were characterized to have a current ON-OFF ratio of greater than 130 with an operation frequency of greater than 5 GHz.     

The role of risk perception for risk management

Are risks social constructions of different societal actors that can be checked at best against standards of consistency, cohesion and internal conventions of deduction, but cannot claim any validity outside of the actor's logical framework? Or are technical estimates of risk representations of real hazards that can and will affect people as predicted by the statistical values, regardless of the beliefs or convictions of those who conduct the assessments? Which of the two sides one takes determines the legitimate function of risk perception for management purposes. The paper argues that both extremes, the constructivist and the realist perspective, miss the point, as risks are always mental representations of threats that are capable of claiming real losses. Over the last two decades, risk analysts have dealt with both sides of risk in an additive fashion. In times in which risk management has been under serious pressure to demonstrate effectiveness and cost-efficiency, the parallel approach of pleasing the technical elite and the public alike has lost legitimacy. In order to integrate risk assessment and perception, the paper analyses the strengths and weaknesses of each approach to risk analysis and highlights the potential contributions that the technical sciences and the social sciences can offer to risk management. Technical assessments provide the best estimate for judging the average probability of an adverse effect linked to an object or activity. First, public perception should govern the selection of criteria on which acceptability or tolerability are to be judged. Second, public input is needed to determine the trade-offs between criteria. Third, public preferences are needed to design resilient strategies for coping with remaining uncertainties. A public participation model is introduced that promises an integration of analytic knowledge and deliberative process involving those who will be affected by the respective risk.     

A developmental-contextual model of couples coping with chronic illness across the adult life span.

A developmental-contextual model of couples coping with chronic illness is presented that views chronic illness as affecting the adjustment of both the patient and the spouse such that coping strategies enacted by the patient are examined in relation to those enacted by the spouse, and vice versa. The developmental model emphasizes that dyadic coping may be different at various phases of the life span, changing temporally at different stages of dealing with the illness as well as unfolding daily as spouses interact around dyadic stressors. In addition, couples engaged in dyadic coping are affected by broad sociocultural factors (culture and gender) as well as more proximal contextual factors (quality of the marital relationship and the specific demands of the chronic illness). The model provides a framework for understanding how couples coping with chronic illness may together appraise and cope with illness during adulthood and for determining when spousal involvement is beneficial or harmful to both patient and spousal adjustment. The developmental-contextual model to dyadic appraisal and coping has numerous research implications for the field, and the authors conclude with specific recommendations for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)