Probing Mechanical Properties of Jurkat Cells under the Effect of ART Using Oscillating Optical Tweezers

Acute lymphoid leukemia is a common type of blood cancer and chemotherapy is the initial treatment of choice. Quantifying the effect of a chemotherapeutic drug at the cellular level plays an important role in the process of the treatment. In this study, an oscillating optical tweezer was employed to characterize the frequency-dependent mechanical properties of Jurkat cells exposed to the chemotherapeutic agent, artesunate (ART). A motion equation for a bead bound to a cell was applied to describe the mechanical characteristics of the cell cytoskeleton. By comparing between the modeling results and experimental results from the optical tweezer, the stiffness and viscosity of the Jurkat cells before and after the ART treatment were obtained. The results demonstrate a weak power-law dependency of cell stiffness with frequency. Furthermore, the stiffness and viscosity were increased after the treatment. Therefore, the cytoskeleton cell stiffness as the well as power-law coefficient can provide a useful insight into the chemo-mechanical relationship of drug treated cancer cells and may serve as another tool for evaluating therapeutic performance quantitatively

Supermarket Bakery Consumers: Attitudes, Preferences, Behaviors

R.B. 95-01For at least a decade, supermarket operators have turned increasingly to fresh foods for the strategic direction of their business by remodeling existing stores and building new stores to feature and emphasize produce, the delicatessen, the bakery, and other perishable departments. These departments have been the fastest growing and offer the greatest future sales potential as consumer demand for fresh and ready to eat prepared foods continues to grow. Despite these prospects, little is actually known about how consumers perceive and respond to product offerings and retailer initiatives in perishable departments. The objective ofthis report is to shed light on consumer attitudes and behavior with respect to one of the major supermarket perishable departments: the bakery. This report is based on a study which incorporated both primary and secondary sources of data (details in Section II). The primary data were collected through consumer surveys conducted nationwide by telephone and in-person at supermarkets in several regional market areas. A total of 700 consumers were surveyed. Additional primary data and insights were gathered through personal interviews with key supermarket bakery executives. Secondary data were gathered from trade reports, academic journals, and previously published research. The empirical results and analyses presented in Section III include such key findings as: • consumers consider convenience the most important reason for shopping supermarket bakeries, • the main reason some consumers do not buy baked goods in supermarkets is freshness, which is perceived to be better at local bakeries, • consumer awareness of health and nutrition concerns is greater than consumer knowledge about these issues, • about half of consumers are familiar with the United States Department of Agriculture's Food Guide Pyramid, but the percentage varies greatly by age with the youngest shoppers being most familiar, • consumers rate many of the most popular retailer promotional efforts as uninfluential factors in their purchase decisions, and • price plays only a minor role in bakery purchase decisions for most consumers. The implications of these findings and others are discussed in Section IV which also discusses opportunities for the supermarket bakery industry to respond to the consumer characteristics and issues identified in this study. The results present many marketing challenges for supermarket bakery managers as consumers increasingly make bakery decisions based on knowledge of health, nutrition, and other issues

Implementation and Impact of the Patient Self-Determination Act

The Patient Self-Determination Act became effective in December 1991 and mandates that patients be given information about legal rights regarding living wills and durable powers of attorney for health care. We investigated the impact this law has had on hospitals, medical personnel, and patients. We conducted a survey of all hospitals in the state of Georgia, collecting data regarding implementation and knowledge of the law, as well as effects of the law and beliefs about it. The data indicated that hospitals relied primarily on the Georgia Hospital Association for implementation policy, that minimalist implementation of the law occurs in most hospitals, and that the biggest perceived problem with the law was the inappropriateness of presenting this information at hospital admission and problems patients had in comprehending the materials presented. Despite these concerns, most respondents did not want the law repealed

Fuel Consumption Prediction for a Passenger Ferry using Machine Learning and In-service Data: A Comparative Study

As the importance of eco-friendly transportation increases, providing an efficient approach for marine vessel operation is essential. Methods for status monitoring with consideration to the weather condition and forecasting with the use of in-service data from ships requires accurate and complete models for predicting the energy efficiency of a ship. The models need to effectively process all the operational data in real-time. This paper presents models that can predict fuel consumption using in-service data collected from a passenger ship. Statistical and domain-knowledge methods were used to select the proper input variables for the models. These methods prevent over-fitting, missing data, and multicollinearity while providing practical applicability. Prediction models that were investigated include multiple linear regression (MLR), decision tree approach (DT), an artificial neural network (ANN), and ensemble methods. The best predictive performance was from a model developed using the XGboost technique which is a boosting ensemble approach. \rvv{Our code is available on GitHub at \url{https://github.com/pagand/model_optimze_vessel/tree/OE} for future research.Comment: 20 pages, 11 figures, 7 table

Compartmentalized PDE4A5 signaling impairs hippocampal synaptic plasticity and long-term memory

Alterations in cAMP signaling are thought to contribute to neurocognitive and neuropsychiatric disorders. Members of the cAMP-specific phosphodiesterase 4 (PDE4) family, which contains >25 different isoforms, play a key role in determining spatial cAMP degradation so as to orchestrate compartmentalized cAMP signaling in cells. Each isoform binds to a different set of protein complexes through its unique N-terminal domain, thereby leading to targeted degradation of cAMP in specific intracellular compartments. However, the functional role of specific compartmentalized PDE4 isoforms has not been examined in vivo. Here, we show that increasing protein levels of the PDE4A5 isoform in mouse hippocampal excitatory neurons impairs a long-lasting form of hippocampal synaptic plasticity and attenuates hippocampus-dependent long-term memories without affecting anxiety. In contrast, viral expression of a truncated version of PDE4A5, which lacks the unique N-terminal targeting domain, does not affect long-term memory. Further, overexpression of the PDE4A1 isoform, which targets a different subset of signalosomes, leaves memory undisturbed. Fluorescence resonance energy transfer sensor-based cAMP measurements reveal that the full-length PDE4A5, in contrast to the truncated form, hampers forskolin-mediated increases in neuronal cAMP levels. Our study indicates that the unique N-terminal localization domain of PDE4A5 is essential for the targeting of specific cAMP-dependent signaling underlying synaptic plasticity and memory. The development of compounds to disrupt the compartmentalization of individual PDE4 isoforms by targeting their unique N-terminal domains may provide a fruitful approach to prevent cognitive deficits in neuropsychiatric and neurocognitive disorders that are associated with alterations in cAMP signaling

Elemental Abundances in the X-Ray Gas of Early-Type Galaxies with XMM and Chandra Observations

The source of hot gas in elliptical galaxies is thought to be due to stellar mass loss, with contributions from supernova events and possibly from infall from a surrounding environment. This picture predicts supersolar values for the metallicity of the gas toward the inner part of the galaxy, which can be tested by measuring the gas phase abundances. We use high-quality data for 10 nearby early-type galaxy from XMM-Newton, featuring both the EPIC and the Reflection Grating Spectrometer, where the strongest emission lines are detected with little blending; some Chandra data are also used. We find excellent consistency in the elemental abundances between the different XMM instruments and good consistency with Chandra. Differences in abundances with aperture size and model complexity are examined, but large differences rarely occur. For a two-temperature thermal model plus a point source contribution, the median Fe and O abundances are 0.86 and 0.44 of the Solar value, while Si and Mg abundances are similar to that for Fe. This is similar to stellar abundances for these galaxies but supernovae were expected to enhance the gas phase abundances considerably, which is not observed.Comment: 35 pages, 10 figures, accepted for publication in Astrophysical Journa

A Systems Engineering Framework for Design, Construction and Operation of the Next Generation Nuclear Plant

Not since the International Space Station has a project of such wide participation been proposed for the United States. Ten countries, the European Union, universities, Department of Energy (DOE) laboratories, and industry will participate in the research and development, design, construction and/or operation of the fourth generation of nuclear power plants with a demonstration reactor to be built at a DOE site and operational by the middle of the next decade. This reactor will be like no other. The Next Generation Nuclear Plant (NGNP) will be passively safe, economical, highly efficient, modular, proliferation resistant, and sustainable. In addition to electrical generation, the NGNP will demonstrate efficient and cost effective generation of hydrogen to support the President’s Hydrogen Initiative. To effectively manage this multi-organizational and technologically complex project, systems engineering techniques and processes will be used extensively to ensure delivery of the final product. The technological and organizational challenges are complex. Research and development activities are required, material standards require development, hydrogen production, storage and infrastructure requirements are not well developed, and the Nuclear Regulatory Commission may further define risk-informed/performance-based approach to licensing. Detailed design and development will be challenged by the vast cultural and institutional differences across the participants. Systems engineering processes must bring the technological and organizational complexity together to ensure successful product delivery. This paper will define the framework for application of systems engineering to this $1.5B -$1.9B project