Damping of Electron Density Structures and Implications for Interstellar Scintillation

The forms of electron density structures in kinetic Alfven wave turbulence are studied in connection with scintillation. The focus is on small scales $L \sim 10^8-10^{10}$ cm where the Kinetic Alfv\'en wave (KAW) regime is active in the interstellar medium. MHD turbulence converts to a KAW cascade, starting at 10 times the ion gyroradius and continuing to smaller scales. These scales are inferred to dominate scintillation in the theory of Boldyrev et al. From numerical solutions of a decaying kinetic Alfv\'en wave turbulence model, structure morphology reveals two types of localized structures, filaments and sheets, and shows that they arise in different regimes of resistive and diffusive damping. Minimal resistive damping yields localized current filaments that form out of Gaussian-distributed initial conditions. When resistive damping is large relative to diffusive damping, sheet-like structures form. In the filamentary regime, each filament is associated with a non-localized magnetic and density structure, circularly symmetric in cross section. Density and magnetic fields have Gaussian statistics (as inferred from Gaussian-valued kurtosis) while density gradients are strongly non-Gaussian, more so than current. This enhancement of non-Gaussian statistics in a derivative field is expected since gradient operations enhance small-scale fluctuations. The enhancement of density gradient kurtosis over current kurtosis is not obvious, yet it suggests that modest fluctuation levels in electron density may yield large scintillation events during pulsar signal propagation in the interstellar medium. In the sheet regime the same statistical observations hold, despite the absence of localized filamentary structures. Probability density functions are constructed from statistical ensembles in both regimes, showing clear formation of long, highly non-Gaussian tails

Glycerol extends lifespan of Brachionus manjavacas (Rotifera) and protects against stressors

AbstractDiet has profound effects on animal longevity and manipulation of nutrient sensing pathways is one of the primary interventions capable of lifespan extension. This often is done through caloric restriction (CR) and a variety of CR mimics have been identified that produce life extending effects without adhering to the rigorous CR dietary regimen. Glycerol is a dietary supplement capable mimicking CR by shifting metabolism away from glycolysis and towards oxidative phosphorylation. Glycerol supplementation has a number of beneficial effects, including lifespan extension, improved stress resistance, and enhanced locomotory and mitochondria activity in older age classes. Using rotifers as a model, we show that supplements of 150–300mM glycerol produced 40–50% extension of mean lifespan. This effect was produced by raising glycerol concentration only three times higher than its baseline concentration in rotifer tissues. Glycerol supplementation decreased rotifer reliance on glycolysis and reduced the pro-aging effects of glucose. Glycerol also acted as a chemical chaperone, mitigating damage by protein aggregation. Glycerol treatment improved rotifer swimming performance in older age classes and maintained more mitochondrial activity. Glycerol treatment provided increased resistance to starvation, heat, oxidation, and osmotic stress, but not UV stress. When glycerol was co-administered with the hexokinase inhibitor 2-deoxyglucose, the lifespan extending effect of glycerol was enhanced. Co-administration of glycerol with inhibitors like 2-deoxyglucose can lower their efficacious doses, thereby reducing their toxic side effects

Influence of Personality on Ethical Decision-Making in Communication Sciences and Disorders

Purpose: A relationship between personality and ethical decision-making has been demonstrated in professions both within and outside of healthcare. However, this relationship has not been examined in the rehabilitation therapies, including speech-language pathology (SLP). Given the ethical dilemmas faced by therapists, it is important to assess this relationship and to modify ethical training when warranted. Methods: A total of 175 undergraduate communication sciences and disorders students participated in completing the Kiersey Temperament Sorter II and the Defining Issues Test-2. Scores were statistically compared to determine the relationship between the two assessments. Results: Based on a model of moral reasoning development, high scores on the DIT-2 are believed to correlate with post-conventional reasoning skills. Higher scores were statistically related to personality scores of strong introversion (I) and strong intuiting (N). Conclusion: Participants with strong introversion (I) and strong intuiting (N) traits may have natural skills for higher levels of moral reasoning. This implies that training modules for students and therapists should recognize personality differences and assist all individuals in developing best methods of problem solving in the face of specific personality traits

A quantum protocol for cheat-sensitive weak coin flipping

We present a quantum protocol for the task of weak coin flipping. We find that, for one choice of parameters in the protocol, the maximum probability of a dishonest party winning the coin flip if the other party is honest is 1/sqrt(2). We also show that if parties restrict themselves to strategies wherein they cannot be caught cheating, their maximum probability of winning can be even smaller. As such, the protocol offers additional security in the form of cheat sensitivity.Comment: 4 pages RevTex. Differs from the journal version only in that the sentences: "The ordering of the authors on this paper was chosen by a coin flip implemented by a trusted third party. TR lost." have not been remove

A Review of Empirical Studies Assessing Ethical Decision Making in Business

This article summarizes the multitude of empirical studies that test ethical decision making in business and suggests additional research necessary to further theory in this area. The studies are categorized and related to current theoretical ethical decision making models. The studies are related to awareness, individual and organizational factors, intent, and the role of moral intensity in ethical decision making. Summary tables provide a quick reference for the sample, findings, and publication outlet. This review provides insights for understanding organizational ethical decision constructs, where ethical decision making theory currently stands, and provides insights for future empirical work on organizational ethical decision making

Coherence and Intermittency of Electron Density in Small-Scale Interstellar Turbulence

Spatial intermittency in decaying kinetic Alfven wave turbulence is investigated to determine if it produces non Gaussian density fluctuations in the interstellar medium. Non Gaussian density fluctuations have been inferred from pulsar scintillation scaling. Kinetic Alfven wave turbulence characterizes density evolution in magnetic turbulence at scales near the ion gyroradius. It is shown that intense localized current filaments in the tail of an initial Gaussian probability distribution function possess a sheared magnetic field that strongly refracts the random kinetic Alfven waves responsible for turbulent decorrelation. The refraction localizes turbulence to the filament periphery, hence it avoids mixing by the turbulence. As the turbulence decays these long-lived filaments create a non Gaussian tail. A condition related to the shear of the filament field determines which fluctuations become coherent and which decay as random fluctuations. The refraction also creates coherent structures in electron density. These structures are not localized. Their spatial envelope maps into a probability distribution that decays as density to the power -3. The spatial envelope of density yields a Levy distribution in the density gradient.Comment: 31 pages, 3 figures. Replacement contains short additions to Secs. 6 and

Application of confocal surface wave microscope to self-calibrated attenuation coefficient measurement by Goos-Hänchen phase shift modulation

In this paper, we present a direct method to measure surface wave attenuation arising from both ohmic and coupling losses using our recently developed phase spatial light modulator (phase-SLM) based confocal surface plasmon microscope. The measurement is carried out in the far-field using a phase-SLM to impose an artificial surface wave phase profile in the back focal plane (BFP) of a microscope objective. In other words, we effectively provide an artificially engineered backward surface wave by modulating the Goos Hänchen (GH) phase shift of the surface wave. Such waves with opposing phase and group velocities are well known in acoustics and electromagnetic metamaterials but usually require structured or layered surfaces, here the effective wave is produced externally in the microscope illumination path. Key features of the technique developed here are that it (i) is self-calibrating and (ii) can distinguish between attenuation arising from ohmic loss (k″ Ω ) and coupling (reradiation) loss (k″ c ). This latter feature has not been achieved with existing methods. In addition to providing a unique measurement the measurement occurs of over a localized region of a few microns. The results were then validated against the surface plasmons (SP) dip measurement in the BFP and a theoretical model based on a simplified Green’s function

Patient-centred pharmaceutical design to improve acceptability of medicines : similarities and differences in paediatric and geriatric populations

Open Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.Patient acceptability of a medicinal product is a key aspect in the development and prescribing of medicines. Children and older adults differ in many aspects from the other age subsets of population and require particular considerations in medication acceptability. This review highlights the similarities and differences in these two age groups in relation to factors affecting acceptability of medicines. New and conventional formulations of medicines are considered regarding their appropriateness for use in children and older people. Aspects of a formulation that impact acceptability in these patient groups are discussed, including, for example, taste/smell/viscosity of a liquid and size/shape of a tablet. A better understanding of the acceptability of existing formulations highlights opportunities for the development of new and more acceptable medicines and facilitates safe and effective prescribing for the young and older populationsPeer reviewedFinal Published versio

Targeting the Ets Binding Site of the HER2/neu Promoter with Pyrrole-Imidazole Polyamides

Three DNA binding polyamides (1-3) were synthesized that bind with high affinity (Ka = 8.7·10^9 M^-1 to 1.4·10^10 M^-1) to two 7-base pair sequences overlapping the Ets DNA binding site (EBS; GAGGAA) within the regulatory region of the HER2/neu proximal promoter. As measured by electrophoretic mobility shift assay, polyamides binding to flanking elements upstream (1) or downstream (2 and 3) of the EBS were one to two orders of magnitude more effective than the natural product distamycin at inhibiting formation of complexes between the purified EBS protein, epithelial restricted with serine box (ESX), and the HER2/neu promoter probe. One polyamide, 2, completely blocked Ets-DNA complex formation at 10 nM ligand concentration, whereas formation of activator protein-2-DNA complexes was unaffected at the activator protein-2 binding site immediately upstream of the HER2/neu EBS, even at 100 nM ligand concentration. At equilibrium, polyamide 1 was equally effective at inhibiting Ets/DNA binding when added before or after in vitro formation of protein-promoter complexes, demonstrating its utility to disrupt endogenous Ets-mediated HER2/neu preinitiation complexes. Polyamide 2, the most potent inhibitor of Ets-DNA complex formation by electrophoretic mobility shift assay, was also the most effective inhibitor of HER2/neu promoter-driven transcription measured in a cell-free system using nuclear extract from an ESX- and HER2/neu-overexpressing human breast cancer cell line, SKBR-3

Defocus leakage radiation microscopy for single shot surface plasmon measurement

Measurement of surface plasmon and surface wave propagation is important for the operation and characterization of sensors and microscope systems. One challenge is to perform these measurements both quickly and with good spatial resolution without any modification to the sample surface. This paper addresses these issues by projecting an image of the field excited from a defocused sample to a magnified image plane. By carefully analysing the intensity distribution in this plane the properties of the surface waves generated on the sample surface can be determined. This has the advantage over previous techniques that the data can be obtained in a single shot without any changes to the focal position of the sample. Equally importantly, we show the method measures the local properties of the sample at well-defined positions, whereas other methods such as direct observation of the back focal plane average the properties over the propagation length of the surface waves