On the existence of orthonormal geodesic bases for Lie algebras

We show that every unimodular Lie algebra, of dimension at most 4, equipped with an inner product, possesses an orthonormal basis comprised of geodesic elements. On the other hand, we give an example of a solvable unimodular Lie algebra of dimension 5 that has no orthonormal geodesic basis, for any inner product

Kynurenine Pathway Metabolism is Involved in the Maintenance of the Intracellular NAD+ Concentration in Human Primary Astrocytes

Efficient synthesis of NAD+ is critical to maintaining cell viability in all organs of the body. However, little is known of the pathway(s) by which cells of the central nervous system produce NAD+. The aim of this study was to investigate the relationship, between tryptophan degradation via the kynurenine pathway (KP) and de novo NAD+ synthesis in human astrocytes, a major cell type within the brain. In this study we observed that inhibition of single enzymes of the KP resulted in significant decreases in NAD+ levels in astroglial cells after a 24 hr period. We also observed that astrocytes cultured in media deficient in tryptophan, nicotinic acid and nicotinamide resulted in a 50% decrease in NAD+ levels after 24 hrs. This decrease in NAD+ was partially restored by supplementation of the culture media with either tryptophan or kynurenine, or nicotinic acid or with supply of the salvage pathway precursor nicotinamide

A monolithic resonant terahertz sensor element comprising a metamaterial absorber and micro-bolometer

In this article a monolithic resonant terahertz sensor element with a noise equivalent power superior to that of typical commercial room temperature single pixel terahertz detectors and capable of close to real time read-out rates is presented. The detector is constructed via the integration of a metamaterial absorber and a micro-bolometer sensor. An absorption magnitude of 57% at 2.5 THz, a minimum NEP of inline image and a thermal time constant of 68 ms for the sensor are measured. As a demonstration of detector capability, it is employed in a practical Nipkow terahertz imaging system. The monolithic resonant terahertz detector is readily scaled to focal plane array formats by adding standard read-out and addressing circuitry enabling compact, low-cost terahertz imaging

Evolutionary tracks for Betelgeuse

We have constructed a series of non-rotating quasi-hydrostatic evolutionary models for the M2 Iab supergiant Betelgeuse ($\alpha~Orionis$). Our models are constrained by multiple observed values for the temperature, luminosity, surface composition and mass loss for this star, along with the parallax distance and high resolution imagery that determines its radius. We have then applied our best-fit models to analyze the observed variations in surface luminosity and the size of detected surface bright spots as the result of up-flowing convective material from regions of high temperature in the surface convective zone. We also attempt to explain the intermittently observed periodic variability in a simple radial linear adiabatic pulsation model. Based upon the best fit to all observed data, we suggest a best progenitor mass estimate of $20 ^{+5}_{-3} M_\odot$ and a current age from the start of the zero-age main sequence of $8.0 - 8.5$ Myr based upon the observed ejected mass while on the giant branch.Comment: 27 pages, 11 figures, Revised per referee suggestions, Accepted for publication in the Astrophysical Journa

Security Breach: The Case of TJX Companies, Inc.

TJX Companies Inc. is a leading off-price apparel and home fashions retailer with headquarters situated in the United States. In late 2006, the company discovered it was victim to a massive security breach which compromised millions of customer records. Despite the internal exchanges within the IT department concerning the upgrade of their wireless security standard protocol, the company opted for cost savings rather than increased spending. As the company financials took a hit, the company was faced with pending lawsuits from credit card companies and affected customers; government scrutiny of IT security standards; loss of consumer confidence; among other concerns. Though it has not yet concluded the extent of the financial impact of this incident, analysts estimate the full cost of the breach might amount up to one billion dollars. This case presents a “wake-up call” for retail companies about the importance of IT security

Insights into Hydration Dynamics and Cooperative Interactions in Glycerol-Water Mixtures by Terahertz Dielectric Spectroscopy.

We report relaxation dynamics of glycerol-water mixtures as probed by megahertz-to-terahertz dielectric spectroscopy in a frequency range from 50 MHz to 0.5 THz at room temperature. The dielectric relaxation spectra reveal several polarization processes at the molecular level with different time constants and dielectric strengths, providing an understanding of the hydrogen-bonding network in glycerol-water mixtures. We have determined the structure of hydration shells around glycerol molecules and the dynamics of bound water as a function of glycerol concentration in solutions using the Debye relaxation model. The experimental results show the existence of a critical glycerol concentration of ∼7.5 mol %, which is related to the number of water molecules in the hydration layer around a glycerol molecule. At higher glycerol concentrations, water molecules dispersed in a glycerol network become abundant and eventually dominate, and four distinct relaxation processes emerge in the mixtures. The relaxation dynamics and hydration structure in glycerol-water mixtures are further probed with molecular dynamics simulations, which confirm the physical picture revealed by the dielectric spectroscopy

CAPIR: Collaborative Action Planning with Intention Recognition

We apply decision theoretic techniques to construct non-player characters that are able to assist a human player in collaborative games. The method is based on solving Markov decision processes, which can be difficult when the game state is described by many variables. To scale to more complex games, the method allows decomposition of a game task into subtasks, each of which can be modelled by a Markov decision process. Intention recognition is used to infer the subtask that the human is currently performing, allowing the helper to assist the human in performing the correct task. Experiments show that the method can be effective, giving near-human level performance in helping a human in a collaborative game.Comment: 6 pages, accepted for presentation at AIIDE'1

Incorporating a clinical pharmacist in an outpatient palliative care team

Title: Incorporating a clinical pharmacist in an outpatient palliative care team Crystal Rim, PharmD; Sharon Leigh, PharmD, BCPS; Linda De Sitter MD, MPH; Mary Grant, ANP; Dana Nguyen, PharmD Palliative care is a growing field in medicine that focuses on delivering care that improves quality of life for patients with serious illnesses. Often, the goals of palliative care differ from traditional goals of medicine. Currently, there is limited data demonstrating the integration of pharmacists in the palliative care setting. The purpose of this quality improvement is to evaluate the clinical pharmacist’s role within an outpatient palliative care team when performing medication reconciliation and review. Medication review includes de-prescribing high-risk medications and optimizing medications in symptom management. Between January and February 2020, the clinical pharmacist interviewed patients referred to the outpatient palliative care service through three different methods: telehealth, pharmacy consult and telephone. The clinical pharmacist provided recommendations to the outpatient palliative care nurse practitioner and primary care provider for medication optimization, symptom management and de-prescribing based on STOPPFrail and Beers Criteria. Data from 19 patients were analyzed. One patient was excluded from analysis due to death. Five patients were interviewed through telehealth. Two patients were directly consulted for pharmacist review by the outpatient palliative care nurse practitioner. Seven patients were interviewed through telephone, of which 4 patients were referred to hospice following palliative care consult. Of 19 patients, 64 total recommendations (29 medication discontinuation, 30 medication optimization, 5 symptom management) were made. Six recommendations were accepted by the provider (3 medication discontinuation, 3 medication optimization). The average time spent on chart review for each patient was 1.5 hours. Pharmacist involvement in outpatient palliative care may be valuable. However, many barriers to providing meaningful interventions were identified in this study. While telehealth provided the convenience to the patient and caregivers, utilization was limited due to lack of standardization of technology. Telephone interviews allowed proper medication reconciliation prior to the palliative care visit, but non-medication related issues may be prioritized after the visit. Finally, pharmacy consult from palliative care nurse practitioners allowed more efficiency, but it did not allow formal pharmacist integration in the outpatient palliative care team. Further studies quantifying the pharmacist role in outpatient palliative care are warranted.https://digitalcommons.psjhealth.org/pharmacy_PGY1mn/1000/thumbnail.jp

Optimal aeroassisted intercept trajectories at hyperbolic speeds

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76250/1/AIAA-1989-3444-892.pd

Optimal aeroassisted intercept trajectories at hyperbolic speeds

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76040/1/AIAA-20613-974.pd