Balancing Selection Drives the Maintenance of Genetic Variation in Drosophila Antimicrobial Peptides

This work is licensed under a Creative Commons Attribution 4.0 International License.Genes involved in immune defense against pathogens provide some of the most well-known examples of both directional and balancing selection. Antimicrobial peptides (AMPs) are innate immune effector genes, playing a key role in pathogen clearance in many species, including Drosophila. Conflicting lines of evidence have suggested that AMPs may be under directional, balancing, or purifying selection. Here, we use both a linear model and control-gene-based approach to show that balancing selection is an important force shaping AMP diversity in Drosophila. In Drosophila melanogaster, this is most clearly observed in ancestral African populations. Furthermore, the signature of balancing selection is even more striking once background selection has been accounted for. Balancing selection also acts on AMPs in Drosophila mauritiana, an isolated island endemic separated from D. melanogaster by about 4 Myr of evolution. This suggests that balancing selection may be broadly acting to maintain adaptive diversity in Drosophila AMPs, as has been found in other taxa

The Genetic Basis of Natural Variation in Drosophila melanogaster Immune Defense against Enterococcus faecalis

This work is licensed under a Creative Commons Attribution 4.0 International License.Dissecting the genetic basis of natural variation in disease response in hosts provides insights into the coevolutionary dynamics of host-pathogen interactions. Here, a genome-wide association study of Drosophila melanogaster survival after infection with the Gram-positive entomopathogenic bacterium Enterococcus faecalis is reported. There was considerable variation in defense against E. faecalis infection among inbred lines of the Drosophila Genetics Reference Panel. We identified single nucleotide polymorphisms associated with six genes with a significant (p < 10−08, corresponding to a false discovery rate of 2.4%) association with survival, none of which were canonical immune genes. To validate the role of these genes in immune defense, their expression was knocked-down using RNAi and survival of infected hosts was followed, which confirmed a role for the genes krishah and S6k in immune defense. We further identified a putative role for the Bomanin gene BomBc1 (also known as IM23), in E. faecalis infection response. This study adds to the growing set of association studies for infection in Drosophila melanogaster and suggests that the genetic causes of variation in immune defense differ for different pathogens

Role of Kindness in Cancer Care

The wonders of high-tech cancer care are best complemented by the humanity of high-touch care. Simple kindnesses can help to diffuse negative emotions that are associated with cancer diagnosis and treatment-and may even help to improve patients\u27 outcomes. On the basis of our experience in cancer care and research, we propose six types of kindness in cancer care: deep listening , whereby clinicians take the time to truly understand the needs and concerns of patients and their families; empathy for the patient with cancer, expressed by both individual clinicians and the care culture, that seeks to prevent avoidable suffering; generous acts of discretionary effort that go beyond what patients and families expect from a care team; timely care that is delivered by using a variety of tools and systems that reduce stress and anxiety; gentle honesty, whereby the truth is conveyed directly in well-chosen, guiding words; and support for family caregivers, whose physical and mental well-being are vital components of the care their loved ones receive. These mutually reinforcing manifestations of kindness-exhibited by self-aware clinicians who understand that how care is delivered matters-constitute a powerful and practical way to temper the emotional turmoil of cancer for patients, their families, and clinicians themselves

The Detection of Ionizing Radiation by Plasma Panel Sensors: Cosmic Muons, Ion Beams and Cancer Therapy

The plasma panel sensor is an ionizing photon and particle radiation detector derived from PDP technology with high gain and nanosecond response. Experimental results in detecting cosmic ray muons and beta particles from radioactive sources are described along with applications including high energy and nuclear physics, homeland security and cancer therapeuticsComment: Presented at SID Symposium, June 201

Plasma Panel Sensors for Particle and Beam Detection

The plasma panel sensor (PPS) is an inherently digital, high gain, novel variant of micropattern gas detectors inspired by many operational and fabrication principles common to plasma display panels (PDPs). The PPS is comprised of a dense array of small, plasma discharge, gas cells within a hermetically-sealed glass panel, and is assembled from non-reactive, intrinsically radiation-hard materials such as glass substrates, metal electrodes and mostly inert gas mixtures. We are developing the technology to fabricate these devices with very low mass and small thickness, using gas gaps of at least a few hundred micrometers. Our tests with these devices demonstrate a spatial resolution of about 1 mm. We intend to make PPS devices with much smaller cells and the potential for much finer position resolutions. Our PPS tests also show response times of several nanoseconds. We report here our results in detecting betas, cosmic-ray muons, and our first proton beam tests.Comment: 2012 IEEE NS

Development of a plasma panel radiation detector: recent progress and key issues

A radiation detector based on plasma display panel technology, which is the principal component of plasma television displays is presented. Plasma Panel Sensor (PPS) technology is a variant of micropattern gas radiation detectors. The PPS is conceived as an array of sealed plasma discharge gas cells which can be used for fast response (O(5ns) per pixel), high spatial resolution detection (pixel pitch can be less than 100 micrometer) of ionizing and minimum ionizing particles. The PPS is assembled from non-reactive, intrinsically radiation-hard materials: glass substrates, metal electrodes and inert gas mixtures. We report on the PPS development program, including simulations and design and the first laboratory studies which demonstrate the usage of plasma display panels in measurements of cosmic ray muons, as well as the expansion of experimental results on the detection of betas from radioactive sources.Comment: presented at IEEE NSS 2011 (Barcelona

David Versus Goliath: Strategic Behavior of Small Firms In Consolidated Industries

This study assesses the effect of strategy selection and firm adaptability on small firm performance,  using firm  tenure  as a moderator  variable.  The study  is based  upon interviews with sixteen small firms operating in rapidly changing and consolidating industries. All of the firms in the study pursued a differentiation strategy. Half of the firms  pursued  a  broad product strategy and more than three-quarters pursued a broad service strategy. The study found that small firms adapt by addressing community needs and forming cooperative agreements with other small firms but not larger firms. Variation among the industries studied suggests that the intensity of industry concentration affects firm adaptation decisions. For instance, while the heavily concentrated hardware anti drugstore industries  showed limited adaptation, the unconsolidated bookstore industry showed greater commitment to adaptive strategies. In addition, firm tenure was found to affect the adaptation of the small firms  studied

Modern Laboratory-Based Education for Power Electronics and Electric Machines

The study of modern energy conversion draws upon a broad range of knowledge and often requires a fair amount of experience. This suggests that laboratory instruction should be an integral component of a power electronics and electric machines curriculum. However, before a single watt can be processed in a realistic way, the student must understand not only the operation of conversion systems but also more advanced concepts such as control theory, speed and position sensing, switching signal generation, gate drive isolation, circuit layout, and other critical issues. Our approach is to use a blue-box module where these details are pre-built for convenience, but not hidden from the students inside a black box. Recent improvements to our blue-box modules are described in this paper and include a dual-MOSFET control box with independently isolated FET devices, a triple silicon controlled rectifier control box, a discretely built, high quality pulse-width modulation inverter, a small discrete brushless dc drive system, and a high-performance computer-controlled brushless dc dynamometer motor drive system. Complete details, sufficient to allow the reader to duplicate these designs, are publicly available