Low-Dose TOF-PET Based on Surface Electron Production in Dielectric Laminar MCPs

We present simulations of whole-body low-dose time-of-flight positron emission tomography (TOF-PET) based on the direct surface production [1] by 511 keV gamma rays of energetic electrons via the Photo-electric and Compton Effects, eliminating the scintillator and photodetector sub-systems in PET scanners. In Ref. [1] we described Microchannel Plates (MCP) constructed from thin dielectric laminae containing heavy nuclei such as lead or tungsten (LMCP$^{\rm{TM}}$). The laminae surfaces are micro-patterned to form channels, which can then be functionalized to support secondary electron emission in the manner of conventional MCPs. We have simulated direct conversion using modifications to the TOPAS Geant4-based tool kit. A 20 $\times$ 20 $\times$ 2.54 cm$^3$ LMCP, composed of 150-micron thick lead-glass laminae, is predicted to have a $\ge 30$% conversion efficiency to a primary electron that penetrates an interior wall of a pore. The subsequent secondary electron shower is largely confined to one pore and can provide high space and time resolutions. In whole-body PET scanners the technique eliminates the scintillator and photodetector subsystems. The consequent absence of a photocathode allows assembly of large arrays at atmospheric pressure and less stringent vacuum requirements, including use of pumped and cycled systems. TOPAS simulations of the Derenzo and XCAT-brain phantoms are presented with dose reductions of factors of 100 and 1000 from a literature benchmark. New applications of PET at a significantly lower radiation dose include routine screening for early detection of pathologies, the use in diagnostics in previously unserved patient populations such as children, and a larger installed facility base in rural and under-served populations, where simpler gamma detectors and lower radiation doses may enable small low-cost portable PET scanners.Comment: Version 9d incorporates reviewer comments during revision process. 22 pages, 18 figure

Increasing compliance with wearing a medical device in children with autism

Health professionals often recommend the use of medical devices to assess the health, monitor the well-being, or improve the quality of life of their patients. Children with autism may present challenges in these situations as their sensory peculiarities may increase refusals to wear such devices. To address this issue, we systematically replicated prior research by examining the effects of differential reinforcement of other behavior (DRO) to increase compliance with wearing a heart rate monitor in 2 children with autism. The intervention increased compliance to 100% for both participants when an edible reinforcer was delivered every 90 s. The results indicate that DRO does not require the implementation of extinction to increase compliance with wearing a medical device. More research is needed to examine whether the reinforcement schedule can be further thinned

Ebookness

Since the mid-2000s, the ebook has stabilized into an ontologically distinct form, separate from PDFs and other representations of the book on the screen. The current article delineates the ebook from other emerging digital genres with recourse to the methodologies of platform studies and book history. The ebook is modelled as three concentric circles representing its technological, textual and service infrastructure innovations. This analysis reveals two distinct properties of the ebook: a simulation of the services of the book trade and an emphasis on user textual manipulation. The proposed model is tested with reference to comparative studies of several ebooks published since 2007 and defended against common claims of ebookness about other digital textual genres

A biogeographic reversal in sexual size dimorphism along a continental temperature gradient

© 2018 The Authors The magnitude and direction of sexual size dimorphism (SSD) varies greatly across the animal kingdom, reflecting differential selection pressures on the reproductive and/or ecological roles of males and females. If the selection pressures and constraints imposed on body size change along environmental gradients, then SSD will vary geographically in a predictable way. Here, we uncover a biogeographical reversal in SSD of lizards from Central and North America: in warm, low latitude environments, males are larger than females, but at colder, high latitudes, females are larger than males. Comparisons to expectations under a Brownian motion model of SSD evolution indicate that this pattern reflects differences in the evolutionary rates and/or trajectories of sex-specific body sizes. The SSD gradient we found is strongly related to mean annual temperature, but is independent of species richness and body size differences among species within grid cells, suggesting that the biogeography of SSD reflects gradients in sexual and/or fecundity selection, rather than intersexual niche divergence to minimize intraspecific competition. We demonstrate that the SSD gradient is driven by stronger variation in male size than in female size and is independent of clutch mass. This suggests that gradients in sexual selection and male–male competition, rather than fecundity selection to maximize reproductive output by females in seasonal environments, are predominantly responsible for the gradient

Diffusion Tensor Imaging Detects Abnormalities in the Corticospinal Tracts of Neonates with Infantile Krabbe Disease

It is not possible to determine if babies diagnosed with Krabbe disease through statewide newborn screening programs will develop disease as infants, juveniles or adults. The only available treatment for this fatal neurodegenerative condition is unrelated umbilical cord transplantation but this treatment is only effective before clinical symptoms appear. Therefore, a marker of disease progression is needed. The purpose of this study was to evaluate the use of Diffusion Tensor Imaging (DTI) with fiber tracking in identifying early changes in major motor tracts of asymptomatic neonates with infantile Krabbe disease

Orchestration of Network Services Across Multiple Operators: The 5G Exchange Prototype

Future 5G networks will rely on the coordinated allocation of compute, storage, and networking resources in order to meet the functional requirements of 5G services as well as guaranteeing efficient usage of the network infrastructure. However, the 5G service provisioning paradigm will also require a unified infrastructure service market that integrates multiple operators and technologies. The 5G Exchange (5GEx) project, building heavily on the Software-Defined Network (SDN) and the Network Function Virtualization (NFV) functionalities, tries to overcome this market and technology fragmentation by designing, implementing, and testing a multi-domain orchestrator (MdO) prototype for fast and automated Network Service (NS) provisioning over multiple-technologies and spanning across multiple operators. This paper presents a first implementation of the 5GEx MdO prototype obtained by extending existing open source software tools at the disposal of the 5GEx partners. The main functions of the 5GEx MdO prototype are showcased by demonstrating how it is possible to create and deploy NSs in the context of a Slice as a Service (SlaaS) use-case, based on a multi-operator scenario. The 5GEx MdO prototype performance is experimentally evaluated running validation tests within the 5GEx sandbox. The overall time required for the NS deployment has been evaluated considering NSs deployed across two operators

Worker remittances and the global preconditions of ‘smart development’

With the growing environmental crisis affecting our globe, ideas to weigh economic or social progress by the ‘energy input’ necessary to achieve it are increasingly gaining acceptance. This question is intriguing and is being dealt with by a growing number of studies, focusing on the environmental price of human progress. Even more intriguing, however, is the question of which factors of social organization contribute to a responsible use of the resources of our planet to achieve a given social result (‘smart development’). In this essay, we present the first systematic study on how migration – or rather, more concretely, received worker remittances per GDP – helps the nations of our globe to enjoy social and economic progress at a relatively small environmental price. We look at the effects of migration on the balance sheets of societal accounting, based on the ‘ecological price’ of the combined performance of democracy, economic growth, gender equality, human development, research and development, and social cohesion. Feminism in power, economic freedom, population density, the UNDP education index as well as the receipt of worker remittances all significantly contribute towards a ‘smart overall development’, while high military expenditures and a high world economic openness are a bottleneck for ‘smart overall development’

A yearlong comparison of plot‐scale and satellite footprint‐scale 19 and 37 GHz brightness of the Alaskan North Slope

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95289/1/jgrd9836.pd

Amplified B Lymphocyte CD40 Signaling Drives Regulatory B10 Cell Expansion in Mice

Aberrant CD40 ligand (CD154) expression occurs on both T cells and B cells in human lupus patients, which is suggested to enhance B cell CD40 signaling and play a role in disease pathogenesis. Transgenic mice expressing CD154 by their B cells (CD154(TG)) have an expanded spleen B cell pool and produce autoantibodies (autoAbs). CD22 deficient (CD22(-/-)) mice also produce autoAbs, and importantly, their B cells are hyper-proliferative following CD40 stimulation ex vivo. Combining these 2 genetic alterations in CD154(TG)CD22(-/-) mice was thereby predicted to intensify CD40 signaling and autoimmune disease due to autoreactive B cell expansion and/or activation.CD154(TG)CD22(-/-) mice were assessed for their humoral immune responses and for changes in their endogenous lymphocyte subsets. Remarkably, CD154(TG)CD22(-/-) mice were not autoimmune, but instead generated minimal IgG responses against both self and foreign antigens. This paucity in IgG isotype switching occurred despite an expanded spleen B cell pool, higher serum IgM levels, and augmented ex vivo B cell proliferation. Impaired IgG responses in CD154(TG)CD22(-/-) mice were explained by a 16-fold expansion of functional, mature IL-10-competent regulatory spleen B cells (B10 cells: 26.7×10(6)±6 in CD154(TG)CD22(-/-) mice; 1.7×10(6)±0.4 in wild type mice, p<0.01), and an 11-fold expansion of B10 cells combined with their ex vivo-matured progenitors (B10+B10pro cells: 66×10(6)±3 in CD154(TG)CD22(-/-) mice; 6.1×10(6)±2 in wild type mice, p<0.01) that represented 39% of all spleen B cells.These results demonstrate for the first time that the IL-10-producing B10 B cell subset has the capacity to suppress IgG humoral immune responses against both foreign and self antigens. Thereby, therapeutic agents that drive regulatory B10 cell expansion in vivo may inhibit pathogenic IgG autoAb production in humans

Expanding Efficiency: Women\u27s Communication in Engineering

As engineering fields strive to be more inclusive of women, focusing on perceptions of women\u27s work is vital to understanding how women can succeed and the limitations they may face. One area in need of more attention is the connection between communication and women\u27s experiences in engineering. This article examines the gendered nature of writing labor in engineering, focusing on case studies of three women who were able to use writing effectively, yet how communication emerged as a gendered form of labor subject to gendered perceptions. While these women\u27s communication skills led to professional success, their association with writing echoes a historical division, where writing is viewed as less valuable than technical knowledge. This division has the potential to disadvantage women who are asked to take on more writing-related tasks. In addition, their writing and communication are subject to gendered perceptions of being ‘chatty’ or blunt rather than effective or efficient. Articulating these perceptions and attitudes can lead to a breakdown of the binary between writing and technical labor as well as appropriately valuing the contributions women make in engineering through writing