Microfilm and Microfacsimile Publications

published or submitted for publicatio

Power beaming options

Some large scale power beaming applications are proposed for the purpose of stimulating research. The first proposal is for a combination of large phased arrays on the ground near power stations and passive reflectors in geostationary orbit. The systems would beam excess electrical power in microwave form to areas in need of electrical power. Another proposal is to build solar arrays in deserts and beam the energy around the world. Another proposal is to use lasers to beam energy from earth to orbiting spacecraft

Proceedings of the Near-Earth-Object Interception Workshop

The National Aeronautics and Space Administration Headquarters sponsored the Near-Earth-Object Interception Workshop hosted by the Los Alamos National Laboratory on 14-16 Jan. 1992 at the J. Robert Oppenheimer Study Center in Los Alamos, New Mexico. The Workshop evaluated the issues involved in intercepting celestial objects that could hit the Earth. It covered the technologies for acquiring, tracking, and homing, as well as those for sending interceptors to inspect, rendezvous with, land on, irradiate, deflect, or destroy them. This report records the presentations and technical options reviewed

Deep Learning Assisted Robust Detection Techniques for a Chipless RFID Sensor Tags

In this paper, we present a new approach for robust reading of identification and sensor data from chipless RFID sensor tags. For the first time, Machine Learning (ML) and Deep Learning (DL) regression modelling techniques are applied to a dataset of measured Radar Cross Section (RCS) data that has been derived from large-scale robotic measurements of custom-designed, 3-bit chipless RFID sensor tags. The robotic system is implemented using the first-of-its-kind automated data acquisition method using an ur16e industry-standard robot. A large data set of 9,600 Electromagnetic (EM) RCS signatures collected using the automated system is used to train and validate four ML models and four 1-dimensional Convolutional Neural Network (1D CNN) architectures. For the first time, we report an end-to-end design and implementation methodology for robust detection of identification (ID) and sensing data using ML/DL models. Also, we report, for the first time, the effect of varying tag surface shapes, tilt angles, and read ranges that were incorporated into the training of models for robust detection of ID and sensing values. The results show that all the models were able to generalise well on the given data. However, the 1D CNN models outperformed the conventional ML models in the detection of ID and sensing values. The best 1D CNN model architectures performed well with a low Root Mean Square Error (RSME) of 0.061 (0.87%) for tag ID and 0.0241 (3.44%) error for the capacitive sensing

Theoretical models for underwater RFID

Underwater wireless communications pose challenges due to the characteristics of water as a propagation channel medium. Regardless, it is needed for a range of systems that operate underwater. Commonly used technologies for these use cases (radio-frequency, acoustic and optical communications) are lacking, as they usually suffer from strong attenuation, multipath and propagation delays. In this context, we explore Radio Frequency Identification (RFID) systems underwater and the feasibility of their application. This paper aims to discuss the theoretical transmission models for RFID systems underwater, separating them into near-field systems -- which use Magnetic Induction (MI) to communicate -- and far-field systems -- that transfer data via Radio Frequency (RF). We determine the path loss for each case, explore its value for different system configurations and present preliminary measurements of magnetic field strength

Histone chaperone HIRA deposits histone H3.3 onto foreign viral DNA and contributes to anti-viral intrinsic immunity

The HIRA histone chaperone complex deposits histone H3.3 into nucleosomes in a DNA replication- and sequence-independent manner. As herpesvirus genomes enter the nucleus as naked DNA, we asked whether the HIRA chaperone complex affects herpesvirus infection. After infection of primary cells with HSV or CMV, or transient transfection with naked plasmid DNA, HIRA re-localizes to PML bodies, sites of cellular anti-viral activity. HIRA co-localizes with viral genomes, binds to incoming viral and plasmid DNAs and deposits histone H3.3 onto these. Anti-viral interferons (IFN) specifically induce HIRA/PML co-localization at PML nuclear bodies and HIRA recruitment to IFN target genes, although HIRA is not required for IFN-inducible expression of these genes. HIRA is, however, required for suppression of viral gene expression, virus replication and lytic infection and restricts murine CMV replication in vivo. We propose that the HIRA chaperone complex represses incoming naked viral DNAs through chromatinization as part of intrinsic cellular immunity

Theoretical models for underwater RFID and the impact of water salinity on the design of wireless systems

Underwater wireless communications present challenges due to the characteristics of water as a propagation channel medium. Regardless, wireless communications are needed for a range of systems that operate underwater. Commonly used technologies for these use cases (radio-frequency, acoustic and optical communications) are lacking, as they generally suffer from strong attenuation, multipath effects and propagation delays. In this context, we explore the theoretical models for Path Loss of Radio Frequency Identification (RFID) systems underwater in regards to the salinity of the water. We also discuss RFID systems feasibility in such applications as aquaculture and fish stock management. This paper aims to discuss the theoretical transmission models for RFID systems underwater, separating them into near-field systems – which use Magnetic Induction (MI) to communicate – and far-field systems – that transfer data via Radio Frequency (RF). We determine the path loss for each case, the effect of the salinity in the model for the path loss, and present preliminary measurements of magnetic field strength underwater for different salinity values

Diverse interventions that extend mouse lifespan suppress shared age-associated epigenetic changes at critical gene regulatory regions

Background: Age-associated epigenetic changes are implicated in aging. Notably, age-associated DNA methylation changes comprise a so-called aging “clock”, a robust biomarker of aging. However, while genetic, dietary and drug interventions can extend lifespan, their impact on the epigenome is uncharacterised. To fill this knowledge gap, we defined age-associated DNA methylation changes at the whole-genome, single-nucleotide level in mouse liver and tested the impact of longevity-promoting interventions, specifically the Ames dwarf Prop1 df/df mutation, calorie restriction and rapamycin. Results: In wild-type mice fed an unsupplemented ad libitum diet, age-associated hypomethylation was enriched at super-enhancers in highly expressed genes critical for liver function. Genes harbouring hypomethylated enhancers were enriched for genes that change expression with age. Hypermethylation was enriched at CpG islands marked with bivalent activating and repressing histone modifications and resembled hypermethylation in liver cancer. Age-associated methylation changes are suppressed in Ames dwarf and calorie restricted mice and more selectively and less specifically in rapamycin treated mice. Conclusions: Age-associated hypo- and hypermethylation events occur at distinct regulatory features of the genome. Distinct longevity-promoting interventions, specifically genetic, dietary and drug interventions, suppress some age-associated methylation changes, consistent with the idea that these interventions exert their beneficial effects, in part, by modulation of the epigenome. This study is a foundation to understand the epigenetic contribution to healthy aging and longevity and the molecular basis of the DNA methylation clock

Computerized Ultrasound Risk Evaluation (CURE) System: Development of Combined Transmission and Reflection Ultrasound with New Reconstruction Algorithms for Breast Imaging

Our Computerized Ultrasound Risk Evaluation (CURE) system has been developed to the engineering prototype stage and generated unique data sets of both transmission and reflection ultrasound (US). This paper will help define the clinical underpinnings of the developmental process and interpret the imaging results from a similar perspective. The CURE project was designed to incorporate numerous diagnostic parameters to improve upon two major areas of early breast cancer detection. CURE may provide improved tissue characterization of breast masses and reliable detection of abnormal microcalcifications found in some breast cancers and ductal carcinoma in situ (DCIS). Current breast US is limited to mass evaluation, whereas mammography also detects and guides biopsy of malignant calcifications. Screening with CURE remains a distant goal, but improved follow-up of mammographic abnormalities may represent a feasible breakthrough. Improved tissue characterization could result in reduction of the estimated one million benign biopsies each year in the United States, costing up to several billion dollars. Most breast calcifications are benign and comprise-80% of stereotactic biopsies guided by mammography. Ultrasound has the capability of finding some groups of calcifications, but further improvements in resolution should also address tissue characterization to define the soft tissue filling of ducts by DCIS. In this manner, CURE may be able to more accurately identify the malignant calcifications associated with progression of DCIS or early cancers. Currently, high-resolution US images of the breast are performed in the reflection mode at higher frequencies, which also limits depth of penetration. Reconstruction of reflection ultrasound images relies upon acoustic impedance differences in the tissue and includes only direct backscatter of the ultrasound signal. Resolution and tissue contrast of current US continues to improve with denser transducer arrays and image processing, but the operator dependent nature of using a moveable transducer head remains a significant problem for thorough coverage of the entire breast. We have therefore undertaken the development of a whole breast (i.e., including auxiliary tail) system, with improved resolution and tissue characterization abilities. The extensive ultrasound physics considerations, engineering, materials process development and subsequent algorithm reconstruction are beyond the scope of this initial paper. The proprietary nature of these processes will be forthcoming as the intellectual property is fully secured. We will focus here on the imaging outcomes as they apply to eventual expansion into clinical use