On 32-GHz cryogenically cooled HEMT low-noise amplifiers

The cryogenic noise temperature performance of a two-stage and a three-stage 32 GHz High Electron Mobility Transistor (HEMT) amplifier was evaluated. The amplifiers employ 0.25 micrometer conventional AlGaAs/GaAs HEMT devices, hybrid matching input and output microstrip circuits, and a cryogenically stable dc biasing network. The noise temperature measurements were performed in the frequency range of 31 to 33 GHz over a physical temperature range of 300 K down to 12 K. Across the measurement band, the amplifiers displayed a broadband response, and the noise temperature was observed to decrease by a factor of 10 in cooling from 300 K to 15 K. The lowest noise temperature measured for the two-stage amplifier at 32 GHz was 35 K with an associated gain of 16.5 dB, while the three-stage amplifier measured 39 K with an associated gain of 26 dB. It was further observed that both amplifiers were insensitive to light

A framework to investigate money attitudes and materialism

Purpose and/or objectives: This paper presents a framework to investigate money attitudes and materialistic values. The conceptualization of the framework is guided by a critical review of literature. The intention is to provide a framework that will be useful to examine how various childhood family experiences influence later-life consumption orientations. Problem investigated: The differences in family resources represent one of the biggest distinctions between an intact and a disrupted family. The underlining question is whether children raised in disrupted families will experience lower levels of family resources (economic and emotional) and find the experience stressful. If so, will these experiences influence them to adopt conservative money attitudes and be less materialistic or will they symbolically value money and be more materialistic? Design/methodology/approach: The development of a framework requires a critical review of secondary sources. The literature review is based on theories that provide an explanation of how childhood family experiences can affect the development of materialistic values and money attitudes. The secondary sources require careful scrutiny of journal articles, dissertations and essays in a number of libraries to provide more scholarly insight into the concepts and to assist in the conceptualisation of the framework. Findings and/or implications: Four main theories were found useful in conceptualizing the framework. They are Ryan and Deci's (2000) self-determination theory, Maslow's (1943) human need theory, Wicklund and Gollwitzer's (1982) symbolic self-completion theory and the life course theory contextualized by Moschis (2007). However, in line with Moschis' (2007) realization, the perspectives of the life course theory were found to be multi-disciplinary, multi-theoretical and thus innovative. They would therefore form the main theoretical guide for the design of the framework. Originality and/or value of the research: The paper provides a framework to investigate the moderating effect that money attitudes can have on how childhood family experiences influence later-life materialistic values. This proposed framework may form the building blocks for a number of empirical studies especially as the life course approach in studying consumption orientations is innovative and multidisciplinary. Conclusion: The framework includes as independent variable, childhood family structure. Depended variables are perceived level of family resources, stress and materialistic values. Money attitudes are regarded as moderating variables

Current research into brain barriers and the delivery of therapeutics for neurological diseases: a report on CNS barrier congress London, UK, 2017.

This is a report on the CNS barrier congress held in London, UK, March 22-23rd 2017 and sponsored by Kisaco Research Ltd. The two 1-day sessions were chaired by John Greenwood and Margareta Hammarlund-Udenaes, respectively, and each session ended with a discussion led by the chair. Speakers consisted of invited academic researchers studying the brain barriers in relation to neurological diseases and industry researchers studying new methods to deliver therapeutics to treat neurological diseases. We include here brief reports from the speakers