Transport studies in laser plasma interactions

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Diet Analysis of Burbot from Eastern Lake Michigan: 1999-2012

The Lake Michigan fish community has undergone many changes due to introduction of non-native species, climate shifts, and management actions. Managers need to understand the time course of these alterations, including the time-frame of impact on the food web in the lake. I used a collection (1999-2012) of diet samples from burbot from eastern Lake Michigan to evaluate temporal alterations in burbot diet with particular attention to non-native vs. native forage. Catch per unit effort (burbot/net · day) decreased from a high of 5.82 burbot/net · day (± 2.19) in 2001 to a low of 0.750 burbot/net · day (± 0.25) in 2010, which is consistent with declining burbot populations throughout the Great Lakes (Gorman and Sitar 2013; Stapanian et al. 2013). The collective contribution of sculpin (Cottus), alewife (Alosa pseudoharengus), and ninespine stickleback (Pungitius pungitius) to burbot diet decreased from ~80% before 2006 to ~15% in 2012. During the same time span, round goby (Neogobius melanostomus) contribution to burbot diet increased from ~0% before 2006 to greater than 60% in 2012, implying nearly a complete diet shift of burbot in just six years. The diet shift suggests a change in feeding behavior from partially pelagic/benthic to almost entirely benthic, and a change in prey consumption from alewife/sculpin to round goby. This shift may and serve as a potential link to move the benthos from a nutrient sink to a nutrient source by utilizing round gobies and moving nutrients up the trophic web

Development of low-cost instrumentation for single point autofluorescence lifetime measurements

Autofluorescence lifetime measurements, which can provide label-free readouts in biological tissues, contrasting e.g. different types and states of tissue matrix components and different cellular metabolites, may have significant clinical potential for diagnosis and to provide surgical guidance. However, the cost of the instrumentation typically used currently presents a barrier to wider implementation. We describe a low-cost single point time-resolved autofluorescence instrument, exploiting modulated laser diodes for excitation and FPGA-based circuitry for detection, together with a custom constant fraction discriminator. Its temporal accuracy is compared against a “gold-standard” instrument incorporating commercial TCSPC circuitry by resolving the fluorescence decays of reference fluorophores presenting single and double exponential decay profiles. To illustrate the potential to read out intrinsic contrast in tissue, we present preliminary measurements of autofluorescence lifetime measurements of biological tissues ex vivo. We believe that the lower cost of this instrument could enhance the potential of autofluorescence lifetime metrology for clinical deployment and commercial development

The effect of different queuing regimes on a Switched Ethernet fronthaul

This paper investigates the effects of different queuing regimes on the mean and standard deviation of the frame inter-arrival delay of a LTE traffic stream under the presence of background Ethernet traffic. The background traffic is used to represent traffic that would be generated by different functional subdivisions in the physical layer of traditional LTE base station. In this work, a Switched Ethernet architecture is used as the fronthaul section of a Cloud Radio Access Network (C-RAN). Contention in this fronthaul becomes an important issue since different traffic streams originating from different functional subdivisions with different quality of service specifications will be transmitted over the same physical links. Trunk ports then, will have to handle the queuing management and prioritization. Handling the traffic with different queuing regimes will reflect on the latency and latency variations of the LTE traffic

The researcher role in the attitude-behaviour gap

In the green consumer behaviour literature the attitude-behaviour gap is well-established. Studies show that although people condone environmentally friendly actions, their green attitudes do not necessarily translate into green behaviours. Even when green behaviours are reported, this is not borne out by sales figures or recycling rates. The attitude-behaviour gap has been debated across disciplines researching different aspects of green consumer behaviour, such as recycling, purchasing green energy, or household goods. Researchers have debated how attitudes and behaviours may be related or unrelated. Within the field of sustainable tourism researchers have used these ideas to investigate tourist attitudes and behaviours with respect to flying. Our research falls within this tradition. Data from two studies of the flying behaviour of green consumers have raised the question of whether researchers are erroneously equating attitudes with behaviour because of how questions are presented and data are interpreted. We contend that this may be contributing to the attitude-behaviour gap

The new flexible mobile fronthaul: Digital or analog, or both?

It has become apparent that current fronthaul technology cannot be simply extended to meet the projected demands of 5G and beyond mobile systems. This current technology, based on the transport of sampled radio waveforms, has been the preferred option, with analog radio over fiber reserved to relatively niche application scenarios. However, for future systems, it is recognised that different functional splits between the central location and the remote units are needed; sampled waveform transport is not scalable to these systems. We propose a flexible fronthaul, therefore, in which both digital and analog transport technologies can coexist. Using practical examples from our work, we describe where these technologies can be used in the future fronthaul

Statistical distribution of packet inter-arrival rates in an Ethernet fronthaul

This paper investigates the effects of background traffic streams in the packet inter-arrival rates of an LTE traffic stream, when these streams are transported over the same Ethernet fronthaul network. Contention of background traffic with LTE traffic can occur in a Cloud-RAN that is transporting traffic streams originating from Constant Bit-Rate (CBR) sources such as the Common Public Radio Interface (CPRI) and from other non-CBR sources originating from different LTE physical layer functional subdivisions. Packet inter-arrival statistics are important in such a network, as they can be used to estimate and/or predict buffer sizes in receiving network nodes. Buffer management will also be important for traffic streams originating from functional splits (such as direct LTE MAC transport block transportation) where user plane data and control primitives have to be time aligned at the receiving node

Patient–provider perceptions of diabetes and its impact on self-management: a comparison of African-American and White patients

Aims  To compare patient–provider differences in diabetes-related perceptions between African-American and White patients and to examine its association with self-care behaviours. Methods  One hundred and thirty patient–provider pairs were recruited from the greater Detroit area. Patients and providers completed a survey assessing perceptions about diabetes-related concepts and demographic background. The Diabetes Semantic Differential Scale was used to measure diabetes-related perceptions. Patients also reported the frequency of performing self-care behaviours, including following a healthy eating plan, engaging in physical activity, blood glucose monitoring, and taking medication and/or insulin. Results  There were a greater number of patient–provider differences in diabetes-related perceptions for the African-American patients (nine of 18 concepts) compared with the White patients (four of 18 concepts). Stepwise regression analyses found patients’ semantic differential scores to be significantly associated with five self-care behaviours for African-American patients and two self-care behaviours for White patients. Providers’ semantic differential scores emerged as predictors of self-care behaviours for African-American patients, but not for White patients. Conclusions  Our findings suggest that compared with White patients, African-Americans differ in a greater number of diabetes-related perceptions than their providers. Patients’ and providers’ perceptions of diabetes care concepts have a significant impact on a greater number of self-care behaviours for African-American patients than White patients. Diabet. Med. 25, 341–348 (2008)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72171/1/j.1464-5491.2007.02371.x.pd