Does the Duration of Type 2 Diabetes Correlate with Changes in Taste Deficits?

The loss of insulin sensitivity in Type 2 diabetes interferes with cellular utilization of glucose. The underlying down-regulation of insulin receptors and the resulting insulin resistance is wide-spread throughout the body. The cardiovascular consequences may be indirectly responsible for decreased taste sensitivity because of diminished perfusion of the taste buds in this patient population. This study utilized an inexpensive, non-invasive technique, electrogustometry, to directly stimulate the taste buds by applying a variable, direct-current stimulus to measure taste receptor thresholds in newly-diagnosed ( \u3c 2 years) and long-standing diagnosed (\u3e 6 years) male and female Type 2 diabetes mellitus subjects. Taste thresholds were elicited by application of an anodal current to the taste receptors. An increased taste threshold to the anodal current, indicative of a loss of taste sensitivity, was detected in those Type 2 diabetes mellitus subjects with long-standing disease compared to newly diagnosed subjects. Although the differences were not statistically significant a consistent trend suggestive of a significant difference was demonstrated. The results of this pilot study suggest that a future study utilizing a larger number of subjects may result in statistical significance of this approach to managing these two groups

Facilitating factors in cultivating diverse online communities of practice:a case of international teaching assistants during the COVID-19 crisis

Purpose: This study aims to identify facilitating factors in cultivating a linguistically and culturally diverse virtual Community of Practice (CoP) and techniques in tailoring such support for international graduate teaching assistants (ITAs) at a US university while assessing indications for ITAs' self-perceptions in four key areas: social connectedness, confidence teaching in English, pedagogical support and self-efficacy in teaching. Design/methodology/approach: This mixed-methods case study qualitatively analyzes open-ended responses utilizing a Grounded Action Research approach along with follow-up interviews of ITAs. Quantitative measures of key perception areas between three “Experience Groups” were conducted to identify potential correlations with involvement in the CoP. Findings: Calculations using the Kruskal–Wallis test of differences yielded no statistically significant results. However, qualitative analyses highlight ITAs' needs, classified into four general concepts and 16 specific core categories. Evaluation of CoP communications suggests COVID-19 and a sudden transition to online teaching represented recognizable shared problems that invigorated the CoP and overshadowed diversity-related factors. Research limitations/implications: These findings have implications for culturally and linguistically diverse CoPs and particularly for ITA training programs worldwide, allowing universities to enhance support of ITAs and bolster development of undergraduate programs especially during times of crisis and transitions to online learning. Originality/value: The first study to investigate an international, multilingual ITA population in a virtual CoP regardless of academic discipline, this contributes by addressing several common CoP criticisms, including cultivation in distributed contexts and in further guiding expectations for its adoption into culturally and linguistically diverse communities. © 2020, Emerald Publishing Limited

Acoustic microbubble trapping in blood mimicking fluid

Microbubble (MB) volumetric pulsations can be selectively seeded with external ultrasonic fields. The therapeutic use of this phenomenon encompass mechanical thrombolysis and targeted drug deliveries through sonoporating endothelial cells. However, expected outcomes are still plagued by low bubble concentrations and short circulation time after administration. MBs preferentially flow along the centerline of large vessels which deteriorates biological targeting methodology in the case of vascular disease treatment with MBs. Simultaneous MB imaging and trapping against high flow rates has been recently proposed by instantaneously switching optimized ultrasonic beams. Principles were previously validated by circulating MBs with purified water through a flow phantom. But differences between blood and water call for preliminary investigations with blood mimicking fluid (BMF). This study demonstrated the capability of trapping bubbles in BMF with the acoustic trap but with nearly 40% efficiency reduction over the control in water, being present by the suppressed increase of image brightness

Elevation resolution enhancement in 3D photoacoustic imaging using FDMAS beamforming

Photoacoustic imaging is a non-invasive and non-ionizing imaging technique that combines the spectral selectivity of laser excitation with the high resolution of ultrasound imaging. It is possible to identity the vascular structure of the cancerous tissue using this imaging modality. However, elevation and lateral resolution of photoacoustic imaging is usually poor for imaging target. In this study, three dimension filter delay multiply and sum beamforming technique (FDMAS(3D)) is used to improve the resolution and enhance the signal to noise ratio (SNR) of the 3D photoacoustic image that is created by using linear array transducer. This beamforming technique showed improvement in the elevation by 36% when its compared with three dimension delay and sum beamforming technique (DAS(3D)). In addition, it enhanced the SNR by 13 dB compared with DAS (3D)

Simultaneous trapping and imaging of microbubbles at clinically relevant flow rates

Mechanisms for non-invasive target drug delivery using microbubbles and ultrasound have attracted growing interest. Microbubbles can be loaded with a therapeutic payload and tracked via ultrasound imaging to selectively release their payload at ultrasound-targeted locations. In this study, an ultrasonic trapping method is proposed for simultaneously imaging and controlling the location of microbubbles in flow by using acoustic radiation force. Targeted drug delivery methods are expected to benefit from the use of the ultrasonic trap, since trapping will increase the MB concentration at a desired location in human body. The ultrasonic trap was generated by using an ultrasound research system UARP II and a linear array transducer. The trap was designed asymmetrically to produces a weaker radiation force at the inlet of the trap to further facilitate microbubble entrance. A pulse sequence was generated that can switch between a long duration trapping waveform and short duration imaging waveform. High frame rate plane wave imaging was chosen for monitoring trapped microbubbles at 1 kHz. The working principle of the ultrasonic trap was explained and demonstrated in an ultrasound phantom by injecting SonoVue microbubbles flowing at 80 mL/min flow rate in a 3.5 mm diameter vessel

Monitoring Needle Biopsy of Sentinel Lymph Nodes Using Photoacoustic Image with Dynamic-FDMAS Beamformer

As a part of the diagnosis pathway for breast cancer, a needle biopsy of the sentinel lymph node (SLN) is taken for analysis. Photoacoustic imaging is a better approach for guiding a needle than ultrasound imaging. However, the photoacoustic image will be affected by clutter, phase aberration and artefact from the needle. In this study, a dynamic filter delay multiply and sum (D-FDMAS) beamformer was produced to reduce these effects and improve the SNR and contrast difference (CD) of imaging targets. The D-FDMAS beamformer with a sub-group of 16 elements (16 D-FDMAS) showed improvement in SNR of needle and inclusion (SLN) by 8.38 dB and 5.42 dB compared with the delay and sum (DAS) beamfomer. It also showed reduction in CD between the inclusion and needle by almost 12 dB compared with the filter delay multiply and sum (FDMAS) beamformer

High-Power Gallium Nitride HIFU Transmitter with Integrated Real-Time Current and Voltage Measurement

High-Intensity Focused Ultrasound (HIFU) therapy provides a non-invasive technique with which to destroy cancerous tissue without using ionizing radiation. To drive large single-element HIFU transducers, ultrasound transmitters capable of delivering high powers at relevant frequencies are required. The acoustic power delivered to a transducers focal region will determine the treated area, and due to safety concerns and intervening layers of attenuation, control of this output power is critical. A typical setup involves large inefficient linear power amplifiers to drive the transducer. Switched mode transmitters allow for a more compact drive system with higher efficiencies, with multi-level transmitters allowing control over the output power. Real-time monitoring of power delivered can avoid damage to the transducer and injury to patients due to over treatment, and allow for precise control over the output power. This study demonstrates a transformer-less, high power switched mode transmit transmitter based on Gallium-Nitride (GaN) transistors that is capable of delivering peak powers up to 1.8 kW at up to 600 Vpp, while operating at frequencies from DC to 5 MHz. The design includes a 12 bit 16 MHz floating Current/Voltage (I-V) measurement circuit to allow real-time high-side monitoring of the power delivered to the transducer allowing use with multi-element transducers

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured