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This paper demonstrates a compressed sensing-based single-shot hyperspectral imaging system for combustion diagnostics. The hyperspectral system can capture well-resolved spectra in a 2D plane through a single shot, i.e., converting a 3D data cube of 2D spatial and 1D spectral information into a compressed 2D hyperspectral image. Experimentally, the light emissions are first coded by a random binary pattern to generate the hyperspectral content, which is then sent through a spectrometer. The resulting compressed hyperspectral image is computationally analyzed to recover original 2D spatial and 1D spectral information. C2∗ and CH∗ chemiluminescence emissions of a methane/air flame at various equivalence ratios are measured using the compressed hyperspectral imaging technique. Comparison to traditional measurements shows good agreement in the correlation of emission ratio to equivalence ratio. The technique can be further applied to other laser-based combustion diagnostics.

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The Multiplexed Structured Image Capture (MUSIC) technique is used to demonstrate single-shot multiframe passive imaging, with a nanosecond difference between the resulting images. This technique uses modulation of light from a scene before imaging, in order to encode the target's temporal evolution into spatial frequency shifts, each of which corresponds to a unique time and results in individual and distinct snapshots. The resulting images correspond to different effective imaging gate times, because of the optical path delays. Computer processing of the multiplexed single-shot image recovers the nanosecond-resolution evolution. The MUSIC technique is used to demonstrate imaging of a laser-induced plasma. Simultaneous single-shot measurements of electron numbers by coherent microwave scattering were obtained and showed good agreement with MUSIC characterization. The MUSIC technique demonstrates spatial modulation of images used for passive imaging. This allows multiple frames to be stacked into a single image. This method could also pave the way for real-time imaging and characterization of ultrafast processes and visualization, as well as general tracking of fast objects.

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In this work, high-speed flame chemiluminescence has been obtained by using the time-multiplexed structured detection (TMSD) imaging method from a single snapshot. TMSD sheers the time lapse into the spatial frequency shifts, which allows multiple high-speed images to be frequency upshifted into distinct spatial frequency regions from the original image. A cumulative exposure captured in a single snapshot image contains distinct time evolution. Each distinct image is demultiplexed and recovered by hyperdyne mixing with the modulation frequency. TMSD is an optical frequency domain analog to carrier frequency modulation in radio and microwave detections. Specifically, a digital micromirror device (DMD) spatially modulates flame chemiluminescence just prior to the camera. Spatial frequency of each distinct image is mixed between the original spatial frequency components and DMD modulation pattern frequency, resulting in a coded snapshot. The high-speed flame chemiluminescence image is recovered by demodulation. TMSD is similar to structured illumination used in super-resolution microscopy, but offers more advantages, for it does not alternate incident illumination light. Since DMDs are available with speeds up to 40 kHz, this technique shows promise as a cost-effective means of high-speed imaging and diagnostics of combustion phenomena.

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Chinese philosophy has been a major cornerstone of Chinese culture for millennia and has bestowed on the world traditions such as Taoism, Yin and Yang, and filial piety. Although these beliefs have remained steadfast over thousands of years, their ability to survive unchanged in the future is uncertain. As the world forges ahead into the 21st century, several pertinent questions arise: Will age-old axioms, primarily those concerning elderly Chinese and their relationship with their children, survive? When ancient, traditional beliefs conflict with newer, Western ideas, which system of thought is likely to be the victor? Moreover, will elderly Chinese Americans and their perceptions concerning long-term care facilities cause problems with the traditional familial unit? This article will discuss these issues in detail.

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OBJECTIVE: To determine the accuracy of reporting of self-monitored blood glucose in pregnant women with diabetes. DESIGN: A descriptive study. Patient-recorded logs of self-monitored blood glucose values were compared to meter memory values. SETTING AND PARTICIPANTS: A convenience sample of 85 pregnant women with pregestational and gestational diabetes enrolled in a perinatal diabetes program in an urban teaching hospital. RESULTS: Accuracy significantly differed by diabetes type (p = .015). Women with type 1 diabetes did not accurately record on average 36.7% of blood glucose values as compared to 8.5% of type 2, 21.2% of GDMA(1) (gestational diabetes mellitus, diet controlled), and 23.4% of GDMA(2) (gestational diabetes mellitus, insulin controlled). Age positively affected accuracy, but accuracy was not affected by marital status, educational background, or duration of diabetes. Statistical significance was shown between values from women with private health insurance and women with Medicaid. Eighty percent of the sample overreported by adding phantom values in the logbook, which did not differ by diabetes type. Approximately 70% underreported by not logging values in the meter memory that was statistically significant by diabetes type. CONCLUSION: Assessment of the reliability of self-monitored blood glucose results from pregnant women with diabetes is recommended owing to a significant degree of falsification.

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