Four-Line C*/CH* Optical Sensor for Chemiluminescence Based Imaging of Flame Stoichiometry.

In the present work, an optical sensor was developed and calibrated for the purpose of non-intrusive equivalence ratio measurements in combustion systems. The sensor incorporates a unique four-line, single-sensor chemiluminescence imaging-based approach, which relies on the ratio of C* and CH* radical-species intensities to obtain measurements of equivalence ratios. The advantage of the four-line sensor is the use of additional filtering to mitigate broadband luminescence signals, and its improvements over conventional two-line chemiluminescence diagnostics are discussed.

Safety evaluation of carbon tetrafluoride as an inert hyperbaric breathing gas in Sprague-Dawley rats.

Carbon tetrafluoride (CF) is an inert gas with higher molecular weight and lower water solubility than commonly used hyperbaric breathing gases. These inert gas properties decrease time required to decompress and avoid decompression sickness after deep dives. To assess CF toxicity, Sprague-Dawley rats were exposed to 8 atm absolute (ATA) air (10 males, 10 females) or 8 ATA 79% CF/21% O (25 males, 25 females).

Single-sensor filter-intensified fiber optic 4D tomographic CH* chemiluminesence flame measurements.

Chemiluminesence is one of the most common reacting flow visualization techniques, in which a narrowband wavelength associated with species radicals is captured on an image sensor. This technique can provide key insights into flame physics, particularly when a full 3D field can be extracted. Tomographic imaging can capture 3D instantaneous information, but becomes impractical to use when the technique is extended to larger, heavier high-speed imaging equipment.

Urinary Calcium for Tracking Bone Loss and Kidney Stone Risk in Space.

Urinary calcium (Uca) levels in space reflect bone loss and kidney stone risk and could be measured using portable devices. This project evaluated the repeatability of Uca measurements to assess how many repeated measurements would be needed to detect significant urinary calcium elevations in space. A total of six subjects collected 24-h urine samples weekly for 8 wk and took 500 mg of oral calcium carbonate and 400 IU of vitamin D daily in week 7 and 8.

Ocular changes over 60 min in supine and prone postures.

Some astronauts are returning from long-duration spaceflight with structural ocular and visual changes. We investigated both the transient and sustained effects of changes in the direction of the gravity vector acting on the eye using changes in body posture. Intraocular pressure (IOP; measured by Perkins tonometer), ocular geometry (axial length, corneal thickness, and aqueous depth-noncontact biometer), and the choroid (volume and subfoveal thickness optical coherence tomography) were measured in 10 subjects (5 males and 5 females).

Acute effects of changes to the gravitational vector on the eye.

Intraocular pressure (IOP) initially increases when an individual enters microgravity compared with baseline values when an individual is in a seated position. This has been attributed to a headward fluid shift that increases venous pressures in the head. The change in IOP exceeds changes measured immediately after moving from seated to supine postures on Earth, when a similar fluid shift is produced.

Intranasal Deposition of Accuspray™ Aerosol in Anatomically Correct Models of 2-, 5-, and 12-Year-Old Children.

Background: To our knowledge, quantification of intranasal deposition of aerosol generated by Accuspray(™) (AS) in children has never been published. We hypothesized that deposition would vary significantly with age and with placement of the device within, or outside, of the nostril.

Methods: We tested these hypotheses in anatomically-correct physical models based on CT scans of 2-, 5-, and 12-year-old children with normal, intranasal airways.

Nebulized live-attenuated influenza vaccine provides protection in ferrets at a reduced dose.

Live-attenuated influenza vaccine (LAIV) is delivered to vaccine recipients using a nasal spray syringe. LAIV delivered by this method is immunogenic at current doses; however, improvements in nasal delivery might allow for significant dose reduction. We investigated LAIV vaccination in ferrets using a high efficiency nebulizer designed for nasal delivery.

Laparoscopic surface scanning and subsurface targeting: implications for image-guided laparoscopic liver surgery.

Segmental liver resection and locoregional ablative therapies are dependent upon accurate tumor localization to ensure safety as well as acceptable oncologic results. Because of the liver's limited external landmarks and complex internal anatomy, such tumor localization poses a technical challenge. Image guided therapies (IGT) address this problem by mapping the real-time, intraoperative position of surgical instruments onto preoperative tomographic imaging through a process called registration.

Dual-frequency ultrasound for detecting and sizing bubbles.

ISS construction and Mars exploration require extensive extravehicular activity (EVA), exposing crewmembers to increased decompression sickness risk. Improved bubble detection technologies could help increase EVA efficiency and safety. Creare Inc.