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Purpose We describe the initial assessment of the peripheral quantitative CT (pQCT) imaging capabilities of a cone-beam CT (CBCT) scanner dedicated to musculoskeletal extremity imaging. The aim is to accurately measure and quantify bone and joint morphology using information automatically acquired with each CBCT scan, thereby reducing the need for a separate pQCT exam. Methods A prototype CBCT scanner providing isotropic, sub-millimeter spatial resolution and soft-tissue contrast resolution comparable or superior to standard multi-detector CT (MDCT) has been developed for extremity imaging, including the capability for weight-bearing exams and multi-mode (radiography, fluoroscopy, and volumetric) imaging. Assessment of pQCT performance included measurement of bone mineral density (BMD), morphometric parameters of subchondral bone architecture, and joint space analysis. Measurements employed phantoms, cadavers, and patients from an ongoing pilot study imaged with the CBCT prototype (at various acquisition, calibration, and reconstruction techniques) in comparison to MDCT (using pQCT protocols for analysis of BMD) and micro-CT (for analysis of subchondral morphometry). Results The CBCT extremity scanner yielded BMD measurement within ±2–3% error in both phantom studies and cadaver extremity specimens. Subchondral bone architecture (bone volume fraction, trabecular thickness, degree of anisotropy, and structure model index) exhibited good correlation with gold standard micro-CT (error ~5%), surpassing the conventional limitations of spatial resolution in clinical MDCT scanners. Joint space analysis demonstrated the potential for sensitive 3D joint space mapping beyond that of qualitative radiographic scores in application to non-weight-bearing versus weight-bearing lower extremities and assessment of phalangeal joint space integrity in the upper extremities. Conclusion The CBCT extremity scanner demonstrated promising initial results in accurate pQCT analysis from images acquired with each CBCT scan. Future studies will include improved x-ray scatter correction and image reconstruction techniques to further improve accuracy and to correlate pQCT metrics with known pathology.

and spin-selective optical transitions of NV centers form the basis of optically detected magnetic resonance and have fostered a plethora of interest in developing quantum biosensing methods, as exemplified by the nanoscale magnetometry [1e,2a] and spinenhanced ultrasensitive diagnostics. [1a-c] Yet, the achievable sensitivity and temporal resolution are compromised by inefficient photon generation and extraction from excited NV centers owing to their long radiative lifetime, which ranges from 10 to 30 ns depending on the size and refractive index of nanodiamonds.Boosting the efficiency of photon generation hinges on accelerating the spontaneous emission of NV centers. [2c,3] For conventional quantum emitters such as semiconductor quantum dots and organic dyes, their transition dynamics can be modified by the Purcell effect, which is linearly dependent on the quality factor but inversely scales with the mode volume of an optical cavity. [3b,c,4] Owing to the high-Q cavity mode of a dielectric resonator and the subwavelength mode volume of a plasmonic nanocavity, they are both well suited to provide a significant Purcell enhancement to accelerate the transition dynamics of quantum emitters, provided that the optical cavity is tuned to be in resonance with the emission spectrum of quantum emitters. However, as an optical cavity usually supports a much narrower spectral linewidth than the broadband emission spectrum of NV centers, it proves less Nitrogen-vacancy (NV) centers in nanodiamond hold great promise for creating superior biological labels and quantum sensing methods. Yet, inefficient photon generation and extraction from excited NV centers restrict the achievable sensitivity and temporal resolution. Herein, an entirely complementary route featuring pyramidal hyperbolic metasurface is reported to modify the spontaneous emission of NV centers. Fabricated using nanosphere lithography, the metasurface consists of alternatively stacked silica-silver thin films configured in a pyramidal fashion, and supports both spectrally broadband Purcell enhancement and spatially extended intense local fields owing to the hyperbolic dispersion and plasmonic coupling. The enhanced photophysical properties are manifested as a simultaneous amplification to the spontaneous decay rate and emission intensity of NV centers. It is envisioned that the reported pyramidal metasurface can serve as a versatile platform for creating chip-based ultrafast single-photon sources and spin-enhanced quantum biosensing strategies, as well as aid in further fundamental understanding of photoexcited species in condensed phases.

Trichomonas vaginalis (TV) by APTIMA TV on a TIGRIS instrument. Each patient was asked on a scale of one to five to express strength of agreement or disagreement with ease or comfort of the 6 step self collection process for the VSCT. Results There were a total of 22 CT, 19 TV and 2 NG infections with dual infections in 6 people (one CT and NG, one NG and TV and four CT and TV). Prevalences were as follows: CT 3.9% (GYC 1.3% and YHC 12.6%); NG 0.3% (2.0% in YHC); TV 3.4% (GYC 0.4% and YHC 13.4%). Sensitivity for CT infections were CSCT 100%, PC 100%, SP 81.8%; VSCT-self 100%, VSCT-physician 95.4%: for TV infections CSCT 89.4%, PC 84.2%, SP 63.2%; both VSCT 100%: for NG all collections 100%. There were no false positives (% specificity 100). Results of the survey revealed that the majority of patients found opening the package, self sampling, insertion of the SCT swab into preservation media and uncapping and recapping the tube were relatively easy to perform. Eighty two per cent experienced no discomfort using the SCT kit for collection. Conclusions APTIMA testing on the TIGRIS showed that the cervical and vaginal SCT and PC L-Pap samples were 100% sensitive in detecting CT and NG infections. VSCT samples detected all TV infections but cervical SCT and PC L-Pap were less sensitive. SP LPap samples showed reduced sensitivity for CT and TV. Overall, patients were in strong agreement with the ease of use of the VSCT and most found the process comfortable. Objectives To investigate the performance of the Bio-Rad Dx CT/ NG/MG Assay with an internal control for the detection of Chlamydia trachomatis (CT) and Mycoplasma genitalium (MG) in urogenital samples in comparison with the Roche Cobas TaqMan CT test and an in-house TaqMan PCR test for MG. For Neisseria gonorrhoeae (NG), only positive PCR results were controlled by culture. Methods In this prospective study, urogenital samples were obtained from symptomatic and asymptomatic patients attending the STI center of Bordeaux, France, from January to April 2010. For symptomatic women and men, two endocervical swabs and two urethral swabs were collected, respectively. All patients and women collected first-catch urines and two vaginal swabs, respectively. Two swabs per site were used, a flocked swab in the universal transport medium and the Bio-Rad flocked swab in its transport medium. For the Bio-Rad CT/NG/MG assay, the DNA was manually extracted and amplified according to the manufacturer 's instructions. For the comparator PCR tests, DNA was extracted using the MagNa Pure LC instrument (Roche Diagnostics) and amplified with the Cobas TaqMan CT 48 assay (Roche Diagnostics) and with a MgPa-targeted PCR assay on an ABI Prism 7000 (Applied Biosystems) for MG. The patient was considered as infected if at least two of the 4 or 6 PCR tests performed according to the gender and characteristics of patients, were positive. For asymptomatic men, in case of discrepancy, the urine sample was retested by both methods and the patient was considered infected if at least two of the f...

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