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The Single Volume Scatter Camera (SVSC) Collaboration aims to develop portable neutron imaging systems for a variety of applications in nuclear non-proliferation. Conventional double-scatter neutron imagers are composed of several separate detector volumes organized in at least two planes. A neutron must scatter in two of these detector volumes for its initial trajectory to be reconstructed. As such, these systems typically have a large footprint and poor geometric efficiency. We report on the design and characterization of a prototype monolithic neutron scatter camera that is intended to significantly improve upon the geometrical shortcomings of conventional neutron cameras. The detector consists of a 50 mm×56 mm× 60 mm monolithic block of EJ-204 plastic scintillator instrumented on two faces with arrays of 64 Hamamatsu S13360-6075PE silicon photomultipliers (SiPMs). The electronic crosstalk is limited to < 5% between adjacent channels and < 0.1% between all other channel pairs. SiPMs introduce a significantly elevated dark count rate over PMTs, as well as correlated noise from after-pulsing and optical crosstalk. In this article, we characterize the dark count rate and optical crosstalk and present a modified event reconstruction likelihood function that accounts for them. We find that the average dark count rate per SiPM is 4.3 MHz with a standard deviation of 1.5 MHz among devices. The analysis method we employ to measure internal optical crosstalk also naturally yields the mean and width of the single-electron pulse height. We calculate separate contributions to the width of the single-electron pulse-height from electronic noise and avalanche fluctuations. We demonstrate a timing resolution for a single-photon pulse to be (128 ± 4) ps. Finally, coincidence analysis is employed to measure external (pixel-to-pixel) optical crosstalk. We present a map of the average external crosstalk probability between 2×4 groups of SiPMs, as well as the in-situ timing characteristics extracted from the coincidence analysis. Further work is needed to characterize the performance of the camera at reconstructing single- and double-site interactions, as well as image reconstruction.

Recent 2D hydrothermal modeling efforts published by Pepin et al. (2015) suggest that the low-temperature (~41°C) geothermal system in Truth or Consequences, NM is characterized by deep (2-8 km) groundwater circulation within permeable (10-12 m²) fractured crystalline rocks. Their models were constrained by geochemistry, temperature, flow velocity, and carbon-14 data but lack calibration to aquifer test data. On June 13, 2015, we conducted an aquifer test in a newly drilled 73-meter deep geothermal well within the town's hot-springs district. The production interval of this well is 24 meters long and is within fractured Precambrian metamorphic rocks. We installed pressure transducers in the production well and in two observation wells to monitor water levels during the test. The production rate averaged 1.8 x 10-2 m³/s (283 gpm) and the two observation wells were located 20 and 38 meters away from the production well, respectively. The two observation wells were shallower and completed in Quaternary alluvium. Production well water levels oscillated during the first two minutes of the aquifer test due to inertial effects. Net drawdown in the production well after 97 minutes of pumping was approximately 0.6 meters, while minimal drawdown was evidenced in the observation wells. Applying the Cooper-Jacob model provided a transmissivity estimate of 1.1 x 104 m²/day and thereby a permeability range of 5 x 10-10 to 2 x 10-12 m². These results are further evidence that the crystalline basement rocks within the Rio Grande Rift can be remarkably permeable when significantly fractured. [ABSTRACT FROM AUTHOR]

Objectives: Limited normative reference data are available for validated outcomes of flexible endoscopic evaluation of swallowing (FEES). We aimed to examine healthy swallowing via FEES in community-dwelling healthy adults to derive a preliminary reference dataset of normative validated FEES outcomes to guide clinical interpretation and diagnostic decision-making., Methods: Adults with no history of dysphagia-related disease underwent simultaneous videofluoroscopy and FEES imaging using a standardized 11-item bolus protocol. Trained raters performed duplicate, independent, blinded ratings of the New Zealand Secretion Scale (NZSS), Penetration-Aspiration Scale (PAS), and Dynamic Imaging Grade of Swallowing Toxicity-FEES (DIGEST-FEES) validated scales. Descriptive statistics were performed at the bolus (PAS) and participant level (NZSS, DIGEST-FEES)., Results: 361 swallows from 33 community-dwelling adults (36.6 ± 14.7 years old) were analyzed. In rank order, distribution profiles were: (1) NZSS: 95% normal (NZSS = 0), 5% abnormal (NZSS = 4); (2) Worst PAS: 73% safe (PAS 1-2, n = 24), 21% penetration above the true vocal folds (PAS 3, n = 7), 6% deep penetration to the true vocal folds (PAS = 5, n = 2); (3) DIGEST-FEES Safety Grades: 91% Grade 0 (normal, n = 30), 9% Grade 1 (mild impairment, n = 3); (4) DIGEST-FEES Efficiency Grades: 73% Grade 0 (normal, n = 24), 24% Grade 1 (mild impairment, n = 8), 3% Grade 2 (moderate impairment, n = 1)., Conclusion: This preliminary healthy FEES dataset highlights variation in swallowing safety and efficiency and suggests careful interpretation of FEES outcomes to avoid over-pathologizing impairment. Future studies are warranted to obtain additional normative data in diverse populations to further understand normal variation in FEES outcomes to guide clinically meaningful diagnostic cut-points., Level of Evidence: 3 Laryngoscope, 135:1034-1038, 2025., (© 2024 The Author(s). The Laryngoscope published by Wiley Periodicals LLC on behalf of The American Laryngological, Rhinological and Otological Society, Inc.)

Purpose: Obstructive sleep apnea (OSA) presents perioperative challenges with increased risk for complications. Floppy eyelid syndrome (FES) is associated with OSA yet has not been addressed perioperatively. The current standard for perioperative OSA screening includes assessing patient risk factors or the STOP-BANG tool, which requires an active participant. We aimed to confirm a connection between FES and OSA in presurgical patients and develop a screening method appropriate for patients with perioperative OSA risk., Materials and Methods: 162 presurgical pre-anesthesia clinic patients were enrolled. Screening questions determined eligibility. Those who were pregnant or aged < 19 were excluded. Control group included those with a STOP-BANG score < 3. Experimental group included those with BMI > 35 and OSA diagnosis. Examiners photographed participants' eyes with vertical and horizontal retraction while two blinded ophthalmologists used a grading scale to review grade of eyelid laxity., Results: Differences in habitus, ASA score, and hypertension as a comorbidity were significant. Sensitivity of FES screening was 52% (CI 37-66%) and specificity was 56% (CI 46-66%) for reviewer 1. For reviewer 2, sensitivity was 48% (CI 28-69%) and specificity was 72% (CI 60-81%). Negative predictive value was 86% (CI 81-90) for reviewer 1 and 88% (CI 83-92%) for reviewer 2. Inter-rater agreement was moderate., Conclusion: While specificity and sensitivity were lower than anticipated, negative predictive value was high. Given this strong negative predictive value, our findings indicate using eyelid retraction to screen for FES has perioperative clinical utility. These findings encourage further research addressing the connection of lid laxity/FES to OSA., Key Points: • Aimed to investigate if a FES screening tool could identify perioperative OSA risk. • Negative predictive value for FES with OSA was 86%. • Observing periocular lid laxity has clinical utility; is feasible in any patient., (© 2022. The Author(s).)

Studying the molecular basis of familial renal cell carcinoma (RCC) has allowed identification of novel RCC genes involved in the pathogenesis of both inherited and sporadic RCC. We describe a constitutional balanced t(3;8)(p14;q24.1) translocation found in a brother and sister with bilateral clear cell RCC (CC-RCC) diagnosed in their forties. Consistent with a prior report, we demonstrated by RT-PCR of RNA from lymphoblastoid cells fusion mRNAs derived from the fragile histidine triad (FHIT) at 3p14 and TRC8 at 8q24.1 in both affected siblings. Cytogenetic analysis of a CC-RCC tumor from the affected sister from short-term tumor cell culture showed both diploid and pseudotetraploid populations containing the translocation and normal appearing chromosomes 3 and 8. Fluorescent in situ hybridization using bacterial artificial chromosomes containing sequences from the FHIT and TRC8 genes demonstrated normal FHIT signals and TRC8 signals on nontranslocated chromosomes in the constitutional blood sample, but the TRC8 signal was absent in a subset of diploid and pseudotetraploid cells from the tumor. The tumor also contained a heterozygous VHL frameshift somatic mutation. These results confirm that balanced translocations disrupting the TRC8 and FHIT genes result in an increased genetic susceptibility for bilateral CC-RCC. The presence of diploid and tetraploid tumor cells with and without TRC8 deletions on the nontranslocated chromosome suggest that loss of the remaining normal allele of TRC8 may contribute to tumor development at later stages., ((c) 2007 Wiley-Liss, Inc.)