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The detection, identification, and localization of illicit radiological and nuclear material continue to be key components of nuclear non-proliferation and nuclear security efforts around the world. Networks of radiation detectors deployed at strategic locations in urban environments have the potential to provide continuous radiological/nuclear (R/N) surveillance and provide high probabilities of intercepting threat sources. The integration of contextual information from sensors such as video, Lidar, and meteorological sensors can provide significantly enhanced situational awareness, and improved detection and localization performance through the fusion of the radiological and contextual data. In this work, we present details of our work to establish a city-scale multi-sensor network testbed for intelligent, adaptive R/N detection in urban environments, and develop new techniques that enable city-scale source detection, localization, and tracking.

Radiological source search is a challenging task involving detection and identification of weak sources in a constantly changing radiological background. As of now, many radiological source detection algorithms have been proposed; however, their computational complexity and, hence, reliance on power intensive processing units inhibit low-power applications of radiological source search systems. In this work, we introduce the anomaly filter (AF) algorithm; a computationally light, yet effective time-series source detection algorithm based on exponential weighted moving average (EWMA) and Poisson deviance statistics. Then, we demonstrate that the proposed algorithm can be used in ensemble with other more computationally intensive source detection and identification algorithms to achieve both increased detection performance and reduced power consumption. The proposed AF algorithm and the ensemble algorithms were thoroughly benchmarked against several existing source detection and identification algorithms. The results show that the AF algorithm outperforms existing conventional source detection algorithms, and the ensemble approach improves the overall performance of existing source detection and isotope identification algorithms. Furthermore, the AF algorithm and the non-negative matrix factorization approach-based source identification (NMF-ID) algorithm were combined and implemented on a single-board microcontroller, and the power consumption was measured. This ensemble algorithm reduced the power consumption of the NMF-ID algorithm almost by a factor of 100, while improving the detection performance of the overall system.

The Majorana Demonstrator comprises two arrays of high-purity germanium detectors constructed to search for neutrinoless double-beta decay in 76Ge and other physics beyond the Standard Model. Its readout electronics were designed to have low electronic noise, and radioactive backgrounds were minimized by using low-mass components and low-radioactivity materials near the detectors. This paper provides a description of all components of the Majorana Demonstrator readout electronics, spanning the front-end electronics and internal cabling, back-end electronics, digitizer, and power supplies, along with the grounding scheme. The spectroscopic performance achieved with these readout electronics is also demonstrated.

Networked detector systems can be deployed in urban environments to aid in the detection and localization of radiological and/or nuclear material. However, effectively responding to and interpreting a radiological alarm using spectroscopic data alone may be hampered by a lack of situational awareness, particularly in complex environments. This study investigates the use of Light Detection and Ranging (LiDAR) and streaming video to enable real-time object detection and tracking, and the fusion of this tracking information with radiological data for the purposes of enhanced situational awareness and increased detection sensitivity. This work presents an object detection, tracking, and novel source-object attribution analysis that is capable of operating in real time. By implementing this analysis pipeline on a custom-developed system that comprises a static 2 in. \times 4 in. \times16 in. NaI(Tl) detector colocated with a 64-beam LiDAR and four monocular cameras, we demonstrate the ability to accurately correlate trajectories from tracked objects to spectroscopic gamma-ray data in real time and use physics-based models to reliably discriminate between source-carrying and nonsource-carrying objects. In this work, we describe our approach in detail and present a quantitative performance assessment that characterizes the source-object attribution capabilities of both video and LiDAR. Additionally, we demonstrate the ability to simultaneously track pedestrians and vehicles in a mock urban environment and use this tracking information to improve both detection sensitivity and situational awareness using our contextual-radiological data fusion methodology.

We present an experimental demonstration of additive point source localization (APSL), a sparse parametric imaging algorithm that reconstructs the 3-D positions and activities of multiple gamma-ray point sources. Using a handheld gamma-ray detector array and up to four 8 mu Ci 137Cs gamma-ray sources, we performed both source-search and source-separation experiments in an indoor laboratory environment. In the majority of the source-search measurements, APSL reconstructed the correct number of sources with position accuracies of 20 cm and activity accuracies (unsigned) of 20%, given measurement times of 2 to 3 min and distances of closest approach (to any source) of 20 cm. In source-separation measurements where the detector could be moved freely about the environment, APSL was able to resolve two sources separated by 75 cm or more given only 60 s of measurement time. In these source-separation measurements, APSL produced larger total activity errors of 40%, but obtained source-separation distances accurate to within 15 cm. We also compare our APSL results against traditional maximum likelihood-expectation maximization (ML-EM) reconstructions and demonstrate improved image accuracy and interpretability using APSL over ML-EM. These results indicate that APSL is capable of accurately reconstructing gamma-ray source positions and activities using measurements from existing detector hardware.

Radiological source search is a challenge involving the detection, identification, and localization of weak sources within background environments that vary both spatially and temporally. In this paper, a method for simultaneously detecting and identifying gamma-ray sources using background models formed from spectral data is described. Non-negative matrix factorization (NMF) is used to generate low-dimensional representations of gamma-ray spectra, allowing for a compact means of capturing variation in gamma-ray backgrounds. Background models formed using NMF are used to perform anomaly detection, and additionally, models are augmented with spectral templates of gamma-ray sources to perform simultaneous detection and identification using a likelihood ratio test. The NMF-based detection and identification algorithm is benchmarked against a standard Region of Interest algorithm and shows significant performance gains. In addition, NMF-based anomaly detection shows improvements over methods based on gross counts or principal component analysis. Algorithm performance is evaluated using unshielded sources with activities between 5 and 400 {\mu } Ci at a standoff distance of 20 m using source injection on background data collected using a 1 m2 NaI array on the Radiological Multisensor Analysis Platform.

The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-β decay in ^{76}Ge. The Majorana Demonstrator comprises 44.1 kg of Ge detectors (29.7 kg enriched in ^{76}Ge) split between two modules contained in a low background shield at the Sanford Underground Research Facility in Lead, South Dakota. Here we present results from data taken during construction, commissioning, and the start of full operations. We achieve unprecedented energy resolution of 2.5 keV FWHM at Q_{ββ} and a very low background with no observed candidate events in 9.95 kg yr of enriched Ge exposure, resulting in a lower limit on the half-life of 1.9×10^{25}  yr (90% C.L.). This result constrains the effective Majorana neutrino mass to below 240-520 meV, depending on the matrix elements used. In our experimental configuration with the lowest background, the background is 4.0_{-2.5}^{+3.1}  counts/(FWHM t yr).

The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-β decay in ^{76}Ge. The Majorana Demonstrator comprises 44.1 kg of Ge detectors (29.7 kg enriched in ^{76}Ge) split between two modules contained in a low background shield at the Sanford Underground Research Facility in Lead, South Dakota. Here we present results from data taken during construction, commissioning, and the start of full operations. We achieve unprecedented energy resolution of 2.5 keV FWHM at Q_{ββ} and a very low background with no observed candidate events in 9.95 kg yr of enriched Ge exposure, resulting in a lower limit on the half-life of 1.9×10^{25}  yr (90% C.L.). This result constrains the effective Majorana neutrino mass to below 240-520 meV, depending on the matrix elements used. In our experimental configuration with the lowest background, the background is 4.0_{-2.5}^{+3.1}  counts/(FWHM t yr).

The observation of neutrinoless double-beta decay (0νββ) would show that lepton number is violated, reveal that neu-trinos are Majorana particles, and provide information on neutrino mass. A discovery-capable experiment covering the inverted ordering region, with effective Majorana neutrino masses of 15 - 50 meV, will require a tonne-scale experiment with excellent energy resolution and extremely low backgrounds, at the level of ∼0.1 count /(FWHM·t·yr) in the region of the signal. The current generation 76Ge experiments GERDA and the Majorana Demonstrator, utilizing high purity Germanium detectors with an intrinsic energy resolution of 0.12%, have achieved the lowest backgrounds by over an order of magnitude in the 0νββ signal region of all 0νββ experiments. Building on this success, the LEGEND collaboration has been formed to pursue a tonne-scale 76Ge experiment. The collaboration aims to develop a phased 0νββ experimental program with discovery potential at a half-life approaching or at 1028 years, using existing resources as appropriate to expedite physics results.

We have characterized, for the first time, an n-type segmented inverted coaxial point-contact detector. This novel detector technology relies on a large variation in drift time of the majority charge carriers, as well as image and net charges observed on the segments, to achieve a potential γ-ray interaction position resolution of better than 1 mm. However, the intrinsic energy resolution in this detector is poor (more than 20 keV at 1332 keV) because of charge (electron) trapping effects. We propose an algorithm that enables restoration of the resolution to a value of 3.44 ± 0.03 keV at 1332 keV for events with a single interaction. The algorithm is based on a measurement of the azimuthal angle and the electron drift time of a given event; the energy of the event is corrected as a function of these two values.

The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross section is by far the largest of all low-energy neutrino couplings. This mode of interaction offers new opportunities to study neutrino properties and leads to a miniaturization of detector size, with potential technological applications. We observed this process at a 6.7σ confidence level, using a low-background, 14.6-kilogram CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source at Oak Ridge National Laboratory. Characteristic signatures in energy and time, predicted by the standard model for this process, were observed in high signal-to-background conditions. Improved constraints on nonstandard neutrino interactions with quarks are derived from this initial data set.

This analysis uses source injection into background data collected by the Radiological Multi-sensor Analysis Platform (RadMAP) to characterize the performance of the Poisson Clutter Split algorithm and compare it with a region-of-interest algorithm. This comparison is performed for varying detector array sizes and false alarm rates using data from Sodium Iodide and High Purity Germanium detector arrays. The application of the Poisson Clutter Split algorithm is found to yield significant performance gains for both medium- and high-resolution detector arrays. Furthermore, trade-offs between energy resolution, array size, cost, and detection performance are explored. In doing so, it is shown that the choice of detection algorithm is a key factor in determining the overall system performance and should be an important consideration in system design.

BACKGROUND: Randomized controlled trials (RCTs) often have more than one primary outcome and frequently have secondary and harm outcomes. Comparison of outcomes between study arms is the primary focus of RCTs, but there are times when the relation between outcomes is important, such as determining whether an intermediate outcome and a clinical outcome have a strong association. We sought to determine how often reports of RCTs depict the relations among outcomes at the individual patient level and, for those studies that use composite outcomes, how often the relations between component elements are depicted. METHODS: We selected 20 general, specialty and subspecialty medical journals with high impact factors that publish original clinical research. We identified every RCT in the 2011 and 2012 issues and randomly selected 10 articles per journal. For each article we recorded the number of outcomes, the number of composite outcomes and how often the relations between outcomes or elements of composite outcomes were portrayed. RESULTS: All but 16 of the 200 RCTs had more than one outcome. Thus, outcomes could have been related in 92% of studies, but such relations were only reported in 2 (1%). A total of 33 (17%) investigations measured a composite outcome, 32 of which showed data for each component. None, however, showed cross-tabulation of the components. CONCLUSIONS: Readers are rarely shown the relation between outcomes. Mandatory posting of datasets or requirements for detailed appendices would allow readers to see these cross-tabulations, helping future investigators know which outcomes are redundant, which provide unique information and which are most responsive to changes in the independent variables. While not every relationship between outcomes requires depiction, at present such information is seldom portrayed.

A low-background, high-purity germanium detector has been used to search forevidence of low-energy, bremsstrahlung-generated solar axions. An upper boundof $1.36\times 10^{-11}$ $(95% CL)$ is placed on the direct coupling of DFSZmodel axions to electrons. The prospects for the sensitivity of the MajoranaDemonstrator array of point-contact germanium detectors to solar axions arediscussed in the context of the model-independent annual modulation due to theseasonal variation of the earth-sun distance.

The Majorana Collaboration is building the Majorana Demonstrator, a 60 kg array of high purity germanium detectors housed in an ultra-low background shield at the Sanford Underground Laboratory in Lead, SD. The Majorana Demonstrator will search for neutrinoless double-beta decay of 76Ge while demonstrating the feasibility of a tonne-scale experiment. It may also carry out a dark matter search in the 110 GeV/c2 mass range. We have found that customized Broad Energy Germanium (BEGe) detectors produced by Canberra have several desirable features for a neutrinoless double-beta decay experiment, including low electronic noise, excellent pulse shape analysis capabilities, and simple fabrication. We have deployed a customized BEGe, the Majorana Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and shield at the Kimballton Underground Research Facility in Virginia. This paper will focus on the detector characteristics and measurements that can be performed with such a radiation detector in a low-background environment. © 2010 Elsevier B.V.

Neutrinoless double-beta decay experiments can potentially determine theMajorana or Dirac nature of the neutrino, and aid in understanding the neutrinoabsolute mass scale and hierarchy. Future 76Ge-based searches target ahalf-life sensitivity of >10^27 y to explore the inverted neutrino masshierarchy. Reaching this sensitivity will require a background rate of ~5200 mwe is required for atonne-scale experiment with a compact shield similar to the planned 40-kgMAJORANA DEMONSTRATOR. The required overburden is highly dependent on thechosen shielding configuration and could be relaxed significantly if, forexample, a liquid cryogen and water shield, or an active neutron shield wereemployed. Operation of the MAJORANA DEMONSTRATOR and GERDA detectors will serveto reduce the uncertainties on cosmic-ray background rates and will impact thechoice of shielding style and location for a future tonne-scale experiment. 4/2013: The peer review process revealed that one of the veto rejectionfactors (the factor-of-4 described on p12) needs to be better established. Ourreevaluation of this parameter to date has not yielded strong support for thevalue stated in the manuscript, and we require further study to develop a solidestimate. This further study will supersede the work described in thismanuscript, and may or may not lead to the same conclusion regarding the ~>5200mwe requirement for future tonne-scale 76Ge neutrinoless double beta decayexperiments.

The following principles of appropriate antibiotic use for adults with acute bronchitis apply to immunocompetent adults without complicating comorbid conditions, such as chronic lung or heart disease. The evaluation of adults with an acute cough illness or a presumptive diagnosis of uncomplicated acute bronchitis should focus on ruling out serious illness, particularly pneumonia. In healthy, nonelderly adults, pneumonia is uncommon in the absence of vital sign abnormalities or asymmetrical lung sounds, and chest radiography is usually not indicated. In patients with cough lasting 3 weeks or longer, chest radiography may be warranted in the absence of other known causes. Routine antibiotic treatment of uncomplicated acute bronchitis is not recommended, regardless of duration of cough. If pertussis infection is suspected (an unusual circumstance), a diagnostic test should be performed and antimicrobial therapy initiated. Patient satisfaction with care for acute bronchitis depends most on physician--patient communication rather than on antibiotic treatment.

While the National Health Education Standards focused interest and attention on student (consumer) health literacy, equal attention should be given to teacher (provider) health literacy. Teacher health literacy may be defined as 'the capacity of teachers to obtain, interpret, and understand basic health information and services, with the competence to use such information and services in ways that enhance the learning of health concepts and skills by school students.' This paper reviews a traditional model for school health teacher preparation, then presents an alternative, university field-tested model for enhancing health literacy in teacher education. This new model presents an innovative instructional paradigm, the Child and Adolescent Health (CAH) Logic Framework. This training model (vision) illustrates and emphasizes the link between child and adolescent health research and theory, CAH information, and application to health education, public policy, medical care, and health advocacy. [ABSTRACT FROM AUTHOR]

OBJECTIVE. To assess the ability of the NEXUS II head trauma decision instrument to identify patients with clinically important intracranial injury (ICI) from among children with blunt head trauma.METHODS. An analysis was conducted of the pediatric cohort involved in the derivation set of National Emergency X-Radiography Utilization Study II (NEXUS II), a prospective, observational, multicenter study of all patients who had blunt head trauma and underwent cranial computed tomography (CT) imaging at 1 of 21 emergency departments. We determined the test performance characteristics of the 8-variable NEXUS II decision instrument, derived from the entire NEXUS II cohort, in the pediatric cohort (0-18 years of age), as well as in the very young children (<3 years). Clinically important ICI was defined as ICI that required neurosurgical intervention (craniotomy, intracranial pressure monitoring, or mechanical ventilation) or was likely to be associated with significant long-term neurologic impairment.RESULTS. NEXUS II enrolled 1666 children, 138 (8.3%) of whom had clinically important ICI. The decision instrument correctly identified 136 of the 138 cases and classified 230 as low risk. A total of 309 children were younger than 3 years, among whom 25 had ICI. The decision instrument identified all 25 cases of clinically important ICI in this subgroup.CONCLUSIONS. The decision instrument derived in the large NEXUS II cohort performed with similarly high sensitivity among the subgroup of children who were included in this study. Clinically important ICI were rare in children who did not exhibit at least 1 of the NEXUS II risk criteria. [ABSTRACT FROM AUTHOR]

We propose a complete framework for Bayesian image reconstruction and uncertainty quantification based on a Gaussian process prior (GPP) to overcome limitations of maximum likelihood expectation maximization (ML-EM) image reconstruction algorithm. The prior distribution is constructed with a zero-mean Gaussian process (GP) with a choice of a covariance function, and a link function is used to map the Gaussian process to an image. Unlike many other maximum a posteriori approaches, our method offers highly interpretable hyperparamters that are selected automatically with the empirical Bayes method. Furthermore, the GP covariance function can be modified to incorporate a priori structural priors, enabling multi-modality imaging or contextual data fusion. Lastly, we illustrate that our approach lends itself to Bayesian uncertainty quantification techniques, such as the preconditioned Crank-Nicolson method and the Laplace approximation. The proposed framework is general and can be employed in most radiation image reconstruction problems, and we demonstrate it with simulated free-moving single detector radiation source imaging scenarios. We compare the reconstruction results from GPP and ML-EM, and show that the proposed method can significantly improve the image quality over ML-EM, all the while providing greater understanding of the source distribution via the uncertainty quantification capability. Furthermore, significant improvement of the image quality by incorporating a structural prior is illustrated., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Competing Interests: The authors declare no conflicts of interest.

Background: Traumatic brain injuries involving the posterior fossa are rare and case reports indicate they often result in severe outcomes. We seek to describe characteristics and outcomes of traumatic posterior fossa injuries., Methods: We performed a planned secondary analysis of all patients with posterior fossa injuries enrolled in the NEXUS head computed tomography (CT) validation study dataset. The dataset includes prospectively collected data on all patients undergoing non-contrast cranial CT following blunt traumatic head injury from April 2006 to December 2015, at four emergency departments comprising community and university sites, as well as urban, suburban and rural settings in California (Antelope Valley Hospital, San Francisco General Hospital, UCLA Ronald Reagan Medical Center, UCSF Fresno Community Regional Medical Center). We classified each patient into one of three injury patterns: Type I-notable traumatic injuries primarily above the tentorium, with minimal posterior fossa involvement; Type II-notable traumatic injuries both above and within the posterior fossa; and Type III-notable traumatic injuries primarily within the posterior fossa. We extracted demographic data for each patient as well as physician assessments of the NEXUS head CT and Canadian Head CT rule clinical criteria, mechanisms of injury, patient outcomes, and the location and types of intracranial injuries sustained., Findings: Of 11,770 patients in the database, 184 (1.6%) had posterior fossa injuries on CT imaging. Mean age was 55.4 years (standard deviation 22.5 years, range 2-96 years); 131 (71.2%) were males. We identified 63 patients with Type I injuries, 87 with Type II injuries, and 34 Type III injuries. The most common mechanisms of injury were falls (41%), pedestrian vs automobile (15%), and motor vehicle collisions (13%). On presentation most patients had altered mental status (72%), abnormal behavior (53%), or a neurologic deficit (55%). The majority of individuals, 151 (82%), had clinically important injuries and 111 (60%) required neurosurgical intervention. The dispositions for the subjects included 52 deaths (28%), 49 (27%) patients discharged home, and 48 (26%) discharged to rehabilitation facilities. When compared to individuals with Type I and Type II injuries, patients with Type III injuries had lower mortality (6% vs 30% and 35%) and higher percentage of patients discharged home (60% vs 19% and 21%)., Interpretation: Patients with Type I and II injury patterns (those that involve both the posterior fossa and supratentorium) experienced high mortality and disability. Patients with Type III injuries (isolated posterior fossa) had a better prognosis., Funding: None., Competing Interests: None of the authors have any conflicts of interest related to this research database or analysis. Richelle J. Cooper receives support grant funding from PCORI, NHLBI, and NINDS. She has received honoraria for speaking at the American College of Emergency Physicians Scientific Assembly Editor's Forum, and support for attending the American College of Emergency Physicians Scientific Assembly. In addition, she receives a stipend from the American College of Emergency Physicians for her roles as Executive Deputy Editor, and as Methodology and Statistics editor at Annals of Emergency Medicine. Gregory W. Hendey receiving NHLBI grant funding to UCLA for Prevention and Early Treatment of Acute Lung Injury (PETAL) network. William R. Mower has received grants or contracts from NIH, CDC. In addition, he has received medicolegal consulting fees., (© 2024 The Author(s).)

Purpose: Trailing-edge populations at the low-latitude, receding edge of a shifting range face high extinction risk from climate change unless they are able to track optimal environmental conditions through dispersal., Methods: We fit dispersal models to the locations of 3165 individually-marked black-throated blue warblers (Setophaga caerulescens) in the southern Appalachian Mountains in North Carolina, USA from 2002 to 2023. Black-throated blue warbler breeding abundance in this population has remained relatively stable at colder and wetter areas at higher elevations but has declined at warmer and drier areas at lower elevations., Results: Median dispersal distance of young warblers was 917 m (range 23-3200 m), and dispersal tended to be directed away from warm and dry locations. In contrast, adults exhibited strong site fidelity between breeding seasons and rarely dispersed more than 100 m (range 10-1300 m). Consequently, adult dispersal kernels were much more compact and symmetric than natal dispersal kernels, suggesting adult dispersal is unlikely a driving force of declines in this population., Conclusion: Our findings suggest that directional natal dispersal may mitigate fitness costs for trailing-edge populations by allowing individuals to track changing climate and avoid warming conditions at warm-edge range boundaries., (© 2024. The Author(s).)