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Since the early 1960s, Israel has used the Dimona reactor in the Negev Desert for unsafeguarded plutonium production. Estimates of cumulative plutonium production have been very uncertain, however,...

Future nuclear arms-control agreements may place numerical limits on items that are difficult to monitor with national technical means, even when complemented with onsite inspections. Such items could include small objects and mobile assets, such as non-deployed nuclear warheads and mobile missile launchers. Typically, this verification task can be addressed with unique identifiers, but standard tagging techniques may be unacceptable in this case due to host concerns about safety and intrusiveness. First proposed in the late 1980s and partially developed by Sandia National Laboratories in the early 1990s, the “Proximity Tag” or “Buddy Tag” concept seeks to overcome these concerns by separating the tag from the treaty accountable item itself. A buddy tag has two key elements: a tamper-indicating enclosure and a motion-detection system designed to detect illicit movements in a stand-down period. As part of this project, we have built a buddy-tag prototype for demonstration and evaluation purposes. This paper reviews the design choices and functionalities of the tag’s motion-detection subsystem. We pursue a modular approach for the tag’s hardware, built around an Arduino-class microcontroller and a non-export-controlled low-noise accelerometer, and use open-source algorithms for the motion-detection software. We discuss the results of an extensive experimental campaign involving both indoor and outdoor measurements assessing the performance of the tag under real-world environmental conditions.

Passive gamma spectroscopy has been successfully used for nuclear warhead inspection systems based on the template-matching approach. The most prominent example of such a system is Sandia’s Trusted...

ZusammenfassungDer Artikel stellt eine Zusammenfassung persönlicher Eindrücke dar, die PhysiotherapeutInnen bei Behandlung von COVID-19-PatientInnen auf der Intensivstation erleben. Es werden seelische und körperliche Eindrücke geschildert und weitere Auswirkungen auf soziale und alltägliche Belange aufgezeigt. Von zentraler Bedeutung sind dabei weniger die Ängste, sondern eher die Sorgen. Die Arbeit mit COVID-19-Patienten zeigt Auswirkungen auf alle Bereich des privaten und beruflichen Umfeldes der KollegInnen.

Researchers have recently proposed a new approach to nuclear-arms-control verification, dubbed “deferred verification.” The concept forgoes inspections at sensitive nuclear sites and of nuc...

BackgroundThe association between benign prostatic hyperplasia (BPH) and prostate cancer (PCa) remains controversial, largely due to inherent detection bias in traditional observational studies. The objective of this study is to assess their association using inherited SNPs.MethodsSubjects were White men from the large population-based UK Biobank (UKB). Association between BPH and PCa was tested: 1) phenotypical correlation using chi-square test, 2) genetic correlation (rg) based on 1,126,841 polymorphic SNPs across the genome using linkage disequilibrium score regression (LDSR), and 3) cross-disease genetic associations based on known risk-associated SNPs (15 for BPH and 239 for PCa), individually and cumulatively as measured by genetic risk score (GRS).FindingsAmong 214,717 White men in the UKB, 24,623 (11.47%) and 14,311 (6.67%) had a diagnosis of BPH and PCa, respectively. Diagnoses of these two diseases were significantly correlated, χ2=1862.80, Prg (95% confidence interval (CI))=0.27 (0.15-0.39), P=9.17E-06. In addition, significant cross-disease genetic associations for established risk-associated SNPs were also found. Among the 250 established GWAS-significant SNPs of PCa or BPH, 51 were significantly associated with risk of the other disease at PP=3.04E-7 (χ2-test). Furthermore, significant cross-disease GRS associations were also found; GRSBPH was significantly associated with PCa risk (odds ratio (OR)=1.26 (1.18-1.36), P=1.62E-10), and GRSPCa was significantly associated with BPH risk (OR=1.03 (1.02-1.04), P=8.57E-06). Moreover, GRSBPH was significantly and inversely associated with lethal PCa risk in a PCa case-case analysis (OR=0.58 (0.41-0.81), P=1.57E-03). In contrast, GRSPCa was not significantly associated with lethal PCa (OR=0.99 (0.94-1.04), P=0.79).InterpretationBPH and PCa share common inherited genetics which suggests the phenotypical association of these two diseases in observational studies is not entirely caused by detection bias. This novel finding may have implications in disease etiology and risk stratification.FundingNone.

Future arms control treaties may place limits on the total number of warheads in the arsenals of weapon states, which would introduce qualitatively new verification objectives, including confirming numerical limits on declared nuclear warheads and confirming the authenticity of nuclear warheads prior to dismantlement. Meeting these objectives would require on-site inspections at new types of facilities, including warhead storage sites, which could put at risk highly sensitive information both related to military operations and warhead design. Weapon states may be reluctant to consider some of the anticipated procedures. As a way to address this challenge, in this paper, we examine the potential of verification approaches that emphasize non-intrusiveness from the outset. Relevant examples include innovative tagging approaches and hashed declarations to confirm the correctness of warhead declarations and novel types of inspection systems to confirm the authenticity of nuclear warheads, while satisfying the different and sometimes conflicting requirements by the host and the inspector. New international R&D efforts could usefully focus on non-intrusive technologies and approaches, which may show more promise for early demonstration and adoption. If demonstrated, such non-intrusive verification approaches could be particularly important for moving forward discussions about expanding the scope of current agreements and facilitating discussions with weapon states that have so far not been part of formal nuclear arms control agreements.

Several nuclear archaeology techniques have been proposed to determine historic plutonium production in dedicated nuclear reactors. These methods rely on sampling materials from the reactor core, o...

Information barriers are trusted measurement systems to confirm the authenticity of nuclear warheads based on their radiation signatures. Traditional inspection systems rely on complex electronics both for data acquisition and processing. Several research efforts have produced prototype systems, but it has proven difficult to demonstrate that hidden switches and side channels do not exist. After almost thirty years of research and development, no viable and widely accepted system has emerged. We pursue a fundamentally different approach: Our prototype of an inspection system uses vintage hardware built around a 6502 processor. The processor uses 8-micron technology and has only about 4,200 transistors. Vintage electronics may have a number of important advantages for applications where two parties need to simultaneously establish trust in the hardware used. CPUs designed in the distant past, at a time when their use for sensitive measurements was never envisioned, drastically reduce concerns that the other party implemented backdoors or hidden switches on the hardware level. We demonstrate the performance of a prototype system using an Apple IIe and a custom-made open-source data-processing board connected to a standard sodium-iodide radiation detector for low-resolution gamma spectroscopy. Data processing and analysis is exclusively done on the Apple IIe hardware. We show that subtle differences in radiation signatures can be detected in 2-3 minutes based on the result of a simple chi-squared test. Vintage electronics may therefore offer a new path toward fieldable, trusted information barriers.

Arms-control agreements between the United States and Russia negotiated after the end of the Cold War have imposed limits on the number of deployed strategic nuclear weapons. Verification of these agreements has relied on onsite inspections, sometimes supported by radiation detection techniques to confirm the absence of a nuclear warhead when ambiguities arise. So far, these measurements have sought to detect neutron emissions associated with the presence of plutonium, but they would be inadequate for uranium devices. In an effort to offer instruments that could be used to confirm the absence of both plutonium and uranium weapons, here we propose an inspection system that uses only passive gamma radiation detection techniques. Such a system would be particularly valuable for next-generation arms-control agreements that limit total numbers of weapons and would involve containerized items in storage. We conducted extensive Monte Carlo simulations to support the development of a verification protocol and detection algorithm. We demonstrate the viability of the technique using standard laboratory check sources and MCNP simulations for simplified configurations of special nuclear material.