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The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists' Nuclear Information Project: director Hans M. Kristensen, senior research associate Matt Korda, and research associate Eliana Johns. The Nuclear Notebook column has been published in the Bulletin of the Atomic Scientists since 1987. This issue's column reviews the status of France's nuclear arsenal and finds that the stockpile of approximately 290 warheads has remained stable in recent years, but that significant modernizations are underway regarding ballistic missiles, cruise missiles, submarines, aircraft, and the nuclear industrial complex. To see all previous Nuclear Notebook columns, go to . [ABSTRACT FROM AUTHOR]

[Display omitted] The scientific paper presents studies of the radiation-protective features of a polymer composite material for protection against space radiation based on poly-tetra-fluoro-ethylene, Bi 2 O 3 bismuth oxide, WC tungsten carbide, B 4 C boron carbide, TiH 1.7 titanium hydride shot. The composite provides for a high degree of protection against ionizing radiation, including protection against exposure to secondary neutrons: macroscopic fast neutrons removal cross-section (E > 2 MeV) 0.1331–0.1414 cm−1, thermal-velocity neutrons removal cross-section (E < 0.4 eV), cm−1 0.1183–0.1257 cm−1. A shield made of the tailored composition of the proposed 6 cm thick polymer composite attenuates the intensity of neutron radiation by more than 50 % at energies from 0.1 to 5 MeV, in particular, the greatest attenuation of the neutron radiation intensity occurs at an energy of 0.1 MeV with a sharp increase in attenuation when passing through a 2 cm thick shield and complete absorption occurs passing through a 6 cm thick shield. This material can be used to protect astronauts and radio-electronic equipment from the effects of adverse or harmful space factors, including exposure to secondary neutrons, and this material can also be used to protect crews of ships with mobile nuclear reactors such as atomic submarines and nuclear-powered icebreakers. [ABSTRACT FROM AUTHOR]

Introduction Since the start of the Global War on Terrorism, exponential demands have been put on military personnel, their families, and the military health care system. In response to a Department of Defense Task Force on Mental Health, the U.S. military began developing and fielding programs to promote the psychological health of its personnel. As part of these initiatives, the Navy and Marine Corps developed the Stress Continuum model. The Stress Continuum is a stress classification system ("ready," "reacting," "injured," and "ill") that provides a common language for identifying, engaging, and intervening when stress reactions or stress injuries are present in military personnel. It is the foundation for resilience and prevention efforts across the Navy and Marine Corps. Although the Stress Continuum has strong face validity, is consistent with current theory, and has been agreed up by expert consensus, it has yet to be empirically validated. The goal of the current article is to begin to empirically validate the Stress Continuum using validated measures of psychological stress. Materials and Methods We conducted a retrospective analysis of Stress Continuum data (n  = 2,049) collected as part of a program evaluation of two Navy operational stress control programs. Receiver operating characteristic (ROC) curves and analyses were conducted to determine the classification quality of the Stress Continuum using a validated measure of stress (a brief version of the Perceived Stress Scale [PSS-4]). Results For the first ROC curve, we used the "ill" category (vs. the other three categories) to identify the cut point on the PSS-4. PSS-4 cut point values of 9 and 10, respectively, maximized sensitivity and 1-specificity values. Using the chi-square test, we further found that a more accurate prediction for those in the "ill" category was using the cut point of 9 (79%) relative to 10 (71.8%). For the second and the third ROC curves, we used the "ill" and "injured" categories (vs. the other two categories) and "ill," "injured," and "reacting" categories (vs. the "ready" category), respectively. No optimal cut points on the PSS-4 were identified for these models, indicating that the PSS-4 could not reliably differentiate true-positive and false-positive rates. Conclusions We found that the "ill" category of the Stress Continuum was predictive of higher levels of stress on the validated measure of perceived stress. Thus, our findings strongly suggest that the individuals in the "ill" zone likely warrant some type of intervention by a trained professional. Future Research The Navy has recently leveraged the Stress Continuum to create the Stress-o-Meter to support the fundamental principles of early recognition, peer intervention, and connection to services at the unit level. The Stress-o-Meter serves as a prevention tool that has the capability to collect information about stress levels throughout the entire unit at any time. Continued work on validating the Stress Continuum model and making it easily accessible to military units will ensure service members get the support they need and leaders are able to address the psychological health of their units. [ABSTRACT FROM AUTHOR]

This article discusses the life and contributions of Earl "Pete" Hancock Ellis, a Marine Corps officer who played a significant role in shaping the Marine Corps' mission and doctrine in the early 20th century. Ellis advocated for advanced base operations and amphibious assault missions, which were eventually embraced by the Navy and Marine Corps. His ideas were outlined in a document called "Advanced Base Operations in Micronesia," and he emphasized the need for specialized training in water and jungle warfare. While Ellis's contributions are acknowledged, the article emphasizes the collective effort and the role of other influential figures in shaping the Marine Corps' mission. [Extracted from the article]

For species of conservation concern, long‐term monitoring is vital to properly characterize changes in population distribution and abundance over time. In addition, long‐term monitoring guides management decisions by informing and evaluating the efficacy of management actions. A long‐term monitoring initiative for the federally threatened Stephens' Kangaroo rat (Dipodomys stephensi, SKR) was established in 2005, across 628 hectares within Marine Corps Base Camp Pendleton (MCBCP), San Diego, California, USA. From 2005 to 2018, we tracked trends in area occupied by SKR, trends in relative SKR densities within occupied habitat, and modeled probabilities of SKR occupancy, colonization, extinction, with habitat, climate, and disturbance covariates. Area occupied by SKR increased almost 2‐fold from 2005 to 2018 on MCBCP, while density in occupied habitat increased almost 3‐fold. Increased area occupied was correlated with increases in estimated density among years, indicating SKR population growth occurs by expansion into suitable habitat patches, as well as increases in numbers within occupied habitat. SKR occupancy was positively associated with gentle slopes (<10%) and moderate open ground (40–80%) and forb cover (>40%). They were more likely to colonize previously unoccupied habitat when there were moderate levels of open ground (40–80%) and low shrub cover (<20%), while more likely to go locally extinct in areas with high slopes (>10%), less open ground (<20%), and increased non‐native grass cover (>40%). Additionally, probabilities of SKR occupancy and colonization were higher in areas with moderate levels of disturbance, which was positively associated with open ground and forb cover. We conclude that long‐term occupancy and density monitoring is effective in informing status and trends of spatially dynamic species and that moderate habitat‐based disturbance is compatible with the management of SKR. [ABSTRACT FROM AUTHOR]

Isoxeniolid A ist ein hochgespanntes marines Diterpenoid aus der Familie der Xenicane. Es steht repräsentativ für eine Unterfamilie von Xenicanen, deren 9‐gliedriger Ring eine allylische Hydroxygruppe aufweist; derartige Xenicane wurden bisher nicht als Zielmoleküle von Totalsynthesen verfolgt. Wir beschreiben hier die erste asymmetrische Totalsynthese eines derartigen Xenicans, nämlich des Isoxeniolid A. Dabei lag der Schlüssel zum Aufbau des besonders herausfordernden E‐konfigurierten Cyclononenrings in einer diastereoselektiven intramolekularen Nozaki–Hiyama—Kishi‐Reaktion. Andere wichtige Transformationen waren eine enzymatische Desymmetrisierung zur Kontrolle der absoluten Stereochemie, eine diastereoselektive Cuprat‐Addition und die Verwendung eines bifunktionalen Vinylsilan‐Bausteins. Unsere Synthesestrategie ermöglicht auch den Zugang zur enantiomeren Form des Naturstoffs sowie prinzipiell zu einer Vielzahl anderer natürlicher Xenicane und synthetischer Analoga für Struktur‐Aktivitäts‐Untersuchungen. [ABSTRACT FROM AUTHOR]

The article discusses the Glomar Explorer, a vessel built by the CIA in 1974 to retrieve a sunken Soviet nuclear submarine. The author, M. Todd Bennett, provides a comprehensive account of the mission and its implications for intelligence, transparency, and diplomacy. Bennett argues that the Glomar mission was a response to congressional investigations and a way for the CIA to push back against scrutiny. The article also highlights the role of the media in reporting on national security issues and the diplomatic implications of the operation. Despite differing opinions on the success of the mission, Bennett's work is seen as a valuable contribution to the literature on intelligence and diplomatic history. [Extracted from the article]

The Nuclear Notebook is researched and written by Hans M. Kristensen, director of the Nuclear Information Project with the Federation of American Scientists, and Matt Korda, a senior research associate with the project. The Nuclear Notebook column has been published in the Bulletin of the Atomic Scientists since 1987. This issue examines North Korea's nuclear arsenal. The authors cautiously estimate that North Korea may have produced enough fissile material to build between 45 and 55 nuclear weapons; however, it may have only assembled 20 to 30. [ABSTRACT FROM AUTHOR]

The Nuclear Notebook is researched and written by Hans M. Kristensen, director of the Nuclear Information Project with the Federation of American Scientists, and Matt Korda, a senior research associate with the project. The Nuclear Notebook column has been published in the Bulletin of the Atomic Scientists since 1987. This issue examines the status of India's nuclear arsenal, which includes a stockpile of approximately 160 warheads. India continues to modernize its nuclear arsenal, with at least four new weapon systems now under development to complement or replace existing nuclear-capable aircraft, land-based delivery systems, and sea-based systems. Several of these systems are nearing completion and will soon be combat-ready. India is estimated to have produced enough military plutonium for 140 to 210 nuclear warheads but has likely produced only 160. Nonetheless, additional plutonium will be required to produce warheads for missiles now under development, and India is reportedly building several new plutonium production facilities. India's nuclear strategy, which has traditionally focused on Pakistan, now appears to place increased emphasis on China, and Beijing is now in range of Indian missiles. [ABSTRACT FROM AUTHOR]

This article considers logistics and supply in the China Relief Expedition. In the China campaign, as in all armed conflicts, the availability of matériel and subsistence determined what military options were available to commanders. In 1900, because of a strong industrial base and a burgeoning logistical network, the US Army, Marine Corps, and Navy demonstrated an increased capacity and capability to project power on hemispheric scales. Throughout the entirety of their intervention in China, Americans moved animals, artillery, medical supplies, men, ordnance, and subsistence across great distances – over sea and land, to and within the theatre of operations – with remarkable efficiency under difficult conditions. Thus, the China Relief Expedition was instructive for the US profession of arms, and pointed to a future in which large-scale combat operations on land and at sea would require careful integration and more extensive logistical support than military operations of nineteenth-century conflicts. [ABSTRACT FROM AUTHOR]

Military service members (SMs) demonstrate high rates of patellofemoral chondral defects (PFCDs) that are difficult to diagnosis and, if untreated, result in a cascade of events eventually leading to osteoarthritis. Running is an essential occupational task for SMs; however, there is little evidence regarding techniques to maintain running ability in individuals with cartilage defects. The purpose of this case series was to assess the clinical application of foot strike run retraining in patients with PFCDs. This case series included two active duty U.S. Marine Corps SMs who presented to outpatient physical therapy with PFCD, diagnosed via MRI. Both patients attended eight foot strike run retraining sessions. Running mechanics and patient-reported outcomes were recorded pre-training, post-training, and at a 1-month follow-up visit. Both patients successfully converted their strike pattern from a rearfoot to a non-rearfoot strike pattern with training and retained this strategy at 1-month follow-up. Post-intervention, both patients demonstrated increased running tolerance, and improvements in Numeric Pain Rating Scale and Lower Extremity Functional Scale scores. Biomechanical analysis showed that both patients demonstrated a 63% to 70% reduction in average and peak vertical ground reaction force loading rates post-treatment. Modification of foot strike pattern from rear to non-rearfoot strike during running for individuals with PFCD can reduce the magnitude of impact loading, which potentially limits disease progression. These findings suggest that foot strike run retraining may be a feasible strategy to reduce pain and improve function in SMs with PFCD who are required to run for occupational responsibilities. [ABSTRACT FROM AUTHOR]

3d Reconnaissance Battalion, a forward-deployed Marine Corps unit in Okinawa, Japan, frequently performs diving operations. Often throughout the year, several reconnaissance teams are diving simultaneously in different locations for training. We present a case of an otherwise healthy 30-year-old-male Reconnaissance Marine who surfaced from a dive with abnormal symptoms and received prompt care from exercise participants who were nonmedical personnel. Studies have demonstrated improved morbidity outcomes in decompression illness patients with shorter times to hyperbaric treatment following the onset of symptoms. High-risk military exercises with diving components have a mandatory safety structure that includes recompression chamber support. All United States Marine Corps Reconnaissance, Marine Corps Special Operations Command, and U.S. Navy dive operations are required to have at least one diving supervisor. To expand the diving capabilities of the unit, Marines are encouraged to attend training and qualify as diving supervisors. This case study demonstrates the efficacy and importance of training Recon Marines to recognize decompression illness as diving supervisors. [ABSTRACT FROM AUTHOR]

AUKUS is an agreement among Australia, Britain and the United States to enable Australia to acquire nuclear-powered submarines (Pillar 1) and to undertake research and development of novel defence technologies (Pillar 2). This paper describes the AUKUS tripartite relationship; outlines the eight AUKUS Pillar 2 technology and col laboration initiatives; and looks in detail at the planning for Australia's acquisition of nuclear-powered attack submarines under AUKUS Pillar 1. Strategic implications for Australia and the Indo-Pacific region are noted and the author concludes that AUKUS will provide a foundation for enhanced national and regional security. [ABSTRACT FROM AUTHOR]

The article provides an overview of political developments in Australia from January to June 2023. It discusses the Labor government's focus on trade union concerns and its pursuit of specific ideological agendas, such as increasing wages and job creation. The government faced challenges related to inflation and tighter monetary policy. Notable events mentioned include the establishment of the National Anti-Corruption Commission and the Indigenous Voice referendum. The article also highlights troubles and scandals, including a poorly conceived discussion paper on superannuation, a scandal involving a former senator, and a consultancy firm leaking confidential information. Additionally, it provides updates on various political figures and mentions the announcement of the purchase of nuclear-powered submarines and the release of the budget for 2023-24. [Extracted from the article]

In 2003, Iraq was invaded, ostensibly to remove a nuclear threat, by a coalition led by George W. Bush. At the same time select allies were invitited to participate in Bush's Global Nuclear Energy Partnership which aimed to limit the spread of nuclear enrichment and reprocessing. This came as climate change gave emphasis to the development of nuclear energy, especially in Asia. With an abundant supply of uranium and strict nuclear safeguards, Australia was well placed to provide a site for the full suite of nuclear services. The recent AUKUS nuclear submarine agreement has underscored its failure to do so. This article makes the case for the adoption of nuclear power as a necessary step in the development of advanced manufacturing; the provision of a domestic capability to fuel nuclear attack submarines and other naval craft; and as a contribution to global nuclear non‐proliferation. [ABSTRACT FROM AUTHOR]

Forging Wargamers: A Framework for Professional Military Education is a collection of essays edited by Sebastian J. Bae that aims to provide tools and skills for the advancement of wargaming education. The book includes contributions from practitioners and scholars in the field of wargaming, covering topics such as the perception of wargaming as a profession, integrating wargaming into military training, and the inclusion of social science principles in analytic wargames. While the book offers diverse perspectives and valuable insights, it could benefit from additional interdisciplinary perspectives and direct testimonials. Overall, it serves as a useful resource for individuals interested in wargaming. [Extracted from the article]

The West India Regiments, men of African descent embodied into regular regiments of the British Army, played a hitherto unheralded role in the War of 1812. Knowledge of the military prowess of these regiments was widespread in the US in the early nineteenth century, and the British exploited this, mixed with a large amount of rumour and speculation as a terror tactic during the war. The West India Regiments were used as recruiters in the Chesapeake in 1814, and on active campaigns against New Orleans and Georgia in 1815. They were directly and indirectly responsible for the escape of thousands of enslaved people from slave states to British forces and even forced some US commentators to contemplate the recruitment of their own enslaved soldiers as a counterweight. While their military contribution to the war ended up being small, the psychological importance of regiments of black men within easy reach of the southern states lingered long after peace had been agreed. [ABSTRACT FROM AUTHOR]

The Australia-United Kingdom-United States (AUKUS) partnership arose because of Australia's need to replace its ageing submarine fleet, opting for nuclear-powered submarines to be built with American and British assistance. Perceptions of a deteriorating strategic situation vis-à-vis China were a major factor in this decision. Through AUKUS, the United Kingdom will also acquire additional submarines and expand its strategic role in the Indo/Asia-Pacific region. In addition to the submarine plan, AUKUS has a focus on the development of advanced defence technology. AUKUS has significant implications for Asian and Pacific Commonwealth countries, with their responses reflecting their strategic outlooks and perceived defence needs, [ABSTRACT FROM AUTHOR]

A conflict between Taiwan and China might involve a full-scale invasion, or a more limited coercion campaign in which China seeks to cause Taiwan enough pain to cause it to change its behavior. If the United States chooses to intervene in such a conflict on Taiwan's behalf, it can likely prevent China from invading Taiwan but might not be able to prevent Taiwan from being coerced. For this reason, the United States would be mistaken if it completely abandoned its policy of ambiguity about defending Taiwan. If the United States were to change its policy of ambiguity, it should do so only in the case of an invasion and remain ambiguous as to whether and how it would respond to a Chinese coercion campaign. [ABSTRACT FROM AUTHOR]

The US network of military alliances and security partnerships in the region has allowed it to influence Indo-Pacific affairs. But, a rapid shift in the balance of power in favour of China has threatened the US interests and security commitments with its regional allies. Hence, the AUKUS is a continuance of the US strategy of pivoting to Asia conceived by the Obama administration and a part of broader US efforts to balance revisionist China in the Indo-Pacific. Through AUKUS, the US has an opportunity to enhance the capabilities of its ally, Australia, to balance aggressive China. Convergence of security and foreign policy objectives with the US has encouraged Britain and Australia to be the parties of AUKUS. AUKUS would boost Australia's capabilities for shaping its regional strategic and security environment and develop a durable strategic power balance in the region. As a natural ally of the US and Australia, Britain also opposes China's illegal territorial claims and activities in the South and East China Seas and has developed a policy of integrated and collective actions with allies to protect the common interests through the AUKUS partnership. [ABSTRACT FROM AUTHOR]

At the early design stage of a submarine, it is necessary to have a good estimate of the linear manoeuvring coefficients, or derivatives. These are necessary to determine the required size of any appendages to achieve the desired level of motion stability and controllability. Various empirical methods exist to make such estimates, including the influence of appendages. However, methods do not exist to predict the linear rotary coefficients (i.e. Y r ′ and N r ′ ) for a bare hull. Thus, the aim of this work was to determine the values of the linear rotary coefficients for an axisymmetric underwater body as functions of Length to Diameter (L/D) ratio to improve the empirical estimate of these values for a fully appended submarine. The work was performed using validated Reynolds Averaged Navier Stokes (RANS) based simulations to obtain forces and moments on the body. It is considered that the developed expressions for the linear rotary coefficients are adequate for an unappended axisymmetric underwater body at the design stage over the range: 6 ≤ L/D ≤ 14, which can then be used to size and locate the appendages. [ABSTRACT FROM AUTHOR]

The Nuclear Notebook is researched and written by Hans M. Kristensen, director of the Nuclear Information Project with the Federation of American Scientists, and Matt Korda, a research associate with the project. The Nuclear Notebook column has been published in the Bulletin of the Atomic Scientists since 1987. This issue's column examines North Korea's nuclear arsenal. The authors cautiously estimate that North Korea may have produced enough fissile material to build between 40 and 50 nuclear weapons; however, it may not have actually assembled that many. To see all previous Nuclear Notebook columns, visit . [ABSTRACT FROM AUTHOR]

The Nuclear Notebook is researched and written by Hans M. Kristensen, director of the Nuclear Information Project with the Federation of American Scientists, and Matt Korda, a research associate with the project. The Nuclear Notebook column has been published in the Bulletin of the Atomic Scientists since 1987. This issue's column examines the United Kingdom's nuclear arsenal, which includes a stockpile of approximately 225 warheads. Of these, up to 120 are operationally available for deployment on four ballistic missile submarines. In 2021, however, the government announced the UK would increase its stockpile ceiling to up to 260 warheads. To see all previous Nuclear Notebook columns, go to . [ABSTRACT FROM AUTHOR]

"The Atomic Archipelago: US Nuclear Submarines and Technopolitics of Risk in Cold War Italy" by Davide Orsini explores the history of the U.S. Navy's military base in La Maddalena, Italy, between 1972 and 2008. The base was strategically located to monitor Soviet underwater activities in the Mediterranean. Orsini examines the debates and conflicts surrounding radiological risk in and around the base, shedding light on the history of science and technology during the Cold War. The book also discusses the complex Italian legislation concerning radio-ecological surveys and the challenges faced by scientists and public agencies in establishing an efficient monitoring system. Additionally, it explores the experiences and reactions of the local population to the U.S. military presence and highlights the interaction between expert understandings of radiological risk and perceptions of risk by the community. Overall, "The Atomic Archipelago" offers a unique perspective on knowledge production in the field of radiological risk during the Cold War. [Extracted from the article]

The experience of Marine battalions rotated through the Mediterranean in the early Cold War illustrates the challenges of forward deployment, which became an increasingly common experience for the American military due to the militarization of containment. Examining the first ten years of these deployments shows how the Marine Corps worked to overcome some of these challenges while others remained intractable. The deployments reflected the broader contours of American defense policy: growing forward deployments as Truman’s containment of the Soviet Union came to rely more on military power, the novel operational demands of regularly training with allies, the subordination of secondary activities to support operations in Korea, and the economizing effects of the New Look. [ABSTRACT FROM AUTHOR]

Until the United States entered World War II, Britain’s isolation left it vulnerable to U-boats. Yet even when the campaign appeared to be going well, the German Naval War Staff worried that it was likely to be unsuccessful. The staff’s pessimism has been largely absent from the Anglophone historiography. The fundamental problem was that the Germans needed to secure a decisive result quickly, before the full weight of U.S. industrial might could be felt, but they were deploying a weapon designed for a long war. This article calls attention not only to this dilemma, but to the German awareness of it. [ABSTRACT FROM AUTHOR]

The Nuclear Notebook is researched and written by Hans M. Kristensen, director of the Nuclear Information Project with the Federation of American Scientists, and Matt Korda, a research associate with the project. The Nuclear Notebook column has been published in the Bulletin of the Atomic Scientists since 1987. This issue's column examines Russia's nuclear arsenal, which includes a stockpile of nerarly 4,500 warheads. Of these, some 1,600 strategic warheads are deployed on ballistic missiles and at heavy bomber bases, while an additional 985 strategic warheads, along with 1,912 nonstrategic warheads, are held in reserve. The Russian arsenal is continuing broad modernization intended to replace most Soviet-era weapons by the mid- to late 2020s. To see all previous Nuclear Notebook columns, go to . [ABSTRACT FROM AUTHOR]

The following article considers the implications of the AUKUS security pact for Australia, noting obstacles to implementing the tripartite security alliance involving the deployment of nuclear technology and the expansion of the current US military presence in Australia. The paper argues that the efforts to implement AUKUS in various ways face three fundamental obstacles, thereby challenging Australia’s militarisation. The first involves challenges in acquiring a nuclear-propulsion submarine fleet both in terms of constructing a new design and purchasing existing models from the US. The second considers the growing unpopularity of AUKUS and efforts to militarise and garrison Australia as a US satellite. The third considers the complexities and challenges of storing nuclear waste arising from the vessels. To that end, the paper concludes that the objectives of the alliance may prove unworkable on several levels. [ABSTRACT FROM AUTHOR]

Introduction: Neuromusculoskeletal injuries (NMSKI) are very common in the military, which contribute to short- and long-term disability. Materials and Methods: Population-level NMSKI, limited duty (LIMDU), and long-term disability episode counts in the U.S. Navy (USN) and U.S. Marine Corps (USMC) from December 2016 to August 2021 were extracted from the Musculoskeletal Naval Epidemiological Surveillance Tool. The incidence of NMSKI, LIMDU, and long-term disability was calculated. A hurdle negative binomial regression evaluated the association of body region, sex, age, rank, age by rank, and service branch on NMSKI, LIMDU, and long-term disability incidence. Results: From December 2016 to August 2021, there were 2,004,196 NMSKI episodes (USN: 3,285/1,000 Sailors; USMC: 4,418/1,000 Marines), 16,791 LIMDU episodes (USN: 32/1,000 Sailors; USMC: 29/1,000 Marines), and 2,783 long-term disability episodes (USN: 5/1,000 Sailors; USMC: 5/1,000 Marines). There was a large-magnitude protective effect on NMSKI during the pandemic (relative risk, USN: 0.70; USMC: 0.75). Low back and ankle-foot were the most common, primarily affecting female personnel, aged 25-44 years, senior enlisted, in the USMC. Shoulder, arm, pelvis-hip, and knee conditions had the greatest rates of disability, with female sex, enlisted ranks, aged 18-24 years, and service in the USMC having the most salient risk factors. Conclusion: Body region, sex, age, rank, and branch were the salient factors for NMSKI. The significant protective effect during the pandemic was likely a function of reduced physical exposure and limited access to nonurgent care. Geographically accessible specialized care, aligned with communities with the greatest risk, is needed for timely NMSKI prevention, assessment, and treatment. [ABSTRACT FROM AUTHOR]

The U.S. Navy and Newport News Shipbuilding have between them created an unusual – probably unique – monopoly-monopsony duet, in this case for construction and refueling of nuclear aircraft carriers. Monopoly-monopsony dynamics captured a modest amount of theoretical attention, beginning with Francis Y. Edgeworth in the late 19th century. These analyses generally agreed such markets required a kind of collaboration between buyer and seller unlike the usual dynamic of competitive or monopoly-multiple customer markets. This conclusion is tested and confirmed through a story of the history of the formation of the Navy-Newport News monopoly-monopsony duet. [ABSTRACT FROM AUTHOR]

The paper analyses accidents and emergencies that occurred at reactor plants having a lead-bismuth eutectic (LBE) located in nuclear submarines and prototype ground-based facilities. Accidents and emergencies are systematized according to the initiating events and causes, as well as their consequences, and the measures developed for their future prevention. In the course of mastering the reactor technology, important scientific and technical problems, including the LBE technology itself, the corrosion resistance of structural materials, radiation safety under Po-210 emissions, the reliability of steam generators and associated equipment under coolant freezing-melting conditions, are studied with a view to providing their solutions. [ABSTRACT FROM AUTHOR]

Introduction Medical readiness to deploy is an increasingly important issue within the military. Musculoskeletal back pain is one of the most common medical problems that affects service members. This study demonstrates the associations between risk factors and the prevalence of musculoskeletal back pain among active duty sailors and Marines within the Department of the Navy (DoN). Materials and Methods Utilizing the Military Health System Data Repository, we conducted a retrospective cross-sectional review of administrative healthcare claim data for all active duty DoN personnel with at least one medical encounter during fiscal years 2009-2015. For each fiscal year, we identified all claims with an ICD-9 code for back pain and calculated prevalence. We compared those with and without back pain across all variables (age, gender, rank, race, body mass index, tobacco use, occupation, and branch of service) using chi-square analysis. Unadjusted and adjusted log-binomial regressions were used to calculate prevalence ratios and examine associated risk factors for back pain. Results The number of active duty subjects per fiscal year ranged from 424,460 to 437,053. The prevalence of back pain showed an upward trend, ranging from 9.99% in 2009 to 12.09% in 2015. Personnel aged 35 years and older had the strongest adjusted prevalence ration (APR) for back pain (APR 2.59; 95% CI, 2.53-2.66). There were also strong associations with obese body mass index (APR 1.76; 95% CI, 1.66-1.86), overweight body mass index (APR 1.29; 95% CI, 1.27-1.32), and tobacco use (APR 1.39; 95% CI, 1.36-1.42). Females were more likely to have back pain than males (APR 1.43; 95% CI, 1.40-1.47) and Marines more likely than sailors (APR 1.39; 95% CI, 1.36-1.42). The occupation with the highest prevalence ratio was healthcare (APR 1.34; 95% CI, 1.29-1.40) when compared to the reference group of combat specialists. Conclusions There was an increasing prevalence of back pain across the DoN from 2009 to 2015. Different occupational categories demonstrate different prevalence of back pain. Surprisingly, combat occupations and aviators were among the groups with the lowest prevalence. Lifestyle factors such as excess body weight and use of tobacco products are clearly associated with increased prevalence. These results could inform military leaders with regard to setting policies that could increase medical readiness. [ABSTRACT FROM AUTHOR]