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This study examines associations between early childhood attachment security and adolescent personality functioning in a high-risk sample within a developmental psychopathology framework. Data from 2,268 children (1165 male; 1103 female) and caregivers participating in Future of Families and Child Well-Being Study (FFCWS) were used to examine (1) effects of genetic polymorphisms of the serotonin transporter (5-HTTLPR) and dopamine D4 receptor (DRD4) genes and adverse childhood experiences (ACEs) on attachment security and emotional and behavioral dysregulation in early childhood and (2) longitudinal associations and transactional relationships among attachment security, dysregulation, negative parenting attitudes and behaviors, social competence, and adolescent personality functioning. Results revealed that ACEs predicted attachment security over and above sex or the genetic risk, and gene × environment interactions did not increment prediction. Results of cascade models showed that greater early childhood attachment security predicted higher adolescent level of personality functioning via pathways through intermediary variables. Limitations and future research directions are discussed.
While the problem governing Stokes flow about a single particle that is subject to an external force is ill posed in two dimensions (the ‘Stokes paradox’), the related problem of two mutually repellent particles is well posed. Motivated by self-assembly phenomena in thin viscous membranes, we consider this problem in the limit of remote particles. Such limits are typically handled in the literature using reflection techniques, which provide successive approximations to the mutual hydrodynamic interactions. Since their starting point is a single particle in an unbounded fluid domain, these techniques are futile in the present two-dimensional problem. We show how this apparent contradiction is resolved via use of singular perturbations. We obtain a two-term approximation for the velocity acquired by circular disks, considering both rigid and free particle surfaces. We also illustrate our perturbation scheme for elliptic disks, deriving a renormalised single-particle velocity. The utility of our asymptotic scheme is illustrated in the general problem of hydrodynamic interaction between a cluster of remote disks.
The bubbly shock-driven partial cavitation in an axisymmetric venturi is studied with time-resolved two-dimensional X-ray densitometry. The bubbly shock waves are characterised using the vapour fraction and pressure changes across it, propagation velocity, and Mach number. The sharp changes in vapour fraction measured with X-ray densitometry, combined with high-frequency dynamic pressure measurements, reveal that the interaction of the pressure wave with the vapour cavity dictates the shedding dynamics. At the lowest cavitation number ($\sigma \sim 0.47$), the condensation shock front is the predominant shedding mechanism. However, as $\sigma$ increases ($\sigma \sim 0.78$), we observe an upstream travelling pressure discontinuity that changes into a condensation shock as it approaches the venturi throat. This coincides with the increasing strength of the bubbly shock wave as it propagates upstream, manifested by the increasing velocity of the shock front and the pressure rise across it. Consequently, the Mach number of the shock front increases and surpasses the critical value 1, favouring condensation shocks. Further, at higher $\sigma$ (${\sim }0.84\unicode{x2013}0.9$), both the re-entrant jet and pressure wave can cause cavity detachment. However, at such $\sigma$, the pressure wave likely remains subsonic. Hence cavity condensation is not favoured readily. This leads to the re-entrant jet causing the cavity detachment at higher $\sigma$. The shock front is accelerated as it propagates upstream through the variable cross-section of the venturi. This enhances its strength, favouring cavity condensation and eventual shedding. These observations explain the existence of shock fronts in an axisymmetric venturi for a large range of $\sigma$.
Minimally invasive compositional analyses of glass trade beads have revolutionised the study of these highly portable and socially significant items. Here, the authors interrogate new and legacy compositional data to investigate how Indigenous communities in eastern North America, particularly Wendat confederacy members, obtained beads from European traders and connected to broader interregional exchange systems c. AD 1600–1670. Diagnostic chemical elements in glass compositions reveal down-the-line exchange and population movement into the Western Great Lakes region prior to the arrival of European settlers, which highlights active Indigenous participation in transatlantic economic networks during a historical period of dynamic reorganisation and interaction.
This survey introduces the reader to the history of international zones. It argues that they offer striking insights into peacekeeping during the transition from a world of formal empires to one dominated by sovereign states. While the study of international zones is not new, there has been little examination of internationalization in practice. The survey suggests some of the benefits of adopting this approach and findings it might unearth.
The connection between ecological responsibility and differing conceptions of Christian eschatology is widely observed. It is often assumed that the necessary response to Christian environmental inaction is affirmation of a strongly this-worldly vision of new creation (so, influentially, N. T. Wright). However, recent systematic theology has seen retrieval of elements of eschatology that foreground discontinuity and transcendence (e.g. Hans Boersma). Moreover, there are exegetical challenges to continuationist claims (e.g. Markus Bockmuehl and Edward Adams) and doctrinal reactions to ‘eschatological naturalism’ (Katherine Sonderegger and Michael Allen). Where does this leave the connection between ecological witness and the content of Christian hope? Doubtless, continuationist accounts have some salutary emphases, but on exegetical, doctrinal and moral grounds I seek to disentangle the assumed compact of particular construals of this-worldly continuity and ethical commitment. Finally, drawing on James Cone's meditations upon black spiritual traditions, I explore how discontinuous interpretations of the life to come themselves need not undermine responsible action.
The COVID-19 has had major direct (e.g., deaths) and indirect (e.g., social inequities) effects in the United States. While the public health response to the epidemic featured some important successes (e.g., universal masking ,and rapid development and approval of vaccines and therapeutics), there were systemic failures (e.g., inadequate public health infrastructure) that overshadowed these successes. Key deficiency in the U.S. response were shortages of personal protective equipment (PPE) and supply chain deficiencies. Recommendations are provided for mitigating supply shortages and supply chain failures in healthcare settings in future pandemics. Some key recommendations for preventing shortages of essential components of infection control and prevention include increasing the stockpile of PPE in the U.S. National Strategic Stockpile, increased transparency of the Stockpile, invoking the Defense Production Act at an early stage, and rapid review and authorization by FDA/EPA/OSHA of non-U.S. approved products. Recommendations are also provided for mitigating shortages of diagnostic testing, medications and medical equipment.
Throughout the COVID-19 pandemic, many areas in the United States experienced healthcare personnel (HCP) shortages tied to a variety of factors. Infection prevention programs, in particular, faced increasing workload demands with little opportunity to delegate tasks to others without specific infectious diseases or infection control expertise. Shortages of clinicians providing inpatient care to critically ill patients during the early phase of the pandemic were multifactorial, largely attributed to increasing demands on hospitals to provide care to patients hospitalized with COVID-19 and furloughs.1 HCP shortages and challenges during later surges, including the Omicron variant-associated surges, were largely attributed to HCP infections and associated work restrictions during isolation periods and the need to care for family members, particularly children, with COVID-19. Additionally, the detrimental physical and mental health impact of COVID-19 on HCP has led to attrition, which further exacerbates shortages.2 Demands increased in post-acute and long-term care (PALTC) settings, which already faced critical staffing challenges difficulty with recruitment, and high rates of turnover. Although individual healthcare organizations and state and federal governments have taken actions to mitigate recurring shortages, additional work and innovation are needed to develop longer-term solutions to improve healthcare workforce resiliency. The critical role of those with specialized training in infection prevention, including healthcare epidemiologists, was well-demonstrated in pandemic preparedness and response. The COVID-19 pandemic underscored the need to support growth in these fields.3 This commentary outlines the need to develop the US healthcare workforce in preparation for future pandemics.
This exploratory text proposes a US imperial ‘research perspective’ on post-war post-colonial cities – cities that the United States did not colonially occupy, i.e. not cities like Manila, 1898–1946. US imperial actors and interests helped shape such cities, and in turn were shaped by their people and structures. Importantly, the US case seems to strengthen the general recent view, also regarding formal empires, that it makes little sense to posit the existence of an imperial city type, and more sense to use ‘the imperial urban’ as a research perspective.
A negative pressure wall-climbing robot is a special robot for climbing vertical walls, which is widely used in construction, petrochemicals, nuclear energy, shipbuilding, and other industries. The mobility and adhesion of the wheel-track wall-climbing robot with steering-straight mode are significantly decreased on the cylindrical wall, especially during steering. The reason is that the suction chamber may separate from the wall and the required driving force for movement increases, during steering. In this paper, a negative pressure wall-climbing robot with omnidirectional movement mode is developed. By introducing a compliant adjusting suction mechanism and omni-belt wheels, an omnidirectional movement mode is formed instead of the steering-straight mode, and the performances of adhesion and mobility are improved. We establish the safety adhesion model for the robot on a cylindrical wall and obtain the safety adhesion forces. We designed and manufactured an experimental prototype based on the analysis. Experiments showed that the robot has the ability of full maneuverability in cylindrical walls.
Throughout history, pandemics and their aftereffects have spurred society to make substantial improvements in healthcare. After the Black Death in 14th century Europe, changes were made to elevate standards of care and nutrition that resulted in improved life expectancy.1 The 1918 influenza pandemic spurred a movement that emphasized public health surveillance and detection of future outbreaks and eventually led to the creation of the World Health Organization Global Influenza Surveillance Network.2 In the present, the COVID-19 pandemic exposed many of the pre-existing problems within the US healthcare system, which included (1) a lack of capacity to manage a large influx of contagious patients while simultaneously maintaining routine and emergency care to non-COVID patients; (2) a “just in time” supply network that led to shortages and competition among hospitals, nursing homes, and other care sites for essential supplies; and (3) longstanding inequities in the distribution of healthcare and the healthcare workforce. The decades-long shift from domestic manufacturing to a reliance on global supply chains has compounded ongoing gaps in preparedness for supplies such as personal protective equipment and ventilators. Inequities in racial and socioeconomic outcomes highlighted during the pandemic have accelerated the call to focus on diversity, equity, and inclusion (DEI) within our communities. The pandemic accelerated cooperation between government entities and the healthcare system, resulting in swift implementation of mitigation measures, new therapies and vaccinations at unprecedented speeds, despite our fragmented healthcare delivery system and political divisions. Still, widespread misinformation or disinformation and political divisions contributed to eroded trust in the public health system and prevented an even uptake of mitigation measures, vaccines and therapeutics, impeding our ability to contain the spread of the virus in this country.3 Ultimately, the lessons of COVID-19 illustrate the need to better prepare for the next pandemic. Rising microbial resistance, emerging and re-emerging pathogens, increased globalization, an aging population, and climate change are all factors that increase the likelihood of another pandemic.4
The city of Sapporo, founded in 1869 by the Japanese government as a colonial headquarters in Hokkaido, developed as part of a global wave of settler-colonial urbanism. Like counterparts in North America and Australia, Sapporo facilitated economic, environmental and political transformations across Hokkaido that led to the displacement of Indigenous Ainu society by a soon overwhelming number of ethnically Japanese settlers. However, several historical factors distinguish Sapporo’s settler-colonial urbanism from its peers, including the long history of relations between the Ainu and Japanese; the heavy role of the Japanese state in Sapporo; and the lack of mass relocations of the Ainu to reservations far from their traditional homes.
Organic acids are commonly found in soils and sediments, playing an important role in the alteration and weathering of minerals and influencing a series of geochemical processes such as soil fertility, metal cycling and pollutant migration. In order to better comprehend the reaction mechanisms of different layered silicate minerals with organic acids, three minerals with various structure types, namely montmorillonite, kaolinite and muscovite, were investigated in this work. In particular, the effects of interfacial reactions with oxalic acid on the crystal structure, chemical composition, morphology and specific surface area of minerals were compared. The composition and structure of montmorillonite, kaolinite and muscovite during the interfacial reaction with oxalic acid were characterised using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) methods. It was shown that Si4+ and Al3+ were dissolved gradually during the interfacial reactions and that the changes in the properties of minerals depended on structural characteristics. After 300 days of the interfacial reactions with oxalic acid, the dissolution percentages of Si4+ and Al3+ in montmorillonite, kaolinite and muscovite were 12.7%, 8.4%, 3.8% and 62.1%, 30.7%, 6.1%, respectively. Moreover, the lamellar morphology of montmorillonite was destroyed upon the interfacial reaction with oxalic acid, and irregular particles with sizes of ~100–500 nm were formed on the surface. The diameter of kaolinite flake particles decreased from 400–1500 nm to 50–400 nm, and the surface of rod-shaped particles was ruptured. The small particles disappeared from the muscovite surface, and the initially sharp edges became blunted. The specific surface area and the total pore volume of montmorillonite and kaolinite increased after the interfacial reaction with oxalic acid, whereas the opposite results were obtained for muscovite. The differential dissolution of the minerals during their interfacial reaction with oxalic acid was mainly related to the differences between cation occupancies, structural types, chemical bond strengths and specific surface areas.
Let K denote prefix-free Kolmogorov complexity, and let $K^A$ denote it relative to an oracle A. We show that for any n, $K^{\emptyset ^{(n)}}$ is definable purely in terms of the unrelativized notion K. It was already known that 2-randomness is definable in terms of K (and plain complexity C) as those reals which infinitely often have maximal complexity. We can use our characterization to show that n-randomness is definable purely in terms of K. To do this we extend a certain “limsup” formula from the literature, and apply Symmetry of Information. This extension entails a novel use of semilow sets, and a more precise analysis of the complexity of $\Delta _2^0$ sets of minimal descriptions.
The Society for Healthcare Epidemiology in America (SHEA) strongly supports modernization of data collection processes and the creation of publicly available data repositories that include a wide variety of data elements and mechanisms for securely storing both cleaned and uncleaned data sets that can be curated as clinical and research needs arise. These elements can be used for clinical research and quality monitoring and to evaluate the impacts of different policies on different outcomes. Achieving these goals will require dedicated, sustained and long-term funding to support data science teams and the creation of central data repositories that include data sets that can be “linked” via a variety of different mechanisms and also data sets that include institutional and state and local policies and procedures. A team-based approach to data science is strongly encouraged and supported to achieve the goal of a sustainable, adaptable national shared data resource.