To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Modern anaesthesia and sedation consists of giving combinations of hypnotic and analgesic drugs to obtain the desired anaesthetic effect. Understanding how these drugs interact to create the anaesthetic state improves the precision of anaesthetic drug dosing and physiological stability of the patient.
Residential burglary is a social problem in every major urban area. As such, progress has been to develop quantitative, informative and applicable models for this type of crime: (1) the Deterministic-time-step (DTS) model [Short, D’Orsogna, Pasour, Tita, Brantingham, Bertozzi & Chayes (2008) Math. Models Methods Appl. Sci.18, 1249–1267], a pioneering agent-based statistical model of residential burglary criminal behaviour, with deterministic time steps assumed for arrivals of events in which the residential burglary aggregate pattern formation is quantitatively studied for the first time; (2) the SSRB model (agent-based stochastic-statistical model of residential burglary crime) [Wang, Zhang, Bertozzi & Short (2019) Active Particles, Vol. 2, Springer Nature Switzerland AG, in press], in which the stochastic component of the model is theoretically analysed by introduction of a Poisson clock with time steps turned into exponentially distributed random variables. To incorporate independence of agents, in this work, five types of Poisson clocks are taken into consideration. Poisson clocks (I), (II) and (III) govern independent agent actions of burglary behaviour, and Poisson clocks (IV) and (V) govern interactions of agents with the environment. All the Poisson clocks are independent. The time increments are independently exponentially distributed, which are more suitable to model individual actions of agents. Applying the method of merging and splitting of Poisson processes, the independent Poisson clocks can be treated as one, making the analysis and simulation similar to the SSRB model. A Martingale formula is derived, which consists of a deterministic and a stochastic component. A scaling property of the Martingale formulation with varying burglar population is found, which provides a theory to the finite size effects. The theory is supported by quantitative numerical simulations using the pattern-formation quantifying statistics. Results presented here will be transformative for both elements of application and analysis of agent-based models for residential burglary or in other domains.
The response of glaciers to climate change has major implications for sea-level change and water resources around the globe. Large-scale glacier evolution models are used to project glacier runoff and mass loss, but are constrained by limited observations, which result in models being over-parameterized. Recent systematic geodetic mass-balance observations provide an opportunity to improve the calibration of glacier evolution models. In this study, we develop a calibration scheme for a glacier evolution model using a Bayesian inverse model and geodetic mass-balance observations, which enable us to quantify model parameter uncertainty. The Bayesian model is applied to each glacier in High Mountain Asia using Markov chain Monte Carlo methods. After 10,000 steps, the chains generate a sufficient number of independent samples to estimate the properties of the model parameters from the joint posterior distribution. Their spatial distribution shows a clear orographic effect indicating the resolution of climate data is too coarse to resolve temperature and precipitation at high altitudes. Given the glacier evolution model is over-parameterized, particular attention is given to identifiability and the need for future work to integrate additional observations in order to better constrain the plausible sets of model parameters.
We present a theory for the evolution of a one-dimensional, steady-state detonation reaction zone to a two-dimensional reaction zone, when the explosive experiences a sudden loss of side-on confinement as a boundary of the explosive is impulsively withdrawn. Our focus is on condensed-phase explosives, which we describe as having a constant adiabatic gamma equation of state and an irreversible, state-independent reaction rate. We consider two detonation models: (i) the instantaneous reaction heat release Chapman–Jouguet (CJ)-limit and (ii) the spatially resolved reaction heat-release Zel’dovich–von Neumann–Döring (ZND) model, in the limit where only a small fraction of the energy release is resolved (the SRHR-limit). Two competing rarefaction waves are generated by this loss of confinement: (i) a smooth wave coming off the full length of the withdrawn boundary and (ii) a singular fan spreading out from the point where the detonation shock and the withdrawn boundary meet. For the CJ-limit, in all cases the singular rarefaction fan eventually dominates the competition to control the steady-state behaviour. For the SRHR-limit, the spatially resolved heat release moderates this competition. When the withdrawal speed is fast, the rarefaction fan dominates; when the withdrawal speed is slower, the smooth rarefaction eventually dominates, although the flow features a fan at early times. By examining the mathematical properties of the steady two-dimensional fan-based solution, we set down a mechanism for this transition in behaviours.
This chapter addresses multicultural perspectives of intelligence in the United States. Topics include fairness in testing; environment, social location, and cultural context; measures of intelligence; and outcome implications in testing ethnocultural populations. Definitions of intelligence from a cultural perspective are highlighted. Contextual factors include: poverty, home environment, education, fluency in English, and acculturation. Testing constructs such as fairness in testing, test bias, cultural loading, and various forms of testing equivalence are discussed. Alternative assessment practices focus on nonverbal intelligence tests; dynamic assessment procedures; performance-based, authentic, and curriculum-based assessment; response to intervention, think aloud protocols, cross-battery assessment; and a multidimensional bilingual assessment model. Usage of mainstream intelligence tests is discussed in relation to Black, Asian, American Indian/Native American, and Hispanic and Latino/a communities. The numerous challenges, controversies, and complexities of interpreting test scores in cultural contexts are discussed as intelligence tests are transported, renormed, and restandardized globally.
We study the compressible flow dynamics of two-dimensional, steady detonation wave propagation in a high explosive (HE) confined by aluminium (Al) or stainless steel (SS), outside of which is an air layer. We examine how the thickness of the confinement affects the subsonic detonation driving zone structure (DDZ) and the detonation speed
, demonstrating a strong dependence on whether the oblique shock-driven flow in the confiner is supersonic, as for SS, or subsonic, as for Al. A characteristic path analysis is used to examine the information flow from the material boundaries through the supersonic flow regions in both the HE and confiner that can impact the sonic surfaces bounding the subsonic flow regions. It is shown that the nature of gas-dynamic wave reflection off the SS–air or Al–air boundary can significantly influence the DDZ and
A proportion of ex-military personnel who develop mental health and social problems end up in the Criminal Justice System. A government review called for better understanding of pathways to offending among ex-military personnel to improve services and reduce reoffending. We utilised data linkage with criminal records to examine the patterns of offending among military personnel after they leave service and the associated risk (including mental health and alcohol problems) and socio-economic protective factors.
Questionnaire data from a cohort study of 13 856 randomly selected UK military personnel were linked with national criminal records to examine changes in the rates of offending after leaving service.
All types of offending increased after leaving service, with violent offending being the most prevalent. Offending was predicted by mental health and alcohol problems: probable PTSD, symptoms of common mental disorder and aggressive behaviour (verbal, property and threatened or actual physical aggression). Reduced risk of offending was associated with post-service socio-economic factors: absence of debt, stable housing and relationship satisfaction. These factors were associated with a reduced risk of offending in the presence of mental health risk factors.
Ex-military personnel are more likely to commit violent offences after leaving service than other offence-types. Mental health and alcohol problems are associated with increased risk of post-service offending, and socio-economic stability is associated with reduced risk of offending among military veterans with these problems. Efforts to reduce post-service offending should encompass management of socio-economic risk factors as well as mental health.
Artificial linguistic systems can offer researchers test tube-like models of second language (L2) acquisition through which specific questions can be examined under tightly controlled conditions. This paper examines what research with artificial linguistic systems has revealed about the neural mechanisms involved in L2 grammar learning. It first considers the validity of meaningful and non-meaningful artificial linguistic systems. Then it contextualizes and synthesizes neural artificial linguistic system research related to questions about age of exposure to the L2, type of exposure, and online L2 learning mechanisms. Overall, using artificial linguistic systems seems to be an effective and productive way of developing knowledge about L2 neural processes and correlates. With further validation, artificial linguistic system paradigms may prove an important tool more generally in understanding how individuals learn new linguistic systems as they become bilingual.
Extending previous research that has examined the relationship between long-term memory and second language (L2) development with a primary focus on accuracy in L2 outcomes, the current study explores the relationship between declarative and procedural memory and accuracy and automatization during L2 practice. Adult English native speakers had learned an artificial language over two weeks (Morgan-Short, Faretta-Stutenberg, Brill-Schuetz, Carpenter & Wong, 2014), producing four sessions of practice data that had not been analyzed previously. Mixed-effects models analyses revealed that declarative memory was positively related to accuracy during comprehension practice. No other relationships were evidenced for accuracy. For automatization, measured by the coefficient of variation (Segalowitz, 2010), the model revealed a positive relationship with procedural memory that became stronger over practice for learners with higher declarative memory but weaker for learners with lower declarative memory. These results provide further insight into the role that long-term memory plays during L2 development.
To explore food perceptions among grandparents and understand the influence of these perceptions on food choice for the younger generations in their family.
Qualitative methodology, thematic analysis of the transcripts from fourteen focus groups.
Grandparents in the southern region of the United States.
Participants were fifty-eight Black, Hispanic, and White grandparents, predominantly women (72%), ranging in age from 44–86 years (mean age = 65·4 (sd 9·97) years).
Grandparents’ perceptions related to personal food choice were related to health issues and the media. Grandparents’ perceived influence on their children’s and grandchildren’s food choices was described through the themes of proximity and power (level of influence based on an interaction of geographic proximity to grandchildren and the power given to them by their children and grandchildren to make food decisions), healthy v. unhealthy spoiling, cultural food tradition, and reciprocal exchange of knowledge.
Our results highlight areas for future research including nutrition interventions for older adults as well as factors that may be helpful to consider when engaging grandparents concerning food decisions for younger generations to promote health. Specifically, power should be assessed as part of a holistic approach to addressing dietary influence, the term ‘healthy spoiling’ can be used to reframe notions of traditional spoiling, and the role of cultural food tradition should be adapted differently by race.
The value of decolonization as a strategy for preventing methicillin-resistantStaphylococcus aureus (MRSA) in the neonatal intensive care unit (NICU) remains to be determined.
After adding decolonization to further reduce MRSA transmission in our NICU, we conducted this retrospective review to evaluate its effectiveness.
The review included patients who were admitted to our NICU between April 2015 and June 2018 and were eligible for decolonization including twice daily intranasal mupirocin and daily chlorhexidine gluconate bathing over 5 consecutive days. Patients were considered successfully decolonized if 3 subsequent MRSA screenings conducted at 1-week intervals were negative. The MRSA acquisition rate (AR) was calculated as hospital-acquired (HA) MRSA per 1,000 patient days (PD) and was used to measure the effectiveness of the decolonization.
Of the 151 MRSA patients being reviewed, 78 (51.6%) were HA-MRSA, resulting in an overall AR of 1.27 per 1,000 PD. Between April 2015 and February 2016, when only the decolonization was added, the AR was 2.38 per 1,000 PD. Between March 2016 and June 2018 after unit added a technician dedicated to the cleaning of reusable equipment, the AR decreased significantly to 0.92 per 1,000 PD (P < .05). Of the 78 patients who were started on the decolonization, 49 (62.8%) completed the protocol, 11 (14.1%) remained colonized, and 13 (16.7%) were recolonized prior to NICU discharge.
In a NICU with comprehensive MRSA prevention measures in place, enhancing the cleaning of reusable equipment, not decolonization, led to significant reduction of MRSA transmission.
The University of São Paulo Twin Panel (Painel USP de Gêmeos), based at the Institute of Psychology of the University of São Paulo, started formally in 2017. Our registry is new, but in only two years of formal existence, it comprises a volunteer sample of 4826 registered individuals (98% twins and 2% higher-order multiples), recruited at the University of São Paulo and by social media campaigns. Our main aim is to conduct and promote research with twins on psychological processes and behavior. The University of São Paulo is the largest higher education and research institution in South America, and the Painel USP de Gêmeos has great potential for fostering research on twin-related issues from a psychological perspective in Brazil and South America.
Structure–property relationships are the foundation of materials science and are essential for predicting material response to driving forces, managing in-service material degradation, and engineering materials for optimal performance. Elastic, thermal, and acoustic properties provide a convenient gateway to directly or indirectly probe materials structure across multiple length scales. This article will review how using the laser-induced transient grating spectroscopy (TGS) technique, which uses a transient diffraction grating to generate surface acoustic waves and temperature gratings on a material surface, nondestructively reveals the material’s elasticity, thermal diffusivity, and energy dissipation on the sub-microsecond time scale, within a tunable subsurface depth. This technique has already been applied to many challenging problems in materials characterization, from analysis of radiation damage, to colloidal crystals, to phonon-mediated thermal transport in nanostructured systems, to crystal orientation and lattice parameter determination. Examples of these applications, as well as inferring aspects of microstructural evolution, illustrate the wide potential reach of TGS to solve old materials challenges and to uncover new science. We conclude by looking ahead at the tremendous potential of TGS for materials discovery and optimization when applied in situ to dynamically evolving systems.
Steady detonation in multi-dimensional flow is controlled by the chemical energy release that occurs in a subsonic elliptic flow region known as the detonation driving zone (DDZ). It is the region encompassing the detonation shock and sonic flow locus (in the frame of the detonation shock). A detonation that is strongly confined by material surrounding the explosive has the shock and sonic locus separated at the material interface. Information about the material boundary is traditionally believed to influence the DDZ structure via the subsonic flow on the boundary ahead of the sonic locus. A detonation that is weakly confined has the detonation shock and sonic locus intersecting at the material boundary. The sonic nature of the flow at the intersection point on the boundary is believed to isolate the DDZ structure from the material properties of the confinement. In this study, we examine the paths of characteristics propagating information about the confinement through the supersonic hyperbolic flow region that exists beyond the sonic locus, and determine whether these paths may impinge on the sonic locus and consequently influence the DDZ structure. Our configuration consists of a solid wall boundary deflected through a specified angle on detonation shock arrival, so that the streamline turning angle of the wall at the explosive edge is unambiguously defined. By varying the wall deflection angle from small through large values, we can systematically capture the evolution of the DDZ structure and the characteristic flow regions that influence its structure for strongly to weakly confined detonations. In all strong and weak confinement cases examined, we find that a subset of characteristics from the supersonic flow regions always impinge on the sonic locus. Limiting characteristics are identified that define the boundary between characteristics that impinge on the sonic surface and those that propagate information downstream of the sonic surface. In combination with an oblique-shock polar analysis, we show that the effects on the DDZ of characteristic impingement can be significant.
More than 1 million tons of oil is inadvertently spilled each year. The economic and environmental costs of these spills are enormous and compel further development of environmentally friendly sorbent materials. Here, we demonstrate a vapor-phase modification approach to create a new class of oil sorbents composed of cellulosic materials (cotton) coated with a subnanometer layer of inorganic oxide. This new cellulosic sorbent remains buoyant in water indefinitely and achieves a selective oil sorption capacity (23 g/g or 1.05 g/cm3) that is at least 35 times better than untreated cellulose in aqueous environments. This new sorbent particularly excels under “realistic” conditions such as continuous agitation (e.g., simulated waves) and presoaking in water (e.g., rain or forced immersion). When sorption performance is compared on a per-volume basis—which better captures use conditions than a per-mass basis—this modified natural product becomes comparable to the best sorbents reported in the literature.
The role of attention has been central to theoretical and empirical inquiries in second language (L2) acquisition. The current eye-tracking study examined how external and internal attentional manipulations (Chun, Golomb, &Turk-Browne, 2011) promote L2 grammatical development. Participants (n = 55) were exposed to Spanish direct-object pronouns under external or internal attentional manipulations, which were implemented through textual input enhancement or structured input practice, respectively. Results for both manipulations indicated that (a) learner attentional allocation to the form was affected; (b) L2 gains were evidenced, although only the internal manipulation led to above-chance performance; and (c) L2 gains were related to attention allocated to the form under the external manipulation and to a lesser extent the internal manipulation. Overall, findings may inform theoretical perspectives on attention and elucidate cognitive processes related to L2 instruction.