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Little is known about the effects of bilingualism and distributional properties of word relationships on children's development of semantic convergence, operationalized as children's ability to produce word associates that mirror adults’ responses in a word association task. Forty-five Mandarin–English bilingual, 32 Spanish–English bilingual, and 28 English-speaking monolingual children, aged 4 to 7, produced three associates to each of 15 single-word cues in English. Children's productions were compared against adult responses to the same cues in the “Small World of Words” Norm. Three scoring methods comparing similarities of children's responses to adults’ showed consistent bilingual disadvantages in producing adult-like responses. Follow-up analyses targeted the three most predominant responses adults produced for each cue and addressed factors predicting children's likelihood to produce these responses. Results showed additional effects of cue-associate relationships measured by co-occurrence and semantic relatedness. The findings highlight the multi-faceted nature of knowledge development of word relationship and semantic convergence.
In this prospective, longitudinal study, we examined the risk factors for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection among a cohort of chronic hemodialysis (HD) patients and healthcare personnel (HCPs) over a 6-month period. The risk of SARS-CoV-2 infection among HD patients and HCPs was consistently associated with a household member having SARS-CoV-2 infection.
Bison is an important and iconic mammal in the U.S. that is being reintroduced in many places after being driven nearly to extinction. This paper provides a nationwide assessment of the local economic impacts of bison reintroduction so that rural communities can take economic well-being into account when considering decisions regarding future bison restorations. We estimate the causal impacts of bison herd establishment on county-level income, employment, and population growth using staggered difference-in-difference and the synthetic control approaches. The simple positive correlation between local per capita income and bison herds might lead planners to think that bison reintroduction is good for the local economy. However, none of the causal inference analyses find statistically significant effects of bison reintroduction.
We explore the interior stratification that develops in a reservoir of fluid in which there is a localised source of destabilising (positive) buoyancy and a distributed source of stabilising (negative) buoyancy at the surface of the fluid, combined with an interior turbulent diffusivity. The source of destabilising buoyancy forms a descending turbulent plume that entrains ambient fluid, and this, coupled with the interior turbulent diffusivity, leads to mixing of the interior fluid. When the ratio $Pe$ of the plume source volume flux to the diffusive flux across the whole reservoir is large, the reservoir is well mixed except for a narrow surface boundary layer, while for smaller $Pe$, the reservoir is more stratified, consistent with the results of Hughes et al. (J. Fluid Mech., vol. 581, 2007, pp. 251–276) and Hughes & Griffiths (Annu. Rev. Fluid Mech., vol. 40, issue 1, 2008, pp. 185–208). We explore the evolution of the system when the source buoyancy flux varies in time, exploring both sudden changes and oscillatory changes in the forcing. Provided that the time scale of the change in the forcing is comparable to or smaller than the response time of the reservoir, as the source buoyancy flux decreases the plume may become trapped in the upper part of the reservoir, leading to a much shallower mixed zone. However, in the case of a source whose strength oscillates in time, as the source buoyancy flux increases, again the deeper water becomes involved in the mixing and circulation. We discuss briefly how these results may provide insight into the impact of changes in the forcing on mixing in deep ocean waters.
Organ donation after brain death has been practiced in China since 2003 in the absence of brain death legislation. Similar to international standards, China’s brain death diagnostic criteria include coma, absence of brainstem reflexes, and the lack of spontaneous respiration. The Chinese criteria require that the lack of spontaneous respiration must be verified with an apnea test by disconnecting the ventilator for 8 min to provoke spontaneous respiration. However, we have found publications in Chinese medical journals, in which the donors were declared to be brain dead, yet without an apnea test. The organ procurement procedures started with initiating “intratracheal intubation for mechanical ventilation after brain death,” indicating that a brain death diagnosis was not performed. The purpose of the intubation was not to resuscitate the patient but rather was directly related to facilitating the explantation of organs. Moreover, it was unmistakably stated in two of these publications that the cardiac arrest was induced in these patients without brain death determination by cold St. Thomas cardioplegic solution or other cold myocardial protection solutions. This means that the condition of these donors neither met the criteria of brain death nor that of cardiac death. In other words, the “donor organs” may well have been procured in these cases from living human beings. Thus, brain death definition is abused in China by some individuals for organ harvesting, and a systematic investigation is needed to clarify the situation of organ donation after brain death in China.
Ionising radiotherapy is a well-established, effective cancer treatment modality, whose efficacy has improved with the application of newer technological modalities. However, patient outcomes are governed and potentially limited by aspects of tumour biology that are associated with radioresistance. Patients also still endure treatment-associated toxicities owed to the action of ionising radiation in normoxic tissue adjacent to the tumour mass. Tumour hypoxia is recognised as a key component of the tumour microenvironment and is well established as leading to therapy resistance and poor prognosis. In this review, we outline the current understanding of hypoxia-mediated radiotherapy resistance, before exploring targeting tumour hypoxia for radiotherapy sensitisation to improve treatment outcomes and increase the therapeutic window. This includes increasing oxygen availability in solid tumours, the use of hypoxia-activated prodrugs, targeting of hypoxia-regulated or associated signalling pathways, as well as the use of high-LET radiotherapy modalities. Ultimately, targeting hypoxic radiobiology combined with precise radiotherapy delivery modalities and modelling should be associated with improvement to patient outcomes.
The incidence of scarlet fever has increased dramatically in recent years in Chongqing, China, but there has no effective method to forecast it. This study aimed to develop a forecasting model of the incidence of scarlet fever using a seasonal autoregressive integrated moving average (SARIMA) model. Monthly scarlet fever data between 2011 and 2019 in Chongqing, China were retrieved from the Notifiable Infectious Disease Surveillance System. From 2011 to 2019, a total of 5073 scarlet fever cases were reported in Chongqing, the male-to-female ratio was 1.44:1, children aged 3–9 years old accounted for 81.86% of the cases, while 42.70 and 42.58% of the reported cases were students and kindergarten children, respectively. The data from 2011 to 2018 were used to fit a SARIMA model and data in 2019 were used to validate the model. The normalised Bayesian information criterion (BIC), the coefficient of determination (R2) and the root mean squared error (RMSE) were used to evaluate the goodness-of-fit of the fitted model. The optimal SARIMA model was identified as (3, 1, 3) (3, 1, 0)12. The RMSE and mean absolute per cent error (MAPE) were used to assess the accuracy of the model. The RMSE and MAPE of the predicted values were 19.40 and 0.25 respectively, indicating that the predicted values matched the observed values reasonably well. Taken together, the SARIMA model could be employed to forecast scarlet fever incidence trend, providing support for scarlet fever control and prevention.
For a common micro-satellite, orbiting in a circular sun-synchronous orbit (SSO) at an altitude between 500 and 600km, the satellite attitude during off-nadir imaging and staring-imaging operations can be up to ±45 degree on roll and pitch angles. During these off-nadir pointing for both multi-trip operation and staring imaging operations, the spacecraft body is commonly subject to high-rate motion. This posts challenges for a spacecraft attitude determination subsystem called Gyro Stellar Inertial Attitude Estimate (GS IAE), which employs gyros and star sensors to maintain the required attitude knowledge, since star trackers will severely degrade attitude estimation accuracies when the spacecraft is subject to high-rate motion. This paper analyses the star motion-induced errors for a typical star tracker, models the star motion-induced errors to assess the performance impact on the attitude estimation accuracy, and investigates the adaptive extended Kalman filter design in the GS IAE while evaluating its effectiveness.
Children undergoing cardiac surgery have overall improving survival, though they consume substantial resources. Nationwide inpatient cost estimates and costs at longitudinal follow-up are lacking.
Retrospective cohort study of children <19 years of age admitted to Pediatric Health Information System administrative database with an International Classification of Diseases diagnosis code undergoing cardiac surgery. Patients were grouped into neonates (≤30 days of age), infants (31–365 days of age), and children (>1 year) at index procedure. Primary and secondary outcomes included hospital stay and hospital costs at index surgical admission and 1- and 5-year follow-up.
Of the 99,670 cohort patients, neonates comprised 27% and had the highest total hospital costs, though daily hospital costs were lower. Mortality declined (5.6% in 2004 versus 2.5% in 2015, p < 0.0001) while inpatient costs rose (5% increase/year, p < 0.0001). Neonates had greater index diagnosis complexity, greater inpatient costs, required the greatest ICU resources, pharmacotherapy, and respiratory therapy. We found no relationship between hospital surgical volume, mortality, and hospital costs. Neonates had higher cumulative hospital costs at 1- and 5-year follow-up compared to infants and children.
Inpatient hospital costs rose during the study period, driven primarily by longer stay. Neonates had greater complexity index diagnosis, required greater hospital resources, and have higher hospital costs at 1 and 5 years compared to older children. Surgical volume and in-hospital mortality were not associated with costs. Further analyses comprising merged clinical and administrative data are necessary to identify longer stay and cost drivers after paediatric cardiac surgery.
Patients on dialysis are at high risk for severe COVID-19 and associated morbidity and mortality. We examined the humoral response to SARS-CoV-2 mRNA vaccine BNT162b2 in a maintenance dialysis population.
Single-center cohort study.
Setting and participants:
Adult maintenance dialysis patients at 3 outpatient dialysis units of a large academic center.
Participants were vaccinated with 2 doses of BNT162b2, 3 weeks apart. We assessed anti–SARS-CoV-2 spike antibodies (anti-S) ∼4–7 weeks after the second dose and evaluated risk factors associated with insufficient response. Definitions of antibody response are as follows: nonresponse (anti-S level, <50 AU/mL), low response (anti-S level, 50–839 AU/mL), and sufficient response (anti-S level, ≥840 AU/mL).
Among the 173 participants who received 2 vaccine doses, the median age was 60 years (range, 28–88), 53.2% were men, 85% were of Black race, 86% were on in-center hemodialysis and 14% were on peritoneal dialysis. Also, 7 participants (4%) had no response, 27 (15.6%) had a low response, and 139 (80.3%) had a sufficient antibody response. In multivariable analysis, factors significantly associated with insufficient antibody response included end-stage renal disease comorbidity index score ≥5 and absence of prior hepatitis B vaccination response.
Although most of our study participants seroconverted after 2 doses of BNT162b2, 20% of our cohort did not achieve sufficient humoral response. Our findings demonstrate the urgent need for a more effective vaccine strategy in this high-risk patient population and highlight the importance of ongoing preventative measures until protective immunity is achieved.
Maternal obesity programs the offspring to metabolic diseases later in life; however, the mechanisms of programming are yet unclear, and no strategies exist for addressing its detrimental transgenerational effects. Obesity has been linked to dipeptidyl peptidase IV (DPPIV), an adipokine, and treatment of obese individuals with DPPIV inhibitors has been reported to prevent weight gain and improve metabolism. We hypothesized that DPPIV plays a role in maternal obesity-mediated programming. We measured plasma DPPIV activity in human maternal and cord blood samples from normal-weight and obese mothers at term. We found that maternal obesity increases maternal and cord blood plasma DPPIV activity but only in male offspring. Using two non-human primate models of maternal obesity, we confirmed the activation of DPPIV in the offspring of obese mothers. We then created a mouse model of maternal high-fat diet (HFD)-induced obesity, and found an early-life increase in plasma DPPIV activity in male offspring. Activation of DPPIV preceded the progression of obesity, glucose intolerance and insulin resistance in male offspring of HFD-fed mothers. We then administered sitagliptin, DPPIV inhibitor, to regular diet (RD)- and HFD-fed mothers, starting a week prior to breeding and continuing throughout pregnancy and lactation. We found that sitagliptin treatment of HFD-fed mothers delayed the progression of obesity and metabolic diseases in male offspring and had no effects on females. Our findings reveal that maternal obesity dysregulates plasma DPPIV activity in males and provide evidence that maternal inhibition of DPPIV has potential for addressing the transgenerational effects of maternal obesity.
While ethics has been identified as a core component of health technology assessment (HTA), there are few examples of practical, systematic inclusion of ethics analysis in HTA. Some attribute the scarcity of ethics analysis in HTA to debates about appropriate methodology and the need for ethics frameworks that are relevant to local social values. The “South African Values and Ethics for Universal Health Coverage” (SAVE-UHC) project models an approach that countries can use to develop HTA ethics frameworks that are specific to their national contexts.
The SAVE-UHC approach consisted of two phases. In Phase I, the research team convened and facilitated a national multistakeholder working group to develop a provisional ethics framework through a collaborative, engagement-driven process. In Phase II, the research team refined the model framework by piloting it through three simulated HTA appraisal committee meetings. Each simulated committee reviewed two case studies of sample health interventions: opioid substitution therapy and either a novel contraceptive implant or seasonal influenza immunization for children under five.
The methodology was fit-for-purpose, resulting in a context-specified ethics framework and producing relevant findings to inform application of the framework for the given HTA context.
The SAVE-UHC approach provides a model for developing, piloting, and refining an ethics framework for health priority-setting that is responsive to national social values. This approach also helps identify key facilitators and challenges for integrating ethics analysis into HTA processes.
Heating of over-dense plasma represents a long-standing quest in laser–plasma physics. When the strength of the magnetic field is above the critical value, a right-handed circularly polarized laser could propagate into and heat up the highly magnetized over-dense collisional plasma directly; the processes are dependent on the parameters of the laser, plasma and magnetic field. The parametric dependence is fully studied both qualitatively and quantitatively, resulting in scaling laws of the plasma temperature, heating depth and energy conversion efficiency. Such heating is also studied with the most powerful CO2 and strongest magnetic field in the world, where plasma with density of
cm–3 and initial temperature of 1 keV is heated to around 10 keV within a depth of several micrometres. Several novel phenomena are also discovered and discussed, that is, local heating in the region of high density, low temperature or weak magnetic field.
The cosmic evolution of the chemical elements from the Big Bang to the present time is driven by nuclear fusion reactions inside stars and stellar explosions. A cycle of matter recurrently re-processes metal-enriched stellar ejecta into the next generation of stars. The study of cosmic nucleosynthesis and this matter cycle requires the understanding of the physics of nuclear reactions, of the conditions at which the nuclear reactions are activated inside the stars and stellar explosions, of the stellar ejection mechanisms through winds and explosions, and of the transport of the ejecta towards the next cycle, from hot plasma to cold, star-forming gas. Due to the long timescales of stellar evolution, and because of the infrequent occurrence of stellar explosions, observational studies are challenging, as they have biases in time and space as well as different sensitivities related to the various astronomical methods. Here, we describe in detail the astrophysical and nuclear-physical processes involved in creating two radioactive isotopes useful in such studies,
. Due to their radioactive lifetime of the order of a million years, these isotopes are suitable to characterise simultaneously the processes of nuclear fusion reactions and of interstellar transport. We describe and discuss the nuclear reactions involved in the production and destruction of
, the key characteristics of the stellar sites of their nucleosynthesis and their interstellar journey after ejection from the nucleosynthesis sites. This allows us to connect the theoretical astrophysical aspects to the variety of astronomical messengers presented here, from stardust and cosmic-ray composition measurements, through observation of
rays produced by radioactivity, to material deposited in deep-sea ocean crusts and to the inferred composition of the first solids that have formed in the Solar System. We show that considering measurements of the isotopic ratio of
eliminate some of the unknowns when interpreting astronomical results, and discuss the lessons learned from these two isotopes on cosmic chemical evolution. This review paper has emerged from an ISSI-BJ Team project in 2017–2019, bringing together nuclear physicists, astronomers, and astrophysicists in this inter-disciplinary discussion.
South-east Asia's diverse coastal wetlands, which span natural mudflats and mangroves to man-made salt pans, offer critical habitat for many migratory waterbird species in the East Asian–Australasian Flyway. Species dependent on these wetlands include nearly the entire population of the Critically Endangered spoon-billed sandpiper Calidris pygmaea and the Endangered spotted greenshank Tringa guttifer, and significant populations of several other globally threatened and declining species. Presently, more than 50 coastal Important Bird and Biodiversity Areas (IBAs) in the region (7.4% of all South-east Asian IBAs) support at least one threatened migratory species. However, recent studies continue to reveal major knowledge gaps on the distribution of migratory waterbirds and important wetland sites along South-east Asia's vast coastline, including undiscovered and potential IBAs. Alongside this, there are critical gaps in the representation of coastal wetlands across the protected area networks of many countries in this region (e.g. Viet Nam, Indonesia, Malaysia), hindering effective conservation. Although a better understanding of the value of coastal wetlands to people and their importance to migratory species is necessary, governments and other stakeholders need to do more to strengthen the conservation of these ecosystems by improving protected area coverage, habitat restoration, and coastal governance and management. This must be underpinned by the judicious use of evidence-based approaches, including satellite-tracking of migratory birds, ecological research and ground surveys.
Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools.
To examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics.
Genome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts.
Earlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = −0.34 years, s.e. = 0.08), major depression (β = −0.34 years, s.e. = 0.08), schizophrenia (β = −0.39 years, s.e. = 0.08), and educational attainment (β = −0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO.
AAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.