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The two most influential models in delay discounting research have been the exponential (E) and hyperbolic (H) models. We develop a new methodology to design binary choice questions such that exponential and hyperbolic discount rates can be purposefully manipulated to make their rate parameters orthogonal (Pearson’s R = 0), negatively correlated (R = –1), positively correlated (R = +1), or to hold one rate constant while allowing the other to vary. Then we extend the method to similarly contrast different versions of the hyperboloid model. The arithmetic discounting model (A), which is based on differences between present and future rewards rather than their ratios, may easily be made orthogonal to any other pair of models. Our procedure makes it possible to design choice stimuli that precisely vary the relationship between different discount rates. However, the additional control over the correlation between different discount rate parameters may require the researcher to either restrict the range that those rate parameters can take, or to expand the range of times the participant must wait for future rewards.
The transition from residency to paediatric cardiology fellowship is challenging due to the new knowledge and technical skills required. Online learning can be an effective didactic modality that can be widely accessed by trainees. We sought to evaluate the effectiveness of a paediatric cardiology Fellowship Online Preparatory Course prior to the start of fellowship.
The Online Preparatory Course contained 18 online learning modules covering basic concepts in anatomy, auscultation, echocardiography, catheterisation, cardiovascular intensive care, electrophysiology, pulmonary hypertension, heart failure, and cardiac surgery. Each online learning module included an instructional video with pre-and post-video tests. Participants completed pre- and post-Online Preparatory Course knowledge-based exams and surveys. Pre- and post-Online Preparatory Course survey and knowledge-based examination results were compared via Wilcoxon sign and paired t-tests.
151 incoming paediatric cardiology fellows from programmes across the USA participated in the 3 months prior to starting fellowship training between 2017 and 2019. There was significant improvement between pre- and post-video test scores for all 18 online learning modules. There was also significant improvement between pre- and post-Online Preparatory Course exam scores (PRE 43.6 ± 11% versus POST 60.3 ± 10%, p < 0.001). Comparing pre- and post-Online Preparatory Course surveys, there was a statistically significant improvement in the participants’ comfort level in 35 of 36 (97%) assessment areas. Nearly all participants (98%) agreed or strongly agreed that the Online Preparatory Course was a valuable learning experience and helped alleviate some anxieties (77% agreed or strongly agreed) related to starting fellowship.
An Online Preparatory Course prior to starting fellowship can provide a foundation of knowledge, decrease anxiety, and serve as an effective educational springboard for paediatric cardiology fellows.
To determine the association between delay in transfer to a central stroke unit from peripheral institutions and outcomes.
We conducted a retrospective cohort study of all patients with acute stroke, admitted to a comprehensive stroke center (CSC) from three emergency departments (EDs), between 2016 and 2018. The primary outcomes were length of stay, functional status at 3 months, discharge destination, and time to stroke investigations.
One thousand four hundred thirty-five patients were included, with a mean age of 72.9 years, and 92.4% ischemic stroke; 663 (46.2%) patients were female. Each additional day of delay was associated with 2.0 days of increase in length of stay (95% confidence interval [CI] 0.8–3.2, p = 0.001), 11.5 h of delay to vascular imaging (95% CI 9.6–13.4, p < 0.0001), 24.2 h of delay to Holter monitoring (95% CI 7.9–40.6, p = 0.004), and reduced odds of nondisabled functional status at 3 months (odds ratio 0.98, 95% CI 0.96–1.00, p = 0.01). Factors affecting delay included stroke onset within 6 h of ED arrival (605.9 min decrease in delay, 95% CI 407.9–803.9, p < 0.0001), delay to brain imaging (59.4 min increase in delay for each additional hour, 95% CI 48.0–71.4, p < 0.0001), admission from an alternative service (3918.7 min increase in delay, 95% CI 3621.2–4079.9, p < 0.0001), and transfer from a primary stroke center (PSC; 740.2 min increase in delay, 95% CI 456.2–1019.9, p < 0.0001).
Delay to stroke unit admission in a system involving transfer from PSCs to a CSC was associated with longer hospital stay and poorer functional outcomes.
Early adversity confers risk for depression in part through its association with recent (i.e., proximal) acute stress. However, it remains unresolved whether: a) early adversity predicts increases in recent acute stress over time; b) all – or only certain types – of recent events mediate the relationship between early adversity and depression; and c) early adversity places individuals at greater risk for depression via greater exposure to independent (i.e., fateful) interpersonal events or via greater generation of dependent (i.e., partially self-initiated) interpersonal events (i.e., stress generation) or both. These questions were examined in a 3-wave longitudinal study of early adolescent girls (N = 125; M = 12.35 years [SD = .77]) with no history of diagnosable depression using contextual life stress and diagnostic interviews. Path analyses indicated that increases in past-year acute interpersonal, but not non-interpersonal, stress mediated the link between early adversity and depressive symptoms. The mediating role of interpersonal events was limited to independent ones, suggesting increases in interpersonal event exposure, not interpersonal stress generation, acted as a mediator. Finally, findings support prior evidence that early adversity may not directly predict future depressive symptoms. Implications for understanding the role of recent stress in the association between early adversity and adolescent depression are discussed.
Schistosomiasis has been subjected to extensive control efforts in the People's Republic of China (China) which aims to eliminate the disease by 2030. We describe baseline results of a longitudinal cohort study undertaken in the Dongting and Poyang lakes areas of central China designed to determine the prevalence of Schistosoma japonicum in humans, animals (goats and bovines) and Oncomelania snails utilizing molecular diagnostics procedures. Data from the Chinese National Schistosomiasis Control Programme (CNSCP) were compared with the molecular results obtained.
Sixteen villages from Hunan and Jiangxi provinces were surveyed; animals were only found in Hunan. The prevalence of schistosomiasis in humans was 1.8% in Jiangxi and 8.0% in Hunan determined by real-time polymerase chain reaction (PCR), while 18.3% of animals were positive by digital droplet PCR. The CNSCP data indicated that all villages harboured S. japonicum-infected individuals, detected serologically by indirect haemagglutination assay (IHA), but very few, if any, of these were subsequently positive by Kato-Katz (KK).
Based on the outcome of the IHA and KK results, the CNSCP incorporates targeted human praziquantel chemotherapy but this approach can miss some infections as evidenced by the results reported here. Sensitive molecular diagnostics can play a key role in the elimination of schistosomiasis in China and inform control measures allowing for a more systematic approach to treatment.
Little is known about the effects of physical exercise on sleep-dependent consolidation of procedural memory in individuals with schizophrenia. We conducted a randomized controlled trial (RCT) to assess the effectiveness of physical exercise in improving this cognitive function in schizophrenia.
A three-arm parallel open-labeled RCT took place in a university hospital. Participants were randomized and allocated into either the high-intensity-interval-training group (HIIT), aerobic-endurance exercise group (AE), or psychoeducation group for 12 weeks, with three sessions per week. Seventy-nine individuals with schizophrenia spectrum disorder were contacted and screened for their eligibility. A total of 51 were successfully recruited in the study. The primary outcome was sleep-dependent procedural memory consolidation performance as measured by the finger-tapping motor sequence task (MST). Assessments were conducted during baseline and follow-up on week 12.
The MST performance scored significantly higher in the HIIT (n = 17) compared to the psychoeducation group (n = 18) after the week 12 intervention (p < 0.001). The performance differences between the AE (n = 16) and the psychoeducation (p = 0.057), and between the AE and the HIIT (p = 0.999) were not significant. Yet, both HIIT (p < 0.0001) and AE (p < 0.05) showed significant within-group post-intervention improvement.
Our results show that HIIT and AE were effective at reverting the defective sleep-dependent procedural memory consolidation in individuals with schizophrenia. Moreover, HIIT had a more distinctive effect compared to the control group. These findings suggest that HIIT may be a more effective treatment to improve sleep-dependent memory functions in individuals with schizophrenia than AE alone.
In this paper, we use finite element analysis (FEA) to study the linear viscoelastic response of polyurea, a type of hard–soft block copolymer. A Niblack's algorithm-based technique employed on atomic force microscopy images provides geometry inputs for the FEA model, while the viscoelastic master curves of the soft matrix are obtained via a combination of dynamic mechanical analysis data and molecular dynamic (MD) estimations. In this microstructural image-based FEA framework, we introduce an interphase area of altered properties between the hard and soft domains. Both spatial and property distributions of this interphase area affect the viscoelastic response of the copolymer system. To quantitatively investigate the impact of structural and property features of the interphase on the energy storage and dissipation of a system during linear perturbation, we develop a statistical descriptor representation of the interphase region related to physical parameters. Utilizing decision-tree and random forest concepts from machine learning, we apply a ranking algorithm to identify the most significant features for four different mechanical response descriptors. Results show that the total interphase volume fraction and shifting factor distributions in the interphase area dominate the magnitude of the tan δ peak, whereas the magnitudes of the shifting factors primarily affect the tan δ peak location in frequency space. This method allows us to readily identify the dominant features impacting individual properties and paves the way for material design of hard–soft block copolymer systems.
The foetal programming hypothesis posits that optimising early life factors e.g. maternal diets can help avert the burden of adverse childhood outcomes e.g. childhood obesity. To improve applicability to public health messaging, we investigated whether maternal whole diet quality and inflammatory potential influence childhood adiposity in a large consortium.
We harmonized and pooled individual participant data from up to 8,769 mother-child pairs in 7 European mother-offspring cohorts. Maternal early-, late-, and whole-pregnancy dietary quality and inflammatory potential were assessed with Dietary Approaches to Stop Hypertension (DASH) and energy-adjusted Dietary Inflammatory Index (E-DII), respectively. Primary outcome was childhood overweight and obesity (OWOB), defined as age- and sex-specific body-mass-index-z score (BMIz) > 85th percentile based on WHO growth standard. Secondary outcomes were sum-of-skinfold-thickness (SST), fat-mass-index (FMI) and fat-free-mass-index (FFMI) in available cohorts. Outcomes were assessed in early- [mean (SD) age: 2.8 (0.3) y], mid- [6.2 (0.6) y], and late-childhood [10.6 (1.2) y]. We used multivariable regression analyses to assess the associations of maternal E-DII and DASH with offspring adiposity outcomes in cohort-specific analyses, with subsequent random-effects meta-analyses. Analyses were adjusted for maternal age, pre-pregnancy BMI, parity, lifestyle factors, energy intake, educational attainment, offspring age and sex.
A more pro-inflammatory maternal diet, indicated by higher E-DII, was associated with a higher risk of offspring late-childhood OWOB [pooled-OR (95% CI) comparing highest vs. lowest E-DII quartiles: 1.22 (1.01,1.47) for whole-pregnancy and 1.38 (1.05,1.83) for early-pregnancy; both P < 0.05]. Moreover, higher late-pregnancy E-DII was associated with higher mid-childhood FMI [pooled-β (95% CI): 0.11 (0.003,0.22) kg/m2; P < 0.05]; trending association was observed for whole-pregnancy E-DII [0.12 (-0.01,0.25) kg/m2; P = 0.07]. A higher maternal dietary quality, indicated by higher DASH score, showed a trending inverse association with late-childhood OWOB (pooled-OR (95% CI) comparing highest vs. lowest DASH quartiles: 0.58 (0.32,1.02; P = 0.06). Higher early-pregnancy DASH was associated with lower late-childhood SST [pooled-β (95% CI): -1.9 (-3.6,-0.1) cm; P < 0.05] and tended to be associated with lower late-childhood FMI [-0.34 (-0.71,0.04) kg/m2; P = 0.08]. Higher whole-pregnancy DASH tended to associate with lower early-childhood SST [-0.33 (-0.72,0.06) cm; P = 0.10]. Results were similar when modelling DASH and E-DII continuously.
Analysis of pooled data suggests that pro-inflammatory, low-quality maternal antenatal diets may influence offspring body composition and obesity risk, especially during mid- or late-childhood. Due to variation of data availability at each timepoint, our results should be interpreted with caution. Because most associations were observed at mid-childhood or later, future studies will benefit from a longer follow-up.
Studies suggest that d-cycloserine (DCS) may have antidepressant potential through its interaction with the glycine site of the N-methyl-D-aspartate receptor; however, clinical evidence of DCS's efficacy as a treatment for depression is limited. Other evidence suggests that DCS affects emotional learning which may also be relevant for the treatment of depression and anxiety. The aim of the present investigation was to assess the effect of DCS on emotional processing in healthy volunteers and to further characterise its effects on emotional and autobiographical memory.
Forty healthy volunteers were randomly allocated to a single dose of 250 mg DCS or placebo in a double-blind design. Three hours later, participants performed an Emotional Test Battery [including Facial Expression Recognition Task (FERT), Emotional Categorisation Task (ECAT), Emotional Recall Task (EREC), Facial Dot-Probe Task (FDOT) and Emotional Recognition Memory Task (EMEM)] and an Autobiographical Memory Test (AMT). Also, participants performed the FERT, EREC and AMT tasks again after 24 h in order to assess longer lasting effects of a single dose of DCS.
DCS did not significantly affect the FERT, EMEM and FDOT performance but significantly increased emotional memory and classification for positive words v. negative words. Also, DCS enhanced the retrieval of more specific autobiographical memories, and this effect persisted at 24 h.
These findings support the suggestion that low-dose DCS increases specific autobiographical memory retrieval and positive emotional memory. Such effects make it an intriguing agent for further investigation in clinical depression, which is characterised by decreased autobiographical memory specificity and increased negative bias in memory recall. It also underscores the potential role of DCS as an adjunct to cognitive behavioural therapy in depression.
The Earth is dramatically carbon poor comparing to the interstellar medium and the proto-sun. The carbon to silicon ratios in inner solar system objects show a correlation with heliocentric distance, which suggests that the destruction of carbon grains has occurred before planet formation. To examine this hypothesis, we perform model calculations using a chemical reaction network under the physical conditions typical of protoplanetary disks. Our results show that, when carbonaceous grains are destroyed and converted into the gas phase and the gas becomes carbon-rich, the abundances of carbon-bearing species such as HCN and carbon-chain molecules, increase dramatically near the midplane, while oxygen-bearing species such as H2O and CO2 are depleted. The carbon to silicon ratios obtained by our model calculations qualitatively reproduce the observed gradient with disk radius, but there are some quantitative discrepancies from the observed values of the solar system objects. We adopted the model of a disk around a Herbig Ae star and performed line radiative transfer calculations to examine the effect of carbon grain destruction through observations with ALMA. The results indicate that HCN, H13 CN and c-C3 H2 may be good tracers of this process.
Research suggests that early adversity places individuals at risk for psychopathology across the life span. Guided by concepts of allostasis and allostatic load, the present study examined whether early adversity contributes to the development of subsequent internalizing symptoms through its association with traitlike individual differences in hypothalamic–pituitary–adrenal axis regulation. Early adolescent girls (n = 113; M age = 12.30 years) provided saliva samples at waking, 30 min postwaking, and bedtime over 3 days (later assayed for cortisol). Objective contextual stress interviews with adolescents and their mothers were used to assess the accumulation of nine types of early adversity within the family environment. Greater early adversity predicted subsequent increases in internalizing symptoms through lower levels of latent trait cortisol. Traitlike individual differences in hypothalamic–pituitary–adrenal axis activity may be among the mechanisms through which early adversity confers risk for the development of psychopathology.
Local crystal structure, crystal orientation, and crystal deformation can all be probed by Laue diffraction using a submicron x-ray beam. This technique, employed at a synchrotron facility, is particularly suitable for fast mapping the mechanical and microstructural properties of inhomogeneous multiphase polycrystalline samples, as well as imperfect epitaxial films or crystals. As synchrotron Laue x-ray microdiffraction enters its 20th year of existence and new synchrotron nanoprobe facilities are being built and commissioned around the world, we take the opportunity to overview current capabilities as well as the latest technical developments. Fast data collection provided by state-of-the-art area detectors and fully automated pattern indexing algorithms optimized for speed make it possible to map large portions of a sample with fine step size and obtain quantitative images of its microstructure in near real time. We extrapolate how the technique is anticipated to evolve in the near future and its potential emerging applications at a free-electron laser facility.
To describe and compare the mortality associated with nosocomial pneumonia due to Pseudomonas aeruginosa (Pa-NP) according to pneumonia classification (community-onset pneumonia [COP], hospital-acquired pneumonia [(HAP], and ventilator-associated pneumonia [VAP]).
We conducted a retrospective cohort study of adults with Pa-NP. We compared mortality for Pa-NP among patients with COP, HAP, and VAP and used logistic regression to identify risk factors for hospital mortality and inappropriate initial antibiotic therapy (IIAT).
Twelve acute care hospitals in 5 countries (United States, 3; France, 2; Germany, 2; Italy, 2; and Spain, 3).
A total of 742 patients with Pa-NP.
Hospital mortality was greater for those with VAP (41.9%) and HAP (40.1%) compared with COP (24.5%) (P<.001). In multivariate analyses, independent predictors of hospital mortality differed by pneumonia classification (COP: need for mechanical ventilation and intensive care; HAP: multidrug-resistant isolate; VAP: IIAT, increasing age, increasing Charlson comorbidity score, bacteremia, and use of vasopressors). Presence of multidrug resistance was identified as an independent predictor of IIAT for patients with COP and HAP, whereas recent antibiotic administration was protective in patients with VAP.
Among patients with Pa-NP, pneumonia classification identified patients with different risks for hospital mortality. Specific risk factors for hospital mortality also differed by pneumonia classification and multidrug resistance appeared to be an important risk factor for IIAT. These findings suggest that pneumonia classification for P. aeruginosa identifies patients with different mortality risks and specific risk factors for outcome and IIAT.
Infect Control Hosp Epidemiol 2015;36(10):1190–1197
DHA is an abundant nutrient from marine lipids: its specific biological effects have been investigated in human volunteers, taking into consideration the dose effects. We report herein that, at dosages below 1 g/d, DHA proved to be effective in lowering blood platelet function and exhibited an ‘antioxidant’ effect. However, this was no longer the case following 1·6 g/d, showing then a U-shape response. The antioxidant effect has been observed in platelets as well as LDL, of which the redox status is assumed to be crucial in their relationship with atherosclerosis. Second, the oxygenated products of DHA, especially protectins produced by lipoxygenases, have been considered for their potential to affect blood platelets and leucocytes. It is concluded that DHA is an interesting nutrient to reduce atherothrombogenesis, possibly through complementary mechanisms involving lipoxygenase products of DHA.