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 email@example.com
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.
To understand the complex relationships between autism spectrum disorder (ASD) and other frequently comorbid conditions, a growing number of studies have investigated the emergence of ASD during infancy. This research has suggested that symptoms of ASD and highly related comorbid conditions emerge from complex interactions between neurodevelopmental vulnerabilities and early environments, indicating that developing treatments to prevent ASD is highly challenging. However, it also suggests that attenuating the negative effects of ASD on future development once identified is possible. The present paper builds on this by conceptualizing developmental delays in nonsocial skills as the potential product of altered caregiver–infant interactions following the emergence of ASD during infancy. And, following emerging findings from caregiver–infant dyadic head-mounted eye-tracking (D-ET) research, it also suggests that a multiple pathway model of joint attention can provide mechanistic insights into how ASD alters the ability of caregiver and infant to create a context for infant learning. The potential for this view to inform early intervention is further discussed and illustrated through D-ET data collected prior to and following a brief, parent-mediated intervention for infant ASD. While promising, further research informing how a multiple pathway model of joint attention can inform ASD early intervention is needed.
Little is known about methylphenidate (MPH) use and mortality outcomes.
To investigate the association between MPH use and mortality among children with an attention-deficit hyperactivity disorder (ADHD) diagnosis.
This population-based cohort study analysed data from Taiwan's National Health Insurance Research Database (NHIRD). A total of 68 096 children and adolescents aged 4–17 years with an ADHD diagnosis and prescribed MPH between 2000 and 2010 were compared with 68 096 without an MPH prescription, matched on age, gender and year of first ADHD diagnosis. All participants were followed to death, migration, withdrawal from the National Health Insurance programme or 31 December 2013. MPH prescriptions were measured on a yearly basis during the study period, and the association between MPH use and mortality was analysed using a repeated-measures time-dependent Cox regression model. The outcome measures included all-cause, unnatural-cause (including suicide, accident and homicide) and natural-cause mortality, obtained from linkage to the National Mortality Register in Taiwan.
The MPH group had lower unadjusted all-cause, natural-, unnatural- and accident-cause mortality than the comparison group. After controlling for potential confounders, MPH use was associated with a significantly lower all-cause mortality (adjusted hazard ratio AHR = 0.81, 95% CI 0.67–0.98, P = 0.027), delayed use of MPH was associated with higher mortality (AHR = 1.05, 95% CI 1.01–1.09) and longer MPH use was associated with lower mortality (AHR = 0.83, 95% CI 0.70–0.98).
MPH use is associated with a reduced overall mortality in children with ADHD in this cohort study, but unmeasured confounding cannot be excluded absolutely.
Optical Photothermal Infrared (O-PTIR) spectroscopy is a new technique for measuring submicron spatial resolution IR spectra with little or no sample preparation. This speeds up analysis times benefiting high-volume manufacturers through gaining insight into process contamination that occurs during development and on production lines. The ability to rapidly obtain far-field non-contact IR spectra at high spatial resolution facilitates the chemical identification of small organic contaminants that are not possible to measure with conventional Fourier transform infrared (FT-IR) microspectroscopy. The unique pump-probe system architecture also facilitates submicron simultaneous IR + Raman microscopy from the same spot with the same spatial resolution. With these unique capabilities, O-PTIR is finding utilization in the high-volume and high-value industries of high-tech componentry (memory storage, electronics, displays, etc.).
Anxiety and depression are distinct clinical entities associated with mortality in haemodialysis (HD) patients.
This study aims to identify the prevalence of anxiety and depression in HD patients and uncover the association of anxiety and depression in relation to the dialysis adequacy and nutritional status.
This would help reinforce early detection and treatment to improve quality of life and patient's outcome in HD treatment.
Forty HD patients were assessed for anxiety and depression with the Generalised Anxiety Disorder Assessment (GAD-7 and Patient Health Questionaire [PHQ-9]). The scores of GAD-7 and PHQ-9 were correlated with the demographic, clinical and laboratory variables and nutritional status assessed by a dietician through the Subjective Global Assessment (SGA).
Out of the 40 HD patients, 7 (17.5%) were anxious and 15 (37.5%) were depressed. Patients were more anxious and less depressed with better nutrition. They were less anxious and depressed with increasing albumin levels, Charlston comorbidity index based on combined condition and age-related score and Kt/V. The univariate logistic regression analysis showed only a significant inverse correlation between depression and albumin level (P = 0.041, OR = 0.88 [95% CI = 0.78 to 0.99]) and Kt/V (P = 0.054, OR = 0.03 [95% CI = 0.01 to 1.07]).
Depression is more prevalent than anxiety in HD patients. The risk of depression also increases with poorer dialysis adequacy and nutritional status. Thus, by improving dialysis adequacy and nutritional status, we can reduce the incidence of depression. However, a significant correlation cannot be drawn for anxiety.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 of the Square Kilometre Array (SKA1) and the science that they will enable. We highlight three main surveys: a medium-deep continuum weak lensing and low-redshift spectroscopic HI galaxy survey over 5 000 deg2; a wide and deep continuum galaxy and HI intensity mapping (IM) survey over 20 000 deg2 from
$z = 0.35$
to 3; and a deep, high-redshift HI IM survey over 100 deg2 from
$z = 3$
to 6. Taken together, these surveys will achieve an array of important scientific goals: measuring the equation of state of dark energy out to
$z \sim 3$
with percent-level precision measurements of the cosmic expansion rate; constraining possible deviations from General Relativity on cosmological scales by measuring the growth rate of structure through multiple independent methods; mapping the structure of the Universe on the largest accessible scales, thus constraining fundamental properties such as isotropy, homogeneity, and non-Gaussianity; and measuring the HI density and bias out to
$z = 6$
. These surveys will also provide highly complementary clustering and weak lensing measurements that have independent systematic uncertainties to those of optical and near-infrared (NIR) surveys like Euclid, LSST, and WFIRST leading to a multitude of synergies that can improve constraints significantly beyond what optical or radio surveys can achieve on their own. This document, the 2018 Red Book, provides reference technical specifications, cosmological parameter forecasts, and an overview of relevant systematic effects for the three key surveys and will be regularly updated by the Cosmology Science Working Group in the run up to start of operations and the Key Science Programme of SKA1.
Uranium–35 wt.% zirconium (U–35 wt.% Zr) alloy was annealed for 1 h and 24 h at 650 °C and characterized to understand the early-stage microstructure evolution. Dendritic microstructure with fine (∼300 nm in length) α-U precipitates clustered between dendrite branches were observed in the 1-h annealed sample. After 24-h annealing at 650 °C, the α-U precipitates coarsened, and the dendritic microstructure disappeared because of microstructure homogenization. Furthermore, microchemical homogenization observed with energy-dispersive X-ray spectroscopy analysis suggests that α-U precipitates are approaching thermodynamic equilibrium in the 24-h annealed sample. The findings from this study have potential impacts on the manufacturing and computer modeling of metallic nuclear fuel.
Attention-deficit/hyperactivity disorder (ADHD) is associated with a higher risk of burn injury than in the normal population. Nevertheless, the influence of methylphenidate (MPH) on the risk of burn injury remains unclear. This retrospective cohort study analysed the effect of MPH on the risk of burn injury in children with ADHD.
Data were from Taiwan's National Health Insurance Research Database (NHIRD). The sample comprised individuals younger than 18 years with a diagnosis of ADHD (n = 90 634) in Taiwan's NHIRD between January 1996 and December 2013. We examined the cumulative effect of MPH on burn injury risk using Cox proportional hazards models. We conducted a sensitivity analysis for immortal time bias using a time-dependent Cox model and within-patient comparisons using the self-controlled case series model.
Children with ADHD taking MPH had a reduced risk of burn injury, with a cumulative duration of treatment dose-related effect, compared with those not taking MPH. Compared with children with ADHD not taking MPH, the adjusted hazard ratio for burn injury was 0.70 in children taking MPH for <90 days (95% confidence interval (CI) 0.64–0.77) and 0.43 in children taking MPH for ≥90 days (95% CI 0.40–0.47), with a 50.8% preventable fraction. The negative association of MPH was replicated in age-stratified analysis using time-dependent Cox regression and self-controlled case series models.
This study showed that MPH treatment was associated with a lower risk of burn injury in a cumulative duration of treatment dose-related effect manner.
Re-planning mid-treatment, with the adjustment of target volumes, has been performed as part of the normal workflow at our institution. We sought to quantify the benefit of this approach and identify factors to optimise plan adaptive strategies.
Materials and methods:
Patients with locally advanced oropharyngeal cancer treated to 70 Gy with concurrent chemoradiation (CCRT) on TomoTherapy® who underwent re-planning during the treatment were eligible. Survival and prognostic factors were evaluated with Kaplan–Meier and Cox proportional hazards, two-side p-value <0·05 significant.
Forty-two patients were identified with Stage III (n = 5), IVA (n = 34) and IVB (n = 3) [AJCC 7th] disease. Median re-planning dose was 40 Gy (14–60 Gy). Median change in mean total parotid dose was reduction of 1 Gy (range –7·5 Gy to +13·9 Gy). The volume of PTV70 and PTV60 receiving 99% of the prescribed (V99) dose was increased by 2·2% (–3·3 to +16·6%) and 1·9% (–11·5 to +12·6%) by re-planning. As a continuous variable, increasing per cent nodal regression was associated with the improved disease control in a multivariate model including stage, pack years smoking and human papilloma viral (HPV) status (HR: 0·85, 0·71–0·99, p = 0·05).
Adaptive planning generates a superior plan for the majority of patients, but there is modest overall parotid gland sparing.
Thermal conductivity of uranium dioxide (UO2) is an important nuclear fuel performance property. Radiation- and fission-induced defects and microstructures, such as xenon (Xe) gas bubbles, can degrade the thermal conductivity of UO2 significantly. Here, molecular dynamics simulations are conducted to study the effect of Xe bubble size and pressure on the thermal conductivity of UO2. At a given porosity, thermal conductivity increases with Xe cluster size, then reaches a nearly saturated value at a cluster radius of 0.6 nm, demonstrating that dispersed Xe atoms result in a lower thermal conductivity than clustering them into bubbles. In comparison with empty voids of the same size, Xe-filled bubbles lead to a lower thermal conductivity when the number ratio of Xe atoms to uranium vacancies (Xe:VU ratio) in bubbles is high. Detailed atomic-level analysis shows that the pressure-induced distortion of atoms at bubble surface causes additional phonon scattering and thus further reduces the thermal conductivity.
Climatic change that affects biological productivity is often argued to be a primary force influencing human activities during the glacial period. To test this assumption, we combine in-site pollen, paleoclimatic, and archaeological data from the Dadiwan site and nearby areas on the western Loess Plateau (WLP) that date to Marine Oxygen Isotope Stage (MIS) 3. Our comparison of multiple datasets suggests that regional human activities increased when the vegetation around the Dadiwan area shifted from forest steppe in the early MIS 3 (59–46.7 ka) to steppe in the middle to late MIS 3 (46.7–29.5 ka). Our results indicate that regional human activities increased again during the late MIS 3 when the amount of precipitation was higher, as indicated by the lower Artemisia proportion. We suggest that increased precipitation on the WLP enhanced the above-ground biomass production and may be responsible for an increase in human activity and population in this region.
Environment can impact the wear behavior of metals and alloys substantially. The tribological properties of Al0.6CoCrFeNi high-entropy alloys (HEAs) were investigated in ambient air, deionized water, simulated acid rain, and simulated seawater conditions at frequencies of 2–5 Hz. The as-cast alloy was composed of simple face-centered cubic and body-centered cubic phases. The wear rate of the as-cast HEA in the ambient air condition was significantly higher than that in the liquid environment. The wear resistance in seawater was superior to that in ambient air, deionized water, and acid rain. Both the friction coefficient and wear rate in seawater were the lowest due to the formation of oxidation film, lubrication, and corrosion action in solution. The dominant wear mechanism in the ambient air condition and deionized water was abrasive wear, delamination wear, and oxidative wear. By contrast, the wear mechanism in acid rain and seawater was mainly corrosion wear, adhesive wear, abrasive wear, and oxidative wear.
Triticum monococcum ssp. monococcum has useful traits for bread wheat improvement. The synthesis of Triticum turgidum–T. monococcum amphiploids is an essential step for transferring genes from T. monococcum into bread wheat. In this study, 264 wide hybridization combinations were done by crossing 60 T. turgidum lines belonging to five subspecies with 83 T. monococcum accessions. Without embryo rescue and hormone treatment, from the 10,810 florets pollinated, 1983 seeds were obtained, with a mean crossability of 18.34% (range 0–89.29%). Many hybrid seeds (90.73%, 923/1017) could germinate and produce plants. A total of 56 new amphiploids (AABBAmAm) were produced by colchicine treatment of T. turgidum × T. monococcum F1 hybrids. The chromosome constitution of amphiploids was characterized by fluorescence in situ hybridization using oligonucleotides probes with different chromosome and sub-chromosome specificities. Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis indicated that the Glu-A1m-b, Glu-A1m-c, Glu-A1m-d and Glu-A1m-h proteins of T. monococcum were expressed in some amphiploids. Despite resistance reduction in several cases, 45 out of 56 amphiploids exhibited resistance to the current predominant Chinese stripe rust races at both the seedling and adult plant stage. These novel amphiploids provide new germplasm for the potential improvement of bread wheat quality and stripe rust resistance.