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.
While echocardiographic parameters are used to quantify ventricular function in infants with single ventricle physiology, there are few data comparing these to invasive measurements. This study correlates echocardiographic measures of diastolic function with ventricular end-diastolic pressure in infants with single ventricle physiology prior to superior cavopulmonary anastomosis.
Data from 173 patients enrolled in the Pediatric Heart Network Infant Single Ventricle enalapril trial were analysed. Those with mixed ventricular types (n = 17) and one outlier (end-diastolic pressure = 32 mmHg) were excluded from the analysis, leaving a total sample size of 155 patients. Echocardiographic measurements were correlated to end-diastolic pressure using Spearman’s test.
Median age at echocardiogram was 4.6 (range 2.5–7.4) months. Median ventricular end-diastolic pressure was 7 (range 3–19) mmHg. Median time difference between the echocardiogram and catheterisation was 0 days (range −35 to 59 days). Examining the entire cohort of 155 patients, no echocardiographic diastolic function variable correlated with ventricular end-diastolic pressure. When the analysis was limited to the 86 patients who had similar sedation for both studies, the systolic:diastolic duration ratio had a significant but weak negative correlation with end-diastolic pressure (r = −0.3, p = 0.004). The remaining echocardiographic variables did not correlate with ventricular end-diastolic pressure.
In this cohort of infants with single ventricle physiology prior to superior cavopulmonary anastomosis, most conventional echocardiographic measures of diastolic function did not correlate with ventricular end-diastolic pressure at cardiac catheterisation. These limitations should be factored into the interpretation of quantitative echo data in this patient population.
In this systematic evaluation of fluorescent gel markers (FGM) applied to high-touch surfaces with a metered applicator (MA) made for the purpose versus a generic cotton swab (CS), removal rates were 60.5% (476 of 787) for the MA and 64.3% (506 of 787) for the CS. MA-FGM removal interpretation was more consistent, 83% versus 50% not removed, possibly due to less varied application and more adhesive gel.
Objectives: Rates of cognitive, academic and behavioral comorbidities are elevated in children with epilepsy. The contribution of environmental and genetic influences to comorbidity risk is not fully understood. This study investigated children with epilepsy, their unaffected siblings, and controls to determine the presence and extent of risk associated with family relatedness across a range of epilepsy comorbidities. Methods: Participants were 346 children (8–18 years), n=180 with recent-onset epilepsy, their unaffected siblings (n=67), and healthy first-degree cousin controls (n=99). Assessments included: (1) Child Behavior Checklist/6-18 (CBCL), (2) Behavior Rating Inventory of Executive Function (BRIEF), (3) history of education and academic services, and (4) lifetime attention deficit hyperactivity disorder (ADHD) diagnosis. Analyses consisted of linear mixed effect models for continuous variables, and logistic mixed models for binary variables. Results: Differences were detected between the three groups of children across all measures (p<.001). For ADHD, academic problems, and executive dysfunction, children with epilepsy exhibited significantly more problems than unaffected siblings and controls; siblings and controls did not differ statistically significantly from each other. For social competence, children with epilepsy and their unaffected siblings displayed more abnormality compared with controls, with no statistically significant difference between children with epilepsy and unaffected siblings. For behavioral problems, children with epilepsy had more abnormality than siblings and controls, but unaffected siblings also exhibited more abnormalities than controls. Conclusions: The contribution of epilepsy and family relatedness varies across specific neurobehavioral comorbidities. Family relatedness was not significantly associated with rates of ADHD, academic problems and executive dysfunction, but was associated with competence and behavioral problems. (JINS, 2018, 24, 1–9)
There has recently been an increased interest in mental health indicators for the monitoring of population wellbeing, which is among the targets of Sustainable Development Goals adopted by the United Nations. Levels of subjective wellbeing and suicide rates have been proposed as indicators of population mental health, but prior research is limited.
Data on individual happiness and life satisfaction were sourced from a population-based survey in Hong Kong (2011). Suicide data were extracted from Coroner's Court files (2005–2013). Area characteristic variables included local poverty rate and four factors derived from a factor analysis of 21 variables extracted from the 2011 census. The associations between mean happiness and life satisfaction scores and suicide rates were assessed using Pearson correlation coefficient at two area levels: 18 districts and 30 quantiles of large street blocks (LSBs; n = 1620). LSB is a small area unit with a higher level of within-unit homogeneity compared with districts. Partial correlations were used to control for area characteristics.
Happiness and life satisfaction demonstrated weak inverse associations with suicide rate at the district level (r = −0.32 and −0.36, respectively) but very strong associations at the LSB quantile level (r = −0.83 and −0.84, respectively). There were generally very weak or weak negative correlations across sex/age groups at the district level but generally moderate to strong correlations at the LSB quantile level. The associations were markedly attenuated or became null after controlling for area characteristics.
Subjective wellbeing is strongly associated with suicide at a small area level; socioeconomic factors can largely explain this association. Socioeconomic factors could play an important role in determining the wellbeing of the population, and this could inform policies aimed at enhancing population wellbeing.
We here report the results of a systematic investigation of how binary interaction affects the presupernova evolution of massive stars and the resulting supernova explosions. We summarize the various types of binary interaction and the evolutionary scenarios in which they are realized. We also present the results of a series of hydrodynamical calculations which model the supernova explosion for various progenitor types and discuss their observable characteristics.
Despite published catheter-associated urinary tract infection prevention guidelines, inappropriate catheter use is common. We surveyed housestaff about their knowledge of catheter-associated urinary tract infections at a teaching hospital and found most are aware of prevention guidelines; however, their application to clinical scenarios and catheter practices fall short of national goals.
Infect. Control Hosp. Epidemiol. 2015;36(11):1355–1357
We describe a laboratory plasma physics experiment at Los Alamos National Laboratory that uses two merging supersonic plasma jets formed and launched by pulsed-power-driven railguns. The jets can be formed using any atomic species or mixture available in a compressed-gas bottle and have the following nominal initial parameters at the railgun nozzle exit: ne ≈ ni ~ 1016 cm−3, Te ≈ Ti ≈ 1.4 eV, Vjet ≈ 30–100 km/s, mean charge
≈ 1, sonic Mach number Ms ≡ Vjet/Cs > 10, jet diameter = 5 cm, and jet length ≈20 cm. Experiments to date have focused on the study of merging-jet dynamics and the shocks that form as a result of the interaction, in both collisional and collisionless regimes with respect to the inter-jet classical ion mean free path, and with and without an applied magnetic field. However, many other studies are also possible, as discussed in this paper.
To investigate and compare the performance of head mirrors and headlights during otolaryngological examination.
The illuminance and illumination field of each device were measured and compared. Visual identification and visual acuity were also measured, in 13 medical students and 10 otolaryngology specialists.
The illuminance (mean ± standard deviation) of the LumiView, Kimscope 1 W and Kimscope 3 W headlights and a standard head mirror were 352.3 ± 9, 92.3 ± 4.5, 438 ± 15.7 and 68.3 ± 1.2 lux, respectively. The illumination field of the head mirror (mean ± standard deviation) was 348 ± 29.8 grids, significantly greater than that of the Kimscope 3 W headlight (183 ± 9.2 grids) (p = 0.0017). The student group showed no statistically significant difference between visual identification with the best headlight and the head mirror (score means ± standard deviations: 56.2 ± 9 and 53.3 ± 14.1, respectively; p = 0.3). The expert group scored significantly higher for visual identification with head mirrors versus headlights (59.7 ± 3.3 vs 55.2 ± 5.8, respectively; p = 0.0035), but showed no difference for visual acuity.
Despite the advantages of headlight illumination, head mirrors provided better, shadow-free illumination. Despite no differences amongst students, head mirrors performed better than headlights in experienced hands.
The hydrogenated amorphous silicon (a-Si:H) single-junction thin-film solar cells were fabricated on SnO2:F-coated glasses by plasma-enhanced chemical vapor deposition (PECVD) system. The boron-doped amorphous silicon carbide (a-SiC:H) was served as the window layer (p-layer) and the undoped a-SiC:H was used as a buffer layer (b-layer). The optimization of the p/b/i/n thin-films in a-Si:H solar cells have been carried out and discussed. Considering the effects of light absorption, electron-hole extraction and light-induced degradation, the thicknesses of p, b, n and i layers have been optimized. The optimal a-Si:H thin-film solar cell having an efficiency of 9.46% was achieved, with VOC=906 mV, JSC=14.42 mA/cm2 and FF=72.36%.
There is a growing interest in the application of large area electronics on curved surfaces. One approach towards realizing this goal is to fabricate circuits on planar substrates of thin plastic or metal foil, which are subsequently deformed into arbitrary shapes. The problem that we consider here is the deformation of substrates into a spherical shape, where the strain is determined by geometry and cannot be reduced by simply using a thinner substrate. The goal is to achieve permanent, plastic deformation in the substrates, without exceeding fracture or buckling limits in the device materials.
Our experiments consist of the planar fabrication of amorphous silicon device structures onto stainless steel or Kapton® polyimide substrates, followed by permanent deformation into a spherical shape. We will present empirical experiments showing the dependence of the results on the island/line size of the device materials and the deformation temperature. We have successfully deformed Kapton® polyimide substrates with 100 [.proportional]m wide amorphous silicon islands into a one steradian spherical cap, which subtends 66 degrees, without degradation of the silicon. This work demonstrates the feasibility of building semiconductor devices on plastically deformed substrates despite a 5% average biaxial strain in the substrate after deformation.
The beam position monitors (BPMs) with submicron-level resolution act as the major eyes of storage ring in detecting the position of electron beams and are used for feedback system to guide the beam orbit to the desired track. Compared to major improvements on backend electronics, the physical devices generate and transmit signals had little improvement due to the lack of control on manufacturing processes including all mechanical tolerance requirements. The design started with ANSYS to simulate mechanical deformation. Due to the small size (submillimetre) and complicated assembly of feedthrough structure, it is difficult to achieve 1 % tolerance (submicron) in all aspects including machining and brazing. The smallest tolerance for machining is 5 µ and the overall tolerance will be 30 µm. The influence of the tolerance on mechanical will be shown on time-domain reflectometry measurement. The resulted heat-related issue will also be discussed and addressed since the problem happened at SLAC (private communication with Albert Sheng at Stanford Linear Accelerator Center) and DIAMOND (presented at the RF Button Heating Mini-Workshop at EPAC 2008). Manufacturing steps will be described. The consequence of mismatch on manufacturing will be discussed. All related measurement and simulation data are presented in this paper.
We utilized the conventional planar fabrication technique and the electrochemical etching method to prepare porous Si layers in the p-type region of a p/n junction, which could make the study on the transverse transport property of this material possible. The junctions were fabricated by low energy ion-implantation, with porous Si formed perpendicular to the junction and between two metal contacts. This structure confines currents to the direction parallel to the surface. Distinct features on current-voltage (I-V) curves has been observed.
High‐T YBaCuO and BiSrCaCuO Superconducting wires have been fabricated by powder metallurgy technique. Copper and silver tubes were used as the external jackets. Thermal annealing treatments for all the wire‐type samples were performed between 773 K and 1223 K. Both electrical and magnetization studies show that the superconducting properties can be improved after properly thermal annealing these samples with silver jacket. Our experimental results show that proper thermal annealing treatment can enhance the intragrain critical current density more than 100 times; however, the intergrain critical current density improves only a few times.
The superconductivity of pseudo-quternary system Y1−xMx Ba2 Cu3 O7-δ, YBa2 Cu3−xM x O7-δ, where M stands Co,Cr,&Zn and with x=0,0.001,0.005,0.01 & 0.02, has been investigated.
The XRD analysis shows that the perovskite structure is preserved and a stabilization effect on orthorhombic structure by 3d elements addition was proposed. On the contrary, the microstructure has been modified prominently and it is determined by the sintering mechanism involved and/or diffusion process in each doped sample. Second phase precipitate can be found at grain surface. The superconductivity, however, has not been greatly affected.
In this paper we will describe the production, separation and characterization of the new all carbon molecules, C60 and C70. High performance liquid chromatography HPLC is used to obtain purified samples of C60 and C70, which are subsequently characterized by electron impact and chemical ionization mass spectrometry, IR and UV-visible absorption spectroscopy, NMR, ESR, scanning tunnelling microscopy, transmission electron microscopy and x-ray absorption fine structure measurements.
A new melt-spinning technique (field quenching) for ferromagnetic amorphous ribbon is suggested to produce better magnetic properties than conventional as-quenched amorphous ribbon. An external field is applied during the quenching either parallel or perpendicular to the casting direction. The magnetic moment and initial permeability are increased when the field direction is parallel to the casting direction. These effects are opposite when these two directions mentioned are perpendicular to each other.