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We describe the case of a newborn infant with transposition of the great vessels and a retroaortic innominate vein. This is a previously undescribed association. The decision was made to incorporate the retroaortic innominate vein into the Lecompte procedure at the time of surgery to avoid the risk of superior caval vein syndrome.
To date, Ireland has been a leading light in the provision of youth mental health services. However, cognisant of the efforts of governmental and non-governmental agencies working in youth mental health, there is much to be done. Barriers into care as well as discontinuity of care across the spectrum of services remain key challenges. This editorial provides guidance for the next stage of development in youth mental care and support that will require significant national engagement and resource investment.
The unique phenotypic and genetic aspects of obsessive-compulsive (OCD) and attention-deficit/hyperactivity disorder (ADHD) among individuals with Tourette syndrome (TS) are not well characterized. Here, we examine symptom patterns and heritability of OCD and ADHD in TS families.
OCD and ADHD symptom patterns were examined in TS patients and their family members (N = 3494) using exploratory factor analyses (EFA) for OCD and ADHD symptoms separately, followed by latent class analyses (LCA) of the resulting OCD and ADHD factor sum scores jointly; heritability and clinical relevance of the resulting factors and classes were assessed.
EFA yielded a 2-factor model for ADHD and an 8-factor model for OCD. Both ADHD factors (inattentive and hyperactive/impulsive symptoms) were genetically related to TS, ADHD, and OCD. The doubts, contamination, need for sameness, and superstitions factors were genetically related to OCD, but not ADHD or TS; symmetry/exactness and fear-of-harm were associated with TS and OCD while hoarding was associated with ADHD and OCD. In contrast, aggressive urges were genetically associated with TS, OCD, and ADHD. LCA revealed a three-class solution: few OCD/ADHD symptoms (LC1), OCD & ADHD symptoms (LC2), and symmetry/exactness, hoarding, and ADHD symptoms (LC3). LC2 had the highest psychiatric comorbidity rates (⩾50% for all disorders).
Symmetry/exactness, aggressive urges, fear-of-harm, and hoarding show complex genetic relationships with TS, OCD, and ADHD, and, rather than being specific subtypes of OCD, transcend traditional diagnostic boundaries, perhaps representing an underlying vulnerability (e.g. failure of top-down cognitive control) common to all three disorders.
Aberrant emotional biases have been reported in bipolar disorder (BD), but results are inconsistent. Despite the clinical relevance of chronic mood variability in BD, there is no previous research investigating how the extent of symptom fluctuations in bipolar disorder might relate to emotional biases. This exploratory study investigated, in a large cohort of bipolar patients, whether instability in weekly mood episode symptoms and other clinical and demographic factors were related to emotional bias as measured in a simple laboratory task.
Participants (N = 271, BDI = 206, BDII = 121) completed an ‘emotional categorization and memory’ task. Weekly self-reported symptoms of depression and mania were collected prospectively. In linear regression analyses, associations between cognitive bias and mood variability were explored together with the influence of demographic and clinical factors, including current medication.
Greater accuracy in the classification of negative words relative to positive words was associated with greater instability in depressive symptoms. Furthermore, greater negative bias in free recall was associated with higher instability in manic symptoms. Participants diagnosed with BDII, compared with BDI, showed overall better word recognition and recall. Current antipsychotic use was associated with reduced instability in manic symptoms but this did not impact on emotional processing performance.
Emotional processing biases in bipolar disorder are related to instability in mood. These findings prompt further investigation into the underpinnings as well as clinical significance of mood instability.
I describe a project to survey ∼ 13 square degrees of the sky at 15μm and 90μm with the Infrared Space Observatory (ISO). The European Large Area ISO Survey (ELAIS) is a collaboration involving 19 European institutes (in addition to the authors and others at their institutes the following people and others their institutes are involved I. Gonzalez-Serrano, E. Kontizas, K. Mandolesi, J. Masegosa, K. Mattila, H. Norgaard-Nielsen, I. Perez-Fournon, M. Ward) and is the largest open time project being undertaken by ISO. We expect to detect at least 1000 extra-galactic objects and a similar number of Galactic sources.
We have conducted a survey of the Lyα forest in the redshift domain 2.15 < z < 3.37 in front of nine QSOs within a 1o field to probe spatial structure along planes perpendicular to the line-of-sight. We find evidence for correlations of the Lyα absorption line wavelengths in the whole redshift range, and, at z > 2.8, of their equivalent widths. Such a correlation is consistent with the emerging picture that Lyα lines arise in filaments or large, flattened structures.
The multi-object spectroscopic facility FOCAP at the Anglo-Australian Telescope has been used to obtain spectra centred at the Ca II IR triplet of 14 stars in the field of the Sextans dwarf spheroidal (dSph) galaxy. This satellite of our own Galaxy was recently discovered by Irwin et al. (1990) from APM measures of UK Schmidt Telescope photographic plates.
The first QSO with a redshift z > 4 was found using a combination of UK Schmidt Telescope (UKST) plates and the APM automatic plate measuring machine (Warren et al. 1987a). By continuing to make use of UKST survey plates plus the APM facility we have added substantially to the number of known QSOs with z > 4. A brief description of the general survey technique is presented together with a preliminary discussion of some of the results obtained so far.
Among the most interesting objects found on low dispersion IllaJ objective prism plates taken with the UK Schmidt telescope are a large number of compact and intrinsically very bright ‘extragalactic HII regions’. Spectroscopically they are indistinguishable from the giant HII regions found in spiral and irregular galaxies except that they are much more luminous with absolute magnitudes in the range My -14 to -23. The stellar continuum is extremely blue indicating a predominantly young stellar population. The Hf3 luminosities, 1038 to 1042 ergs/sec indicate that they must contain 105 - 107 OB stars with a total mass in stars of 106 - 109 Mʘ. The associated high rate of star formation cannot have continued for more than 107 years, which implies that these systems are either undergoing star formation for the first time, or that they undergo intermittent bursts of star formation. The chemical composition of these systems is also remarkable in that the oxygen abundance is invariably less than solar.
Twin and family studies using Western samples have established that child and adolescent anxiety and depression are under substantial genetic, modest shared environmental, and substantial non-shared environmental influences. Generalizability of these findings to non-Western societies remains largely unknown, particularly regarding the changes of genetic and environmental influences with age. The current study examined changes in genetic and environmental influences on self-reported anxiety and depression from late childhood to mid-adolescence among a Chinese twin sample. Sex differences were also examined.
Self-reported anxiety and depression were collected from 712 10- to 12-year-old Chinese twins (mean = 10.88 years, 49% males) and again 3 years later. Quantitative genetic modeling was used to examine developmental changes in genetic and environmental influences on anxiety and depression, and sex differences.
Heritability of anxiety and depression in late childhood (23 and 20%) decreased to negligible in mid-adolescence, while shared environmental influences increased (20 and 27% to 57 and 60%). Shared environmental factors explained most of the continuity of anxiety and depression (75 and 77%). Non-shared environmental factors were largely time-specific. No sex differences were observed.
Shared environmental influences might be more pronounced during the transition period of adolescence in non-Western societies such as China. Future research should examine similarities and differences in the genetic and environmental etiologies of child and adolescent internalizing and other psychopathology in development between Western and non-Western societies.
Surveys with ISO (Kessler et al 1996), in particular with the CAM (Cesarsky et al 1996) and PHOT (Lemke et al 1996) instruments, will greatly extend our understanding of extra-galactic populations and their cosmological evolution. The main advantages that ISO surveys have over e.g IRAS are increased sensitivity/depth and wavelength coverage. Within the Guaranteed and Open Time programmes there are many field surveys which will efficiently map the limits in these parameters. In this talk I will briefly overview those surveys before concentrating in more detail on one survey in particular, the ISO survey of the Hubble Deep Field (HDF), to illustrate the kind of results that can be expected.
The aim of this work was to determine if volumetric modulated arc therapy (VMAT) plans, created for constant dose-rate (cdrVMAT) delivery are a viable alternative to step and shoot five-field intensity modulated radiation therapy (IMRT).
Materials and methods
The cdrVMAT plans, inverse planned on a treatment planning system with no solution to account for couch top or rails, were created for delivery on a linear accelerator with no variable dose rate control system. A series of five-field IMRT and cdrVMAT plans were created using dual partial arcs (gantry rotating between 260° and 100°) with 4° control points for ten prostate patients with the average rectal constraint incrementally increased. Pareto fronts were compared for the planning target volume homogeneity and average rectal dose between the two techniques for each patient. Also investigated were tumour control probability and normal tissue complication probability values for each technique. The delivery parameters [monitor units (MU) and time] and delivery accuracy of the IMRT and VMAT plans were also compared.
Pareto fronts showed that the dual partial arc plans were superior to the five-field IMRT plans, particularly for the clinically acceptable plans where average rectal doses were less for rotational plans (p = 0·009) with no statistical difference in target homogeneity. The cdrVMAT plans had significantly more MU (p = 0·005) but the average delivery time was significantly less than the IMRT plans by 42%. All clinically acceptable cdrVMAT plans were accurate in their delivery (gamma 99·2 ± 1·1%, 3%3 mm criteria).
Accurate delivery of dual partial arc cdrVMAT avoiding the couch top and rails has been demonstrated.
The critical adhesion energy of benzocyclobutene (BCB)-bonded wafers is
quantitatively investigated with focus on BCB thickness, material stack and
thermal cycling. The critical adhesion energy depends linearly on BCB
thickness, increasing from 19 J/m2 to 31 J/m2 as the
BCB thickness increases from 0.4 μm to 2.6 μm, when bonding silicon wafers
coated with plasma enhanced chemical vapor deposited (PECVD) silicon dioxide
(SiO2). In thermal cycling performed with 350 and 400 oC peak temperatures,
the significant increase in critical adhesion energy at the interface
between BCB and PECVD SiO2 during the first thermal cycle is
attributed to relaxation of residual stress in the PECVD SiO2
layer. On the other hand, the critical adhesion energy at the interface
between BCB and PECVD silicon nitride (SiNx) decreases due to the
increase of residual stress in the PECVD SiNx layer during the
first thermal cycle.
The formation of silicon-on-insulator structures, by recrystallising polycrystalline silicon films with a dual electron beam technique, has been studied over a wide range of conditions. The quality of the layers has been assessed by examining cross-sections in the SEM and optical microscopy of the surface after a Secco etch. The range of line powers which gives device-worthy single crystal material becomes greater as the sweep speed increases and as the background temperature is reduced. The extent of melting into the substrate in the seed windows and below the isolating oxide was determined from the movement of an arsenic implant. The experimental results are compared to the predictions from a one dimensional model for the heat flow.
The diffusion and activation of implanted boron in silicon during rapid thermal annealing (RTA) has been studied using the analytical techniques of SIMS, TEM, and sheet resistance measurements. Both crystalline and pre-amorphised silicon substrates were investigated. Data analysis in conjunction with a range of numerical models indicates some novel features of boron RTA, as well as accounting for previously observed features. In particular, a large transient diffusion enhancement coupled with an increase of electrical activity, are seen at short anneal times, in the case of crystalline silicon substrates. A non-equilibrium diffusion enhancement of a different type is also seen at much longer times, in both crystalline and pre-amorphised samples implanted to high doses. This second enhancement persists after all the precipitated boron formed on implantation has become substitutional. TEM studies show that the transient enhancement may be associated with the evolution of extended defect structures during the early stages of annealing. Both types of enhancement can be well represented by multiplying the ‘normal’ concentration-dependent diffusivity (with β=0.5) by a factor f>1.
A dual electron beam machine has been used to anneal boron implanted layers in order to study the diffusion and activation behaviour over a wide range of doses. The annealed implants have been characterized by spreading resistance profiling and secondary ion mass spectroscopy (SIMS). Carrier concentration profiles show that millisecond duration anneals can activate boron implants. A boron dose of 1E16 ions/cm2 was annealed to give a sheet resistance of 30 Ωsq with 40% of the implant activated. The SIMS technique showed there were no significant differences between the atomic profiles of the as-implanted samples and specimens subjected to a millisecond anneal or to a low temperature 850°C rapid isothermal anneal for 10s.