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We compared antibiotic prescribing to older people in different settings to inform antibiotic stewardship interventions. We used data linkage to stratify individuals aged 65 years and over in Northern Ireland, 1st January 2012–31st December 2013, by residence: community dwelling, care home dwelling or ‘transitioned’ if admitted to a care home. The odds of being prescribed an antibiotic by residence were analysed using logistic regression, adjusting for patient demographics and selected medication use (proxy for co-morbidities). Trends in monthly antibiotic prescribing were examined in the 6 months pre- and post-admission to the care home. The odds of being prescribed at least one antibiotic were twofold higher in care homes compared with community dwellers (adjusted odds ratio 2.05, 95% CI 1.93–2.17). There was a proportionate increase of 51.5% in the percentage prescribed an antibiotic on admission, with a monthly average of 23% receiving an antibiotic in the 6 months post admission. While clinical need likely accounts for some of the observed antibiotic prescribing in care homes we cannot rule out more liberal prescribing, given the twofold difference between care home residents and their community dwelling peers having accounted for co-morbidities. The appropriateness of antibiotic prescribing in the care home setting should be examined.
Given the challenges in accurately identifying unexposed controls in case–control studies of diarrhoea, we examined diarrhoea incidence, subclinical enteric infections and growth stunting within a reference population in the Global Enteric Multicenter Study, Kenya site. Within ‘control’ children (0–59 months old without diarrhoea in the 7 days before enrolment, n = 2384), we examined surveys at enrolment and 60-day follow-up, stool at enrolment and a 14-day post-enrolment memory aid for diarrhoea incidence. At enrolment, 19% of controls had ⩾1 enteric pathogen associated with moderate-to-severe diarrhoea (‘MSD pathogens’) in stool; following enrolment, many reported diarrhoea (27% in 7 days, 39% in 14 days). Controls with and without reported diarrhoea had similar carriage of MSD pathogens at enrolment; however, controls reporting diarrhoea were more likely to report visiting a health facility for diarrhoea (27% vs. 7%) or fever (23% vs. 16%) at follow-up than controls without diarrhoea. Odds of stunting differed by both MSD and ‘any’ (including non-MSD pathogens) enteric pathogen carriage, but not diarrhoea, suggesting control classification may warrant modification when assessing long-term outcomes. High diarrhoea incidence following enrolment and prevalent carriage of enteric pathogens have implications for sequelae associated with subclinical enteric infections and for design and interpretation of case–control studies examining diarrhoea.
The effects of shape and thickness of a tin surface layer and of the energy of a 170 ps neodymium:yttrium-aluminum-garnet laser pulse on the conversion efficiency (CE) into extreme ultraviolet emission in the 13.5 nm region is investigated. Whereas a CE of up to 1.16% into the 2% reflection band of multilayer Mo/Si optics was measured for a bulk Sn target at a laser energy of 25 mJ, significant CE enhancement up to 1.49% is demonstrated for a 200-nm-thick Sn layer on a microstructured porous alumina substrate.
Untreated maternal depression during the postpartum period can have a profound impact on the short- and long-term psychological and physical well-being of children. There is, therefore, an imperative for increased understanding of the determinants of depression and depression-related healthcare access during this period.
Respondents were 11 089 mothers of 9-month-old infants recruited to the Growing Up in Ireland study. Of this sample, 10 827 had complete data on all relevant variables. Respondents provided sociodemographic, socioeconomic and household information, and completed the Center for Epidemiologic Studies Depression Scale (CESD).
11.1% of mothers scored above the CESD threshold for depression. 10.0% of depressed mothers and 25.4% of depressed fathers had depressed partners. Among depressed mothers, 73.1% had not attended a healthcare professional for a mental health problem since the birth of the cohort infant. In the adjusted model, the likelihood of depression was highest in mothers who: had lower educational levels (odds ratio (OR) 1.26; 95% confidence intervals (CIs) 1.08, 1.46); were unemployed (OR 1.27; 95% CIs 1.10, 1.47); reported previous mental health problems (OR 6.55; 95% CIs 5.68, 7.56); reported that the cohort child was the result of an unintended pregnancy (OR 1.43; 95% CIs 1.22, 1.68), was preterm (OR 1.35; 95% CIs 1.07, 1.70), or had health/developmental problems (OR 1.20; 95% CIs 1.04, 1.39); had no partner in the household (OR 1.33; 95% CIs 1.04, 1.70) or were living with a depressed partner (OR 2.66; 95% CIs 1.97, 3.60); reported no family living nearby (OR 1.33; 95% CIs 1.16, 1.54); were in the lowest income group (OR 1.60; 95% CIs 1.21, 2.12). The primary determinant of not seeking treatment for depression was being of non-white ethnicity (OR 2.21; 95% CIs 1.18, 4.13).
Results highlight the prevalence of maternal depression in the later postpartum period, particularly for lower socioeconomic groups, those with previous mental health problems, and those with limited social support. The large proportion of unmet need in depressed mothers, particularly among ethnic minority groups, emphasises the need for a greater awareness of postpartum mental health problems and increased efforts by healthcare professionals to ensure that mothers can access the required services.
Many medications administered to patients with schizophrenia possess anticholinergic properties. When aggregated, pharmacological treatments may result in a considerable anticholinergic burden. The extent to which anticholinergic burden has a deleterious effect on cognition and impairs ability to participate in and benefit from psychosocial treatments is unknown.
Seventy patients were followed for approximately 3 years. The MATRICS consensus cognitive battery (MCCB) was administered at baseline. Anticholinergic burden was measured with the Anticholinergic Cognitive Burden (ACB) scale. Ability to benefit from psychosocial programmes was measured using the DUNDRUM-3 Programme Completion Scale (D-3) at baseline and follow-up. Psychiatric symptoms were measured using the PANSS. Total antipsychotic dose was measured using chlorpromazine equivalents. Functioning was measured using the Social and Occupational Functioning Assessment Scale (SOFAS).
Mediation analysis found that the influence of anticholinergic burden on ability to participate and benefit from psychosocial programmes was completely mediated by the MCCB. For every 1-unit increase on the ACB scale, change scores for DUNDRUM-3 decreased by −0.27 points. This relationship appears specific to anticholinergic burden and not total antipsychotic dose. Moreover, mediation appears to be specific to cognition and not psychopathology. Baseline functioning also acted as mediator but only when MCCB was not controlled for.
Anticholinergic burden has a significant impact on patients’ ability to participate in and benefit from psychosocial treatment programmes. Physicians need to be mindful of the cumulative effect that medications can have on patient cognition, functional capacity and ability to benefit from psychosocial treatments.
The aim of the current study was to gain insight into the process of initiation and progression to problematic use among young people who reach clinically significant levels of substance use requiring treatment.
Twenty young people, aged between 15 and 19 years from two different drug treatment centres in Ireland were interviewed regarding their views on their pathway into substance use, their progress to more problematic use, their perception of their parents’ role, if any, in their trajectory and their typical coping style before treatment. Content analysis was conducted on the resulting narratives.
The use of substances to cope with life stressors emerged as a prominent theme at initial and problematic stages of use. Multiple maladaptive coping approaches were reported. Both direct and indirect influences from parents in their substance use problem were cited. However, some participants reported that parents had no causal role in their substance use trajectory, in particular regarding mothers.
The current findings suggest that substance misuse is a multi-determined problem and a number of intervention strategies are suggested to delay onset and related harms associated with adolescent substance use.
We present a theoretical analysis of the electronic structure of GaN quantum dots (QD) with an adjacent threading dislocation. The QD carrier spectra and wavefunctions are calculated using a plane-wave expansion method within an 8-band k.p model. The method is very efficient, because the strain and built-in electric fields can be included through their discrete Fourier transforms. The QD structures considered have been analysed experimentally by other groups. The GaN QDs are truncated hexagonal pyramids on a wetting layer with an edge dislocation adjacent to each dot. The built-in piezoelectric potential strongly influences the localisation of the carrier wavefunctions. This potential pushes the electrons to the top of the dot, the holes to the bottom and, additionally, causes strong lateral confinement of the carriers. The effect of the dislocation strain field at the dot edge on the carrier states in each GaN/AlN QD is shown to be insignificant. Results are presented for the confined state energies and optical matrix elements for a range of different sized dots with and without dislocations. The size of the dot influences the energies and overlaps, but the presence of the dislocation has minimal effect. The dependence of the ground state optical transition energy on the size of the dot is in good agreement with experimental data.
Polycrystalline samples of YBa2Cu2O7-δ with a variety of surface treatments show differences in absolute reflectance and width of phonon lines. Samples that are not polished and are measured immediately after annealing have largely grains with the c axis normal to the surface. Such oriented samples show a gap-like depression of conductivity in the far infrared that sets in below the superconducting transition temperature but no true gap. Phonon lines at 195 cm−1 and at 155 cm−1 narrow in the superconducting state, in analogy with the effect of the electron phonon interaction in BCS superconductors. In the normal state the background conductivity is Drude like with a plasma frequency of 0.75 eV and a relaxation rate of 200 cm−1. The extrapolated far-infrared conductivity agrees with the measured dc conductivity.
Optical reflectance spectra in the range 30–35000 cm-1 and 4–300 K are presented on several YBa2CuxOy phases, as well as different forms of the superconducting YBa2CuxO7−x (polycrystalline pellets, textured pellets with ab-plane oriented surface, and single crystals).
Variations in maternal nutrition during gestation can influence foetal growth, foetal development and permanently ‘programme’ offspring for postnatal life. The objective of this study was to analyse the effect of increased maternal nutrition during different gestation time windows on offspring growth, carcass quality, meat quality and gene expression in skeletal muscle. A total of 64 sows were assigned to the following feeding treatments: a standard control diet at a feed allocation of 2.3 kg/day throughout gestation, increased feed allowance of 4.6 kg/day from 25 to 50 days of gestation (dg), from 50 to 80 dg and from 25 to 80 dg. At weaning, Light, Medium and Heavy pigs of the same gender, within litter, were selected based on birth weight, individually penned and monitored until slaughter at 130 days post weaning. Carcass and meat quality traits of the semimembranosus (SM) muscle were recorded post mortem. A cross section of the semitendinosus (ST) muscle encompassing the deep and superficial regions were harvested from pigs (n = 18 per treatment) for RNA extraction and quantification of gene expression by real-time PCR. The results showed that doubling the feed intake from 25 to 50 dg reduced offspring growth, carcass weight, intramuscular fat content and increased drip loss of the SM muscle. Interestingly, protein phosphatase 3 catalytic subunit – α-isoform, which codes for the transcription factor calcineurin, was upregulated in the ST muscle of offspring whose mothers received increased feed allowance from 25 to 50 dg. This may provide an explanation for the previous observed increases in Type IIa muscle fibres of these offspring. Increasing the maternal feed intake from 50 to 80 dg negatively impacted pig growth and carcass weight, but produced leaner male pigs. Extending the increased maternal feed intake from 25 to 80 dg had no effect on offspring over the standard control gestation diet. Although intra-litter variation in pig weight is a problem for pig producers, increased maternal feeding offered no improvement throughout life to the lighter birth weight littermates in our study. Indeed, increased maternal nutrition at the three-gestation time windows selected provided no major benefits to the offspring.
Molecular dynamics simulation has been performed with dense systems of alkane-like chain molecules. Distribution of occupied and unoccupied space in the system was then evaluated by the technique of Voronoi tessellation of space and by enumeration of the cavities formed when hard spheres of diameter D were assumed placed on atomic centers. The distribution of cavity volumes is extremely broad and often exhibits a bimodal or trimodal character. These cavities change shape and size with time even at temperatures much below Tg.
An optically homogeneous sample of highly syndiotactic poly(n-butyl methacrylate) (PBMA) has been prepared. The glass transition temperature was observed to be Tg=55C. Measurements of the scattered intensity of the sample followed the expected behavior for a pure liquid above Tg. The intensity rose as the sample was cooled further towards the glass transition temperature for atactic PBMA. These results illuminate the importance of regions of different stereoisomers in methacrylate polymers. Measurements of the Rayleigh- Brillouin spectrum were carried out from -15 to 130 C. The ratio of the the central peak intensity to the Brillouin intensities at temperatures above Tg was consistent with a viscoelastic liquid and had a magnitude near 3. The Brillouin linewidth remained large near Tg. and decreased continuosly with no apparent change in slope in the glass transition region. The presence and importance of rapid motions in polymers near the glass transistion is demonstrated by these results. Slowly relaxing density fluctuations near Tg. were measured by photon correlation spectroscopy. Relaxation functions were obtained from 10−6 to 10 s. Average relaxation times <τ> were obtained from the integral of the relaxation function and were found to follow the relation <τ>=Aexp(B/(T−T0)), where for our sample B=2940K and T0=273K. The observed relaxation function decayed over a wider time range as the sample was cooled. Quantitative analysis of this effect using the Williams-Watts empirical function yielded a decrease in β from 0.35 at 90 C to 0.18 at 65 C. The relaxation functions were also analyzed to give a distribution of relaxation rates. The observed distributions were bimodal at 70 and 80 C. The two features behaved in a manner consistent with the primary and secondary relaxations observed for methacrylate polymers by other techniques.
This paper discusses the development of a novel selective electroless copper metallisation route for the plating of epoxy substrates. This has the potential for the development of a more cost effective and environmentally friendly plating process than currently available technologies. The electroless process required that the electrically insulating epoxy substrate was initially activated to catalyse the reduction of the copper (I1) salt which was in solution to a copper (0) deposit. Selective activation was achieved by coating the epoxy substrates with a new proprietary palladium compound and selectively exposing specific areas to 222nm radiation from a KrCI* excimer lamp. It has been shown that only the palladium metal and not the proprietary precursor catalyse the reaction. After selective seeding the patterned epoxy substrates were copper plated in a commercial electroless copper bath. The process conditions and effect of surface preparation on the quality and resolution of the selectively deposited copper patterns are discussed.
Photocurrent spectroscopy of InAs/GaAs self-assembled quantum dots, studied as a function of applied electric field, is used to probe the nature of the confined electronic states. A field asymmetry of the quantum confined Stark effect is observed, consistent with the dots possessing a permanent dipole moment. The sign of this dipole indicates that for zero field the hole wavefunction lies above that of the electron, in disagreement with the predictions of all recent calculations. Comparison with a theoretical model demonstrates that the experimentally determined alignment of the electron and hole can only be explained if the dots contain a nonzero and non-uniform Ga content. The role of two different carrier escape mechanisms, tunneling and thermal excitation, is studied.
Sheet resistance (Rs) reductions are presented for antimony and arsenic doped layers produced in strained Si. Results re-emphasise the Rs reduction for As comes purely as a result of mobility improvement whereas for Sb, a superior lowering is observed from improvements in both mobility and activation. For the first time, strain is shown to enhance the activation of dopant atoms whilst Sb is seen to create stable ultra-shallow junctions. Our results propose Sb as a viable alternative to As for the creation of highly activated, low resistance ultra-shallow junctions for use with strain-engineered CMOS devices.