Weight faltering and failure to thrive in infancy and early childhood

Weight faltering, or failure to thrive, is a childhood condition that provokes concern about possible neglect, deprivation, and organic illness. However, research over the past 20 years has brought the validity of this concern into question, leading to the proposal that management should be less aggressive.We summarise the evidence base, discuss new developments, and provide a practical approach to management. Failure to thrive has been defined in a range of ways, with no overall accepted definition but an essential element is subnormal growth or weight gain, hence the increasing use in recent years of the term weight faltering

Thermoregulation and energy metabolism in the lesser bushbaby, Galago senegalensis moholi

Thermoregulation and energy metabolism were studied in adult and juvenile G. s. moholi at ambient temperatures ranging from 6 to 35°C. In the adults, oxygen consumption decreased with increasing ambient temperature reaching minimum values of 0,7 ± 0,04 (males) and 0,9 ± 0,04 ml O2 g−1 h−1 (females) at the lower critical temperature of 28°C. Between 28 and 35°C, the thermal neutral zone, oxygen consumption remained constant and was found to be 32% (males) and 16% (females) below the theoretical mass specific level. In the juveniles oxygen consumption also decreased with increasing temperature but reached the lowest measured value at 35°C. Oxygen consumption in this group was significantly higher than in the adults at each temperature. Body temperature remained constant over most of the temperature range, but increased significantly in the female and juvenile groups at 35°C. Evaporative water loss increased linearly with temperature in all groups. At 35°C less than 50% of the endogenous heat production was dissipated by this means. The results are discussed with reference to the age, habitat and behaviour of the animal

Space weathering: Laboratory analyses and in-situ instrumentation

Simulations of space weathering using laser irradiation are exploited to study the formation of sub-microscopic iron. A variety of magnetic techniques are evaluated to characterise this iron and are considered for in-situ instrumentation

Practice pointer: Using the new UK-WHO growth charts

The new UK growth charts for children aged 0-4 years (designed using data from the new WHO standards) describe the optimal pattern of growth for all children, rather than the prevailing pattern in the UK (as with previous charts). The new charts are suitable for all ethnic groups and set breast feeding as the norm. UK children match the new charts well for length and height, but after age 6 months fewer children will be below the 2nd centile for weight or show weight faltering, and more will be above the 98th centile. The new charts look different: they have a separate preterm section, no lines between 0 and 2 weeks, and the 50th percentile is no longer emphasised. The charts give clear instructions on gestational correction, and there is a new chart for infants born before 32 weeks’ gestation. The instructions advise on when and how to measure and when a measurement or growth pattern is outside the normal range. The charts include a “look-up” tool for determining the body mass index centile from height and weight centiles without calculation and aid for predicting adult height. The charts and supporting educational materials can be downloaded from www.growthcharts.rcpch.ac.u

Measurement practices in hallucinations research

Introduction In several sub-fields of psychology, there has been a renewed focus on measurement practices. As far as we are aware, this has been absent in hallucinations research. Thus, we investigated (a) cross-study variation in how hallucinatory experiences are measured and (b) the reliability of measurements obtained using two tasks that are widely employed in hallucinations research. Method In Study 1, we investigated to what extent there was variation in how the Launay-Slade Hallucination Scale (LSHS) has been used across 100 studies. In Study 2, we investigated the reliability of the measurements obtained through source monitoring and signal detection tasks, using data from four recent publications. Materials/data are available at doi: 10.17605/osf.io/d3gnk/. Results In Study 1, we found substantial variation in how hallucinatory experiences were assessed using the LSHS and that descriptions of the LSHS were often incomplete in important ways. In Study 2, we reported a range of reliability estimates for the measurements obtained using source monitoring and signal discrimination tasks. Some measurements obtained using source monitoring tasks had unacceptably low levels of reliability. Conclusions Our findings suggest that suboptimal measurement practices are common in hallucinations research and we suggest steps researchers could take to improve measurement practices

Changes in the UK baby food market surveyed in 2013 and 2019: the rise of baby snacks and sweet/savoury foods

Objective: To assess how the baby food market in the UK has changed between 2013 and 2019. Setting: United Kingdom. Design: A cross-sectional survey of all infant food products available to buy in the UK online and in-store collected in 2019. Nutritional content and product descriptions were recorded and compared with an existing 2013 database. Main outcome measures: Change in the proportion of products marketed to infants aged 4 months, proportion classified as sweet versus savoury, spoonable versus dry (snacks) average sugar content. Results: Fewer products were described as suitable for infants aged 4 months in 2019 (201, 23%) compared with 2013 (178, 43%; p<0.001), while the proportion for children in the 6–7-month age range increased (2013: 135, 33%; 2019: 369, 43%; p=0.001). The proportion of sweet and savoury products was unchanged; sweet spoonable products showed a small but significant decrease in sugar content (6%) between 2013 and 2019, but savoury spoonable products showed a 16% increase. Sweet snacks remained very sweet (~20 g/100 g median sugar at both time points). In the 2019 dataset, concentrated juice was added to 29% (n=253) of products and 18% (n=80) ‘savoury’ products comprised more than 50% sweet vegetables or fruit. The number and proportion of snacks increased markedly in 2019 (185, 21%) compared with 2013 (42, 10%; p=0.001) while the proportion of wet spoonable foods decreased (2013: 326, 79%; 2019: 611, 71%; p=0.001). Conclusions: Fewer foods are now marketed to infants aged 4 months, but there has been no overall reduction in the sweetness of products and the increase in snack foods and the sweetness of savoury foods is a concern

Ground-based detection of a vibration-rotation line of HD in Orion

The v =1-0 R(5) line of HD at 2.46um has been detected at the position of brightest line emission of shocked H2 in the Orion Molecular Cloud. The flux in this HD line, when compared to that of the previously detected HD 0--0 R(5) line at 19.43um, suggests that, like the v=1 levels of H2, the v=1 levels of HD are populated in LTE, despite their much higher rates of spontaneous emission compared to H2. The higher than expected population of vibrationally excited HD may be due to chemical coupling of HD to H2 via the reactive collisions HD + H H2 + D in the shocked gas. The deuterium abundance implied by the strengths of these lines relative to those of H2 is (5.1 pm 1.9 x 10^-6.Comment: 9 pages, 2 figures, Proceedings of the Conference on "Deuterium in the Universe," to be published in Planetary and Space Science

Lyapunov exponents for products of complex Gaussian random matrices

The exact value of the Lyapunov exponents for the random matrix product $P_N = A_N A_{N-1}...A_1$ with each $A_i = \Sigma^{1/2} G_i^{\rm c}$, where $\Sigma$ is a fixed $d \times d$ positive definite matrix and $G_i^{\rm c}$ a $d \times d$ complex Gaussian matrix with entries standard complex normals, are calculated. Also obtained is an exact expression for the sum of the Lyapunov exponents in both the complex and real cases, and the Lyapunov exponents for diffusing complex matrices.Comment: 15 page

Properties of Pt Schottky Type Contacts On High-Resistivity CdZnTe Detectors

In this paper we present studies of the I-V characteristics of CdZnTe detectors with Pt contacts fabricated from high-resistivity single crystals grown by the high-pressure Brigman process. We have analyzed the experimental I-V curves using a model that approximates the CZT detector as a system consisting of a reversed Schottky contact in series with the bulk resistance. Least square fits to the experimental data yield 0.78-0.79 eV for the Pt-CZT Schottky barrier height, and <20 V for the voltage required to deplete a 2 mm thick CZT detector. We demonstrate that at high bias the thermionic current over the Schottky barrier, the height of which is reduced due to an interfacial layer between the contact and CZT material, controls the leakage current of the detectors. In many cases the dark current is not determined by the resistivity of the bulk material, but rather the properties of the contacts; namely by the interfacial layer between the contact and CZT material.Comment: 12 pages, 11 figure