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The Hector Galaxy Survey is a new optical integral field spectroscopy (IFS) survey currently using the Anglo-Australian Telescope to observe up to 15 000 galaxies at low redshift (
$z \lt 0.1$). The Hector instrument employs 21 optical fibre bundles feeding into two double-beam spectrographs, AAOmega and the new Spector spectrograph, to enable wide-field multi-object IFS observations of galaxies. To efficiently process the survey data, we adopt the data reduction pipeline developed for the SAMI Galaxy Survey, with significant updates to accommodate Hector’s dual-spectrograph system. These enhancements address key differences in spectral resolution and other instrumental characteristics relative to SAMI and are specifically optimised for Hector’s unique configuration. We introduce a two-dimensional arc fitting approach that reduces the root-mean-square (RMS) velocity scatter by a factor of 1.2–3.4 compared to fitting arc lines independently for each fibre. The pipeline also incorporates detailed modelling of chromatic optical distortion in the wide-field corrector, to account for wavelength-dependent spatial shifts across the focal plane. We assess data quality through a series of validation tests, including wavelength solution accuracy (1.2–2.7 km s
$^{-1}$ RMS), spectral resolution (FWHM of 1.2–1.4 Å for Spector), throughput characterisation, astrometric precision (
$\lesssim$ 0.03 arcsec median offset), sky subtraction residuals (1–1.6% median continuum residual), and flux calibration stability (4% systematic offset when compared to Legacy Survey fluxes). We demonstrate that Hector delivers high-fidelity, science-ready datasets, supporting robust measurements of galaxy kinematics, stellar populations, and emission-line properties and provide examples. Additionally, we address systematic uncertainties identified during the data processing and propose future improvements to enhance the precision and reliability of upcoming data releases. This work establishes a robust data reduction framework for Hector, delivering high-quality data products that support a broad range of extragalactic studies.
To examine the evidence as to whether the relationship between undernutrition and poor child development is causal.
Selected studies from developing countries were discussed. Observational studies were first considered then experimental studies of preventative and remedial supplementation. The type of functions affected, the presence of sensitive periods and the role of protein and energy versus that of micronutrients were reviewed.
Childhood undernutrition is generally associated with concurrent and longer term deficits in cognition, behaviour and motor skills, although the relationship is likely to be confounded by socio-economic factors. Supplementation trials have had many design problems. However, those beginning at any age from pregnancy up to 24 months have consistently had concurrent benefits suggesting a causal relationship. Supplement begun in older children had little or no effect, albeit there are too few studies to conclude with confidence. The limited evidence suggests that benefits are more likely to be sustained if supplementation begins in late pregnancy or at birth and is continued until the child is at least 24 months old.
Deficits in cognition tend to be global and there is insufficient evidence of specific deficits. There is some evidence that the first 2 years of life are most sensitive to the effects of undernutrition. Most studies have failed to separate the effects of energy and protein from those of micronutrients. One study showed that energy and/or protein affects children's development. Psychosocial stimulation has had consistent benefits on undernourished childrens' development
Public health nutrition programmes should include a component in which children who are at risk are targeted during the first 2 years of life with combined interventions involving nutrition, health care and early stimulation.
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