The social context of childcare practices and child malnutrition in Niger's recent food crisis

In 2004–05, Niger suffered a food crisis during which global attention focused on high levels of acute malnutrition among children. In response, decentralised emergency nutrition programmes were introduced into much of southern Niger. Child malnutrition, however, is a chronic problem and its links with food production and household food security are complex. This qualitative, anthropological study investigates pathways by which children are rendered vulnerable in the context of a nutritional 'emergency'. It focuses on household-level decisions that determine resource allocation and childcare practices in order to explain why practices apparently detrimental to children's health persist. Risk aversion, the need to maintain self-identity and status, and constrained decision making result in a failure to invest extra necessary resources ingrowth-faltering children. Understanding and responding to the social context of child malnutrition will help humanitarian workers to integrate their efforts more effectively with longer-term development programmes aimed at improving livelihood security.     

Tissue accumulation of aluminium is not a predictor of toxicity in the freshwater snail, Lymnaea stagnalis

The amount of toxic metal accumulated by an organism is often taken as an indicator of potential toxicity. We investigated this relationship in the freshwater snail, Lymnaea stagnalis, exposed to 500 μg l⁻¹ Al over 30 days, either alone or in the presence of phosphate (500 μg l⁻¹ P) or a fulvic acid surrogate (FAS; 10 mg l⁻¹ C). Behavioural activity was assessed and tissue accumulation of Al quantified. Lability of Al within the water column was a good predictor of toxicity. FAS increased both Al lability and behavioural dysfunction, whereas phosphate reduced Al lability, and completely abolished Al-induced behavioural toxicity. Tissue accumulation of Al was not linked to toxicity. Higher levels of Al were accumulated in snails exposed to Al + P, compared to those exposed to Al alone, whereas FAS reduced Al accumulation. These findings demonstrate that the degree of tissue accumulation of a metal can be independent of toxicity.     

Differences in resistance of three subtropical vegetation types to experimental trampling

Experimental trampling trials using a standardized methodology were undertaken in 10 replicate blocks in three vegetation types in an urban reserve in the subtropics of Australia. In each block different intensities of trampling (controls, 10, 25, 50, 100, 150, 200, 250, 300, 400 and 500 passes) were applied, and vegetation parameters were measured pre-trampling, immediately after trampling and 2 weeks later. A Fern understorey had low resistance to trampling intensity, with reductions in relative vegetation height and cover with as few as 10 passes. A Tussock grass understorey showed moderate resistance with reduction in height at 25 passes and cover at 50 passes. A Disturbed grassland dominated by lawn grasses had the highest resistance, with reductions in vegetation height at 100 passes, but cover was affected by as few as 10 passes. The resistance indices (number of passes required to reduce vegetation cover by 50%) of three vegetation types were 210, 360 and 860 passes, respectively. When these values were compared with those for 52 other vegetation types considerable variation was found within life forms, climatic zones and vegetation types indicating that the response of a specific community may not always be predictable.     

Wool-waste as organic nutrient source for container-grown plants

A container experiment was conducted to test the hypothesis that uncomposted wool wastes could be used as nutrient source and growth medium constituent for container-grown plants. The treatments were: (1) rate of wool-waste application (0 or unamended control, 20, 40, 80, and 120 g of wool per 8-in. pot), (2) growth medium constituents [(2.1) wool plus perlite, (2.2) wool plus peat, and (2.3) wool plus peat plus perlite], and (3) plant species (basil and Swiss chard). A single addition of 20, 40, 80, or 120 g of wool-waste to Swiss chard (Beta vulgaris L.) and basil (Ocimum basilicum L.) in pots with growth medium provided four harvests of Swiss chard and five harvests of basil. Total basil yield from the five harvests was 1.6–5 times greater than the total yield from the unamended control, while total Swiss chard yield from the four harvests was 2–5 times greater relative to the respective unamended control. The addition of wool-waste to the growth medium increased Swiss chard and basil tissue N, and NO₃–N and NH₄–N in growth medium relative to the unamended control. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) microanalysis of wool fibers sampled at the end of the experiments indicated various levels of decomposition, with some fibers retaining their original surface structure. Furthermore, most of the wool fibers’ surfaces contained significant concentrations of S and much less N, P, or K. SEM/EDX revealed that some plant roots grow directly on wool-waste fibers suggesting either (1) root directional growth towards sites with greater nutrient concentration and/or (2) a possible role for roots or root exudates in wool decomposition. Results from this study suggest that uncomposted wool wastes can be used as soil amendment, growth medium constituent, and nutrient source for container-grown plants.     

Lactation,maternal behavior and infant growth in common marmoset monkeys (<Emphasis Type="Italic">Callithrix jacchus</Emphasis>): effects of maternal size and litter size

We examined the relationship between lactation performance and infant growth in a captive population of common marmosets (Callithrix jacchus) that varied in both maternal and litter size. Though common marmosets display a typical primate pattern of dilute milk and relatively slow infant growth rates (factors associated with low daily lactation investment and minimal maternal size effects), we hypothesized that the marmoset's small body size would make lactation investment more sensitive to maternal size than is true for larger-bodied primates. Smaller mothers rearing twins had lower milk fat, lower gross energy in milk samples collected in mid to late lactation and lower nursing-bout frequencies than did large mothers nursing twins. Lactation performance and maternal behavior did not differ between large and small mothers when rearing singletons, with a single exception: small mothers had a lower gross energy in mid-lactation milk samples. Relative growth rates in twins but not singletons were affected by maternal size, such that small mothers supported more growth per infant when rearing singletons while large mothers supported more growth per infant when rearing twins. Among the larger mothers, only, older mothers supported somewhat, though not significantly, less growth per infant, regardless of litter size. Twin infants of small mothers appeared to respond to below-optimal levels of milk yield by initiating maternal carrying less often. The relative energy intake of mothers was similar regardless of litter or maternal size. Small mothers rearing twins drew more heavily on reserves, reflected in a linear weight loss during lactation; however, the reserves drawn upon were inadequate to meet the lactation demand, resulting in lower milk energy output. In addition, small mothers rearing twins were more likely to be ill and less likely to be fertile in the year following lactation than were large mothers of twins or mothers of any size rearing singletons.     

Relationship of life-history patterns to depth in deep-water caridean shrimps (Crustacea: Natantia)

Deep-water shrimps, distributed on the steep outer reef slopes of tropical Pacific Islands, were obtained by setting baited traps in depths down to 850 m in the vicinity of Laucala Bay, Fiji, over the period 1979 to 1983. Life-history variables were estimated and interspecific comparisons made between Parapandalus serratifrons, Plesionika longirostris, Heterocarpus ensifer, H. gibbosus, H. sibogae, H. laevigatus (Pandalidae) and Saron marmoratus (Hippolytidae) which have different depth distributions. Results suggested that, interspecifically, reproductive lifespan tended to increase with increasing depth of distribution and that mean egg sizes of each species increased with increasing depth. Brood sizes tended to increase inconsistently with depth, although relative brood size (number of eggs per “standar” 15 g individual) appeared unrelated to depth. Although annual reproductive effort varied inconsistently with depth, reproductive effort totalled over the lifespan of the Heterocarpus species tended to increase with increasing depth. Some of the findings are counter to competition-based ecological theory, and it is proposed that adult predation decreases with increasing depth, allowing deeper-water species to have an extended lifespan, an increased degree of iteroparity, and a corresponding increase in lifetime reproductive effort. Further, we suggest that the probabilities of larval survival, which appear to decrease with increasing depth, are offset by the production of larger eggs by deeper-water species.     

A High Performance Liquid Chromatographic Determination of Free Amino Acids in Natural Waters in the Picomolar (M X 10-12) Range Suitable for Shipboard Use

A reliable method for the determination of amino acids, suitable for routine shipboard use, is presented. Using reverse-phase high-performance liquid chromatography with computer-controlled gradient elution optimization, the amino acids commonly found in sea-water were clearly resolved and determined at the picomole level. A procedure was also developed to enable repeat injections of sea water samples to be made without deterioration of column material or performance. Thus the analysis was made more operator-independent and consequently more suitable for use at sea.     

Amino Acids in Sea Water

Free amino acids in the waters of the English Channel have been measured over a twelve month period using a newly developed field technique. Samples have been taken over a wide area both from the surface and at depth. The results show that the levels of amino acids found in these studies are greater than those previously generally accepted. These findings are of considerable importance in productivity studies since amino nitrogen as a source of nutrient for phytoplankton has been largely neglected. This paper shows that the levels of amino acids in the upper layers of the sea are not insignificant and should not be disregarded as an alternative nitrogen source for phytoplankton.