Managing multifunctional landscapes: Local insights from a Pacific Island Country context.

Across Pacific Island Countries, projects and policies are incorporating objectives related to managing landscape multifunctionality to sustain flows of multiple, valued ecosystem services. Strategies to manage natural resources are often not effective, or do not have intended outcomes, if they do not account for local contexts and the varied needs and constraints of stakeholders who rely upon natural resources for their livelihoods. Through fieldwork in Ba, Fiji, local insights were generated concerning the institutional, geographic, and socio-economic factors which determine and challenge i) different stakeholders' ability to access landscape resources, and ii) stakeholders' capacities to benefit from ecosystem services. The following insights were generated from this research which are important for guiding management of landscape multifunctionality. In Ba, hierarchical governance systems present barriers to effective management of landscape multifunctionality, and projects or policies with aims to manage landscapes should establish context appropriate multi-scale governance. Such governance systems should facilitate communication and interaction between different stakeholders, build upon community knowledge, and support communities as key actors in landscape management. Consideration of the spatial footprint of landscape resources, stakeholders' different physical and financial capacities, and the institutional structures that mediate access to resources should be central to landscape management and planning. Various climatic stressors affect flows of ecosystem services from the Ba landscape and people's capacity to access landscape resources; therefore, it is important that management of landscapes also builds resilience to climate stressors.

The efficacy of high-throughput sequencing and target enrichment on charred archaeobotanical remains.

The majority of archaeological plant material is preserved in a charred state. Obtaining reliable ancient DNA data from these remains has presented challenges due to high rates of nucleotide damage, short DNA fragment lengths, low endogenous DNA content and the potential for modern contamination. It has been suggested that high-throughput sequencing (HTS) technologies coupled with DNA enrichment techniques may overcome some of these limitations. Here we report the findings of HTS and target enrichment on four important archaeological crops (barley, grape, maize and rice) performed in three different laboratories, presenting the largest HTS assessment of charred archaeobotanical specimens to date. Rigorous analysis of our data - excluding false-positives due to background contamination or incorrect index assignments - indicated a lack of endogenous DNA in nearly all samples, except for one lightly-charred maize cob. Even with target enrichment, this sample failed to yield adequate data required to address fundamental questions in archaeology and biology. We further reanalysed part of an existing dataset on charred plant material, and found all purported endogenous DNA sequences were likely to be spurious. We suggest these technologies are not suitable for use with charred archaeobotanicals and urge great caution when interpreting data obtained by HTS of these remains.

Early Levallois technology and the Lower to Middle Paleolithic transition in the Southern Caucasus.

The Lower to Middle Paleolithic transition (~400,000 to 200,000 years ago) is marked by technical, behavioral, and anatomical changes among hominin populations throughout Africa and Eurasia. The replacement of bifacial stone tools, such as handaxes, by tools made on flakes detached from Levallois cores documents the most important conceptual shift in stone tool production strategies since the advent of bifacial technology more than one million years earlier and has been argued to result from the expansion of archaic Homo sapiens out of Africa. Our data from Nor Geghi 1, Armenia, record the earliest synchronic use of bifacial and Levallois technology outside Africa and are consistent with the hypothesis that this transition occurred independently within geographically dispersed, technologically precocious hominin populations with a shared technological ancestry.

Human immunodeficiency virus and pregnancy.

There are now proven ways to reduce the transmission of human immunodeficiency virus from infected mothers to their offspring, including the use of zidovudine during pregnancy and labour, and avoidance of breast-feeding. Therefore, screening programmes should be extended to enable at-risk mothers to benefit from these advances.

Hormone studies in Myxine glutinosa: failure of calcitonin to influence urine flow or plasma and urine electrolyte balance.

Hagfish, Myxine glutinosa, were used in a series of experiments to determine a possible role for calcitonin in plasma and urine electrolyte balance. Individual animals were anaesthetised and implanted with polythene cannulae for monitoring blood pressure and for infusion/injection. Urine was collected by manual palpation of the body surface whilst blood samples were withdrawn from the lateral sinus. Following injection of either 1.25 or 3.75 micrograms kg body wt-1 calcitonin, there was no significant change in either the plasma or urine composition of sodium, potassium, calcium, or magnesium ion levels. These results indicate that calcitonin may not be involved in electrolyte homeostasis in Myxine.

Hormone studies in Myxine glutinosa: effects of the eicosanoids arachidonic acid, prostaglandin E1, E2, A2, F2 alpha, thromboxane B2 and of indomethacin on plasma cortisol, blood pressure, urine flow and electrolyte balance.

Hagfish, Myxine glutinosa, were used in an investigation of the possible effects of various eicosanoids and the prostaglandin synthetase inhibitor indomethacin, on cortisol production, blood pressure control, urine flow and electrolyte balance. Cortisol levels in plasma of untreated control animals and plasma from animals 1 h following injection of 50 micrograms kg-1 prostaglandin E1, E2, A2, F2 alpha TXB2 and indomethacin were not detectable. However, plasma cortisol levels rose to between 10 and 26 pg ml-1 1 h following injection of either 50 micrograms kg-1 arachidonic acid or prostaglandin E2. This rise was similar in magnitude to that produced 1 h following administration of 50 micrograms kg-1 porcine ACTH. The resting dorsal aortic blood pressure of between 3.50 and 3.75 mmHg was reduced on average by 50% for 12-15 min when animals received 10 micrograms kg-1 arachidonic acid, prostaglandin E1, E2, A2, and TXB2 and was effectively reduced to zero for 20 min or more following 50 micrograms kg-1 of these eicosanoids. Similar doses of prostaglandin F2 alpha, however, evoked an increase in blood pressure (19-33%) whilst indomethacin was without effect. Control measurements of urine flow in Myxine were estimated to be between 540 and 660 microliters h-1 kg-1. There was a marked reduction in urine output following the arterial vasodepression induced by arachidonic acid, prostaglandin E1, E2, A2 and TXB2 in doses of 10 micrograms kg-1, an effect which became even more pronounced following injection of 50 micrograms kg-1 quantities, leading in some cases to complete anuria.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic, renal, and steroidogenic actions of prostaglandins E1, E2, A2, and F2 alpha in European eels.

Seawater-adapted eels were implanted with both venous and arterial cannulae and catheterised. Prostaglandin in 0.9% glucose saline was given either by 10 microliters injection or by infusion (40 ng/min) while blood pressure recordings and blood samples were taken from the dorsal aorta. Glomerular filtration rates were calculated from the clearance of [3H]inulin, renal plasma flow from the clearance of PAH, and functional tubular mass from measurements of glucose reabsorption maxima (TmG). Cortisol levels were measured by radioimmunoassay. Injections of prostaglandin E1, E2, and A2 (0.01-10 ng/kg body wt) induced transient reductions in dorsal aortic blood pressure whilst concentrations of between 10 and 100 ng/kg body wt caused both prolonged vasodepression and glomerular antidiuresis, with decreased TmG and CPAH. Fractional excretion of electrolytes remained unchanged. Doses of 10-50 micrograms/kg body wt caused an initial glomerular diuresis, increased TmG and CPAH but were without effect on the fractional excretion of the filtered load. This diuretic action was followed by a longer period of antidiuresis. The vasodepression during 24 hr prostaglandin infusion became less severe after an initial 2-hr period, indicating a degree of tachyphylaxis. Prostaglandin F2 alpha in doses of 10-50 micrograms/kg body wt was slightly vasopressor but with no obvious effect on kidney function. All prostaglandins so far used, given either by infusion or injection caused a significant increase in cortisol production. These results suggest that prostaglandins may play similar roles throughout a range of vertebrates.

Depression of sodium, chloride and calcium ions in the plasma of goldfish (Carassius auratus) and immature freshwater- and seawater-adapted eels (Anguilla anguilla L.) after acute administration of salmon calcitonin.

Goldfish showed a significant reduction in their plasma sodium and calcium levels 1 h after receiving 50 i.u. calcitonin per kg body weight. When 100 i.u. calcitonin were injected there was a significant fall in circulating levels of both sodium and calcium and also of chloride ions compared with those found in untreated control animals. Administration of calcitonin to immature eels adapted to either freshwater or seawater conditions showed no significant change in plasma ion composition at doses of 10 i.u. per kg body weight or less. However, doses of 50 and 100 i.u. caused significant reductions in plasma sodium, chloride and calcium ion levels compared with sham-injected control animals. When immature eels were given 100 i.u. calcitonin per kg body weight there were significant reductions in the plasma levels of sodium, chloride and calcium ions but the timing of these changes was slightly different. In freshwater-adapted eels, the depression of plasma sodium was seen after 30 min and lasted for up to 2 h, whilst depression of plasma chloride and calcium was not seen until 1 h after injection. In addition, whilst the lowering of plasma chloride ions lasted up to 2 h after injection, the plasma calcium had returned to the preinjection control level by this time. In seawater-adapted eels the depression of sodium, chloride and calcium levels was seen at 30 min and the effect continued for up to 2 h after injection when the depression was no longer apparent.