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The study of tree rings has been used for over 100 years to inform climatic and geomorphological reconstructions. In mainland Australia, no tree species are currently recognised as providing reliable sources for such studies over extensive areas. Eucalyptus camaldulensis is a widely growing species with a growth pattern that is closely linked to high levels of available moisture, such as that associated with floods. The species therefore has the potential to provide palaeoclimatic information that may be of use in hydrological and geomorphological studies. This study initially examines the microstructure of samples of E. camaldulensis taken from the Barmah Forest to assess the applicability of the species to dendroecological investigation. It is found that samples of the species exhibit ring-like structures, although there are areas of the samples that contain zones of growth without clear ring boundaries. The patterns of growth rings and zones are found to be common to many trees at a site, although the level of variability of pattern from tree to tree is high. Options for future development of the approach described here are to combine ring studies with isotopic-based analysis to provide a combination of tree age and climatic history.

This paper summarises seawatching data collected from the Isle of Tiree in 2001-18. Seawatches were conducted whenever conditions appeared favourable for seabird passage and were thus not conducted in a standardised way, although all counts were converted to mean hourly rates of passage per day. Results included record Scottish mean hourly rates of passage o f24,380 Manx Shearwaters off Aird on 22 June 2 0 06 and of 6,900-7,000 Razorbills off Aird on 3 -4 October 2003, plus record Argyll mean hourly rates of passage of 178 Storm Petrels off Hynish on 17 August 2005, 1,200 Cannets off Aird on 3 October 2003 and 1,320 Fulmars off Hynish on 13 September2004. A late winter mean hourly rate of passage o f 3,650 Kittiwakes off Aird on 2 February 2016 was exceptional in a Scottish context and equalled the record Argyll hourly rate of passage. There was also an unexpectedly large annual autumn movement of Great Skuas out of the Minch, including a record Argyll mean hourly rate o f passage of 41 off Aird on 16 September 2013. [ABSTRACT FROM AUTHOR]

The article discusses a research concerning the population of Vagrant Nearctic waders in Argyll, Scotland. It highlights that Inner Hebrides island in Argyll is rich with wetlands, shallow lochs and seaweed-rich shores which are significant to numbers of breeding birds such as Corncrakes and wet grassland waders. It also emphasizes that Tiree serves as migratory staging point for waders in Iceland, Greenland and Canada.

The article reports on the sighting of a first-winter Cedar Waxwing in the Isle of Tiree, Argyll, from September 23-28, 2013. It mentions the bird consuming the berries of a Contoneaster bush in a garden, the distress of the garden owner at the possibility of excited birders coming to see it, and the improvement of the state of the bird from lethargic to alert. Also included are descriptions of its shape, size and plumage, and the status of the bird species in Scotland.

The author reports on his sighting of a Brown Shrike on Tiree in the isle of Argyll from October to November 2011. He observed the shrike perched on a neighbor's garden. He describes the color of the bird's upperparts, underparts, breast and flanks. He notes several significant features of the parts of the bird including its tertials, wings, tail, head and bill. A description of the bird's shape and size and plumage is presented.

The article offers information on black-tailed Godwits Limosa limosa which was found on the Isle of Tiree in Argyll, Scotland. Godwits are characterized as typically tall, long-legged and long-billed wader, with elegant proportions. Their bodies are longer and slimmer than an adjacent islandica. Godwits have an overall warmer and browner look compared to adjacent silvery-greyish-toned first-summer islandica.

Growth parameters of Agrostis capillaris L. and Nardus stricta L. were measured in relation to ambient and elevated concentrations of CO2 (340 and 550 μl CO2l-1, respectively) and at low and high concentrations of nitrogen (0.8 and 3 mM NH4NO3, respectively). After 60 d of growth A. capillaris had attained approx, four times the total dry weight of N. stricta in all treatments, which was attributed to the greater leaf area ratio of the former. A. capillaris grown at the low nitrogen concentration attained 30 % of the total dry weight of plants grown at high nitrogen. Over the 60 d period, destructive harvests (seven in total) showed the growth of N. stricta to be less sensitive than that of A. capillaris to the concentration of nitrogen, but in both species growth analysis showed the lower total dry weight at low nitrogen to be attributable to lower unit leaf rate. There was a differential response of both species to elevated concentrations of CO2 which was nitrogen dependent. A. capillaris grown at elevated CO2 attained a greater total dry weight than at ambient CO2 and this response was proportionately greater at low nitrogen (78 % increase) than at high nitrogen (58 °o increase). In contrast, in N. stricta there was no effect of CO2 concentration on the total dry weight at low nitrogen whilst at high nitrogen plants grown at elevated CO2 had a greater total dry weight after 48 d of growth. Calculation of the allometric coefficient (K) relating root growth to shoot growth indicated that the effect of the lower nitrogen concentration was to increase partitioning to the roots while the higher CO2 concentration did not alter partitioning. [ABSTRACT FROM AUTHOR]

The technique of X-ray microanalysis was used to study the composition of toad urinary bladder epithelial cells incubated in Na Ringer's and K-free medium, with and without ouabain. Following incubation under short-circuit conditions, portions of tissue were coated with an external albumin standard and plunge-frozen. Cryosections were freeze-dried and analyzed. In Na Ringer's, granular and basal cells, and also the basal portion of the goblet cells, had similar water and ion compositions. In contrast, mitochondria-rich cells contained less Cl and Na. On average, the granular cells and a subpopulation of the basal cells lost K and gained Na after ouabain and in K-free medium alone. However, there was considerable variation from cell to cell in the responses, indicating differences between cells in the availabilities of ion pathways, either as a consequence of differences in the numbers of such pathways or in their control. In contrast, the compositions of both the low Cl, mitochondria-rich cells and a sub-population of the basal cells were little affected by the different incubation conditions. This is consistent with a comparatively low Na permeability of these cells. The results also indicate that (i) much, if not all, of the K in the dominant cell type, the granular cells, is potentially exchangeable with serosal medium Na, and (ii) Na is accumulated from the serosal medium under K-free conditions. They also provide information about the role of the (Na-K)-ATPase in the maintenance of cellular K in K-free medium, being consistent with other evidence that removal of serosal medium K inhibits transepithelial Na transport by decreasing Na entry to the cells from the mucosal medium, rather than solely by inhibiting the basolateral membrane (Na-K)-ATPase. [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's experience of sighting the Collared Flycatcher on May 27, 2014 in Tiree, Argyll, Scotland as the first recorded sighting of the bird in southwest Scotland.

The response of the villus and crypt cells of the mouse jejunum to secretagogues has been assessed through measurements of cellular composition with x-ray microanalysis. In nonstimulated tissues the Na concentration ([Na]c) of the crypt cells was significantly less, and the K ([K]c) and Cl ([Cl]c) concentrations were significantly greater, than that of the villus cells. There was also a decreasing gradient of [Na]c and increasing gradient of [K]c from the villus tip to crypt base due to a greater number of cells with a high [Na]c and low [K]c in the upper regions of the villi. Theophylline (10 mmol L-1) stimulated a sustained increase in bumetanide sensitive short circuit current (Isc) and significantly decreased the [Na]c of the villus cells. Similar, but smaller changes were seen in the crypt cells. Changes in villus cell [Na]c reflected a reduction in the number of cells with a high [Na]c. Inhibition of the apical Na/H exchanger (1 mmol L-1 amiloride) had little effect on basal Isc and the subsequent addition of theophylline increased Isc to a comparable extent as seen without amiloride. However, after amiloride treatment the only change in cellular composition was a reduction in the [Cl]c of both crypt and villus cells, suggesting that both regions are involved in the secretory response. These data suggest that the dominant response of the jejunum to secretagogues is an inhibition of Na absorption via Na/H exchange in the villi and the secretory response is distributed throughout the crypt/villus axis.

Growth and photosynthesis of Agrostis capillaris L. and Nardus stricta L. were measured for plants grown under ambient and elevated concentrations of CO2 (340 and 550 μl CO2 l(-1) respectively) and a range of nitrogen concentrations (0.01, 0.1, 1 and 5 mg N l(-1) ) supplied as either ammonium sulphate or sodium nitrate. After 42 d of growth for A. capillaris and 49 d of growth for N. stricta, the higher nitrogen concentrations resulted in stimulation of growth. The form of nitrogen did not affect the total dry weight attained by A. capillaris. However, ammonium-grown N. stricta attained a greater total dry weight than did nitrate-grown plants. Nitrogen form influenced leaf area ratio, which was greater in nitrate-grown A. capillaris and in ammonium-grown N. stricta. At the two lowest nitrogen concentrations there was no effect of elevated CO2 on total dry weight in either species, whilst at the two highest nitrogen concentrations positive growth responses to elevated C02 were observed. Photosynthetic capacity and carboxylation efficiency were lower in plants grown in elevated CO2 at the two lowest nitrogen concentrations, and were associated with greater leaf soluble carbohydrate content and lower foliar nitrogen concentrations. By contrast, the CO2 treatment did not affect these parameters at the two highest nitrogen concentrations employed.

Rabbit iris-ciliary bodies were preincubated in control and experimental Ringer's solutions before quick freezing, cryosectioning, dehydration and electron probe X-ray microanalysis. After preincubation in a baseline bicarbonate-free Cl- Ringer's solution, the ciliary epithelial intracellular Na+, K+ and Cl- concentrations were estimated to be 15 +/- 3, 162 +/- 14 and 46 +/- 5 mmol kg-1 intracellular water, respectively. The water and elemental Na, K, Cl and P contents were similar in the non-pigmented (NPE) and pigmented (PE) ciliary epithelial cells. As expected, inhibition of the Na,K-exchange pump by preincubation with ouabain markedly increased the intracellular Na content, and markedly reduced the intracellular K content, verifying the validity of the experimental analysis. The Cl- channels of the NPE cells likely play a critical role in determining the rate of aqueous humor formation. Therefore, we have examined the effects of altering Cl- transport on the intracellular composition in this initial microprobe study of the ciliary epithelium. As expected, exposure to bicarbonate increased the intracellular Cl and water contents. Replacement of external Cl- by NO3- was twice as effective as replacement by gluconate in leaching Cl- out of the intracellular compartment. An unexpected finding was that NO3- replacement of internal Cl- substantially increased the intracellular Na and decreased the intracellular K content, possibly by stabilizing the Na,K-pump in the E1P form and inhibiting enzyme activity.