Surveys of the North American race of the Red Knot (Calidris canutus rufa) on its main wintering areas on the coasts of Patagonia and Tierra del Fuego (Argentina and Chile) showed a dramatic decline ...in the wintering population: totals in 2003 were about 30 000 compared to 67 500 in the mid-1980s. Numbers at the principal wintering site, Bahia Lomas, fell by approximately 50%, from 45 300 in 2000 to 22 000–25 000 in 2002–2003. Numbers at peripheral sites on the coast of Patagonia declined dramatically, decreasing 98% compared to numbers in the mid-1980s. The results showed that declines at core sites did not result from birds moving to other places within the known wintering (or other) areas, but reflected a general population decline, with most birds now restricted to key sites in Tierra del Fuego. This phenomenon may explain why long-term declines noted elsewhere have only recently become apparent at key wintering areas. Possible reasons for the declines are discussed. Banding studies in Delaware Bay have shown that in recent years an increasing proportion of Red Knots is unable to gain sufficient weight for migration to the breeding grounds. This is likely due to reductions in their main food resource, eggs of the horseshoe crab Limulus polyphemus. The resulting increase in mortality could account for the magnitude and severity of the declines we observed. Disminuciones en las Poblaciones Invernantes de Calidris canutus rufa en el Sur de Sur América Resumen. Censos de la raza norteamericana de Calidris canutus (rufa) en sus áreas de invernada principales en las costas de la Patagonia y Tierra del Fuego (Argentina y Chile) mostraron una disminución dramática en la población invernante. Los totales en 2003 fueron aproximadamente 30 000, comparados con 67 500 a mediados de los años 80. Los números en el sitio principal de invernada (Bahía Lomas) decayeron en aproximadamente un 50%, de 45 300 en 2000 a 22 000–25 000 en 2002–2003. Los números en sitios periféricos en la costa de Patagonia declinaron dramáticamente, en un 98% en comparación con los números de mediados de los ochenta. Los resultados mostraron que las disminuciones en los sitios núcleo no fueron el resultado de que las aves se movieran a otros sitios dentro del rango invernal conocido, o a otras áreas. En cambio, reflejaron una disminución general de la población; la mayoría de las aves están ahora restringidas a sitios claves en Tierra del Fuego. Este fenómeno podría explicar por qué las disminuciones poblacionales de largo plazo detectadas en otros lugares sólo se han hecho aparentes ahora en las áreas claves de invernada. Se discuten las posibles causas de las disminuciones. Estudios de anillamiento en la bahía de Delaware han mostrado que en años recientes una mayor proporción de las aves es incapaz de incrementar su peso hasta los niveles necesarios para la migración hacia las áreas de invernada. Esto probablemente es debido a reducciones en su principal recurso alimenticio, los huevos de Limulus polyphemus. El incremento en mortalidad resultante podría explicar la magnitud y la severidad de las disminuciones poblacionales que observamos.
Shorebirds are thought to be declining across North America but trend analyses for migrant shorebirds at interior sites in eastern North America have not been updated since the late 1990s. Data from ...a volunteer-based survey at stopover sites throughout Ontario were used to assess population trends of shorebirds over the period 1974–2009. Surveyors carried out 7,135 surveys of 258 sites and recorded 538,744 individuals of 43 shorebird species. Of 19 taxa for which trends were estimated, 17 appeared to be declining in abundance. Precision of the trend estimates was generally poor and only three declines were significant at α = 0.05. Total numbers of shorebirds recorded on surveys declined by four per cent per year, resulting in an estimated decrease in abundance of greater than 75% over the 35 years of observation. Rate of decline may be increasing for some species as declines for twelve species were larger for the period 1989–2009 vs. 1974–1989, and six species showed significant declines in the latter period whereas none did in the former period. Relating these declines in abundance at the surveyed sites to population declines is complicated by several potential sources of survey bias including changes in turnover rates and in migration timing and distributions of the species. However, given that these results are consistent with those of other migration surveys as well as those on the breeding and the wintering grounds, the most parsimonious explanation remains a widespread decline in shorebird populations.
The inclusive photoproduction of
D
∗
mesons and of
D
∗
-tagged dijets is investigated with the H1 detector at the
ep
collider HERA. The kinematic region covers small photon virtualities
Q
2
<2 GeV
2
...and photon–proton centre-of-mass energies of 100<
W
γp
<285 GeV. Inclusive
D
∗
meson differential cross sections are measured for central rapidities |
η
(
D
∗
)|<1.5 and transverse momenta
p
T
(
D
∗
)>1.8 GeV. The heavy quark production process is further investigated in events with at least two jets with transverse momentum
p
T
(jet)>3.5 GeV each, one containing the
D
∗
meson. Differential cross sections for
D
∗
-tagged dijet production and for correlations between the jets are measured in the range |
η
(
D
∗
)|<1.5 and
p
T
(
D
∗
)>2.1 GeV. The results are compared with predictions from Monte Carlo simulations and next-to-leading order perturbative QCD calculations.
Background
: There is increasing interest in using higher dosages of mesalazine for the treatment of inflammatory bowel disease; however, with current mesalazine products this involves the use of ...8–16 tablets per day.
Aim
: To evaluate the disposition, dispersion and movements of Pentasa prolonged‐release microgranules following single dosing of either tablets (2 × 500 mg) or a new 1 g sachet (unit dose, microgranules in a foil bag).
Methods
: A randomized crossover study in eight healthy volunteers was undertaken. Both formulations were radiolabelled by neutron activation and dosed in the fasted state. Location of the preparations in the bowel was assessed over 24 h by scintigraphy.
Results
: Dissolution testing at pH 7.5 showed comparable in vitro mesalazine release properties for the tablet and sachet preparations. In vivo disposition of the microgranules administered as either tablets or sachet was comparable in terms of gastric emptying, small intestinal transit and colon arrival.
Conclusions
: Pentasa sachets 1 g unit dose offers the same release of mesalazine as Pentasa 500 mg tablets. Drug release occurs throughout the gastrointestinal tract from stomach to colon, with the advantage of fewer oral doses and ease of swallowing.
Postlarval and juvenile tiger prawns (
Penaeus esculentus and
P. semisulcatus) were sampled by beam trawls in different seagrass communities of the western Gulf of Carpentaria to test the influence ...of seagrass characteristics on their distribution and abundance. Two sampling regimes were carried out: fortnightly sampling over a 3 month period during the time of peak recruitment to investigate the importance of different seagrass types to tiger prawns; and at one time to investigate the wider geographic patterns of distribution and abundance of tiger prawns. The results from both studies showed that the pattern of distribution and abundance of 1–1.9 mm carapace length (CL) postlarvae differed from those for the 2–2.9 mm CL postlarvae and juvenile tiger prawns (≥3 mm CL). The 1–1.9 mm CL size class consists of individuals that are about to settle and those that have recently settled: this size class was more widely distributed than the larger postlarvae and juveniles and was sometimes found on substrates where no seagrass was present. Larger tiger prawns were found in higher numbers on seagrass beds where the tall, broad-leaved seagrass
Enhalus acoroides was the dominant species. Although seagrass biomass was not a consistent linear predictor of juvenile tiger prawn numbers, mean catches of both the 2–2.9 mm CL postlarvae and juvenile
P. esculentus were highest when the biomass of seagrass exceeded 100 g m
−2. However, these high biomass seagrass beds contribute only 6% to the total extent of seagrasses in the shallow waters (<2.5 m deep) of the Gulf of Carpentaria. Although the numbers of juvenile tiger prawns were lower in the low-biomass seagrass beds, because of their extent, these seagrass beds are the main nurseries for sustaining the production of the valuable Northern Prawn Fishery in Australia.
In this paper we report on the first scintigraphic evaluation of vaginal dosage forms in post-menopausal women. To date, almost nothing is known about the in vivo performance of pharmaceutical ...formulations in the human vagina, which is a major deficiency in the rational design of drug delivery systems for both existing and new indications.
The vaginal spreading and clearance of a radiolabelled pessary formulation and Replens (polycarbophil) gel, was assessed in six healthy, post-menopausal female volunteers over a six hour period using the technique of gamma scintigraphy.
In five out of the six subjects studied, clearance of the two formulations exhibited very little intra-subject variation. However, there was considerable inter-subject variability in clearance; in Subject 5 circa 80% of the products were retained whilst in Subject 2 less than 2% was present at the end of the six hour imaging period. Importantly, there was no evidence to suggest that either of the formulations dispersed material beyond the cervix, into the uterus, in any of the subjects studied.
The lack of significant retention of these products in most of the volunteers has obvious implications for the delivery of therapeutic agents. This study shows that gamma scintigraphy is an invaluable technique with which to assess novel formulations aimed at optimising retention in the vagina for topical or systemic drug delivery.
A measurement is presented of the inclusive neutral current e±p scattering cross section using data collected by the H1 experiment at HERA during the years 2003 to 2007 with proton beam energies Ep ...of 920, 575, and 460 GeV. The kinematic range of the measurement covers low absolute four-momentum transfers squared, 1.5 GeV2<Q2<120 GeV2, small values of Bjorken x, 2.9⋅10−5<x<0.01, and extends to high inelasticity up to y=0.85. The structure function FL is measured by combining the new results with previously published H1 data at Ep=920 GeV and Ep=820 GeV. The new measurements are used to test several phenomenological and QCD models applicable in this low Q2 and low x kinematic domain.
PDF
