42 resultados para Seasonal and interannual monitoring

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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A hypnotic induction technique was used to facilitate direct observation of multiple tics in a typically developing teenager in a home setting. A comprehensive habit reversal program then was implemented, including awareness training, competing response training, relaxation training, self-monitoring, social support and contingency management. Duration of relaxation was then self-monitored using a changing criterion design. The procedure eliminated multiple tics and achieved long-term maintenance of treatment gains. Implications for assessing and treating tics are discussed.

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Argulus foliaceus is a damaging fish ectoparasite for which new control measures are being developed based on egg-removal, In an attempt to develop further understanding of seasonal and vertical egg-laying patterns in this parasite, egg-laying activity was monitored over the period 14 April to 17 November 2003 in 2 rainbow trout Oncorhynchus mykiss fisheries in Northern Ireland, UK. At Site 1, egg-laying was continuous from 21 April to 17 November, when water temperature was above 8 to 10 degrees C. At Site 2, egg-laying was continuous from 4 June to 29 October. In the early months of the season, egg-laying was recorded mainly within the top 1 m of the water column; however, a significant shift to deep water egg-laying was recorded between 7 July and 17 November at Site 1 and between 20 August and 29 October at Site 2. Egg clutches were preferentially laid at depths of up to 8.5 m during this time (Site 2), a feature of egg-laying hitherto unappreciated. Temperature and dissolved oxygen did not differ significantly among depths, but there was an increase in water clarity over time. However, the precise environmental triggers for deep water egg-laying are still unclear. These new insights into the reproductive behaviour of this species will be useful in developing control methods based on egg-removal.

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Ultraviolet(UV) radiation at four wavelengths (305, 320, 340 and 380 nm) and photosynthetically active radiation (PAR) were measured from May 1994 to October 1999 using Biospherical UV radiometers. A surface reference sensor located on the roof of the Marine Station at Helgoland recorded values every 5 min, and an equivalent profiling underwater sensor was used for measurements in the sea at approximately monthly intervals. The ratio of 305-nm radiation to PAR varied seasonally, with a 14-fold increase from winter to summer. A much weaker seasonal trend (ca. 1.5-fold) was apparent in the ratio of 320-nm radiation to PAR, but there was no seasonal trend in the ratios of 340- or 380-nm radiation to PAR. The year-to-year variations in 305-nm radiation were also much greater relative to PAR than for the other UV wavelengths, but there was no evidence of a change in the 305 nm:PAR ratio over the study period. The ratios of both 305- and 320-nm radiation to PAR increased from dawn to midday, but those of 340- and 380-nm radiation were almost constant through the day, except shortly before sunrise and after sunset when the proportions of 340- and 380-nm radiation increased. Underwater measurements of PAR and UV suggest that the 1% depth for 305-nm radiation was little more than 1 m, but this estimate is valid only for summer and autumn because, in other seasons, few reliable readings for 305-nm radiation could be obtained underwater, and no attenuation coefficient could be calculated. The 1% depths recorded for the other UV wavelengths in the middle 6 months of the year were 2.0 m for 320 nm, 2.6 m for 340 nm and 4.6 m for 380 nm, compared with 12 m for PAR, but the attenuation of all wavebands increased sharply in October and remained higher until March. An analysis of the influence of sun angle, total column ozone concentration, the proportion of skylight, and cloud cover on the ratio of UV wavelengths to PAR in surface irradiance demonstrated that solar angle has a greater influence than ozone concentration on the irradiance at 305 nm, and that the typical occurrence of ozone

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Concrete structures in marine environments are subjected to cyclic wetting and drying, corrosion of reinforcement due to chloride ingress and biological deterioration. In order to assess the quality of concrete and predict the corrosion activity of reinforcing steel in concrete in this environment, it is essential to monitor the concrete continuously right from the construction phase to the end of service life of the structure. In this paper a novel combination of sensor techniques which are integrated in a sensor probe is used to monitor the quality of cover concrete and corrosion of the reinforcement. The integrated sensor probe was embedded in different concrete samples exposed to an aggressive marine environment at the Hangzhou Bay Bridge in China. The sensor probes were connected to a monitoring station, which enabled the access and control of the data remotely from Belfast, UK. The initial data obtained from the monitoring station reflected the early age properties of the concretes and distinct variations in these properties were observed with different concrete types.

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This paper examines power quality benchmarks in the electricity supply industry (ESI) and impact of standards for the reduction of voltage dip incidents. The paper considers adherence to particular standards and is supported by several case studies from incidents where voltage dips have been detected and assessed by the power systems division of Scottish Power and where improvements have been implemented to help militate against subsequent incidents.

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Soil conditioning consists of mixing and remolding the natural material during the mechanical excavation of tunnels, generally at low depth, with additives, in order to obtain suitable properties of plasticity and consistency for the excavated material, so becoming able to apply a counterpressure against natural earth pressure and groundwater flow towards the excavation chamber. The assessment and the control of the soil parameters and of machine performance are fundamental for a regular and safe excavation, also with regards to surface stability. This paper mainly focus on testing approach aimed to the proper soil conditioning with EPB shields, whose results have been validated at real scale. The influence of the water content and the amount of conditioning foam has been studied by the Authors. A proper definition of conditioning parameters can allow to extend the application field of Earth Pressure Balance (EPB) tunnel machines to various grain soil distribution, even in weak rock formations (e.g. siltstone or flysch). Importance of conditioning is reflected also on the possibility of a proper spoil disposal or better for its reuse.

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Objective: Aflatoxin is known to cross the placental barrier and exposures in utero could influence genomic programming, foetal growth and development, resulting in long-term health effects. We aimed to determine aflatoxin exposure in Gambian women at two stages of pregnancy and during the rainy and dry seasons.

Methods: We examined aflatoxin exposure in pregnant Gambian women at early (<16 weeks) and later (16 weeks onward) stages of pregnancy and at different times of the year, during the rainy (June to October 2009) or dry (November to May 2010) season, using aflatoxin–albumin adducts (AF-alb).

Results: Mean AF-alb was higher during the dry season than in the rainy season, in both early and later pregnancy although the difference was strongest in later pregnancy. There was a modest increase in AF-alb in later than early pregnancy (geometric mean 41.8 vs. 34.5 pg/mg, P < 0.05), but this was restricted to the dry season when exposures were generally higher.

Conclusions: The study confirmed that Gambian pregnant women were exposed to aflatoxin throughout the pregnancy, with higher levels in the dry season. There was some evidence in the dry season that women in later pregnancy had higher AF-alb levels than those in earlier pregnancy. Further research on the effects of exposure to this potent mutagen and carcinogen throughout pregnancy, including the epigenetic modification of foetal gene expression and impact on pre- and post-natal growth and development, are merited.