Search Results - (Author, Cooperation:P. Christie)

2013-02-22

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Air Pollutants/*analysis/metabolism/supply & distribution ; Air Pollution/*analysis/statistics & numerical data ; Animals ; China ; *Ecosystem ; Environmental Monitoring/*statistics & numerical data ; Greenhouse Effect ; Human Activities ; Humans ; Nitrates/analysis/metabolism ; Nitrogen/*analysis/metabolism ; Plants/chemistry/metabolism ; Quaternary Ammonium Compounds/analysis/metabolism

1475-2743

Blackwell Publishing Journal Backfiles 1879-2005

Geosciences

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Abstract. Soil samples from a 32-year grassland field experiment were taken from 0–5, 5–10, and 10–15 cm soil depths in February 2002. Plots received annual treatments of unamended control, mineral fertilizer, three rates of pig slurry and three rates of cow slurry, each with six replicates. Samples were analysed for cation exchange capacity (CEC), exchangeable cations (Na+, K+, Ca2+, Mg2+), pH and Olsen P. Exchangeable sodium percentage (ESP) was calculated as a sodicity indicator. Mean ESP was generally greater for slurry treatments than the control, with a trend of increasing ESP with application rate. This was particularly marked for cow slurry. At 0–5 cm depth ESP increased from 1.18 in the control to 1.75 at the highest rate of pig slurry and 5.60 at the highest rate of cow slurry. Similar trends were shown for CEC, exchangeable Na+, K+ and Mg2+, Ca2+ and Olsen P. The build-up of soil P due to slurry applications, together with this combination of physical and chemical factors, may increase the risk of P loss to surface waters, particularly from soils receiving high rates of cow slurry.

Electronic Resource

1475-2743

Blackwell Publishing Journal Backfiles 1879-2005

Geosciences

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Abstract. Organic manures are an important source of P which can make a significant economic contribution to farm fertilizer policies. In the region of 119000 tonnes of P are returned annually to UK agricultural land in the form of manures collected and handled on farms, with an estimated 66000 tonnes of P applied to tillage land and 53000 tonnes to grassland.Previous research on the utilization of manure P has tended to indicate a lower efficiency compared to inorganic fertilizer P in the season following application, but in the longer term manure and fertilizer P can be regarded as equivalent. Failure to adequately account for manure P additions to the land may result in soil enrichment which could increase the agricultural contribution to eutrophication, as a result of surface runoff or leaching.Recent research has indicated that the current guidelines for minimizing runoff losses following the land spreading of manures are generally soundly based. However, there is a need for further research where manures are applied to cracking clay soils with underdrainage, and where rainfall soon after slurry application can increase surface runoff.The careful cycling of manures within a properly devised fertilizer plan should minimize the risk of unnecessary soil P enrichment and subsequent leaching losses by restricting topsoil extractable P levels to less than 70 mg I-1.

Electronic Resource

1365-2494

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

In two field experiments acetylene (C2H2) reduction by white clover in mixed swards was compared to N2-fixed measured by 15N dilution. In both experiments, samples for C2H2 reduction were 7.5 cm diameter turves taken from plots within which microplots of 24 cm diameter were delimited and to which 15N was applied as ammonium sulphate (15NH4)2SO4). C2H2 reduction was assayed every 6–7 d. The rate of C2H2 reduction per unit length of stolon was applied to the estimated stolon length within the appropriate microplot at the time of assay, and the amount of C2H2 that would have been reduced within the microplot was estimated by integration.In experiment 1, turves taken from grass/clover swards to which 0, 1·5, 3·0, 4·5 or 6·0 g N m−2 had been applied were incubated in sealed chambers (10% C2H2, 90% air). The mean ratio of C2H2 reduced to N2 fixed during 5 weeks was 0.74:1. Application of N fertilizer lowered the proportion of assimilated N derived from N2 fixation from 95% in unfertilized swards to 83% in those receiving 6 g N m−2 (60 kg N ha−1). In experiment 2, clover roots and stolons from plots that previously had been grazed were dissected from turves and incubated in a stream of C2H2 and air (i.e. the open system). The maximum rate of ethylene (C2H4) produced during the first 12 min was taken as a measure of true nitrogenase activity. The relationship between C2H2 reduced and N2 fixed was significant (r=0.80**). The mole ratio was 0.55:1 for the 6 weeks duration of the experiment, the low ratio possibly being due to disturbance of the nodules adversely affecting acetylene reduction. Mole ratios from both experiments were well short of the theoretical 4·3:1. Using the open system does not, therefore, overcome the shortcomings of the acetylene reduction technique for measuring N2 fixation of white clover in mixed swards.

Electronic Resource

1365-2214

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Psychology

Summary Forty-nine children who had a virus infection of the central nervous system (CNS) when under 1 year of age were studied. One child had died during the initial illness and three of the survivors were severely disabled. The other survivors, more than 5 years after the initial illness, were all attending normal schools. These 45 children, together with 45 matched controls, were examined. We confirm the findings of other studies that virus infections of the CNS in infancy may cause severe disabilities in some cases, and may depress intellectual abilities in others, even though they appear to have recovered fully. Many of the children who had a virus infection of the CNS in infancy had adverse birth and social histories and so were exceptionally vulnerable, but these factors did not account fully for the findings, and when their influence was included in the analysis, the index children still had a mean performance IQ (WISC) 61 points lower than the control children (P〈0·05), whereas there was less than 1 point difference between the verbal IQs. Attention is drawn to the problem of virus infections in neonatal units.

Electronic Resource

1467-8535

Blackwell Publishing Journal Backfiles 1879-2005

Education

Electronic Resource

1365-2222

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1095-8649

Blackwell Publishing Journal Backfiles 1879-2005

Biology

The response of the brown trout to a single, short (c. 1 min) incidence of handling stress was monitored for a period of 1 month post-stress. Significant changes were found in feeding behaviour, in the levels of plasma cortisol, glucose and lactate, in the concentration of circulating lymphocytes and in the degree of epidermal mucification. No changes were detected in the growth rate and coefficient of condition, in the levels of plasma thyroxine, in the concentrations of circulating erythrocytes, neutrophils and thrombocytes or in the thickness of the epidermis. The time-course for recovery of each parameter was examined and from this it was concluded that a minimum of 2 weeks was required for complete recovery and a return to normality.

Electronic Resource

1095-8649

Blackwell Publishing Journal Backfiles 1879-2005

Biology

Hatchery-reared and wild brown trout, Salmo trutta L., were examined for skin ectoparasites during their spawning period in 1977 and 1978. A total of eight genera of parasites, comprising five ciliates, one flagellate, one monogenean and one parasitic fungus, were identified with as many as five different genera occurring on a single fish. Sexually mature male fish were more frequently or more severely infested by species of Ichthyophthirius, Scyphidia, Gyrodactylus and Saprolegnia than were immature fish of either sex or mature female fish. The differences in ectoparasitic loading could not be correlated with known, seasonal changes in the mucus-producing potential of the epidermis. These findings are discussed in relation to the defence mechanisms of teleost fish and to some of the endocrinological changes that occur in salmonid fish during the spawning season.

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] Seismic refraction and subsidence observations are used to explain the heat flow and subsidence properties of the North ...

Electronic Resource

0029-554X

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Energy, Environment Protection, Nuclear Power Engineering

Physics

Electronic Resource

0016-6480

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Medicine

Electronic Resource

1530-0358

Inflammatory bowel disease ; Urinary stone formation ; J-pouch ; Ileostomy

Springer Online Journal Archives 1860-2000

Medicine

Abstract PURPOSE: Urinary stone formation is a widely recognized complication of inflammatory bowel diseases and the surgical management of these conditions. Previously the fecal volume and chemistry after restorative proctocolectomy with J-pouch were found to be similar to conventional panproctocolectomy with permanent ileostomy. The purpose of this study was to investigate whether the relative risks of urinary stone formation were less following J-pouch than following conventional ileostomy. METHODS: The risk of urinary stone formation was determined from the chemical composition of two consecutive 24-hour urine samples in 13 patients with well-functioning ileostomies, 15 patients with well-functioning J-pouches, and 17 control volunteers. RESULTS: Compared with controls, ileostomy and J-pouch patients had significantly lowered urinary volumes and pH, higher concentrations of calcium and oxalate, and an increased risk of forming uric acid stones. In addition there was an increased risk of forming calcium stones in the conventional ileostomy group. This risk was found not to be present in the J-pouch group. CONCLUSIONS: The risks of forming uric acid stones are high for both ileostomy and J-pouch patients, but our results suggest that there will be a reduction in calcium stone formation after J-pouch.

Electronic Resource

1432-0800

Springer Online Journal Archives 1860-2000

Energy, Environment Protection, Nuclear Power Engineering

Medicine

Electronic Resource

0040-6090

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Physics

Electronic Resource

1573-0581

Springer Online Journal Archives 1860-2000

Geosciences

Physics

Abstract An inexpensive Pull-Up Shallow Water Seismometer (PUSS) has been designed and built to conduct long range seismic refraction experiments in the North Sea and the continental shelf around Britain, with the particular goal of studying the crustal and lithospheric structure under the epeirogenic basin of the North Sea. Signals from a gimbal-mounted 3-component geophone and a hydrophone are frequency modulated and mixed with clock and flutter correction signals before being recorded on a standard speed cassette tape recorder, with one hour of recording time. A 100 hour programmable timer allows the interval between the time of reset of the clock and each shot window of optional 5 or 10 min duration, to be preselected. The PUSS is launched and recovered using a pull-up technique originally developed for current meters. The replay system is also described. In May 1976 sea trials of 5 PUSSes were conducted along a 200 km refraction line in the North Sea. The encouraging performance of the equipment resulted in the decision to build a further 10 units and to proceed with a 400 km refraction line planned for the summer of 1977.

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] CHRISTIE AND SCLATER REPLY- We thank Smythe et al for providing the opportunity to elaborate on the extensional model for basin formation1. First, it cannot be denied that extension has taken place in the North Sea, and the strong temporal correlations between North Atlantic and North Sea ...

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] Seeds of the two species were collected from a permanent grassland site near Bristol. Soil was collected from a neighbouring field where both species also occur. The soil was mixed and placed in pots 13 cm in diameter; it was not sterilised, nor was fertiliser added. Seeds were germinated in ...

Electronic Resource

1573-5036

Lolium perenne L ; 15N dilution ; nitrogen transfer ; roots Trifolium repens L.

Springer Online Journal Archives 1860-2000

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Abstract The apparent transfer of N from clover to associated grass was evaluated over a four year period both on the basis of harvested herbage and by taking account of changes in N in stubble and root (to 10 cm depth) in swards with perennial ryegrass and three different white clover cultivars differing in leaf size. The large leaved Aran transferred 15% of its nitrogen while Huia transferred 24% and the small leaved Kent Wild White transferred 34%. When changes in stubble and root N were taken into account the percentage of N transferred was calculated to be 5% less than in harvested herbage only, as the small leaved types had proportionately more N in the roots and stolons, but the large leaved type was probably more competitive towards the grass. Loss of N from clover roots from July to October was compared to that from grass roots in a grass/white clover sward continuously stocked with steers using a method which incorporated tissue turnover and 15N dilution techniques. Less than 1 mg N m-2 d-1 was lost from the grass roots. In contrast 8 mg m-2 d-1 were estimated to be lost from clover roots while 12 mg N m-2 d-1 were assimilated. It is concluded that clover cultivar and competitive ability on grass have to be taken into account together with the relationship between N turnover in roots and N available for grass growth when modelling N transfer in grass/clover associations.

Electronic Resource

1573-689X

disaster management ; transportation of patients ; computer simulation

Springer Online Journal Archives 1860-2000

Medicine

Abstract The characteristics of disaster management are outlined. Planning for the efficient management of a disaster is described. The level of preparedness for disasters can be increased using simulation models in conjunction with drills. With the simulation model, “what-if” analyses are performed to predict the consequences of conceivable scenarios. Emergency medical service personnel will find such computer simulation models a useful supplement to their standard training.

Electronic Resource