bluuebunny/crossref_metadata_2025 huggingface dataset:
Long‐term effects of land clearing methods, tillage systems and cropping systems on surface soil properties of a tropical Alfisol in S.W. Nigeria
Authors: Hulugalle N.R.
Published: February 2007

Abstract. The long‐term effects of land clearing methods (manual, shear blade, tree‐pusher/root‐rake combination, traditional), tillage systems (disc ploughing, mechanized no‐tillage, traditional) and cropping systems (annual cropping, alley cropping, graxed pasture) on surface soil physical and chemical properties were evaluated on an Alfisol in south‐western Nigeria ten years after land clearing. Long‐term soil physical degradation was greatest after mechanized land clearing or tillage systems. The erosion resulting from soil compaction with mechanized land management systems resulted in exposure of subsoil. Cropping system had no significant effect on soil physical properties. Alley cropping decreased exchangeable calcium and pH, and increased total acidity mainly through the greater demand for calcium by the hedgerow species. Grazed pasture depleted exchangeable potassium because it was taken up by the grass and exported from the site by the cattle following consumption of the grass.
A soil‐diagnostic key to manage saline and waterlogged catchments in the Mt Lofty Ranges, South Australia
Authors: Fitzpatrick R.W. , Cox J.W. , Fritsch E. , Hollingsworth I.D.
Published: February 2007

Abstract. Dryland salinity in the Mt Lofty Ranges, South Australia has developed as a result of native vegetation being replaced with pastures that use less water. Groundwaters have risen and mobilized ions (sodium, chloride, sulphate and iron) stored within deeply weathered micaceous sandstones and schists. Salinity resulting from sodium chloride is common in agricultural catchments around Australia, but saline sulphidic soils (with sulphate and iron) have only been studied in South Australia. Salinity is also associated with waterlogging and secondary sodicity. The amelioration of dryland salinity and waterlogging involves management of whole catchments, not just the area that is currently saline. It is imperative that all processes operating in saline catchments and their interactions are clearly understood.

Salinity, waterlogging, sodicity, sulphidization and water erosion were studied in four saline sub‐catchments in the Mt Lofty Ranges. Grey (bleached) and yellow mottles (iron depletions) or black and red stains (iron concentrations) develop under certain conditions of water saturation, salinization, sulphidization, sodification and water erosion in surface and subsurface horizons. The amounts of these diagnostic features were used to develop a farm planning key for managing saline catchments in the Mt Lofty Ranges. Using soil diagnostic features, soil‐water processes in saline catchments are easily identified by farmers and land managers. Management options (e.g. fencing, tree planting and drainage) are then targeted to specific soils and can be easily incorporated by agricultural advisers into farm management plans. We recommend that soil diagnostic features which help predict the onset of land degradation be used in the production of land capability maps for farm planning purposes.
Testing a low‐quality urban compost as a fertilizer for arable farming
Authors: Murillo J.M. , López R. , Cabrera E , Martín‐Olmedo P.
Published: February 2007

Abstract. A coarse urban compost, low in organic matter but mature, was tested for agricultural use. The response of Tewera ryegrass to this compost (applied at 12 and 48 t/ha) was evaluated in a field trial over two years. For a satisfactory yield the larger dose was necessary. This dose also gave greater values for the apparent recovery of N in both years. However, the N concentration in ryegrass was always below the sufficiency ranges proposed for N. The values of the potentially mineralizable N of the compost showed that the applied N at the greater rate of compost application was not sufficient to cover crop removal of N. In contrast, concentrations of P, S, K, Mn and Zn were within their corresponding sufficiency ranges. The dose of 48 t/ha did not increase Cu, Ni, Pb and Cd concentrations in the ryegrass.
Economic land evaluation: why and how
Authors: Rossiter D.G.
Published: February 2007

Abstract. Economic land evaluation is a method for predicting the micro‐economic value of implementing a given land‐use system on a given land area. This is a more useful prediction of land performance than a purely physical evaluation, since many land‐use decisions are made on the basis of economic value. Measures of economic suitability include the gross margin, net present value, internal rate of return, benefit:cost ratio, and utility functions based on these. The economic value of the in‐situ resource quality of a land area may be inferred directly from land characteristics or from Land Qualities which, when less than optimum, result in decreased yields or increased costs. The economic value of geographic land characteristics may be determined by spatial analysis. Single or multi‐criteria economic optimization and risk analysis can extend the economic land evaluation from a natural resource or management unit to a production or planning unit. Computerized tools may be used to assist in economic land evaluation.
Traffic and tillage effects on soil conditions and crop growth on a swelling clay soil
Authors: Chamen W.C.T. , Longstaff D.J.
Published: February 2007

Abstract.Trafficked and non‐trafficked (12 m gantry) crop production systems, which had been maintained on an Evesham series 60% clay soil since 1986, were used again in 1993 during the cultivation and sowing of winter wheat. After a one year set‐aside break, mouldboard ploughing, tine cultivation and rotary digging were compared. Measurements were made of tillage energy, soil tilth, cone penetration resistance, biological activity and crop performance, and on specific plots, soil density, seedbed tilth and water release characteristics.

Despite the one year's set‐aside break, the effect of the previously applied traffic treatments remained and resulted in a smaller specific plough resistance and tillage energy on the non‐trafficked soil. Tine cultivator draught however was greater on the non‐trafficked compared with the trafficked plots. The specific energy required for rotary digging on non‐trafficked soil was similar to that required during the ploughing of similar plots.

A measure of indefinite biotic activity indicated that this was apparently greater on the non‐traffficked soil, while soil density was decreased by up to 18% in these conditions compared with the trafficked land. Average cone resistance over the depth range 0 to 0.5 m was 1.51 MPa on the trafficked, compared with 1.24 MPa on the non‐trafficked soil. Cone resistance also tended to be greater after tine cultivation compared with that after ploughing. Water release curves were interpreted as showing more macropores within the topsoil of the non‐trafficked compared with the trafficked plots. Tine cultivation on trafficked soil had more smaller pores than mouldboard plough cultivation. Winter wheat yield was increased by 25% (from 8 to 10 t/ha) on non‐trafficked compared with trafficked soil.
Increase in soluble phosphorus transported in drainflow from a grassland catchment in response to soil phosphorus accumulation
Authors: Smith R.V. , Lennox S.D. , Jordan C. , Foy R.H. , McHale E.
Published: February 2007

Abstract.Because of the observed variability in soil available P (Olsen) contents, phosphorus budgets were used to predict changes in the soil P status of an intensively managed 6 ha grassland catchment in Northern Ireland. The P accumulation rate of approximately 24 kg/ha/y suggested an increase of soil available P (Olsen) of 1.0 mg P/kg/y. Soluble reactive phosphorus concentrations in drainflow measured on a daily basis for a two year period (January 1981 — December 1982) were compared with the two year period January 1990 — December 1991. The median concentration had increased by 10.0 μg P/1 in 1990/91 compared with 1981/82. This difference was only apparent in mean concentrations for the two time periods, after data associated with high flow events, which were more frequent in 1981/82, were excluded from the comparison. This rate of increase of 1.1 μg P/1/y, which was interpreted as reflecting an increase in soluble reactive phosphorus concentration in soil solution, is comparable to the increase in background soluble reactive phosphorus of 1.5 ± 0.54 μg P/1/y which was reported recently over a 17 year period from diffuse sources in the much larger (4400 km2) Northern Ireland catchment of Lough Neagh.
How good is a reconnaissance soil map for agronomic purposes?
Authors: Oberthür T. , Dobermann A. , Neue H.U.
Published: February 2007

Abstract. Information about the soil fertility status in irrigated ricelands at regional scales (1:50 000–1:250 000) is commonly not contained in classical soil maps. To assess the agronomic suitability of two different reconnaissance soil maps, we conducted a detailed soil survey in the Nueva Ecija province, Philippines. Soil samples were collected from 384 farmers' fields, and soil properties were measured for topsoil and subsoil samples. For most soil properties, a soil map made in 1940 (1:125 000) had within‐map unit variances that were smaller than the total variance, whereas a new soil map of 1992 (1:50 000) did not significantly reduce the within‐class variance. In both soil maps, classification into mapping units accounted for 0–40% of the variance of 14 agronomically important soil properties and large within‐map unit variabilities were found. Underlying strategies of classical soil survey supported the partition of variance for relatively stable soil properties, such as soil texture, CEC, and organic matter. If reconnaissance soil maps are used in quantitative land evaluation studies, existing maps require upgrading by adding quantitative information about relevant soil properties and their within‐map unit variability The sampling demand for upgrading a reconnaissance soil map was large, but pedotransfer functions can be used as cost‐saving tools. Measures of soil nutrient status were highly variable within all mapping units and differences among farmers were much greater than the differences between soil types. Therefore, nutrient management in the study region should be based on individual field or farm recommendations rather than on soil‐map based recommendations.
Influence of exchangeable potassium on soil erodibility
Authors: Auerswald K. , Kainz M. , Angermüller S. , Steindl H.
Published: February 2007

Abstract. Regular application of slurry manure in large quantities is thought to degrade soil structure and increase erodibility. One hypothesis links this to the large input of potassium which increases the exchangeable potassium percentage (EPP) and, thereby, dispersion. The effect of EPP on erodibility was quantified in three experiments. In the laboratory, eleven rainfall experiments were conducted using a silty topsoil from a typic Hapludalf which was fertilized to EPPs of 4 to 18%. Field rainfall experiments on 22 Inceptisols and Alfisols were used to examine whether the long‐term application of monovalent cations (Na+, K+ and NH4+) with slurry manure had changed soil properties, especially erodibility. In addition, erodibilities of 32 soils determined with natural and simulated rains were taken from literature. The experiments on these 65 soils together covered a wide range of soils, slopes and rainfalls. Dispersion by a large percentage of highly hydrated ions (K+, Na+) reduced the infiltration rate faster, caused runoff up to 5 min earlier, and increased sediment concentrations by 15g/l compared to low EPP soils. These changes increased soil erodibility of the Universal Soil Loss Equation (USLE) by 0.021 t × h/N × ha (where N = Newtons) for each 1% increase in EPP + ESP (exchangeable sodium percentage). The ESP contributed little to this increase as ESP was less than 1/10 of EPP in the experiments.

Fields with long‐term manure application had similar chemical, physical and microbiological soil properties as fields without slurry manure except for slightly greater pH (+ 0.6) and P (+ 17 mg/kg) values. We conclude that, as long as the potassium input and output are balanced, the long‐term use of slurry manure does not increase erodibility.
A model for estimating soil moisture changes as an aid to irrigation scheduling and crop water‐use studies: I. Operational details and description
Authors: Bailey R.J. , Spackman E.
Published: February 2007

Abstract. A model was developed to predict evapotranspiration and soil moisture changes, which could be used either for scheduling irrigation or crop water‐use studies. The general form of the model is reported here, and its validation for sugarbeet and potatoes is described in a subsequent paper. The soil characteristics required are depth of topsoil, texture or available water capacity of topsoil and subsoil, and whether a significant slope exists. The plant characteristics required are species and planting date. Meteorological data used to calculate potential evapotranspiration are obtained from the Meteorological Office synoptic network, but local rainfall data are preferred.

The model estimates potential evapotranspiration of a reference crop, and uses this to model canopy and root development for all crops at each location. Available options allow for observed data on canopy or root development to be incorporated into the simulations. Estimates of potential evapotranspiration for each crop are then adjusted to allow for the effects of water stress, taking soil characteristics, root depth and evapotranspiration demand into account.

The model enables growers to reduce the risks of under‐ or over‐watering their crops and has proved successful in irrigation management.
Thin section studies of Calluna heathland soils subject to prescribed burning
Authors: Mallik A.U. , FitzPatrick E.A.
Published: February 2007

Abstract. Soil microstructures and biological activity were studied in thin sections of Culluna heathland soils subject to periodic burning. Freely drained Brown Podzolic soils from a species‐rich heath at Dinnet Muir, Aberdeenshire, Scotland were compared with shallow Humo‐ferric Podzols with a thick humus layer (5–10 cm) supporting a species‐poor heath at Balmenach, Aberdeenshire.

Structures with greater porosity occurred in all Dinnet soils and the most recently burned Balmenach soil. Burning led to an increase in soil porosity which gradually disappeared after a period of 2–3 years. Soils of the recently burned site had more enchytraeid worms than those burned ten years previously. Most of the Dinnet soil samples were dominated by extremely fine granular structure which could have been produced by flocculation of well decomposed organic matter or by enchytraeid worms. In recently burned sites the increase in soil macro‐ and microbial activities may lead to the formation of composite structures.

Regular burning every 10–15 years has been the land management practice in Scottish heathlands to ensure the production of fresh browse of nutritious heather shoots for herbivores. The near‐ground microclimate and regeneration mechanisms of heathland plants are well adjusted to the periodic disturbance by fire. We found that the gradual decrease in surface soil porosity over time can be restored by prescribed burning. Soil structure and the distribution and continuity of pores in the soil profile directly affect soil water movement and retention. These factors have important ecological implications for post‐fire vegetation recovery.
Residue management for reducing evaporation in relation to soil type and evaporativity1
Authors: Prihar S.S. , Jalota S.K. , Steiner J.L.
Published: February 2007

Abstract. Usual residue‐management options are to remove the residue, use it as mulch with or without undercutting or to incorporate it into the soil. While the role of surface mulch in evaporation has been widely studied, the information on the effect on evaporation of mulch with undercutting or residue incorporated into soil, particularly in relation to soil type and evaporativity (Eo) is lacking. We studied the effect of wheat straw used in various ways on the course of evaporation loss from soil columns with three soils at Ludhiana, India and one soil at Bushland, Texas, USA, under two Eo's Energy‐limited evaporation rates under mulch (Eom) followed the soil‐specific relation Eom/Eo= a e(bRes+cEo), where Res is residue rate t/ha and a, b and c are constants; Eo, is expressed in mm/d. In an effort to model the total evaporation (CE) during the energy‐limited stage ‘U’ was obtained from appropriate CE versus time curves and (CE‐U) was regressed over (t ‐ ti)0.5 to obtain the slope ‘α’ (Ritchie 1972) for the soil‐limited evaporation stage. The observed ‘U’ was independent of mulch rate and Eo but was strongly affected by soil type, Values of ‘α’ decreased with increase in mulch rate and decrease in Eo and coarseness of soil.

The otherwise short lived benefit of evaporation reduction with mulch per se, which peaked after a few days was maintained when residue was mixed with soil at the stage when evaporation reduction reached a maximum; this benefit continued for several weeks. Cumulative evaporation values computed from ‘U’ and ‘α’ agreed closely with the observed values under straw mulch for loamy sand and clay loam soils and for ‘undercut’ and ‘residue mixed’ treatments on all soils regardless of Eo, and for all situations under small Eo. However, for sandy loam and silt loam soils under Eo of 10 mm/d, the modified square root of the time function of Jalota et al. (1988) gave a better fit.
The estimation of losses of potassium and magnesium from chalky soils in southern England: laboratory studies
Authors: Heming S. D. , Rowell D. L.
Published: February 2007

Abstract. Ten chalk topsoils (0‐25 cm) were repacked into columns in the laboratory. After leaching similar to one year's throughflow in the field, loss of K was equivalent to between 9 and 74kg K/ha. This represented between 3 and 30% of the initial exchangeable K with which loss was poorly correlated. Loss was dependant on the soil solution concentration and was inversely proportional to potassium buffer power.

The loss of magnesium in the same columns was between 10 and 22 kg Mg/ha (6‐21% of the initial exchangeable Mg). Magnesium loss was poorly correlated with exchangeable Mg.

When KCl fertilizer was incorporated into the soils, the increase in leaching of potassium was 1–35% of the K addition. Application to the top of the column resulted in less leaching than when the K was incorporated. Leaching of magnesium was increased by up to 5 kg Mg/ha.

Potassium leaching may be delayed by the underlying A/C horizon but pure chalk, with an extremely low buffer power for K, has little ability to retain K. Extremely calcareous topsoils were the most leaky although in practice it is the organic chalk soils on which it is most difficult to attain adequate K levels. On all chalk soils, maintenance of a high K level with K fertilizer is likely to cause unnecessary long‐term leaching losses. Annual, rather than biennial, fertilizer applications are to be preferred.
Soil physical properties of afforested and arable land
Authors: Messing I. , Alriksson A. , Johansson W.
Published: February 2007

Abstract. The effects of tree crops on the soil physical properties of former agricultural land were compared with those of ley in a rotation with cereals on adjacent sites. Five sites in southern Sweden were investigated focussing on soil water retention characteristics, dry bulk density, macroporosity and saturated hydraulic conductivity. Three of the sites were on light textured soils and two on clay soils. The tree crops were 30 to 35‐year‐old hybrid aspen, Populus deltoides, and silver birch, Betula pendula, and the ley crops were one to five years old.

The light‐textured soils under tree crops showed bimodal pore size distributions in the macropore region, whereas under ley crops they showed unimodal distributions. Dry bulk densities were generally smaller and the macroporosities larger under tree crops compared with leyicereal crops. Saturated hydraulic conductivities tended to be larger under tree crops. Slopes of the linear regression lines between saturated hydraulic conductivity and each of the parameters dry bulk density, porosity and macroporosity were steeper in the soil under agricultural crops than under tree crops.

Observed differences in physical properties were considered to be an effect of land use, which had brought about changes in aggregate stability, pore size distribution and pore continuity.
Nitrous oxide emissions from grazed grassland
Authors: Oenema O. , Velthof G. L. , Yamulki S. , Jarvis S. C.
Published: February 2007

Abstract. Grazing animals on managed pastures and rangelands have been identified recently as significant contributors to the global N2O budget. This paper summarizes relevant literature data on N2O emissions from dung, urine and grazed grassland, and provides an estimate of the contribution of grazing animals to the global N2O budget.

The effects of grazing animals on N2O emission are brought about by the concentration of herbage N in urine and dung patches, and by the compaction of the soil due to treading and trampling. The limited amount of experimental data indicates that 0.1 to 0.7% of the N in dung and 0.1 to 3.8% of the N in urine is emitted to the atmosphere as N2O. There are no pertinent data about the effects of compaction by treading cattle on N2O emission yet. Integral effects of grazing animals have been obtained by comparing grazed pastures with mown‐only grassland. Grazing derived emissions, expressed as per cent of the amount of N excreted by grazing animals in dung and urine, range from 0.2 to 9.9%, with an overall mean of 2%. Using this emission factor and data statistics from FAO for numbers of animals, the global contribution of grazing animals was estimated at 1.55 Tg N2O‐N per year. This is slightly more than 10% of the global budget.
Measured and simulated availability and leaching of nitrogen associated with frequent use of catch crops
Authors: Aronsson H. , Torstensson G.
Published: February 2007

Abstract. Results are presented from three years (1992‐1995) of a field leaching experiment on a sandy soil in south‐west Sweden. Plots of spring cereals, either with or without an undersown perennial ryegrass catch crop, were compared for nitrogen leaching and nitrogen status in soil. Both treatments were ploughed in spring, and other tillage regimes were also identical. Measurements of nitrogen leaching from drains, nitrogen uptake in crops and mineral nitrogen in the soil were made. Two coupled, simulation models, which describe water flow and nitrogen transformations and transport in soil, were used to interpret data and to calculate the nitrogen budget and nitrogen mineralization in the soil.

Nitrogen leaching was 40 50% less in the catch crop treatment compared with the control during years when the establishment of the catch crop succeeded. In the third year of the experiment nitrogen leaching was actually greater in the catch crop treatment (7 kg N/ha). This increase was caused by a poorly established catch crop coinciding with enhanced mineralization of previous catch crop residues. There was no simulated change in soil organic nitrogen in either of the treatments. Simulations showed increased nitrogen mineralization during April‐July after incorporation of plant material in spring, especially in the catch crop treatment. However, the increased nitrogen mineralization probably occurred too late for the released nitrogen to be fully available to the main crop.
Control of nitrate leaching from a Nitrate Vulnerable Zone using paper mill waste
Authors: Vinten A. J. A. , Davies R. , Castle K. , Baggs E. M.
Published: February 2007

Abstract. The effects on nitrate leaching of incorporation of paper mill waste at three cultivation depths in fields previously cropped to iceberg lettuce and calabrese are reported. In the lettuce experiment, incorporation of 40 t DM paper mill waste/ha resulted in a decrease in N leaching (measured with suction cups) from 177 to 94 kg/ha (S.E.d= 23). Deep ploughing with and without paper waste increased N leaching from 105 kg/ha (normal ploughing or surface incorporation) to 172 kg/ha (S. E. d= 27). Measurements of nitrate leaching using deep soil cores showed a less clear cut effect. Nitrous oxide (N2O) emissions were very high immediately after paper waste was ploughed in to a depth of 35 cm. Non–significant increases in biomass N content were measured in the spring following paper waste application. There was no significant reduction in plant N uptake in subsequent crops. Removal of above–ground crop residues did not have a significant effect on nitrate leaching or N2O losses. In the calabrese experiment, application of 40 t DM paper mill waste/ha followed by summer cropping with iceberg lettuce caused a decrease in N leaching (measured using deep soil cores) from 227 to 152 kg/ha (S. E.d= 22, mean of all cultivation treatments).
Influence of farmyard manure, inorganic fertilizers and weed control practices on some soil physical properties in a long‐term experiment
Authors: Benbi D. K. , Biswas C. R. , Bawa S.S. , Kumar K.
Published: February 2007

Abstract. In a long‐term experiment, soil physical properties were studied after 20 annual cycles of maize‐wheat‐fodder cowpea cropping with annual application of inorganic fertilizers and farmyard manure (FYM). Weeds were controlled by hand or by the use of herbicides. The hand weeding treatment resulted in a lowering of the bulk density of the surface layer (0‐15 cm) and a significant increase in the subsurface (15–30 cm) density. Application of FYM significantly increased the soil organic carbon (OC), infiltration rate, water retention, aggregation and aggregate stability in water. Application of inorganic fertilizers had small but statistically significant effect in increasing soil OC.
Reactions of phosphorus with sediments in fresh and marine waters
Authors: House W. A. , Jickells T. D. , Edwards A. C. , Praska K. E. , Denison F. H.
Published: February 2007

Abstract. The interactions of P with soils and sediments are examined in the context of transport processes from land, through rivers to estuaries and coastal waters. In soil erosion, selective size fractionation and preferential sorption to finer solids is crucial in the transport of P to water courses. Problems in quantifying the sorption affinity and equilibrium phosphate concentration (EPC) of mixtures of different soils and sediments are identified. Riverine transport of P by suspended solids is usually very important and examples of the changes in the amount and composition of particulate P (PP) concentration during storm events are discussed. Increased P content of solids during the first autumn storms, probably reflect the resuspension of accumulated stream bed‐deposits. The fate of P in estuaries and their importance as possible long‐term sinks of P are discussed. The relatively high concentrations of dissolved P associated with riverine inputs are to some extent buffered by the relatively high concentrations of suspended sediments resulting from tidal flows. Phosphorus may be released during transport to the sea due to decreases in the EPC, increases in salinity and release from bottom sediments as a result of low oxygen conditions.
Phosphorus budgets for two contrasting grassland farming systems in the UK
Authors: Haygarth P. M. , Chapman P. J. , Jarvis S. C. , Smith R. V.
Published: February 2007

Abstract. Phosphorus budgets have been compiled for two contrasting grassland farming systems in the UK; intensive dairy farming and extensive hill sheep production. Balance sheets of inputs, recycling of P through the soil–plant–animal pathway and outputs are presented to determine the potential rate of P accumulation in the two systems. A typical 57 ha intensive dairy farm with 129 lactating cows imports 2.48t P via fertilizer, bedding and concentrates, plus a small amount from the atmosphere, of which 0.98t are exported in milk, calves and transfer from soil to the aquatic environment. Therefore 1.5t of P are retained within the farm each year, which equates to an accumulation rate of 26 kg/ha in the plant‐soil system. This surplus occurs despite a fertilizer input of only 16 kg/ha. However, a large proportion of P, equivalent to 27 kg/ha, is imported in feed concentrates.

For the typical 841 ha hill sheep farm supporting 694 Blackface ewes, P inputs and outputs are 0.66 and 0.42 t/yr, respectively. Therefore, approximately 0.24t P are retained within the farm, which is equivalent to an accumulation rate of 0.28 kg/ha per yr. In comparison to the small annual inputs and outputs of P on the hill farm, much P, 2.48t, is recycled through the plant‐soil and plant‐animal‐soil pathways on the hill sheep farm. For both farming systems there is a net input of P, although the rate of accumulation is ten times greater for the dairy farm where the annual retention of P represents 60% of the total P inputs, compared with 36% on the hill sheep farm.
Walking and Non‐HDL‐C in Adults: A Meta‐Analysis of Randomized Controlled Trials
Authors: Kelley George A. , Kelley Kristi S. , Tran Zung Vu
Published: February 2007

An elevated level of non‐high‐density lipoprotein cholesterol (non‐HDL‐C) is a major risk factor for cardiovascular disease. The purpose of this study was to use the meta‐analytic approach to examine the effects of walking on non‐HDL‐C in adults. Twenty‐two randomized controlled trials representing 30 outcomes from 948 subjects (573 exercise, 375 control) met our inclusion criteria. Across all designs and categories, random effects modeling resulted in a significantly greater decrease in the walking group when compared with the control group of approximately 4% for non‐HDL‐C (± standard error of the mean, −5.6±1.8 mg/dL, 95% confidence interval, −8.8 to −2.4 mg/dL). Meta‐regression showed a statistically significant association between changes in non‐HDL‐C and the year of publication, with greater reductions associated with more recent publication year (R2=0.23, p=0.005). The results of this meta‐analytic review suggest that walking reduces non‐HDL‐C in adult humans.
Heart Rate Recovery After Exercise and Endothelial Function—Two Important Factors to Predict Cardiovascular Events
Authors: Huang Po‐Hsun , Leu Hsin‐Bang , Chen Jaw‐Wen , Lin Shing‐Jong
Published: February 2007

An attenuated heart rate recovery immediately after exercise, thought to be a marker of reduced parasympathetic activity, has been demonstrated to be an independent predictor of all‐cause mortality in several large‐scale studies; however, the mechanisms by which impaired heart rate recovery confers an increased risk of death are not clear. From clinical observation, vagal reactivation was thought to be the major determinant of the decrease in heart rate during the first 30 seconds of recovery, independent of age and the intensity of exercise; however, patients with attenuated heart rate recovery were also shown to have lower exercise workload, shorter exercise duration, lower numbers achieving 90% target heart rate, and even impaired endothelial function. This review focuses on the roles of heart rate recovery and endothelial function in predicting future mortality and their interaction.
Systemic Inflammation, Blood Pressure, and Stroke Outcome
Authors: Napoli Mario Di , Papa Francesco
Published: February 2007

Hypertension is the most important modifiable risk factor for ischemic stroke, and antihypertensive treatment is of paramount importance to reduce the incidence of stroke mortality and morbidity. The significance and best management of hypertension during the first hours after stroke onset, however, are still matters of debate. Cerebral ischemia results in a complex inflammatory cascade; inflammatory mechanisms are also important participants in the pathophysiology of hypertension. There has been a convergence of evidence that is important to consider in managing systemic blood pressure after stroke to ensure an optimal outcome. The identification of useful markers will allow progress in our ability to treat blood pressure in the acute phase of a stroke. The determination of levels of C‐reactive protein, an acute‐phase inflammation marker, may help to guide our approach in the management of blood pressure in acute ischemic stroke. Whether this target will be useful in the development of risk prediction strategies or therapies for the treatment of stroke in humans is far from clear.
The Metabolic Syndrome and Its Relationship to Hypertensive Target Organ Damage
Authors: Mulé Giuseppe , Cerasola Giovanni
Published: February 2007

High blood pressure is often associated with various metabolic abnormalities, including abdominal obesity, dyslipidemia, elevated plasma glucose, and insulin resistance, which are the main features of the metabolic syndrome. The metabolic syndrome is extremely common worldwide. This high prevalence is of considerable concern because several studies suggest that the metabolic syndrome carries an increased risk for cardiovascular events. Several lines of evidence seem to indicate that the metabolic syndrome is associated with an increased prevalence of preclinical cardiovascular and renal changes, such as left ventricular hypertrophy, microalbuminuria, impaired aortic elasticity, and early carotid atherosclerosis, most of which are recognized as significant independent predictors of adverse cardiovascular outcomes. It is conceivable that these data may partly explain the high rates of cardiovascular morbidity and mortality that are observed in patients with the metabolic syndrome.
Hypertension in Minority Populations
Authors: Ferdinand Keith C.
Published: February 2007

The US population, by percentage, shows a trend toward increased proportions of citizens identified as minorities. Whereas in 2000, according to the US Census Bureau, 71.4% of the population was self‐identified as white; this group is expected to decrease to 61.9% by 2025. The proportion of blacks and African Americans from 2000 vs. 2025 is expected to increase from 12.2% to 12.9%. Also, in the smaller population of American‐Indian, Eskimo, and Aleutian natives, growth is projected from 0.7% to 0.8%. Asians and Pacific Islanders as a category will become a larger proportion, from 3.9% to 6.2%. The largest increase in proportion will be seen in those identified as Hispanic (of any race), from 11.8% in 2002 to 18.2% in 2025.
Metoprolol Succinate, a Selective β‐Adrenergic Blocker, Has No Effect on Insulin Sensitivity
Authors: Falkner Bonita , Francos George , Kushner Harvey
Published: February 2007

Insulin resistance is a risk factor for cardiovascular disease. Therapies to lower blood pressure should not decrease insulin sensitivity. Some β‐adrenergic blocking agents can have an adverse effect on insulin sensitivity. This study examined the effect of extendedrelease metoprolol succinate on insulin sensitivity. Nondiabetics with hypertension (N=30) were started on (or changed to) hydrochlorothiazide (HCTZ) 12.5 mg daily for 14 days. Patients with blood pressure >140/90 mm Hg while taking HCTZ alone underwent an insulin clamp procedure to quantify insulin sensitivity. Metoprolol succinate treatment was begun at 50 mg daily and titrated to a dose that lowered blood pressure to <140/90 mm Hg. Following 12 weeks of metoprolol succinate plus HCTZ therapy, the insulin clamp procedure was repeated. On metoprolol succinate plus HCTZ treatment, there were no significant changes in insulin clamp measures of insulin sensitivity. Plasma cholesterol and low‐density lipoprotein cholesterol decreased significantly on metoprolol succinate plus HCTZ. When β‐blocker therapy is considered, metoprolol succinate can be used to treat hypertension without adverse metabolic effects.
Endothelial Vascular Function in Hypertensive Patients After Renin—Angiotensin System Blockad
Authors: Souza‐Barbosa Leon´ Adriana , Ferreira‐Melo S´lvia E. , Ubaid‐Girioli Samira , Nogueira Eduardo Arantes , Yugar‐Toledo Juan Carlos , Moreno Heitor
Published: February 2007

It is unclear whether single and combined pharmacologic inhibition of the renin‐angiotensin‐aldosterone system have similar effects on endothelial function and blood pressure (BP). The authors evaluated 63 hypertensive patients divided into 4 groups (hydrochlorothiazide 25 mg/d; irbesartan [IRBE] 150 mg/d; quinapril [QUIN] 20 mg/d; or IRBE 150 mg/d + QUIN 20 mg/d) and 25 healthy normotensive subjects (normal) followed for 12 weeks. Endothelium‐dependent dysfunction measured as flow‐mediated dilation at Weeks 0 and 12 were: normal, 11.5%±2.4% vs 13.5%±2.0%; hydrochlorothiazide, 7.3%±2.0% vs 12.8%±3.1%; QUIN, 7.2%±2.8% vs 13.2%±2.1%; IRBE, 7.1%±2.8% vs 13.0%±2.9%; and IRBE + QUIN, 7.5%±1.9% vs 12.8%±3.0%. Nitroglycerin‐mediated responses were: normal, 26.0%±1.9% vs 24.0%±2.5%; hydrochlorothiazide, 17.0%±2.2% vs 18.3%±2.6%; QUIN, 17.8%±3.2% vs 23.4%±3.0%; IRBE, 16.8%±3.6% vs 24.7%±2.0%; and IRBE + QUIN, 17.3%±3.0% vs 25.1%±2.5%. Antihypertensive therapy restored BP to normal and improved the endothelium‐dependent and ‐independent dysfunction after renin‐angiotensin‐aldosterone system blockade. In a further finding, the combined effect of angiotensin‐converting enzyme inhibition and angiotensin II type 1 receptor blockade was not superior to the action of either of these treatments separately.
A Randomized, Double‐Blind Trial Comparing the Effects of Amlodipine Besylate/Benazepril HCl vs Amlodipine on Endothelial Function and Blood Pressure
Authors: Mohler Emile R. , Herrington David , Ouyang Pamela , Mangano Charles , Ritter Susan , Davis Pamela , Purkayastha Das , Gatlin Marjorie , Vogel Robert A.
Published: February 2007

Evidence suggests that renin‐angiotensin‐aldosterone system inhibition ameliorates endothelial dysfunction. The authors examined the effect of amlodipine besylate/benazepril HCl combination treatment compared with amlodipine besylate monotherapy in modulating endothelial dysfunction. This multicenter, double‐blind, 12‐week study randomized 70 hypertensive subjects with at least one other endothelial dysfunction risk factor to amlodipine besylate/benazepril HCl (5/20 mg/d force‐titrated to 5/40 mg/d) or amlodipine besylate monotherapy (5 mg/d force‐titrated to 10 mg/d). Both the combination and monotherapy produced significant median increases from baseline in percentage flow‐mediated vasodilation (2.0% and 1.2%, respectively) and percentage change in percent flow‐mediated vasodilation (25% and 16%, respectively). These improvements were numerically larger with combination treatment, but between‐group differences did not achieve statistical significance. Reductions in systolic and diastolic blood pressure were significantly greater (P=.0452/P=.0297) with combination treatment (−18.6/−12.3 mm Hg) than with monotherapy (−14.8/−9.1 mm Hg). A highly positive correlation between change in systolic blood pressure and change in percent of flow‐mediated vasodilation was demonstrated only for combination treatment.
Familial Aggregation of Insulin Resistance and Cardiovascular Risk Factors in Hypertension
Authors: Raji Annaswamy , Williams Jonathan S. , Hopkins Paul N. , Simonson Donald C. , Williams Gordon H.
Published: February 2007

The authors assessed the familial aggregation of cardiometabolic abnormalities (elevated homeostasis model assessment [HOMA], triglycerides [TG], and low‐density lipoprotein [LDL] and reduced high‐density lipoprotein [HDL]) among hypertensive siblings (N=287 from 138 families). Evidence for familial aggregation required sibling‐pair concordance of outcome variables dichotomized according to predefined values (concordance for highest‐quartile HOMA [>3.3], TG [>170 mg/dL], and LDL [>138 mg/dL] and lowest‐quartile HOMA for HDL [<32 mg/dL]). Hypertensive individuals with insulin resistance (high‐quartile HOMA) had higher TG and lower HDL and LDL levels compared with insulinsensitive hypertensives. High‐quartile HOMA, TG, and LDL aggregated in hypertensive families, and TG plus HOMA coaggregated. HDL did not show aggregation. In a multivariate logistic regression, the only significant predictor of an individual's HOMA status was a sibling's HOMA status in a model including age, sex race, and body mass index (odds ratio=9.12; 95% confidence interval, 3.64–23.14; P<.001). Cardiometabolic variables demonstrate heritability in hypertensive families. Further exploration of common genetic susceptibility loci in hypertension involving these factors is warranted.
In vitro function and phagocytosis of galactosylated platelet concentrates after long‐term refrigeration
Authors: Babic Aleksandar M. , Josefsson Emma C. , Bergmeier Wolfgang , Wagner Denisa D. , Kaufman Richard M. , Silberstein Leslie E. , Stossel Thomas P. , Hartwig John H. , Hoffmeister Karin M.
Published: February 2007

BACKGROUND: Short‐term refrigeration of platelets (PLTs) in the absence of plasma results in their rapid clearance after transfusion. Blocking β‐N‐acetylglucosamine (β‐GlcNAc) residues of glycoprotein Ibα (GPIbα) with galactose prevents binding of refrigerated human and mouse PLTs to macrophages and prolongs the circulation times of refrigerated mouse PLTs. PLT‐associated galactosyltransferase efficiently galactosylates chilled PLTs in the presence of its substrate UDP‐galactose is added to PLT‐rich plasma.

STUDY DESIGN AND METHODS: To characterize the hemostatic function of refrigerated and galactosylated human PLTs processed in the blood bank, PLT aggregation was studied in vitro under static and flow conditions and expression of integrin β3 (CD61), CD62P (P‐selectin), GPIbα (CD42b), annexin V binding, and integrin αIIβ3 activation with flow cytometry. Affinity of macrophages for galactosylated refrigerated PLTs was evaluated with THP‐1 cells, which recognize and phagocytize refrigerated PLTs.

RESULTS: PLTs refrigerated and galactosylated for 14 days 1) maintained their ability to aggregate when exposed to agonists in a standard aggregometry assay, 2) showed less pronounced changes in surface expression of GPIbα compared with room temperature (RT)‐stored PLTs, 3) increased P‐selectin expression, and 4) were poorly phagocytized by differentiated THP‐1 cells in vitro. In addition, it is shown that refrigeration of PLTs does not affect their adhesive properties under in vitro flow conditions.

CONCLUSION: It is shown that refrigerated human PLTs retain in vitro function better than RT PLTs during storage and demonstrate that galactosylation prevents recognition of stored refrigerated PLTs by macrophages in vitro.
Prospective, Multicenter Study of Thrombectomy in Patients with Acute Myocardial Infarction: The X‐Tract AMI Registry
Authors: YOUNG JOHN J. , COX DAVID A. , STUCKEY THOMAS , BABB JOSEPH , TURCO MARK , LANSKY ALEXANDRA J. , MEHRAN ROXANA , STONE GREGG W.
Published: February 2007

Background: Thrombus and soft, friable atheromatous plaque are present in the majority of patients with acute myocardial infarction (AMI), and may result in distal embolization and no reflow during primary angioplasty. Thrombectomy prior to intervention may decrease thromboembolic complications and improve outcomes.

Methods: The X‐TRACT AMI registry was a prospective, multicenter study evaluating the safety and feasibility of the X‐Sizer thrombectomy system prior to primary angioplasty in native coronary arteries and saphenous vein grafts (SVGs) in patients presenting within 24 hours AMI onset.

Results: A total of 216 patients (220 target lesions) with AMI were enrolled at 28 U.S. sites, with approximately 90% of lesions in native coronary arteries and 10% in SVGs. Preprocedural TIMI 0/1 flow was present in 56% of patients, with thrombus in 76%. Glycoprotein IIb/IIIa inhibitors were used in 86% of patients, and bare metal stents were implanted in 94% (mean stent length 26 mm). TIMI‐3 flow was present in 27% of patients at baseline, in 81% after thrombectomy, and in 92% following PCI. Normal myocardial blush grade 3 was present in 6% of patients at baseline, and in 52% postprocedure. At 30 and 360 days, 93.1% and 80.8% of patients were free from major cardiovascular events.

Conclusion: In this broad multicenter experience, use of the X‐Sizer device prior to stent implantation in thrombus containing native coronary arteries and diseased SVGs was feasible and associated with high rates of normalized postprocedural epicardial blood flow and myocardial blush, warranting further study as an adjunct during primary angioplasty.
Explaining Japan's Tortured Course to Surveillance Satellites
Authors: Oros Andrew L.
Published: February 2007

On December 25, 1998 the Japanese government reinterpreted a long‐standing policy prohibiting the use of outer space for military purposes by announcing its intention to develop a network of domestically produced and deployed “information‐gathering” satellites to be utilized primarily by theJapan Defense Agency(JDA) and other national security institutions. This decision is important in its own right—for one, Japan is a major player in the space technology arena—but also because of the precedent it sets for other areas of technology and military policy in Japan today. As many observers have noted, Japan appears to be undergoing a broad reexamination both of its view of the appropriate level of interaction between government bureaucracy and industry and of its military security strategy in the first decade of the twenty‐first century. The case of surveillance satellites links these two areas together, offering broader lessons for the course of Japanese policy in numerous areas in the future.
A Single Mutation in the FGA Locus Responsible for False Homozygosities and Discrepancies Between Commercial Kits in an Unusual Paternity Test Case
Authors: Ricci Ugo , Melean German , Robino Carlo , Genuardi Maurizio
Published: February 2007

ABSTRACT: We report an unusual paternity test case showing multiple peculiarities. Using AmpFlSTR® Profiler Plus and AmpFlSTR® Identifiler PCR Amplification kits, the alleged father and the two children were apparently homozygous at the FGA locus, but using the PowerPlex® 16 kit the three individuals were found to be heterozygous. Drop‐out was caused by a single mutation event in the presumptive binding site of the reverse primer. In addition, three inconsistencies were detected between the daughter and the alleged father among 18 STR markers. The occurrence of the rare null allele at the FGA locus and case history suggested that the true father was the brother of the alleged father. Furthermore, a single‐step repeat maternal mutation was also detected at D16S539. This puzzling case was solved by using multiple analytical approaches, including the use of different primer pairs, the use of a high number of STR markers, and the characterization of the mutation causing the “null allele.”
Does crop insurance influence agrochemical uses under current Chinese situations? A case study in the Manasi watershed, Xinjiang
Authors: Zhong Funing , Ning Manxiu , Xing Li
Published: February 2007

Government subsidy to crop insurance has been advocated as a policy alternative to support growth of agricultural production and farmers' income in China since the country joined the WTO. However, cautions have been raised as the crop insurance program may impact the environment negatively. This study tries to explore farmers' behaviors with regard to agrochemical use with household data applied to a simultaneous equation system consisting of disaggregated input models. It is found that decisions on fertilizer, pesticides, and agro‐film applications do have different impacts on crop insurance participation, and are influenced by the latter in different ways. It is also implied that encouraging farmers' participation in crop insurance under current low‐premium and low‐indemnity terms does not have a significantly negative impact on the environment.