bluuebunny/crossref_metadata_2025 huggingface dataset:
Errors in the estimation of soil water properties and their propagation through a hydrological model
Authors: Leenhardt D.
Published: February 2007

Abstract. The Agricultural Catchments Research Unit model (ACRU) includes a decision support system (DSS) for estimating the water content of soil at field capacity (θfc) and wilting point (θwp) when these characteristics are not directly measurable. Three methods of estimation are proposed: (a) based on silt and clay content and bulk density, (b) based on clay content only, and (c) based on soil series. These three pedotransfer functions are compared with respect to both the estimation of θfc and θwp and the propagation of errors when the actual evapotranspiration of a wheat crop (E) is predicted over the growing season by the ACRU model.

The standard error of estimation was between 0.066 and 0.082 m3/m3 for θfc, between 0.056 and 0.069 m3/m3 for θwp and between 29.9 and 34.8 mm of water for E. The method based on silt and clay contents and bulk density predicted θfc and θwp for non‐swelling soils most precisely. The method based on soil series was better than other methods for swelling soils. It also performed better for estimating available water capacity and consequently for predicting E from a conceptual soil water model. The propagated error of estimating θfc and θwp using the DSS reached 15–18% of the simulated E. The error in the prediction of E can reach 26–30% when spatial variation in soil properties is also estimated.
The nature, causes and implications of water erosion on arable land in Scotland
Authors: Davidson D.A. , Harrison D.J.
Published: February 2007

Abstract. Erosion was surveyed in Strath Earn, Scotland, following severe weather conditions during the first 18 days of January, 1993. A rapid field mapping system was devised to record the nature of erosion. A total of 208 fields was surveyed and 76 exhibited erosion. Most fields with erosional features were either ploughed or in autumn cereals. The most common form of erosion was ephemeral gullies along topographic hollows. This erosion was primarily associated with ploughed land whereas sheetwash and rill erosion occurred more on autumn sown land. Land use change and climatic variability, especially increasing rainfall over the last 20 years, account for the incidence of erosion. Individual erosion events rarely cause major problems for farmers, but the increasing frequency of erosion events raises important questions for sustainable land use in the arable areas of Scotland.
Resurrection of Soil Surveys: a case study of the acid sulphate soils of The Gambia.
Authors: Dent D.L. , Ahmed F.B.
Published: February 2007

Abstract. Statistical techniques are used to test and re‐interpret archival data from soil surveys of the tidal floodplain of the River Gambia. Key soil attributes include salinity, ripeness and the acid sulphate hazard. Soil taxonomic units derived by cluster analysis of all the validated data do not correspond with the intuitively‐defined soil series of the original surveys. However they do correspond with practical soil mapping units, and distinguish areas of quite different geotechnical behaviour, kinds and degrees of salinity and acid sulphate hazard.
Simulating the impact of irrigation management on the water and salt balance in drained marsh soils (Marismas, Spain)
Authors: Andreu L. , Jarvis N.J. , Moreno F. , Vachaud G.
Published: February 2007

Abstract. Using the simulation model MACRO, this paper investigates the likely consequences of reduced irrigation inputs on the water and salt balance and crop growth in a drained, saline clay in a Mediterranean climate (Marismas, SW Spain). The model was first successfully validated against field measurements of the soil water and chloride balance, water table depths and drain outflows in the 1989 growing season. Three‐year simulations were then performed assuming two different irrigation applications (60 and 75% reductions from the 1989 amount) and two different frequencies (12 or 6 irrigations per growing season). The model predictions suggested that reduced irrigation may lead to up to a 15%) increase in the chloride content of the soil profile after 3 years. Also, despite overall reductions in water discharge, slight increases in chloride leaching via field drains (c. 4 to 8%) were predicted. The model demonstrated that encroachment of salt into the soil profile may he exacerbated by the non‐equilibrium nature of water flow and solute transport (‘by‐passing flow’) in structured clays. With reduced water supply for irrigation, more frequent applications may give marginally better crop yields for the same quantity of irrigation but at the expense of slightly increasing salt concentration in the root zone.
Spatial interpolation of soil hydraulic properties and simulated rice yield
Authors: Wopereis M.C.S. , Stein A. , Kropff M.J. , Bouma J.
Published: February 2007

Abstract. Simulated estimates of crop yield were made for rainfed rice in a 50 ha dryland rice area. The aim was to investigate how soil units and management units of different sizes with different yields could be used to obtain values for areas of land. Two procedures were applied. First, yields were simulated at six sites, that were representative of six soil mapping units. Second, yields were simulated using soil information from 133 auger sites, and were interpolated over management units using block kriging. Differences between the two procedures for the total area and for a test set of 22 additionally sampled locations were small. A 60% increase in precision was achieved when relatively large management units were defined.

A Geographical Information System was used to identify areas with greatest yield potential for rainfed dryland rice. Statistical analysis showed that the six soil units could be grouped into three yield classes. The largest yields were obtained for a sub‐area comprising 11% of the survey area which was associated with a slowly permeable Bg horizon in the soil profile.

It was concluded that the best procedure for the spatial interpolation of simulated rice yield should be based on preliminary simulation of crop yields. A sensitivity analysis of the impact of weather variability and soil heterogeneity on the variation of yield was useful to detect the importance of their contributions. The procedures developed in this study are of value in obtaining a reliable estimate of average yield, and can consequently be used for associated cost‐benefit calculations.
Agricultural improvement of cultivated organic soils II. Effects of liming and deep cultivation on soil properties and root development
Authors: Berglund K.
Published: February 2007

Abstract. The effect of liming and deep cultivation on soil properties and root development was investigated in two cultivated shallow fen peats resting on acid gyttja (lake mud) soils. Root growth was in general dependent on soil pH and aluminium content of the soil. A soil pH (H2O) below 5 adversely affected roots and a pH below 4 severely restricted root growth. Liming of the topsoil or the subsoil and to some extent deep cultivation improved root growth. Increased rooting depth made it possible for plants to utilize soil water to a greater depth in the profile and to support a larger crop yield.
Changes in soil acidity and related variables over 25 years in the North Pennine Uplands, UK
Authors: Adamson J.K. , Rowland A.P. , Scott W.A. , Hornung M.
Published: February 2007

Abstract. Soil profiles, first sampled between 1963 and 1973, were resampled in 1991 in an upland area with modertely high deposition of pollutants. One hundred horizons from 32 profiles, representing 10 different soil subgroups were analysed for pH and seven variables related to pH, using the same laboratory methods on both sampling occasions. To allow comparisons to be made with results obtained with these old methods, analysis of the 1991 samples was repeated for some determinands using the methods currently used in the analytical laboratory. Organic and A horizons show a consistent increase in acidity between samplings. Although brown soils and lithomorphic soils have increased in acidity throughout their depth, gleys and podzols have decreased in acidity at depth, probably because of poor water transmission downwards into these horizons. Correlations with other determinands suggest that the dominant process in the soils is leaching of basic cations and their replacement on exchange sites by protons and probably aluminium ions. A cause of the increase in soil acidity is likely to be the deposition of atmospherically transported pollutants.
Release of bromide following rewetting of a naturally drained acid gully mire
Authors: Hughes S. , Reynolds B. , Hudson J.
Published: February 2007

Abstract. Currently there is growing interest in the restoration of drained peatlands in Britain. In order to investigate some of the effects of changes in land management practices on the biogeochemistry of peatlands, a field experiment was designed to manipulate the hydrological conditions in a naturally drained acid gully mire in Mid‐Wales. We report preliminary results of the effects of experimentally rewetting the mire on the hydrochemistry of bromide in the peat‐water. Results show that rewetting had a dramatic effect on the concentrations of bromide, which increased substantially. Peak values approached 1 mg/dm3 in some samples following rewetting, compared with typical values < 0.05 mg/dm3 under the drained conditions. Bromide was positively and significantly correlated with Dissolved Organic Carbon (DOC) in the peat‐water, which suggests that Br‐ is derived from breakdown of organic matter in the reducing conditions following rewetting. The bromide mobilized by rewetting may be leached out of the system and/or re‐assimilated by the wetland vegetation. Further monitoring is needed to determine whether the observed hydrochemical response of bromide to rewetting of the mire has any longer‐term effects.
Decomposition in a peaty soil improved for pastoral agriculture
Authors: Hopkins D. W.
Published: February 2007

Abstract. The rates of CO2 production and decomposition of 13C‐enriched Lolium perenne leaves and roots in soil from the surface five cm of two upland stagnohumic gley soils were measured in laboratory experiments. One of the soils had been limed (pH 6.8) 13 years earlier. The other was unlimed (pH 3.7). Liming increased the rate of CO2 release from soil to which no L. perenne had been added. About 30% of the 13C in L. perenne leaves remained in both limed and unlimed soil after 224 days. By contrast, less 13C‐remained in the limed soil amended with L. perenne roots (44%) than in the limed soils (55%). Although the daily rate of CO2 from the plant material‐amended soils was initially greater in the improved than in the unimproved soil, it subsequently declined more rapidly.
Dynamic model for the effects of K fertilizer on crop growth, K‐uptake and soil‐K in arable cropping. 2. Field test of the model
Authors: Greenwood D. J. , Karpinets T. V.
Published: February 2007

Abstract. The validity of the model described in Greenwood & Karpinets (1997) was tested against the results of single year, multi level K fertilizer experiments. Measurements of plant mass, %K in the plant and K activity ratio in soil had been made at harvest and at intervals during the growing season on spring wheat, summer cabbage and turnips. Reasonably good agreement was obtained between these measurements and simulated values when the two ‘crop’ parameters (defining the dependence of critical and maximum possible %K on plant mass) were adjusted for each crop. Also good agreement was generally obtained for plant weight and plant %K at harvest in less detailed experiments on 10 other crops. Values of the two ‘crop’ parameters for 12 of the crops were strongly correlated with one another suggesting that a single ‘crop’ parameter may be all that is required to define most inter‐species differences in plant‐K demand.

Simulations with the model indicate that, in central England, no response of 10 crops to K fertilizer would be likely on soils containing more than 170 mg of 1 M ammonium nitrate extractable‐K/kg of soil and having clay contents of between 15 and 45%. Shortcomings of the model and opportunities for advance are discussed.

A simplified version of the model runs on the Internet at: http://www.qpais.co.uk/moda‐djg/potass.htm
Traditional soil and land appraisal on fadama lands in northeast Nigeria
Authors: Kundiri A. M. , Jarvis M. G. , Bullock P.
Published: February 2007

Abstract. As part of a study of recession farming on the ‘fadama’ lands on a segment of the Komadugu‐Yobe floodplain, a survey was carried out to investigate the local farmers’ perception of soil types and management practices. The farmers are clearly aware of the differences in soil type on the fadama and they possess unique skills in managing their farm lands. The farmers classify fadama soils for recession farming by assessing soil texture and soil drainage conditions by feel and observation. Integrating such local knowledge into soil surveys will lead to better practical definition of mapping units and give soil names that have more meaning for the farmers.
Fluxes of methane between landfills and the atmosphere: natural and engineered controls
Authors: Bogner J. , Meadows M. , Czepiel P.
Published: February 2007

Abstract. Field measurement of landfill methane (CH4) emissions indicates natural variability spanning more than seven orders of magnitude, from less than 0.0004 to more than 4000 g/m2 per day. This wide range reflects net emissions resulting from production (methanogenesis), consumption (methanotrophic oxidation), and gaseous transport processes. The determination of an ‘average’ emission rate for a given field site requires sampling designs and statistical techniques which consider spatial and temporal variability. Moreover, particularly at sites with pumped gas recovery systems, it is possible for methanotrophic microorganisms in aerated cover soils to oxidize all of the CH4 from landfill sources below and, additionally, to oxidize CH4 diffusing into cover soils from atmospheric sources above. In such cases, a reversed soil gas concentration gradient is observed in shallow cover soils, indicating bidirectional diffusional transport to the depth of optimum CH4 oxidation. Rates of landfill CH4 oxidation from field and laboratory incubation studies range up to 166 g/m2 per day, among the highest for any natural setting, providing an effective natural control on net emissions. It has been shown that methanotrophs in landfill soils can adapt rapidly to elevated CH4 concentrations with increased rates of CH4 oxidation related to depth of oxygen penetration, soil moisture, and the nutrient status of the soil.

Estimates of worldwide landfill CH4 emissions to the atmosphere have ranged from 9 to 70 Tg/y, differing mainly in assumed CH4 yields from estimated quantities of landfilled refuse. At highly controlled landfill sites in developed countries, landfill CH4 is often collected via vertical wells or horizontal collectors. Recovery of landfill CH4 through engineered systems can provide both environmental and energy benefits by mitigating subsurface migration, reducing surface emissions, and providing an alternative energy resource for industrial boiler use, on‐site electrical generation, or upgrading to a substitute natural gas. Manipulation of landfill cover soils to maximize their oxidation potential could provide a complementary strategy for controlling CH4 emissions, particularly at older sites where the CH4 concentration in landfill gas is too low for energy recovery or flaring. For the future, it is necessary to better quantify net emissions relative to rates of CH4 production, oxidation, and transport. Field measurements, manipulative studies, and model development are currently underway at various spatial scales in several countries
Structural improvement in a grassland soil after changes to wheel‐traffic systems to avoid soil compaction
Authors: Douglas J. T. , Koppi A. J. , Crawford C. E.
Published: February 2007

Abstract. We report on a study aimed at assessing improvements in soil structure that developed when a reduced ground‐pressure traffic system was introduced onto grassland previously compacted by conventional machinery traffic, and when a zero traffic system was introduced on land previously under a reduced ground‐pressure system. Increases in the volume, average size, and number of macropores, measured by image analysis, together with decreases in vane shear strength indicated structural improvement in soil under the substitute traffic systems relative to the same soil in the original systems. A smaller content of organic matter in the soil of the substitute systems than in the original systems was attributed to improved aeration and greater earthworm activity in the former.
Trends in the use of conservation tillage in US agriculture
Authors: Uri N. D.
Published: February 2007

Abstract. In 1996 conservation tillage was used on nearly 36% of the cropped area of the USA. This level has remained relatively unchanged over the past few years. The use of conservation tillage varied by crop and was dependent on site‐specific factors including soil type, topsoil depth, and local climatic conditions. A number of economic, demographic, geographic, and policy factors have affected the adoption of conservation tillage. While it was not possible to quantify exactly the impact of these factors, it was clear that management complexities and profitability are key factors impeding an increase.
Soil phosphorus management and water quality: a UK perspective
Authors: Edwards A. C. , Withers P. J. A.
Published: February 2007

Abstract. An increasing proportion of P reaching surface waters appears to be derived from agricultural land; apportioning the relative contribution to particular farming systems is not straightforward. The majority of farms in the UK operate on the basis of an annual agricultural P surplus, the size of which varies across different farm types. Particularly high values (>20kg ha‐1) are commonly associated with intensive‐livestock production and the lower values (<10kg P ha‐1) with arable farms. The geographical divide between the predominance of arable cropping in the east and livestock enterprises in the west of the UK should result in an uneven pattern to the distribution of annual P surplus. The expected cumulative effects of this surplus should be a noticeable increase in total and extractable soil P concentrations, but this is not readily apparent. While evidence from experimental plots suggests a relationship between the concentration of available soil P and that present in drainage waters, extrapolating this information so that it can be useful at the scale of a whole catchment is difficult. The loss of P from agricultural land is controlled by factors which are independent of the size of the annual P surplus. The pattern of P cycling, together with the dominant loss pathways, differ greatly between livestock and arable farming systems. Proportioning the contributions that either increased soil erosion arising from changing agricultural practices or the cumulative effect of a P surplus have had upon P loss is a necessary prerequisite to effective management.
Point/Counterpoint: The Role of Carotid Ultrasound
Authors: Spence J. David
Published: February 2007

Vascular prevention is most cost‐effective in high‐risk patients, but secondary prevention misses many opportunities. The high‐risk strategy‐identifying patients with high levels of risk factors‐is problematic because traditional risk factors predict only half of vascular events. In multiple regression, traditional risk factors explained only half of carotid atherosclerosis. New strategies are being explored, such as electron‐beam computerized tomographic measurement of coronary calcification, to identify high‐risk patients. Carotid plaque is a powerful tool for identifying and managing high‐risk vascular patients, as it explains twice as much of unexplained vascular risk as coronary calcium by electron beam computerized tomography, and it has significant advantages compared with intimal‐medial thickness. After adjustment for risk factors, patients in the highest quartile of baseline plaque area have 3.5 times the risk of stroke, death, or myocardial infarction compared with those in the lowest quartile. Those with regression or stable plaque have half the risk of those with progression after adjustment for the same panel of risk factors. The therapeutic target is plaque regression or stabilization, not just control of traditional risk factors. Trying to treat arteries without measuring plaque is like trying to treat hypertension without measuring the pressure, or hyperlipidemia without measuring the lipids.
The Role of Statins in Preventing Stroke
Authors: Trubelja Nenad , Vaughan Carl , Coplan Neil L.
Published: February 2007

Epidemiological studies have not demonstrated a clear relationship between stroke risk and hypercholesterolemia. Clinical trials using statins have demonstrated a reduction in stroke, in particular, in patients with established coronary artery disease. The disparity between epidemiological and clinical studies suggests hypercholesterolemia is a true risk factor for stroke that evaded detection in epidemiological studies, or that statins possess other properties that render them useful in stroke prevention. These effects have been loosely termed “pleiotropic” in the lipid literature and revolve around putative effects of statins on endothelial function, inflammation, thrombosis, plaque stability, and immune regulation. Questions remain as to the mechanisms of benefit of statin therapy in stroke prevention, the role of statins in the primary prevention of stroke, and the role of statins in modulating the immune system in the brain.
Use of the Cell Phone for Transmission of the Pulse Rate From a Subject in Motion
Authors: Uhley Herman
Published: February 2007

A method of transmitting the sound produced by cardiac electrical activity to a remote site using the cell phone is described. The use of the cell phone system permits transmission of the click produced by the heartbeat from a subject in motion who may be far away, as well as in close proximity.
Achieving National Cholesterol Education Program Goals in Coronary Artery Disease
Authors: Rondina Matthew T. , Zebrack James S.
Published: February 2007

National Cholesterol Education Program (NCEP) guidelines recommend low‐density lipoprotein cholesterol (LDL‐C) levels <100 mg/dL for patients with coronary artery disease (CAD) and lipid‐lowering therapy if LDL‐C remains >100–130 mg/dL after dietary intervention. Studies consistently report that the majority of CAD patients do not achieve NCEP goals in clinical practice; we sought to determine if our practice fared better. We performed a retrospective chart review of 600 CAD patients followed by cardiologists. The mean age was 69, and 66% of patients were male. Of persons with a cardiology clinic lipid profile (60%), most (76%) achieved an LDL‐C <100 mg/dL; however, only 61% were treated to the NCEP secondary goal of non‐HDL‐C <130 mg/dL. Of patients not at an LDL‐C goal, 81% were on lipid‐lowering therapy, but only 18% were on maximal statin doses and 6% on combination therapy. We concluded that the majority of CAD patients have had recent lipid measurements and are treated according to NCEP guidelines, but many patients remain on suboptimal therapy.
Characteristics and Management of Patients Presenting to the Emergency Department With Hypertensive Urgency
Authors: Bender Seth R. , Fong Michael W. , Heitz Sabine , Bisognano John D.
Published: February 2007

Few studies have examined the characteristics of patients presenting with hypertensive urgency, factors contributing to their presentation, or their management. The time and cost associated with treatment are unknown. Retrospective analysis of 50 emergency department patients with hypertensive urgency (symptomatic blood pressure (BP) elevation focusing on systolic BP >180 mm Hg or diastolic BP >110 mm Hg) was performed. The hospital database was queried to determine the cost of the average treat‐and‐release visit. The mean age was 54.3±15.6 years; 64% were female; 46% were black; 90% had diagnosed hypertension. The mean presenting BP was 198±27.6/109±17.3 mm Hg; 66% had systolic BP >180 mm Hg, and 38% had diastolic BP >110 mm Hg. Initially, 30% were not on antihypertensives, and 28% were on monotherapy. Headache (42%) and dizziness (30%) were most frequently reported symptoms. Presentation was most often attributed to running out of medication (16%). IV and oral labetalol were given to 28% and 24% of patients, respectively. Fifty‐six percent of patients had no change in baseline therapy at discharge. The average emergency department stay was 5 hours 17 minutes ± 4 hours 27 minutes. The average cost for similar visits in 2004 was $1543 per visit. Emergency department visits for hypertensive urgency are related mostly to noncompliance. Labetalol was the most frequently used therapy. Management in the primary care office could result in substantial cost savings.
An Effectiveness Study Comparing Algorithm‐Based Antihypertensive Therapy With Previous Treatments Using Conventional and Ambulatory Blood Pressure Measurements
Authors: Weber Michael A. , White William B. , Giles Thomas D. , Bakris George L. , Neutel Joel M. , Smith David H.G. , Davidai Giora
Published: February 2007

Effectiveness trials in hypertension enable the efficacy and safety of new drugs to be compared with previous therapy. Since these open‐label trials could inadvertently be influenced by observer bias, this study has used ambulatory blood pressure monitoring (ABPM) to provide a rigorous blinded end point to validate the study conclusions. The study was performed in 675 patients with stage 1 or 2 hypertension despite receiving single‐agent or fixed‐dose combination therapy. After baseline ABPM, the previous treatment was replaced by telmisartan 40 mg daily; if control (office blood pressure <140/90 mm Hg) was not achieved in 2 weeks, the dose was increased to 80 mg, and if necessary, a fixed combination with hydrochlorothiazide 12.5 mg was used after a further 4 weeks. ABPM was repeated after 4 weeks on final therapy. Overall, 50% of patients finished on monotherapy and 50% on combination therapy. By office measurements, there was a decrease (mean ± SEM) of 16.8±0.5/10.3±0.3 mm Hg (p<0.001) when telmisartan‐based treatment replaced previous treatment; by ABPM, the decrease was 8.2±0.4/5.0±0.2 mm Hg (p<0.001). The decreases were significant for comparisons with each of the prior drug classes. A treatment algorithm based on the angiotensin receptor blocker, telmisartan, was confirmed by the blinded end point of ABPM as an efficacious alternative to other antihypertensive regimens in clinical practice.
Out‐of‐Office Blood Pressures—Are They Helpful in Guiding the Treatment of Hypertension Patients?
Authors: Moser Marvin , Townsend Raymond , Kaplan Norman
Published: February 2007

Following a hypertension symposium in Philadelphia in September 2005, a roundtable was convened to discuss the significance of out‐of‐office blood pressure. Dr. Marvin Moser of the Yale School of Medicine, New Haven, CT, moderated the panel discussion. Participants included Dr. Raymond Townsend of the University of Pennsylvania School of Medicine, Philadelphia, PA, and Dr. Norman Kaplan of the University of Texas Health Science Center in Dallas, Dallas, TX.
Clinical Hypertension Research Tools: The Randomized Controlled Clinical Trial
Authors: Lackland Daniel T. , Woolson Robert F.
Published: February 2007

The randomized clinical trial is used in hypertension research as a primary mode for evaluating new, promising therapies. Herein, the authors provide an overview of design features of clinical trials, particularly those useful for designing a hypertension therapeutic clinical trial.
Early Morning Blood Pressure Surge
Authors: Gosse Philippe , Schumacher Helmut
Published: February 2007

Alterations in the circadian rhythm of blood pressure, Alterations in the circadian rhythm of blood pressure, risk. Estimates of the magnitude of the blood pressure surge on rising vary depending on technique and population, but it is usually around 10–30 mm Hg systolic and 7–23 mm Hg diastolic. The magnitude of the surge increases with age, alcohol consumption, and smoking and is greater in whites. Blood pressure variations and morning plasma aldosterone are closely correlated. A high morning surge is linked to increased target organ damage as well as strokes and other cardiovascular complications. Therapeutic options exist to reduce the magnitude of the morning blood pressure surge—notably, the use of drugs with a long duration of action, the use of medications that specifically antagonize the morning surge (such as α blockers), and the administration of drugs upon awakening but before rising.
Hypertension in Older People: Part 1
Authors: Franklin Stanley S.
Published: February 2007

Once considered part of the normal aging process, the development of isolated systolic hypertension represents a late manifestation of increased arterial stiffness in older people. Furthermore, isolated systolic hypertension is the single most frequent subtype of hypertension in the US adult population. Indeed, central arterial stiffness rather than peripheral vascular resistance becomes the dominant hemodynamic factor in both normotensive and hypertensive individuals after the age of 50–60 years. Stiffening disease, an age‐related degeneration of the elastic elements of the thoracic aorta, is associated with a widening of brachial pulse pressure. Brachial pulse pressure predicts future cardiovascular disease events. However, pressure wave amplification produces higher brachial than aortic pressures and, therefore, central rather than peripheral blood pressure indices are more reliable measures of cardiovascular risk. Stiffening disease of aging is accompanied by early wave reflection, which results in a significant augmentation of central systolic pressure in late systole and further adds to increased cardiac afterload—so‐called ventricular‐vascular uncoupling. Diabetes, impaired renal function, and untreated or poorly treated hypertension may lead to premature arterial stiffening; its consequences are stiffening and hypertrophy of the left ventricle and predisposition to coronary heart disease, heart failure, stroke, vascular dementia, and chronic kidney disease.
The Metabolic Syndrome—What Is It and How Should It Be Managed?
Authors: Moser Marvin , Falkner Bonita , Weber Michael A. , Keilson Leonard Mark
Published: February 2007

Following a hypertension symposium in Portland, ME, in October 2005, a roundtable was convened to discuss the metabolic syndrome and its significance. Dr. Marvin Moser of the Yale University School of Medicine, New Haven, CT, moderated the discussion. Participating in the discussion were Dr. Bonita Falkner of the Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA; Dr. Michael A. Weber of SUNY Downstate College of Medicine, New York, NY; and Dr. Leonard Mark Keilson of the University of Vermont College of Medicine.
Clinical and Nonclinical Correlates of Adherence to Prescribing Guidelines for Hypertension in a Large Managed Care Organization
Authors: Skelding Philip C. , Majumdar Sumit R. , Kleinman Ken , Warner Cheryl , Salem‐Schatz Susanne , Miroshnik Irina , Prosser Lisa , Simon Steven R.
Published: February 2007

To examine correlates of guideline adherence in a population with access to health care and prescription drug benefits, the authors conducted a crosssectional analysis among 5789 patients undergoing hypertension treatment with a single medication in a large New England managed care organization. Logistic regression was used to determine correlates of adherence, defined as use of diuretics or β blocker as antihypertensive monotherapy during the 1‐year study period. Women were more likely than men to receive guideline‐adherent therapy (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.45–1.85). Compared with patients covered by health maintenance organization plans, Medicare coverage was positively associated with guideline adherence (OR, 1.38; 95% CI, 1.13–1.69), but fee‐for‐service coverage was negatively associated (OR, 0.66; 95% CI, 0.48–0.91). Patient age was not a significant correlate of adherence to guidelines (OR, 1.01; 95% CI, 0.94–1.09). Understanding these observations may lead to strategies to improve guideline adherence and reduce health care disparities.
Changing Patterns of Initial Drug Therapy for the Treatment of Hypertension in a Medicaid Population, 2001–2005
Authors: Weiss Robert , Buckley Kevin , Clifford Timothy
Published: February 2007

Thiazide diuretics have been recommended as one preferred choice for the initial treatment of hypertension. This study was undertaken to determine whether Maine physicians initiating monotherapy for newly diagnosed hypertensive patients from 2001–2005 used this guideline. The Maine Medicaid database was searched for the drug classes used to initiate monotherapy for patients followed for at least 6 months. A total of 5373 patients were included. In 2001, the use of β‐blockers was 23.5%, diuretics 17.5%, angiotensin‐converting enzyme inhibitors 37.5%, calcium channel blockers 9.5%, angiotensin receptor blockers 3.8%, and others 8.2%. By 2005, the use of β‐blockers was 27.8%, diuretics 25.5%, angiotensin‐converting enzyme inhibitors 30.9%, calcium channel blockers 6.4%, angiotensin receptor blockers 1.6%, and others 7.7%. There was an increase in the use of angiotensin‐converting enzyme inhibitors or angiotensin receptor blockers in diabetics but no other condition affected drug choice. Although there was an increase in the use of diuretics as initial therapy in 2003 and 2004, this decreased in 2005. The increase in initial diuretic use was not reflected in patterns of ongoing antihy per tensive use from 1997 to 2005. There appears to have been limited impact from the guidelines on initial drug choice and even less so on ongoing drug therapy.
Considerations for the interpretation of STR results in cases of questioned half‐sibship
Authors: Allen Robert W. , Fu Jun , Reid Thomas M. , Baird Michael
Published: February 2007

Likelihood ratios (LRs) were calculated for a cohort of 60 pairs of true half‐sibs and compared with LR values calculated for unrelated, paired children. STR results for the half‐sib group were obtained from 60 archived cases involving a true mother, two children, and an alleged father subjected to typing with a multiplex STR kit (Identifiler multiplex, Applied Biosystems) and in which the alleged father was excluded as the father of only one of the two children (half‐sib pairs). The distribution of LR values among true half‐sibs was compared to those produced from paired, unrelated children selected in two ways: One method for producing unrelated pairs was to randomly select Identifiler profiles from children in 120 distinct paternity cases and group them into 60 ethnically matched pairs (random pairs). In a second approach, the children in the true half‐sib group were shuffled and ultimately paired with someone from a different case. A total of 49 ethnically matched, unrelated pairs were created (shuffled pairs). In the shuffled pairs group, comparisons were thus based on a constant set of phenotypes. LRs comparing the probability of half‐sibship versus being unrelated were produced for all groups with standard methods. Among pairs of known half‐sibs, LRs ranged from a low of 0.1 to a maximum of 3763. Among random and shuffled pairs, LRs ranged from a low of 0.0001 to 12 for shuffled pairs or 42 for random pairs. LRs of greater than 2 were produced in 8 instances among random pairs and in 4 instances among the shuffled pairs. Overall, results suggest that half‐sib indices of 30 or greater are fairly characteristic of individuals who are related as half‐sibs. In contrast, half‐sib indices of 0.1 or less are fairly characteristic of unrelated individuals who claim to be half‐sibs. LRs falling between 0.1 and 10.0 are uninformative, as this region represents the overlap in the LR distributions produced from the true and false half‐sib groups when the Identifiler multiplex kit is used for testing.
Double‐Wire Technique in Balloon‐Protected Carotid Artery Stenting
Authors: KAWARADA OSAMI , YOKOI YOSHIAKI , TAKEMOTO KAZUSHI , MORIOKA NOBUYUKI
Published: February 2007

Objectives: To evaluate the safety and efficacy of a double‐wire technique in carotid artery stenting (CAS) with a distal occlusion balloon system, PercuSurge GuardWire.

Methods: Fifty‐one consecutive patients with 53 de novo lesions were scheduled to undergo balloon‐protected CAS with the “double‐wire technique,” the use of two wires, one for independent predilatation and the other for stent implantation.

Results: Fifty consecutive patients underwent a total of 52 balloon‐protected CAS except for 1 patient with one lesion that could not be accessed. The use of a 1.5‐mm coronary balloon was necessary in only 2 cases (3.8%) to let the PercuSurge GuardWire cross critically stenotic lesions. The placement of the PercuSurge GuardWire into the internal carotid artery was successful in all cases. Technical success was obtained in all cases. Fifty lesions (96.2%) were treated with one inflation of the distal occlusion balloon during the entire procedure consisting of predilatation, stent implantation, and aspiration, and among them three lesions (5.8%) required postdilatation. The mean occlusion time of cerebral blood flow for 50 lesions was 266 ± 37 seconds. Out of 50 procedures, 45 (90.0%) had occlusion times of 300 seconds or less. Neurological intolerance requiring intravenous anesthesia was seen in 4 cases (7.7%) and periprocedural neurological complication in 2 cases (3.8%).

Conclusions: The “double‐wire technique” is safe and effective for the shortening of occlusion time during predilatation, stent implantation, and aspiration, leading to satisfactory technical and clinical outcomes, in most cases. This technique should be considered for balloon‐protected CAS using the PercuSurge GuardWire.
Transesophageal Echocardiography and Intracardiac Echocardiography Differently Predict Potential Technical Challenges or Failures of Interatrial Shunts Catheter‐Based Closure
Authors: RIGATELI GIANLUCA , CARDAIOLI PAOLO , BRAGGION GABRIELE , AGGIO SILVIO , GIORDAN MASSIMO , MAGRO BEATRICE , NASCIMBEN ALBERTO , FAVARO ALBERTO , RINCON LORIS
Published: February 2007

We sought to prospectively assess the role of transesophageal (TEE) and intracardiac echocardiography (ICE) in detecting potential technical difficulties or failures in patients submitted to interatrial shunts percutaneous closure. We prospectively enrolled 46 consecutive patients (mean age 35±28, 8 years, 30 female) referred to our center for catheter‐based closure of interatrial shunts. All patients were screened with TEE before the intervention. Patients who met the inclusion criteria underwent ICE study before the closure attempt (40 patients). TEE detected potential technical difficulties in 22.5% (9/40) patients, whereas ICE detected technical difficulties in 32.5% (13/40 patients). In patients with positive TEE/ICE the procedural success (92.4% versus 100% and, P = ns) and follow‐up failure rate (7.7% versus 0%, P = ns) were similar to patients with negative TEE/ICE, whereas the fluoroscopy time (7 ± 1.2 versus 5 ± 0.7 minutes, P < 0.03), the procedural time (41 ± 4.1 versus 30 ± 8.2 minutes, P ± 0.03), and technical difficulties rate (23.1% versus 0%, P = 0.013) were higher. Differences between ICE and TEE in the evaluation of rims, measurement of ASD or fossa ovalis, and detection of venous valve and embryonic septal membrane remnants impacted on technical challenges and on procedural and flouroscopy times but did not influence the success rate and follow‐up failure rate.
Typing the 1.1 kb Control Region of Human Mitochondrial DNA in Japanese Individuals
Authors: Mabuchi Tadashi , Susukida Rie , Kido Akira , Oya Masakazu
Published: February 2007

ABSTRACT: This study presents a reliable method that uses high‐fidelity long‐range PCR and optimized primers to assess polymorphism and to genotype human mitochondrial DNA (mtDNA). This method was used to analyze polymorphic sites in the human mtDNA control region, including hypervariable regions I, II, and III (HVI, HVII, and HVIII), from 124 unrelated Japanese individuals. In HVI, HVII, and HVIII, 80, 37, and 14 polymorphic sites were identified, respectively, excluding those in the homopolymeric cytosine stretch (C‐stretch) regions. The region between HVI and HVII also contained 15 polymorphic sites. On the other hand, C‐stretch length heteroplasmy in HVI or HVII was observed in 66 of 124 Japanese individuals (53%), which is much higher than in Caucasian populations. The variants in the C‐stretch regions were characterized by counting the number of heteroplasmic peaks split from the single peak in homoplasmic sequences (i.e., 16244G and 16255G in HVI and 285G in HVII). Including the C‐stretch length heteroplasmy, the 124 Japanese mtDNA samples were classified into 116 distinct haplotypes. The random match probability and the genetic diversity were estimated to be 0.95% and 0.998581, respectively, indicating that the method presented here has higher discrimination than the conventional method for mtDNA typing using HVI and HVII. [Correction added after publication 30 January 2007: in the preceding sentence random match probability and genetic diversity estimates were corrected from 0.95 and 0.998581%, respectively, to 0.95% and 0.998581, respectively.] The haplogroups and their frequencies observed in this study (i.e., D4; 13.7%, M7a1; 11.3%, D4a; 9.7% and M7b2; 8.9%) were similar to those observed in other studies of Japanese mtDNA polymorphism. The method described here is suitable for forensic applications, as shown by successful analysis of tissues from highly putrefied remains of an infant, which allowed maternal relationship to be determined via mtDNA haplotyping.
Optimal supplier testing and tolerance strategies for genetically modified (GM) wheat
Authors: Wilson William W. , Dahl Bruce L. , Jabs Eric
Published: February 2007

A stochastic optimization model was developed to determine optimal testing strategies, costs, and risks for dual marketing of genetically modified (GM) and non‐GM wheat in an export supply chain. The optimal testing strategy is derived that minimizes disutility of additional system costs due to testing and quality loss. Cost components were estimated including those related to testing, quality loss, and a risk premium to induce shippers to undertake dual marketing as opposed to handling only non‐GM crops. Uncertainties were incorporated for adventitious presence and commingling, variety declaration, and test accuracy. Sensitivities were performed for effects of variety risks and declaration, penalty differentials, buyer tolerances, risk aversion, and GM adoption. Results indicate testing and segregation can be performed at a relatively low cost and risk to buyers.
Economic implications of alternative mill mud management options in the Australian sugar industry
Authors: Qureshi Muhammad E. , Qureshi Sumaira E. , Wegener Malcolm K.
Published: February 2007

Sugar mills produce a range of byproducts during the process of extracting sugar from cane. Mill mud is one of the byproducts produced in significant volume. The practice of spreading mill mud onto cane fields close by the mill has been the primary means of disposing of mill mud for many years. The continued application of mill mud at high rates, without appropriate recognition of its nutrient content, the soil condition, crop nutrient requirements, slope of the land, or proximity of application sites to environmentally sensitive areas has raised a number of concerns in recent years, including overfertilization, heavy‐metal contamination, leaching, and offsite impacts from drainage to waterways. This study develops a regional mathematical programming model to determine optimal rates of mill mud application for various soil types and distances from the mill in the Mackay region in central Queensland, Australia. The optimal application rate of mill mud varies according to soil type and by distance from the mill. Lower rates of mill mud application are economically desirable at greater distances from the mill. However, when the cost of mill mud application is shared between growers and the mill operator, the optimal application rates are reduced at some locations while increasing at others.
Effect of limbal explant orientation on the histology, phenotype, ultrastructure and barrier function of cultured limbal epithelial cells
Authors: Raeder Sten , Utheim Tor Paaske , Utheim Øygunn Aass , Cai Yiqing , Roald Borghild , Lyberg Torstein , Kjeldsen‐Kragh Jens , Ramstad Hanne , Messelt Edvard , Nicolaissen Bjørn
Published: February 2007

Purpose:  To compare the histology, phenotype, ultrastructure and barrier function of cultured limbal epithelial cells using two explant culture protocols.

Methods:  Epithelial cells were cultured for 16 days from limbal explants, positioned with either the stromal side (stromal group) or the epithelial side (epithelial group) on intact amniotic membranes. The cultured epithelium (n = 56) was examined using light microscopy, immunohistochemistry for K3, Cx43, ABCG2 and p63 expression, Western blot analysis of ΔNp63α, transmission electron microscopy, a horseradish peroxidase (HRP) permeability assay and scanning electron microscopy.

Results:  The epithelial group demonstrated a significantly higher expression of p63‐positive cells (85.7 ± 4.2%) than the stromal group (75.3 ± 8.9%), and Western blots showed a stronger band of ΔNp63α. K3 and ABCG2 were not detected in either group, whereas Cx43 displayed moderate immunostaining in the suprabasal layer. The number of cell layers, the desmosome number and the undulation length in the epithelial group were not significantly different from those in the stromal group. In both groups, HRP accumulated on the apical surface of the superficial cells, and scanning electron microscopy demonstrated tightly apposed superficial cells.

Conclusions:  Our findings indicate that limbal explants positioned epithelial side down may give rise to cultured epithelia with higher expression of p63 and ΔNp63α.
Clinical, social and psychosocial factors associated with self‐rated oral health in Brazilian adolescents
Authors: Pattussi Marcos P. , Olinto Maria Teresa Anselmo , Hardy Rebecca , Sheiham Aubrey
Published: February 2007

Abstract –  Objective:  The objective of this study is to investigate the main social, psychosocial and clinical factors associated with poor self‐rated oral health in adolescents.

Methods:  A cross‐sectional survey was carried out in two cities of the Distrito Federal, Brazil. Data were collected by clinical examinations and by self‐administered questionnaires from 1302 adolescents aged 14‐ 15 years in 39 schools. Data analysis was carried out using a Poisson regression model taking into account the cluster sample.

Results:  Adjusting for social, psychosocial and clinical factors, results showed that poor self‐rated oral health was significantly associated (P < 0.001) with sex (males) [prevalence ratio (PR) = 0.8, 95% confidence interval (95% CI): 0.7–0.9]; low social class (PR =1.4, 95% CI: 1.2–1.6); poor self‐rated general health (PR = 2.6, 95% CI: 2.3–3.1); mouth appearance (PR = 1.9, 95% CI: 1.6–2.2) and with presence of untreated dental decay (PR = 1.4, 95% CI: 1.3–1.6).

Conclusions:  The single question on self‐rated oral health appears to be a simple and easy way to collect dental health information in adolescents. Assessment and understanding of self‐rated oral health should take into account social, psychosocial and oral factors.