bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Controlling Sorption of Prosulfuron by Variable‐Charge Soils and Model Sorbents
Authors: Hyun Seunghun , Lee Linda S.
Published: June 2010

Prosulfuron [1‐(4‐methoxy‐6‐methyltriazin‐2‐yl)‐3‐[2‐(3,3,3‐trifluoropropyl) phenylsulfonyl]‐urea), a relatively new sulfonylurea herbicide, is a weak acid (pKa 3.76), and therefore, will undergo pH‐dependent speciation and sorption. Understanding prosulfuron sorption in soils is important for predicting its environmental fate. Soil and solution factors controlling sorption were investigated by measuring prosulfuron sorption on five model sorbents (amorphous silica, α‐alumina, CaSWy1 montmorillonite, commercial humic acid, and anion exchange resin) and 10 variable‐charge soils from CaCl2 and Ca(H2PO4)2 solutions as a function of pH and ionic strength. Anion exchange of prosulfuron accounted for up to 82% of overall sorption in the pH range from 3 to 7. The relative importance of anion exchange to prosulfuron sorption was positively correlated to the ratio of anion and cation exchange capacities. Comparison between organic carbon (OC)‐normalized sorption (Koc) versus pH for humic acid and variable‐charge soils show similar trends with sorption decreasing with increasing pH. However, Koc values estimated from variable‐charge soils in the lower pH range where anion exchange has the greatest contribution to sorption was almost one log unit greater than that estimated from humic acid clearly exemplifying the impact of anion exchange. Similarity in Koc–pH curves for humic acid and variable‐charge soils may result from the fact that (i) cation exchange capacity increases with increasing OC content, thus effective anion exchange capacity is reduced; and (ii) the relative contribution of hydrophobic and hydrophilic sorption mechanisms was fairly constant. Given that both hydrophilic and hydrophobic sorption of prosulfuron decrease with increasing pH, addition of fertilizer and lime amendments may enhance the potential for off‐site leaching of recently applied acidic pesticides.
Differences in the Effects of Simulated Sea Aerosol on Water Relations, Salt Content, and Leaf Ultrastructure of Rock‐Rose Plants
Authors: Sánchez‐Blanco M. J. , Rodríguez P. , Olmos E. , Morales M. A. , Torrecillas A.
Published: June 2010

White‐leaf rock‐rose (Cistus albidusL.) and Montpellier rock‐rose (C. monspeliensisL.) plants were sprayed 2 to 3 min per day over a 7‐d period, in an unheated plastic greenhouse, with different aqueous solutions containing deionized water alone (control); an anionic surfactant (sodium dodecylbenzenesulfonate 82.5%, 50 mg L−1) (S1); a solution simulating the composition of sea aerosol (S2); and a solution simulating sea aerosol with anionic surfactant (S3). White‐leaf rock‐rose was more sensitive to sea aerosol, showing greater leaf damage and markedly decreased growth, and the presence of surfactant enhanced the phytotoxic effect leading to greater increases in mortality. Montpellier rock‐rose did not appear to be more adversely affected when surfactant was used in combination with sea aerosol, and manifested slight or less severe symptoms than white‐leaf rock‐rose. There was a significant increase in leaf turgor potential in the plants treated with both sea aerosol treatments by osmotic adjustment effect. The decrease in photosynthesis level seems to be due to both stomatal and nonstomatal factors. The results of microscopical analysis of Montpellier rock‐rose plants show that sea aerosol treatment caused alterations in the chloroplast structure, reducing the starch grain and swelling the thylakoid membranes. The results of this study indicated that Montpellier rock‐rose was more tolerant to sea aerosol than white‐leaf rock‐rose, showing a lower reduction in plant growth and less leaf damage, probably because of its ability to compartmentalize the toxic ions at the intracellular level.
Surface Runoff Losses of Phosphorus from Virginia Soils Amended with Turkey Manure Using Phytase and High Available Phosphorus Corn Diets
Authors: Penn C. J. , Mullins G. L. , Zelazny L. W. , Warren J. G. , McGrath J. M.
Published: June 2010

Many states have passed legislation that regulates agricultural P applications based on soil P levels and crop P uptake in an attempt to protect surface waters from nonpoint P inputs. Phytase enzyme and high available phosphorus (HAP) corn supplements to poultry feed are considered potential remedies to this problem because they can reduce total P concentrations in manure. However, less is known about their water solubility of P and potential nonpoint‐source P losses when land‐applied. This study was conducted to determine the effects of phytase enzyme and HAP corn supplemented diets on runoff P concentrations from pasture soils receiving surface applications of turkey manure. Manure from five poultry diets consisting of various combinations of phytase enzyme, HAP corn, and normal phytic acid (NPA) corn were surface‐applied at 60 kg P ha−1to runoff boxes containing tall fescue (Festuca arundinaceaSchreb.) and placed under a rainfall simulator for runoff collection. The alternative diets caused a decrease in manure total P and water soluble phosphorus (WSP) compared with the standard diet. Runoff dissolved reactive phosphorus (DRP) concentrations were significantly higher from HAP manure‐amended soils while DRP losses from other manure treatments were not significantly different from each other. The DRP concentrations in runoff were not directly related to manure WSP. Instead, because the mass of manure applied varied for each treatment causing different amounts of manure particles lost in runoff, the runoff DRP concentrations were influenced by a combination of runoff sediment concentrations and manure WSP.
Nitrogen and Phosphorus Flux Rates from Sediment in the Lower St. Johns River Estuary
Authors: Malecki Lynette M. , White John R. , Reddy K. R.
Published: June 2010

Internal cycling of nutrients from the sediment and water column can be an important contribution to the total nutrient load of an aquatic ecosystem. Our objective was to estimate the internal nutrient loading of the Lower St. Johns River (LSJR). Dissolved reactive phosphorus (DRP) and ammonium (NH4–N) flux from sediments were measured under aerobic and anaerobic water column conditions using intact cores, to estimate the overall contribution of the sediments to P and N loading to the LSJR. The DRP flux under aerobic water column conditions averaged 0.13 mg m−2 d−1, approximately 37 times lower than that under anaerobic conditions (4.77 mg m−2 d−1). The average NH4–N released from the anaerobic cores (18.03 mg m−2 d−1) was also significantly greater than in the aerobic cores for all sites and seasons, indicating the strong relationship between nutrient fluxes and oxygen availability in the water column. The mean annual internal DRP load was estimated to be 330 metric tons (Mg) yr−1, 21% of the total P load to the river, while the mean annual internal load of NH4–N was determined to be 2066 Mg yr−1, 28% of the total N load to the LSJR estuary. As water resource managers reduce external loading to the LSJR the frequency of anaerobic events should decline, thereby reducing nutrient fluxes from the sediment to the water column, reducing the internal loading of DRP and NH4–N. Results from this study demonstrate that the internal flux of nutrients from sediments may be a significant portion of the total load and should be accounted for in the total nutrient budget of the river for successful restoration.
Modeling the Effects of Tillage Management Practices on Herbicide Runoff in Northern Italy
Authors: Miao Zewei , Vicari Alberto , Capri Ettore , Ventura Francesca , Padovani Laura , Trevisan Marco
Published: June 2010

The need to quantitatively predict pesticide runoff and erosion under cropping system management has gained increasing importance. In Europe, predictive models have not yet been fully validated because of the lack of field data sets. The objective of this study was to validate the capability of PRZM (Pesticide Root Zone Model) 3.12 to predict water runoff, sediment erosion, and associated transport of atrazine (6‐chloro‐N2–ethyl‐N4–isopropyl‐1,3,5‐triazine‐2,4‐diamine), terbuthylazine (N2–tert‐butyl‐6‐chloro‐N4–ethyl‐1,3,5‐triazine‐2,4‐diamine), and metolachlor [2‐chloro‐6′‐ethyl‐N‐(2‐methoxy‐l‐methylethyl)acet‐o‐toluidide] under common tillage management practices found in northern Italy. A 2‐yr field data set was used to evaluate the model. Results showed that the model could qualitatively simulate significant differences of water runoff, soil erosion, and associated herbicide losses between conventional tillage (CT) and minimum tillage (MT) for a winter barley (Hordeum vulgare L.) cover crop. For MT, water runoff, soil erosion, herbicide losses in water runoff and eroded sediment, and the proportion of herbicide loss via sediment erosion were significantly lower than for CT. The model failed to correctly simulate event‐based herbicide concentration, water runoff, and soil erosion. The model usually underestimated pesticide runoff events with high rainfall intensity and low daily precipitation volume, and overestimated runoff events with low intensity and high volume. The main reason was that the description of runoff and erosion processes is rather empirical in the model and not physically based. Moreover, model calculations do not adequately reflect the relationships between soil erosion intensity and chemical concentration in sediment losses, leading to discrepancies between predictions and field observations.
Interactions of Chlorpyrifos with Colloidal Materials in Aqueous Systems
Authors: Wu Jigang , Laird David A.
Published: June 2010

An understanding of sorptive processes is key to describing the fate of chlorpyrifos [O,O‐diethyl‐O‐(3, 5, 6‐trichloro‐2‐pyridyl) phosphorothioate] in aquatic environments. The objectives of this study were to evaluate isotherms for adsorption and desorption of chlorpyrifos on colloidal materials and to advance understanding of interaction mechanisms between chlorpyrifos and colloidal materials. Six Ca‐saturated reference smectites, one Ca‐saturated humic acid (Ca‐humate), and one suspended sediment sample, collected from the Upper Cedar River, Iowa, were studied. A batch equilibration technique was employed to quantify adsorption and desorption isotherms for chlorpyrifos over the 0 to 100 μg L−1 concentration range in a 0.01 M CaCl2 background. Large differences in sorption affinity and variation in desorption hysteresis were found among the smectites. Neither chlorpyrifos adsorption nor its desorption were correlated with cation exchange capacity, surface area, or surface charge density of the smectites. The evidence suggests that physical interaction between chlorpyrifos and smectites is the dominant mechanism for adsorption of chlorpyrifos in aqueous systems. Chlorpyrifos was very strongly sorbed on Ca‐humate and was not desorbed from the Ca‐humate back into the aqueous solution. Chlorpyrifos was moderately sorbed on river sediment, and a large adsorption–desorption hysteresis was also found. The study implies that the nature of both organic and inorganic materials in suspended sediment can influence the adsorption–desorption behavior of chlorpyrifos in aqueous systems.
Clonal Differences in Mercury Tolerance, Accumulation, and Distribution in Willow
Authors: Wang Yaodong , Greger Maria
Published: June 2010

This study was performed to investigate mercury (Hg) tolerance, accumulation, and translocation within the genus Salix for the potential use of this plant to remediate Hg‐contaminated sites. Six clones of willow (Salix spp.) were tested on tolerance to Hg by treating plants grown in solution culture with 0 to 15 μM HgCl2 Results showed that willow had a large variation in its sensitivity to Hg. However, the accumulation and translocation of Hg to shoots was similar in the eight tested willow clones as shown by cold vapor atomic absorption spectrometry analysis when plants were treated with 0.5 μM HgCl2 in a nutrient solution. The majority of total Hg accumulated was localized to the roots, whereas only 0.45 to 0.62% of the total Hg accumulated via roots was translocated to the shoots. Thus, the root system is the main tissue of willow that accumulates Hg and the majority of the Hg in the root system (80%) was bound in the cell wall.
Leaching and Crop Uptake of Nitrogen from Nitrogen‐15‐Labeled Green Manures and Ammonium Nitrate
Authors: Bergström Lars , Kirchmann Holger
Published: June 2010

Green manures can be used as an N source for agricultural crops as a substitute for inorganic N fertilizers. The effects of using green manures on leaching and uptake of N by spring barley (Hordeum vulgareL.) were evaluated in a 2‐yr lysimeter study. Ryegrass (Lolium perenneL.) and red clover (Trifolium pratenseL.) labeled with15N were applied in May of the first year at 160 kg total N ha−1Simultaneously,15NH415NO3was applied at 80 kg N ha−1to additional lysimeters and others were left without N additions (control). During the second year, all lysimeters, except the control, received 80 kg N ha−1as unlabeled NH4NO3The cumulative, average loads of total N leached during the two years were: 37 (control), 62 (NH4NO3), 50 (ryegrass manure), and 73 (red clover manure) kg ha−1The differences among the treatments were not significant (P> 0.05), but the control had significantly smaller (P< 0.05) leaching loads than the treatments. About 24% of ryegrass‐ and red clover–derived N and 43% of NH4NO3were removed through spring barley grain and stover during the two growing seasons. Thus, the N use efficiency in barley was substantially larger when grown with inorganic N fertilizer than when grown with green manure. Viewed in combination with the tendency for larger N leaching loads under red clover manure, claims about water quality benefits of legume‐based green manures should be evaluated with regard to the timing of N release and demand for N by the plant.
Relevance of Organic Matter Fractions as Predictors of Wastewater Sludge Mineralization in Soil
Authors: Parnaudeau Virginie , Nicolardot Bernard , Pagès Jérôme
Published: June 2010

Seventeen different wastewater sludges were characterized using both chemical and organic matter fractionation methods (water extraction, Van Soest method, and acid hydrolysis) and 6‐mo incubation studies to assess their decomposition in soil. Simple correlation and multiple factor analysis (MFA) were then performed to establish relationships between composition and C and N mineralization of sludges. Carbon and N concentrations covered a wide range of values, but organic carbon (Co) to organic nitrogen (No) ratios were relatively low (from 5 to 19). Carbon and N were mainly distributed in the most soluble fractions of the Van Soest method and in the water‐insoluble fraction at 100°C. Carbon mineralization varied from 180 to 661 g C kg−1organic C added during the 168‐d incubation. The addition of sludges led to different inorganic N dynamics: from −3.3 to +120.0 g N kg−1sludge organic C mineralized after the 168‐d incubation. Fractionation studies showed that the most discriminating method was acid hydrolysis. Carbon mineralization was linked with the proportion of sludge N and C present in the lignin‐like fraction (r= −0.68 and −0.65, respectively). Significant relationships were established between N mineralization and Noto Coratio (0.88 <r< 0.95) and the Coto Noratio of sludges, the C to N ratio of the soluble fraction obtained by the Van Soest method, the water‐soluble fraction at 100°C, and the C and N present in the acid‐hydrolyzable fraction. Finally, multiple factor analysis also enabled establishing a sludge typology using five clusters based on composition and mineralization characteristics.
The Effect of pH on Metal Accumulation in Two Alyssum Species
Authors: Kukier Urszula , Peters Carinne A. , Chaney Rufus L. , Angle J. Scott , Roseberg Richard J.
Published: June 2010

Nickel phytoextraction using hyperaccumulator plants offers a potential for profit while decontaminating soils. Although soil pH is considered a key factor in metal uptake by crops, little is known about soil pH effects on metal uptake by hyperaccumulator plants. Two Ni and Co hyperaccumulators, Alyssum murale and A. corsicum, were grown in Quarry muck (Terric Haplohemist) and Welland (Typic Epiaquoll) soils contaminated by a Ni refinery in Port Colborne, Ontario, Canada, and in the serpentine Brockman soil (Typic Xerochrepts) from Oregon, USA. Soils were acidified and limed to cover pH from strongly acidic to mildly alkaline. Alyssum grown in both industrially contaminated soils exhibited increased Ni concentration in shoots as soil pH increased despite a decrease in water‐soluble soil Ni, opposite to that seen with agricultural crop plants. A small decrease in Alyssum shoot Ni concentration as soil pH increased was observed in the serpentine soil. The highest fraction of total soil Ni was phytoextracted from Quarry muck (6.3%), followed by Welland (4.7%), and Brockman (0.84%). Maximum Ni phytoextraction was achieved at pH 7.3, 7.7, and 6.4 in the Quarry, Welland, and Brockman soils, respectively. Cobalt concentrations in shoots increased with soil pH increase in the Quarry muck, but decreased in the Welland soil. Plants extracted 1.71, 0.83, and 0.05% of the total soil Co from Welland, Quarry, and Brockman, respectively. The differences in uptake pattern of Ni and Co by Alyssum from different soils and pH were probably related to the differences in organic matter and iron contents of the soils.
Using Nitrogen‐15 to Quantify Vegetative Buffer Effectiveness for Sequestering Nitrogen in Runoff
Authors: Bedard‐Haughn A. , Tate K. W. , van Kessel C.
Published: June 2010

Previous studies have observed higher levels of soluble nutrients leaving vegetative buffers than entering them, suggesting that the buffers themselves are acting as a source rather than a sink by releasing previously stored nutrients. This study used 98 atom % 15N‐labeled KNO3 at a rate of 5 kg ha−1 to quantify buffer efficiency for sequestering new inputs of NO−3–N in an extensively grazed irrigated pasture system. Buffer treatments consisted of an 8‐m buffer, a 16‐m buffer, and a nonbuffered control. Regardless of the form of runoff N (NO−3, NH+4, or dissolved organic nitrogen [DON]), more 15N was lost from the nonbuffered treatments than from the buffered treatments. The majority of the N attenuation was by vegetative uptake. Over the course of the study, the 8‐m buffer decreased NO−3–15N load by 28% and the 16‐m buffer decreased load by 42%. For NH+4–15N, the decrease was 34 and 48%, and for DON–15N, the decrease was 21 and 9%. Although the buffers were effective overall, the majority of the buffer impact occurred in the first four weeks after 15N application, with the buffered plots attenuating nearly twice as much 15N as the nonbuffered plots. For the remainder of the study, buffer effect was not as marked; there was a steady release of 15N, particularly NO−3– and DON–15N, from the buffers into the runoff. This suggests that for buffers to be sustainable for N sequestration there is a need to manage buffer vegetation to maximize N demand and retention.
Effect of Root Death and Decay on Dissipation of Polycyclic Aromatic Hydrocarbons in the Rhizosphere of Yellow Sweet Clover and Tall Fescue
Authors: Parrish Zakia D. , Banks M. Katherine , Schwab A. Paul
Published: June 2010

A 12‐mo greenhouse study was conducted to evaluate the contribution of root death and decay on the dissipation of polycyclic aromatic hydrocarbons (PAHs) in rhizosphere soil. The contaminated soil was previously treated by land‐farming, but residual PAHs remained after treatment. Tall fescue (Festuca arundinacea Schreb.) and yellow sweet clover (Melilotus officinalis Lam.) were the target plants. To specifically evaluate the effect of root decay on contaminant dissipation, plants were treated with glyphosate, a broad spectrum herbicide, to induce root decay. Although tall fescue treatments had the highest root and shoot biomass and root surface area, this plant did not result in the highest contaminant degradation rates. Significant differences were noted between treatments for seven PAHs, with the active yellow sweet clover resulting in 60 to 75% degradation of these compounds. Induced root death and decay did not produce a significant enhancement of PAH degradation. The PAH microbial degrader populations in the vegetated treatments were more than 100 times greater than those in the unvegetated control. The phospholipid fatty acid (PLFA) structural group profile shifted over the growing period, indicating a change in the community structure. In conclusion, phytoremediation was shown to be an effective polishing tool for PAH‐affected soil previously subjected to biological treatment.
Characterizing Land Surface Erosion from Cesium‐137 Profiles in Lake and Reservoir Sediments
Authors: Zhang Xinbao , Walling Desmond E.
Published: June 2010

Recognition of the threat to the sustainable use of the earth's resources posed by soil erosion and associated off‐site sedimentation has generated an increasing need for reliable information on global rates of soil loss. Existing methods of assessing rates of soil loss across large areas possess many limitations and there is a need to explore alternative approaches to characterizing land surface erosion at the regional and global scale. The downcore profiles of 137Cs activity available for numerous lakes and reservoirs located in different areas of the world can be used to provide information on land surface erosion within the upstream catchments. The rate of decline of 137Cs activity toward the surface of the sediment deposited in a lake or reservoir can be used to estimate the rate of surface lowering associated with eroding areas within the upstream catchment, and the concentration of 137Cs in recently deposited sediment provides a basis for estimating the relative importance of surface and channel, gully, and/or subsurface erosion as a source of the deposited sediment. The approach has been tested using 137Cs data from several lakes and reservoirs in southern England and China, spanning a wide range of specific suspended sediment yield. The results obtained are consistent with other independent evidence of erosion rates and sediment sources within the lake and reservoir catchments and confirm the validity of the overall approach. The approach appears to offer valuable potential for characterizing land surface erosion, particularly in terms of its ability to provide information on the rate of surface lowering associated with the eroding areas, rather than an average rate of lowering for the entire catchment surface.
Cascading Ecological Effects of Low‐Level Phosphorus Enrichment in the Florida Everglades
Authors: Gaiser Evelyn E. , Trexler Joel C. , Richards Jennifer H. , Childers Daniel L. , Lee David , Edwards Adrienne L. , Scinto Leonard J. , Jayachandran Krish , Noe Gregory B. , Jones Ronald D.
Published: June 2010

Few studies have examined long‐term ecological effects of sustained low‐level nutrient enhancement on wetland biota. To determine sustained effects of phosphorus (P) addition on Everglades marshes we added P at low levels (5, 15, and 30 μg L−1 above ambient) for 5 yr to triplicate 100‐m flow‐through channels in pristine marsh. A cascade of ecological responses occurred in similar sequence among treatments. Although the rate of change increased with dosing level, treatments converged to similar enriched endpoints, characterized most notably by a doubling of plant biomass and elimination of native, calcareous periphyton mats. The full sequence of biological changes occurred without an increase in water total P concentration, which remained near ambient levels until Year 5. This study indicates that Everglades marshes have a near‐zero assimilative capacity for P without a state change, that ecosystem responses to enrichment accumulate over time, and that downstream P transport mainly occurs through biota rather than the water column.
A Shunt Power Conditioner Operated by a Simplified Version of the Gauss-Newton Algorithm
Authors: Alnadi Amr M , Liu Yanfei
Published: June 2010

This paper introduces a developed simplified version for the recursive Gauss-Newton algorithm for extraction and mitigation of the stationary current quality problems such as current harmonics and current fluctuation. Adaptive notch filters are newly utilized for supplying the Gauss-Newton algorithm with the required values of frequencies for current disturbances such as non-characteristic harmonics, inter-harmonics and sub-harmonics. Also, this paper exhibits the mitigation results for current harmonics and fluctuation problems by using a shunt power conditioner. Moreover, in this paper the ramp-comparison current controller, linear current controller, is employed to operate the mitigation device. The effectiveness of the developed extraction technique associated with the employed current controller for the shunt power conditioner is verified by simulation results using MATLAB/SIMULINK.
Costly Interference: A Game Theoretic Analysis of Sanctions
Authors: Langlois Catherine C , Langlois Jean-Pierre P.
Published: June 2010

Sanctions are often described as having two strikes against them: they are costly to the sanctioner, and they take time to achieve their goal, if they succeed at all. We argue in this paper that these are instead characteristics of rational sanctioning strategies. We view the sanctioning game as a subtle mix of bargaining and war of attrition. Our formal analysis shows that equilibrium behavior involves making one's opponent indifferent between accepting an ungenerous offer and continuing the struggle, a condition we call countervailing. Countervailing behavior implies that the costs incurred by the sanctioner correlate positively with the probability that the target will acquiesce to the sender's demands, and conversely. This insight runs counter to the conventional wisdom on the impact of costs in sanctioning episodes and suggests that policy makers think differently about the success or failure of sanctions.
Influences on Teacher Education Majors' Interpretations of Financial Morality
Authors: Lucey Thomas A. , Bates Alan B.
Published: June 2010

This article argues that narrow interpretations of financial literacy lack a valued moral component. Reviewing literature that defines financial literacy, morality, and financial morality, the authors present the results of a study that interpreted patterns of influence on agreement with financial morality. The study involved education majors at a public Midwest institution for higher learning. There were approximately 270 respondents. The study found that the set of variables significantly influenced only one of the subscales (identity issues). The authors call for additional research into this area that uses broader samples and which interprets relationships among other influential variables.
Voluntary Disclosure in Annual Reports: The Association between Magnitude and Direction of Change in Corporate Financial Performance and Graph Use
Authors: Dilla William N. , Janvrin Diane J.
Published: June 2010

SYNOPSIS: Prior archival research indicates that companies reporting increases in key financial performance variables (KFVs) are more likely to include graphs of these measures in their annual reports. This study expands prior work by using impression management and political cost theories to predict that the relationship between magnitude of KFV change and graphical disclosure differs, depending on whether the KFV is increasing or decreasing. Using data from 184 top U.S. companies that were in continual existence from 1999 to 2005, we replicate earlier findings that companies with increases in corporate performance are more likely to graph KFVs. Consistent with earlier theories of graphical disclosure, we find that companies with larger decreases in performance measures tend to be less likely to graph KFVs. At the same time, we extend prior research by showing that companies with larger increases in sales are more likely to graph these measures, but companies with larger increases in the “bottom line” measures of net income and earnings per share are less likely to graph KFVs. Our results indicate that the relationship between changes in corporate performance and graph usage is more complex than the simple directional relationships found in earlier research. These findings are consistent with impression management and political cost theories.
Role of interferon gamma release assay in the diagnosis of Pott disease
Authors: Kumar Raj , Das Rupant K. , Mahapatra Ashok Kumar
Published: June 2010

Object

Tuberculosis is ubiquitous in its presence and in its myriad manifestations. Despite several advances, it often poses a diagnostic dilemma. The aim of this study was to evaluate the efficacy of the QuantiFERON assay in the diagnosis of Pott disease.

Methods

In this study, 70 consecutive patients with vertebral collapse underwent a battery of investigations including radiological evaluation (MR imaging and chest and spine radiography), routine blood workup (hemoglobin, total leukocyte count, differential leukocyte count, and erythrocyte sedimentation rate), enzyme-linked immunosorbent assay (ELISA) for tuberculosis, a bone scan and the QuantiFERON assay, perioperative evaluation, and bacteriological studies. The patients were then classified as having tuberculosis on the basis of positive smear or culture, a biopsy consistent with tuberculosis, or a therapeutic response to antituberculosis chemotherapy on follow-up. The efficacy of the investigations, both individually and in combination, were evaluated.

Results

Tuberculosis was diagnosed in 51 patients, and 19 had vertebral collapse that was attributable to other causes. Based on the authors' data, sensitivity of the QuantiFERON assay in the diagnosis of tuberculosis of the spine was 84% and specificity was 95%. In combination with radiological criteria, bone scan, and ELISA, the QuantiFERON assay was predictive of tuberculosis in 90% of cases (46 patients).

Conclusions

None of the investigative modalities individually are efficacious enough to make a diagnosis of tuberculosis of the spine with such a degree of certainty as to to obviate the need for a tissue diagnosis or bacteriological confirmation. The ELISA, MR imaging of the spine, and bone scanning findings provide a reasonably certain diagnosis in 90% of cases, providing the grounds for starting a safe trial of antituberculous chemotherapy.
Refinements to the simultaneous anterior-posterior approach to the thoracolumbar spine
Authors: Peeling Lissa , Frangou Evan , Hentschel Stephen , Gokaslan Ziya L. , Fourney Daryl R.
Published: June 2010

The treatment of complex thoracolumbar disorders occasionally requires combined anterior and posterior approaches. Traditionally, these are either sequentially staged to occur during the same anesthesia procedure or alternatively performed on separate days. A less common option is the simultaneous anterior-posterior approach. The authors discuss the rationale for this approach in selected cases and illustrate a number of modifications to previous descriptions of the procedure. By slightly altering the incision, the risk of wound breakdown and infection has been reduced. The use of newly available positioning devices has allowed easy incorporation of fluoroscopy to guide the placement of spinal instrumentation. The authors have also expanded the use of the approach beyond the original oncological indications to include trauma and infection.
Comparison of patient and surgeon ratings of outcome 12 months after spine surgery
Authors: Porchet François , Lattig Friederike , Grob Dieter , Kleinstueck Frank S. , Jeszenszky Dezsö , Paus Christophe , O'Riordan David , Mannion Anne F.
Published: June 2010

Object

The contemporary assessment of spine surgical outcome primarily relies on patient-centered reports of symptoms and function. Such measures are considered to reduce bias compared with traditional surgeon-based outcome ratings. This study examined the agreement between patients' and surgeons' ratings of outcome 1 year after spine surgery.

Methods

The study involved 404 patients (mean age 56.6 ± 16.4 years; 259 women, 145 men) and their treating surgeons. At baseline and 12 months postoperatively patients completed the Core Outcome Measures Index (COMI) rating pain, function, quality of life, and disability. At 12 months postoperatively, they also rated the global outcome of surgery and their satisfaction with treatment. The surgeon, blinded to the patient's evaluation, rated the global outcome of surgery as excellent, good, fair, or poor.

Results

Seventy-six percent of the patients who were considered by the surgeon to have an excellent or good outcome achieved the minimum clinically important difference (MCID) of a 2.2-point reduction on the COMI; 24% achieved less than the MCID. There was a significant correlation between the surgeons' and patients' global outcome ratings (Spearman ρ = 0.56; p < 0.0001). The degree of absolute agreement between them was significantly influenced by surgeon seniority: senior surgeons “overrated” the outcome in 24.5% of cases (compared with patients' ratings) and “underrated” it in 17.5% of cases. Junior surgeons overrated in 7.8% of cases and underrated in 43.8% of cases (p < 0.0001). Surgeon overrating occurred significantly more frequently for patients with a poor self-rated outcome (measured as global outcome, COMI score, or satisfaction with treatment). In a multivariate model, the independent variables “senior surgeon” and “patient dissatisfaction with care” were the most significant unique predictors of surgeon overrating of the global outcome (p < 0.0001; adjusted R2for the model = 0.16).

Conclusions

Overall, agreement between surgeon and patient was reasonably good. The majority of patients who were rated as excellent/good by the surgeons had achieved the MCID in the prospectively measured COMI score. Discrepancies in outcome ratings were influenced by surgeon seniority and patient satisfaction. For a balanced view of the surgical result, outcomes should be assessed from the perspectives of both the patient and the surgeon.
Surgical excision of extensive sacrococcygeal chordomas assisted by occlusion of the abdominal aorta
Authors: Xue-Song Liu , Chao You , Kai-Yong Yang , Si-Qing Huang , Heng Zhang
Published: June 2010

Object

An extensive sacrococcygeal chordoma is considered a challenge for neurosurgeons. Because of the complex anatomy of the sacral region, the risk of uncontrollable intraoperative hemorrhage, and the typically large tumor size at presentation, complete resections are technically difficult and the tumor recurrence rate is high. The aim of this study was to assess the value of using occlusion of the abdominal aorta by means of a balloon dilation catheter and electrophysiological monitoring when an extensive sacrococcygeal chordoma is removed.

Methods

Between 2004 and 2008, 9 patients underwent resection of extensive sacrococcygeal chordomas in the authors' department with the aid of occlusion of the abdominal aorta and electrophysiological monitoring. All of these operations were performed via the posterior approach. The records of the 9 patients were reviewed retrospectively.

Results

Wide resections were performed in 6 cases and marginal excisions in the other 3. Five patients underwent postoperative radiotherapy. Intraoperative hemorrhage was controlled at 100–400 ml. Postoperatively, none of the patients had any new neurological dysfunction, and 2 patients regained normal urinary and bowel function. The mean follow-up period was 31.4 months (range 10–57 months). No patient developed local recurrence or had metastatic spread of tumor during follow-up.

Conclusions

Occlusion of the abdominal aorta and electrophysiological monitoring are useful methods for assisting in resection of sacrococcygeal chordoma. They can reduce intraoperative hemorrhage and entail little chance of tumor cell contamination. They can also help surgeons to protect the organs in the pelvic cavity and neurological function. Use of these methods could give patients better quality of life.
Inadequately Treated Wastewater as a Source of Human Enteric Viruses in the Environment
Authors: Okoh Anthony I. , Sibanda Thulani , Gusha Siyabulela S.
Published: June 2010

Human enteric viruses are causative agents in both developed and developing countries of many non-bacterial gastrointestinal tract infections, respiratory tract infections, conjunctivitis, hepatitis and other more serious infections with high morbidity and mortality in immunocompromised individuals such as meningitis, encephalitis and paralysis. Human enteric viruses infect and replicate in the gastrointestinal tract of their hosts and are released in large quantities in the stools of infected individuals. The discharge of inadequately treated sewage effluents is the most common source of enteric viral pathogens in aquatic environments. Due to the lack of correlation between the inactivation rates of bacterial indicators and viral pathogens, human adenoviruses have been proposed as a suitable index for the effective indication of viral contaminants in aquatic environments. This paper reviews the major genera of pathogenic human enteric viruses, their pathogenicity and epidemiology, as well as the role of wastewater effluents in their transmission.
In Response to: ‘Impact of Glycosylation on Effector Functions of Therapeutic IgG’ (Pharmaceuticals 2010, 3, 146–157)
Authors: Nechansky Andreas , Koller Iris , Kircheis Ralf
Published: June 2010

To complete the review article by Abes and colleagues (Pharmaceuticals 2010, 3, 146–157) which provides a good overview on recently developed approaches for generation of glyco-modified antibodies and the impact of glyco-modification of antibodies on their effector functions, important information should be added, namely that — besides the Glycart and the Biowa approach to generate de-fucosylated antibodies — innovative, moss derived methods have been shown to generate glyco-modified antibodies with improved effector function profile.
Assessment of Light Environment Variability in Broadleaved Forest Canopies Using Terrestrial Laser Scanning
Authors: Van der Zande Dimitry , Stuckens Jan , Verstraeten Willem W. , Muys Bart , Coppin Pol
Published: June 2010

Light availability inside a forest canopy is of key importance to many ecosystem processes, such as photosynthesis and transpiration. Assessment of light availability and within-canopy light variability enables a more detailed understanding of these biophysical processes. The changing light-vegetation interaction in a homogeneous oak (Quercus robur L.) stand was studied at different moments during the growth season using terrestrial laser scanning datasets and ray tracing technology. Three field campaigns were organized at regular time intervals (24 April 2008; 07 May 2008; 23 May 2008) to monitor the increase of foliage material. The laser scanning data was used to generate 3D representations of the forest stands, enabling structure feature extraction and light interception modeling, using the Voxel-Based Light Interception Model (VLIM). The VLIM is capable of estimating the relative light intensity or Percentage of Above Canopy Light (PACL) at any arbitrary point in the modeled crown space. This resulted in a detailed description of the dynamic light environments inside the canopy. Mean vertical light extinction profiles were calculated for the three time frames, showing significant differences in light attenuation by the canopy between April 24 on the one hand, and May 7 and May 23 on the other hand. The proposed methodology created the opportunity to link these within-canopy light distributions to the increasing amount of photosynthetically active leaf material and its distribution in the considered 3D space.
Exploring Infrared Sensoring for Real Time Welding Defects Monitoring in GTAW
Authors: Alfaro Sadek C. A. , Franco Fernand Díaz
Published: June 2010

This paper presents an evaluation of an infrared sensor for monitoring the welding pool temperature in a Gas Tungsten Arc Welding (GTAW) process. The purpose of the study is to develop a real time system control. It is known that the arc welding pool temperature is related to the weld penetration depth; therefore, by monitoring the temperature, the arc pool temperature and penetration depth are also monitored. Various experiments were performed; in some of them the current was varied and the temperature changes were registered, in others, defects were induced throughout the path of the weld bead for a fixed current. These simulated defects resulted in abrupt changes in the average temperature values, thus providing an indication of the presence of a defect. The data has been registered with an acquisition card. To identify defects in the samples under infrared emissions, the timing series were analyzed through graphics and statistic methods. The selection of this technique demonstrates the potential for infrared emission as a welding monitoring parameter sensor.
Effect of Antioxidant Mixtures on Growth and Ochratoxin A Production of Aspergillus Section Nigri Species under Different Water Activity Conditions on Peanut Meal Extract Agar
Authors: Barberis Carla , Astoreca Andrea , Fernandez-Juri María Guillermina , Dalcero Ana María , Magnoli Carina
Published: June 2010

The effect of mixtures of antioxidants butylated hydroxyanisol (BHA) and propyl paraben (PP) on lag phase, growth rate and ochratoxin A (OTA) production by four Aspergillus section Nigri strains was evaluated on peanut meal extract agar (PMEA) under different water activities (aw). The antioxidant mixtures used were: BHA + PP (mM), M1 (0.5 + 0.5), M2 (1.0 + 0.5), M3 (2.5 + 0.5), M4 (0.5 + 1.0), M5 (1.0 + 1.0), M6 (2.5 + 1.0), M7 (5.0 + 2.5) and M8 (10 + 2.5). The mixture M8 completely suppressed mycelial growth for all strains. A significant stimulation in OTA production was observed with mixtures M1 to M5 mainly at the highest aw; whereas M6, M7 and M8 completely inhibited OTA production in all strains assayed; except M6 in A. carbonarius strain (RCP G). These results could enable a future intervention strategy to minimize OTA contamination.
Historical Perspectives in the Development of Antiviral Agents Against Poxviruses
Authors: De Clercq Erik
Published: June 2010

The poxvirus vaccinia virus (VV) served as the model virus for which the first antivirals, the thiosemicarbazones, were identified. This dates back to 1950; and, although there is at present no single antiviral drug specifically licensed for the chemotherapy or -prophylaxis of poxvirus infections, numerous candidate compounds have been described over the past 50 years. These compounds include interferon and inducers thereof (i.e., polyacrylic acid), 5-substituted 2’-deoxyuridines (i.e., idoxuridine), IMP dehydrogenase inhibitors, S-adenosylhomocysteine hydrolase inhibitors, acyclic nucleoside phosphonates (such as cidofovir) and alkoxyalkyl prodrugs thereof (such as CMX001), viral egress inhibitors (such as tecovirimat), and cellular kinase inhibitors (such as imatinib).
The Relationship Between Recreation Experience Preferences and Revealed Activity Choice in the North Shore Lake Superior Region
Authors: Yuan Michael , Fredman Peter
Published: June 2010

Planning for tourism in rural regions necessitates much information about the visitor. The goal of most planning efforts is to understand visitor expectations and predict participation patterns. When demand is understood, the provision of appropriate supply can be more effective and
efficient. This study examined the degree to which the experience preference–activity relationship holds for the three primary target market groups (Northwest Ontario, rest of Canada, US) to the Ontario North Shore Lake Superior region. For this study, 464 visitors who engaged in activities
along Lake Superior or related activities in the communities and land adjacent to the water were used in the analysis. The results suggest that there is a weak relationship between experience preference and activity choice, but when results are examined by more defined market segments, some
moderate relationships appear. This suggests that associated promotion and advertising in the region should focus its message and images based on these significant relationships.
PLATE GIRDERS WITH CORRUGATED WEBS
Authors: Pasternak Hartmut , Kubieniec Gabriel
Published: June 2010

Especially for the main frames of single‐storey steel buildings the use of corrugated web beams, mainly with sinusoidal corrugation, has been increased very much during the last years. Due to the thin web of 1,5 mm to 3 mm corrugated web beams afford a significant weight reduction compared with hot rolled profiles or welded I‐sections. Buckling failure of the web is prevented by the corrugation. The buckling resistance of presently used sinusoidal corrugated webs is comparable with plane webs of 12 mm thickness or more. Due to improvements of the automatic fabrication process corrugated webs up to 6 mm thickness became possible. Therefore the field of application of this beam type has been extended considerable. Even short span bridges are possible now. The dimensioning of corrugated web beams is ruled by the EN 1993–1‐5 Annex D ‐ it covers only web thicknesses up to 3 mm. In the last years many tests and finite element simulations have been carried out. Regarding this background, these EN rules will be discussed and extended. Furthermore, additional proposals for patch loading and lateral‐torsional buckling of girders with sinussoidal webs will be given.

Santrauka

Pastaruoju metu ypač vienaukščiu pastatu plieniniams remams imtos plačiai naudoti sijos su pagal sinusoide banguota sienele. Del plonu 1,5–3,0 mm storio gofruotuju siju sieneliu ju mase gerokai sumažeja, palyginti su karštai valcuotomis arba virintinemis dvitejo skerspjūvio sijomis. Sijos sieneles klumpamosios irties išvengiama del sieneles bangavimo. Šiuo metu naudojamu pagal sinusoide subanguotu sieneliu klumpamoji galia yra lygintina su 12 mm arba didesnio storio plokščiu sieneliu galia. Patobulinus automatini gaminimo procesa gofruotaja sienele galima padaryti iki 6 mm storio. Todel labai išsiplečia šiu siju naudojimo sritys. Sijos gali būti naudojamos nedidelio tarpatramio tiltams. Banguotasieniu siju projek‐tavimo metodika aprašyta EN 1993–1‐5 D priede, tačiau ji galioja tik sijoms, kuriu sieneles storis neviršija 3 mm. Pastarai‐siais metais atlikta daug bandymu ir skaitiniu eksperimentu baigtiniu elementu metodu. Todel šios EN projektavimo nuostatos bus aptariamos ir išplestos. Be to, straipsnyje pateiktos papildomos rekomendacijos, kaip vertinti siju su pagal sinusoide banguota sienele uždetaja apkrova ir lenkiamaji sukamaji klupuma.
THE QUASI-DUCTILE RESISTANCE OF COMPRESSED SPUN CONCRETE BEAM‐COLUMNS
Authors: Kliukas Romualdas , Kudzys Antanas , Vadlūga Romualdas
Published: June 2010

The expediency of reinforcing precast spun concrete members of annular cross sections reinforced by high‐strength steel bars is discussed. Test materials, mechanical properties, production and testing procedures of plain and rein‐forced spun concrete specimens are presented. The quasi‐ductile strength and strain features of concentrically and eccentrically loaded specimens are considered. The modelling of a bearing capacity of beam‐columns of annular cross sections is based on the concepts of bending with a concentrical force and compression with a bending moment. The comparison of modelling and test data of spun concrete beam‐columns is analysed. Santrauka Aptariamas didžiastipriais plieniniais strypais armuotu gamykliniu žiedinio skerspjūvio elementu iš centrifuguotojo betono tinkamumas. Pateiktos grynojo ir armuotojo centrifuguotojo betono bandiniu medžiagos, mechanines savybes, gamybos ir bandymo tvarka. Nagrinejamos centriškai ir ekscentriškai apkrautu bandiniu tartum stamantraus stiprumo ir deformaciju ypatybes. Žiedinio skerspjūvio sijiniu kolonu laikomajai galiai modeliuoti taikomos gniuždomojo lenkimo ir lenkiamojo gniuždymo sampratos. Analizuojami sijiniu kolonu iš centrifuguotojo betono modeliavimo ir bandymo duomenys.