bluuebunny/crossref_metadata_2025 huggingface dataset:
Challenges and Options for Patient Education in the Office Setting
Authors: D'Alessandro Donna M.
Published: February 2010

CME EDUCATIONAL OBJECTIVES

1.

Delineate challenges to successful patient and family health education delivery in the office setting.

2.

Determine the deleterious effects of inadequate attention to health literacy and illuminate methods currently used by patients to empower themselves in health decision-making.

3.

Provide educational options to assist in partnering with patients and families to successfully deliver timely, effective, and useful education.
Primary Care Physicians and Hospitalists: Two Branches of the Same Tree
Authors: Seelbach Elizabeth Berry , Ottolini Mary C.
Published: February 2010

CME EDUCATIONAL OBJECTIVES

1.

Describe the evolution of the practice of pediatric hospitalist medicine as a defined field.

2.

Assess the importance of communication between the primary care provider and the pediatric hospitalist and highlight the effect timely and ongoing communication can have on the quality of patient care delivered in the hospital as well as after discharge.

3.

Illuminate the role currently played by pediatric hospitalists in residency and medical student education and the need to plan for future training of pediatric house staff.
Attempting to Meet Our Nation's Pediatric Workforce Needs
Authors: Shipman Scott A.
Published: February 2010

CME EDUCATIONAL OBJECTIVES

1.

Discuss the effect of increased sub-specialization and the expansion of non-physician clinicians on the role of the primary care pediatrician.

2.

Delineate changes in the general pediatric workforce, with emphasis on changes in gender balance, geographic distribution, part-time practice, and workforce diversity.

3.

Determine the opportunities available to pediatric training programs in shaping the role of the primary care generalist.
INTACS Followed by KeraRing Intrastromal Corneal Ring Segment Implantation for Keratoconus
Authors: Coskunseven Efekan , Kymionis George D. , Grentzelos Michael A. , Karavitaki Alexandra E. , Portaliou Dimitra M. , Jankov Mirko R. , Arslan Ebru
Published: February 2010

PURPOSE:

To describe the visual and refractive outcomes in three eyes (two keratoconic patients) with previous intrastromal corneal ring segments (INTACS, Addition Technology Inc) that underwent adjuvant single KeraRing (Mediphacos) intrastromal corneal ring segment implantation.

METHODS:

Two keratoconic patients (three eyes) with implanted INTACS segments underwent an additional (without explanting previous INTACS) single KeraRing segment implantation.

RESULTS:

No intraoperative complications occurred. Six months postoperatively, uncorrected distance visual acuity improved from 20/100 and 20/200 to 20/32 and 20/40 in the right and left eyes, respectively, of patient 1, and from 20/400 to 20/50 in the treated right eye of patient 2. Corrected distance visual acuity improved from 20/50 and 20/100 to 20/30 and 20/32 in the right and left eyes, respectively, of patient 1 and from 20/200 to 20/40 in patient 2. Keratometric measurements improved from 51.00/45.70 to 47.00/44.60 diopters (D) and from 50.80/48.80 to 42.70/40.30 D in the right and left eyes, respectively, of patient 1, and from 49.30/45.70 to 45.60/44.10 D in patient 2.

CONCLUSIONS:

In keratoconic patients with INTACS in place, adjuvant single intrastromal corneal ring segment (KeraRing) implantation could improve visual and refractive outcome. [
J Refract Surg
. 2010;26:371–374.]
Effect of Pupil Size on Visual Acuity in a Laboratory Model of Pseudophakic Monovision
Authors: Kawamorita Takushi , Uozato Hiroshi , Handa Tomoya , Ito Misae , Shimizu Kimiya
Published: February 2010

PURPOSE:

To investigate the effect of pupil size on visual acuity in pseudophakic monovision.

METHODS:

For the simulation, a modified Liou-Brennan model eye was used. The model eye was designed to include a centered optical system, corneal asphericity, an iris pupil, a Stiles–Crawford effect, an intraocular lens, and chromatic aberration. Calculation of the modulation transfer function (MTF) was performed with ZEMAX software. Visual acuity was estimated from the MTF and the retinal threshold curve. The sizes of the entrance pupil were 2.0, 2.5, 3.0, and 4.0 mm.

RESULTS:

Decreasing pupil diameter and increasing myopia progressively improved near visual acuity. For an entrance pupil size of 2.5 mm and a refractive error of −1.50 diopters, the logMAR value (Snellen; metric) in the non-dominant eye at 40 cm was 0.06 (20/23; 6/6.9).

CONCLUSIONS:

Knowledge of the patient's pupil diameter at near fixation can assist surgeons in determining the optimum degree of myopia for successful monovision. [
J Refract Surg.
2010;26:378–380.]
Corneal Spherical Aberration of Eyes with Cataract in a Japanese Population
Authors: Shimozono Masataka , Uemura Akiyoshi , Hirami Yasuhiko , Ishida Kazuhiro , Kurimoto Yasuo
Published: February 2010

Purpose:

To investigate the distribution of corneal spherical aberration in Japanese eyes with cataract for implantation of aspheric intraocular lenses (IOLs).

Methods:

Corneal spherical aberration (Zernike coefficient

Z
4
0

) in the central 6-mm zone was measured with a wavefront analyzer (KR9000PW, Topcon) in 257 eyes of 168 Japanese patients with cataract. Axial length was also measured for each eye.

Results:

Mean corneal spherical aberration was 0.203±0.100 μm (range: −0.103 to 0.497 μm). A significant negative correlation was found between axial length and corneal spherical aberration (r=−0.135,
P
=.036).

Conclusions:

Corneal spherical aberration varied among cataract patients and correlated with axial length. Japanese patients showed a relatively smaller corneal spherical aberration than previous studies of Caucasians. Preoperative measurement of wavefront aberrations is thus important in using aspheric IOLs.
Treatment of Highly Aberrated Eyes Using the NIDEK CXIII Excimer Laser
Authors: Gatinel Damien , Bains Harkaran S.
Published: February 2010

Purpose:

To describe the treatment of highly aberrated eyes due to previous excimer laser surgery or trauma.

Methods:

Three eyes (three patients) with reduced visual quality due to previous decentration or corneal laceration (one eye) underwent topography-guided ablation using the CXIII excimer laser (NIDEK Co Ltd) to correct residual refractive error and/or wavefront aberrations.

Results:

Postoperatively, one patient had a one-line increase in corrected distance visual acuity (CDVA) with a reduction in visual symptoms. At 2 months postoperatively, one patient maintained CDVA, increased uncorrected distance visual acuity from 20/20 to 20/15, and reported resolution of monocular diplopia. In all cases, the functional optical zone increased and wavefront aberrations decreased with selective flattening of the intended corneal region.

Conclusions:

Topography-guided ablation is an effective treatment of severe corneal aberrations due to surgery or trauma and can be selectively used to treat higher order aberrations with or without refractive error.
Effect of Topical 0.5% Morphine on Postoperative Pain After Photorefractive Keratectomy
Authors: Faktorovich Ella G. , Basbaum Allan I.
Published: February 2010

Purpose:

To investigate safety and efficacy of 0.5% morphine drops for pain control after photorefractive keratectomy (PRK).

Methods:

In a double-blind prospective study, 40 patients were randomized to either 0.5% morphine drops (n=20) or vehicle control (n=20). Treatment occurred every 2 hours following PRK on the day of the procedure, then four times daily on postoperative days 1 through 3. Patients completed pain assessment questionnaires (visual descriptor, numerical rating, visual analog scales, and oral analgesic consumption) every 2 hours while awake during the treatment period. Daily average and maximum scores were compared between the two groups. Patients were examined daily for 4 days after PRK, weekly for 4 weeks, then monthly for 3 months. Epithelial healing, corneal haze, and refractive outcomes were compared.

Results:

Both average and maximum pain scores were lower in the morphine group than in the vehicle control group on all scales and during all 4 days after PRK. Statistical significance (
P
<.05) was reached on numeric rating scale on procedure day and on postoperative day 1. The difference between the groups on the visual analog scale was statistically significant on procedure day, and on postoperative days 1 and 2. Oral analgesic consumption was higher in the vehicle control group on postoperative day 2. No difference between groups was noted in epithelial healing or refractive outcomes. Stromal haze scores were lower in the morphine group, but the difference was not statistically significant.

Conclusions:

Topical 0.5% morphine may be an effective and safe method of pain control after PRK.
Structural and dynamic properties of SPC/E water
Authors: Campo M. G.
Published: February 2010

I have investigated the structural and dynamic properties of water by performing a series of molecular dynamic simulations in the range of temperatures from 213 K to 360 K, using the Simple Point Charge-Extended (SPC/E) model. I performed isobaric-isothermal simulations (1 bar) of 1185 water molecules  using the GROMACS package. I quantified the structural properties using the oxygen-oxygen radial distribution functions, order parameters, and the hydrogen bond distribution functions, whereas, to analyze the dynamic properties I studied the behavior of the history-dependent bond correlation functions and the non-Gaussian parameter $\alpha_{2}(t)$ of the mean square displacement of water molecules. When the temperature decreases, the translational ($\tau$) and orientational ($Q$) order parameters are linearly correlated, and both increase indicating an increasing structural order in the systems. The probability of occurrence of four hydrogen bonds and $Q$ both have a reciprocal dependence with $T$, though the analysis of the hydrogen bond distributions permits to describe the changes in the dynamics and structure of water more reliably. Thus, an increase on the caging effect and the occurrence of long-time hydrogen bonds occur below $\sim$ 293 K, in the range of temperatures in which predominates a four hydrogen bond structure in the system.Received: 13 July 2009, Revised: 29 December 2009, Accepted: 7 February 2010; Edited by: S. A. Cannas; Reviewed by: P. Netz, Inst. de Química, Univ. Federal do Rio Grande do Sul, Brazil; DOI: 10.4279/PIP.020001
The Immunohistochemical Characterization of Human Fetal Olfactory Bulb and Olfactory Ensheathing Cells in Culture as a Source for Clinical CNS Restoration
Authors: Liu Kai , Li Ying , Wang Hongmei , Jiang Xiaorong , Zhao Yanting , Sun Dongming , Chen Lin , Young Wise , Huang Hongyun , Zhou Changman
Published: February 2010

Triple florescence labeling of human fetal olfactory ensheathing cells in culture under confocal microscopy. Red: p75, Green: GFAP, Blue: hoechest. In this issue, by Liu et al., on page 359.
Development of a zebrafish embryo teratogenicity assay and quantitative prediction model
Authors: Brannen Kimberly C. , Panzica‐Kelly Julieta M. , Danberry Tracy L. , Augustine‐Rauch Karen A.
Published: February 2010

BACKGROUND: A zebrafish (Danio rerio) teratogenicity assay has been developed and evaluated for its ability to predict the teratogenic potential of chemicals. METHODS: Zebrafish embryos were dechorionated and then exposed to a test solution from 4–6 hours post‐fertilization, and embryos or larvae were assessed up to 5 days post‐fertilization (dpf) for viability and morphology. In preliminary experiments, the potential time points for assessment of compound‐induced dysmorphology and general toxicity parameters were evaluated, and 5 dpf was found to be the optimum developmental stage for evaluation. Additionally, a morphological scoring system was devised to identify the developmental no‐observed‐adverse‐effect level (NOAEL). For assay evaluation, 34 compounds with adequate in vivo developmental toxicity data were chosen. The compound set represented diversity in teratogenic potencies, structural classes, and pharmacologic targets. For 31 test compounds, each was evaluated over a concentration range, while 3 others were insufficiently aqueous‐soluble to be fully tested. For each of the 31 tested compounds, the 5 dpf NOAEL was determined, and the concentration resulting in 25% lethality (LC25) was calculated by curve‐fitting. Teratogenic potential of each compound was predicted based on the ratio of the LC25 to the NOAEL. LC25/NOAEL ratios of 10 or greater were considered predictive of teratogenicity. RESULTS: The model successfully categorized 87% of the compounds as teratogens or non‐teratogens, with only 2 false‐positives (dimethyl phthalate and a Bristol‐Myers Squibb (BMS) investigative compound) and 2 false‐negatives (valproic acid and a BMS compound). CONCLUSIONS: The results indicate that this assay is promising for screening compounds for teratogenic potential. Birth Defects Res (Part B) 89:66–77, 2010. © 2010 Wiley‐Liss, Inc.
Malignant risk and surgical outcomes of presacral tailgut cysts
Authors: Mathis K L , Dozois E J , Grewal M S , Metzger P , Larson D W , Devine R M
Published: February 2010

Background

Presacral tailgut cysts are uncommon and few data exist on the outcomes following surgery.

Methods

Patients undergoing tailgut cyst resection at the Mayo Clinic between 1985 and 2008 were analysed retrospectively. Demographic data, clinicopathological features, operative details, postoperative complications and recurrence were reviewed.

Results

Thirty-one patients were identified (28 women), with a median age of 52 years. Seventeen patients were symptomatic and 28 had a palpable mass on digital rectal examination. Median cyst diameter was 4·4 cm. Four patients had a fistula to the rectum. Complete cyst excision was achieved in all patients; eight underwent distal sacral resection or coccygectomy. Postoperative complications occurred in eight patients but without 30-day mortality. Malignant transformation was present in four patients: adenocarcinoma in three and carcinoid in one. The cyst recurred in one patient after surgery for a benign lesion.

Conclusion

Presacral tailgut cysts should be removed due to the risk of malignant transformation.
Physical and Chemical Lipase Adsorption on SBA‐15: Effect of Different Interactions on Enzyme Loading and Catalytic Performance
Authors: Salis Andrea , Casula Maria F. , Bhattacharyya Mani S. , Pinna Marcella , Solinas Vincenzo , Monduzzi Maura
Published: February 2010

Immobilization of Pseudomonas fluorescens lipase (Pfl) on the chemically modified, or unmodified, surface of SBA‐15 mesoporous silica has been achieved. X‐ray diffraction (XRD), transmission electron microscopy (TEM), and N2 physisorption are used to monitor the effect of surface functionalization on the structural and textural features of the SBA‐15 silica support. The enzyme loading strongly depends on the type of enzyme–support interaction, the maximal loading of the chemisorbed lipase being about twice that of the physisorbed (502 and 256 mgprotein ${{\rm g}{{- 1\hfill \atop {\rm support}\hfill}}}$ respectively). The resulting biocatalysts, regardless of the different loading, are tested with a hydrolytic catalytic assay. Despite the lower loading, the physically immobilized Pfl is more active than that which is chemically immobilized. Both biocatalysts are also active in a green process for biodiesel production, leading to almost full conversion of sunflower oil and ethanol into the corresponding ethyl esters after about 7 h at 30 °C, atmospheric pressure, and in solvent‐free conditions. Recycling experiments showed that the chemically immobilized Pfl was still active after twenty reaction cycles whereas the physically immobilized Pfl lost its activity after the tenth cycle.
Interpretation of partial least squares regression models by means of target projection and selectivity ratio plots
Authors: Kvalheim Olav M.
Published: February 2010

Displays of latent variable regression models in variable and object space are provided to reveal model parameters useful for interpretation and to reveal the most influential x‐variables with respect to the predicted response. Although the target projected (TP) component obtained from a standard partial least square, or equivalently, the predictive component from orthogonal partial least squares (OPLS) or partial least squares + similarity transform (PLS + ST) is maximally co‐varying with the response, the corresponding loadings are not necessarily the best choice for model interpretation and disclosure of the most important variables with respect to explaining the response. Selectivity ratio plot represents a bridge from co‐variance‐based TP loadings to correlation‐like localized information suitable for interpretation. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of Sludge Retention Time on Nitrifiers' Biomass and Kinetics in an Anaerobic/Oxic Process
Authors: Pai Tzu‐Yi , Wan Terng‐Jou , Tsai Yung‐Pin , Tzeng Chwen‐Jeng , Chu Hsiao‐Hsing , Tsai Yao‐Sheng , Lin Ching‐Yuan
Published: February 2010

In this study, the effect of sludge retention time on ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in an anaerobic/oxic (AO) process, was explored. The results indicated that the growth rate constants of AOB were 0.97, 0.88, and 0.79 d–1, respectively, meanwhile, those of NOB were 1.22, 1.03, and 0.93 d–1, respectively, when the sludge retention time (SRT) was 15 days, 10 days and 5 days. The relation between the growth rate constant and the SRT could be best described using a simple exponential curve and a second type hyperbolic curve. The lysis rate constants for AOB and NOB were 0.13 and 0.18 d–1, respectively. The yield coefficients values of AOB and NOB were 0.22 and 0.21, respectively. The percentage of AOB to mixed liquid suspended solids (MLSS) was 0.64%, 0.53%, and 0.35%, respectively. Meanwhile, the percentage of NOB was 2.24%, 1.87%, and 1.11%, respectively, at SRT values of 15 days, 10 days and 5 days. When the SRT value decreased, the AOB and NOB biomass levels decreased by 12.75 and 47.01 mg L–1, respectively. Meanwhile the removal efficiency of NH4+‐N decreased from 90 to 26%, while the removal efficiency of total nitrogen (TN) decreased from 14 to 8%.
Use, misuse, and abuse of apparent diffusion coefficients
Authors: Grebenkov Denis S.
Published: February 2010

The notion of effective, time‐dependent or, equivalently, apparent diffusion coefficient (ADC) and its use for characterization of porous media are revisited. It is argued that the dynamic ADC, quantifying the mean‐square displacement of spin‐bearing particles, should not be confused with its counterpart measured by a pulsed gradient spin echo technique. The former is an intrinsic characteristic of the medium, independent of the applied magnetic field. In contrast, the spin‐echo ADC depends on the experimental setup (e.g., gradient intensity and temporal profile), raising potential ambiguities in the interpretation of diffusion‐weighted measurements, which may be strongly misleading when the Gaussian phase approximation (GPA) does not hold. The oversimplified use of a single b‐value is criticized. Several fitting models beyond the GPA are discussed. © 2010 Wiley Periodicals, Inc. Concepts Magn Reson Part A 36A: 24–35, 2010.
A simple wide‐band gradiometer for operation in very low background field
Authors: Bidinosti C.P. , Xian Z. , Hayden M.E.
Published: February 2010

A simple gradiometer, capable of sensing submicrotesla changes in magnetic field with 10‐μs resolution, is constructed from a pair of low‐cost, wide‐band Hall‐effect sensors output to a voltage preamplifier and digital storage oscilloscope. The linear operational range of the sensors (±7.5 mT) limits typical applications, such as gradient coil development and testing, to environments where background fields are very low. The gradiometer is ideal for characterizing gradient field rise times and waveforms in this limit and applications pertinent to very‐low‐field nuclear magnetic resonance and magnetic resonance imaging are presented. © 2010 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 37B: 1–6, 2010
Comparison of fatty acid profiles and mid‐infrared spectral data for classification of olive oils
Authors: Gurdeniz Gozde , Ozen Banu , Tokatli Figen
Published: February 2010

The composition of olive oils may vary depending on environmental and technological factors. Fatty acid profiles and Fourier‐transform infrared (FT‐IR) spectroscopy data in combination with chemometric methods were used to classify extra‐virgin olive oils according to geographical origin and harvest year. Oils were obtained from 30 different areas of northern and southern parts of the Aegean Region of Turkey for two consecutive harvest years. Fatty acid composition data analyzed with principal component analysis was more successful in distinguishing northern olive oil samples from southern samples compared to spectral data. Both methods have the ability to differentiate olive oil samples with respect to harvest year. Partial least squares (PLS) analysis was also applied to detect a correlation between fatty acid profile and spectral data. Correlation coefficients (R2) of a calibration set for stearic, oleic, linoleic, arachidic and linolenic acids were determined as 0.83, 0.97, 0.97, 0.83 and 0.69, respectively. Fatty acid profiles were very effective in classification of oils with respect to geographic origin and harvest year. On the other hand, FT‐IR spectra in combination with PLS could be a useful and rapid tool for the determination of some of the fatty acids of olive oils.
Probing Phosphane‐Mediated [2+1] Annulation Reactions
Authors: Liu Xu‐Guang , Wei Yin , Shi Min
Published: February 2010

Phosphane‐mediated cyclizations between α‐keto nitriles and methylidenemalononitriles, producing highly functionalized cyclopropanes in good to excellent yields, are reported. The presence of strongly electron‐withdrawing cyano groups directly bound to the ketone carbonyl groups is believed to play a critical role in these transformations.
CE detection of N‐(3‐dimethylaminopropyl)‐N‐carbodiimide/N‐hydroxysuccinimide‐coupled proteins after homo‐ and hetero‐crosslinking reactions
Authors: Muskotál Adél , Kokol Vanja
Published: February 2010

Protein–protein conjugates formed by carbodiimide crosslinking reactions have been analyzed for the first time using CE. Lysozyme and BSA were chosen as model proteins to study the efficacy of N‐(3‐dimethylaminopropyl)‐N‐ethylcarbodiimide and N‐hydroxysuccinimide as crosslinkers. Detection of the molecular mass increase was checked by SDS‐PAGE. Commercially available, PVA‐coated capillaries showed appropriate selection, while phospho‐deactivated and dynamic PVA‐coated capillaries did not give suitable resolution. CE was found to be an efficient tool to characterize homo‐ (lysozyme–lysozyme) and hetero‐ (lysozyme–BSA) protein coupling by suitable variations of electrophoretic mobilities.
Optimization of culture conditions for glucose oxidase production by a Penicillium chrysogenum SRT 19 strain
Authors: Bodade Ragini G. , Khobragade Chandarahas N. , Arfeen Saiful
Published: February 2010

The enzyme glucose oxidase (GOD) has been used for a variety of biotechnological applications in food and pharmaceutical industries. In this study, the optimization of extracellular GOD production was carried out in a Penicillium chrysogenum SRT 19 strain isolated from contaminated and decaying cheese samples. Maximum GOD production was attained at pH 6 and 20°C in fermentation broth after 72 h of incubation. The effects of metal ions and sugars were screened for the induction of higher GOD production. The results revealed that glucose and lactose give the highest production of enzyme (0.670 and 0.552 U/mL, respectively) as compared with other sugars (sucrose, cellulose, mannitol and fructose). Out of the seven metal ions studied, CaCO3 (1.123 U/mL) and FeSO4 (0.822 U/mL) act as modulators, while MgSO4 (0.535 U/mL), CuSO4 (0.498 U/mL), HgCl2 (0.476 U/mL), ZnSO4 (0.457 U/mL) and BaSO4 (0.422 U/mL) yield lower production. The study therefore suggests that a strain of P. chrysogenum SRT 19 can be used as a new strain for GOD production.
Effect of aluminum on cellular division and photosynthetic electron transport in Euglena gracilis and Chlamydomonas acidophila
Authors: Perreault François , Dewez David , Fortin Claude , Juneau Philippe , Diallo Amirou , Popovic Radovan
Published: February 2010

The present study investigated aluminum's effect on cellular division and the photosynthetic processes in Euglena gracilis and Chlamydomonas acidophila at pH 3.0, at which Al is present mostly as Al3+, AlSO 4+, and Al(SO4) 2−. These algal species were exposed to 100, 188, and 740 µM Al, and after 24 h cell-bound Al was significantly different from control only for the highest concentration tested. However, very different effects of Al on algal cellular division, biomass per cell, and photosynthetic activity were found. Aluminum stimulated cell division but decreased at some level biomass per cell in C. acidophila. Primary photochemistry of photosynthesis, as Photosystem II quantum yield, and energy dissipation via nonphotochemical activity were slightly affected. However, for E. gracilis, under the same conditions, Al did not show a stimulating effect on cellular division or photosynthetic activity. Primary photochemical activity was diminished, and energy dissipation via nonphotochemical pathways was strongly increased. Therefore, when Al is highly available in aquatic ecosystems, these effects may indicate very different response mechanisms that are dependent on algal species. Environ. Toxicol. Chem. 2010;29:887–892. © 2009 SETAC
Investigating the link between pulp mill effluent and endocrine disruption: Attempts to explain the presence of intersex fish in the Wabigoon River, Ontario, Canada
Authors: Pollock Michael S. , Dubé Monique G. , Schryer Richard
Published: February 2010

The ability of some pulp mill effluents (PME) to act as reproductive and endocrine disrupters in fish is well documented in the literature. However, changes are not always consistent with regard to species, gender, hormones, or reproductive effects. In the present study, the presence of the first intersexed fish that, to our knowledge, has been found in a Canadian river exposed to PME, is reported. A field survey of the Wabigoon River near Dryden, Ontario, in the fall of 2000 found intersexed walleye (Sander vitreus vitreus) with significantly altered hormone levels and reduced gonad size. The Wabigoon River receives discharge from a bleached kraft pulp and paper mill and a municipal wastewater (MWW) plant. It also has historical sediment contamination (wood fiber mats) contributing to extended periods of low dissolved oxygen under low flow, drought conditions. A mesocosm-based partial life cycle test exposing fathead minnows (Pimephales promelas) to reference water, 20% effluent volume to river volume (v/v), 40% (v/v), or 60% (v/v) PME as well as a field survey of the walleye in the Wabigoon River were conducted. The only change in our mesocosm exposure was a decrease in testosterone in males with increasing effluent concentration and vitellogenin induction in males exposed to 60% (v/v) effluent. These results did not reflect the magnitude of endocrine disruption seen in the wild fish survey. Several hypotheses that may explain these discrepancies are proposed. Specifically, evidence is offered from published studies indicating that either hypoxia or MWW, alone or in combination with PME, may explain the discrepancy between our field experiment and the wild fish survey. The present study illustrates the complexities of multistressor receiving environments and the need for the development of cumulative effects assessment approaches. Environ. Toxicol. Chem. 2010;29:952–965. © 2010 SETAC
Application of a congener-specific debromination model to study photodebromination, anaerobic microbial debromination, and FE0 reduction of polybrominated diphenyl ethers
Authors: Zeng Xia , Massey Simonich Staci L. , Robrock Kristin R. , Korytár Peter , Alvarez-Cohen Lisa , Barofsky Douglas F.
Published: February 2010

A model was used to predict the photodebromination of the BDE-203, 197, 196, and 153, the major components of the octa-polybrominated diphenyl ether (PBDE) technical mixture, as well as BDE-47, and the predicted results were compared to the experimental results. The predicted reaction time profiles of the photodebromination products correlate well with the experimental results. In addition, the slope of the linear regression between the measured product concentrations of the first step of the photodebromination products and their enthalpies of formation was found to be close to their theoretical value. The photodebromination results of the octa-BDE technical mixture were compared with anaerobic microbial debromination results and were found to be the same in both experiments. The debromination pathways of technical octa-BDE mixture were identified and BDE-154, 99, 47, and 31 were found to be the most abundant hexa-, penta-, tetra-, and tri-BDE debromination products, respectively. In addition to photodebromination and anaerobic biodebromination, the model prediction was also compared to the zero-valent iron reduction of BDE-209, 100, and 47 and the same debromination products were observed. Good correlation was observed between the photodebromination rate constants of fifteen PBDE congeners and their calculated lowest unoccupied molecular orbital (LUMO) energies, indicating that PBDE photodebromination is caused by electron transfer. Furthermore, the rate constants for the three different PBDE debromination processes are controlled by C–Br bond dissociation energy. With the model from the present study, the major debromination products for any PBDE congener released into the environment can be predicted. Environ. Toxicol. Chem. 2010;29:770–778. © 2010 SETAC
Ecological models and pesticide risk assessment: Current modeling practice
Authors: Schmolke Amelie , Thorbek Pernille , Chapman Peter , Grimm Volker
Published: February 2010

Ecological risk assessments of pesticides usually focus on risk at the level of individuals, and are carried out by comparing exposure and toxicological endpoints. However, in most cases the protection goal is populations rather than individuals. On the population level, effects of pesticides depend not only on exposure and toxicity, but also on factors such as life history characteristics, population structure, timing of application, presence of refuges in time and space, and landscape structure. Ecological models can integrate such factors and have the potential to become important tools for the prediction of population-level effects of exposure to pesticides, thus allowing extrapolations, for example, from laboratory to field. Indeed, a broad range of ecological models have been applied to chemical risk assessment in the scientific literature, but so far such models have only rarely been used to support regulatory risk assessments of pesticides. To better understand the reasons for this situation, the current modeling practice in this field was assessed in the present study. The scientific literature was searched for relevant models and assessed according to nine characteristics: model type, model complexity, toxicity measure, exposure pattern, other factors, taxonomic group, risk assessment endpoint, parameterization, and model evaluation. The present study found that, although most models were of a high scientific standard, many of them would need modification before they are suitable for regulatory risk assessments. The main shortcomings of currently available models in the context of regulatory pesticide risk assessments were identified. When ecological models are applied to regulatory risk assessments, we recommend reviewing these models according to the nine characteristics evaluated here. Environ. Toxicol. Chem. 2010;29:1006–1012. © 2010 SETAC
UO 22+ speciation determines uranium toxicity and bioaccumulation in an environmental Pseudomonas sp. isolate
Authors: VanEngelen Michael R. , Field Erin K. , Gerlach Robin , Lee Brady D. , Apel William A. , Peyton Brent M.
Published: February 2010

In the present study, experiments were performed to investigate how representative cellulosic breakdown products, when serving as growth substrates under aerobic conditions, affect hexavalent uranyl cation (UO 22+) toxicity and bioaccumulation within a Pseudomonas sp. isolate (designated isolate A). Isolate A taken from the Cold Test Pit South (CTPS) region of the Idaho National Laboratory (INL), Idaho Falls, ID, USA. The INL houses low-level uranium-contaminated cellulosic material and understanding how this material, and specifically its breakdown products, affect U-bacterial interactions is important for understanding UO 22+ fate and mobility. Toxicity was modeled using a generalized Monod expression. Butyrate, dextrose, ethanol, and lactate served as growth substrates. The potential contribution of bicarbonate species present in high concentrations was also investigated and compared with toxicity and bioaccumulation patterns seen in low-bicarbonate conditions. Isolate A was significantly more sensitive to UO 22+ and accumulated significantly more UO 22+ in low-bicarbonate concentrations. In addition, UO 22+ growth inhibition and bioaccumulation varied depending on the growth substrate. In the presence of high bicarbonate concentrations, sensitivity to UO 22+ inhibition was greatly mitigated, and did not vary between the four substrates tested. The extent of UO 22+ accumulation was also diminished. The observed patterns were related to UO 22+ aqueous complexation, as predicted by MINTEQ (ver. 2.52) (Easton, PA, USA). In the low- bicarbonate medium, the presence of positively charged and unstable UO 22+-hydroxide complexes explained both the greater sensitivity of isolate A to UO 22+, and the ability of isolate A to accumulate significant amounts of UO 22+. The exclusive presence of negatively charged and stable UO 22+-carbonate complexes in the high bi-carbonate medium explained the diminished sensitivity of isolate A to UO 22+ toxicity, and limited ability of isolate A to accumulate UO 22+. Environ. Toxicol. Chem. 2010;29:763–769. © 2010 SETAC
Larvicidal properties of decomposed leaf litter in the subalpine mosquito breeding sites
Authors: David Jean-Philippe , Rey Delphine , Cuany Andre , Bride Jean-Marc , Meyran Jean-Claude
Published: February 2010

The larvicidal properties of the dietary leaf litter originating from the vegetation surrounding the subalpine mosquito breeding sites were investigated by using 10-month decomposed alder leaf litter against different field collections of culicine taxa of various ecological origin (Aedes cantans, Aedes caspius, Aedes cataphylla, Aedes detritus, Aedes punctor, Aedes pullatus, Aedes rusticus, Anopheles claviger, Culex hortensis, Culex pipiens, Culiseta morsitans). Larvae originating from sites with polyphenol-poor vegetation appeared more sensitive to ingested leaf litter than those originating from sites with polyphenol-rich vegetation. Within a given taxon (e.g., A. rusticus, A. cataphylla, C. hortensis), the overall levels of cytochrome P450 monooxygenase and esterase activities appeared higher in larvae able to feed on leaf litter than in pupae and adults unable to feed on leaf litter. This suggests the involvement of these enzymes in the detoxification mechanisms responsible for larval tolerance to polyphenols of the dietary leaf litter. Such a tolerance of the larval stage thus appears as fundamental in the ecotoxicological adaptation of mosquito taxa to the polyphenolic profiles of the riparian vegetation.
Relative sensitivity of bull trout (Salvelinus confluentus) and rainbow trout (Oncorhynchus mykiss) to acute exposures of cadmium and zinc
Authors: Hansen James A. , Welsh Paul G. , Lipton Josh , Cacela Dave , Dailey Anne D.
Published: February 2010

Bull trout (Salvelinus confluentus) were recently listed as threatened in the United States under the federal Endangered Species Act. Present and historical habitat of this species includes waterways that have been impacted by metals released from mining and mineral processing activities. We conducted paired bioassays with bull trout and rainbow trout (Oncorhynchus mykiss) to examine the relative sensitivity of each species to Cd and Zn independently and as a mixture. A total of 15 pairs of acute toxicity bioassays were completed to evaluate the effects of different water hardness (30 or 90 mg/L as CaCO3), pH (6.5 or 7.5), and temperature (8 or 12°C) on Cd and Zn toxicity. For both species, the acute toxicity of both Cd and Zn was greater than previously observed in laboratory studies. Bull trout were about twice as tolerant of Cd and about 50% more tolerant of Zn than were rainbow trout. Higher hardness and lower pH water produced lower toxicity and slower rates of toxicity in both species. Elevated temperature significantly increased the sensitivity of bull trout to Zn but decreased the sensitivity (not significantly) of rainbow trout to Zn. At a hardness of 30 mg/L, the toxicity values (i.e., median lethal concentration; 120-h LC50) for both species were lower than the current U.S. national water quality criteria for protection of aquatic life, indicating that current national criteria may not be protective of sensitive salmonids—including the threatened bull trout—in low calcium waters.
Aminolevulinic acid dehydratase activity in American dippers (Cinclus mexicanus) from a metal-impacted stream
Authors: Strom Sean M. , Ramsdell Howard S. , Archuleta Andrew S.
Published: February 2010

Blood samples collected from adult and nestling American dippers (Cinclus mexicanus) along the Arkansas River (CO, USA), a stream impacted by discharges from historical mining operations, and a reference stream were analyzed for lead concentration and δ-aminolevulinic acid dehydratase (ALAD) activity. Median ALAD activities of adult and nestling dippers from the Arkansas River were found to be significantly different from median ALAD activities of reference adults and nestlings (p = 0.002 and p = 0.028). Median ALAD activity for adult dippers from the Arkansas River was more than 50% lower relative to reference adults and activity approached a level close to 50% lower in nestlings from the same site. Median blood lead concentrations from adult (range 15.4–386.0 ppb) and nestling (range 12.1–323.0 ppb) dippers from the Arkansas River were found to be significantly different from median blood lead concentrations of reference adult (range 4.2–29.6 ppb) and nestling (range 4.2–8.2 ppb) dippers (p < 0.001 and p = 0.011). The median hematocrit level in adult dippers did not vary between sites (p = 0.73), whereas the median hematocrit level of nestling dippers from the reference site was significantly lower compared to Arkansas River nestlings (p = 0.042). Blood lead concentration in both adult and nestling dippers was found to be significantly correlated with invertebrate lead concentration (r = 0.81, p < 0.001 and r = 0.62, p = 0.01, respectively). Highly significant negative correlations were observed between blood lead concentration and ALAD activity in both adult and nestling dippers (r = −0.86, p < 0.001 and r = −0.84, p < 0.001, respectively). This study suggests that dippers (both adults and nestlings) from the Arkansas River have significantly lower ALAD activity and significantly higher blood lead concentrations compared to reference values. The measurement of ALAD activity may be a sensitive and accurate biomarker for environmental lead exposure in dippers.
Lethal and sublethal effects of polychlorinated biphenyls onRana sylvaticatadpoles
Authors: Savage Wesley K. , Quimby Fred W. , DeCaprio Anthony P.
Published: February 2010

In static experiments, we exposed tadpoles of the wood frog (Rana sylvatica) to sediment collected from a riverine wetland in the St. Lawrence River basin that is highly contaminated with polychlorinated biphenyls (PCBs). Significant mortality occurred early in the experiment and was not explained by a simple dose-dependent relationship. Direct sediment contact resulted in higher tadpole mortality compared with tadpoles suspended in mesh containers above the sediment. Sublethal effects of exposure were also apparent, characterized by behavioral abnormalities, including reduced activity levels and swimming speed, that differed depending on whether tadpoles were in contact with or suspended above the sediment. We demonstrate in this experiment that PCB-contaminated sediment induced significant mortality and behavioral dysfunction in early development, but the effects on natural populations existing in the contaminated region is not known.
Biochemical and behavioral effects of carbofuran in goldfish (Carassius auratus)
Authors: Bretaud Sandrine , Saglio Philippe , Saligaut Christian , Auperin Benoit
Published: February 2010

The effects of concentration (5,50, and 500 μg/L) and duration (24, 48 h) of exposure to carbofuran, a carbamate insecticide, were assessed on brain catecholamine (norepinephrine [NE] and dopamine), plasma glucose, and hepatic glycogen contents and behavioral activities of goldfish (Carassius auratus). After 24 h of exposure to 50 and 500 μg/L, the level of NE was increased in the olfactory bulbs. The same effect was observed after a 48-h exposure to 500 and 50 μg/L in the telencephalic hemispheres and in the hypothalamus, respectively. An increase in the level of dopamine was also found in hypothalamus after 48 h of exposure to 500 μg/L carbofuran. Plasma glucose increased in concentration after both periods of exposure to carbofuran at 50 and 500 μg/L. Hepatic glycogen concentration decreased after a 48-h exposure to the highest concentration. Behavioral endpoints related to swimming pattern and social interactions were affected after a 24-h exposure to the lowest concentration tested (5 μg/L). The relative sensitivities of these different types of responses to exposure to carbofuran are discussed in light of data on the neurotoxic effects of carbamate and organophosphate insecticides in fish.
Chemical toxicity indicators for human health: Case study for classification of chronic noncancer chemical hazards in life-cycle assessment
Authors: Owens J. William
Published: February 2010

The classification scheme for human health indicators in life-cycle assessment (LCA) and other toxicity scores is proposed based on identifiable target organ or system toxicity. This scheme represents a compromise between a subjective single overall score and highly detailed toxic mechanisms of action. A case study was used to evaluate the proposed classification scheme. The data on 117 high production volume organic chemicals were extracted from the U.S. Environmental Protection Agency (U.S. EPA) integrated risk information system (IRIS) database. Based on the critical effect listed in the database, almost all chemicals were easily and clearly classified into the proposed categories. However, there were significant variations in test species, protocol, duration, toxicological parameter measured, etc., among different toxicity studies. Importantly, the toxicological critical effects observed, even for the same target organ or system, differed from chemical to chemical and were not equivalent. Using hepatotoxicity as an example, critical effects included changes in organ weight, a variety of different histopathological changes, and changes in circulating hepatic enzyme levels. Therefore, no universal, common basis was identified for biological equivalency in order to compare or to aggregate chemicals into an overall toxicity score. A recent proposal to develop a characterization system based on disability-adjusted life years (DALYs) was also evaluated. No means were found to extrapolate animal critical effects data to predict any diminution in human lifetimes or the appearance and intensity of human disability. Still, LCA presents an ideal starting point for toxicological analysis by conducting a system-wide analysis that inventories and maps the sources of potentially important human pollutants. The LCA results could then facilitate initial toxicological and risk evaluations for those sources and chemicals and set the stage for a more detailed and informed analysis by professional toxicologists.
Isotopic and geochemical tracers reveal similarities in transit times in contrasting mesoscale catchments
Authors: Speed M. , Tetzlaff D. , Soulsby C. , Hrachowitz M. , Waldron S.
Published: February 2010

There is a need for more isotopic tracer studies at the mesoscale to extend our understanding of catchment transit times and their associated controls beyond smaller experimental sites (typically < 10 km2). This paper, therefore, examines the isotope hydrology of six mesoscale (101–102km2) sub‐catchments of the 2000 km2basin of the River Dee in northern Scotland. All the catchments were upland in character (mean altitude > 400 m) with similar suites of soil coverage (predominantly regosols, gleys, peats and podzols), although the relative distribution varied, as did the presence of other landscape features such as aquifers in Quaternary drifts and lakes. Input–output relationships of δ18O in precipitation and runoff revealed contrasting responses and differential damping which were broadly consistent with catchment characteristics. The mean transit times (MTTs) were estimated using a convolution integral with a Gamma distribution as the transfer function. These varied from 528 days in the most responsive catchments to > 800 days in catchments where the tracer signature was most damped. Shorter MTTs were found in sub‐catchments with a higher percentage cover of responsive soils (i.e. regosols, gleys and peats), whilst sub‐catchments with longest MTTs had a higher coverage of free‐draining podzolic and alluvial soils, as well as significant amount of stored water either in fluvio‐glacial aquifers or large lakes. The MTT of all six catchments had the same order of magnitude; this contrasts with studies in the Scottish Highlands with smaller (<10 km2) catchments where MTT has been shown to vary between 60 and 1200 days. Copyright © 2010 John Wiley & Sons, Ltd.
Estimating the impact of rural land management changes on catchment runoff generation in England and Wales
Authors: Hess T. M. , Holman I. P. , Rose S. C. , Rosolova Z. , Parrott A.
Published: February 2010

Although reviews of the scientific literature have failed to demonstrate conclusive evidence for the impact of rural land management on peak runoff rates, increasing emphasis is being placed by policy makers on its role in catchment‐scale flood risk management. Poor soil and field conditions can lead to higher rates of runoff from extreme rainfall events; however, the improvement of land condition will lead to differing runoff responses depending on land use, soil type and climatic regime. This study has evaluated the relative impact of improvement of field and soil conditions on peak daily runoff rates for a range of soils and vegetation cover types across England and Wales. It has shown that rural land management changes could be expected to make a positive contribution to sustainable flood risk management, especially for more frequent events. The greatest relative reduction in runoff can be achieved through the improvement of degraded permeable soils under managed grassland in drier regions. Taking a plausible scenario of land management improvement in arable and grassland systems, the relative reduction in peak runoff was estimated for 518 policy units as defined in the Environment Agency's Catchment Flood Management Plans. For the 1 in 100 year event, there were only a few policy units where the expected reduction in runoff exceeded 5%. Rural land management practices which are likely to be beneficial to flood risk management may afford some protection to areas where structural measures may not be implemented for cost–benefit reasons, and may help to offset some of the anticipated increases in flood risk associated with climate change. Copyright © 2010 John Wiley & Sons, Ltd.