bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk assessment methodologies for exposure of great horned owls (Bubo virginianus) to PCBs on the Kalamazoo river, Michigan
Authors: Strause Karl D , Zwiernik Matthew J , Newsted John L , Neigh Arianne M , Millsap Stephanie D , Park Cyrus S , Moseley Pamela P , Kay Denise P , Bradley Patrick W , Jones Paul D , Blankenship Alan L , Sikarskie James G , Giesy John P 
Published: January 2008

Abstract
Dietary exposures of great horned owls (GHO; Bubo virginianus) to polychlorinated biphenyls (PCBs) in the terrestrial food web at the Kalamazoo River, Michigan, USA, were examined. Average potential daily doses (APDD) in GHO diets were 7- to 10-fold and 3-fold greater at the more contaminated location versus a reference location for site-specific exposures quantified as total PCBs and 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQWHO-Avian), respectively. Wetland/aquatic prey contributed significantly to PCB exposure and APDD. Estimates of risk based on comparison of modeled dietary intake (e.g., APDD) to toxicity reference values (TRVs), using a hazard quotient (HQ) methodology, varied between diet composition methods (mass basis vs numeric basis). Mass-basis compositions yielded greater HQs at all sites. Potential risks associated with dietary exposures (”bottom-up” risk assessment methodology) were less than (HQ &lt; 1) benchmarks for effects,. This result is consistent with risk estimates based on concentrations in tissues (”top-down” risk assessment methodology), and indicated PCBs posed no significant risk to terrestrial raptor species. Colocated and concurrent studies that evaluated GHO reproductive performance (nestling productivity) and relative abundance were consistent with results of the risk assessment. Measures of risk based on HQs were consistent with direct measures of ecologically relevant endpoints (reproductive fitness). Uncertainty in risk estimates is contributed during the selection of TRVs for effects in GHO based on TEQWHO-Avian because of the absence of species-specific, dose-response thresholds. This evaluation indicated that a multiple-lines-of-evidence approach provided the best estimate of risk.
Methods to develop consumption advice for methylmercury-contaminated walleye harvested by Ojibwe Tribes in the 1837 and 1842 ceded territories of Michigan, Minnesota, and Wisconsin, USA
Authors: Madsen Eric R , DeWeese Adam D , Kmiecik Neil E , Foran Jeffery A , Chiriboga Esteban D 
Published: January 2008

Abstract
The Great Lakes Indian Fish and Wildlife Commission produces consumption advisories for methylmercury in walleye (Sander vitreus) harvested by its member tribes in the 1837 and 1842 ceded territories of Michigan, Minnesota, and Wisconsin, USA. Lake-specific advice is based primarily on regressions of methylmercury concentrations on walleye length and incorporates standard reference doses to generate recommended meal frequencies. The effects of variability and uncertainty are directly incorporated into the consumption advice through confidence bounds for the general population and prediction bounds for the sensitive population. Advice is tailored to the needs of the tribes because harvest and consumption of fish are culturally important. Data were sufficient to provide consumption advice for 293 of the 449 lakes assessed. Most of these carried a recommendation of no more than 4 meals per month for the general population and no more than 1 meal per month for the sensitive population.
Societal cost-benefit analysis for soil remediation in the Netherlands
Authors: van Wezel Annemarie P , Franken Ron OG , Drissen Eric , Versluijs Kees CW , van den Berg Reinier 
Published: January 2008

Abstract
There is a political demand on the efficiency of environmental policy. Cost-benefit analyses (CBAs) can play a role in answering that demand. This societal CBA for nationwide soil remediation operations in The Netherlands distinguishes 4 alternatives for future investments. In the zero alternative government funding will be terminated. Besides this, 3 policy alternatives are distinguished that are government financed. Soil remediation benefits human health, the drinking water supply, housing, perceptions, and the ecosystem. Soil remediation also answers the concerns of the Dutch population. The benefits to health (exposure to cadmium, lead, and carcinogens), drinking water supply, and housing are expressed in monetary terms. The extent that benefits equal the money spent depends partly on the value-loaded choice for the discount rate. Use of the current discount rate of 4% will mean a slightly negative balance whichever policy alternative is chosen. Focusing on nonmoneterized benefits, such as ecology, can cause the scales to tip in another direction. Using a lower discount rate will make future benefits, such as health and drinking water supply, more important. If the discount rate drops to 2% or less, all policy alternatives lead to a positive balance. Predominantly, the health benefits that are veiled in uncertainty can become a reason for applying a surcharge and, in turn, a higher discount rate. In that case, each of the alternatives will result in a net negative balance.
Selecting and evaluating native plants for region-specific phytotoxicity testing
Authors: Olszyke David , Pfleeger Thomas , Lee E Henry , Burdick Connie , King George , Plocher Milton , Kern Jeffrey 
Published: January 2008

Abstract
In this study, we evaluated methodology to determine risks to terrestrial native plant species from potential herbicide drift, focusing on 1) selection of native species for testing, 2) growth of these species, and 3) variability in herbicide response among native species and compared with crop plants. Native plant species were selected for initial testing on the basis of spatial analysis, which indicated that species from Illinois, USA, were at potential risk for off-target effects of herbicide drift. On the basis of preliminary seed germination tests, 5 native plant species (Andropogon gerardi, Polygonum lapathifolium, Solidago canadensis, Symphyotrichum lateriflorum, and Tridens flavus) were selected for comparison with crops grown in Illinois, normally used in the US Environmental Protection Agency's (USEPA's) Vegetative Vigor Test (Avena sativa, Daucus carota, Glycine max, Solanum lycopersicon, and Zea mays), or both. When treated with low concentrations of a test herbicide, sulfometuron methyl, 2 native species, P. lapathifolium and S. canadensis, were as sensitive as the 5 crop species. The effective herbicide concentrations producing a 25% reduction in shoot dry weight (EC25) for these species, ranged from 0.00015 to 0.0014 times a field application concentration of 52 g/ha active ingredient of sulfometuron methyl. S. lateriflorum and T. flavus were less sensitive than the other native species, whereas A. gerardi was tolerant to sulfometuron methyl with no growth reduction at any herbicide concentration tested. This study indicated that native species can be successfully selected and grown, used in the suite of species used in the USEPA's phytotoxicity test to assess risks of chemical herbicides to nontarget plants. It also showed (with a limited number of species) that native species varied more in sensitivity to simulated herbicide drift than crop species often used in phytotoxicity testing and that a Weibull function was useful to calculate EC25 values when low concentrations of herbicides was used.
A study on the fundamental factors determining the efficacy of siRNAs with high C/G contents
Authors: Liao Jie-Ying , Yin James , Chen Fang , Liu Tie-Gang , Yue Jia-Chang 
Published: January 2008

AbstractAlthough there are many reports about the efficacy of siRNAs, it is not clear whether those siRNAs with high C/G contents can be used to silence their target mRNAs efficiently. In this study, we investigated the structure and function of a group of siRNAs with high C/G contents. The results showed that single siRNAs against the Calpain, Otoferlin and Her2 mRNAs could induce different silencing effects on their targets, suggesting that the accessibility to target sequences influences the efficacy of siRNA. Unexpectedly, a single siRNA could target its cognate sequence in the 3’UTR of EEF1D or the 5’UTR of hTRF2 or CDC6. Their interaction induced different modes of gene silencing. Furthermore, the introduction of mutations into the 3’ end of the passenger strand showed that the position and number of mutated nucleotides could exert some influence on the efficacy of siRNA. However, these mutations did not completely block the passenger strand from exerting its RNAi effect. Interestingly, our findings also indicated that the target mRNA might play essential roles in maintaining or discarding the guide strand in RISCs. Thus, the conclusion could be drawn that favorable siRNA sequences, accessible target structures and the fast cleavage mode are necessary and sufficient prerequisites for efficient RNAi.
Detection of metastases in breast cancer patients
Authors: Mahner S. , Schirrmacher S. , Jenicke L. , Müller V. , Habermann C. R. , Brenner W. , Dose-Schwarz J. 
Published: January 2008

SummaryDistant metastases at primary diagnosis are a prognostic key factor in breast cancer patients and play a central role in therapeutic decisions. To detect them, chest X-ray, abdominal ultrasound, and bone scintigraphy are performed as standard of care in Germany and many centers worldwide. Although FDG PET detects metastatic disease with high accuracy, its diagnostic value in breast cancer still needs to be defined. The aim of this study was to compare the diagnostic performance of FDG PET with conventional imaging. Patients, methods: A retrospective analysis of 119 breast cancer patients who presented for staging was performed. Whole-body FDG-PET (n=119) was compared with chest X-ray (n=106) and bone scintigraphy (n=95). Each imaging modality was independently assessed and classified for metastasis (negative, equivocal and positive. The results of abdominal ultrasound (n=100) were classified as negative and positive according to written reports. Imaging results were compared with clinical follow-up including follow-up imaging procedures and histopathology. Results: FDG-PET detected distant metastases with a sensitivity of 87.3% and a specificity of 83.3%. In contrast, the sensitivity and specificity of combined conventional imaging procedures was 43.1% and 98.5%, respectively. Regarding so-called equivocal and positive results as positive, the sensitivity and specificity of FDG-PET was 93.1% and 76.6%, respectively, compared to 61.2% and 86.6% for conventional imaging. Regarding different locations of metastases the sensitivity of FDG PET was superior in the detection of pulmonary metastases and lymph node metastases of the mediastinum in comparison to chest x-ray, whereas the sensitivity of FDG PET in the detection of bone and liver metastases was comparable with bone scintigraphy and ultrasound of the abdomen. Conclusions: FDG-PET is more sensitive than conventional imaging procedures for detection of distant breast cancer metastases and should be considered for additional staging especially in patients with high risk primary breast cancer.
Geometric models in dosimetry of thyroid remnant mass
Authors: Lončarić S. , Huić D. , Dodig D. , Grošev D. 
Published: January 2008

SummaryAim: Absorbed dose to thyroid remnant tissue after 131I ablation becomes mass/size-dependent. This is a direct consequence of the small remnant size and radiation escape starts to be relevant. The self-absorbed fraction becomes mass/size-dependent. We have used Monte Carlo simulations to investigate the influence of the thyroid remnant shape upon the absorbed fraction calculation. Methods: Thyroid residue was modeled using spherical, cylindrical and elliptical shapes. Uniform beta activity distribution and unit density medium (water) within a remnant was assumed. For each of the geometrical models beta self-absorbed fraction (ϕγ) was calculated using Monte Carlo codes, while the mean absorbed dose per unit cumulated activity (Sγ) was calculated using MIRD formalism. Results: For spherical objects Ömono for mean beta energy (E = 0.182 MeV) of 131I is always greater than ϕγ calculated for the complete beta spectrum. For spheres having diameters 2–6 mm and assumption ϕγ=1, Sγ is overestimated by 11–37%. For cylinder and prolate spheroid of the same length and thickness, Sγ for cylinder is 30% smaller because of the greater mass. Similarly, elliptical cylinder and general ellipsoid of the same length and the same perpendicular dimensions (width and breadth), have similar ϕγ, while Sγ for elliptical cylinder is correspondingly smaller. Conclusion: For accurate dosimetry of thyroid remnants having masses <1 g and chordal lengths <1 cm it is necessary to calculate ϕγ for the full beta spectrum, or Sγ will be overestimated. The shape of the remnant may also be important since elongated non-spherical objects may also have ϕγ < 1.
A genetic‐based neuro‐fuzzy controller for blind equalization of time‐varying channels
Authors: Panigrahi Siba Prasada , Nayak Santanu Kumar , Padhy Sasmita Kumari 
Published: January 2008

AbstractThis paper presents a neuro‐fuzzy network (NFN) where all its parameters can be tuned simultaneously using genetic algorithms (GAs). The approach combines the merits of fuzzy logic theory, neural networks and GAs. The proposed NFN does not requirea prioriknowledge about the system and eliminates the need for complicated design steps such as manual tuning of input–output membership functions, and selection of fuzzy rule base. Although, only conventional GAs have been used, convergence results are very encouraging. A well‐known numerical example derived from literature is used to evaluate and compare the performance of the network with other equalizing approaches. Simulation results show that the proposed neuro‐fuzzy controller, all parameters of which have been tuned simultaneously using GAs, offers advantages over existing equalizers and has improved performance.From the perspective of application and implementation, this paper is very interesting as it provides a new method for performing blind equalization. The main contribution of this paper is the use of learning algorithms to train a feed‐forward neural network for M‐ary QAM and PSK signals. This paper also provides a platform for researchers of the area for further development. Copyright © 2008 John Wiley & Sons, Ltd.
Geographic variation in Thomas langur (Presbytis thomasi) loud calls
Authors: Wich Serge A , Schel Anne Marijke , de Vries Han 
Published: January 2008

AbstractGeographic variation in primate vocalizations has been described at two levels. First, at the level of acoustic variation within the same call type between populations and, second, at the level of presence or absence of certain call types in different populations. Acoustic variation is of interest because there are several factors that can explain this variation, such as gene flow, ecological factors and population density. Here we focus on the first level in a Southeast Asian primate, the Thomas langur. We recorded male loud calls in four populations that differed in their geographic distances from each other and had varying geographic barriers in between them, such as rivers and mountain ranges. The presence of these barriers leads to expectations of loud call variation under the gene flow model, which are examined here. We conducted a principal components analysis to condense the number of acoustic variables. With a subsequent discriminant function analysis on the six principal component scores, we found that the percentage of loud calls that were correctly assigned to a population was relatively high (50.0–76.2%) when three randomly selected loud calls from each male were used. Using the discriminant functions from this analysis to predict population membership of the remainder of the loud calls yielded lower, but still relatively high correct assignment percentages (26.2–66.7%). Analyses to examine the influence of barriers on similarities between populations confirm our expectations. We discuss that differences in loud calls are probably most parsimoniously explained by gene flow (or the lack thereof) between the populations and that future studies of genetic differences are crucial to test this hypothesis. Am. J. Primatol. 70:566–574, 2008. © 2008 Wiley‐Liss, Inc.
New anti‐bacterial polychelates: synthesis, characterization, and anti‐bacterial activities of thiosemicarbazide–formaldehyde resin and its polymer–metal complexes
Authors: Parveen Shadma , Ahamad Tansir , Nishat Nahid 
Published: January 2008

AbstractNew polymeric ligand (resin) was prepared by the condensation of thiosemicarbazides with formaldehyde in the presence of acidic medium. Thisemicarbazide–formaldehyde polymer–metal complexes were prepared with Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) in 1:2 metal:ligand molar ratio. The polymeric ligand and its polymer–metal complexes were characterized by elemental analysis, thermogravimetric analysis (TGA), FTIR, 13C NMR and 1H NMR. The geometry of central metal ions was conformed by electronic (UV–vis) and EPR spectra. The antibacterial activities of all the synthesized polymers were investigated against Bacillus subtilis and Staphylococcus aureus (Gram‐positive) and Escherichia coli and Salmonella typhi (Gram‐negative). These compounds showed excellent activities against these bacteria using the shaking flask method. Copyright © 2008 John Wiley & Sons, Ltd.
Statistical algorithms for identification of astronomical X‐ray sources
Authors: Ziaeepour H. , Rosen S. 
Published: January 2008

AbstractObservations of present and future X‐ray telescopes include a large number of ipitous sources of unknown types. They are a rich source of knowledge about X‐ray dominated astronomical objects, their distribution, and their evolution. The large number of these sources does not permit their individual spectroscopical follow‐up and classification. Here we use Chandra Multi‐Wavelength public data to investigate a number of statistical algorithms for classification of X‐ray sources with optical imaging follow‐up. We show that up to statistical uncertainties, each class of X‐ray sources has specific photometric characteristics that can be used for its classification. We assess the relative and absolute performance of classification methods and measured features by comparing the behaviour of physical quantities for statistically classified objects with what is obtained from spectroscopy. We find that among methods we have studied, multi‐dimensional probability distribution is the best for both classifying source type and redshift, but it needs a sufficiently large input (learning) data set. In absence of such data, a mixture of various methods can give a better final result.We discuss some of potential applications of the statistical classification and the enhancement of information obtained in this way. We also assess the effect of classification methods and input data set on the astronomical conclusions such as distribution and properties of X‐ray selected sources. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
EM Cygni: A study of its eclipse timings
Authors: Csizmadia Sz. , Nagy Zs. , Borkovits T. , Hegedüs T. , Bíró I.B. , Kiss Z.T. 
Published: January 2008

AbstractEM Cygni is a Z Cam‐subtype eclipsing dwarf nova. Its orbital period variations were reported in the past but the results were in conflict to each other while other studies allowed the possibility of no period variation. In this study we report accurate new times of minima of this eclipsing binary and update itsO –C diagram.We also estimate the mass transfer rate in EM Cygni system and conclude that the mass transfer is far from the critical value. The mass transfer rate determined from the eclipse timings is in agreement with the spectroscopically determined value. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photometric monitoring of the blazar 3C 345 for the period 1996–2006
Authors: Mihov B. , Bachev R. , Slavcheva‐Mihova L. , Strigachev A. , Semkov E. , Petrov G. 
Published: January 2008

AbstractWe present the results of the blazar 3C 345 monitoring in Johnson‐Cousins BVRI bands for the period 1996–2006. We have collected 29 V and 43 R data points for this period; the BI light curves contain a few measurements only. The accuracy of our photometry is not better than 0.03 mag in the VR bands. The total amplitude of the variability obtained from our data is 2.06 mag in the V and 2.25 mag in the R band. 3C 345 showed periods of flaring activity during 1998/99 and 2001: a maximum of the blazar brightness was detected in 2001 February – 15.345 mag in the V and 14.944 mag in the R band. We confirm that during brighter stages 3C 345 becomes redder; for higher fluxes the colour index seems to be less dependent on the magnitude. The intra‐night monitoring of 3C 345 in three consecutive nights in 2001 August revealed no significant intra‐night variability; 3C 345 did not show evident flux changes over timescales of weeks around the period of the intra‐night monitoring. This result supports the existing facts that intra‐night variability is correlated with rapid flux changes rather than with specific flux levels. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Soft gamma repeaters activity in time
Authors: Popov S.B. 
Published: January 2008

AbstractIn this short note I discuss the hypothesis that bursting activity of magnetars evolves in time analogously to the glitching activity of normal radio pulsars (i.e. sources are more active at smaller ages), and that the increase of the burst rate follows one of the laws established for glitching radio pulsars. If the activity of soft gamma repeaters decreases in time in the way similar to the evolution of core‐quake glitches (∝t5/2), then it is more probable to find the youngest soft gamma repeaters, but the energy of giant flares from these sources should be smaller than observed 1044–1046 erg as the total energy stored in a magnetar's magnetic field is not enough to support thousands of bursts similar to the prototype 1979 March 5 flare. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Imaging of deep vein thrombosis
Authors: Orbell J H , Smith A , Burnand K G , Waltham M 
Published: January 2008

Abstract

Background
Deep vein thrombosis of the leg affects 1–2 per cent of the population with an annual incidence of 0·5–1 per 1000. It presents with non-specific symptoms and signs making clinical diagnosis difficult. Techniques to image and diagnose this condition are advancing rapidly.

Methods and results
A literature review from 1980 to 2007 was undertaken using PubMed, The Cochrane Library, Medline and Embase. The most frequently used diagnostic test is duplex ultrasonography which is accurate above the knee and has a low cost, but is limited by inaccuracy when assessing the pelvic and distal veins and in diagnosing a new thrombosis in the post-thrombotic limb. Magnetic resonance imaging (MRI) and sonographic elasticity imaging are more recent techniques that have shown promise in overcoming these limitations. However, their availability is currently restricted because they are expensive. Computed tomography (CT) is sensitive, specific and provides good imaging of the pelvis. It has the advantage that it can be performed at the same time as CT pulmonary angiography.

Conclusion
MRI has some specific advantages over duplex ultrasonography, but requires refinement before it can be used clinically. Venography or CT venography should be considered when duplex scanning is inadequate.