bluuebunny/crossref_metadata_2025 huggingface dataset:
Composing Across Multiple Media
Authors: Ranker Jason
Published: March 2008

This is a qualitative case study of two students' composing processes as they developed a documentary video about the Dominican Republic in an urban, public middle school classroom. While using a digital video editing program, the students moved across multiple media (the Web, digital video, books, and writing), drawing semiotic resources from each as they did so. Using sociosemiotic and dialogic-intertextual theoretical frameworks, the author examines how the interface of the video editing program influenced the students' composing by making new types of semiotic resources available and new means of combining these resources. As they moved across these media in a nonlinear fashion, the students created an interactive context for composing that transcended the individual possibilities of each respective medium. This suggests that multimedial composing environments offer a rich intertextual landscape and unique ways of making meanings.
Herb and Supplement Use Among the Retail Population of an Independent, Urban Herb Store
Authors: Archer Erin L. , Boyle Diane K.
Published: March 2008

The prevalence of herbal medicine use among American adults is well documented. Because of the possible herb–drug interactions, health care providers need to be aware of herb and supplement use by their patients. This descriptive pilot study ( N = 35) was designed to explore the demographics, beliefs, concurrent pharmaceutical use with herbs and supplements and their primary sources of information, and reporting of use to health care providers by customers at a retail specialty “herb” store. Results revealed that 62.5% of study participants who used herbs regularly also used pharmaceuticals. Among those who used herbs and supplements with pharmaceuticals, only 33% reported that they “always” tell their care provider about them. Forty-one percent reported that they receive most of their information about herbs and supplements from retail staff, but only 3% of participants reported that their primary source of information was a doctor, nurse, or pharmacist. Findings provide direction for future study.
Distinguishing Nursing Art: Patient, Researcher, and Student Views: Nursing Is an Art
Authors: Batti Lara
Published: March 2008

In this response to research, the author likens the art of nursing to a work of art: abstract with blurred lines but lots of opportunity for interpretation. Frances, a patient interviewed by Dr. Kathryn Gramling as part of her research into patients' perception of nursing care, along with her family, felt comforted by her nurse, who devoted some of his own time to ensuring that Frances understood the procedure she needed and spent time meeting her need for human contact. The author experienced something similar during a hospital stay: She too had a nurse who spent time and gave comfort. The result is that the author understands the art of nursing as it relates to an extra effort to be human and demonstrate empathy. The poem written by Dr. Gramling in response to Frances confirms the patient's view of the art of nursing.
Distinguishing Nursing Art: Patient, Researcher, and Student Views: The Art of Nursing
Authors: Eydenberg Kaitlyn
Published: March 2008

The author of this article explores her definition of the art of nursing through a response to an interview by Dr. Kathryn Gramling with a patient named Frank. She determines that nursing, although it also requires technical skill and a strong knowledge base, becomes art when the practitioner adopts the caring skills of compassion, touching, and empathy. The poem Dr. Gramling wrote in response to her contact with Frank reinforces the definition created by the author. When some patients enter a hospital, they experience certain feelings, such as fear, uncertainty, and helplessness. They are placed in a strange setting and are not in the best of health, but each patient deals with sickness differently. Some may act frightened, while others may act impatient and uncooperative. Often, it is a nurse's duty to help ease a patient through this difficult transition. The way a nurse does this makes all the difference to a patient's stay at the hospital. A nurse's impact on the patient can affect the patient either positively or negatively. A nurse must go above and beyond the technical part of nursing in order to make nursing an art.
Going Outdoors Daily Predicts Long-Term Functional and Health Benefits Among Ambulatory Older People
Authors: Jacobs Jeremy M. , Cohen Aaron , Hammerman-Rozenberg Robert , Azoulay Daniel , Maaravi Yoram , Stessman Jochanan
Published: March 2008

Objective: This article examines the association between frequency of going out of the house and health and functional status among older people. Method: A randomly chosen cohort of ambulatory participants born in 1920 or 1921 from the Jerusalem Longitudinal Study underwent assessments for health, functional, and psychosocial variables at ages 70 and 77. Twelve-year mortality data were collected. Results: Women went out daily less than did men. Participants going out daily at age 70 reported significantly fewer new complaints at age 77 of musculoskeletal pain, sleep problems, urinary incontinence, and decline in activities of daily living (ADLs). Logistic regression analysis indicated that not going out daily at age 70 was predictive of subsequent dependence in ADL, poor self-rated health, and urinary incontinence at age 77. Discussion: Going out daily is beneficial among independent older people, correlating with reduced functional decline and improved health measures.
Inventing the “All-American Boy”
Authors: Weaver-Hightower Marcus B.
Published: March 2008

In the United States and internationally in recent years, a great deal of attention, particularly within popular publications, has been paid to boys, their rearing, and their education. While much of this concern has clearly had conservative aims or at least conservative overtones, even the more progressive elements of the concern over boys have been “pulled into” the conservative camp. Indeed, the entire advocacy position for boys has often been (discursively, at least) relegated to conservatism. This article examines why this happens and, more important, shows how this occurs on a small scale. The author focuses here on how conservatives “pull in” rather than how the Left “pushes out.” Using frameworks laid out by Apple, Bernstein, Bourdieu, and others, the author shows how an unlikely artifact—a toy catalog—might serve as a case study for the methods conservative groups use to pull the debate, as well as those teachers and parents who are intimately affected by its outcomes, under the “umbrella” of conservative modernization. These techniques include mobilizing general similarities to the boys debate, appealing to the tastes of particular class fractions, using recontextualizing processes, appealing through visual forms, accounting for dissonances, creating the constitutive outside, and perhaps most important, providing a possible solution to the “problem” of boys. I discuss implications of these techniques and advocate a reclaiming of the debates by progressive forces.
Health beliefs and the politics of Cree well-being
Authors: Adelson Naomi
Published: March 2008

Concepts of health are powerful statements of cultural ideals, interpreted within and shaped by circumstance and history. For the Whapmagoostui Cree of northern Quebec, ideals of health are found within the narratives of past hunting livelihoods, thus integrating diverse symbols of Cree subsistence and social practices. By addressing the conditions through which this concept of health is constituted, I illustrate how narratives of ?health? are synonymous with Cree social and political well-being. For the Cree, health is not simply physical well-being, but one form of articulating Cree national identity in response to a continued challenge to that identity and is thus located within a text of historical accountings, land, and the production and interpretation of traditional activities.
Birth in the South and chronic disease mortality rates in the late twentiethcentury United States
Authors: Greenberg Michael R. , Schneider Dona F.
Published: March 2008

Southern-born black and white Americans suffered severe economic deprivations during the first half of the twentieth century. We hypothesized that these conditions increased their risks of dying from cancer, diabetes, heart and cerebrovascular diseases. Mortality files for the years 1979 to 1991 for the United States and a specially constructed US Census population file were used to calculate age-specific and age-adjusted death rates for black and white males and females by region of birth and region of residence at time of death. Death rates of Southern-born populations were compared to the death rates of populations born in the Northeast, Midwest and West. The Southern-born effect was manifested in higher death rates from cancer, diabetes, heart and cerebrovascular diseases for both black and white populations. The Southern-born effect is larger than black/white differences for cancer and of similar magnitude for heart and cerebrovascular diseases. Follow-up investigations are needed to isolate key elements of the Southernborn effect that can be addressed through interventions.
The Correlation Between PMV and Dissatisfaction on the Basis of the ASHRAE and the McIntyre Scale — Towards an Improved Concept of Dissatisfaction
Authors: von Grabe Jörn , Winter Stefan
Published: March 2008

This paper proposes a concept of dissatisfaction that is based on the correlation between the McIntyre and the ASHRAE votes of the ASHRAE RP-884 Adaptive Model Project — Data. The correlation shows that people who are voting with ASHRAE ·2 or beyond are not necessarily dissatisfied (which is the basic assumption of the classical PPD concept) and vice versa, that people who are voting between -1 and 1 are not necessarily satisfied with their thermal environment. The data set was divided into several factors (age, gender, building type, indoor conditions, outdoor temperatures) to analyze any dependencies of the preference on these factors. Processing the data finally lead to a predictive system that is — applied to the source data — a better predictor for preference than the PPD. This improvement needs affirmation by the application of the predictive system to an independent data set.
Landfilling with Mixed Wastes: Environmental Effects of Wastes and their Management in the Eastern Black Sea Region of Turkey
Authors: Beyazli Dilek , Aydemir Şinasi
Published: March 2008

Adding mixed waste to coastal landfill areas is common in the Eastern Black Sea Region of Turkey. The area studied in this paper covers the coastal cities of Ordu, Giresun, Trabzon, and Rize. All these cities have gained extensive landfill areas from the shores just in front of them. Residential waste and rubble has been infilled along the shores of the cities for a distance of ~30—50 m from the sea side since the 1970s. This now supports a double lane road construction that follows the shore line. Both actions have caused damage to sea shore ecology.

The consequences of using mixed waste in landfill is discussed under the following headings: health impacts of wastes (scavenging sea gulls may carry infectious diseases); composition and chemical properties of wastes; visual and environmental impact; lack of integration with development plans for the re-use of filled lands; dumping techniques. This paper was prepared by analysis of maps, visual and photographic analysis, site investigations and evaluation of municipal records from the region.
Assessment of Radionuclide Concentrations in Water Supply from Bore-holes in Ogbomosoland, Western Nigeria
Authors: Awodugba A.O. , Tchokossa P.
Published: March 2008

The level of radionuclide concentration in water from bore-holes in selected areas of Ogbomosoland, a region consisting of five local governments, was determined. Concentration of 238U, 232Th, and 40K was determined for the water samples from eight bore-holes around Ogbomosoland by γ-ray spectrometry with a high-purity germanium (HPGe) detector connected to a multichannel analyzer. All the water samples from these bore-holes were found to contain acceptable levels of radionuclides with mean activity values of 3.98 ±0.26, 11.00 ±2.58, and 17.73 ± 5.04 Bql -1 for 40K, 232Th, and 238U, respectively showing that the mean activity of 238U for all the samples is the highest when compared with those of 40K and 232Th. Water samples from Ikoyi had the highest radionuclide content although 40K concentration was below detectable level. Water samples from Gambari were next to Ikoyi in radionuclide content, followed by Saja, Ajinopai, Kajola, Isale-Ora, Iresa-Apa, and Owode in that order. The mean absorbed dose rate for all the area is 0.123 mSvyr-1 which is very low when compared to the recommended limit of 1mSvyr-1 for bore-hole water. Overall, the radionuclide concentration of the bore-hole water supply in Ogbomosoland is, negligible and poses no radiological hazards to the public.
Unprecedented diversity of genotypic revertants in lymphocytes of a patient with Wiskott-Aldrich syndrome
Authors: Davis Brian R. , DiCola Michael J. , Prokopishyn Nicole L. , Rosenberg Jonathan B. , Moratto Daniele , Muul Linda M. , Candotti Fabio , Michael Blaese R.
Published: March 2008

Spontaneous somatic reversions of inherited mutations are poorly understood phenomena that are thought to occur uncommonly in a variety of genetic disorders. When molecularly characterized, revertant cells have rarely exhibited more than one revertant genotype per patient. We analyzed individual allospecific T-cell clones derived from a Wiskott-Aldrich syndrome (WAS) patient identified by flow cytometry to have 10% to 15% revertant, WAS protein–expressing lymphocytes in his blood. Genotypic analysis of the clones revealed a remarkable diversity of deletions and base substitutions resulting in at least 34 different revertant genotypes that restored expression of WASp. A large fraction of these revertant genotypes were also identified in primary T cells purified from peripheral blood. These data suggest that the use of sensitive methods may reveal the presence of wide arrays of individual genotypic revertants in WAS patients and offer opportunities for further understanding of their occurrence.
Involved-Field Radiotherapy Before High-Dose Therapy and Autologous Stem-Cell Rescue in Diffuse Large-Cell Lymphoma: Long-Term Disease Control and Toxicity
Authors: Hoppe Bradford S. , Moskowitz Craig H. , Filippa Daniel A. , Moskowitz Chaya S. , Kewalramani Tarun , Zelenetz Andrew D. , Yahalom Joachim
Published: March 2008

Purpose

To analyze outcome, prognostic factors, and toxicities in patients with diffuse large-cell lymphoma (DLCL) who received involved-field radiotherapy (IFRT) before high-dose chemotherapy with autologous stem-cell rescue (ASCR).

Patients and Methods

Between January 1990 and August 2006, 164 patients with relapsed or refractory DLCL received IFRT at Memorial Sloan-Kettering Cancer Center (New York, NY) before high-dose chemotherapy and ASCR. IFRT was delivered to involved sites measuring more than 5 cm or to sites with residual disease more than 2 cm. Radiotherapy was administered in 1.5-Gy fractions twice daily to a total dose of 30 Gy. Progression-free survival and overall survival were calculated, and short- and long-term toxicity was assessed according to National Cancer Institute Common Toxicity Criteria (version 2.0). Median follow-up was 60 months (range, 2 to 187 months).

Results

Two- and 5-year progression-free survival was 62% and 53%; 2- and 5-year overall survival was 67% and 58%, respectively. Sixty-seven patients relapsed; only 10 patients relapsed completely within the radiotherapy field. There were seven early treatment-related mortalities and 11 secondary cancers (including four myelodysplastic syndromes), one of which occurred within the IFRT site and five after total-body irradiation.

Conclusion

Minimal treatment-related mortality and morbidity resulted from short, intensive, involved-field radiotherapy before high-dose chemotherapy and ASCR, which was incorporated into a salvage regimen for patients with relapsed/refractory DLCL. This chemoradiotherapy salvage regimen resulted in a low local relapse rate that could potentially translate into an improved total outcome.
Teleradiology in neurosurgery: experience in 1024 cases
Authors: Kreutzer Juergen , Akutsu Hiroyoshi , Fahlbusch Rudolf , Buchfelder Michael , Nimsky Christopher
Published: March 2008

Summary

Between June 1995 and June 2000 teleradiology was performed in 1024 neurosurgical cases (945 patients). An analogue image transfer system was used for presentation of computed tomography (CT) and magnetic resonance imaging (MRI) scans from seven referring hospitals in southern Germany. The system used a 19,200 baud modem connection via the ordinary telephone network. The diagnoses on presentation were intracerebral haematoma (50%), trauma (27%), subarachnoid haemorrhage (4%), stroke (5%) and others (14%). Retrospective analysis showed that in 67% of cases admission and therefore ground-based transportation of the patients to our neurosurgical centre was not necessary for different reasons (moribund status, no surgical intervention required or no neurosurgical problem at all). If each patient had been transferred, then the potential savings for ground transportation were €339.93 per case (with accompanying physician of the affiliated hospital) or €373.96 per case (with accompanying experienced ICU physician), respectively (€1 is US$1.4). The total cost of the image transfer system for all eight hospitals was €96,000; this was amortised after 282 teleconsultations, which occurred after 15 months of usage. A simple teleradiology system in neurosurgery enables rapid and reliable telephone consultations, mainly on patients with trauma, stroke and intracerebral haematoma at low cost.
Use of telemedicine for haemodialysis: perceptions of patients and health-care providers, and clinical effects
Authors: Whitten Pamela , Buis Lorraine
Published: March 2008

Summary

In Michigan, the use of telemedicine for dialysis patients began in three centres in 2005. A total of 747 clinical consultations was conducted in the following 22 months. Telephone surveys were conducted with 34 patients and four providers. The patients and providers all had positive perceptions of the telemedicine system and the care that was delivered. Most of the clinical measures of the patients met or exceeded the recommendations made by Renal Network 11. In addition to the clinical work, the telemedicine equipment was used for educational events. Twenty-six professional educational events were provided with a total audience of 105 individuals, and 35 administrative meetings were provided with 286 staff members in attendance. The study showed that patients and providers could participate in educational events that might not be available locally. Despite the success of dialysis telemedicine, the Marquette General Health System discontinued its use in 2007 when the Center for Medicare and Medicaid Services re-affirmed that dialysis centres were not approved sites for telemedicine.
Home-based telehealth: a review and meta-analysis
Authors: DelliFraine Jami L , Dansky Kathryn H
Published: March 2008

Summary

We conducted a systematic review to identify studies on the effect of home telehealth on clinical care outcomes. The search was restricted to peer-reviewed publications (published between 2001 and 2007) about studies conducted in home or residential settings. The search yielded 154 potential articles and dissertations. A total of 29 articles met the inclusion criteria and were included in a meta-analysis. The weighted mean effect size for the overall meta-analysis was 0.50, and the z-statistic was 3.0, indicating that telehealth had a moderate, positive and significant effect ( P ≤ 0.01) on clinical outcomes. Subanalyses also indicated positive significant effects of telehealth for some disease categories (heart disease and psychiatric conditions), but not others (diabetes), patient populations and telehealth interventions. Overall, the meta-analysis indicated that telehealth positively affects clinical outcomes of care, even in different patient populations.
Use of telemedicine for pre-implant dental assessment – a comparative study
Authors: Nickenig Hans-Joachim , Wichmann Manfred , Schlegel Andreas , Eitner Stephan
Published: March 2008

Summary

We evaluated real-time telemedicine for exchanging expert opinions in the area of pre-implant dental assessment. From 2003 to 2005, every tenth patient at the armed forces’ dental clinic in Cologne-Wahn seeking implant counselling was discussed via videoconference (intervention group, n = 85). Indications, prosthodontic options, the required number of implants and implant positions were determined. The mean time required for the videoconferences was 3.5 min (range 1.0–9.5). In the control group ( n = 772), the implant consultation was performed based on existing records, without using telemedicine. In three cases (3%), a basic change in the prosthodontic concept was required as compared to the telemedicine plan; in the control group, the concept changed in 7% of cases. The changes in the number and position of implants during therapy were also similar in the two groups. The results showed that telemedicine permitted satisfactory preoperative evaluation of the implantation operation.
Pre-admission orthopaedic occupational therapy home visits conducted using the Internet
Authors: Hoffmann Tammy , Russell Trevor
Published: March 2008

Summary

We evaluated the feasibility and accuracy of conducting occupational therapy home visits using the Internet. Studies were conducted at the homes of 40 patients who were scheduled to undergo a total hip or knee replacement: home visits were conducted, on the same day, by both a face-to-face therapist and an online therapist. The online therapist conducted the visit via a low-speed, dial-up Internet connection using a specially developed telerehabilitation system. This system combines real-time videoconferencing (320 x 240 pixel resolution) with a suite of calibrated assessment tools which the operator can use to measure real-scale angular displacement/velocity and linear distances during the videoconference. Both therapists completed a home environment questionnaire, assessed patients' transfer ability and measured the heights of six objects/pieces of furniture. For the questionnaire items which related to variables in the home environment, the mean percentage exact agreement was 98.9% (SD 2.6; range 90–100), while there was 100% agreement on the items related to transfers. The mean absolute difference in measured heights between the two therapists ranged from 0.1–3.3 cm. The results suggest that conducting pre-admission orthopaedic occupational therapy home visits via the Internet is both feasible and accurate.
Decoding CODECs
Authors: Gantenbein Rex E , Robinson Barbara J
Published: March 2008

Summary

A codec is the mechanism by which video and audio signals are compressed to conserve bandwidth before transmission across a telecommunication network. It may be implemented either in hardware or software. In the past, manufacturers sometimes used proprietary codecs that were incompatible with those from other manufacturers. As network usage became more widespread, however, it became clear that standards were needed to permit interoperability between equipment from different manufacturers. Regardless of the coding standards employed, the primary concerns for the user of a codec system are the quality of the audio and video transmitted. How does one decide what kind of codec to use? For telehealth applications, good quality is important, so it is best to look at products from established manufacturers. Ultimately, the choice of a codec for telehealth depends primarily on the trade-offs between quality, cost, bandwidth requirements and interoperability required by the application(s) for the system, and the environment in which it will be used.
Mental health services for children and youth: a survey of physicians' knowledge, attitudes and use of telehealth services
Authors: Cloutier Paula , Cappelli Mario , Glennie J Elizabeth , Keresztes Christian
Published: March 2008

Summary

Rural physicians in Ontario, whose practice included children, were surveyed on their awareness, attitudes and use of telemental health services for children and young people in their region. Of 95 rural physicians, 70 completed and returned the telehealth section of the survey (74% response rate). The survey comprised 14 questions. Only 27% of responders were aware of the available videoconferencing services. The proportion of physicians who reported having referred patients for the various mental health services through videoconferencing was 0–24%. The proportion of physicians who reported that they would refer patients through videoconferencing was 55–92%. Reduced travel time and care provided closer to home were seen as the primary benefits of referring patients to mental health services through videoconferencing. Unclear referral patterns and technology compromises were seen as limitations of referring patients to videoconferencing. Access to rural populations and improved access to patients were seen as benefits to practice, and undeveloped remuneration procedures as the primary limitation. Promotion may be important to successful implementation of telemental health services for children and young people.
Eusèbe de Césarée face à l'essor de la littérature chrétienne au IIe siècle: Propos pour un commentaire du IVe livre de l'Histoire Ecclésiastique
Authors: Perrone Lorenzo
Published: March 2008

The article presents the current work on a commentary about the 4th book of Eusebius, Historia Ecclesiastica. After presenting the most important editions and bibliographical tools the article proposes the need of a detailed chronicle gathering together all the dates of the Historia Ecclesiastica, the Chronica and of other informations (e.g. about the emperors). For the analysis of language the article shows the rich vocabulary of Eusebius and the high quality of stylistic variation. The use of sources has to be analysed in a very careful manner. So, for example, the Martyrium Polycarpi, is not simply used, but Eusebius mixed two extracts with a kind of paraphrase. The comparison of the Martyrium Polycarpi with the text of book IV shows the “re-écriture” of Eusebius. So the article ends stating the several methods and strategies which should be taken into account for a commentary about Eusebius, Historia Ecclesiastica.
Modeling the influence of environmental heterogeneity on heavy metal exposure concentrations for terrestrial vertebrates in river floodplains
Authors: Schipper Aafke M , Loos Mark , Ragas Ad M. J , Lopes João P. C , Nolte Boris T , Wijnhoven Sander , Leuven Rob S. E. W
Published: March 2008

To analyze the influence of environmental heterogeneity on heavy metal exposure concentrations for terrestrial vertebrates in river floodplains, a spatially explicit exposure model has been constructed (SpaCE-model: Spatially explicit cumulative exposure model). This model simulates the environmental use of individual organisms by selecting model cells to be foraged in within a multicelled, heterogeneous landscape. Exposure durations and exposure concentrations are calculated for the selected cells, whereby exposure concentrations are dependent on the availability and contaminant concentrations of different diet items in each cell. The model was applied to a selection of 10 terrestrial vertebrate species, including six small mammalian and four top predator species. It was parameterized for cadmium contamination in a 285-ha, embanked floodplain area along the Rhine River in The Netherlands. Simulations of 1,000 individuals for each species resulted in intraspecies variation in exposure concentrations of between 11 and 39%, with the smallest values generally corresponding to the species with the largest home ranges. Comparison of the model results with cadmium concentrations measured in four of the species from the study area showed that the predicted variation accounted for 12 to 16% of the variation in the measurements. This indicates that environmental heterogeneity governs a minor part of the variation in metal exposure concentrations that can actually be observed in river floodplains.
Nanowastes and the environment: Using mercury as an example pollutant to assess the environmental fate of chemicals adsorbed onto manufactured nanomaterials
Authors: Gao Jie , Bonzongo Jean-Claude J , Bitton Gabriel , Li Ying , Wu Chang-Yu
Published: March 2008

Emerging nanotechnologies hold great promise for creating new means of detecting pollutants, cleaning polluted waste streams, and recovering materials before they become wastes, thereby protecting environmental quality. Studies focusing on the different advantages of nanoscience and nanotechnology abound in the literature, but less research effort seems to be directed toward studying the fate and potential impacts of wastes that will be generated by this technology. Using a combination of biogeochemical and toxicological methods, we conducted a preliminary investigation of the potential environmental fate of Hg as an example pollutant bound to nanomaterials used in treatment of gas effluents. Methylation of Hg sorbed onto SiO2-TiO2 nano-composites was used as a proxy for Hg bioavailability to sedimentary microorganisms, and the FluoroMetPLATE™ assay was used to assess the toxicity of both virgin and Hg-loaded SiO2-TiO2 nanocomposites. Our results show that the bioavailability of Hg sorbed onto SiO2-TiO2 nanocomposites to sedimentary microorganisms is pH dependent, with decreasing reaction rates as the pH increases from 4 to 6. Toxicity tests conducted using liquid extracts obtained by leaching of Hg-loaded SiO2-TiO2 nanocomposites with the synthetic precipitation leaching procedure solution showed an average inhibition of 84% (vs 57% for virgin SiO2-TiO2 nanocomposites). These results suggest that Hg sorbed onto engineered nanoparticles could become bioavailable and toxic if introduced into natural systems. Accordingly, studies focusing on the environmental implications of nanomaterials should include determination of the fate and impacts of pollutants that enter the environment bound to engineered nanomaterials.
Using fluorescent aromatic compounds in bile from juvenile salmonids to predict exposure to polycyclic aromatic hydrocarbons
Authors: Meador James P , Buzitis Jon , Bravo Claudia F
Published: March 2008

We provide data from four different studies in which fish were fed polycyclic aromatic hydrocarbons (PAHs) that were used to develop a predictive relationship between dose (μg/g fish/d) and metabolites of PAHs in bile. Juvenile salmonids were fed various doses of total PAH that were applied as a mixture to fish pellets. The number of PAHs in each mixture ranged from 10 to 21 different low- and high-molecular-weight compounds, and their relative proportions and abundance were based on stomach concentrations observed for field-collected fish. Although we examined both the phenanthrene (PHN) and benzo[a]pyrene signals for the fluorescent aromatic compounds (FACs) in bile, the PHN signal exhibited the highest correlation and was considered to be the better choice for predicting exposure. A large database of PHN FAC values for field-collected fish was examined and used to predict dose by the method of inverse prediction. The goal of the present study was to develop a predictive relationship that would allow estimation of an exposure dose for an observed value of PHN FACs from juvenile salmonids sampled in the field. This dose would then be used to estimate adverse effects based on toxicity results from laboratory studies. Additional analyses were performed to determine ventilation doses from water concentrations of total PAH and then relate those to PHN FAC values.
Estrogenic effects of polychlorinated biphenyls and relation to cytochrome P4501A activity in the endangered goodeid fishAmeca splendens
Authors: Vega-López Armando , Jiménez-Orozco F. Alejandro , Ramón-Gallegos Eva , García-Latorre Ethel , Domínguez-López M. Lilia
Published: March 2008

The present study examines the relationships between cytochrome P4501A (CYP1A) activity and vitellogenin (VTG) induction in Ameca splendens elicited by a polychlorinated biphenyl (PCB) mixture. Ethoxyresorufin-O-deethylase (EROD) activity, mRNA levels of VTG, and VTG induction were evaluated in male and female fish exposed for 1, 2, 4, 8, and 16 d to a commercial PCB mixture. Polychlorinated biphenyls induced higher EROD in both sexes and this induction was higher in females than in males. Maximum EROD and VTG induction occurred on day 1 in females, while in males these maxima occurred on days 8 and 16. A correlation between EROD and VTG induction was found only in males (p < 0.001), and VTG induction was also higher in males than in females (p < 0.01). Exposure to PCBs elicited increases in VTG expression and induction over time in males, while in females these decreased at the end of the exposure period. Deficiencies in the feedback mechanisms of male A. splendens exposed in the wild to xenoestrogens such as PCBs have probably contributed to alter the sex ratio of wild populations of this species.
Uncertainty analysis of dioxin-like polychlorinated biphenyls–related toxic equivalents in fish
Authors: Bhavsar Satyendra P , Hayton Alan , Jackson Donald A
Published: March 2008

The toxic equivalent (TEQ) concept is widely used to assess toxicity potential of a dioxin-like chemical mixture. The TEQ approach converts concentrations of various dioxin-like compounds into a single concentration that is toxicologically equivalent to the most toxic dioxin compound, 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), using toxic equivalency factors (TEFs). It has been shown that in the absence of costly measurements of dioxin-like polychlorinated biphenyls (dl-PCBs) in fish, relatively inexpensive measurements of total PCB can be utilized to estimate dl-PCB–related TEQ (i.e., TEQdl-PCB). The present study assesses the impacts of uncertainties in dl-PCB measurements and estimates, and mammalian TEFs on TEQdl-PCB using the Monte Carlo technique. The analysis suggests that measurement errors for dl-PCBs translate into up to 1.3-fold uncertainty in TEQdl-PCB, while uncertainties in estimates of dl-PCBs generally produce up to a threefold uncertainty in TEQdl-PCB. In contrast, the uncertainty due to TEFs normally ranges 10- to 13-fold and spans over 30- to 40-fold under extreme cases. For 2005 TEFs, PCB-126 is the dominating contributor to uncertainty in TEQdl-PCB. When we considered uncertainties in the TEFs and estimated dl-PCB concentrations simultaneously, there was little increase in uncertainty in TEQdl-PCB that was already produced by the TEFs only. These results indicate that the dl-PCB composition in fish and/or the relationship between total PCB and TEQdl-PCB can be utilized to estimate TEQdl-PCB with reasonable confidence.
Development of a simulation–optimization model for multiphase systems in the subsurface: a challenge to real-world simulation–optimization
Authors: Kobayashi Kenichiro , Hinkelmann Reinhard , Helmig Rainer
Published: March 2008

The main purpose of this paper is to demonstrate the capability of a new simulation–optimization model especially tailored to investigate the optimal management strategy of a closed coal mine in the Ruhr, Germany. This paper deals with the multiphase/multicomponent flow simulation; the optimization model (simulated annealing); the mesh generation function; the coupling of them; and the use of a parallel computer. Firstly, a mesh generation function is included in the total procedure for the modelling of complex system configurations often required when the real-world problem is dealt with. The multiphase/multicomponent flow simulator can simulate not only groundwater flow and a tracer in it but also the multiphase systems (e.g. gas–water, gas–water–NAPL system). Moreover, a parallelization strategy for the optimization procedure is proposed and implemented to overcome the enormous CPU time problem always tagged to real-world simulation–optimizations. This strategy succeeded in enhancing the efficiency of the overall procedure almost linearly by the number of the processors in a parallel computer. This model is then applied to study how to install the passive extraction wells for controlling the migration of methane continuously desorbed from coal seams inside the closed coal mine in the Ruhr, Germany. The general rule proposed as the result of the application is rather simple although it is considered very useful in many practices of coal mining operations. This paper briefly outlines the overall procedure.
Historic sediment accumulation rates in Karlskärsviken, a bay of Lake Mälaren, Sweden
Authors: Olli Gull
Published: March 2008

Historic sediment accumulation rate development was investigated in Karlskärsviken, a bay of Lake Mälaren, by dating of sediments in cores taken from the bay. The Lake Mälaren transition period from brackish water to freshwater was determined by diatom analysis and for modern times by fly-ash (SCP) and caesium isotope Cs-137 analyses. Results show that in the long period from medieval times to about 1950, the sediment accumulation rate increased to about double in the outer section of the bay, but only by about 33% in the near shore. After that, new farmland was drained by a ditch dug in 1951 with its outlet in Karlskärsviken, which enlarged the bay catchment area by 100%, and a marina and a public beach were constructed in 1953. These catchment system changes increased considerably the inflow of particles to Karlskärsviken and the sediment accumulation in the bay, directly and mostly in the near shore, but also with some and longer term effects further out in the bay. In later times, as the ditch became overgrown by reeds and bushes, the sedimentation rate decreased again in the near shore, while it continued to increase further out in the bay. These results indicate that even relatively small and common catchment enterprises may considerably affect sediment transport to recipient bay waters.
Dating stratigraphic variations of ions and oxygen isotopes in a high-altitude snowpack by comparison with daily variations of precipitation chemistry at a low-altitude site
Authors: Theakstone W.H.
Published: March 2008

Daily precipitation at Tustervatn (65°83′N, 13°92′E, 439 m above sea level) was analysed for ions and oxygen isotopes. Seven-day air mass trajectories provided information about the precipitation source and history. The highest Na+ loads were associated with air masses which had crossed the Norwegian Sea and the highest non-sea-salt SO42− loads with trajectories crossing Scandinavia or the United Kingdom; high SO42− loads in late April reflected decreasing snow cover. Trajectories from the Arctic basin resulted in the lowest δ18O values. During the winter, 4.8 m of snow accumulated at 1470 m above sea level on the glacier Austre Okstindbreen, 25 km north-east of Tustervatn. Mean ionic concentrations were lower than at Tustervatn, but loads were higher, as the total precipitation was three times greater. At both sites, ionic loads were closely related to ionic concentrations but not to sample water-equivalent values/precipitation amounts. Dates could be assigned to much of the snowpack on the basis of similarities between its chemical stratigraphy and temporal variations of precipitation chemistry at Tustervatn. Examination of the influence of individual storms on δ18O variations and the relationship between those variations and atmospheric circulation patterns has potential importance in relation to understanding past, present and possible future climatic conditions.
Metal Analysis
Authors: Wrobel Katarzyna , Wrobel Kazimierz , Caruso Joseph A.
Published: March 2008

Measuring the concentration levels of trace and ultratrace elements in different samples is an important analytical task in environmental, biological, clinical, as well as industrial studies. Furthermore, the increasing recognition of species‐dependent behavior of elements in a given system has imposed the need for speciation analysis. Thus, the identification and/or quantification of individual compounds is required for elements in their naturally occurring forms, those produced and/or emitted from different anthropogenic activities, as well as the products of species degradation or biotransformation. The two most commonly used tools to deal with such analyses are plasma‐spectrometry techniques, namely inductively coupled plasma optical emission spectrometry (ICP‐OES) and inductively coupled plasma mass spectrometry (ICP‐MS). The suitability of these two techniques relies on their multielemental capabilities, high selectivity, wide dynamic range, high sample throughput, absence of chemical interferences, and easy coupling with different separation techniques. Consequently, applications of these techniques encompass both the determination of total element concentration and the specific detection of elements in different speciation schemes. In this article, the technical background of ICP‐OES and ICP‐MS is introduced, highlighting the capabilities and limitations of each technique. Different sample introduction systems are briefly presented and some applications for element analysis in inorganic and organometallic chemistry are reviewed.
Nuclear Magnetic Resonance (
NMR
) Spectroscopy of Metallobiomolecules
Authors: Bren Kara L.
Published: March 2008

Nuclear magnetic resonance (NMR) spectroscopy provides information on the structure and dynamics of metallobiomolecules at atomic resolution. A range of metal‐binding sites in biomolecules can be studied by NMR, although the methods used require consideration of the properties of the metal site. Diamagnetic metal‐binding sites are probed using conventional NMR approaches appropriate for analyzing interactions between ions and macromolecules. Weak metal binding as is common in RNAs may require use of mimics that bind more strongly and/or that provide a specific spectroscopic handle. Paramagnetic metals induce hyperfine shifting and linebroadening that serve as signals of metal binding, but may also require adjustments to standard NMR methodologies. Hyperfine shifting takes place through scalar or dipolar mechanisms, and these effects in turn reveal details of metal site structure and metal electronic structure. Paramagnetic effects on chemical shifts are also used to refine structures of metallobiomolecules. Resonance broadening resulting from the hyperfine interaction is related to unpaired electron–nucleus distance as well as properties of the metal ion and thus can be a restraint on structure. The high magnetic anisotropy of some paramagnetic biomolecules can cause the molecule to take a preferential orientation within the applied magnetic field to allow observation of residual dipolar couplings, which reveal relative angular orientations of bond vectors. The study of the many effects of paramagnetic centers on NMR spectra has advanced the field of biomolecular solution structure determination as these efforts have introduced new restraints used in calculating structures. NMR is also valuable for analyzing biomolecule dynamics and chemical exchange processes. A related application is analysis of interactions between metallobiomolecules and ligands, or other macromolecules. Application of NMR to metallobiomolecules has provided a means to study phenomena difficult to observe using other methods such as interactions between proteins, electron self‐exchange reactions, and biomolecule dynamics over a wide range of time scales. NMR methodology continues to advance rapidly and is expected to continue to exert a large influence on our understanding of metal sites in biomolecules.
Perturbed Angular Correlations of γ‐rays (PAC) Spectroscopy
Authors: Hemmingsen Lars , Butz Tilman
Published: March 2008

In this article, we give an elementary introduction to the theory and applications of perturbed angular correlation of γ‐rays (PAC) spectroscopy. In most applications in bioinorganic and inorganic chemistry the nuclear quadrupole interaction (NQI) is measured, providing a spectroscopic fingerprint of the local electronic and molecular structure and dynamics at the PAC probe site. The focus is on selected illustrative applications of PAC spectroscopy in bioinorganic chemistry: (i) local structure at metal ion binding sites in the bacterial mercury sensor MerR; de novo designed proteins; alcohol dehydrogenase–pH dependence; carboxypeptidase A—crystalline state versus solution; and carboxypeptidase A–during the hydrolysis of substrate; (ii) trapping intermediates in reactions using rapid freeze quenching; (iii) in vivo experiments on Cd(II) binding to biomolecules in cyanobacteria; (iv) cooperativity of metal ion binding in multinuclear sites; (v) dynamics of protein folding; (vi) rotational diffusion of biomolecules as a tool to monitor protein–protein interactions; (vii) exchange dynamics; and (viii) internal dynamics in proteins.

Examples from inorganic chemistry and solid state physics are included for cases where the information derived is different from that already presented in the examples from bioinorganic chemistry: (i) magnetic properties of metals; (ii) defects trapped by the impurity PAC probe atom; (iii) temperature and pressure dependence of the EFG in metals; (iv) amorphous metals, alloys and internal oxidation; (v) metal surfaces and interfaces; (vi) semiconductors; (vii) phase transitions; (viii) charge density waves in transition metal dichalcogenides; (ix) intercalation reactions in 2H‐TaS2; (x) structure and bonding; (xi) single crystal experiments.
Rapid Scan, Stopped‐Flow Kinetics
Authors: Wang Rui‐Yong
Published: March 2008

One of the most frequently used rapid kinetics techniques is the stopped‐flow method. A major strength of rapid mixing methods is that they can be readily combined with a wide range of detection methods. Applications of stopped‐flow techniques, mainly stopped‐flow absorbance and fluorescence spectrometry, in the fields of inorganic and bioinorganic chemistry include kinetic measurement of ligand substitution, ligand binding and dissociation, redox reactions, and so on. The kinetic and thermodynamic parameters can be calculated with the aid of stopped‐flow methods. The general procedures for kinetic and thermodynamic studies by using stopped‐flow techniques are also discussed.
Electron Transfer: Chemical Roles of Water
Authors: Balabin Ilya A. , Beratan David N. , Skourtis Spiros S.
Published: March 2008

Water plays multiple roles in biological electron transfer (ET): energy bath, polarizable medium that defines the reaction coordinate, electronic coupling bridge, and intimate participant in molecular recognition. This article explores these many faces of water in ET. Links are drawn to reactions in photosynthesis, oxidative phosphorylation, proton‐coupled ET, and DNA damage and repair.
Natural Products in Plants: Chemical Diversity
Authors: Leslie Gunatilaka A.
Published: March 2008

Plants contain numerous natural products (secondary metabolites) that may not participate directly in their growth and development but play an important role in ecological interactions with other organisms. Despite immense chemical diversity, which originates from simple carbohydrates produced because of photosynthesis, plant natural products are formed from only a few biosynthetic building blocks that consist of acetate, mevalonate, and shikimate. These basic building blocks undergo a variety of biosynthetic transformations and combinations that lead to numerous classes of plant natural products including, but not limited to, carbohydrates, fatty acids and their esters, aromatic polyketides (phenols and quinones), terpenoids and steroids, phenyl propanoids (lignans and lignin, coumarins, flavonoids, and isoflavonoids), and alkaloids. Summarized in this article are representative members of these important classes of plant natural products with special emphasis on their chemical diversity. The article concludes with a brief discussion on recent methods for the maximization of chemical diversity and the production of natural products from plants.