bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Situ Monitoring of Vapor Phase TCE Using a Chemiresistor Microchemical Sensor
Authors: Ho Clifford K. , Lohrstorfer Charles F. 
Published: February 2007

AbstractA chemiresistor microchemical sensor has been developed to detect and monitor volatile organic compounds in unsaturated and saturated subsurface environments. A controlled study was conducted at the HAZMAT Spill Center at the Nevada Test Site, where the sensor was tested under a range of temperature, moisture, and trichloroethylene (TCE) concentrations. The sensor responded rapidly when exposed to TCE placed in sand, and it also responded to decreases in TCE vapor concentration when clean air was vented through the system. Variations in temperature and water vapor concentration impacted baseline chemiresistor signals, but at high TCE concentrations the sensor response was dominated by the TCE exposure. Test results showed that the detection limit of the chemiresistor to TCE vapor in the presence of fluctuating environmental variables (i.e., temperature and water vapor concentration) was on the order of 1000 parts per million by volume, which is about an order of magnitude higher than values obtained in controlled laboratory environments. Automated temperature control and preconcentration is recommended to improve the stability and sensitivity of the chemiresistor sensor.
CRT‐Hole Closure
Authors: Noce Thomas E. , Holzer Thomas L. 
Published: February 2007

AbstractThe long‐term stability of deep holes 1.75 inches. (4.4 cm) in diameter by 98.4 feet (30 m) created by cone penetration testing (CPT) was monitored at a site in California underlain by Holocene and Pleistocene age alluvial fan deposits. Portions of the holes remained open both below and above the 28.6‐foot (8.7 m)‐deep water table for approximately three years, when the experiment was terminated. Hole closure appears to be a very slow process that may take decades in the stiff soils studied here. Other experience suggests holes in softer soils may also remain open. Thus, despite their small diameter, CPT holes may remain open for years and provide paths for rapid migration of contaminants. The observations confirm the need to grout holes created by CPT soundings as well as other direct‐push techniques in areas where protection of shallow ground water is important.
Modeling Volatile Chemical Transport, Biodecay, and Emission to Indoor Air
Authors: Parker Jack C. 
Published: February 2007

AbstractA model is presented for estimating vapor concentrations in buildings because of volatilization from soil contaminated by non‐ aqueous phase liquids (NAPL) or from dissolved contaminants in ground water. The model considers source depletion, diffusive‐ dispersive transport of the contaminant of concern (COC) and of oxygen and oxygen‐limited COC biodecay. Diffusive‐advective transport through foundations and vapor losses caused by foundation cross‐flow are considered. Competitive oxygen use by various species is assumed to be proportional to the product of the average dissolved‐phase species concentration and a biopreference factor. Laboratory and field data indicate the biopreference factor to be proportional to the organic carbon partition coefficient for the fuel hydrocarbons studied. Predicted indoor air concentrations were sensitive to soil type and subbase permeability. Lower concentrations were predicted for buildings with shallow foundations caused by flushing of contaminants by cross‐flow. NAPL source depletion had a large impact on average exposure concentration. Barometric pumping had a minor effect on indoor air emissions for the conditions studied. Risk‐based soil cleanup levels were much lower when biodecay was considered because of the existence of a threshold source concentration below which no emissions occur. Computed cleanup levels at NAPL‐contaminated sites were strongly dependent on total petroleum hydrocarbon (TPH) content and COC soil concentration. The model was applied to two field sites with gasoline‐contaminated ground water. Confidence limits of predicted indoor air concentrations spanned approximately two orders of magnitude considering uncertainty in model parameters. Measured contaminant concentrations in indoor air were within model‐predicted confidence limits.
Bentonite as a Natural Adsorbent for the Sorption of Iron from the Ground Water Exploited from Aswan Area, Egypt
Authors: Taha Gharib M. , Elmagd Kamal Abou 
Published: February 2007

AbstractSorption of dissolved Fe2+ on bentonite was studied using a batch technique. The distribution coefficient, Kd, was evaluated for a bentonite‐iron system as a function of contact time, pH, sorbent and sorbate concentrations, and temperature. Sorption results were interpreted in terms of Freundlich's and Langmuir's equations. Thermodynamic parameters for the sorption system were determined at three temperatures: 298°, 308°, and 318°K. The values of ΔH°(‐4.0 kjmol−1) and ΔG°(‐2.46 Kjmol−1) at 298°K (25°C) suggest that sorption of iron on bentonite is an exothermic and a spontaneous process. The ΔG° value became less negative at higher temperatures and, therefore, less iron was sorbed at higher temperatures. The desorption studies with 0.01M CaCl2 and deionized water at iron loading on bentonite showed that more than 90 wt% of the iron is irreversibly sorbed, probably due to the fixation of the iron by isomorphous replacement in the crystal lattice of the sorbent.
Sampling Plan Optimization: A Data Review and Sampling Frequency Evaluation Process
Authors: Ridley Maureen , MacQueen Donald 
Published: February 2007

AbstractLawrence Livermore National Laboratory (LLNL) uses a cost‐effective sampling (CES) methodology to evaluate and review ground water contaminant data and optimize the site's ground water monitoring plan. The CES methodology is part of LLNL's regulatory approved compliance monitoring plan (Lamarre et al. 1996). It allows LLNL to adjust the ground water sampling plan every quarter in response to changing conditions at the site. Since the use of the CES methodology has been approved by the appropriate regulatory agencies, such adjustments do not need additional regulatory approval. This permits LLNL to respond more quickly to changing conditions. The CES methodology bases the sampling frequency for each location on trend, variability, and magnitude statistics describing the contaminants at that location, and on the input of the technical staff (hydrologists, chemists, statisticians, and project leaders). After initial setup is complete, each application of CES takes only a few days for as many as 400 wells. Effective use of the CES methodology requires sufficient data, an understanding of contaminant transport at the site, and an adequate number of monitoring wells downgradient of the contamination. The initial implementation of CES at LLNL in 1992 produced a 40% reduction in the required number of annual routine ground water samples at LLNL. This has saved LLNL $390,000 annually in sampling, analysis, and data management costs.
Attenuation of Two Estrogen Compounds in Aquifer Materials Supplemented with Sewage Effluent
Authors: Ying Guang‐Guo , Kookana Rai S. , Dillon Peter 
Published: February 2007

AbstractAquifer storage and recovery (ASR) is an emerging and effective management technique in reclaiming and reusing waste water. During ASR, attenuation processes such as sorption and degradation may play an important role in removing trace organic contaminants in injected waste water. This study mainly investigated the role of treated sewage effluent injectant (the waste water injected into the aquifer) on degradation of two endocrine disrupting compounds, 17β‐estradiol (E2) and 17α‐ethynylestradiol (EE2), in the laboratory by comparing their behavior in incubation media&mdash;aquifer sediment/ground water slurry from the Bolivar experimental ASR site in South Australia and sediment/effluent slurry. Biodegradation of the two compounds in the sediment/ground water media (1:1, w/w) and in the sediment/effluent media (1:1, w/w) were conducted under aerobic and anaerobic conditions at 20°C. In both incubation media, E2 showed a rapid biodegradation with a DT50 value (time for 50% loss) of ∼2 days under aerobic conditions. E2 degraded slowly in both aquifer media under anaerobic conditions; however, the anaerobic degradation was noted to be somewhat faster in the sediment/effluent media. In contrast, EE2 was found to be resistant to biodegradation and remained almost unchanged within 70 days under anaerobic conditions in both incubation media. The mobility of the two compounds in the aquifer would depend on their sorption. The sorption coefficients measured on the aquifer sediment were 7.7 ± 3.4 L/kg for E2 and 10.6 ± 5.1 L/kg for EE2 using batch equilibration methods. The corresponding retardation factors were calculated to be 25 for E2 and 34 for EE2 based on the physical properties of the aquifer material in the Bolivar ASR site. This study showed that while E2 has modest sorption affinity for aquifer material, it is rapidly biodegraded with or without the supplement of effluent under aerobic conditions. Under anaerobic conditions, the relative rate of E2 degradation was slightly enhanced due to the presence of effluent in the incubation media. EE2 on the other hand was found to be persistent in this study under both aerobic and anaerobic conditions, as well as in the presence of effluent.
Reed bunting (Emberiza schoeniclus) males sing an 'all-clear' signal to their incubating females
Authors: Wingelmaier Katja , Nemeth Erwin , Winkler Hans 
Published: February 2007

AbstractWhile sexual functions of birdsong have been intensively investigated, non-sexual functions have received less attention. After pair formation males may sing to communicate with their established mates. Song aimed at incubating and feeding females could serve as an 'all-clear' signal, showing that there is no risk of predation and that it is safe for the female to exit the nest or to feed the young. Females should therefore preferentially leave nests when mates are singing nearby. Additionally, a vigilant male near the nest site could protect the brood from potential risks like predation and females could stay away longer for foraging. In this study, we investigated aspects of male singing activity of reed buntings (Emberiza schoeniclus) during incubation and feeding of nestlings after pair formation. Exits of incubating females from the nest occurred significantly more often than expected during male song output. When their mates were singing at high rates, females stayed away longer for incubation breaks. During the nestling period we found a high variation in male song output. Males that sang more fed their young significantly less. This suggests that time devoted to singing limits other activities such as feeding of offspring. Male reed buntings could choose different strategies for paternal investment: They either feed at high rates or they sing more to signal their vigilance. Another reason for this trade-off might be a conflict between paternal investment and territory defence or extrapair behaviour. However, even if male song after pairing has additional sexual functions, we suggest that non-sexually selected functions may be more common than expected.
Do turning biases by the 7-spot ladybird, Coccinella septempunctata, increase their foraging efficiency?
Authors: Hassall Mark , Turner John , Girling Robbie 
Published: February 2007

AbstractThe hypothesis that foraging male and female Coccinella septempunctata L. would exhibit a turning bias when walking along a branched linear wire in a Y-maze was tested. Individuals were placed repeatedly in the maze. Approximately 45% of all individuals tested displayed significant turning biases, with a similar number of individuals biased to the left and right. In the maze right-handed individuals turned right at 84.4% of turns and the left-handed individuals turned left at 80.2% of turns. A model of the searching efficiency of C. septempunctata in dichotomous branched environments showed that model coccinellids with greater turning biases discovered a higher proportion of the plant for a given number of searches than those with no bias. A modification of the model to investigate foraging efficiency, by calculating the mean time taken by individuals to find randomly distributed aphid patches, suggested that on four different sizes of plants, with a variety of aphid patch densities, implementing a turning bias was a significantly more efficient foraging strategy than no bias. In general the benefits to foraging of implementing a turning bias increased with the degree of the bias. It may be beneficial for individuals in highly complex branched environments to have a turning bias slightly lower than 100% in order to benefit from increased foraging efficiency without walking in circles. Foraging bias benefits increased with increasing plant size and decreasing aphid density. In comparisons of two different plant morphologies, one with a straight stem and side branches and one with a symmetrically branched morphology, there were few significant differences in the effects of turning biases on foraging efficiency between morphologies.
Dasatinib or high-dose imatinib for chronic-phase chronic myeloid leukemia after failure of first-line imatinib: a randomized phase 2 trial
Authors: Kantarjian Hagop , Pasquini Ricardo , Hamerschlak Nelson , Rousselot Philippe , Holowiecki Jerzy , Jootar Saengsuree , Robak Tadeusz , Khoroshko Nina , Masszi Tamas , Skotnicki Aleksander , Hellmann Andrzej , Zaritsky Andrey , Golenkov Anatoly , Radich Jerald , Hughes Timothy , Countouriotis Athena , Shah Neil 
Published: February 2007

AbstractTherapeutic options for chronic myelogenous leukemia (CML) resistant to 400 to 600 mg imatinib are limited. Escalating imatinib doses may overcome resistance. Dasatinib, a significantly more potent inhibitor of BCR-ABL, is safe and effective in this population. Patients with imatinib-resistant chronic-phase (CP) CML were randomized 2:1 to 140 mg dasatinib (n = 101) or 800 mg imatinib (n = 49). With a median follow up of 15 months, complete hematologic responses were observed in 93% and 82% of patients receiving dasatinib and high-dose imatinib (P = .034), respectively. Dasatinib resulted in higher major cytogenetic response rates (52%) than high-dose imatinib (33%) (P = .023); this included complete cytogenetic response in 40% and 16% (P = .004). Major molecular responses were also more frequent with dasatinib (16% versus 4%; P = 0.038). Treatment failure (hazard ratio [HR], 0.16; P < .001) and progression-free survival (HR, 0.14; P < .001) both favored dasatinib. Superficial edema (42% versus 15%) and fluid retention (45% versus 30%) were more prevalent with imatinib; pleural effusion was more common with dasatinib (17% versus 0%). Grade 3 to 4 nonhematologic toxicity was minimal. Cytopenias were more frequent and severe with dasatinib. Dasatinib represents a safe and effective therapy for CP-CML resistant to conventional imatinib doses with improved cytogenetic and molecular response rates and progression-free survival relative to high-dose imatinib.
β-Catenin stabilization stalls the transition from double-positive to single-positive stage and predisposes thymocytes to malignant transformation
Authors: Guo Zhuyan , Dose Marei , Kovalovsky Damian , Chang Rui , O'Neil Jennifer , Look A. Thomas , von Boehmer Harald , Khazaie Khashayarsha , Gounari Fotini 
Published: February 2007

AbstractActivation of β-catenin has been causatively linked to the etiology of colon cancer. Conditional stabilization of this molecule in pro-T cells promotes thymocyte development without the requirement for pre-TCR signaling. We show here that activated β-catenin stalls the developmental transition from the double-positive (DP) to the single-positive (SP) thymocyte stage and predisposes DP thymocytes to transformation. β-Catenin–induced thymic lymphomas have a leukemic arrest at the early DP stage. Lymphomagenesis requires Rag activity, which peaks at this developmental stage, as well as additional secondary genetic events. A consistent secondary event is the transcriptional up-regulation of c-Myc, whose activity is required for transformation because its conditional ablation abrogates lymphomagenesis. In contrast, the expression of Notch receptors as well as targets is reduced in DP thymocytes with stabilized β-catenin and remains low in the lymphomas, indicating that Notch activation is not required or selected for in β-catenin–induced lymphomas. Thus, β-catenin activation may provide a mechanism for the induction of T-cell–acute lymphoblastic leukemia (T-ALL) that does not depend on Notch activation.
Comparing health system performance assessment and management approaches in the Netherlands and Ontario, Canada
Authors: Tawfik-Shukor Ali R , Klazinga Niek S , Arah Onyebuchi A 
Published: February 2007

Abstract

Background
Given the proliferation and the growing complexity of performance measurement initiatives in many health systems, the Netherlands and Ontario, Canada expressed interests in cross-national comparisons in an effort to promote knowledge transfer and best practise. To support this cross-national learning, a study was undertaken to compare health system performance approaches in The Netherlands with Ontario, Canada.

Methods
We explored the performance assessment framework and system of each constituency, the embeddedness of performance data in management and policy processes, and the interrelationships between the frameworks. Methods used included analysing governmental strategic planning and policy documents, literature and internet searches, comparative descriptive tables, and schematics. Data collection and analysis took place in Ontario and The Netherlands. A workshop to validate and discuss the findings was conducted in Toronto, adding important insights to the study.

Results
Both Ontario and The Netherlands conceive health system performance within supportive frameworks. However they differ in their assessment approaches. Ontario's Scorecard links performance measurement with strategy, aimed at health system integration. The Dutch Health Care Performance Report (Zorgbalans) does not explicitly link performance with strategy, and focuses on the technical quality of healthcare by measuring dimensions of quality, access, and cost against healthcare needs. A backbone 'five diamond' framework maps both frameworks and articulates the interrelations and overlap between their goals, themes, dimensions and indicators. The workshop yielded more contextual insights and further validated the comparative values of each constituency's performance assessment system.

Conclusion
To compare the health system performance approaches between The Netherlands and Ontario, Canada, several important conceptual and contextual issues must be addressed, before even attempting any future content comparisons and benchmarking. Such issues would lend relevant interpretational credibility to international comparative assessments of the two health systems.
Post-traumatic stress disorder and post-traumatic stress symptoms following critical illness in medical intensive care unit patients: assessing the magnitude of the problem
Authors: Jackson James C , Hart Robert P , Gordon Sharon M , Hopkins Ramona O , Girard Timothy D , Ely EWesley 
Published: February 2007

Abstract
Introduction
Post-traumatic stress disorder (PTSD) is a potentially serious psychiatric disorder that has traditionally been associated with traumatic stressors such as participation in combat, violent assault, and survival of natural disasters. Recently, investigators have reported that the experience of critical illness can also lead to PTSD, although details of the association between critical illness and PTSD remain unclear.

Methods
We conducted keyword searches of MEDLINE and Psych Info and investigations of secondary references for all articles pertaining to PTSD in medical intensive care unit (ICU) survivors.

Results
From 78 screened papers, 16 studies (representing 15 cohorts) and approximately 920 medical ICU patients met inclusion criteria. A total of 10 investigations used brief PTSD screening tools exclusively as opposed to more comprehensive diagnostic methods. Reported PTSD prevalence rates varied from 5% to 63%, with the three highest prevalence estimates occurring in studies with fewer than 30 patients. Loss to follow-up rates ranged from 10% to 70%, with average loss to follow-up rates exceeding 30%.

Conclusion
Exact PTSD prevalence rates cannot be determined due to methodological limitations such as selection bias, loss to follow-up, and the wide use of screening (as opposed to diagnostic) instruments. In general, the high prevalence rates reported in the literature are likely to be overestimates due to the limitations of the investigations conducted to date. Although PTSD may be a serious problem in some survivors of critical illness, data on the whole population are inconclusive. Because the magnitude of the problem posed by PTSD in survivors of critical illness is unknown, there remains a pressing need for larger and more methodologically rigorous investigations of PTSD in ICU survivors.
Meperidine and skin surface warming additively reduce the shivering threshold: a volunteer study
Authors: Kimberger Oliver , Ali Syed Z , Markstaller Monica , Zmoos Sandra , Lauber Rolf , Hunkeler Corinne , Kurz Andrea 
Published: February 2007

Abstract
Introduction
Mild therapeutic hypothermia has been shown to improve outcome for patients after cardiac arrest and may be beneficial for ischaemic stroke and myocardial ischaemia patients. However, in the awake patient, even a small decrease of core temperature provokes vigorous autonomic reactions–vasoconstriction and shivering–which both inhibit efficient core cooling. Meperidine and skin warming each linearly lower vasoconstriction and shivering thresholds. We tested whether a combination of skin warming and a medium dose of meperidine additively would reduce the shivering threshold to below 34°C without producing significant sedation or respiratory depression.

Methods
Eight healthy volunteers participated on four study days: (1) control, (2) skin warming (with forced air and warming mattress), (3) meperidine (target plasma level: 0.9 μg/ml), and (4) skin warming plus meperidine (target plasma level: 0.9 μg/ml). Volunteers were cooled with 4°C cold Ringer lactate infused over a central venous catheter (rate ≈ 2.4°C/hour core temperature drop). Shivering threshold was identified by an increase of oxygen consumption (+20% of baseline). Sedation was assessed with the Observer's Assessment of Alertness/Sedation scale.

Results
Control shivering threshold was 35.5°C ± 0.2°C. Skin warming reduced the shivering threshold to 34.9°C ± 0.5°C (p = 0.01). Meperidine reduced the shivering threshold to 34.2°C ± 0.3°C (p < 0.01). The combination of meperidine and skin warming reduced the shivering threshold to 33.8°C ± 0.2°C (p < 0.01). There were no synergistic or antagonistic effects of meperidine and skin warming (p = 0.59). Only very mild sedation occurred on meperidine days.

Conclusion
A combination of meperidine and skin surface warming reduced the shivering threshold to 33.8°C ± 0.2°C via an additive interaction and produced only very mild sedation and no respiratory toxicity.