bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reconstruction of an atmospheric tracer source using the principle of maximum entropy. I: Theory
Authors: Bocquet Marc 
Published: October 2005

AbstractOver recent years, tracing back sources of chemical species dispersed through the atmosphere has been of considerable importance, with an emphasis on increasing the precision of the source resolution. This need stems from many problems: being able to estimate the emissions of pollutants; spotting the source of radionuclides; evaluating diffuse gas fluxes; etc.We study the high‐resolution retrieval on a continental scale of the source of a passive atmospheric tracer, given a set of concentration measurements. In the first of this two‐part paper, we lay out and develop theoretical grounds for the reconstruction. Our approach is based on the principle of maximum entropy on the mean. It offers a general framework in which the information input prior to the inversion is used in a flexible and controlled way. The inversion is shown to be equivalent to the minimization of an optimal cost function, expressed in the dual space of observations. Examples of such cost functions are given for different priors of interest to the retrieval of an atmospheric tracer. In this respect, variational assimilation (4D‐Var), as well as projection techniques, are obtained as biproducts of the method. The framework is enlarged to incorporate noisy data in the inversion scheme. Part II of this paper is devoted to the application and testing of these methods. Copyright © 2005 Royal Meteorological Society
Reconstruction of an atmospheric tracer source using the principle of maximum entropy. II: Applications
Authors: Bocquet Marc 
Published: October 2005

AbstractA new method of performing the source inversion of a passive tracer at continental scale was proposed in Part I of this two‐part paper. The method made use of prior information, general or specific (depending on the situation), to perform a better reconstruction using only the prior information and the field measurements of the tracer. In this paper the method is tested on its first applications. It is used on several test examples, using the meteorological conditions of the European Joint Research Centre ETEX‐I campaign. The retrieval of a temporal profile of emission from a source whose location is known is studied before testing the method on a full reconstruction of the space–time profile of the source. Synthetic, but also real‐measurement, inversions are tested, thanks to the extension of the formalism to noisy data. Copyright © 2005 Royal Meteorological Society
Evolution of a subgrid deep convection parametrization in a limited‐area model with increasing resolution
Authors: Gerard L. , Geleyn J.‐F. 
Published: October 2005

AbstractThe adaptation of a convective parametrization to high resolution has been successfully performed, to a certain point, by refinements in the representation of the entrainment, detrainment and some other features of the original general‐circulation‐model oriented scheme. But, passing to resolutions below 10 km requires dispensing with some fundamental hypotheses, starting with quasi‐equilibrium and the assumption of negligible up‐ and downdraught mesh fractions. A prognostic scheme has been used for the draughts' vertical velocities and mesh fractions. The prognostic closure of the convective scheme has many benefits, but additional enhancements are required, starting with a coherent treatment of the cloud condensates and a more integrated combination of the different schemes producing condensation, cloud and precipitation. Copyright © 2005 Royal Meteorological Society
Experimental use of TRMM precipitation radar observations in 1D+4D−Var assimilation
Authors: Benedetti Angela , Lopez Philippe , Bauer Peter , Moreau Emmanuel 
Published: October 2005

AbstractThis paper presents a new application of the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) observations for indirect assimilation into the European Centre for Medium‐Range Weather Forecasts (ECMWF) model. The PR reflectivities are first processed using a one‐dimensional variational (1D‐Var) method to adjust model temperature and specific humidity. The retrieved Total Column Water Vapour (TCWV) is then assimilated into the operational four‐dimensional variational (4D‐Var) system. The applicability of the 1D+4D−Var approach to the radar observations is discussed in detail.Several case studies were run to assess the feasibility and the effectiveness of assimilating PR reflectivities with a 1D‐Var approach. Results show good behaviour of the 1D‐Var system in terms of convergence and stability. Its performance in terms of retrieved TCWV is comparable to that of other 1D‐Vars which make use of TRMM Microwave Imager (TMI) observations. When the 1D‐Var TCWV pseudo‐observations are input into the 4D‐Var system, a positive impact is shown in the analysis and the subsequent forecasts, both on moisture‐related fields and also on winds and surface pressure. The quality of the forecast is verified using track observations for the tropical cyclones. The track forecasts from the experiments which include 1D‐Var TCWV are generally closer to the observed track than a control run. Despite their much smaller spatial coverage than TMI observations, it is found that the PR data have a comparable impact, provided the satellite samples a meaningful portion of the storm, possibly its centre. This is possibly due to the fact that TCWV increments from PR and from TMI brightness temperature have similar magnitudes.These results show that active sensor data can provide indirect yet useful information on the moisture field and that this information can effectively be assimilated to improve the analysis and the forecast of tropical disturbances. Although this is a sub‐optimal use of PR observations, due to the underexploitation of the vertical information contained in the reflectivity profiles, it is still a step forward towards using active sensor data in preparation for future satellite missions which will deliver this type of data on a global scale and at higher temporal resolution. Copyright © 2005 Royal Meteorological Society
Can Coal Contribute to Sustainable Development?
Authors: Wicks Roger , Keay Malcolm 
Published: October 2005

Coal is not always seen as a route to sustainable development; renewable energy, energy efficiency and a move away from fossil fuels are what people usually have in mind. The paper argues that such a view is incomplete. One of the key development challenges facing the 21st century is to ensure wider access to clean energy. There are 1.6 billion people currently lacking electricity and the enormous benefits it brings in terms of poverty reduction and improved quality of life. Coal has been the route to electrification for millions in the developing world – China alone secured electricity access for over 700 million people between 1980 and 2000 in a system based 84 percent on coal. Clean technologies generally involve higher costs. Can the higher environmental expectations of the 21st century be met without denying or delaying access to electricity for millions in need? The paper identifies ways in which the cost penalty and other barriers to the introduction of clean coal-based technologies can be overcome. Higher efficiencies reduce both costs and emissions – the universal deployment of existing commercial best practice would produce savings equivalent to those from the Kyoto protocol. Emerging coal-based technologies enable cost-effective carbon dioxide emissions reductions. Co-firing of coal and renewables is often the most effective route to enabling resources such as biomass and solar power to be exploited. In the longer run, carbon sequestration offers huge potential for near zero emissions power at costs comparable with or lower than the alternatives. The conclusion is that no single fuel source provides the answer to sustainable development; a range of options is needed. Cleaner coal-based technologies must be one of those options: they can meet both immediate development goals and longer-term climate change imperatives.
Energy Access: Illusion or Reality for the Poor?
Authors: Fall Latsoucabe 
Published: October 2005

Electricity access is vital for alleviating poverty, and reversing the past and current negative economic and social trends in developing countries. However, despite efforts undertaken so far, the technological accomplishments and so-called breakthroughs, as well as global wealth, the population without electricity access in developing countries is still tremendous. In Sub-Saharan Africa, at least three-quarters of the population currently have no access to electricity; and over the past three decades, the number of people without access to electricity in this region has doubled. Moreover, if we applied the electricity connection rates of the past decade, one must wait until at least the end of this century, before achieving the electricity access objective set for the region. Some experts contend that electricity reform options experienced in Africa have not yet reached the expected beneficial effects, in terms of improvement of the electricity access rate for the poor, and that they were not designed to address the energy problems of the poor, but were explicitly aimed at achieving other objectives. It is thus well founded to raise the following questions: Is the WSSD objective of energy access realistic or utopian, particularly for Africa? Is the UN Millennium Development Goal of halving the number of African poor by 2015 a ‘white vow’? How can we reverse the past and current negative trends and move towards the achievement of ambitious yet realistic objectives of widespread energy access?
A 12‐month follow‐up study of self‐management training for people with chronic disease: Are changes maintained over time?
Authors: Barlow J. H. , Wright C. C. , Turner A. P. , Bancroft G. V. 
Published: October 2005

Objective. A previous study reported some improved outcomes at 4‐month follow‐up after attendance on a lay‐led, chronic disease self‐management course (CDSMC). The purpose of this study was to determine whether changes were maintained over time (i.e. at 12 months) and to describe participants' current use of self‐management techniques.Design. The study was a 12‐month follow‐up of a sample of 171 participants who attended a CDSMC in the UK.Method. Data were collected by self‐administered questionnaires mailed to participants 12 months after they commenced a CDSMC and via telephone interviews with a sub‐sample.Results. The sample had a mean age of 54 years, mean disease duration of 16 years, 73% were women, and chronic diseases included endometriosis, depression, diabetes, myalgic encephalomyelitis, osteoporosis and polio. The significant improvements in outcomes identified at 4 months (i.e. cognitive symptom management, self‐efficacy, communication with physician, fatigue, anxious and depressed moods and health distress) were sustained at 12 months. No significant changes between 4‐ and 12‐month assessments were found on any study variables. Interview data confirmed that participants continued to use some of the self‐management techniques learned on the course.Conclusion. Attendance on the CDSMC may lead to longer‐term changes in key outcomes such as self‐efficacy, use of some self‐management behaviours and some aspects of health status (e.g. fatigue, depressed mood).
Early treatment response as a predictor of ongoing weight loss in obesity treatment
Authors: Stotland S. C. , Larocque M. 
Published: October 2005

Objectives. This study examined early treatment response in obesity treatment, defined as early change in body mass index (BMI) and early change in eating behaviour, as a predictor of ongoing weight loss in obese patients.Methods.  We conducted a repeated measures analysis of eating behaviour, emotional factors (depression, stress, perfectionism) and BMI, over a 9 month period. Subjects were 344 females, aged 18–65 (mean = 41.8), with a BMI of at least 25 (mean BMI = 33.7), engaged in very‐low calorie (VLCD) or low‐calorie (LCD) diets.Results. Multi‐level modelling identified four significant predictors of ongoing weight loss (weight loss occurring between 5 weeks and 9 months after the start of treatment). These included: type of diet, early BMI change (start to 5 weeks), number of weigh‐ins and the early change in uncontrolled eating (start to 5 weeks). Estimates based on multi‐level modelling indicate that patients with strong versus weak early treatment responses would be expected to show large differences in ongoing weight loss.Conclusions. Early improvements in eating behaviour and weight appear to have additive effects in the prediction of ongoing weight change. Future research is required to identify the optimal rate of weight loss, whether there are critical periods for behaviour change, and factors which influence the likelihood of early behaviour change.
Goal disturbance predicts health‐related quality of life and depression 4 months after myocardial infarction
Authors: Boersma Sandra N. , Maes Stan , van Elderen Thérèse 
Published: October 2005

Objectives.The aim of this longitudinal study was to determine whether the event of a myocardial infarction (MI) would lead to a disturbance in important higher‐order goals, and whether goal disturbance could predict health‐related quality of life (HRQL) and depression 4 months later, in addition to baseline scores, demographic characteristics, presence of anginal complaints (AP) or chest pain, coping strategies and social support.Method.A total of 113 MI patients completed questionnaires shortly after hospitalization (T1) and 4 months later (T2), assessing (an impact of the event on) important higher‐order goals (T1), disease‐related coping strategies (T1), perceived adequacy of social support (T2), AP (T2), HRQL, and depression (T2). Two separate hierarchical regression analyses were performed with HRQL and depression at T2 as dependent variables.Results.The results suggest that the experience of an MI has an impact on the attainment of higher‐order goals. Goal disturbance is an independent predictor of both HRQL and depression after MI.Conclusion.A goal theory perspective can provide additional insights into HRQL outcomes after an MI.
Independent Validation of Candidate Breast Cancer Serum Biomarkers Identified by Mass Spectrometry
Authors: Li Jinong , Orlandi Rosaria , White C Nicole , Rosenzweig Jason , Zhao Jing , Seregni Ettore , Morelli Daniele , Yu Yinhua , Meng Xiao-Ying , Zhang Zhen , Davidson Nancy E , Fung Eric T , Chan Daniel W 
Published: October 2005

AbstractBackground: We previously selected a panel of 3 breast cancer biomarkers (BC1, BC2, and BC3) from serum samples collected at a single hospital based on their collective contribution to the optimal separation of breast cancer patients and noncancer controls by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The identities and general applicability of these markers, however, were unknown. In this study, we performed protein expression profiling on samples obtained from a second hospital, included a greater number of ductal carcinoma in situ (DCIS) cases, and performed purification and identification of the 2 confirmed markers.Methods: Using a case–control study design, we performed protein expression profiling on serum samples from the National Cancer Institute (Milan, Italy). The validation sample cohort consisted of 61 women with locally invasive breast cancer, 32 with DCIS, 37 with various benign breast diseases (including 13 atypical), and 46 age-matched apparently healthy women (age range, 44–68 years). Validated biomarkers were purified and identified with serial chromatography, 1-dimensional gel electrophoresis, in-gel ASP-N digestion, peptide mass fingerprinting, and tandem mass peptide sequencing.Results: The BC3 and BC2 expression patterns in this sample set were consistent with the first study sample set. BC3 and BC2 were identified to be complement component C3adesArg and a C-terminal–truncated form of C3adesArg, respectively.Conclusions: Evaluation of biomarkers in independent sample sets can help determine the broader utility of candidate markers, and protein identification permits understanding of their molecular basis. C3adesArg appears to lack specificity among patients with benign diseases, limiting its utility as a stand-alone tumor marker, but it may still be useful in a multimarker panel for early detection of breast cancer.
Estimating the Time of Last Cannabis Use from Plasma Δ9-Tetrahydrocannabinol and 11-nor-9-Carboxy-Δ9-Tetrahydrocannabinol Concentrations
Authors: Huestis Marilyn A , Barnes Allan , Smith Michael L 
Published: October 2005

Abstract
Background: Knowing the time cannabis was last used is important for determining impairment in accident investigations and clinical evaluations. Two models for predicting time of last cannabis use from single plasma cannabinoid concentrations—model I, using Δ9-tetrahydrocannabinol (THC), and model II, using the concentration ratio of 11-nor-9-carboxy-THC (THCCOOH) to THC—were developed and validated from controlled drug administration studies. Objectives of the current study were to extend the validation by use of a large number of plasma samples collected after administration of single and multiple doses of THC and to examine the effectiveness of the models at low plasma cannabinoid concentrations.
Methods: Thirty-eight cannabis users each smoked a 2.64% THC cigarette in the morning, and 30 also smoked a second cigarette in the afternoon. Blood samples (n = 717) were collected at intervals after smoking, and plasma THC and THCCOOH concentrations measured by gas chromatography–mass spectrometry. Predicted times of cannabis smoking, based on each model, were compared with actual smoking times.
Results: The most accurate approach applied a combination of models I and II. For all 717 plasma samples, 99% of predicted times of last use were within the 95% confidence interval, 0.9% were overestimated, and none were underestimated. For 289 plasma samples collected after multiple doses, 97% were correct with no underestimates. All time estimates were correct for 76 plasma samples with THC concentrations between 0.5 and 2 μg/L, a concentration range not previously examined.
Conclusions: This study extends the validation of the predictive models of time of last cannabis use to include multiple exposures and low THC concentrations. The models provide an objective and validated method for assessing the contribution of cannabis to accidents or clinical symptoms.
Lipoprotein-Associated Phospholipase A2 Activity Is a Marker of Small, Dense LDL Particles in Human Plasma
Authors: Gazi Irene , Lourida Evangelia S , Filippatos Theodosios , Tsimihodimos Vasilis , Elisaf Moses , Tselepis Alexandros D 
Published: October 2005

AbstractBackground: Recent clinical studies showed that lipoprotein-associated phospholipase A2 (Lp-PLA2) is a predictor for incident atherosclerotic disease. We have previously shown that among the LDL subfractions, Lp-PLA2 activity is preferentially associated with the atherogenic small, dense (sdLDL) particles in vitro. We investigated whether Lp-PLA2 could be a marker of sdLDL in human plasma.Methods: One hundred and seventy-six individuals participated in the study. LDL subclass analysis was performed by polyacrylamide gel electrophoresis. Lp-PLA2 activity and mass were determined in total plasma and in apolipoprotein B-depleted plasma (HDL-Lp-PLA2). Non–HDL-Lp-PLA2 activity and mass were calculated by subtracting the HDL-Lp-PLA2 from total plasma Lp-PLA2.Results: On the basis of the LDL subclass analysis, participants were categorized into phenotype A and non-A (total cholesterol mass of the sdLDL subfractions ≤0.155 and &gt;0.155 mmol/L, respectively). Unlike total plasma Lp-PLA2 mass, total plasma Lp-PLA2 activity and non–HDL-Lp-PLA2 activity and mass were significantly higher in persons with phenotype non-A compared with persons with phenotype A, whereas HDL-Lp-PLA2 activity and mass were lower in persons with phenotype non-A compared with phenotype A. Total plasma activity and non–HDL-Lp-PLA2 activity and mass, but not Lp-PLA2 mass, were correlated with sdLDL-cholesterol mass, proportion, and mean LDL particle size. In multiple regression analysis, total plasma and non–HDL-Lp-PLA2 activities were the second best predictors of the presence of sdLDL particles in human plasma after serum triglyceride concentrations. At serum triglyceride concentrations &gt;1.356 mmol/L, total plasma and non–HDL-Lp-PLA2 activity added significantly to the prediction of the presence of sdLDL in plasma.Conclusions: Lp-PLA2 activity, but not the enzyme mass, is a marker of sdLDL in human plasma.
Petroleum, Enhanced Oil Recovery
Authors: Borchardt John K. 
Published: October 2005

AbstractThe petroleum industry is becoming ever more dependent on increasing oil production from existing oil fields beyond the recovery in primary production and water flooding. Enhanced oil recovery employs various chemicals to increase the reservoir volume contracted by oil well injected fluids, ie, to increase the volumetric sweep efficiency, and thus increase production. Increases in the oil displacement efficiency can be brought about by a variety of mechanisms. The primary processes used to increase oil displacement efficiency are miscible gas flooding and steam flooding. Micellar polymer flooding and alkaline flooding may also be used. Miscible gas flooding most often employs carbon dioxide and/or hydrocarbon gases. Polymer flooding increases the volumetric sweep efficiency of waterflooding. The two most commonly used polymers used are partially hydrolyzed polyacrylamides and xanthan gum. Polymer injection followed byin situcross‐linking reduces the permeability of fractures and rock thief zones increasing volumetric sweep efficiency. Injection of surfactants and noncondensible gases to generate foamin situalso increases volumetric sweep efficiency.
Mass Spectrometry
Authors: de Hoffmann Edmond 
Published: October 2005

AbstractMass spectrometry is a technique which involves measurements of mass‐to‐charge ratios of the ions formed when a sample is ionized. The types of spectrometers are discussed, as are the ionization techniques and types of mass spectrometers used to solve analytical problems in biotechnology, environmental studies, polymer chemistry, forensics and inorganic applications. Detailed descriptions of instrumental components, the various ion paths, and data analyses are presented. Mass spectrometers for tandem mass spectrometry are discussed. The methodologies used to interface hplc and other separations systems to mass spectrometers are described.
Titanium Compounds, Organic
Authors: Putzig Donald E. , Moncarz Jillian R. 
Published: October 2005

AbstractOrganic titanium compounds are materials having a covalent bond between titanium and another atom that is also bonded to a carbon‐based group. Titanium tetrachloride, the basic raw material from which organic titanate compounds are made, is readily converted to tetraisopropyl titanate, TYZOR TPT, by the Nelles process. This ester can be converted by alkoxy exchange (transesterification) to a wide variety of tetraalkyl titanates, which in turn react with other ligands and chelating agents to give complexes having properties significantly different from the starting materials. This article covers all aspects of the organic titanium compound, from properties, reactions, and synthesis, to uses and health and safety factors.