bluuebunny/crossref_metadata_2025 huggingface dataset:
Inversion and uncertainty estimation of gravity data using simulated annealing: An application over Lake Vostok, East Antarctica
Authors: Roy Lopamudra , Sen Mrinal K. , Blankenship Donald D. , Stoffa Paul L. , Richter Thomas G.
Published: February 2005

Interpretation of gravity data warrants uncertainty estimation because of its inherent nonuniqueness. Although the uncertainties in model parameters cannot be completely reduced, they can aid in the meaningful interpretation of results. Here we have employed a simulated annealing (SA)–based technique in the inversion of gravity data to derive multilayered earth models consisting of two and three dimensional bodies. In our approach, we assume that the density contrast is known, and we solve for the coordinates or shapes of the causative bodies, resulting in a nonlinear inverse problem. We attempt to sample the model space extensively so as to estimate several equally likely models. We then use all the models sampled by SA to construct an approximate, marginal posterior probability density function (PPD) in model space and several orders of moments. The correlation matrix clearly shows the interdependence of different model parameters and the corresponding trade-offs. Such correlation plots are used to study the effect of a priori information in reducing the uncertainty in the solutions. We also investigate the use of derivative information to obtain better depth resolution and to reduce underlying uncertainties. We applied the technique on two synthetic data sets and an airborne-gravity data set collected over Lake Vostok, East Antarctica, for which a priori constraints were derived from available seismic and radar profiles. The inversion results produced depths of the lake in the survey area along with the thickness of sediments. The resulting uncertainties are interpreted in terms of the experimental geometry and data error.
Radiation pattern of a borehole radar antenna
Authors: Ellefsen Karl J. , Wright David L.
Published: February 2005

The finite-difference time-domain method was used to simulate radar waves that were generated by a transmitting antenna inside a borehole. The simulations were of four different models that included features such as a water-filled borehole and an antenna with resistive loading. For each model, radiation patterns for the far-field region were calculated. The radiation patterns show that the amplitude of the radar wave was strongly affected by its frequency, the water-filled borehole, the resistive loading of the antenna, and the external metal parts of the antenna (e.g., the cable head and the battery pack). For the models with a water-filled borehole, their normalized radiation patterns were practically identical to the normalized radiation pattern of a finite-length electric dipole when the wavelength in the formation was significantly greater than the total length of the radiating elements of the model antenna. The minimum wavelength at which this criterion was satisfied depended upon the features of the antenna, especially its external metal parts.
Magnetic-anomaly Fourier spectrum of a 3D Gaussian source
Authors: Tontini Fabio Caratori
Published: February 2005

I obtain a closed-form expression for the total-field magnetic anomaly generated by a 3D Gaussian magnetization distribution. The solution is evaluated by a novel contour integration in the complex-wavenumber domain. The spatial-domain solution is then computed by a numerical inverse Fourier transform. This calculated field can be used to interpret magnetic data because a 3D Gaussian function can represent a compact and smooth source. The method, moreover, allows for calculation of the Fourier components as a function of the distance between the depth of the source and the height of the observation level. The solution is thus useful for the inverse problem, spectral analysis, or data continuation.
Radiative transfer in layered media and its connection to the O'Doherty-Anstey formula
Authors: Haney Matthew M. , van Wijk Kasper , Snieder Roel
Published: February 2005

We examine radiative transfer theory, which accounts for the multiple scattering of waves in a layered medium composed of randomly placed thin beds excited by a 1D source. At its most basic level, radiative transfer predicts that the wavefield separates into a coherent, or wavelike, part and an incoherent, or diffusive, flow after a length scale known as a mean free path. The dynamic properties of the coherent and incoherent wavefield are linked. For 1D Rayleigh scatterers, or thin beds, we show that the exponential decay of the coherent wave predicted by radiative transfer corresponds to the decay predicted by the O'Doherty–Anstey formula. This equivalence reveals an underlying relationship between radiative transfer and mean field theory. Finite-difference simulations of the scalar wave equation with randomly placed thin beds demonstrate the diffusive behavior of the incoherent energy at late times.
Multiple attenuation in the image space
Authors: Sava Paul , Guitton Antoine
Published: February 2005

Multiples can be suppressed in the angle-domain image space after migration. For a given velocity model, primaries and multiples have different angle-domain moveout and, therefore, can be separated using techniques similar to the ones employed in the data space prior to migration. We use Radon transforms in the image space to discriminate between primaries and multiples and employ accurate functions describing angle-domain moveouts. Since every individual angle-domain common-image gather incorporates complex 3D propagation effects, our method has the advantage of working with 3D data and complicated geology. Therefore, our method offers an alternative to the more expensive surface-related multiple-elimination (SRME) approach operating in the data space. Radon transforms are cheap but not necessarily ideal for separating primaries and multiples, particularly at small angles where the moveout discrepancy between the two kinds of events are not large. Better techniques involving signal/noise separation using prediction-error filters can be employed as well, although such approaches fall outside the scope of this paper. We demonstrate, using synthetic and real data examples, the power of our method in discriminating between primaries and multiples after migration by wavefield extrapolation, followed by transformation to the angle domain.
Rough-sea deghosting of streamer seismic data using pressure gradient approximations
Authors: Amundsen Lasse , Røsten Tage , Robertsson Johan O. A. , Kragh Ed
Published: February 2005

A new method is presented for seismic deghosting of towed streamer data acquired in rough seas. The deghosting scheme combines pressure recordings along one or several cables with an estimate of the vertical pressure gradient (or the vertical component of the particle velocity). The estimation of the vertical pressure gradient requires continuous elevation measurements of the wave height directly above the receivers. The vertical pressure gradient estimate is obtained by spatially weighting the pressure field. Each spatial weight generally is the product of two weight functions. The first is a function of partial derivatives acting solely along the horizontal Cartesian coordinates. It can be implemented by finite-difference or Fourier derivative operations. The second is a function of the vertical Cartesian coordinate and accounts for the varying sea state. This weight can be changed from one receiver to the next, making the deghosting a local process. Integrated with the measured pressure field, the estimate of the vertical pressure gradient also enables other seismic processing opportunities beyond deghosting.
Launching GEOPHYSICS Letters
Authors: Robertsson Johan O. A.
Published: February 2005

Do you have a hot topic that will interest the geoscience community? Are you looking for a timely way to publish scientific advances in a prestigious journal?
This Issue of GEOPHYSICS
Authors: Schuster Gerard T.
Published: February 2005

In this article, the Editor of Geophysics provides an overview of all technical articles in this issue of the journal.
Circulating levels of tissue factor and proinflammatory cytokines in patients with primary antiphospholipid syndrome or leprosy related antiphospholipid antibodies
Authors: Forastiero R R , Martinuzzo M E , de Larrañaga G F
Published: February 2005

The antiphospholipid syndrome (APS) is characterized by the presence of antiphospholipid antibodies (aPL) in patients with thromboembolic complications. In APS, most aPL are autoantibodies to β2-glycoprotein I and prothrombin, which play a major role in the APS pathogenesis. Nevertheless, antibodies with the same antigen specificity are also found in aPL patients with leprosy, in whom thromboembolic complications are uncommon. The in vivo upregulation of the tissue factor (TF) pathway and the imbalance of cytokines have been proposed as potential mechanisms of thrombosis in the APS. We measured the circulating levels of TF, interleukin 6 (IL-6), IL-6 receptor (sIL-6R), tumor necrosis factor (TNF-a) and interferon g (IFN-g) in 83 patients with autoimmune aPL (42 with and 41 without clinical features of definite primary APS), 48 leprosy patients (33 with aPL) and 48 normal controls. There was a trend (P = 0.06) to higher median sTF in patients with autoimmune aPL (139 pg/mL) compared with leprosy patients (103.5 pg/mL) and controls (123 pg/mL). In addition, the frequency of raised sTF levels (.187 pg/mL) was significantly higher in the group with autoimmune aPL [22.9% (APS 21.4%, non-APS 24.4%)] but not in leprosy (10.4%) compared with controls (4.2%). Elevated levels of IL-6 and TNF-a and a trend to lower IFN-g were found in patients with definite APS. Leprosy patients with aPL, however, had increased TNF-a and IFN-g but normal IL-6 levels. Levels of sIL-6R did not differ between controls and either patients with autoimmune aPL or leprosy. The different cytokine profiles as well as differences in circulating levels of TF might contribute to the high thrombotic risk found in patients with autoimmune aPL but not in leprosy related aPL patients.
Cardiac magnetic resonance imaging abnormalities in systemic lupus erythematosus: a preliminary report
Authors: Singh J A , Woodard P K , Dávila-Román V G , Waggoner A D , Gutierrez F R , Zheng J , Eisen S A
Published: February 2005

The purpose of this prospective, pilot study was to determine whether differences in myocardial T2 relaxivity can be identified among active systemic lupus erythematosus (SLE) patients with clinically suspected SLE myocarditis, other active SLE patients, inactive SLE patients and age and gender matched controls. Eleven consecutive female patients (six with active SLE and five with inactive SLE), and five age, gender and race matched healthy controls underwent imaging with echocardiography and cardiac magnetic resonance imaging (MRI). Echocardiographic measurements included left ventricular end diastolic (LVEDV) and end systolic volumes (LVESV), and mass (LVM) (all indexed to body mass); ejection fraction and cardiac output. The cardiac MRI measurement was the T2 relaxation time (an index of soft tissue signal, with higher levels suggestive of increased tissue water content). Patients with active SLE had significantly higher LVEDVand LVM than inactive SLE patients and healthy controls, and significantly larger LVESV than healthy controls. Myocardial T2 relaxation times were significantly higher in patients with active SLE compared to those with inactive SLE and to healthy controls, and remained higher even after excluding the two active SLE patients who had clinical myocarditis. The four active SLE patients who underwent repeat cardiac imaging studies after clinical improvement showed normalization of these myocardial abnormalities. The conclusion was that active SLE patients demonstrate abnormalities in myocardial structure manifested by high myocardial T2 relaxation times that normalized after clinical improvement in disease activity. These findings suggest that T2 relaxation values are a sensitive indicator of myocardial disease in patients with SLE and that myocardial T2 relaxation abnormality frequently occur in patients with active SLE, even in the absence of myocardial involvement by clinical criteria.
Impact of external quality assessment on antinuclear antibody detection performance
Authors: Pham B-N , Albarede S , Guyard A , Burg E , Maisonneuve P
Published: February 2005

Our objective was to evaluate performance of the clinical laboratories for the detection of antinuclear antibodies (ANA) by using indirect immunofluorescence method (IIF), in France. A national external quality assessment (EQA) on ANA detection was organized by the French health products safety agency once a year since 1998. Between 606 to 687 laboratories together with six university reference laboratories experienced in performing tests in autoimmunity participated in the six-year consecutive survey. Each laboratory had to answer to methodological procedures and give coded responses. Variability in IIF methodological procedure was observed. Use of inappropriate microscope magnifications for reading slides or nonconventional cutoff dilution of serum were pointed out to concerned laboratories. Concerning ANA measurement, the rate of good responses ranged from 92.7% to 99.5% of the laboratories when the samples contained ANA. A wide dispersion of ANA titers obtained on a same sample was repeatly observed every year. Misinterpretation of particular fluorescence pattern was noticed. On ANA negative sample, the rate of good responses was 94.3%. In conclusion, ANA detection in routine practice is far from being standardized. However, EQA may have an impact on ANA detection performance when it is conducted on several consecutive year surveys, by providing advice for participating laboratories to limit inter laboratory variations related to methodological procedures.
Anti-B cell therapy (Rituximab) in the treatment of autoimmune diseases
Authors: Chambers S A , Isenberg D
Published: February 2005

The use of B cell depletion as a mode of treatment for non-Hodgkin’s lymphoma was first utilized in 1997 when Rituximab, a chimeric human-mouse monoclonal antibody which has a high affinity to the CD20 antigen expressed on B cells, became available. Over 500 000 lymphoma patients have been treated worldwide with this drug and it has a good safety record. The notion that B cells might be critical to the development of rheumatoid arthritis led to the extension of the use of B cell depletion to this condition and a recent double blind controlled trial has shown very encouraging results. In addition, B cell depletion either using Rituximab alone, or in combination with cyclophosphamide and corticosteroids has also been reported to have been of great benefit in some patients with severe systemic lupus erythematosus albeit in open label studies. This review considers the mechanism of action of the drug, the clinical trials that have been reported, and tries to place its current use in patients with autoimmune rheumatic disease in context.
Optimal two-stage randomized phase II clinical trials
Authors: Logan Brent R
Published: February 2005

Randomized phase II clinical trials can be an efficient means of evaluating several potential new treatments prior to a comparative phase III clinical trial. However, selection designs do not allow for an assessment of minimal efficacy, nor do they allow early closing of a study arm for lack of efficacy, and so are only appropriate when all arms have met minimal efficacy requirements. Classic two-stage hypothesis testing based designs such as a Simon two-stage optimal design can satisfy these requirements, when used in parallel for the multiple treatment arms. However, these can be inefficient and impractical in terms of the maximum planned sample size required for such a study. This article proposes a two-stage randomized phase II clinical trial, where the sample size is adaptive at the second stage to the number of treatment arms passing through the first stage. The study design relies on optimality criteria, which are analogous to those used by Simon for single-arm studies. The proposed design maintains similar operating characteristics to a strategy of using multiple single-arm studies, in most situations of primary interest. Furthermore, it generally has smaller actual sample size when most of the treatments are effective than using multiple single-arm studies, leading to substantial efficiencies in terms of maximum planned sample size.
Data monitoring in randomized controlled trials: surveys of recent practice and policies
Authors: Clemens Felicity , Elbourne Diana , Darbyshire Janet , Pocock Stuart ,   DAMOCLES Group
Published: February 2005

Background Data Monitoring Committees (DMCs) are increasingly involved in the conduct of randomized controlled trials, but there is little documented evidence of what they do. Three interlinked surveys were carried out as part of the DAMOCLES project to explore recent and current DMC practice and policy.

Methods 1) A questionnaire about DMC practice was sent to sample of 45 authors of trials published in selected journals in 2000. The sample was stratified by centre (single/multiple), disease area, and presence of DMC. 2) A sample of investigators in trials ongoing in the United Kingdom in 2001–02 was also sent a questionnaire about DMC practice. The sample was drawn from trials funded by the Medical Research Council, the United Kingdom Department of Health's Health Technology Assessment Programme, and a local and a multicentre research ethics committee. The sample was additionally stratified by funder (public/industry), centre (single/ multiple), and disease area. 3) A sample of major organisations involved in randomised controlled trials was sent a questionnaire about DMC policies.

Results Information about DMC practice from the first survey was obtained from 31 trials (69%), of which four had a DMC. Information about DMC practice from the second survey was obtained about 36 trials (90%), of which 20 had a DMC. Information about DMC policy from the third survey was obtained from 25 out of 25 organisations. There was general agreement about the sorts of trials particularly needing independent DMCs, but there were few uniform approaches to their modes of functioning, and few of the organisations surveyed had developed formal policies. Conclusions The roles of existing DMCs and policies governing DMC functioning vary widely across trials and organisations that sponsor or oversee trials, both within the UK and internationally. These findings reinforce previous calls for development of such policies across a wider range of organisations, better means to monitor their implementation within trials, and wider use of structured “charters”, which set out DMC modus operandi in advance.
Evaluating the quality of informed consent
Authors: Sugarman Jeremy , Lavori Philip W. , Boeger Maryann , Cain Carole , Edson Robert , Morrison Vicki , Yeh Shing Shing
Published: February 2005

Context Although informed consent is a critical means of protecting the rights and interests of participants in clinical research, effective and efficient means of evaluating the quality of consent are needed. Having such means will be important to monitoring consent and testing potential improvements in the consent process. Objective To develop and test a practical and general means of evaluating the quality of informed consent for clinical research.

Methods We developed and tested the Brief Informed Consent Evaluation Protocol (BICEP), a short telephone-based assessment of informed consent. As soon as patient-participants completed the informed consent process for a participating VA Cooperative Studies Program clinical trial they called an interviewer who administered the BICEP.

Results 632 participants completed BICEP, representing eight ongoing studies from 14 VA and one non-VA medical centers across the country. Site coordinators reported little to no difficulty implementing BICEP. The average duration of BICEP was 8.8 minutes (SD 3.6). Overall, patient-participants evaluated the informed consent process positively. A reliable coding system was then developed to analyze the verbatim responses of the final 191 participants. An Informed Consent Aggregate Score (ICAS) had a mean score of 8.23 (SD 1.17) with a range of 0–10, with 10 a perfect score; and a Therapeutic Misconception Aggregate Score (TMAS) had a mean of 1.62 (SD 0.93) with a range of 0–5, with 5 a perfect score.

Conclusions The BICEP is an efficient means of evaluating informed consent that is acceptable to research participants and research personnel. While participants tend to be satisfied with the informed consent process, the BICEP indicates there is room for improvement in the informed consent process for research.
Is the future for clinical trials internet-based? A cluster randomized clinical trial
Authors: Litchfield Jennifer , Freeman Jenny , Schou Henrik , Elsley Mark , Fuller Robert , Chubb Barrie
Published: February 2005

Objective To compare the efficiency and ease of use of internet data capture compared with conventional paper based data recording in the conduct of a clinical trial.

Design Multicentre, cluster randomized clinical trial.

Setting General practice in the UK.

Main outcome measures Timings for study landmarks, queries, data entry and monitoring time; Investigator Questionnaire Results.

Results The internet-derived database was ready for release 33 days after the last patient visit compared with 48 days for the paper-derived database, despite much higher numbers of patients in the internet group. The mean times from visit to data entry were 10.2 (SD 18.9) days and 95.4 (SD 44.6) days respectively (P, 0.01). The mean times from a visit to a query being resolved were 121.4 (SD 58.3) days and 182.1 (SD 58.9) days respectively (P, 0.01). The post-study responses from investigators were positive. Seventy-one percent of centressaid they would prefer to use the internet rather than paper CRFs for future studies.

Conclusions There were efficiency gains seen with the use of an internet-based system when compared with a paper-based system in terms data entry, query resolution and the time to the release of the data base. The investigators'response to the internet system was generally favourable although on average investigators reported increased time spent on the study. Further efficiency might be gained with improved programming, increased investigator familiarity with the internet system, and with newly adapted working practices for sponsors' monitors and database personnel.
Web-based distributed data management in the Childhood Asthma Research and Education (CARE) Network
Authors: Schmidt James R , Vignati Aimee J , Pogash Rosanne M , Simmons Vanessa A , Evans Richard L
Published: February 2005

A well-designed distributed data management application provides an efficient, effective process to collect quality data in multicenter clinical trials. This paper describes the web-based clinical center data management application that was developed by the Data Coordinating Center of the Childhood Asthma Research and Education (CARE) Network. A series of modules was designed to allow the clinical staff at the remote clinical centers to enter clinical trial data, correct entry errors, respond to queries from the Data Coordinating Center, and submit data corrections for previously entered data to ultimately provide a clean and accurate dataset for analysis.
Development of psychotherapeutic training in learning disability
Authors: Cooke Leila B. , Hargovan Heena
Published: February 2005

There has been an increasing awareness of the usefulness of psychotherapy as a treatment modality for people with learning disabilities and mental health problems over recent years. However, the difficulties involved in providing appropriate training and supervision in this field has resulted in a patchy and erratic development of service provision nationally (Royal College of Psychiatrists, 2004). A review by Hollins and Sinason (2000) of all the available published evidence found that nationally there was inadequate availability of psychological treatments for people with learning disabilities, that there had been few outcome studies published and most of the literature consisted of single case studies. They recommended that ongoing clinical audit, using standard outcome measures, should be part of learning disability psychotherapy service protocols, and that psychotherapy training and supervision should be made available to health and social care practitioners in the learning disability field.
Idea Habitats: How the Prevalence of Environmental Cues Influences the Success of Ideas
Authors: Berger Jonah A. , Heath Chip
Published: February 2005

We investigate 1 factor that influences the success of ideas or cultural representations by proposing that they have a habitat, that is, a set of environmental cues that encourages people to recall and transmit them. We test 2 hypotheses: (a) fluctuation: the success of an idea will vary over time with fluctuations in its habitat, and (b) competition: ideas with more prevalent habitats will be more successful. Four studies use subject ratings and data from newspapers to provide correlational support for our 2 hypotheses, with a negative factoid, positive rumor, catchphrases, and variants of a proverb. Three additional experimental studies manipulate the topic of actual conversations and find empirical support for our theory, with catchphrases, proverbs, and slang. The discussion examines how habitat prevalence applies to a more extensive class of ideas and suggests how habitats may influence the process by which ideas evolve.
Consequences of the Serial Nature of Linguistic Input for Sentenial Complexity
Authors: Grodner Daniel , Gibson Edward
Published: February 2005

All other things being equal the parser favors attaching an ambiguous modifier to the most recent possible site. A plausible explanation is that locality preferences such as this arise in the service of minimizing memory costs—more distant sentential material is more difficult to reactivate than more recent material. Note that processing any sentence requires linking each new lexical item with material in the current parse. This often involves the construction of long‐distance dependencies. Under a resource‐limited view of language processing, lengthy integrations should induce difficulty even in unambiguous sentences. To date there has been little direct quantitative evidence in support of this perspective. This article presents 2 self‐paced reading studies, which explore the hypothesis that dependency distance is a fundamental determinant of reading complexity in unambiguous constructions in English. The evidence suggests that the difficulty associated with integrating a new input item is heavily determined by the amount of lexical material intervening between the input item and the site of its target dependents. The patterns observed here are not straightforwardly accounted for within purely experience‐based models of complexity. Instead, this work supports the role of a memory bottleneck in language comprehension. This constraint arises because hierarchical linguistic relations must be recovered from a linear input stream.
Processing Coordinated Structures: Incrementality and Connectedness
Authors: Sturt Patrick , Lombardo Vincenzo
Published: February 2005

We recorded participants' eye movements while they read sentences containing verb‐phrase coordination. Results showed evidence of immediate processing disruption when a reflexive pronoun embedded in the conjoined verb phrase mismatched the sentence subject. We argue that this result is incompatible with models of human parsing that employ only bottom‐up parsing procedures, even when flexible constituency is employed. Models need to incorporate a mechanism similar to the adjoining operation in Tree‐Adjoining Grammar, in which one structure is inserted into another.
Reliability sensitivity of automobile components with arbitrary distribution parameters
Authors: Zhang Y M , He X D , Liu Q L , Wen B C , Zheng J X
Published: February 2005

Techniques from the perturbation method, the Edgeworth series, the reliability-based design theory, and the sensitivity analysis approach are employed to present a practical and efficient method for the reliability sensitivity of automobile components with arbitrary distribution parameters. On the condition of first four moments of original random variables known, the reliability sensitivity theory and case studies are researched. The respective program can be used to obtain the reliability sensitivity of automobile components with arbitrary distribution parameters accurately and quickly.
Experimental investigation on the steady-state performance and piston stroke length control of a variable displacement wobble plate compressor
Authors: Tian Changqing , Dou Chunpeng , Li Xianting , Liao Yunfei
Published: February 2005

The aim of this paper is to find out the steady-state performance and piston-stroke-length control behaviour of a variable displacement wobble-plate compressor for an automotive air-conditioning system by experimental investigation. First, a new method and device to measure the piston stroke length of the variable displacement compressor has been developed, with which the test bench for the variable displacement compressor has been set up. Second, the steady-state performance of the variable displacement compressor, such as the relative volumetric efficiency and the relative isentropic efficiency at partial piston stroke length, has been obtained. The influence of the work condition and compressor rotary speed on the relative volumetric efficiency can be neglected according to the test data. Finally, the critical wobble-plate case pressure is proposed in this paper to judge whether the piston stroke length will change or not. The critical wobble-plate case pressure when the piston stroke length decreases is greater than that when the piston stroke length increases, which is less influenced by the piston stroke length itself from the test data. The higher the compressor discharge pressure or rotary speed, the greater the critical wobble-plate case pressure. The piston stroke length can be adjusted automatically along with the air-conditioning load when the compressor rotary speed or air conditioning load changes.
Vehicle-pedestrian collisions: Validated models for pedestrian impact and projection
Authors: Wood D P , Simms C K , Walsh D G
Published: February 2005

The most important factor in pedestrian injuries from vehicle collisions is the impact velocity. In cases where the impact configuration can be ascertained, the most common method now used to determine vehicle speed involves the pedestrian projection distance. The more traditional method of using tyre brake marks is losing applicability as ABS braking systems become more common. The two most common impact configurations are wrap projection and forward projection, these being determined by the vehicle/pedestrian geometry and the initial conditions of the impact. In this paper, two models are presented for pedestrian forward and wrap projection impacts. These models are predicated on separating the total projection distance into the individual projection distances occurring during three principal phases of the collision. The models are novel as they use a rigid single-segment body representation of the pedestrian, include explicit modelling of the impact phase, and also allow for uncertainty in the input parameters. Published data are used to provide distributions for the input variables such as pedestrian and vehicle masses, etc. The model predictions of impact speed from overall projection distance are validated by comparison with real-world accident data.
Stereoselective Tandem Aldol-Tishchenko Reaction with Acylsilanes
Authors: Honda Mitsunori , Iwamoto Ryota , Nogami Yoshie , Segi Masahito
Published: February 2005

The treatment of acetyltrimethylsilane with LDA, followed by reaction of the resulting enolate with the excess amount of aldehydes gave the corresponding 1,3-diol derivatives in moderate yields with perfect diastereoselectivity as a single regioisomer via tandem aldol-Tishchenko reaction, whereas the reaction with α-branched aldehydes under similar conditions gives a mixture of two regioisomers. The reaction using benzyl trimethylsilyl ketone afforded the corresponding 1,3-diol monoesters having three contiguous stereogenic centers with perfect levels of stereochemical control in one-pot.
A Novel Modification for Silicalite-1 with High Stability and Selectivity in Vapor Phase Beckmann Rearrangement of Cyclohexanone Oxime
Authors: Tao Weichuan , Mao Dongsen , Xia Jianchao , Chen Qingling , Hu Ying
Published: February 2005

This paper presents a novel modification of highly siliceous MFI zeolites with hydrofluoric acid treatment: Silicalite-1 undergone such treatment exhibited remarkable improvements in stability and selectivity for Beckmann rearrangement of cyclohexanone oxime, which are even much better than those obtained by basic modification.
New Method for Preparation of Isolable N-tert-Alkoxyarylaminyl Radicals
Authors: Miura Yozo , Muranaka Yoshikazu
Published: February 2005

Stable N-tert-alkoxy-2,4-diphenyl-6-tert-butylphenylaminyl radicals were prepared by heating 2,4-diphenyl-6-tert-butylphenylnitrosobenzenes and azo compounds in refluxing benzene and isolated as radical crystals. Their structures were confirmed by the elemental analyses, ESR, and X-ray crystallography.
The First Isolation of 1,3-Diaza-2-sila-4-cyclopentene Radical Cation Salt: The X-ray Structure and Electronic Properties
Authors: Ishida Shintaro , Nishinaga Tohru , Komatsu Koichi
Published: February 2005

The first TPFPB salt of 1,3-diaza-2-sila-4-cyclopentene (DASCP) radical cation was isolated as an orange crystalline solid by one-electron oxidation of the neutral DASCP with Ag(I) ion. The X-ray structural analysis and theoretical studies showed that the silicon atom plays an important role in stabilization of this cationic species.
Synthesis of Na-A Zeolite from 10 Å Halloysite and a new Crystallization Kinetic Model for the Transformation of Na-A into HS Zeolite
Authors: Novembre Daniela , Di Sabatino Bruno , Gimeno Domingo
Published: February 2005

The present work deals with the synthesis of Na-A zeolite using 10 Å halloysite (collected near Grosseto, Italy) as the starting material, instead of the more expensive chemicals currently used in industry (Na aluminates and Na silicates). The process of synthesizing Na-A zeolite from 10 Å halloysite is rather simple as the reaction of halloysite with alkali occurs very readily and is achieved without prior thermal activation at high temperature. The optimal conditions of crystallization of Na-A zeolite from 10 Å halloysite are reached at 80°C. At lower temperatures, transformation of halloysite into an amorphous material requires more time, and the field within which Na-A zeolite exists overlaps that of 7 Å halloysite, G and HS zeolites. The products of synthesis at 80°C were characterized by X-ray diffraction, scanning electron microscopy, inductively coupled plasma optical emission spectrometry and infrared spectroscopy. We also propose a model to study the reaction kinetics of zeolite (Na-A and HS) nucleation and growth by real-time X-ray powder diffraction data.
A Smectite Dehydration Model in a Shallow Sedimentary Basin: Model Development
Authors: Liu Chen-Wuing , Lin Wen-Sheng
Published: February 2005

Traditionally, land subsidence resulting from groundwater over-pumping has often been described by the theory of consolidation. The mechanism of land subsidence due to the dehydration of clay minerals has not been well addressed. Therefore, this study develops a smectite dehydration model to describe the effect of the release of water from the smectite interlayer upon land subsidence. Using a thermodynamic solid-solution model and laboratory studies of clay-water systems, a complete description of the dehydration relationships among the swelling pressure, basal spacing and mw/mc in a Na-smectite water system at 25°C under variable pressure conditions was derived. Accordingly, the evaluation model of the ‘hydration state of smectite’, and the ‘solid-solution model of smectite dehydration’ were formulated rigorously. These two models were applied to quantify the effects of smectite dehydration on the accumulated land subsidence in the Yun Lin offshore industrial infrastructure complex and in the Tai-Shi area. The result reveals that smectite dehydration is of importance in assessing and predicting land subsidence in a shallow sedimentary basin.
Law's Dream of a Common Knowledge
Authors: Ratel Guillaume
Published: February 2005

Law's Dream of. Common Knowledge Mariana Valverde (Princeton: Princeton University Press, 2003)
Factors Affecting Regional Variation in Growth of Channel Catfish
Authors: Durham Bart W. , Pope Kevin L. , Wilde Gene R.
Published: February 2005

We related the length at age of channel catfish Ictalurus punctatus, an indirect measure of growth, to three climatic and five morphoedaphic variables in 144 Texas reservoirs. Growth of channel catfish ages 3 through 6 was negatively related to longitude, a factor that explained as much as 34% of the variation in length at age. Channel catfish length at age was not significantly related to latitude, conductivity, morphoedaphic index, mean depth, and maximum depth in all age-classes. Among age-7 channel catfish, length at age was positively related to reservoir area, which explained 35% of the variation in growth. A quadratic model for growing-season length explained 7–17% of the variation in length at age in all age-classes. Overall, length at age for channel catfish was greatest in reservoirs with intermediate growing seasons (approximately 270 d in length) and was lower when the growing-season length was either longer or shorter. Our results provide the first evidence that the length of growing season on a statewide or regional scale may affect the growth of channel catfish.
Morphology and Aging Precision of Statoliths from Larvae of Columbia River Basin Lampreys
Authors: Meeuwig Michael H. , Bayer Jennifer M.
Published: February 2005

The general morphology and precision associated with age determination of statoliths from larval Pacific lampreys Lampetra tridentata and western brook lampreys L. richardsoni found within the Columbia River basin were examined. Significant positive correlations were observed between the size of left and right statoliths from individuals. Principal components analysis indicated an allometric relationship between lamprey length and statolith size as well as a potential species grouping based on these measurements. Discriminant analysis was able to correctly classify more than 94% of Pacific lampreys and 92% of western brook lampreys based on lamprey length and statolith size, and Pacific lamprey statoliths tended to be larger than western brook lamprey statoliths for lampreys of a given size. Reader bias in age estimates of statoliths was greater for older lampreys. Multiple independent age readings of both statoliths from individual lampreys indicated that the overall average percent error was 16.7% for Pacific lampreys and 33.0% for western brook lampreys. Within-individual average percent error ranged from 5.1% to 20.1% among species and readers. Within-reader average percent error ranged from 6.4% to 17.8% among species and readers. The average percent error observed in this study was greater than that observed in studies of other species of lampreys; however, statoliths that were ambiguous or difficult to read were not excluded from this study. In general, the modal separation of age-groups observed in length-frequency distributions for lampreys is poor, as seen in this study; therefore, statolith-based ages may verify or provide better estimates of population age structure. These data demonstrate that estimates of precision are necessary before management actions founded on statolith-based age structure determination are implemented.
Intrapopulation Variation in Egg Lipid and Fatty Acid Composition and Embryo Viability in a Naturally Spawning Walleye Population from an Inland Reservoir
Authors: Czesny Sergiusz , Rinchard Jacques , Dabrowski Konrad
Published: February 2005

The objective of the study was to evaluate the variation in embryo viability within a population of walleye Sander vitreus from an inland reservoir throughout the spawning season. Egg size, egg lipid content, and fatty acid composition were used as criteria to evaluate egg quality. Additionally, we sought to verify whether any particular size-class of females produces superior-quality eggs or whether the time of spawning (early, middle, or late) has an effect on egg quality. Seventy-seven ovulating walleye females (total length, 465–885 mm) were captured in Salt Fork Reservoir, Ohio, throughout the spawning season. Although egg diameter after water hardening varied among females (1.85–2.38 mm), egg size did not correlate with female length (P > 0.05). Average egg lipid content was 12.0 ± 1.3% (mean ± SD) of wet weight and was unrelated to egg diameter (P > 0.05). Neutral and phospholipid classes in eggs comprised 77.5 ± 4.7% and 22.5 ± 4.7% of total lipids, respectively. Egg diameter was not significantly related to any of the specific fatty acids from neutral or phospholipid fractions (P > 0.05). Moreover, egg fatty acid compositions from both neutral lipids and phospholipids did not change during the spawning season. High survival of embryos (90.0 ± 8.7%) from females across the observed size range was recorded regardless of the spawning period. We concluded that the quality of walleye eggs was consistently high and thus that the timing of gamete collection would not compromise hatchery programs.
Capture of Ovulating Female Sea Lampreys in Traps Baited with Spermiating Male Sea Lampreys
Authors: Johnson Nicholas S. , Siefkes Michael J. , Li Weiming
Published: February 2005

This study was conducted as an initial step in the development of a trapping technique for sexually mature female sea lampreys Petromyzon marinus. Recent research has demonstrated that spermiating male sea lampreys release a sex pheromone that attracts ovulating females. This discovery prompted us to hypothesize that traps baited with spermiating males would capture more ovulating females than empty traps or traps baited with nonspermiating males. We found that traps baited with spermiating males captured nearly 74% of the ovulating females released, whereas empty traps and traps baited with nonspermiating males did not capture any ovulating females. We conclude that pheromone-baited traps may complement current sea lamprey management through direct removal of ripe females from spawning grounds.
Recent Water Temperature Trends in the Lower Klamath River, California
Authors: Bartholow John M.
Published: February 2005

Elevated water temperatures have been implicated as a factor limiting the recovery of anadromous salmonids in the Klamath River basin. This article reviews evidence of a multidecade trend of increasing temperatures in the lower main-stem Klamath River above the ocean and, based on model simulations, finds a high probability that water temperature has been increasing by approximately 0.5°C/decade (95% confidence interval (CI) = 0.42–0.60°C/decade) since the early 1960s. The season of high temperatures that are potentially stressful to salmonids has lengthened by about 1 month over the period studied, and the average length of main-stem river with cool summer temperatures has declined by about 8.2 km/decade. Water temperature trends seem unrelated to any change in main-stem water availability but are consistent with measured basinwide air temperature increases. Main-stem warming may be related to the cyclic Pacific Decadal Oscillation, but if this trend continues it might jeopardize the recovery of anadromous salmonids in the Klamath River basin.
Bluegill Recruitment, Growth, Population Size Structure, and Associated Factors in Minnesota Lakes
Authors: Tomcko Cynthia M. , Pierce Rodney B.
Published: February 2005

To better understand the differences among populations of bluegill Lepomis macrochirus, we analyzed the relationships between bluegill recruitment, growth, population size structure, and associated factors from approximately 2,600 Minnesota lakes. Potential explanatory variables for our models included bluegill year-class strength, growth, population size structure, the relative abundance and mean weight of predator species, physical and chemical characteristics of lakes, summer air temperature, and season. Bluegill year-class strength, growth, and population size structure were more strongly related to each other than to predator and lake characteristics, temperature, or season. Growth of age-6 bluegills was positively associated with population size structure and inversely related to year-class strength, suggesting density-dependent growth effects for adult bluegills. Growth of age-3 bluegills was inversely related to Secchi depth, so early growth and productivity may be linked. Bluegill population size structure was positively associated with length at age 5, as expected from the analysis of growth, and was inversely associated with mean year-class strength. Bluegill year-class strength was negatively associated with population size structure, length at ages 4 and 5, and lake area. Although predator variables were not included in one- or two-variable regression models, bluegill growth was positively related to the relative abundance of yellow perch Perca flavescens, walleye Sander vitreus (formerly Stizostedion vitreum), black bullhead Ameiurus melas, and brown bullhead A. nebulosus and negatively related to that of largemouth bass Micropterus salmoides and yellow bullhead A. natalis. The results suggest that management strategies for improving bluegill growth and population size structure should focus on bluegill recruitment and growth rather than on external environmental factors.
Functional Adult Literacy and Empowerment of Women: Impact of a Functional Literacy Program in Turkey
Authors: Kagitcibasi Cigdem , Goksen Fatos , Gulgoz Sami
Published: February 2005

This study addresses the impact of functional adult literacy on the empowerment of women in the absence of formal schooling. It examines whether the effects of functional literacy are exclusively content specific or whether there are gains going beyond the obvious benefits and extending to other spheres of everyday functioning, such as self‐concept, family relations, and social participation. The participants of a development intervention program implemented in Turkey, the Functional Adult Literacy Program, were studied for changes beyond specific gains in literacy. Study 1 took the form of a pretest/posttest design that examined women's self‐concept, family dynamics, social participation, and self‐efficacy before and after the intervention program. It involved a survey measuring the effects of a literacy program on women's self‐concept, social participation, and family dynamics and an experimental module assessing the impact of literacy on comprehension of television news. Study 2, conducted a year after participants had concluded the program, examined the stability of the gains and possible employment outcomes. Results indicate that the program contributed to women's social integration, positive self‐concept, and family cohesion. There were also cognitive gains. Sustained benefits were observed over time, though no change was found in possible employment outcomes.