bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel applications of highly sensitive liquid chromatography/mass spectrometry/mass spectrometry for the direct detection of ultra‐trace levels of contaminants in water
Authors: Seitz Wolfram , Schulz Wolfgang , Weber Walter H.
Published: June 2006

Recent advances in the sensitivity of liquid chromatography/mass spectrometry (LC/MS) instrument technology provide the basis for the direct detection, i.e. without sample pre‐concentration, of organic contaminants in water in the ng/L range. Novel applications for the analysis of atrazine and some of its desalkylated and hydroxylated degradation products, the pharmaceutical compounds diclofenac and carbamazepine, sulfonylurea herbicides, and iodinated X‐ray contrast media have been developed. For each analyte a specific tandem mass spectrometric (MS/MS) transition has been selected and the corresponding mass spectrometric parameters optimised. All analytes could be analysed within three specific analytical runs including different high‐performance liquid chromatography (HPLC) conditions. Detection limits were determined to be better than 10 ng/L for the direct analysis of the compounds in water except for X‐ray contrast media, for which detection limits were found to be up to one order of magnitude higher. The methods have been successfully utilised for the analysis of natural waters. Matrix effects frequently occurring in LC/MS have shown to be low to moderate in the case of X‐ray contrast media. This work demonstrates that for the analysis of a large number of water contaminants, the sample pre‐concentration step could possibly be omitted. Copyright © 2006 John Wiley & Sons, Ltd.
Quantification of tizanidine in human plasma by liquid chromatography coupled to tandem mass spectrometry
Authors: Nirogi Ramakrishna V. S. , Kandikere Vishwottam N. , Shukla Manoj , Mudigonda Koteshwara , Maurya Santosh
Published: June 2006

A simple, sensitive and rapid high‐performance liquid chromatography/positive ion electrospray tandem mass spectrometry (MS/MS) method was developed and validated for the assay of tizanidine in human plasma. Following liquid‐liquid extraction, the analytes were separated using an isocratic mobile phase on a reversed‐phase column and analyzed by MS/MS in the selected reaction monitoring mode. The assay exhibited a linear dynamic range of 50–5000 pg/mL for tizanidine in human plasma. The lower limit of quantification was 50 pg/mL with a relative standard deviation of less than 13%. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. A run time of 2.5 min for each sample made it possible to analyze more than 300 human plasma samples per day. The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetic, bioavailability or bioequivalence studies. Copyright © 2006 John Wiley & Sons, Ltd.
A multivariate test for population bioequivalence
Authors: Chervoneva Inna , Hyslop Terry , Hauck Walter W.
Published: June 2006

In this article, we propose a multivariate generalization of the criteria for testing univariate population bioequivalence. Recently, a number of approaches for testing multivariate equivalence have appeared in the literature. Most of them consider a multivariate equivalence region, which implies simultaneous comparison of means in each dimension. In contrast, our proposal combines a comparison of means and a comparison of variances into a single aggregate criterion, using the trace of the covariance matrix as a scalar measure of the total variability. We use a confidence interval approach to multivariate population bioequivalence testing, similar to the univariate case. Two versions of the modified large‐sample confidence interval for the linearized multivariate criterion are constructed. In a simulation study, we evaluate the empirical coverage of these confidence intervals and rejection rates of the corresponding tests in finite samples. The proposed methodology is illustrated with an example of testing equivalence of the spray pattern of nasal sprays. Copyright © 2006 John Wiley & Sons, Ltd.
Functional regression analysis using anFtest for longitudinal data with large numbers of repeated measures
Authors: Yang Xiaowei , Shen Qing , Xu Hongquan , Shoptaw Steven
Published: June 2006

Longitudinal data sets from certain fields of biomedical research often consist of several variables repeatedly measured on each subject yielding a large number of observations. This characteristic complicates the use of traditional longitudinal modelling strategies, which were primarily developed for studies with a relatively small number of repeated measures per subject. An innovative way to model such ‘wide’ data is to apply functional regression analysis, an emerging statistical approach in which observations of the same subject are viewed as a sample from a functional space. Shen and Faraway introduced anFtest for linear models with functional responses. This paper illustrates how to apply thisFtest and functional regression analysis to the setting of longitudinal data. A smoking cessation study for methadone‐maintained tobacco smokers is analysed for demonstration. In estimating the treatment effects, the functional regression analysis provides meaningful clinical interpretations, and the functionalFtest provides consistent results supported by a mixed‐effects linear regression model. A simulation study is also conducted under the condition of the smoking data to investigate the statistical power for theFtest, Wilks' likelihood ratio test, and the linear mixed‐effects model using AIC. Copyright © 2006 John Wiley & Sons, Ltd.
Improving point predictions of random effects for subjects at high risk
Authors: Lyles Robert H. , Manatunga Amita K. , Moore Reneé H. , DuBois Bowman F. , Cook Curtiss B.
Published: June 2006

The prediction of random effects corresponding to subject‐specific characteristics (e.g. means or rates of change) can be very useful in medical and epidemiologic research. At times, one may be most interested in obtaining accurate and/or precise predictions for subjects whose characteristic places them in a tail of the distribution. While the typical posterior mean predictor dominates others in terms of overall mean squared error of prediction (MSEP), its tendency to ‘overshrink’ has motivated research into alternatives emphasizing other criteria. Here, we specifically target MSEP within a certain region (e.g. above a known cut‐off for high risk or a specified percentile of the random effect distribution), and we consider minimizing this quantity with and without constraints on overall MSEP efficiency. We use the normal‐theory random intercept model to derive prediction methods with potential to yield markedly better performance for subjects in the specified region, given a well‐controlled and (if desired) modest concession of overall MSEP. Criteria geared toward classification as well as overall and regional prediction unbiasedness are also provided. We evaluate the proposed techniques and illustrate them using repeated measures data on fasting blood glucose from type 2 diabetes patients. A simulation study verifies that theoretical properties and relative performances of the proposed predictors are essentially maintained when calculating them in practice based on estimated mixed linear model parameters. Straightforward extensions to incorporate covariates and additional random effects are briefly outlined. Copyright © 2006 John Wiley & Sons, Ltd.
A practical approach to computing power for generalized linear models with nominal, count, or ordinal responses
Authors: Lyles Robert H. , Lin Hung‐Mo , Williamson John M.
Published: June 2006

Data analysts facing study design questions on a regular basis could derive substantial benefit from a straightforward and unified approach to power calculations for generalized linear models. Many current proposals for dealing with binary, ordinal, or count outcomes are conceptually or computationally demanding, limited in terms of accommodating covariates, and/or have not been extensively assessed for accuracy assuming moderate sample sizes. Here, we present a simple method for estimating conditional power that requires only standard software for fitting the desired generalized linear model for a non‐continuous outcome. The model is fit to an appropriate expanded data set using easily calculated weights that represent response probabilities given the assumed values of the parameters. The variance–covariance matrix resulting from this fit is then used in conjunction with an established non‐central chi square approximation to the distribution of the Wald statistic. Alternatively, the model can be re‐fit under the null hypothesis to approximate power based on the likelihood ratio statistic. We provide guidelines for constructing a representative expanded data set to allow close approximation of unconditional power based on the assumed joint distribution of the covariates. Relative to prior proposals, the approach proves particularly flexible for handling one or more continuous covariates without any need for discretizing. We illustrate the method for a variety of outcome types and covariate patterns, using simulations to demonstrate its accuracy for realistic sample sizes. Copyright © 2006 John Wiley & Sons, Ltd.
Klebetechnik für den schnellen und wirtschaftlichen Bau von Verbundbrücken
Authors: Dauner Hans‐Gerhard
Published: June 2006

Dieser Beitrag behandelt eine neue Technik für den Verbundbrückenbau. Dabei wird die Fahrbahnplatte aus untereinander verklebten Fertigteilen hergestellt. Der Verbund mit den Stahlträgern wird teilweise mittels einer Haftschicht auf Epoxydharzbasis erreicht. Damit ermöglichen auf der Klebetechnik beruhende Verfahren ein schnelles, wirtschaftlich vorteilhaftes und qualitativ hochwertiges Bauen von Verbundbrücken. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bestimmung der Wölbspannungen von doppeltsymmetrischen Kastenquerschnitten mit Diagrammen
Authors: Rubin Helmut
Published: June 2006

Bei torsionsbeanspruchten Stäben mit Kastenquerschnitten ist es in der Regel ausreichend, die Wölbkrafttorsion nur an den Stellen eines Einzeltorsionsmoments (Auflager‐ oder eingeprägtes Moment) zu untersuchen, und dies auch nur, wenn das Moment nicht an einem frei verwölbbaren Stabende angreift. Außerdem dürfen bei statisch unbestimmten Systemen die Auflagertorsionsmomente vereinfachend unter vollständiger Vernachlässigung der Wölbkrafttorsion bestimmt werden, weil deren Einfluß von der Stelle des Einzeltorsionsmoments aus rasch abklingt und somit die Torsionsdrehwinkel nur unwesentlich beeinflußt. Der vorliegende Beitrag erlaubt die Ermittlung der Wölbnormal‐ und ‐schubspannungen an den genannten Stellen mit Hilfe von Diagrammen oder alternativ mit Hilfe von Formeln, die nur von zwei Querschnittsparametern abhängen; dabei brauchen weder sekundäres Torsionsmoment noch Wölbmoment bestimmt zu werden. Die verwendete Theorie berücksichtigt die sekundären Schubverformungen, was bei geschlossenen Querschnitten stets erforderlich ist. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cell Wall Degrading Enzymes and Proteases Improve Starch Yields of Sorghum and Maize
Authors: Pérez‐Carrillo Esther , Serna‐Saldívar Sergio O.
Published: June 2006

The effects of a commercial cell‐wall‐degrading enzyme (CWDE) complex and/or commercial protease on yield and quality of starch extracted from white regular sorghum (RSOR), white waxy sorghum (WSOR) and yellow maize (YMZ) were determined. A bifactorial experiment with a level of confidence of P<0.05 was performed to study the effect of CWDE and/or protease addition to coarsely ground grains for 4 h after 20 h of regular SO2 steeping of whole kernels. Calcium oxide (CaO) or lactic acid were used to adjust the pH solution to 5.5 prior to grinding. YMZ yielded the highest amount of starch, whereas RSOR gave higher starch yield than WSOR. All enzyme treatments significantly (P<0.05) improved starch yields. Protease alone and CWDE plus protease treatments were the most effective treatments in terms of starch yields. These enzyme treatments allowed the recovery of more than 90% of the starch. The two types of sorghum starches contained higher amounts of residual protein and ash when compared with maize starch. The various enzymes treatments did not affect starch composition or Visco Analyser properties of each type of kernel. As expected, the WSOR starch had lower pasting temperature and retrogradation when compared with the regular starches.
From Starch to Starch Microspheres: Factors Controlling the Microspheres Quality
Authors: Elfstrand Lidia , Eliasson Ann‐Charlotte , Jönsson Monica , Reslow Mats , Wahlgren Marie
Published: June 2006

Starch microparticle is a dosage form suitable for encapsulation of protein drugs. The microparticle characteristics can be influential factors for consecutive sustained drug release from the starch matrix and impact its ability to be coated by poly(D,L‐lactide‐co‐glycolide). In this study, six types of starch microparticles were investigated and characterized. Desired qualities of the microspheres such as spherical form of the particles, well‐defined and sharp particle contours were coincident with coarse surface morphology, sharp and distinct peaks in DSC and X‐ray graphs. It was concluded that the quality of the starch microparticles was influenced by molecular properties of the starch material as well as type of buffer, and these factors were related to recrystallization kinetics, amount and quality of ordered/crystalline structure of final starch microspheres and their microscopic appearance.
Chemical and Physical Properties of Kiwifruit (Actinidia deliciosa) Starch
Authors: Stevenson David G. , Johnson Scott R. , Jane Jay‐lin , Inglett George E.
Published: June 2006

Chemical and physical properties of kiwifruit (Actinidia deliciosa var. ‘Hayward’) starch were studied. Kiwifruit starch granules were compound, irregular or dome‐shaped with diameters predominantly 4–5 µm or 7–9 µm. Kiwifruit starch exhibited B‐type X‐ray diffraction pattern, an apparent amylose content of 43.1% and absolute amylose content of 18.8%. Kiwifruit amylopectins, relative to other starches, had low weight‐average molecular weight (7.4×107), and gyration radius (200 nm). Average amylopectin branch chain‐length was long (DP 28.6). Onset and peak gelatinization temperatures were 68.9°C and 73.0°C, respectively, and gelatinization enthalpy was high (18.5 J/g). Amylose‐lipid thermal transition was observed. Starch retrograded for 7 d at 4°C had a very high peak melting temperature (60.7°C). Peak (250 RVU), final (238 RVU) and setback (94 RVU) viscosity of 8% kiwifruit starch paste was high relative to other starches and pasting temperature (69.7°C) was marginally higher than onset gelatinization temperature. High paste viscosities and low pasting temperature could give kiwifruit starch some advantages over many cereal starches.
Study of Protein Detection and Ultrastructure of Brazilian Rice Starch during Alkaline Extraction
Authors: Cardoso Mateus B. , Samios Dimitrios , Silveira Nádya P.
Published: June 2006

Alkaline extraction of Brazilian rice starch was studied. UV/Vis and fluorescence spectroscopy were employed as an innovative way for protein detection during the extraction. Moreover, the results were compared to the traditional biuret colorimetric test. In parallel, the ultrastructure of starch was monitored by small angle X‐ray scattering (SAXS) during every extraction step. A progressive reduction of the granules organization was observed, which was also detected by the loss of birefringence under polarized light. The external integrity of starch granules after complete removal of proteins was maintained, as verified by scanning electron microscopy (SEM). The size of the granules, determined by the Mie scattering method varied between 3 and 8 µm.
Three‐dimensional ultrasound assessment of the cervix for predicting time to spontaneous onset of labor and time to delivery in prolonged pregnancy
Authors: Rovas L. , Sladkevicius P. , Strobel E. , De Smet F. , De Moor B. , Valentin L.
Published: June 2006

Objectives

To determine whether three‐dimensional (3D) ultrasound including power Doppler examination of the cervix is useful for predicting time to spontaneous onset of labor or time to delivery in prolonged pregnancy.

Methods

A prospective study was conducted in 60 women who went into spontaneous labor. All underwent transvaginal 3D power Doppler ultrasound examination of the cervix immediately before a prolonged‐pregnancy check‐up at ≥ 41 + 5 gestational weeks. Univariate and multivariate logistic regression analysis was used to determine which of the following variables predicted spontaneous onset of labor > 24 h and > 48 h and vaginal delivery > 48 h and > 60 h: length, anteroposterior (AP) diameter and width of the cervix and of any cervical funneling; cervical volume (cm3); vascularization index (VI); flow index (FI); vascularization flow index (VFI); parity; and Bishop score. Multivariate logistic regression analysis was carried out both with and without Bishop score as a predictive variable. Receiver–operating characteristics (ROC) curves were used to describe the diagnostic performance of the tests.

Results

The areas under the ROC curves for Bishop score, cervical length, and logistic regression models did not differ significantly (areas ranging from 0.72 to 0.82). If Bishop score was not included in the logistic regression model, cervical length, VI and FI independently predicted delivery > 48 h, the likelihood increasing with increasing cervical length, decreasing VI and increasing FI.

Conclusions

In prolonged pregnancy cervical vascularization as estimated by 3D power Doppler ultrasound is related to time to delivery > 48 h, but the likelihood of delivery > 48 h can be predicted equally well using Bishop score alone or sonographic cervical length alone Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Portable EDXRF surface mapping of sulfate concentration on Michelangelo's David
Authors: Castellano Alfredo , Buccolieri Giovanni , Quarta Stefano , Donativi Marina
Published: June 2006

The study presented in this paper was carried out within a large international project founded in the context of the Michelangelo's David's 500th anniversary celebration. A group of experts analysed Michelangelo's masterpiece with several techniques with the aim of helping restorers to choose the most suitable treatment for cleaning of the statue. The task of the present team was to map the possible presence of sulfur (as sulfates) on the surface of the sculpture due to pollution effects. A portable energy‐dispersive x‐ray fluorescence (EDXRF) system was used. The EDXRF technique is not only non‐destructive, sensitive and capable of simultaneous multi‐elemental analysis but also, in its portable version, it allows the analysis of many areas before, during and after restoration. A large number of measurements were made to obtain an overall picture of the sulfur distribution on the sculpture and then further measurements were made at selected strategic points. After applying different removal procedures at each of these points, the measurements were repeated to obtain a quantitative evaluation of the effectiveness of each cleaning procedures. The results are presented and discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Modern Laparoscopy and the Archery Episode in the Greatest Epic of India: Mahabarata1
Authors: Natarajan K.
Published: June 2006

The laparoscopic surgeon is trained to acquire advanced skills to perform the complicated laparoscopic surgery of the target tissue in a three‐dimensional (3D) space by viewing its two‐dimensional (2D) video image. This technique finds its parallel in a very ancient archery episode portrayed in the longest and the greatest Indian epic, Mahabarata. In this epic, Arjuna, the master archer, is required to employ the strategy of aiming at the eye of a target fish rotating above his head by viewing its reflected image below in water; of course, all this to win the hand of a beautiful princess! Arjuna is so trained that he cannot but excel in focusing his attention on his target. A comparative study of the laparoscopic surgeon and the ancient master archer is done in this paper with a view to throwing light on the interesting similarities between the archer and the modern laparoscopic surgeon with respect to training methods, skills, and techniques.
Improvement in serial cardiopulmonary exercise testing following enzyme replacement therapy in Fabry disease
Authors: Bierer Gregory , Balfe David , Wilcox William R. , Mosenifar Zab
Published: June 2006

Background. Fabry disease is an X‐linked genetic disorder resulting in the accumulation of glycosphingolipids in various organs, leading to exercise intolerance and early mortality. Enzyme replacement therapy (ERT) has recently been approved for use in Fabry patients. Goals of study. To assess baseline cardiopulmonary exercise characteristics in both invasive and noninvasive tests and to study the impact of ERT on exercise. Methods. A total of 15 patients with Fabry disease underwent baseline cardiopulmonary exercise tests. Six patients were randomized 2:1 to receive either ERT or placebo. We performed serial cardiopulmonary exercise tests at baseline and every 3 months over a period of at least 18 months. The baseline test was compared to the last two exercise tests for each patient. Results. Mean age was 32 years. Mean VO2 max was 1.680 ± 0.67 L/min and increased by 0.459 ± 0.64 L/min in the patients receiving ERT. Mean VO2 max was 1.462 ± 0.25 L/min and decreased by 0.116 ± 0.44 L/min in patients on placebo. Mean oxygen pulse (VO2/HR) increased by 1.71 with enzyme, but increased only 0.025 in patients taking placebo. Estimated stroke volume (SV) increased by 10 ml in patients on ERT. Conclusions. In this small cohort, exercise tolerance increased in patients receiving enzyme replacement therapy. Cardiopulmonary exercise testing is a useful test in measuring the response to therapy in Fabry disease patients.
Quadrilateral Space Syndrome Caused by a Humeral Osteochondroma: A Case Report and Review of Literature
Authors: Cirpar Meric , Gudemez Eftal , Cetik Ozgur , Uslu Murad , Eksioglu Fatih
Published: June 2006

Quadrilateral space syndrome (QSS) is a rare condition in which the posterior humeral circumflex artery and the axillary nerve are entrapped within the quadrilateral space. The main causes of the entrapment are abnormal fibrous bands and hypertrophy of the muscular boundaries. Many other space-occupying causes such as a glenoidal labral cyst or fracture hematoma have been reported in the literature. However, we could not find a report on classical QSS caused by an osteochondroma. The aim of this case report is to attract attention to an unusual etiology of shoulder pain, and to emphasize the importance of physical examination and x-ray imaging before performing more complex attempts for differential diagnosing.
Formal and informal learning situations or practices vs formal and informal ways of learning
Authors: Folkestad Göran
Published: June 2006

During the last decade there has been an awakening interest in considering not only formalised learning situations within institutional settings, but also all the various forms of informal musical learning practices outside schools. Informal musical learning outside institutional settings has been shown to contribute to important knowledge and aspects of music education. In this article, I will examine research studies which in different ways focus on formal and informal learning situations and practices or formal and informal ways of learning. I will consider the relationship between music education as praxis (music pedagogy) and as research, and the relationship between these two facets of music education and the surrounding society. I will identify four different ways of using and defining formal and informal learning, respectively, either explicitly or implicitly, each one focusing on different aspects of learning: (i) the situation, (ii) learning style, (iii) ownership, and (iv) intentionality. Formal – informal should not be regarded as a dichotomy, but rather as the two poles of a continuum; in most learning situations, both these aspects of learning are in various degrees present and interacting. Music education researchers, in order to contribute to the attainment of a multiplicity of learning styles and a cultural diversity in music education, need to focus not only on the formal and informal musical learning in Western societies and cultures, but also to include the full global range of musical learning in popular, world and indigenous music in their studies.
The effects of age, gender and language on children's singing competency
Authors: Mang Esther
Published: June 2006

Literature on children's singing development is largely skewed towards findings based on English-speaking children. The present study aims to fill the gap in research through an investigation of the effects of age, gender and language on the singing competency of Cantonese-speaking children. One hundred and twenty children aged 7 and 9 years participated in the study. Sixty children were Cantonese monolinguals and 60 were English bilinguals. Each child performed individually a criterion song and two independent judges rated the recorded singing performance. Welch's model of Pitch-matching Development (2000) and Rutkowski's Singing Voice Development Measure (1998) were used to evaluate singing competency. Results suggest that melodic singing achievement and the ability to use a singing voice are moderately related singing behaviours. Evidence also suggests that gender and language but not age affects singing competency.
Preservation and development in the transformative zone: Fusing disparate styles and traditions in a pedagogy workshop with Cuban musicians
Authors: Russell Joan
Published: June 2006

This paper builds on the concept that fusion – the blending of styles and traditions resulting in new or hybridised genres – takes place in social interaction in the ‘transformative zone’ (Bresler, 2003). First I explore the issues surrounding the tension that can occur between the need, or desire, to maintain cherished traditions and the need to create and adapt forms of expression (Bebey 1969/1975) that are meaningful to practitioners. Next, I describe a spontaneous act of fusion that occurred during a music pedagogy workshop that I gave to music teachers in Cuba. Blending the tranquil mood of a Hebrew blessing, with lively Cuban polyrhythms the participants created a hybridised genre that reflected Cuban musical traditions and values. I suggest that while the blessing was transformed stylistically, its meaningful aspects were retained in the sense that the experience provided the conditions for a feeling of communion with others and the feelings of happiness that can arise from such communion.
THE LIVES AND ROLES OF WOMEN OF VARIOUS CLASSES IN THE IE OF LATE MEDIEVAL JAPAN
Authors: Goto Michiko
Published: June 2006

In medieval Japan the household became the basic social unit among all classes. In the process, a division of roles also came about: the household head and husband represented the ie to the outside world, while the wife was in charge of its running. The wife's role was highly regarded in the medieval period, but its details have yet to be fully examined. This paper attempts to shed light on how medieval women lived by studying the role of wives and their integral place in ie management. To do this, it is also necessary to examine the relationship between the father's wife and the son's wife, in other words, the mother-in-law and the daughter-in-law. I will look at women from various classes, to the extent the documentation allows, utilizing the diaries of the court nobility, literary works and other documentary, graphic and material evidence.
LEGAL TROUBLES AND THEIR RESOLUTION IN CHINA: THE INTERACTION OF SHUOLIZHE AND XINFUZHE
Authors: Takamizawa Osamu
Published: June 2006

It has long been recognized that, within traditional Chinese law and down to the present, civil disputes have had the potentiality of developing into criminal cases. This essay attempts to draw a dynamic picture of how legal troubles, both civil disputes and minor criminal cases, accelerated into major criminal ones. Section One discusses the pattern of such legal troubles in traditional and modern China. Section Two describes the mode by which such troubles were resolved, arguing that the resolution process is a kind of role-play between a third party, such as mediators, conciliators and judges, and those who are subject to their reasoning, such as plaintiffs and defendants. Section Three studies the conditions under which this operates. Third parties were not trusted, in terms of their fairness or competence, and thus they did not necessarily have the ability to settle disputes. Section Four examines the relation between crime and penalties in relation to these legal troubles, focusing particularly on how terms of punishment favoured lesser options.
When will the Antarctic ozone hole recover?
Authors: Newman Paul A. , Nash Eric R. , Kawa S. Randolph , Montzka Stephen A. , Schauffler Sue M.
Published: June 2006

The Antarctic ozone hole demonstrates large‐scale, man‐made affects on our atmosphere. Surface observations now show that human produced ozone‐depleting substances (ODSs) are declining. The ozone hole should soon start to diminish because of this decline. We demonstrate a parametric model of ozone hole area that is based upon a new algorithm for estimating chlorine and bromine levels over Antarctica and late spring Antarctic stratospheric temperatures. This model explains 95% of the ozone hole area's variance. We then use future ODS levels to predict ozone hole recovery. Full recovery to 1980 levels will occur around 2068 and the area will very slowly decline between 2001 and 2017. Detection of a statistically significant decrease of area will not occur until about 2024. We further show that nominal Antarctic stratospheric greenhouse gas forced temperature change should have a small impact on the ozone hole.
First results from the ionospheric radio occultations of Saturn by the Cassini spacecraft
Authors: Nagy Andrew F. , Kliore Arvydas J. , Marouf Essam , French Richard , Flasar Michael , Rappaport Nicole J. , Anabtawi Aseel , Asmar Sami W. , Johnston Douglas , Barbinis Elias , Goltz Gene , Fleischman Don
Published: June 2006

The first set of near‐equatorial occultations of the Saturn ionosphere was obtained by the Cassini spacecraft between May and September of 2005. The occultations occurred at near‐equatorial latitudes, between 10°N and 10°S, at solar zenith angles from about 84° to 96°. The entry observations correspond to dusk conditions and the exit ones to dawn. An initial look at the data indicates that the average peak densities are lower and the peak altitude higher at dawn than at dusk, possibly the result of ionospheric decay during the night hours. There are also significant differences between individual dawn and dusk occultations; the initial thought is that this variation must be connected to changes in the water inflow into the upper atmosphere and/or variations in the particle impact ionization rates.
Characteristics of the Ross Ice Shelf air stream as depicted in Antarctic Mesoscale Prediction System simulations
Authors: Parish Thomas R. , Cassano John J. , Seefeldt Mark W.
Published: June 2006

Streamlines of the mean annual near‐surface winds over the Antarctic continent suggest a confluent channeling of the drainage flows off the ice sheets and onto the Ross Ice Shelf. A persistent cyclonic circulation to the north of the ice shelf supports a large‐scale pressure field that reinforces the continental drainage flows. Owing to these two processes, an enhanced low‐level airflow is present along the southern and western sections of the Ross Ice Shelf. The resulting air stream, known as the Ross Ice Shelf air stream (RAS), is one of the persistent and prominent low‐level wind features seen in the Antarctic. Real‐time mesoscale simulations of the Antarctic atmosphere and high southern latitudes using a modified version of the Pennsylvania State University/National Center for Atmospheric Research Mesoscale Modeling System have been ongoing since the 1999–2000 austral field season. Model results from the 1‐year period November 2001 to October 2002 have been analyzed to investigate the mean structure and modulation of the Ross Ice Shelf air stream. Analyses of model results show the low‐level air stream over the western Ross Ice Shelf has a wind speed maxima that is linked to the steep topography to the west. Individual cases of strong wind events appear to contain a significant barrier wind component that arises from cold air damming against the Transantarctic Mountains. Cyclones that frequently form in the Ross Sea are shown to establish conditions that promote barrier wind dynamics and thus significantly modulate the intensity of the RAS.
Detection of the trend and seasonal variation in tropospheric NO2 over China
Authors: van der A R. J. , Peters D. H. M. U. , Eskes H. , Boersma K. F. , Van Roozendael M. , De Smedt I. , Kelder H. M.
Published: June 2006

The results of a trend study on the tropospheric NO2 column over China are presented, on the basis of measurements from the satellite instruments GOME and SCIAMACHY. From these observations, monthly averaged tropospheric NO2 distributions are determined for the period 1996 to 2005 on a 1° by 1° grid. A linear model with a seasonal component is used to fit these time series. The variance and the autocorrelation of the noise are used to calculate the significance of the trend. The results show a large growth of tropospheric NO2 over eastern China, especially above the industrial areas with a fast economical growth. For instance, Shanghai had a linear significant increase in NO2 columns of 20% ± 6% per year (reference year 1996) in the period 1996–2005. The seasonal pattern of the NO2 concentration shows a difference between east and west China. In the east a NO2 maximum is found during wintertime, because of chemistry and anthropogenic activity. Contrary to this, in the western part of China the NO2 concentration reaches a maximum in summertime. This spatial difference correlates with the population distribution of China. Since there is negligible anthropogenic activity in west China this difference in seasonality of NO2 is attributed to natural emissions in west China.
Using CO2:CO correlations to improve inverse analyses of carbon fluxes
Authors: Palmer Paul I. , Suntharalingam Parvadha , Jones Dylan B. A. , Jacob Daniel J. , Streets David G. , Fu Qingyan , Vay Stephanie A. , Sachse Glen W.
Published: June 2006

Observed correlations between atmospheric concentrations of CO2 and CO represent potentially powerful information for improving CO2 surface flux estimates through coupled CO2‐CO inverse analyses. We explore the value of these correlations in improving estimates of regional CO2 fluxes in east Asia by using aircraft observations of CO2 and CO from the TRACE‐P campaign over the NW Pacific in March 2001. Our inverse model uses regional CO2 and CO surface fluxes as the state vector, separating biospheric and combustion contributions to CO2. CO2‐CO error correlation coefficients are included in the inversion as off‐diagonal entries in the a priori and observation error covariance matrices. We derive error correlations in a priori combustion source estimates of CO2 and CO by propagating error estimates of fuel consumption rates and emission factors. However, we find that these correlations are weak because CO source uncertainties are mostly determined by emission factors. Observed correlations between atmospheric CO2 and CO concentrations imply corresponding error correlations in the chemical transport model used as the forward model for the inversion. These error correlations in excess of 0.7, as derived from the TRACE‐P data, enable a coupled CO2‐CO inversion to achieve significant improvement over a CO2‐only inversion for quantifying regional fluxes of CO2.
SAR mapping of Burfellshraun: A terrestrial analog for recent volcanism on Mars
Authors: Haack Henning , Rossi Matti J. , Dall Jørgen
Published: June 2006

Images of the Northern plain on Mars have revealed up to 1500 km long lava flows. The low density of impact craters on the lava flows implies that these lava flows were formed during the most recent volcanic activity on Mars. Estimates of the ages of the flows are controversial but generally between 10 and 100 Myr. Parts of the lava flows show smooth kilometer‐sized plates that appear to have rafted on the moving lava flow. We have found a terrestrial analogue with similar features, the Burfellshraun lava flow in Northern Iceland. This is the only known lava flow on Earth where kilometer‐sized rafting plates are observed and constitute the dominating feature. Using a combination of airborne remote sensing data and field observations we have studied the emplacement and physical properties of the flow. On the basis of our observations we have reconstructed the sequence of events that led to the disruption of the lava surface. Our observations show that a ∼45 km2 lava lake, holding about 0.7 km3 of lava, catastrophically collapsed releasing a flood of lava. During the collapse the crust of the lava lake was broken into plates up to a kilometer in width and a few meters thick that floated downstream for almost 10 km.
Radar probing of planetary regoliths: An example from the northern rim of Imbrium basin
Authors: Thompson Thomas W. , Campbell Bruce A. , Ghent Rebecca R. , Hawke B. Ray , Leverington David W.
Published: June 2006

Imaging radar measurements at long wavelengths (e.g., >30 cm) allow deep (up to tens of meters) probing of the physical structure and dielectric properties of planetary regoliths. We illustrate a potential application for a Mars orbital synthetic aperture radar (SAR) using new Earth‐based 70‐cm wavelength radar data for the Moon. The terrae on the northern margin of Mare Imbrium, the Montes Jura region, have diffuse radar backscatter echoes that are 2–4 times weaker at 3.8‐cm, 70‐cm, and 7.5‐m wavelengths than most other lunar nearside terrae. Possible geologic explanations are (1) a pyroclastic deposit associated with sinuous rilles in this region, (2) buried mare basalt or a zone of mixed highland/basaltic debris (cryptomaria), or (3) layers of ejecta associated with the Iridum and Plato impacts that have fewer meter‐sized rocks than typical highlands regolith. While radar data at 3.8‐cm to 7.5‐m wavelengths suggest significant differences between the Montes Jura region and typical highlands, the surface geochemistry and rock abundance inferred from Clementine UV‐VIS data and eclipse thermal images are consistent with other lunar terrae. There is no evidence for enhanced iron abundance, expected for basaltic pyroclastic deposits, near the source vents of the sinuous rilles radial to Plato. The regions of low 70‐cm radar return are consistent with overlapping concentric “haloes” about Iridum and Plato and do not occur preferentially in topographically low areas, as is observed for radar‐mapped cryptomaria. Thus we suggest that the extensive radar‐dark area associated with the Montes Jura region is due to overlapping, rock‐poor ejecta deposits from Iridum and Plato craters. Comparison of the radial extent of low‐radar‐return crater haloes with a model for ejecta thickness shows that these rock‐poor layers are detected by 70‐cm radar where they are on the order of 10 m and thicker. A SAR in orbit about Mars could use similar deep probing to reveal the nature of crater‐ and basin‐related deposits.
An estimation of the electrical characteristics of planetary shallow subsurfaces with TAPIR antennas
Authors: Le Gall A. , Reineix A. , Ciarletti V. , Berthelier J. J. , Ney R. , Dolon F. , Corbel C.
Published: June 2006

In the frame of the NETLANDER program, we have developed the Terrestrial And Planetary Investigation by Radar (TAPIR) imaging ground‐penetrating radar to explore the Martian subsurface at kilometric depths and search for potential water reservoirs. This instrument which is to operate from a fixed lander is based on a new concept which allows one to image the various underground reflectors by determining the direction of propagation of the reflected waves. The electrical parameters of the shallow subsurface (permittivity and conductivity) need to be known to correctly determine the propagation vector. In addition, these electrical parameters can bring valuable information on the nature of the materials close to the surface. The electric antennas of the radar are 35 m long resistively loaded monopoles that are laid on the ground. Their impedance, measured during a dedicated mode of operation of the radar, depends on the electrical parameters of soil and is used to infer the permittivity and conductivity of the upper layer of the subsurface. This paper presents an experimental and theoretical study of the antenna impedance and shows that the frequency profile of the antenna complex impedance can be used to retrieve the geoelectrical characteristics of the soil. Comparisons between a numerical modeling and in situ measurements have been successfully carried over various soils, showing a very good agreement.
Modeling non‐Fickian transport in geological formations as a continuous time random walk
Authors: Berkowitz Brian , Cortis Andrea , Dentz Marco , Scher Harvey
Published: June 2006

Non‐Fickian (or anomalous) transport of contaminants has been observed at field and laboratory scales in a wide variety of porous and fractured geological formations. Over many years a basic challenge to the hydrology community has been to develop a theoretical framework that quantitatively accounts for this widespread phenomenon. Recently, continuous time random walk (CTRW) formulations have been demonstrated to provide general and effective means to quantify non‐Fickian transport. We introduce and develop the CTRW framework from its conceptual picture of transport through its mathematical development to applications relevant to laboratory‐ and field‐scale systems. The CTRW approach contrasts with ones used extensively on the basis of the advection‐dispersion equation and use of upscaling, volume averaging, and homogenization. We examine the underlying assumptions, scope, and differences of these approaches, as well as stochastic formulations, relative to CTRW. We argue why these methods have not been successful in fitting actual measurements. The CTRW has now been developed within the framework of partial differential equations and has been generalized to apply to nonstationary domains and interactions with immobile states (matrix effects). We survey models based on multirate mass transfer (mobile‐immobile) and fractional derivatives and show their connection as subsets within the CTRW framework.
Development of a joint hydrogeophysical inversion approach and application to a contaminated fractured aquifer
Authors: Chen J. , Hubbard S. , Peterson J. , Williams K. , Fienen M. , Jardine P. , Watson D.
Published: June 2006

This paper presents a joint inversion approach for combining crosshole seismic travel time and borehole flowmeter test data to estimate hydrogeological zonation. The approach is applied to a complex, fractured Department of Energy field site located at the Oak Ridge National Laboratory in Tennessee, United States. We consider seismic slowness (the inverse of seismic velocity) and hydrogeological zonation indicators as unknown variables and use a physically based model with unknown parameters to relate the seismic slowness to the zonation indicators. We jointly estimate all the unknown parameters in the model by conditioning them to the crosshole seismic travel times as well as the borehole flowmeter data using a Bayesian model and a Markov chain Monte Carlo sampling method. The fracture zonation estimates are qualitatively compared to bromide tracer breakthrough data and to uranium biostimulation experiment results. The comparison suggests that the joint inversion approach adequately estimated the fractured zonation and that the fracture zonation influenced biostimulation efficacy. Our study suggests that the new joint hydrogeophysical inversion approach is flexible and effective for integrating various types of data sets within complex subsurface environments and that seismic travel time data have the potential to provide valuable information about fracture zonation.
In situ evidence for renitrification in the Arctic lower stratosphere during the polar aura validation experiment (PAVE)
Authors: Dibb Jack E. , Scheuer Eric , Avery Melody , Plant Jim , Sachse Glen
Published: June 2006

In‐situ measurements of nitric acid (HNO3), ozone (O3), and nitrous oxide (N2O) were made from the NASA DC‐8 during the Polar Aura Validation Experiment in January/February 2005. In the lower stratosphere (9–12.5 km, potential temperature 300–350 K) characteristic compact relationships were observed between all three gases. The ratio HNO3/O3 averaged 3.5 (±0.7) ppt/ppb. Samples with enhanced HNO3/O3 (>4.0) were most abundant under the edge of the Arctic Polar vortex in airmasses with enhanced mixing ratios of both gases (>400 ppb O3 and >2000 ppt HNO3) and reduced mixing ratios of N2O (<305 ppb), indicating air from higher levels in the stratosphere. Relationships to N2O in the anomalous samples under the vortex edge indicate that increases in HNO3/O3 reflect renitrification at DC‐8 flight levels, with no indication of significant O3 loss. Renitrified air was only observed at potential temperatures above 340 K, and was most abundant on the PAVE flights on 27 and 29 January.
Three new species of northern Australian Glycine (Fabaceae, Phaseolae), G. gracei, G. montis-douglas and G. syndetika
Authors: Pfeil B. E. , Craven L. A. , Brown A. H. D. , Murray B. G. , Doyle J. J.
Published: June 2006

Three new Australian diploid species in Glycine Willd. are described. Two of these (Glycine gracei B.E.Pfeil & Craven and Glycine montis-douglas B.E.Pfeil & Craven) are endemic to the Northern Territory whereas the third (Glycine syndetika B.E.Pfeil & Craven) is endemic to Queensland. G. montis-douglas is only known from one locality. The genetic affinities of G. gracei and G. syndetika are with other A genome species. The species G. syndetika is the closest relative of a diploid parent of the T2 allotetraploid race of the G. tomentella s.l. Hayata species complex, as well as of allotetraploid G. pescadrensis Hayata, which is here formally reinstated from synonymy. Images are included of the leaflet venation for several species discussed in the paper. Thus, the treatment incorporates evidence from morphology, cytology, DNA sequences and crossing experiments. A key to the subgenera and to the species within Glycine subgenus Glycine is provided, which includes all 25 described Australian taxa.
Systematic studies in Lepidosperma (Cyperaceae: Schoeneae) with particular reference to L. laterale
Authors: Hodgon John , Bruhl Jeremy J. , Wilson Karen L.
Published: June 2006

Lepidosperma laterale exhibits much morphological variation across its geographical range. This study included L. laterale, and morphologically similar species, as well as several comparator species. Phenetic analyses based on 27 morphological and 25 vegetative anatomical characteristics were undertaken in an attempt to resolve taxonomic issues within the study group. Evidence for broadening the delimitation of L. laterale is strong as OTUs of this variable species formed a group with indistinct clusters in all analyses. The mixed, diffuse clusters obtained of OTUs of specimens identified as L. gunnii with specimens of L. laterale suggest that the species limits of the former lie within the limits of the latter. Specimens of most other study group taxa formed relatively cohesive, discrete clusters in ordination and cluster analyses. The results provide strong support for recognition of L. sp. Whian Whian S.F. (J. Hodgon 331 & D.M. Hodgon) and L. sp. Mt Coolum (P.R. Sharpe 5605A) as new species.