bluuebunny/crossref_metadata_2025 huggingface dataset:
Intersection cuts from outer polars of truncated cubes
Authors: Balas Egon , Zoltners Andris
Published: May 2007

A truncated cube, by which we mean the convex hull of a subset of the vertices of the unit cube, has an outer polar whose facets are a subset of the facets of the octahedron (the outer polar of the cube). We discuss procedures for generating valid truncations of the cube from the problem constraints, in the case of 0‐1 integer programs, and for intersecting the halflines defined by the constraints that are tight for a basic solution to the linear program, with successive facets of the outer polars of these truncated cubes. The cutting planes obtained in this way are compared to other cuts.
Developing an optimal repair‐replacement strategy for pallets
Authors: Von Lanzenauer Christoph Haehling , Wright Don D.
Published: May 2007

A Markovian model is presented for the development of an optimal repair‐replacement policy for the situation requiring a decision only at failure. The problem is characterized by the presence of growth which is integrated into the formulation. The model is applied to an actual problem, with data analysis and results given. Substantial savings are indicated.
Approximating partial inverse moments for certain normal variates with an application to decaying inventories
Authors: Nahmias Steven , Wang Shan Shan
Published: May 2007

This paper considers the problem of computing E(X−n; X > t) when X is a normal variate having the property that the mean is substantially larger than the standard deviation. An approximation is developed which is determined from the mean, standard deviation, and the cumulative standard normal distribution. Computations comparing the approximate moments with the actual are reported for various values of the relevant parameters. These results are applied to the problem of computing the expected number of shortages in a lead‐time for a single product which exhibits continuous exponential decay.
There are many roads
Authors: Wood Robert C.
Published: May 2007

A single government, federation or council may discover way to the utopian community.
A transit paradox
Authors: Fitch Lyle C.
Published: May 2007

Technology works wonders in sky but makes little improvement in city transportation.
Leadership training
Authors: Dorothy  , Mial H. Curtis
Published: May 2007

Laboratory seeks new approaches to stimulate citizen awareness of dynamic, changing forces.
Vascular endothelial growth factor (VEGF) receptor antibody bevacizumab (avastin) induces regression of renal cell carcinoma in an adolescent resulting in residual tumorectomy
Authors: Joshi Divya‐Devi , Banerjee Tarit
Published: May 2007

Renal cell carcinoma is a chemo‐ and radiation‐resistant malignancy that is very rare in childhood. In advanced cases, survival is extremely poor, but cure can be achieved with complete tumorectomy. We report a 14‐year‐old female with left renal cell carcinoma, with regional lymphadenopathy extending up to the diaphragm. Complete tumor resection was impossible. The tumor progressed after 10 months of treatment with high‐dose interleukin‐2. After 7 months of outpatient vascular endothelial growth factor receptor antibody bevacizumab and no significant adverse effects, dramatic tumor shrinkage enabled complete resection. Pediatr Blood Cancer 2008;50:903–904. © 2007 Wiley‐Liss, Inc.
Protein expression profiles of Bos taurus blood and lymphatic vessel endothelial cells
Authors: Bianchi Laura , Lorenzoni Paola , Bini Luca , Weber Elisabetta , Tani Chiara , Rossi Antonella , Agliano Margherita , Pallini Vitaliano , Sacchi Giovanni
Published: May 2007

The endothelium is a metabolically active organ that regulates the interaction between blood or lymph and the vessel or the surrounding tissue. Blood endothelium has been the object of many investigations whereas lymphatic endothelium biology is yet poorly understood. This report deals with a proteomic approach to the characterization and comparative analysis of lymphatic and blood vessel endothelial cells (ECs). By 2‐DE we visualized the protein profiles of EC extracts from the thoracic aorta, inferior vena cava, and thoracic duct of Bos taurus. The three obtained electropherograms were then analyzed by specific software, and 113 quantitative and 25 qualitative differences were detected between the three endothelial gels. The cluster analysis of qualitative and quantitative differences evidenced the protein pattern of lymphatic ECs to be more similar to the venous than to the arterial one. Moreover, venous ECs were interestingly found showing a protein expression profile more similar to the lymphatic ECs than to the arterial ones. We also identified 64 protein spots by MALDI‐TOF MS and ESI‐IT MS/MS and three reference maps of bovine endothelium were obtained. The functional implications of the identified proteins in vascular endothelial biology are discussed.
Reentrant superconductivity in the strong coupling limit
Authors: Gorczyca A. , Mierzejewski M.
Published: May 2007

The usual approaches to the reentrant superconductivity are based on the mean field approximation. Here, we investigate this effect carrying out exact diagonalization of finite systems. We have found a nonmonotonic field dependence of the pair susceptibility both in the weak and strong coupling limit. This result strongly supports the possible onset of the reentrant superconductivity in the presence of strong magnetic field. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the way to InGaN quantum dots embedded into monolithic nitride cavities
Authors: Sebald K. , Lohmeyer H. , Gutowski J. , Yamaguchi T. , Kruse C. , Hommel D. , Wiersig J. , Jahnke F.
Published: May 2007

We present photoluminescence measurements on single InGaN quantum dots (QDs) grown by metalorganic vapor phase epitaxy, and on monolithicly grown GaN‐based quantum well airpost pillar microcavities. The observed sharp emission lines of the quantum dots are characterized by excitation density dependent measurements. The photoluminescence of individual quantum dots can easily be detected for temperatures up to 150 K. The micro‐photoluminescence measurements on microcavities reveal three‐dimensional confined optical modes which are not seen in the luminescence of the simply planar cavity. The realization of rather temperature stable QDs as well as of nitride based microcavity samples are promising with respect to the intended implementation of QD layers into microcavities. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoluminescence and optical reflectance investigation of semipolar and nonpolar GaN
Authors: Kojima Kazunobu , Ueda Masaya , Funato Mitsuru , Kawakami Yoichi
Published: May 2007

Optical properties of semipolar and nonpolar unstrained GaN are studied employing photoluminescence, optical reflectance and the k·p perturbation theory in this article. We find that donor bound and free A excitons show a strong polarization for photoluminescence in {11$ \bar 2 $2} and {10$ \bar 1 $0} GaN, while that of B excitons has only a little dependence on crystal orientations. Optical reflectance measurements are also performed to investigate resonance energies and transition probabilities of free excitons. The oscillator strength of A and C excitons has a strong dependency on the angle between c‐axis and growth direction, while that of B is nearly unchanged in every unstrained GaN plane. The experimental results can be well explained by our k·p calculations. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetotransport in AlGaN/GaN and AlGaN/AlN/GaN heterostructures
Authors: Umana‐Membreno G. A. , Parish G. , Nener B. D. , Buttari D. , Keller S. , Mishra U. K.
Published: May 2007

Two‐dimensional electron gas transport in AlN/GaN and AlGaN/GaN heterostructures has been investigated employing geometrical magnetoresistance measurements and quantitative mobility‐spectrum analysis. The channel magnetoresistance of ungated four‐terminal test structures, with an effective width to length ratio of 10, was measured using pulsed drain‐to‐source voltages equivalent to longitudinal electric fields up to 750 V/cm at magnetic field intensities up to 12 T and sample temperatures from 10 to 300 K. Two distinct electron populations, with significantly different mobilities, are shown to be present in the channel of both AlGaN/AlN/GaN and AlGaN/GaN heterostructures. It is also shown that application of longitudinal electric fields up to 750 V/cm cause a reduction in the mobility of these carrier populations and change the shape of mobility spectrum of the dominant electron population. The origin of these carrier populations is discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermal and chemical stabilities of In‐ and N‐polar InN surfaces
Authors: Naoi H. , Muto D. , Hioka T. , Hayakawa Y. , Suzuki A. , Araki T. , Nanishi Y.
Published: May 2007

We have investigated the thermal and the chemical stabilities of In‐ and N‐polar InN surfaces by treating InN films in several environments: annealing in vacuum, etching in KOH solution, and irradiating with atomic hydrogen (H*). For the annealing case, In‐polar films mostly disappeared after 5 min at 550 °C and In‐droplets of various sizes were left on the surface of the samples, whereas N‐polar films showed no noticeable change in thickness and only tiny In‐droplets were formed on the surface. For the KOH case, N‐polar films developed rough surface morphologies by the emergence of hexagonal pyramids, whereas In‐polar films were not etched noticeably. In‐polar films also exhibited a much lower reactivity to H* than that of N‐polar films. As a result, the N‐polar surface was thermally more stable than the In‐polar surface, whereas the In‐polar surface appeared to be chemically more stable than the N‐polar surface. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Application of Chromatography and Chemometrics to Estimate Lipophilicity of Ionic Liquid Cations
Authors: Studzińska Sylwia , Stepnowski Piotr , Buszewski Bogusław
Published: May 2007

The hydrophobicity of ionic liquids, an important physical property, is currently attracting attention of scientists particularly for chemical–biological interactions. In this report, the hydrophobicity of selected ionic liquid (only imidazolium based) cations has been investigated according to some methods: chromatographic analysis, statistical, and chemometric approach. As a consequence, the lipophilicity, which is one of the important factors in biological activity of analyzed compounds, can be established. For that purpose, butyl, octyl, octadecyl, mixed, alkylamide, and cholesterolic packings were chosen and applied to the analysis of eight most commonly used ionic liquid cations. The use of different experimental and theoretical methods allow the estimation of ionic liquids properties. In the present study, chemometric and statistical methods have also been used for the comparison of hydrophobic or hydrophilic character of analyzed compounds and also to estimate their biological activity.
Ab initio investigation of the solvent and electron correlation effects on the geometries and first hyperpolarizabilities of push–pull oligomers
Authors: Perpète Eric A. , Jacquemin Denis
Published: May 2007

Using the HF and MP2 approaches, we have determined the ground‐state geometry and first hyperpolarizability of increasingly long push–pull polyacetylene oligomers. The bulk solvent effects have been assessed at both levels of theory through the Polarizable Continuum Model. For the first hyperpolarizability, the resulting 16 combination of theoretical levels of computation have been compared to evaluate the importance of individual corrections, as well as their additive/ multiplicative character. It turns out that the inclusion of bulk solvent effects is essential for an accurate estimate of the nonlinear optics properties of these push–pull derivatives. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Accuracy of density fitting in calculation of two‐electron repulsion integrals in periodic systems
Authors: Milko Matúš , Noga Jozef , Varga Štefan
Published: May 2007

Recently implemented approach to treat the two‐electron (Coulomb) integrals in periodic systems via density fitting has been examined using Hartree‐‐Fock calculations for model systems including trans‐polyacetylene, poly(methineimine), and trans‐polycyanoborane. At the moment, the exchange part of the Fock operator has been taken exact. In addition to total energies, the performance has been assessed for electron densities, main parameters of the band structure as well as for the topology of selected important bands. DZP and 6‐31G** atomic orbital basis sets were combined with different auxiliary sets including standard ones optimized for molecules. For the purpose of systematic comparisons also auxiliary bases based on the correlation consistent cc‐pVXZ and cc‐pCVXZ hierarchies have been examined. Though these hierarchies were not designed for density fitting they perform fairly well, too, exhibiting an exponential convergence behavior with the increasing cardinal number. It is shown that for bands of chemical interest the band structure is well reproduced even with quite small auxiliary sets. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
A force field for simulating ethanol adsorption on Au(111) surfaces. A DFT study
Authors: Fartaria Rui P. S. , Freitas Filomena F. M. , Silva Fernandes Fernando M. S.
Published: May 2007

The development of a DFT force field to describe the adsorption of ethanol on Au(111) surfaces is presented. An analytical potential energy function is proposed based on fitting the DFT results by means of genetic algorithms. A preliminary test of the force field by Monte Carlo simulations shows a good consistency between the DFT and simulation results. They are also related to previous theoretical and spectroscopic studies on the adsorption of methanol and ethanol on gold clusters. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Statistical education for medical students—Concepts are what remain when the details are forgotten
Authors: Herman Amir , Notzer Netta , Libman Zipi , Braunstein Rony , Steinberg David M.
Published: May 2007

Teaching statistics to medical students is a challenging and often unrewarding task. However, few would argue the need for statistics in the medical school curriculum. In recent years, there has been a growing call for teaching only statistical concepts in medical schools. We strongly oppose this opinion and offer an alternative approach. In this article, we present our experience in teaching statistics to medical students at the Sackler School of Medicine, Tel‐Aviv University, Israel. We then present the results of a recently held survey regarding the long‐term contribution of the statistical curriculum to our
students in different phases of their studies. We conclude by suggesting a new integrative statistical program, which incorporates the study of statistics into the entire medical curriculum. Copyright © 2007 John Wiley & Sons, Ltd.
Harmonizing ISO/IEC 15504 and CMMI
Authors: Rout Terence P. , Tuffley Angela
Published: May 2007

The requirements for conformance of a process model to the international standard for process assessment, ISO/IEC 15504, cover a broad range. The most significant of these is the need to establish a complete and unambiguous mapping between the Process Assessment Model and the relevant Process Reference Model and the Measurement Framework described in the Standard. This is required to support the development of a mechanism for translating the outputs from an assessment using the Process Assessment Model into the standard process profiles defined in ISO/IEC 15504. This article reports the results of an analysis of the relationship between CMMI®, as a ‘candidate conformant Process Assessment Model’, relative to the Measurement Framework defined in ISO/IEC 15504‐2, and the Process Reference Model described in ISO/IEC 12207 Amd 1/2. It is shown that, while in general terms a complete mapping can be established, there are specific areas where coverage is weak. Use of CMMI as a Process Assessment Model in ISO/IEC 15504 Conformant assessments will need to take account of these issues. Copyright © 2007 John Wiley & Sons, Ltd.
Mitochondria and Neurodegeneration
Authors: Petrozzi Lucia , Ricci Giulia , Giglioli Noemi J. , Siciliano Gabriele , Mancuso Michelangelo
Published: May 2007

Many lines of evidence suggest that mitochondria have a central role in ageing-related neurodegenerative diseases. However, despite the evidence of morphological, biochemical and molecular abnormalities in mitochondria in various tissues of patients with neurodegenerative disorders, the question “is mitochondrial dysfunction a necessary step in neurodegeneration?” is still unanswered. In this review, we highlight some of the major neurodegenerative disorders (Alzheimer's disease, Parkinson's disease, Amyotrophic lateral sclerosis and Huntington's disease) and discuss the role of the mitochondria in the pathogenetic cascade leading to neurodegeneration.
Infantile Mitochondrial Disorders
Authors: Carrozzo Rosalba , Piemonte Fiorella , Tessa Alessandra , Lucioli Simona , Rizza Teresa , Meschini Maria Chiara , Fattori Fabiana , Santorelli Filippo M.
Published: May 2007

Mitochondrial disorders encompass any medical specialty and affect patients at any age. Likewise, the spectrum of clinical and genetic signatures of these disorders is ample, making a precise diagnosis difficult. We will report some of the major clinical phenotypes observed in infancy, their underlining molecular features, and will propose an approach to reach a more complete diagnosis.
Introduction of asymbiotically propagated seedlings of Cephalanthera falcata (Orchidaceae) into natural habitat and investigation of colonized mycorrhizal fungi
Authors: Yamato Masahide , Iwase Koji
Published: May 2007

Asymbiotic seedling propagation and introduction of seedlings into a natural habitat were achieved for Cephalanthera falcata. For immature seeds collected 65 days after pollination, high germination rate (av. 50%) was achieved on Hyponex agar medium plates. Root development occurred in about 10% of the protocorms 5 months after seed sowing. Rooted protocorms were transferred to a culture bottle containing 100 ml of the Hyponex agar medium and incubated continually. In about 30% of the transferred individuals, shoot height reached 1.5–2 cm 8 months after the transfer. After acclimatization in wet vermiculite at 4°C for 6 months, 135 individuals were planted in a natural stand of C. falcata in mid February 2001. Shoot appearance rate was 44.4% at the first year and flowering was noted in some plants. At the fifth year, shoots with an average height of 21.6 cm still appeared in four plants, and flowering was noted in three of them. Colonization of mycorrhizal fungi was examined in two of them as well as one wild plant, in which the mycorrhizal fungi were identified to be in Thelephoraceae or Russulaceae. These fungi are known to form ectomycorrhiza with trees, and thus a tripartnership symbiosis consisting of C. falcata, mycorrhizal fungi and trees was suggested. The involvement of ectomycorrhizal fungi might be the reason for the low survival rate in the field experiment, because the distribution of ectomycorrhizal fungi relevant to this orchid is assumed to be uneven. The possibility of introducing artificially propagated orchids into natural habitats was discussed.
Custom-made Articulating Spacer in Two-stage Revision Total Knee Arthroplasty. An Early Follow-up of 14 Cases of at Least 1 Year after Surgery
Authors: Pascale Valerio , Pascale Walter
Published: May 2007

Total knee replacement (TKR) infection represents only a small percentage of all the potential complications in joint replacement, but one that can lead to disastrous consequences. Two-stage revision, which has been proven to be the most effective technique in eradicating infection, includes prosthesis removal, positioning of an antibiotic-loaded spacer, and systemic antimicrobial therapy for at least 6 weeks. It has been suggested that there is better performance in terms of range of motion, pain, extensor mechanism shortening, and spacer-related bone loss if articulating spacers are used instead of fixed spacers. In this paper, we describe our results in two-stage revision of infected total knee arthroplasty with a minimum follow-up of 12 months on 14 patients treated by antibiotic-loaded custom-made articulating spacer as described by Villanueva et al. (Acta Orthop 77(2):329–332, 2006). The mean flexion achieved after the second stage of the revision was 120°, ranging from 97° to 130°. The mean Hospital for Special Surgery score was 84. At 1 year after surgery, none of the knees showed any evidence of recurrence of the infection. Articulating spacers are a suitable alternative to fixed spacers with good range of motion after reimplantation and effectiveness against total knee replacement deep infections.
Classification of Adipose Tissue Species using Raman Spectroscopy
Authors: Beattie J. Renwick , Bell Steven E. J. , Borggaard Claus , Fearon Anna M. , Moss Bruce W.
Published: May 2007

In this study multivariate analysis of Raman spectra has been used to classify adipose tissue from four different species (chicken, beef, lamb and pork). The adipose samples were dissected from the carcass and their spectra recorded without further preparation. 102 samples were used to create and compare a range of statistical models, which were then tested on 153 independent samples. Of the classical multivariate methods employed, Partial Least Squares Discriminant Analysis (PLSDA) performed best with 99.6% correct classification of species in the test set compared with 96.7% for Principal Component Linear Discrimination Analysis (PCLDA). Kohenen and Feed‐forward artificial neural networks compared well with the PLSDA, giving 98.4 and 99.2% correct classification, respectively.
Over‐expression of heat shock protein 27 attenuates doxorubicin‐induced cardiac dysfunction in mice
Authors: Liu Li , Zhang Xiaojin , Qian Bo , Min Xiaoyan , Gao Xiang , Li Chuanfu , Cheng Yunlin , Huang Jun
Published: May 2007

Background

Oxidative stress and myocyte apoptosis are thought to play an important role in the pathogenesis, progression and prognosis of heart failure (HF). Heat shock protein 27 (Hsp27) has been found to confer resistance to oxidative stress in cultured cells; however, the role of Hsp27 in in‐vivo hearts remains to be determined.

Aim

To investigate the effects of Hsp27 over‐expression on doxorubicin‐induced HF.

Methods and Results

Transgenic mice (TG) with cardiac specific over‐expression of Hsp27 and their wild type littermates (WT) were challenged with doxorubicin (25 mg/kg, IP) to induce HF. At day 5, TG mice had significantly improved cardiac function and viability and decreased loss of heart weight following doxorubicin exposure compared with WT. In another parallel experiment, doxorubicin‐induced increased levels of reactive oxygen species, protein carbonylation, apoptosis and morphologic changes were detected in the mitochondria in WT hearts, whereas these effects were markedly attenuated in TG hearts. In addition, upregulation of heat shock protein 70 and heme oxygenase‐1 was present in the TG hearts after doxorubicin stimulation in comparison to WT hearts.

Conclusion

These findings indicate that Hsp27 may play a key role in resistance to doxorubicin‐induced cardiac dysfunction.
Targeted deletion of the osteoclast protein‐tyrosine phosphatase (PTP‐oc) promoter prevents RANKL‐mediated osteoclastic differentiation of RAW264.7 cells
Authors: Yang Jeannie H. , Amoui Mehran , Lau K.-H. William
Published: May 2007

An osteoclastic protein‐tyrosine phosphatase, PTP‐oc, shares the same gene with a renal PTP, Glepp1. This study demonstrated that targeted deletion of PTP‐oc promoter by homologous recombination in RAW264.7 cells completely abolished PTP‐oc expression without affecting Glepp1 expression. This strategy to inhibit PTP‐oc function has three advantages over commonly used gene knock down strategies (e.g., small interference RNA). This strategy: (1) yielded cells completely devoid of PTP‐oc, (2) had no off‐target gene silencing effects, and (3) did not affect Glepp1 expression. The inability of PTP‐oc‐deficient RAW264.7 cells to undergo RANKL‐mediated osteoclastic differentiation confirmed a regulatory role for PTP‐oc in RANKL‐mediated osteoclast differentiation.
Neurexin‐1 is required for synapse formation and larvae associative learning in Drosophila
Authors: Zeng Xiankun , Sun Mingkuan , Liu Li , Chen Fading , Wei Liuchan , Xie Wei
Published: May 2007

Neurexins are highly polymorphic cell‐surface adhesive molecules in neurons. In cultured mammalian cell system, they were found to be involved in synaptogenesis. Here, we report for the first time that Drosophila neurexin is required for synapse formation and associative learning in larvae. Drosophila genome encodes a single functional neurexin (CG7050; Neurexin‐1 or Nrx‐1), which is a homolog of vertebrate α‐neurexin. Neurexin‐1 is expressed in central nervous system and highly enriched in synaptic regions of the ventral ganglion and brain. Neurexin‐1 null mutants are viable and fertile, but have shortened lifespan. The synapse number is decreased in central nervous system in Neurexin‐1 null mutants. In addition, Neurexin‐1 null mutants exhibit associative learning defect in larvae.
Combinatorial selection of a RNA thioaptamer that binds to Venezuelan equine encephalitis virus capsid protein
Authors: Kang Jonghoon , Lee Myung Soog , Watowich Stanley J. , Gorenstein David G.
Published: May 2007

A phosphorothioate RNA aptamer (thioaptamer) targeting the capsid protein of Venezuelan equine encephalitis virus (VEEV) was isolated by in vitro combinatorial selection. The selected thioaptamer had a strong binding affinity (∼7 nM) and high specificity for the target protein. For the binding to the protein, the overall tertiary structure of the thioaptamer is required. We introduce two theoretical methods to examine the effect of phosphorothioate modification on the enhancement of binding affinity and one experimental method to examine the nature of the multiple bands of thioaptamer in a native gel.
Camellia oil and its distillate fractions effectively inhibit the spontaneous metastasis of mouse melanoma BL6 cells
Authors: Miura Daisaku , Kida Yoshishige , Nojima Hiroshi
Published: May 2007

We previously reported that daily intraperitoneal injections of oleamide weakly inhibits the spontaneous metastasis of BL6 cells by blocking the gap junction‐mediated intercellular communications (GJIC) of connexin 26 (Cx26). In the present study, we tested camellia oil, olive oil and cottonseed oil which are rich in oleamide‐like oleic acid for their inhibitory potency on Cx26‐mediated GJIC and spontaneous metastasis of BL6 cells. We found that camellia oil, olive oil and cottonseed oil, and their distillate fractions inhibited Cx26‐mediated GJIC. We also showed that daily intraperitoneal injection of camellia oil and its distillate fractions more potently inhibited spontaneous lung metastasis of BL6 cells than oleamide. Moreover, a daily oral administration of camellia oil distillate fraction effectively inhibited spontaneous metastasis. Notably, even camellia Tempura‐oil, a commercially available food, weakly inhibited the spontaneous metastasis of BL6 cells. Since these oils are used as foods and are quite safe, we propose that they could be used as supplements to protect patients from lung metastasis of melanomas.
Increased postpartum hemorrhage rates in Australia
Authors: Ford J.B. , Roberts C.L. , Simpson J.M. , Vaughan J. , Cameron C.A.
Published: May 2007

Objective: To determine whether changes in risk factors for postpartum hemorrhage (PPH) over time are associated with a rise in postpartum hemorrhage rates. Methods: Population‐based study using linked hospital discharge and birth records from New South Wales, Australia for 752,374 women giving birth, 1994–2002. Analyses include a description of trends and regression analysis of risk factors for postpartum hemorrhage and comparison of predicted and observed rates of postpartum hemorrhage over time. Results: Increasing proportions of women aged 35 years or older, born overseas, nulliparous, having cesarean births, having inductions and/or epidurals, postterm deliveries and large babies were evident. Observed postpartum hemorrhage rates increased from 4.7 to 6.0 per 100 births (P < 0.001) while expected rates, adjusted for covariates, remained steady (P = 0.28). Conclusion: Increases in postpartum hemorrhage are not explained by the changing risk profile of women. It may be that changes in management and/or reporting of postpartum hemorrhage have resulted in higher postpartum hemorrhage rates.
Cold Intolerance Following Median and Ulnar Nerve Injuries: Prognosis and Predictors
Authors: RUIJS A. C. J. , JAQUET J-B. , VAN RIEL W. G. , DAANEN H. A. M. , HOVIUS S. E. R.
Published: May 2007

This study describes the predictors for cold intolerance and the relationship to sensory recovery after median and ulnar nerve injuries. The study population consisted of 107 patients 2 to 10 years after median, ulnar or combined median and ulnar nerve injuries. Patients were asked to fill out the Cold Intolerance Severity Score (CISS) questionnaire and sensory recovery was measured using Semmes–Weinstein monofilaments. Fifty-six percent of the patients with a single nerve injury and 70% with a combined nerve injury suffered abnormal cold intolerance. Patients with no return of sensation had dramatically higher CISS-scores than patients with normal sensory recovery. Females had higher CISS scores post-injury than males. Cold intolerance did not diminish over the years. Patients with higher CISS scores needed more time to return to their work. Age, additional arterial injury, site or type of the injury and dominance of the hand were not found to have a significant influence on cold intolerance.
Microvasculature of the Urinary Bladder of the Dog: A Study Using Vascular Corrosion Casting
Authors: Hossler Fred E. , Kao Race L.
Published: May 2007

The urinary bladder is an unusual organ in that its normal function includes filling and emptying with alternating changes in internal pressure. Although fluctuations in blood flow to the bladder wall are known to accompany these changes, detailed descriptions of the bladder microvasculature are sparse. The present study uses vascular corrosion casting and scanning electron microscopy to describe the three-dimensional anatomy of the microvasculature of the urinary bladder of the dog. Specialized features of that microvasculature, including collateral circulation, vessel folding, vessel orientation, the presence of valves and sphincters, and mucosal capillary density, that may enhance and control blood flow during normal bladder function, are described and discussed.
ORIENTAL TYRANNY IN THE EXTREME WEST: REFLECTIONS ON AMITI E ONTARIO AND LE GARE GENEROSE
Authors: POLZONETTI PIERPAOLO
Published: May 2007

This is a study of eighteenth-century operatic representations of slavery in America, focusing primarily on two Italian comic works: Ranieri de’ Calzabigi’s libretto for Amiti e Ontario (1772) and its adaptation, Le gare generose, or ‘The Contests in Generosity’ (1786), set by Giovanni Paisiello. Significant changes between the two are interpreted in relation to these works’ original cultural and political contexts, reconstructed through the examination of contemporary dramatic, journalistic and other non-fictional literature. As an operatic theme, in the late eighteenth century, slavery challenges the long established assumption of the westward migration of progress and civilization.
Triple dividends of water consumption charges in South Africa
Authors: Letsoalo Anthony , Blignaut James , de Wet Theuns , de Wit Martin , Hess Sebastiaan , Tol Richard S. J. , van Heerden Jan
Published: May 2007

The South African government is exploring ways to address water scarcity problems by introducing a water resource management charge on the quantity of water used in sectors such as irrigated agriculture, mining, and forestry. It is expected that a more efficient water allocation, lower use, and a positive impact on poverty can be achieved. This paper reports on the validity of these claims by applying a computable general equilibrium model to analyze the triple dividend of water consumption charges in South Africa: reduced water use, more rapid economic growth, and a more equal income distribution. It is shown that an appropriate budget‐neutral combination of water charges, particularly on irrigated agriculture and coal mining, and reduced indirect taxes, particularly on food, would yield triple dividends, that is, less water use, more growth, and less poverty.
Convection in Enceladus' ice shell: Conditions for initiation
Authors: Barr Amy C. , McKinnon William B.
Published: May 2007

Observations of Enceladus by the Cassini spacecraft indicate that this tiny Saturnian moon is geologically active, with plumes of water vapor and ice particles erupting from its southern polar region. This activity suggests that tidal dissipation has become spatially localized, perhaps due to a compositional, rheological, and/or thermal anomaly in its ice shell. Here we examine the role that solid‐state convection may have played in Enceladus' prolific activity by creating a suitable rheological and thermal anomaly. We find convection can only initiate in the pure water ice I shell of a differentiated Enceladus if the ice grain size is less than 0.3 mm, which is quite small, but may be realistic if non‐water‐ice impurities (and/or tidal stresses) keep grains from growing. This grain‐size restriction becomes more severe for lower basal ice temperatures, which implies that any ammonia present has not become strongly concentrated in a thin basal ocean (while convection occurs). For a maximally thick pure ice shell and underlying ocean, convective heat flows are ∼7–11 mW m−2 for ice grain sizes of 0.1–0.3 mm, compared with the ∼100 mW m−2 measured for Enceladus' south polar terrain from Cassini CIRS observations. Thus whereas solid‐state convection may be a prerequisite for Enceladus' geological activity, the observed heat flow requires strong tidal dissipation within the convecting region, and possibly, that convection reaches the surface.
Contribution of the Orbiting Carbon Observatory to the estimation of CO2 sources and sinks: Theoretical study in a variational data assimilation framework
Authors: Chevallier Frédéric , Bréon François‐Marie , Rayner Peter J.
Published: May 2007

NASA's Orbiting Carbon Observatory will monitor the atmospheric concentrations of carbon dioxide (CO2) along the satellite subtrack over the sunlit hemisphere of the Earth for more than 2 years, starting in late 2008. This paper demonstrates the application of a variational Bayesian formalism to retrieve fluxes at high spatial and temporal resolution from the satellite retrievals. We use a randomization approach to estimate the posterior error statistics of the calculated fluxes. Given our prior information about the fluxes (with error standard deviations about 0.4 g C m−2 d−1 over ocean and 4 g C m−2 d−1 over vegetated areas) and our observation characteristics (with error standard deviations about 2 ppm), we show error reductions of up to about 40% at weekly scale for a grid point of the transport model. We simulate the impact of undetected biases by perturbing the observations and show that regional biases of a few tenths of a part per million in column‐averaged CO2 can bias the inverted yearly subcontinental fluxes by a few tenths of a gigaton of carbon, which is larger than the uncertainty on the anthropogenic carbon fluxes but smaller than that of natural fluxes over most vegetated areas.
Seasonal variability of GPS‐derived zenith tropospheric delay (1994–2006) and climate implications
Authors: Jin Shuanggen , Park Jong‐Uk , Cho Jung‐Ho , Park Pil‐Ho
Published: May 2007

The total zenith tropospheric delay (ZTD) is an important parameter of the atmosphere and directly or indirectly reflects the weather and climate processes and variations. In this paper the ZTD time series with a 2‐hour resolution are derived from globally distributed 150 International GPS Service (IGS) stations (1994–2006), which are used to investigate the secular trend and seasonal variation of ZTD as well as its implications in climate. The mean secular ZTD variation trend is about 1.5 ± 0.001 mm/yr at all IGS stations. The secular variations are systematically increasing in most parts of the Northern Hemisphere and decreasing in most parts of the Southern Hemisphere. Furthermore, the ZTD trends are almost symmetrically decreasing with increasing altitude, while the summation of upward and downward trends at globally distributed GPS sites is almost zero, possibly reflecting that the secular ZTD variation is in balance at a global scale. Significant annual variations of ZTD are found over all GPS stations with the amplitude from 25 to 75 mm. The annual variation amplitudes of ZTD near oceanic coasts are generally larger than in the continental inland. Larger amplitudes of annual ZTD variation are mostly found at middle latitudes (near 20°S and 40°N) and smaller amplitudes of annual ZTD variation are located at higher latitudes (e.g., Antarctic) and the equator areas. The phase of annual ZTD variation is about 60° in the Southern Hemisphere (about February, summer) and about 240° in the Northern Hemisphere (about August, summer). The mean amplitude of semiannual ZTD variations is about 10 mm, much smaller than annual variations. The semiannual amplitudes are larger in the Northern Hemisphere than in the Southern Hemisphere, indicating that the semiannual variation amplitudes of ZTD in the Southern Hemisphere are not significant. In addition, the higher‐frequency variability (RMS of ZTD residuals) ranges from 15 to 65 mm of delay, depending on altitude of the station. Inland stations tend to have lower variability and sites at ocean and coasts have higher variability. These seasonal ZTD cycles are due mainly to the wet component variations (ZWD).
Third Radiation Transfer Model Intercomparison (RAMI) exercise: Documenting progress in canopy reflectance models
Authors: Widlowski J.‐L. , Taberner M. , Pinty B. , Bruniquel‐Pinel V. , Disney M. , Fernandes R. , Gastellu‐Etchegorry J.‐P. , Gobron N. , Kuusk A. , Lavergne T. , Leblanc S. , Lewis P. E. , Martin E. , Mõttus M. , North P. R. J. , Qin W. , Robustelli M. , Rochdi N. , Ruiloba R. , Soler C. , Thompson R. , Verhoef W. , Verstraete M. M. , Xie D.
Published: May 2007

The Radiation Transfer Model Intercomparison (RAMI) initiative benchmarks canopy reflectance models under well‐controlled experimental conditions. Launched for the first time in 1999, this triennial community exercise encourages the systematic evaluation of canopy reflectance models on a voluntary basis. The first phase of RAMI focused on documenting the spread among radiative transfer (RT) simulations over a small set of primarily 1‐D canopies. The second phase expanded the scope to include structurally complex 3‐D plant architectures with and without background topography. Here sometimes significant discrepancies were noted which effectively prevented the definition of a reliable “surrogate truth,” over heterogeneous vegetation canopies, against which other RT models could then be compared. The present paper documents the outcome of the third phase of RAMI, highlighting both the significant progress that has been made in terms of model agreement since RAMI‐2 and the capability of/need for RT models to accurately reproduce local estimates of radiative quantities under conditions that are reminiscent of in situ measurements. Our assessment of the self‐consistency and the relative and absolute performance of 3‐D Monte Carlo models in RAMI‐3 supports their usage in the generation of a “surrogate truth” for all RAMI test cases. This development then leads (1) to the presentation of the “RAMI Online Model Checker” (ROMC), an open‐access web‐based interface to evaluate RT models automatically, and (2) to a reassessment of the role, scope, and opportunities of the RAMI project in the future.
Comparison and assimilation of global soil moisture retrievals from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR‐E) and the Scanning Multichannel Microwave Radiometer (SMMR)
Authors: Reichle Rolf H. , Koster Randal D. , Liu Ping , Mahanama Sarith P. P. , Njoku Eni G. , Owe Manfred
Published: May 2007

Two data sets of satellite surface soil moisture retrievals are first compared and then assimilated into the NASA Catchment land surface model. The first satellite data set is derived from 4 years of X‐band (10.7 GHz) passive microwave brightness temperature observations by the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR‐E), and the second is from 9 years of C‐band (6.6 GHz) brightness temperature observations by the Scanning Multichannel Microwave Radiometer (SMMR). Despite the similarity in the satellite instruments, the retrieved soil moisture data exhibit very large differences in their multiyear means and temporal variability, primarily because they are computed with different retrieval algorithms. The satellite retrievals are also compared to a soil moisture product generated by the NASA Catchment land surface model when driven with surface meteorological data derived from observations. The climatologies of both satellite data sets are different from those of the model products. Prior to assimilation of the satellite retrievals into the land model, satellite‐model biases are removed by scaling the satellite retrievals into the land model's climatology through matching of the respective cumulative distribution functions. Validation against in situ data shows that for both data sets the soil moisture fields from the assimilation are superior to either satellite data or model data alone. A global analysis of the innovations (defined as the difference between the observations and the corresponding model values prior to the assimilation update) reveals how changes in model and observations error parameters may enhance filter performance in future experiments.
Simulation of brightness temperature from lunar surface and inversion of regolith‐layer thickness
Authors: Fa Wenzhe , Jin Ya‐Qiu
Published: May 2007

A correspondence of the lunar regolith‐layer thickness to the lunar digital elevation mapping is proposed to tentatively construct the global distribution of lunar regolith‐layer thickness. Using Clementine ultraviolet visible multispectral data, the global spatial distribution of FeO + TiO2 content on the lunar regolith layer is calculated. Thus the dielectric permittivity of the global lunar regolith layer can be obtained on the basis of the relationship between dielectric permittivity, bulk density, and FeO + TiO2 content. On the basis of some measurements of physical temperature of the lunar surface, an empirical formula of physical temperature distribution over the lunar surface is presented. On the basis of aforementioned works, brightness temperature of the lunar regolith layer in passive microwave remote sensing, which is planned for the Chinese Chang‐E lunar project, is numerically simulated by a three‐layer model (the layering dust, regolith, and underlying rock media) using fluctuation dissipation theorem. Taking these simulations with random noise as observations, an inversion approach of the lunar regolith‐layer thickness is developed. Because the penetration depth is small for the areas with high FeO + TiO2 content and at high‐frequency channels, for example, 19.35 GHz and 37.0 GHz in Chang‐E project, the physical temperature of the top dust layer and the regolith layer can be inverted by the brightness temperature at these high‐frequency channels using a two‐layer model. Making statistics from those points with high FeO + TiO2 content along each latitude as the reference points, the temperature variation with latitude can be retrieved. Then the regolith‐layer thickness can be inverted by brightness temperature at lower‐frequency channels, such as 1.4 GHz or 3.0 GHz. Numerical simulation and the inversion approach make an evaluation of the performance for lunar passive microwave remote sensing and for future data calibration and validation.
Hybrid fuzzy and optimal modeling for water quality evaluation
Authors: Wang Dong , Singh Vijay P. , Zhu Yuansheng
Published: May 2007

Water quality evaluation entails both randomness and fuzziness. Two hybrid models are developed, based on the principle of maximum entropy (POME) and engineering fuzzy set theory (EFST). Generalized weighted distances are defined for considering both randomness and fuzziness. The models are applied to 12 lakes and reservoirs in China, and their eutrophic level is determined. The results show that the proposed models are effective tools for generating a set of realistic and flexible optimal solutions for complicated water quality evaluation issues. In addition, the proposed models are flexible and adaptable for diagnosing the eutrophic status.
Mining‐related ground deformation in Crescent Valley, Nevada: Implications for sparse GPS networks
Authors: Gourmelen Noel , Amelung Falk , Casu Francesco , Manzo Mariarosaria , Lanari Riccardo
Published: May 2007

We use the Small BAseline Subset (SBAS) InSAR algorithm to obtain radar line‐of‐sight deformation velocities for two adjacent SAR swaths and invert the data for the 2‐D velocity field in vertical and ground range direction. The analysis reveals areas of rapid deformation caused by mining and agricultural activities in the Crescent Valley, Nevada, USA. The LOS displacements of up to 25 centimeters during the 1992–2002 period are caused by vertical and horizontal deformation. About 8 mm/yr horizontal velocity is detected 10 km from the BARGEN GPS site LEWI suggesting that the GPS station may be moving in response to the water pumping. In the Basin and Range anthropogenic ground deformation can extend several tens of kilometers from the basins into the bedrock of the Ranges.
Saturn's neutral torus versus Jupiter's plasma torus
Authors: Delamere P. A. , Bagenal F. , Dols V. , Ray L. C.
Published: May 2007

With the recent discovery of an atmospheric plume of H2O it is thought that Enceladus could deliver as much as 300 kg/s of neutral gas to Saturn's inner magnetosphere. Io is the source of roughly 1 ton/s of sulfur and oxygen gas at Jupiter. Despite the apparent similarity, the neutral/ion ratio at Saturn is 3 orders of magnitude higher than at Jupiter. We explore the flow of mass and energy at Saturn and Jupiter using a simplified homogeneous physical chemistry model to understand why these two system are so different. Our results suggest that ionization at Saturn is fundamentally limited by the slower corotational flow velocity at Enceladus, resulting in a factor of 4 lower ion pickup temperature. The net result of cooler ions at Enceladus is a cooler thermal electron population (∼2 eV) that is insufficient to generate significant ionization.
Two‐dimensional model calculations of earthquake cycle on a fluid‐infiltrated plate interface at a subduction zone: Focal depth dependence on pore pressure conditions
Authors: Mitsui Yuta , Hirahara Kazuro
Published: May 2007

We execute 2D model calculations of earthquake cycle at a subduction zone to compare two types of pore pressure models on a plate interface: hydrostatic pressure model and excess pressure model. In addition, we discuss the pore pressure fluctuations due to pore dilatation and compaction on the fluid‐infiltrated plate interface. The calculation results suggest: (1) The hydrostatic pressure model tends to produce the deeper hypocenters located around the bottom of the seismogenic zone than the excess pressure model. (2) Pore pressure fluctuations owing to pore dilatation and compaction in the deeper zone than the décollement tend to shallow a focal depth in the excess pressure model. We find that the focal depth and the recurrence interval of interplate earthquakes depend not only on the frictional parameters but also on the pore pressure conditions.