bluuebunny/crossref_metadata_2025 huggingface dataset:
Playing the game: when group success is more important than downgrading deviants
Authors: Morton Thomas A. , Postmes Tom , Jetten Jolanda
Published: September 2006

Partisan respondents evaluated a potential party leader (Study 1) or an ingroup political candidate (Study 2) who expressed normative or deviant opinions against a backdrop of public opinion that was either supportive of, or hostile toward, the ingroup's traditional beliefs (Study 1) or the normative ingroup position on a specific issue (Study 2). Across both studies, high identifiers gave stronger support to a normative candidate over a deviant candidate when public opinion was with the group, but not when public opinion was against the group. Under the latter conditions, high identifiers instead upgraded the deviant candidate. Additional analyses revealed this pattern of differential support for normative and deviant candidates among high identifiers appeared to be related to strategic considerations—specifically, the candidate's perceived chances of gaining public support and being elected. Among low identifiers, support for normative and deviant candidates was less affected by the broader context of public opinion, and was not related to such strategic considerations. These results demonstrate that responses to deviance depend on the broader context in which deviance occurs. Deviance can, at times, be a way through which groups achieve important goals. Copyright © 2006 John Wiley & Sons, Ltd.
Integrated Microanalytical System for Simultaneous Voltammetric Measurements of Free Metal Ion Concentrations in Natural Waters
Authors: Noël Stéphane , Tercier‐Waeber Mary‐Lou , Lin Lin , Buffle Jacques , Guenat Olivier , Koudelka‐Hep Milena
Published: September 2006

A complexing gel integrated microelectrode (CGIME) for direct measurements of free metal ion concentrations in natural waters has been developed. It is prepared by the successive deposition of microlayers of a chelating resin, an antifouling agarose gel and Hg on a 100‐interconnected Ir‐based microelectrode array. The trace metals of interest are in a first step accumulated on the chelating resin in proportion to their free ion concentration in solution, then released in acidic solution and detected simultaneously by using square wave anodic stripping voltammetry (SWASV). The reliability of this sensor for the simultaneous measurement of copper, lead and cadmium has been studied by a series of replicate laboratory tests. The proportionality between the voltammetric peak current intensity and the free metal ion concentrations in solution has been demonstrated by using malonate as a model ligand. Finally, the CGIME sensor was applied to the Cu and Pb free concentration measurement in sea water samples and the results compared to the free metal ion concentrations measured using hollow fiber based permeation liquid membrane (HF‐PLM) coupled to inductively coupled plasma mass spectrophotometer (ICP‐MS). Comparable concentration values were found for both metals with both techniques allowing to validate the CGIME measurements in complex media.
Fabrication of a Nanobiocomposite Film Containing Heme Proteins and Carbon Nanotubes on a Choline Modified Glassy Carbon Electrode: Direct Electrochemistry and Electrochemical Catalysis
Authors: Li Yongxin , Lin Xiangqin , Jiang Chunming
Published: September 2006

A nanocomposite electrochemical sensing film is assembled on choline (Ch) modified glassy carbon electrode (GCE), which contains multiwalled carbon nanotubes (MWNTs), Nafion cation exchanger, and myoglobin (Mb) or hemoglobin (Hb). The MWNTs provide a 3D porous and conductive network for the enzyme immobilization and Nafion acts as polymeric binder to give cast thin films. Both MWNTs and Nafion provide negative functionalities to bind to the positively charged redox proteins and to attach at the positively charged Ch modified layer, and drive the formation of homogeneous and stable nanocomposite film, the MWNT‐Nafion‐Mb. The nanocomposite film was characterized by field emission scanning electron microscope (FE‐SEM). The Mb in the nanocomposite film showed a pair of well‐defined and nearly reversible cyclic voltammetric peaks at about −0.32 V vs. SCE at pH 7.0 solution for the heme Fe(III)/Fe(II) redox couple. The immobilized heme proteins can display the features of peroxidase in electrocatalytic reductions of oxygen, hydrogen peroxide, nitric oxide, trichloroacetic acid (TCA), and bromate.
Simultaneous Detection of Peracetic Acid and Hydrogen Peroxide by Amperometry at Pt and Au Electrodes
Authors: Toniolo Rosanna , Pizzariello Andrea , Susmel Sabina , Dossi Nicolò , Bontempelli Gino
Published: September 2006

Based on preliminary voltammetric investigations at both Pt and Au electrodes in aqueous solutions buffered at different pH values in the range 0–10, two possible profitable triple‐pulse amperometric approaches were developed for determining simultaneously peroxyacetic acid (PAA) and hydrogen peroxide present in the same samples. At both surfaces a pulsed waveform applied at rotating‐disc electrodes was adopted to take advantage on one hand of the optimized signal reproducibility achieved by this potential multistep antifouling approach and on the other hand of the constant thickness of the diffusion layer, which is necessary when the recording of time‐independent currents is desired. At a rotating‐disc Pt electrode an anodic selective signal was indeed recorded for H2O2 alone, while PAA contents could be inferred only from the difference of convenient signals, since at all pHs explored its sole cathodic reaction could be observed at potentials coincident with those proper for the reduction of H2O2 too. The same pulse approach at Au electrodes instead provided totally independent signals for the two analytes considered, thus proving to be suitable for their independent detection. In fact, H2O2 alone undergoes anodic oxidation also at this surface, while the reduction of PAA occurs at potentials less cathodic than those required for H2O2. At both electrodes, the best results turned out to be achieved at pH 0 in terms of both precision (±2–4%) and detection limits (0.2–0.3 mM), as well as of linear range which extended for about three orders of magnitude. The kinetics of the equilibrium involving the generation of H2O2 from the reaction of PAA with water was also evaluated, since it was suspected of making unreliable the proposed amperometric approaches.
Government health expenditures and health outcomes
Authors: Bokhari Farasat A. S. , Gai Yunwei , Gottret Pablo
Published: September 2006

This paper provides econometric evidence linking a country's per capita government health expenditures and per capita income to two health outcomes: under‐five mortality and maternal mortality. Using instrumental variables techniques (GMM‐H2SL), we estimate the elasticity of these outcomes with respect to government health expenditures and income while treating both variables as endogenous. Consequently, our elasticity estimates are larger in magnitude than those reported in literature, which may be biased up. The elasticity of under‐five mortality with respect to government expenditures ranges from −0.25 to −0.42 with a mean value of −0.33. For maternal mortality the elasticity ranges from −0.42 to −0.52 with a mean value of −0.50. For developing countries, our results imply that while economic growth is certainly an important contributor to health outcomes, government spending on health is just as important a factor. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal drug use and the production of infant health
Authors: Noonan Kelly , Reichman Nancy E. , Corman Hope , Dave Dhaval
Published: September 2006

We estimate the effect of illicit drug use during pregnancy on two measures of poor infant health: low birth weight and abnormal infant health conditions. We use data from a national longitudinal study of urban parents that includes postpartum interviews with mothers, hospital medical record data on the mothers and their newborns, and information about the neighborhood in which the mother resides. We address the potential endogeneity of prenatal drug use. Depending on how prenatal drug use is measured, we find that it increases low birth weight by 4–6 percentage points and that it increases the likelihood of an abnormal infant health condition by 7–12 percentage points. Copyright © 2006 John Wiley & Sons, Ltd.
Campus‐based retention initiatives: Does the emperor have clothes?
Authors: Patton Lori D. , Morelon Carla , Whitehead Dawn Michele , Hossler Don
Published: September 2006

There has been very little previous evaluation research that examines the effects of interventions on persistence.
High‐pressure micro‐Raman spectroscopic study of methyltrioxorhenium(VII)
Authors: Barsan Mirela M. , Gilson Denis F. R. , Reber Christian , Butler Ian S.
Published: September 2006

Micro‐Raman spectra of methyltrioxorhenium(VII), CH3ReO3, were recorded at high external pressures, up to about 41 kbar, with the aid of a diamond‐anvil cell (DAC) in the presence and absence of paraffin oil (Nujol) as a pressure‐transmitting medium. The wavenumber vs external pressure plots display linear behavior up to 41 kbar, at which point sample decomposition occurs. In the case of the modes associated with the methyl group, the CH antisymmetric stretching modes are more sensitive to pressure (dν/dP = 0.88 and 1.04 cm−1 kbar−1) than the symmetric mode (dν/dP = 0.63 cm−1 kbar−1), and one branch of the split degenerate CH rocking mode exhibits a negative pressure dependence (−0.15 cm−1 kbar−1). The degeneracies of the ReO3 rocking and antisymmetric bending modes, located at 239 and 325 cm−1, respectively, at ambient pressure, are lifted in the crystal, and the resulting splitting increases as the pressure increases. The Re–C stretching vibration and one branch of the split degenerate ReO3 rocking modes are both particularly sensitive to pressure (dν/dP ≈ 0.96 cm−1 kbar−1). The dν/dP values for the ν(ReO) modes are significantly lower than those reported for other oxorhenium compounds. Copyright © 2006 John Wiley & Sons, Ltd.
Raman, FT‐IR, and DFT studies of 3,5‐pyrazoledicarboxylic acid and its Ce(III) and Nd(III) complexes
Authors: Kostova Irena , Peica Niculina , Kiefer Wolfgang
Published: September 2006

3,5‐Pyrazoledicarboxylic acid was used as a ligand for the synthesis of its Ce(III) and Nd(III) complexes. The complexes of Ce(III) and Nd(III) with 3,5‐pyrazoledicarboxylic acid were synthesized and their compositions were determined by elemental analysis. Vibrational study in the solid state of 3,5‐pyrazoledicarboxylic acid and its new Ce(III) and Nd(III) complexes was performed by IR and Raman spectroscopy. The changes observed between the IR and Raman spectra of the ligand and of the complexes allowed us to establish the coordination mode of the metal in both complexes. The comparative vibrational analysis of the free ligand and its lanthanide(III) complexes gave evidence that 3,5‐pyrazoledicarboxylic acid binds Ln(III) through the deprotonated carboxylic oxygens. The density functional theory (DFT) calculated geometries, harmonic vibrational modes and Raman scattering activities of the ligand were in good agreement with the experimental data, and a complete vibrational assignment is being proposed. The experimental IR and Raman bands of the ligand were assigned to normal modes on the basis of DFT calculations. The effect of the intramolecular hydrogen bonds in the ligand on vibrational mode positions is also discussed. The characteristic IR and Raman bands of 3,5‐pyrazoledicarboxylic acid and its lanthanide complexes were specified and discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Characterisation of inorganic pigments in ancient glass beads by means of Raman microspectroscopy, microprobe analysis and X‐ray diffractometry
Authors: Welter N. , Schüssler U. , Kiefer W.
Published: September 2006

Ancient coloured glass beads from Sri Lanka and Oman were analysed by Raman microspectroscopy for non‐destructive identification of inorganic pigments in the glass. Calcium phosphate (Ca3(PO4)2), cassiterite (SnO2), cuprite (Cu2O) and a Pb(Sn,Si)O3‐type lead tin oxide were found to be used as colouring agents. Moreover, a distinction between lead‐based and alkali‐based glass matrices could be made. Electron microprobe analysis and X‐ray diffractometry were performed to show the capability of Raman microspectroscopy in comparison to these methods for answering archaeometric questions. Copyright © 2006 John Wiley & Sons, Ltd.
Experiments of a diode-pumped Nd:GdVO4/LT-GaAs
Q-switched and mode-locked laser
Authors: Yang J , Fu Q , Liu J , Wang Y
Published: September 2006

A diode-pumped passively Q-switched mode-locked (QML)
Nd:GdVO4 laser with a low temperature GaAs (LT-GaAs) saturable
absorber is presented. The maximal Q-switched mode-locked average
output power was 798 mW with the Q-switched envelop having a
repetition rate of 125 kHz. The mode-locked pulse trains inside
the Q-switched pulse envelope had a repetition rate of ∼
750 MHz. The laser properties of the operational parameters on
the pump power were also investigated experimentally.
Single Center Experience of 39 Patients With Preoperative Portal Vein Thrombosis Among 404 Adult Living Donor Liver Transplantations
Authors: Egawa Hiroto , Tanaka Koichi , Kasahara Mureo , Takada Yasutsugu , Oike Fumitaka , Ogawa Kohei , Sakamoto Seisuke , Kozaki Koichi , Taira Kaoru , Ito Takashi
Published: September 2006

Living donor liver transplantation (LDLT) for patients with portal vein thrombosis (PVT) involves technical difficulty. The aim of this research was to analyze their preoperative diagnosis of PVT, operative procedures, and postoperative courses of patients with preoperative PVT. Thirty-nine patients of 404 adult patients (9.7%) undergoing LDLT in our hospital from 1996 June to 2004 December had PVT at their transplantation. Twenty-nine patients had intractable ascites, 21 had gastrointestinal bleeding, and 18 had encephalopathy. The thrombus was located in the portal trunk in 23, in the portal trunk and superior mesenteric vein (SMV) in 7, and developed into the SMV and the splenic vein in 8. The occlusive grade was partial in 29, and complete in 10 patients. The thrombus was removed by a simple technique, and eversion and/or incision technique, or total removal of the portal vein (PV). The PV was reconstructed with the thrombectomized native PV, with an interposed vein graft, or porto-caval hemitransposition. Advanced PVT had a significant impact on blood loss and hospital mortality. Three out of 10 patients with residual PVT required radiological and/or surgical intervention after transplantation. In conclusion, thorough planning is essential for a successful LDLT outcome for patients with preexisting PVT.
Liver Transpl 12:1512–1518, 2006.

© 2006 AASLD.
12-Month Follow-Up Analysis of A Multicenter, Randomized, Prospective Trial in De Novo Liver Transplant Recipients (Lis2t) Comparing Cyclosporine Microemulsion (C2 Monitoring) and Tacrolimus
Authors: Levy Gary , Grazi Gian Luca , Sanjuan Fernando , Wu Youmin , Mühlbacher Ferdinand , Samuel Didier , Friman Styrbjorn , Jones Robert , Cantisani Guido , Villamil Federico , Cillo Umberto , Clavien Pierre Alain , Klintmalm Goran , Otto Gerd , Pollard Stephen , McCormick Aiden P
Published: September 2006

The LIS2T study was an open-label, multicenter study in which recipients of a primary liver transplant were randomized to cyclosporine microemulsion (CsA-ME) (Neoral) (n = 250) (monitoring of blood concentration at 2 hours postdose) C2 or tacrolimus (n = 245) (monitoring of trough drug blood level [predose]) C0 to compare efficacy and safety at 3 and 6 months and to evaluate patient status at 12 months. All patients received steroids with or without azathioprine. At 12 months, 85% of CsA-ME patients and 86% of tacrolimus patients survived with a functioning graft (P not significant). Efficacy was similar in deceased- and living-donor recipients. Significantly fewer hepatitis C–positive patients died or lost their graft by 12 months with CsA-ME (5/88, 6%) than with tacrolimus (14/85, 16%) (P < 0.03). Recurrence of hepatitis C virus in liver grafts was similar in each group. Based on biopsies driven by clinical events, the mean time to histological diagnosis of hepatitis C virus recurrence was significantly longer with CsA-ME (100 ± 50 days) than with tacrolimus (70 ± 40 days) (P < 0.05). Median serum creatinine at 12 months was 106 μmol/L with CsA-ME and with tacrolimus. More patients who were nondiabetic at baseline received antihyperglycemic therapy in the tacrolimus group at 12 months (13% vs. 5%, P < 0.01). Of patients who were diabetic at baseline, more tacrolimus-treated individuals required anti-diabetic treatment at 12 months (70% vs. 49%, P = 0.02). Treatment for de novo or preexisting hypertension or hyperlipidemia was similar in both groups. In conclusion, the efficacy of CsA-ME monitored by blood concentration at 2 hours postdose and tacrolimus in liver transplant patients is equivalent to 12 months, and renal function is similar. More patients required antidiabetic therapy with tacrolimus regardless of diabetic status at baseline.
Liver Transpl 12:1464–1472, 2006.

© 2006 AASLD.
Transjugular Intrahepatic Portosystemic Shunt for Treatment of Intractable Colonic Ischemia Associated With Portal Hypertension: A Bridge To Liver Transplantation
Authors: Schneider Jonathan A. , White Edward A. , Welch Derek C. , Stokes LeAnn S. , Raiford David S.
Published: September 2006

A 64-year-old man with portal hypertension secondary to hepatic nodular transformation was awaiting liver transplantation when he presented with severe, unrelenting abdominal pain, fever, and hypotension. Computed tomographyrevealed pneumatosis within the cecum and ascending colon. Because of his advanced liver disease and the perceived high likelihood of a poor outcome after colonic resection, he was managed medically. He improved initially but had a lengthy hospital course notable for intractable intestinal ischemia and gastrointestinal bleeding. Magnetic resonance angiography demonstrated patent mesenteric, portal, and hepatic vessels. His blood pressure was typically 90/55 mm Hg (mean arterial pressure, 65-70 mm Hg) despite intravenous fluids and blood product replacement. The hypothesis developed that the patient's level of portal hypertension was sufficiently severe (in the face of his low mean systemic arterial pressure) to compromise perfusion of the colonic mucosa. Were this hypothesis correct, then portal decompression might enhance the blood pressure gradient across the bowel and improve mucosal perfusion. With this in mind, a transjugular intrahepatic portosystemic shunt (TIPS) was placed. There was reduction of the portal vein to inferior vena cava gradient from 29 mm Hg to 9 mm Hg and his abdominal pain and gastrointestinal bleeding ceased. His prompt and sustained improvement following TIPS shunt placement is consistent with the hypothesis that high portal pressure was flow limiting, thus contributing to persisting intestinal ischemia. This case represents the first report of use of a TIPS shunt to address colonic ischemia associated with portal hypertension.
Liver Transpl 12: 1540–1543, 2006.

© 2006 AASLD.
Donor Quality of Life Before and After Adult-To-Adult Right Liver Live Donor Liver Transplantation
Authors: Chan See Ching , Liu Chi Leung , Lo Chung Mau , Lam Banny K. , Lee Evelyn W. , Fan Sheung Tat
Published: September 2006

Donor right hepatectomy for adult-to-adult live donor liver transplantation (ALDLT) is a major surgical operation for the benefit of the recipient. Justification of procedure mandates knowledge of the possible physical and psychological negative effects on the donor. We prospectively and longitudinally quantified donor quality of life using generic and condition-specific questionnaires up to 1 year. The generic questionnaires were the Karnofsky Performance Status scale and the Chinese (Hong Kong) version of the Medical Outcomes Study 36-Item Short-Form Survey, which measures 8 health concepts: 4 physical components and 4 mental components. Within 1 year, 30 consecutive donors were included. These 11 male and 19 female donors (36.7% and 63.3%, respectively) had a median age of 35 years (range, 21-56 years). There was no donor mortality or major complications. Donor quality-of-life worsening was most significant in the first 3 postoperative months, particularly among the physical components. The physical and mental components returned to the previous levels in 6 to 12 months' time, though the Karnofsky performance scores were slightly lower at 1 year (P = 0.011). Twenty-six (86.7%) donors declared that they would donate again if there were such a need and it were technically possible. It was noticed that older donors were more likely to express unwillingness to donate again. In conclusion, the temporary worsening of donor quality of life substantiates ALDLT as an acceptable treatment modality.
Liver Transpl 12:1529–1536, 2006.

© 2006 AASLD.
the Influence of Ctla-4 Gene Polymorphisms on Liver Transplant Outcomes
Authors: Perkins James D.
Published: September 2006

Abstract

Background:

The cytotoxic T lymphocyte antigen 4 (CTLA-4) gene encodes for a membrane bound (mCTLA-4) and a soluble sCTLA-4 isoform, which are both involved in regulation of T cell function. The CTLA-4 +49A/G single nucleotide polymorphism (SNP) influences expression of mCTLA-4; +6230G/A SNP affects the production of soluble sCTLA-4.

Aim:

To examine whether these functional SNPs influence the rate of rejection after liver transplantation.

Patients and methods:

Liver graft recipients (n = 483) were genotyped for both SNPs, and haplotypes were reconstructed. Association with rejection was tested by the log rank test using the Kaplan-Meier method with time to the first acute rejection episode as outcome. Multiple analysis of SNPs together with demographic factors was performed by Cox regression.

Results:

Three haplotypes were observed in the cohort: +49A/+6230A, +49A/+6230G, and +49G/+6230G. The +49A/+6230G haplotype was significantly and dose dependently associated with acute rejection (p = 0.01). Of the demographic factors tested, only underlying liver disease was significantly associated with rejection. Adjusted for underlying liver disease, each additional +49A/+6230G haplotype allele resulted in a significantly higher risk of acute rejection (risk ratio 1.34 (95% confidence interval 1.04-1.72); p = 0.02). Patients who lacked this haplotype had the lowest, carriers an intermediate, and homozygotes the highest risk of acute rejection.

Conclusion:

The CTLA-4 +49A/+6230G haplotype, which encodes for normal mCTLA-4 expression but reduced sCTLA-4 production, is a co-dominant risk allele for acute rejection after clinical liver transplantation. This implies that even under immunosuppression, CTLA-4 is critically involved in the regulation of the human immune response to allogeneic grafts.
Synthesis and structure elucidation of five series of aminoflavones using 1D and 2D NMR spectroscopy
Authors: Barros Ana I. R. N. A. , Silva Artur M. S.
Published: September 2006

Twenty‐six new aminoflavones have been synthesised by two different methods and the structure elucidation was accomplished using extensive 1D (1H,13C) and 2D NMR spectroscopic studies (COSY, HSQC and HMBC experiments). Copyright © 2006 John Wiley & Sons, Ltd.
Structural determination of saponins from Hedysarum polybotrys
Authors: Liu Yi , Zhang Qingying , Chen Hubiao , Wang Bin , An Dongge , Zhao Yuying
Published: September 2006

Four saponins (1–4) were isolated from the roots of Hedysarum polybotrys Hand.‐Mazz. and obtained from Hedysarum (Tourn.) L for the first time. Their structures were identified on the basis of spectroscopic data. MS, 1D and 2D NMR including HMQC, HMBC, 1H–1H COSY and NOESY permitted correct assignments of all 1H and 13C signals of 1 and 2, and the 13C NMR data of 2 were reported for the first time. Copyright © 2006 John Wiley & Sons, Ltd.
A program for the visualisation, extraction, and reporting of NMR data from plate chemistry samples
Authors: Bernstein Michael A. , Stoddart Simon
Published: September 2006

We describe a program for the viewing, analysis, and reporting of 1D NMR spectra. The program provides an intuitive environment to display 1D NMR spectra, and assists with data reduction and reporting. It is particularly well suited for multiple NMR spectra derived from the recording of spectra of samples in microtitre plates, where it adopts a unique, effective, and user‐friendly approach. This also allows for quick overviews of the underlying NMR data and offers an effective tool for quality control in parallel chemistry. Copyright © 2006 John Wiley & Sons, Ltd.
Discrete crack modelling in a new X‐FEM format with emphasis on dynamic response
Authors: Svahn Per‐Ola , Ekevid Torbjörn , Runesson Kenneth
Published: September 2006

The displacement field in quasi‐brittle material is localized into narrow fracture zones during the process of decohesion. The numerical modelling of the physically propagating displacement discontinuities is considered to be inherently difficult. In this paper, the introduction of continuous discontinuities into the finite element formulation is based on the extended finite element method (X‐FEM). This paper extends the theory by further incorporating arbitrary discontinuities in the approximation and presenting numerical procedures to handle several fields of discontinuities. The discontinuous approximation is accomplished by usage of basis functions of very limited support; only non‐zero in the elements containing the crack. Moreover, the introduction of discontinuities in a continuum is discussed and a robust numerical procedure is proposed. Further, the mechanical behaviour of cracks in a quasi‐brittle material largely governs the overall mechanical response of the material, and the implementation of a cohesive crack model based on anisotropic damage coupled to plasticity is emphasized. Numerical examples for both static and dynamic, transient, loading show that the proposed X‐FEM format in combination with the cohesive crack model has a good performance and leads to an efficient implementation. Finally, the proposed forward method for propagation of cracks and introduction of new ones is robust and stable. Copyright © 2006 John Wiley & Sons, Ltd.
Distance bound for nonconvex polyhedral models in close proximity
Authors: Jiménez P. , Torras C.
Published: September 2006

In many applications, it suffices to know a lower bound on the distance between objects, instead of the exact distance itself, which may be more difficult to compute. Such an easy‐to‐compute lower bound on the distance between two nonconvex polyhedra is presented here, which does not require a decomposition of the original polyhedra into convex entities. Furthermore, a suitable preprocessing of the polyhedra permits lowering the effort needed to compute this lower bound, and improves its quality. Experimental evidence is presented of the promise of this approach for assembly applications. © 2006 Wiley Periodicals, Inc.
Profiles of random trees: Plane‐oriented recursive trees
Authors: Hwang Hsien‐Kuei
Published: September 2006

We derive several limit results for the profile of random plane‐oriented recursive trees. These include the limit distribution of the normalized profile, asymptotic bimodality of the variance, asymptotic approximation to the expected width, and the correlation coefficients of two level sizes. Most of our proofs are based on a method of moments. We also discover an unexpected connection between the profile of plane‐oriented recursive trees (with logarithmic height) and that of random binary trees (with height proportional to the square root of tree size). © 2006 Wiley Periodicals, Inc. Random Struct. Alg., 2007
A sustainable product needing a sustainable procurement commitment: the case of green waste in Wales
Authors: Dawson G. F. , Probert E. J.
Published: September 2006

European waste legislation aims to reduce the amount and type of waste that is sent to landfill. Hence member states are investigating alternatives, and trying to treat waste as a resource. In the UK there is a focus on producing compost from biodegradable waste. This emphasis is particularly strong in Wales, where strategy encourages the collection and composting of green garden waste.

A survey has been conducted within the composting industry in Wales to determine the barriers that need to be overcome in order for green waste compost to become an accepted and viable product. The research investigates purchasing preferences, and identifies the important role of specifications in purchasing decisions.

Welsh policy initiatives support the concept of sustainable development and encourage sustainable procurement. However, practical actions are required to turn these policies into practice. This study suggests how sustainable procurement initiatives could be used to facilitate the inclusion of green waste compost in contract specifications and hence enable public bodies to close the recycling loop. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
An incomplex algorithm for fast suffix array construction
Authors: Schürmann Klaus‐Bernd , Stoye Jens
Published: September 2006

The suffix array of a string is a permutation of all starting positions of the string's suffixes that are lexicographically sorted. We present a practical algorithm for suffix array construction that consists of two easy‐to‐implement components. First it sorts the suffixes with respect to a fixed length prefix; then it refines each bucket of suffixes sharing the same prefix using the order of already sorted suffixes. Other suffix array construction algorithms follow more complex strategies. Moreover, we achieve a very fast construction for common strings as well as for worst case strings by enhancing our algorithm with further techniques. Copyright © 2006 John Wiley & Sons, Ltd.
The impact of Supplemental Instruction on teaching students how to learn
Authors: McGuire Saundra Yancy
Published: September 2006

This chapter presents information on the transformation of higher education, the learning theories on which the Supplemental Instruction (SI) model is based, and the characteristics of today's student population, and concludes with a look at the benefits and challenges of implementing SI in the twenty‐first century.
Maternal hemodynamic changes following treatment by laser coagulation of placental vascular anastomoses and amnioreduction in twin‐to‐twin transfusion syndrome
Authors: Nizard J. , Gussi I. , Ville Y.
Published: September 2006

Objectives

To investigate maternal hemodynamic changes following laser therapy and amnioreduction in twin‐to‐twin transfusion syndrome (TTTS).

Methods

Thirty‐nine cases with severe TTTS were treated at 16–26 weeks of gestation. Maternal hemodynamic evaluation was performed, including heart rate (HR), arterial pressure and echocardiography with calculation of shortening fraction (SF), left atrial dimensions, stroke volume (SV), cardiac output (CO) and total vascular resistance (TVR), before and 6 h and 24 h after placental surgery. Hemoglobin (Hb), hematocrit (Ht) and protein levels were also measured. Cases were retrospectively divided into groups according to treatment: Group A had laser therapy followed by amnioreduction >1000 mL (n = 25); Group B had laser therapy followed by amnioreduction <1000 mL (n = 14).

Results

The mean gestational age at inclusion was 21 (range, 16–26) weeks. The mean amniotic fluid withdrawal was 1700 (range, 1000–3000) and 300 (range, 150–800) mL in Groups A and B, respectively. Cases in Group A showed a decrease in mean arterial blood pressure (P = 0.011) and in TVR (P < 0.0001) and an increase in CO (P = 0.008) and SV (P = 0.022). There was no difference in HR. Significant hemodilution developed as early as 6 h after the procedure, with a reduction in Ht (P < 0.0001), plasma protein (P < 0.0001) and Hb levels of 1.2 g/dL on average (P < 0.0001). There were no changes in any parameters in Group B.

Conclusions

Amnioreduction of severe polyhydramnios in TTTS induces maternal hemodynamic changes within the first 6 h that persist at least 24 h after treatment. These adaptative changes are compatible with hemodilution. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Ein‐Blick in die Nano‐Elektronik: Bausteine, Funktionsprinzipien und virtuelle Reisen
Authors: Gleiche Michael , Haumann Carola , Baron Waldemar , Dreßen Jochen
Published: September 2006

Die Elektronik erobert wie keine andere Technologie mit rasanter Geschwindigkeit den Nanokosmos. Basis für moderne, hochkomplexe Produkte sind nur ein wenig (Quarz‐)Sand und einige metallische Zugaben, wie das aktuelle, vom Bundesministerium für Bildung und Forschung (BMBF) initiierte Exponat „Vom Sand zum Superchip”︁ zeigt. Der gesamte Weg der Wertschöpfung in der Halbleiterindustrie wird anschaulich vermittelt. Bereits heute liegt die Größe funktionskritischer Bauteile der Chips im Nanometerbereich und an manchen Stellen sogar in der Größenordnung von nur wenigen Atomlagen. Die Herausforderungen an die Chiphersteller werden dabei immer größer. Es gilt, neue Materialien zu entwickeln und immer aufwendigere Prozesse zu kontrollieren. Deutschland hat sich als weltweit führender Forschungs‐ und Fertigungsstandort für Nanoelektronik etabliert. Als Grundlage dafür wurden nicht nur die Ansiedlung von Produktionsstätten der Siliziumelektronik, wie AMD und Infineon/Qimonda in Dresden, gefördert, sondern auch Kompetenzen gezielt gebündelt. Dazu gehört z. B. die Erforschung und Herstellung von Photolithographiemasken (AMTC1) und nanoelektronischen Bauelementen (Fraunhofer CNT2) in Dresden sowie die Gründung des edacentrums3 (Automatisierung des Chipentwurfes) in Hannover. Einen tiefen Einblick in die Welt der Nanoelektronik gewähren darüber hinaus auf spielerische Weise die sog. „Nanoreisen”︁, entwickelt im Auftrag des BMBF und adressiert an Öffentlichkeit und interessierten Nachwuchs.
Untersuchung dünner Schichten mittels Röntgenreflektometrie
Authors: Dietsch Reiner , Holz Thomas
Published: September 2006

Geometrische Parameter wie Quellgröße und Blendengrößen, Abstände zwischen den einzelnen röntgenoptischen Komponenten und die charakteristischen Kenngrößen der strahlformenden Elemente beeinflussen die Winkel‐ und Energieauflösung in der experimentellen Anordnung der Röntgenreflektometrie.

In Multischicht‐Röntgenoptiken und Kristallmonochromatoren erfolgt die Kollimation und die Monochromatisierung entsprechend der BRAGG’schen Gleichung.

Kristalle bestehen aus einem 3‐dim. Gitter, in dem die streuenden Netzebenenen regelmäßig angeordnet sind. Die Zahl der kohärent streuenden Netzebenen ist sehr hoch. Deshalb sind Energie‐ und Winkelauflösung eines Kristallmonochromators um ca. eine Größenordnung höher als beim Multischichtsystem, welches als 1‐dim. periodisches Gitter verstanden werden kann.

Typisch für eine Multischicht‐Röntgenoptik ist eine Energieauflösung im Bereich ΔE/E = Δλ/λ von 10‐1 bis 10‐2. Demzufolge ist die Winkeldivergenz in der Größenordnung zwischen 0.01° und 0.1° z. B. für Cu Kα Strahlung.

Allein mit Multischichtröntgenoptiken können Gesamtschichtdicken bis d = 270nm an Hand der Dickenoszillationen im Reflektogramm aufgelöst werden. Oberhalb dieser Gesamtschichtdicke ist es erforderlich, die Winkeldivergenz durch Strahleinkopplung in einen Kristallmonochromator (CC) zu reduzieren und damit den auflösbaren Dickenbereich zu erhöhen.

Der Gewinn an Auflösung durch Kopplung einer Multischichtoptik und eines CC konnte am Beispiel einer 400nm Multischicht gezeigt werden.
Phenological responses of plants to climate change in an urban environment
Authors: Luo Zhongkui , Sun Osbert J. , Ge Quansheng , Xu Wenting , Zheng Jingyun
Published: September 2006

Global climate change is likely to alter the phenological patterns of plants due to the controlling effects of climate on plant ontogeny, especially in an urbanized environment. We studied relationships between various phenophases (i.e., seasonal biological events) and interannual variations of air temperature in three woody plant species (Prunus davidiana,Hibiscus syriacus, andCercis chinensis) in the Beijing Metropolis, China, based on phenological data for the period 1962–2004 and meteorological data for the period 1951–2004. Analysis of phenology and climate data indicated significant changes in spring and autumn phenophases and temperatures. Changes in phenophases were observed for all the three species, consistent with patterns of rising air temperatures in the Beijing Metropolis. The changing phenology in the three plant species was reflected mainly as advances of the spring phenophases and delays in the autumn phenophases, but with strong variations among species and phenophases in response to different temperature indices. Most phenophases (both spring and autumn phenophases) had significant relationships with temperatures of the preceding months. There existed large inter‐ and intra‐specific variations, however, in the responses of phenology to climate change. It is clear that the urban heat island effect from 1978 onwards is a dominant cause of the observed phenological changes. Differences in phenological responses to climate change may cause uncertain ecological consequences, with implications for ecosystem stability and function in urban environments.
Unbound states in quantum heterostructures
Authors: Ferreira R. , Bastard G.
Published: September 2006

We report in this review on the electronic continuum states of semiconductor Quantum Wells and Quantum Dots and highlight the decisive part played by the virtual bound states in the optical properties of these structures. The two particles continuum states of Quantum Dots control the decoherence of the excited electron – hole states. The part played by Auger scattering in Quantum Dots is also discussed.
Traveling wave solutions of the heat flow of director fields
Authors: Bertsch M. , Primi I.
Published: September 2006

We consider the simplest possible heat equation for director fields,

u_{t} = \mathrm{\Delta }u + |\mathrm{∇}u|^{2}u

(

|u| = 1

), and construct axially symmetric traveling wave solutions defined in an infinitely long cylinder. The traveling waves have a point singularity of topological degree

0

or

1

.

Dans ce papier nous considérons l'équation de la chaleur la plus simple pour champs de vecteurs unitaires,

u_{t} = \mathrm{\Delta }u + |\mathrm{∇}u|^{2}u

(

|u| = 1

), avec domaine donné par un cylindre infiniment long. Pour cette équation nous édifions des solutions axialement symétriques en forme de front progressif. Ces fronts progressifs ont un point de singularité avec degré topologique

0

ou

1

.
Distance learning of foreign languages
Authors: White Cynthia
Published: September 2006

This article provides a critical overview of the field of distance language learning, challenging the way in which the field is often narrowly conceptualised as the development of technology-mediated language learning opportunities. Early sections focus on issues of concept and definition and both theoretical and pedagogical perspectives on the field. Emphasis is placed on evident shifts from a concern with structural and organisational issues to a focus on transactional issues associated with teaching/learning opportunities within emerging paradigms for distance language learning. The next section reviews choices and challenges in incorporating technology into distance language learning environments, foregrounding decisions about technology made in particular sociocultural contexts, the contribution of ‘low-end’ technologies and research directions in developing new learning spaces and in using online technologies. The investigation of learner contributions to distance language learning is an important avenue of enquiry in the field, given the preoccupation with technology and virtual learning environments, and this is the subject of section six. The two final sections identify future research directions and provide a series of conclusions about research and practice in distance language learning as technology-mediated interactions increasingly come to influence the way we think about the processes of language learning and teaching.
Understanding the dynamics of Ebola epidemics
Authors: LEGRAND J. , GRAIS R. F. , BOELLE P. Y. , VALLERON A. J. , FLAHAULT A.
Published: September 2006

Ebola is a highly lethal virus, which has caused at least 14 confirmed outbreaks in Africa between 1976 and 2006. Using data from two epidemics [in Democratic Republic of Congo (DRC) in 1995 and in Uganda in 2000], we built a mathematical model for the spread of Ebola haemorrhagic fever epidemics taking into account transmission in different epidemiological settings. We estimated the basic reproduction number (R0) to be 2·7 (95% CI 1·9–2·8) for the 1995 epidemic in DRC, and 2·7 (95% CI 2·5–4·1) for the 2000 epidemic in Uganda. For each epidemic, we quantified transmission in different settings (illness in the community, hospitalization, and traditional burial) and simulated various epidemic scenarios to explore the impact of control interventions on a potential epidemic. A key parameter was the rapid institution of control measures. For both epidemic profiles identified, increasing hospitalization rate reduced the predicted epidemic size.
Analysis of clonal relationship amongShigella sonneiisolates circulating in Argentina
Authors: PICHEL M. , GONZÁLEZ FRAGA S. , TERRAGNO R. , MULKI J. , GENTILE A. , KREMER C. , MOLA A. M. , NOSEDA R. , BINSZTEIN N.
Published: September 2006

Thirty-five isolates ofShigella sonneifrom patients with diarrhoea in three geographic regions of Argentina were examined for genetic diversity by pulsed-field gel electrophoresis (PFGE) and plasmid profile. PFGE ofXbaI andBlnI DNA digests confirmed the occurrence of outbreaks in two regions caused by two separate predominant clones ofS. sonnei. The third region was characterized by three circulating clones, one of which was possibly associated with an outbreak. Similar plasmids were found in distinct clones and in one outbreak clone five different plasmid profiles were identified. Antimicrobial resistance of the isolates varied from fully susceptible to the agents tested, to resistance to cotrimoxazole, ampicillin and ciprofloxacin. Antibiotic resistance did not correlate with plasmid content. This information will form the basis for active surveillance of shigellosis in Argentina and elsewhere in the region through the PulseNet International Network.
Rapidly moving sources of upper band ELF/VLF chorus near the magnetic equator
Authors: Platino M. , Inan U. S. , Bell T. F. , Pickett J. S. , Canu P.
Published: September 2006

Multiple simultaneous wideband (Gurnett et al., 2001) measurements on the Cluster spacecraft of upper band chorus emissions near the magnetic equator (at magnetic latitudes between −20° and 10° and L shells ranging between L = 4 and L = 5) are used to deduce the properties of the compact source regions of ELF/VLF chorus emissions. The frequency differences exhibited by the same chorus emissions observed on different spacecraft are interpreted (Inan et al., 2004) in terms of a differential Doppler shift, using a simple model involving rapidly moving sources traveling at speeds comparable to the parallel resonant velocity of counter‐streaming gyroresonant electrons. Cluster observations are used to determine the location and extent along the Earth's magnetic field lines of the source of chorus. Frequency and time differences between spacecraft are interpreted as a direct consequence of the rapid motion of highly localized source regions of chorus. In this paper, we examine the previously presented model of rapid motion of sources of chorus, extending the calculations to a three‐dimensional space, using measurements of the four Cluster spacecraft. These calculations of source location and velocity as a function of frequency indicate that chorus sources move a distance of ∼6000 km along the field lines. The emitted chorus waves at the source are assumed to have a wide range of wave normal angles, but the rays reaching the spacecraft seem to be the ones with lower angles (with some exceptions). The ranges of velocity obtained vary with frequency around values ranging from ∼0.01c to ∼0.04c.
Numerical simulation of the LAGEOS thermal behavior and thermal accelerations
Authors: Andrés J. I. , Noomen R. , Vecellio None S.
Published: September 2006

The temperature distribution throughout the LAGEOS satellites is simulated numerically with the objective to determine the resulting thermal force. The different elements and materials comprising the spacecraft, with their energy transfer, have been modeled with unprecedented detail. The radiation inputs on the satellites are direct solar (eclipse modulated), Earth albedo, and Earth infrared radiations. For each satellite the lifetime temperature (behavior) of 2133 nodes is computed. On the basis of this distribution, individual forces and the net instantaneous accelerations are obtained. Simulations yield typical temperature variations ranging between 30 and 100 K for different elements and materials, whereas the net instantaneous accelerations are on the order of 70 pm s−2, in good agreement with previous results. Simulations also show the importance of the consideration of a proper orientation of the satellite: LOSSAM yields acceleration differences of up to three times the acceleration obtained with a constant spin axis orientation. The temperature of the four germanium retroreflectors deviates up to 70 and 100 K with respect to their silica counterparts for LAGEOS I and II, respectively. This generates thermal acceleration differences of several pm s−2, up to 25% of the postulated difference in reflectivity between hemispheres. Two factors play a major role: the spin rate and the Sun aspect angle with respect to the spin axis. On the basis of the latter, two characteristic periods can be distinguished: a rapid spin, slow drift period (until 13 and 8 years after launch for LAGEOS I and II, respectively) and a slow spin, rapid wobbling afterward. The acceleration results will be used in a refined orbit computation in a subsequent investigation.
Three‐dimensional finite difference time domain modeling of the Schumann resonance parameters on Titan, Venus, and Mars
Authors: Yang Heng , Pasko Victor P. , Yair Yoav
Published: September 2006

The conducting ionosphere and conducting surface of Titan, Venus, and Mars form a concentric resonator, which would support the possibility of the existence of global electromagnetic resonances. On Earth, such resonances are commonly referred to as Schumann resonances and are excited by lightning discharges. The detection of such resonances on other planets would give a support for the existence of the electrical discharges in the lower atmosphere on these planets. In this paper, a three‐dimensional finite difference time domain modeling for the extremely low frequency propagation is employed to study the Schumann resonance problems on Titan, Venus, and Mars. The atmospheric conductivity profiles for these studies are derived from the previously reported ionospheric models for these planets. The Schumann resonance frequencies and Q factors on these planets are calculated and are critically compared with those obtained from the previously published models.