bluuebunny/crossref_metadata_2025 huggingface dataset:
Ferritin iron minerals are chelator targets, antioxidants, and coated, dietary iron
Authors: Theil Elizabeth C.
Published: August 2010

Cellular ferritin is central for iron balance during transfusions therapies; serum ferritin is a small fraction of body ferritin, albeit a convenient reporter. Iron overload induces extra ferritin protein synthesis but the protein is overfilled with the extra iron that damages ferritin, with conversion to toxic hemosiderin. Three new approaches that manipulate ferritin to address excess iron, hemosiderin, and associated oxidative damage in Cooley's Anemia and other iron overload conditions are faster removal of ferritin iron with chelators guided to ferritin gated pores by peptides; more ferritin protein synthesis using ferritin mRNA activators, by metal complexes that target mRNA 3D structures; and determining if endocytotic absorption of iron from legumes, which is mostly ferritin, is regulated during iron overload to prevent excess iron entry while providing protein. More of a focus on ferritin features, including protein cage structure, iron mineral, regulatable mRNA, and specific gut absorption properties, will achieve the three novel experimental goals for managing iron homeostasis with transfusion therapies.
Hematopoietic stem cell mobilization strategies for gene therapy of beta thalassemia and sickle cell disease
Authors: Yannaki Evangelia , Stamatoyannopoulos George
Published: August 2010

Effective gene therapy for hemoglobinopathies will require high numbers of autologous gene‐engineered hematopoetic stem cells to be reintroduced into the patients. Stem cell mobilization using G‐CSF is the most convenient and effective approach to achieve this goal, but it can have severe side effects in sickle cell anemia and be potentially harmful in the case of severe thalassemia. Hence, the optimal way of collection of hematopoetic stem cells from patients with thalassemia and sickle cell disease needs to be determined. In this paper, we review the possible risks of G‐CSF mobilization in hemoglobinopathies and we outline the approaches used in an on‐going clinical trial in which pretreatment with hydroxyurea is used to reduce potential risks of G‐CSF administration to patients with severe beta thalassemia.
Emerging insights in the management of hemoglobin E beta thalassemia
Authors: Olivieri Nancy F. , Thayalsuthan Vivekanandan , O’Donnell Angela , Premawardhena Anuja , Rigobon Christopher , Muraca Giulia , Fisher Christopher , Weatherall David J.
Published: August 2010

Globally, hemoglobin (Hb) E β thalassemia accounts for approximately half the severe forms of β thalassemia. Because of its wide clinical diversity and the ability of patients with this condition to adapt unusually well to low hemoglobin levels, the management of Hb E β thalassemia, particularly the decision to instigate regular blood transfusion, is particularly difficult. Here, we present a summary of our work in patients with this condition, which attempts to define clinical, adaptive, and genetic factors of possible value in determining the early management of this condition.
Pulmonary hypertension in thalassemia
Authors: Morris Claudia R. , Vichinsky Elliott P.
Published: August 2010

Pulmonary hypertension (PH) is common in thalassemia and contributes to mortality. Advancing age and a history of splenectomy are major risk factors in this population. The etiology of PH is multifactorial, involving a complex interaction of platelets, the coagulation system, erythrocytes, and endothelial cells along with inflammatory and vascular mediators. The long‐term effect of splenectomy, red cell membrane pathology, coagulation abnormalities, low nitric oxide (NO) bioavailability, excess arginase activity, platelet activation, oxidative stress, iron overload, and chronic hemolysis play a role. The process of hemolysis disables the arginine‐NO pathway through the simultaneous release of erythrocyte arginase and cell‐free hemoglobin. Both NO and its obligate substrate arginine are rapidly consumed. The biological consequences of hemolysis on NO bioavailability ultimately translate into the clinical manifestations of PH. Guidelines for the management of PH in thalassemia have not yet been established; however, clinical trials are ongoing in an effort to guide future therapy.
A preclinical approach for gene therapy of β‐thalassemia
Authors: Breda Laura , Kleinert Dorothy A. , Casu Carla , Casula Laura , Cartegni Luca , Fibach Eitan , Mancini Irene , Giardina Patricia J. , Gambari Roberto , Rivella Stefano
Published: August 2010

Lentiviral‐mediated β‐globin gene transfer successfully treated β‐thalassemic mice. Based on this result, clinical trials were initiated. To date, however, no study has investigated the efficacy of gene therapy in relation to the nature of the different β‐globin mutations found in patients. Most mutations can be classified as β0 or β+, based on the amount of β‐globin protein produced. Therefore, we propose that a screening in vitro is necessary to verify the efficacy of gene transfer prior to treatment of individual patients. We used a two‐phase liquid culture system to expand and differentiate erythroid progenitor cells (ErPCs) transduced with lentiviral vectors. We propose the use of this system to test the efficiency of lentiviral vectors carrying the human β‐globin gene, to correct the phenotype of ErPCs from patients preparing for gene therapy. This new approach might have profound implications for designing gene therapy and for understanding the genotype/phenotype variability observed in Cooley's anemia patients.
Hematopoietic stem cell lodgment in the adult bone marrow stem cell niche
Authors: LAM B. S. , ADAMS G. B.
Published: August 2010

Treatment of malignant blood disorders, such as leukemia, that can provide a better chance of long‐term remission involves myeloablation followed by transplantation of matched donor hematopoietic stem cells (HSCs). For successful engraftment and re‐establishment of hematopoiesis to occur in the recipient, the transplanted HSCs must first migrate from the blood circulation to the bone marrow (BM), a process known as homing, then localize and anchor in suitable microenvironments within the BM, a process known as lodgment. After lodgment, the specific fate of the transplanted HSCs is determined through complex, bidirectional interactions with various stromal cell components in the niche. Ultimately, these interactions dictate the clinical outcome of the transplantation. Through the use of transgenic mouse models, considerable evidence has been accumulated in an attempt to unveil the possible underlying mechanisms that govern these processes. Here, we will emphasize the major factors that are involved in the regulation of lodgment of transplanted HSCs. Specifically, we will first introduce early observations on the spatial distribution of hematopoietic progenitors within the BM, then we will discuss the soluble factors, chemokines, cell–cell interactions, and cell–matrix interactions that have been studied and known to influence the site of HSC lodgment within the BM following transplantation.
THE ROLE OF COMMUNITY EDUCATORS IN ACHIEVING AUSTRALIAN HEALTH GOALS: A PUBLIC HEALTH APPROACH TO WEIGHT CONTROL ON THE NORTH COAST, NSW
Authors: James Ray , van Beurden Eric , Steiner Cave , Tyler Colin , Fardon Karen
Published: August 2010

This paper describes the recruitment, training and supervision of Community Educators for weight‐control programs, reports the results they have achieved to date, and offers suggestions for improving similar programs. This material is discussed in relation to suggestions about nutrition published by the Better Health Commission.
Notes on Calceola Sandalina and a New Variety From Shuimokou, N.W. Szechuan, China*
Authors: Chi Yungshen S.
Published: August 2010

The three German subspecies of Calceola sandalina—C. sandalina, C. sandalina alta, and C. sandalina westfalica.—are variations of the same species C. sandalina, according to different facies of the beds, as already noted by Lotze and Chernyshev. These subspecies are only of local importance, for even in Europe there are some exceptions as pointed out by Richter in the case of the forms from Asturias in North Spain and Moravia in Central Czechoslovakia.

Both the Russian and Chinese forms are distinct varieties of the cosmopolitan species C. sandalina. The Chinese form is found in the lower bed of the Middle Devonian both according to palæontological and stratigraphical evidence, but it bears some characters of C. sandalina alta and C sandalina westfalica from the middle and upper part of the Middle Devonian respectively. It is, however, easily distinguished from both of them by the small size and the combination of characters of the two.

In closing I wish to tender my cordial thanks to Merrs. H. C. Tan and C. Y. Lee for their kindness in submitting to me the materials collected by them and for their personal communications regarding it ; also to Mr. T. C. Lee who furnished some stratigraphical notes of the Shuimokou region made while collecting the fossils. Special acknowledgement is due to Dr. A. W. Grabau who read the manuscript of this paper, and gave me valuable suggestions.
The delimitation of Gelasine (Iridaceae), and G. uruguaiensis sp. nov. from Uruguay
Authors: Ravenna Pierfelice
Published: August 2010

The generic concept of Gelasine Herb. (Iridaceae) is reviewed, and the characters discussed in connection with Sphenostigma Bak., a synonym of Gelasine. The reduction of Sphenostigma is further justified on account of overlapping features. A new species from Uruguay, G. uruguaiensis Rav. sp. nov., is described and illustrated. This is shown to include two subspecies: ssp. uruguaiensis, and ssp. orientalis ssp. nov. The chromosome number of the latter is 2n = 14.
Pattern of variation of agamospermous Limonium (Plumbaginaceae) in the British Isles
Authors: Ingrouille M. J. , Stace C. A.
Published: August 2010

An investigation of cytological, palynological, and taxometric variation in Limonium binervosum (G. E. Sm.) C. E. Salmon has revealed an extensive pattern of hierarchical relationships within this agamospermous group in the British Isles. The group is either triploid (2n = 27) or aneuploid tetraploid (usually 2n = 35) with a highly jumbled karyotype. Pollen is either not produced or of very low stainability (in the range 0–38%). Well stained pollen grains are usually abnormally large resulting from a failure of a meiotic division. These facts as well as the presence of only a single self‐incompatible polledstigma morph in the majority of the group suggest that it is obligately agamospermic. The very strong correlation of taxometric relationship and geographical distance between variants suggests that evolution in the group has occurred by the gradual accumulation of mutations giving rise to morphologically and geographically related seed clones. The hierarchical pattern of variation as revealed by cluster analysis has been used as the basis of a hierarchical classification of the group.
Plasmatubules – real modifications of the plasmalemma
Authors: Harris N. , Chaffey N. J.
Published: August 2010

Plasmatubules are specific (approximately 20 nm diameter) evaginations of the plasmalemma, found at sites where high solute flux from apoplast to symplast is known, or inferred, to occur for short periods. First described in the distal, endosperm, end of barley scutellar epithelial cells, their structure has subsequently been confirmed using a range of both aqueous and non‐aqueous fixation techniques. Plasmatubules have now been described in a range of tissues and species, and examination of published micrographs indicates that this range could be extended further.
Micromorphology of seeds of Ornithogalum (Hyacinthaceae) in North Africa
Authors: Moret J. , Couderc H. , Bari A. , Delarue Y.
Published: August 2010

The micromorphology of the seeds of species of Ornithogalum genus found in North Africa is studied by SEM. Each species is characterized by a specific ornamentation which gives a high systematic value to this character. The ornamentation of the seed undergoes deep modifications during dessiccation. The supraspecific grouping based on this character do not correspond with the traditional classification of the genus. The phyletic value of this character is discussed.
Anti-pigmentary activity of fucoxanthin and its influence on skin mRNA expression of melanogenic molecules
Authors: Shimoda Hiroshi , Tanaka Junji , Shan Shao-Jie , Maoka Takashi
Published: August 2010

Objectives

Carotenoids and retinoic acid derivatives are topically applied for sun-protective and whitening purposes. Fucoxanthin is a carotenoid derived from edible sea algae, but its effect on melanogenesis has not been established. Therefore, we examined the effect of fucoxanthin on melanogenesis.

Methods

Inhibitory effects on tyrosinase activity, melanin formation in B16 melanoma and skin pigmentation in UVB-irradiated guinea-pigs were evaluated. To elucidate the action of fucoxanthin on melanogenesis, its effect on skin melanogenic mRNA expression was evaluated in UVB-irradiated mice. Fucoxanthin was given topically or orally to mice once a day and UVB irradiation was applied for 14 days. The effect of fucoxanthin on skin melanogenic mRNA expression was evaluated by real time reverse transcription polymerase chain reaction.

Key findings

Fucoxanthin inhibited tyrosinase activity, melanogenesis in melanoma and UVB-induced skin pigmentation. Topical application of fucoxanthin (1%) significantly suppressed mRNA expression of cyclooxygenase (COX)-2, endothelin receptor A, p75 neurotrophin receptor (NTR), prostaglandin E receptor 1 (EP1), melanocortin 1 receptor (MC1R) and tyrosinase-related protein 1. The suppression of p75NTR, EP1 and MC1R expressions was observed at 0.01% application. Also, oral application of fucoxanthin (10 mg/kg) significantly suppressed expression of COX-2, p75NTR, EP1 and MC1R.

Conclusions

These results suggest that fucoxanthin exhibits anti-pigmentary activity by topical or oral application in UVB-induced melanogenesis. This effect of fucoxanthin may be due to suppression of prostaglandin (PG) E2 synthesis and melanogenic stimulant receptors (neurotrophin, PGE2 and melanocyte stimulating hormone expression).
Diphenyl diselenide in its selenol form has dehydroascorbate reductase and glutathione S-transferase-like activity dependent on the glutathione content
Authors: Luchese Cristiane , Nogueira Cristina W
Published: August 2010

Objectives

The antioxidant action of diphenyl diselenide ((PhSe)2) is attributed to the mechanism by which (PhSe)2 has pharmacological activity. Although (PhSe)2 has glutathione peroxidase mimetic activity, the exact mechanism involved in its antioxidant effect has not yet been completely elucidated. In the present study, mechanisms involved in the antioxidant property of (PhSe)2 (1–50 µm) were investigated.

Methods

Dehydroascorbate (DHA) reductase- and glutathione S-transferase (GST)-like activity, 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical-scavenging activity and the protection against the oxidation of Fe2+ were evaluated.

Key findings

(PhSe)2 at concentrations equal to, or greater than, 5 µm showed DHA reductase- and GST-like activity. (PhSe)2 was not a scavenger of DPPH or ABTS radicals and did not protect against the oxidation of Fe2+.

Conclusions

These results clearly indicated that DHA reductase- and GST-like activity are the mechanisms involved in the antioxidant effect of (PhSe)2.
SU‐GG‐T‐325: The Effects of Neurosurgical Titanium Mesh on Radiation Dose in the Gamma Knife
Authors: Chin K , Rakowski J
Published: August 2010

Purpose: To investigate the impact of titanium neurosurgical mesh and bone cement on Gamma Knife dose distributions. Methods and Materials: Radiation properties of several meshes and bone cement were evaluated using a Theratron Co‐60 teletherapy unit. The mesh that caused the largest perturbation of the beam was then studied in the Leksell Gamma Knife. A head phantom was constructed using a plaster skull and ballistics gel. A section of the skull was removed and replaced with mesh. Two plans were created in the Leksell GammaPlan treatment planning software, one comprising a single 18 mm diameter shot centered at 2 cm below the surface of the phantom, and one 5cm below the surface. The plans were delivered to the phantom with bone and with mesh for a total of four deliveries. Dose profiles were measured in the coronal plane along with surface dose using GafChromic film, analyzed using RIT and ImageJ. Results: For the shallow lesion at 2cm depth, the measured maximum dose with the mesh was 5% less than the measured dose with the intact skull. For the lesion at 5 cm depth, the measured maximum dose with the mesh was 2% less than the measured dose with bone. At the surface immediately above the mesh, there was a 70% increase in dose. Conclusion: This work is significant in evaluating the need to modify a Gamma Knife SRS treatment plan when titanium mesh is present. For shallow lesions near the mesh, there is an associated a 5% reduction in maximum dose, and a 1 mm reduction in the 50% isodose diameter. These values decreased to 2% and 0 mm at 5 cm depth. However, for either depth, the dose at the mesh surface was increased by 68%, due to backscatter from the mesh.
SU‐GG‐T‐365: Backscatter Factor Measurements Using Gafchromic EBT2 Film
Authors: Hill R , Smith L , Kim J , Nakano M , Kuncic Z
Published: August 2010

Purpose: To evaluate the accuracy of Gafchromic EBT2 film in the determination of kilovoltage x‐ray backscatter factors. Method and Materials: Backscatter factors (BSFs) were measured for x‐rays beams in the energy range 50 to 280 kVp and field sizes from 2 to 6 cm diameter. Each BSF was determined by placing a 2×2 cm square of EBT2 film at the end of the applicator either in‐air or at the surface of a solid water phantom. The optical density (OD) at the center of each film was measured 24 hours after irradiation using a point densitometer. An OD versus dose calibration curve was determined for each x‐ray beam energy using the 6 cm diameter applicator and then used to determine the dose for each film sample. Reference BSFs were calculated by interpolation of the data in the AAPM TG61 kilovoltage dosimetry protocol. An uncertainty analysis in BSF determination was performed using the ISO methodology. Results: The agreement between measured and calculated BSFs was within 3.8% for the majority of the film measurements. This agreement was for all the energies and field sizes studied and based on multiple film measurements. However a small number of measurements gave dose differences of up to 10% between films irradiated under the same conditions and these films were discarded. These differences were attributed to variations in the chemical composition on the film leading to differences in the relative photoabsorption. Conclusion: We have demonstrated that Gafchromic EBT2 film is potentially suitable for the determination of kilovoltage x‐ray backscatter factors but not as accurate as the previous version Gafchromic EBT film.1
Sci—Thur PM: YIS — 01: Computational and Experimental Methods to Address the Limitations of Reconstructing Linac Photon Spectra from Transmission Measurements
Authors: Ali ESM , McEwen M , Rogers DWO
Published: August 2010

In the past two decades, the ill‐conditioned problem of unfolding linac photon spectra from transmission measurements has been extensively investigated. Previous studies suffer from various limitations that affect the accuracy and robustness of the unfolding. The goal of this study is to address the limitations of unfolding in general, and using parameterization of the spectrum in particular. To this end, the following new and refined methods are implemented. Different attenuator materials and different buildup caps are simultaneously used for better energy differentiation in most of the megavoltage energy range. The spectra are described using a new flexible and physics‐based functional form validated against more than 70 realistic spectra. The radiation detection system is modeled accurately using the EGSnrc usercodes BEAMnrc and cavity. Forward Compton scatter in the attenuators is modeled and corrected for. The proposed methods are validated experimentally on NRC research linac whose incident electron beam parameters are accurately known to 0.5% and its spectra have been independently measured using a NaI detector. A linear system was built to automatically drive attenuator lengths one at a time into the beam, which reduces acquisition time and beam instability uncertainties. Causes for experimental Type B uncertainties (leakage, polarity and scatter) are being investigated, particularly for small transmission signals. Results show that the proposed methods significantly improve the accuracy and robustness of unfolding in the presence of realistic experimental noise. Improvements by factors of 4 and 8 have been achieved in the accuracy of spectral unfolding and maximum energy estimation, respectively.
RELATIVISTIC COULOMB PROBLEM FOR Z LARGER THAN 137
Authors: ALHAIDARI A. D.
Published: August 2010

We propose a relativistic one-parameter Hermitian theory for the Coulomb problem with an electric charge greater than 137. In the nonrelativistic limit, the theory becomes identical to the Schrödinger–Coulomb problem for all Z. Moreover, it agrees with the Dirac–Coulomb problem to order (αZ)2, where α is the fine structure constant. The vacuum in the theory is stable and does not suffer from the "charged vacuum" problem for all Z. Moreover, transition between positive and negative energy states could be eliminated. The relativistic bound states energy spectrum and corresponding spinor wave functions are obtained.
ATMOSPHERIC MUON FLUX AT PEV ENERGIES
Authors: SINEGOVSKY S. I. , KOCHANOV A. A. , SINEGOVSKAYA T. S. , MISAKI A. , TAKAHASHI N.
Published: August 2010

In the near future, the energy region above few hundreds of TeV may really be accessible for measurements of the atmospheric muon spectrum with IceCube array. Therefore, one expects that muon flux uncertainties above 50 TeV, related to a poor knowledge of charm production cross-sections and insufficiently examined primary spectra and composition, will be diminished. We give predictions for the very high-energy muon spectrum at sea level, obtained with the three hadronic interaction models, taking into account also the muon contribution due to decays of the charmed hadrons.
ANALYSIS OF IMPOSSIBILITY OF TESTING SPATIAL NONCOMMUTATIVITY USING RYDBERG ATOMS IN THE VICINITY OF SADDLE-POINT IN CROSSED ELECTRIC AND MAGNETIC FIELDS
Authors: ZHANG JIAN-ZU , HE LI-MING , ZHU YUN-XIA
Published: August 2010

In relation to the current controversy over the need for an experimental test of spatial noncommutativity at the normal quantum scale, the spectra of a Rydberg electron in the vicinity of the saddle-point in a suitable combination of crossed electric and magnetic fields are investigated in both cases of commutative space and noncommutative space. Its local behavior around the saddle-point is clarified. An unbounded mode is revealed. It describes the unbounded direction along which the electron will escape the vicinity of the saddle-point, which means that it is impossible to locate electronic states. This finding indicates that the possibility of testing spatial noncommutativity in the vicinity of the saddle-point is ruled out. Because this unbounded mode applies only to states near the saddle-point, not to those from the outer well, it is suggested that if any test of spatial noncommutativity can be performed by using atoms in the crossed-field, then the test must be performed using states from the outer well, not those close to the saddle-point.
SOME BIANCHI TYPE-V COSMOLOGICAL MODELS IN BRANS–DICKE THEORY
Authors: SINGH J. K.
Published: August 2010

The Bianchi type-V cosmological models have been investigated in the context of Brans–Dicke theory in the presence as well as absence of the magnetic field. The physical and kinematical behaviors of the models have been discussed. The energy conditions of the models have also been examined.
THE NEXT-TO-MINIMAL SUPERSYMMETRIC EXTENSION OF THE STANDARD MODEL REVIEWED
Authors: MANIATIS M.
Published: August 2010

The next-to-minimal supersymmetric extension of the Standard Model (NMSSM) is one of the most favored supersymmetric models. After an introduction to the model, the Higgs sector and the neutralino sector are discussed in detail. Theoretical, experimental, and cosmological constraints are studied. Eventually, the Higgs potential is investigated in the approach of bilinear functions. Emphasis is placed on aspects which are different from the minimal supersymmetric extension.
EVALUATION OF THE GRAVITON TWO-POINT FUNCTION IN DE SITTER SPACE
Authors: DEHGHANI M.
Published: August 2010

After a brief review of the linearized gravity in de Sitter (dS) four-dimensional space and ambient flat five-dimensional notations, the linearized field equation is written in terms of the Casimir operators of dS group. It is shown that the field equation is gauge invariant under some special gauge transformations. Because of this gauge freedom, a gauge-fixing parameter c is inserted in the field equation. It is shown that the solution to the field equation can be written as the multiplication of a generalized symmetric rank-2 polarization tensor and a massless minimally coupled scalar field in ambient space notations. The graviton two-point function has been thoroughly calculated, which is dS-invariant and free of any divergences. This two-point function has been expressed in terms of the intrinsic dS coordinates, from its ambient space counterpart, which is clearly dS-invariant and free of any divergences again.
COMPACTIFICATION OF TYPE IIB THEORY WITH FLUXES AND AXION–DILATON STRING COSMOLOGY
Authors: KONISHI EIJI , MAHARANA JNANADEVA
Published: August 2010

Compactification of type IIB theory on torus, in the presence of fluxes, is considered. The reduced effective action is expressed in manifestly S-duality invariant form. Cosmological solutions of the model are discussed in several cases in the Pre-Big Bang scenario.
A logic for state-modifying authorization policies
Authors: Becker Moritz Y. , Nanz Sebastian
Published: August 2010

Administering and maintaining access control systems is a challenging task, especially in environments with complex and changing authorization requirements. A number of authorization logics have been proposed that aim at simplifying access control by factoring the authorization policy out of the hard-coded resource guard. However, many policies require the authorization state to be updated after a granted access request, for example, to reflect the fact that a user has activated or deactivated a role. Current authorization languages cannot express such state modifications; these still have to be hard-coded into the resource guard. We present a logic for specifying policies where access requests can have effects on the authorization state. The logic is semantically defined by a mapping to Transaction Logic. Using this approach, updates to the state are factored out of the resource guard, thus enhancing maintainability and facilitating more expressive policies that take the history of access requests into account. We also present a sound and complete proof system for reasoning about sequences of access requests. This gives rise to a goal-oriented algorithm for finding minimal sequences that lead to a specified target authorization state.
A model of novice and expert navigation performance in constrained-input interfaces
Authors: Cockburn Andy , Gutwin Carl
Published: August 2010

Many interactive systems require users to navigate through large sets of data and commands using constrained input devices—such as scroll rings, rocker switches, or specialized keypads—that provide less power and flexibility than traditional input devices like mice or touch screens. While performance with more traditional devices has been extensively studied in human-computer interaction, there has been relatively little investigation of human performance with constrained input. As a result, there is little understanding of what factors govern performance in these situations, and how interfaces should be designed to optimize interface actions such as navigation and selection. Since constrained input is now common in a wide variety of interactive systems (such as mobile phones, audio players, in-car navigation systems, and kiosk displays), it is important for designers to understand what factors affect performance. To aid in this understanding, we present the Constrained Input Navigation (CIN) model, a predictive model that allows accurate determination of human navigation and selection performance in constrained-input scenarios. CIN identifies three factors that underlie user efficiency: the performance of the interface type for single-level item selection (where interface type depends on the input and output devices, the interactive behavior, and the data organization), the hierarchical structure of the information space, and the user's experience with the items to be selected. We show through experiments that, after empirical calibration, the model's predictions fit empirical data well, and discuss why and how each of the factors affects performance. Models like CIN can provide valuable theoretical and practical benefits to designers of constrained-input systems, allowing them to explore and compare a much wider variety of alternate interface designs without the need for extensive user studies.
Abstract only
Authors: Manubens Montserrat
Published: August 2010

The discussion of parametric polynomial systems is an old and important problem in many technical and mathematical applications. To recall its importance it suffices to remember the well-known discussions of parametric linear systems and how useful they are for applications. However, many practical problems are associated to non-linear systems, in which the study of the nature of the solutions (i.e. no solution, finite number of solutions, degree of freedom of the solutions, etc) is very important depending on the values of the parameters.

Since Gröbner bases were introduced, various approaches have been developed for this problem. Many authors have studied the subject during the last 15 years, among others we can highlight D. Lazard, D. Duval, P. Gianni, M. Kalkbrenner, V. Weispfenning, T. Mora, M. Moreno-Maza, L.Gonzalez-Vega, D. Kapur, D. Wang, Y. Sato, A. Suzuki, for the relevance of their contributions.

The development of the subject of this thesis was initiated in 2000 with the first Montes' algorithm dispgb for discussing parametric polynomial systems using Gröbner bases, published in 2002 in the Journal of Symbolic Computation. Montes' algorithm has progressed from that moment, until the final obtention of the Minimal Canonical Comprehensive Gröbner System (MCCGS) of a parametric ideal.

During the period 2003-2007 I had the great opportunity and pleasure to participate in this challenging project. My personal contribution to the project consisted of the implementation and improvement of a high number of algorithms that have conformed the evolution up to the current algorithm MCCGS, and updating the theory and algorithms that were initially disperse and partially incomplete.

Given a polynomial system with parameters and a term order for the variables, the latest implementation of the algorithm MCCGS performs a discussion on the cancellation of some polynomials in the parameters. It obtains a set of ordered pairs consisting of a segment (constructible subset of the parameter space) and a basis (finite set of polynomials) such that

the set of all segments forms a partition of the parameter space;

for each pair, the substitution of the parameters in the basis by any value inside the corresponding segment, produces always the reduced Gröbner basis, with respect to the given term order, of the ideal generated by the substitution of the same values in the given polynomials;

the segments are uniquely determined by the given system and term order and moreover they are described in a canonical form;

the number of pairs in the obtained set is the minimum possible with these properties.

All implementations have been done in Maple, and the last release 7.0 is currently available on the web http://www-ma2.upc.edu/~montes/, which integrates the improvements made on the original Montes' algorithm and the final MCCGS algorithm.
On the Macaulay inverse system and its importance for the theory of linear differential equations with constant coefficients
Authors: Gröbner Wolfgang
Published: August 2010

When first studying Macaulay's
inverse systems
(for this, see [2, p. 65ff] first, then [3, page 37ff], and the excellent short exposition [1, page 66ff]), one can easily fall for the mistake that this is a difficult to understand, artificial construction of little value. Subsequent applications, which lead to a very suprising new insight, teach us better. In what follows, it will be shown how this shortcoming, insofar as it even exists, can be corrected in a simple way that draws on a new interpretation of the polynomial ring, which may be useful in and of itself. Macaulay's inverse system is thereby connected to the system of integrals of linear homogeneous differential equations with constant coefficients and loses its character of possible foreignness. At the same time, this work represents an attempt to establish relationships between two seemingly completely separate branches of mathematics, which may be useful and fruitful for both sides.
Abstract only
Authors: Mathews Deborah
Published: August 2010

To capitalize on multi-core processing, it would be good to perform big number arithmetic in parallel. While a performance increase equal to the number of processors is theoretically possible, our experiments show that inpractice the likelihood of gaining any performance increase for big number arithmetic through parallel processing is low. A speed-up approaching the number of processors was not achieved for multiplication until the operands had at least 215 bits. No performance gain was realized for addition. The base algorithm used for multiplication was O(n2) and, therefore, suboptimal. The expected performance gain achieved when parallelizing a more efficient base algorithm should be even smalle.
Clinical and Genetic Knowledge and Attitudes of Patients with Myotonic Dystrophy Type 1
Authors: Laberge L. , Prévost C. , Perron M. , Mathieu J. , Auclair J. , Gaudreault M. , Richer L. , Jean S. , Veillette S.
Published: August 2010

Aims: The goal was to assess clinical and genetic knowledge and attitudes in patients affected by myotonic dystrophy type 1 (DM1). Methods: Two hundred patients with molecular confirmation of the diagnosis of DM1 completed a multi-choice questionnaire. DM1 patients’ knowledge and views were compared to clinically normal DM1 noncarriers (n = 264) and controls (n = 1,474). Results: Knowledge of the DM1 mode of inheritance was better in noncarriers than in patients (p < 0.001). Noncarriers were more aware than DM1 patients of the common clinical characteristics of DM1 such as limitations in physical activities and problems related to employment, schooling, activities of daily living, parenthood, peer relationships, and personality (p < 0.001). Compared to controls, DM1 patients felt less informed about the availability of clinical genetic services (p < 0.05) and new genetic technologies (p < 0.001). Among patients, logistic regression revealed that each additional year of education (p < 0.05) and each additional 100 CTG repeats (p < 0.01), respectively, increased and decreased the odds of knowing the DM1 mode of inheritance by about 23% and 18% respectively, independently of age, age at onset of symptoms, gender, severity of muscular impairment, and intellectual quotient. Conclusions: DM1 patients’ genetic knowledge is significantly dependent of the level of education and the number of CTG repeats. Healthcare providers should be aware of this situation in order to adjust counselling and education accordingly.
Transparency as Contested Political Terrain: Who Knows What about the Global GMO Trade and Why does it Matter?
Authors: Gupta Aarti
Published: August 2010

This article explores the prospects for transparency to be a transformative force in global biosafety governance. It analyzes whether information disclosure can further a right to know and choose, and hence facilitate oversight over transnational transfers of genetically modified organisms (GMOs). It examines the question of “Whose right to know what and why?” with regard to GMOs in the agricultural commodity trade in relation to the global Cartagena Protocol on Biosafety. I argue that the limited disclosure obligations in this global context follow rather than shape market developments, and that complex infrastructures of sampling, testing and detection are required to put disclosed information to use. If so, rather than a normative right-to-know of importing countries, a competing norm of caveat emptor (let the buyer beware) prevails. I conclude that the potential of transparency to empower remains unrealized, particularly for the poorest countries most reliant on globally-induced disclosure.
Transparency in Nonstate Certification: Consequences for Accountability and Legitimacy
Authors: Auld Graeme , Gulbrandsen Lars H.
Published: August 2010

Nonstate certification programs have formed in the past 20 years to address social and environmental problems associated with production practices in several economic sectors. These programs embody the idea that information disclosure can be a tool for NGOs, investors, governments, and consumers to support high performers and hence, advocates hope, place upward pressure on sector-wide practices. Many unanswered questions remain, however, about information disclosure's practices and outcomes. We compare the use of procedural and outcome transparency in the rule-making and auditing processes of the Marine Stewardship Council (MSC) and Forest Stewardship Council (FSC). We highlight key differences in how transparency relates to accountability and legitimacy of the programs. The MSC uses transparency and stakeholder consultation instrumentally, whereas the FSC treats them as ends unto themselves. This underscores the importance of considering transparency alongside other governance aspects, such as who the eligible stakeholders are and who gets decision-making power.
Reply
Authors: Illingworth A. J. , Latham J.
Published: August 2010

No abstract available.
The Detection and Significance of Diurnal Pressure and Potential Vorticity Anomalies East of the Rockies
Authors: Li Yanping , Smith Ronald B.
Published: August 2010

Harmonic analysis of pressure, temperature, and precipitation data from 1000 Automated Surface Observing System (ASOS) stations reveals a mix of stationary and east–west moving disturbances east of the Rockies. Optimization of the pressure data using a “temperature-based tide assumption” separates a strong sun-following continentally enhanced tide from a smaller eastward-propagating wave (EPW). The latter signal moves at a similar speed to the previously discovered eastward-moving precipitation systems. Analysis of ASOS summer precipitation data confirms eastward propagation, but east of 90°W it shows nonpropagating diurnal convection at a fixed local time (i.e., 1800 LST). Analysis of winter days still finds the EPW, suggesting that it is the cause and not the result of the propagating precipitation.

A possible mechanism for the EPW is developed from the linear Bousinesq equations with heating and wind shear. Solutions show eastward-moving diurnal pulses of potential vorticity (PV) generated by imposed heating over the Rockies. Because of the background shear, these pulses produce vertical motion in the lower troposphere.

The PV hypothesis for precipitation propagation was tested with North American Regional Reanalysis (NARR) data. Diurnal drifting thermal and PV anomalies are clearly found near the 500- and 600-hPa levels in both winter and summer. In winter, the PV signal is weaker, moves faster, and does not influence precipitation. The existence of the winter PV signal again suggests that it is the cause, not the effect, of summer propagating precipitation.
Beyond Gaussian Statistical Modeling in Geophysical Data Assimilation
Authors: Bocquet Marc , Pires Carlos A. , Wu Lin
Published: August 2010

This review discusses recent advances in geophysical data assimilation beyond Gaussian statistical modeling, in the fields of meteorology, oceanography, as well as atmospheric chemistry. The non-Gaussian features are stressed rather than the nonlinearity of the dynamical models, although both aspects are entangled. Ideas recently proposed to deal with these non-Gaussian issues, in order to improve the state or parameter estimation, are emphasized.

The general Bayesian solution to the estimation problem and the techniques to solve it are first presented, as well as the obstacles that hinder their use in high-dimensional and complex systems. Approximations to the Bayesian solution relying on Gaussian, or on second-order moment closure, have been wholly adopted in geophysical data assimilation (e.g., Kalman filters and quadratic variational solutions). Yet, nonlinear and non-Gaussian effects remain. They essentially originate in the nonlinear models and in the non-Gaussian priors. How these effects are handled within algorithms based on Gaussian assumptions is then described. Statistical tools that can diagnose them and measure deviations from Gaussianity are recalled.

The following advanced techniques that seek to handle the estimation problem beyond Gaussianity are reviewed: maximum entropy filter, Gaussian anamorphosis, non-Gaussian priors, particle filter with an ensemble Kalman filter as a proposal distribution, maximum entropy on the mean, or strictly Bayesian inferences for large linear models, etc. Several ideas are illustrated with recent or original examples that possess some features of high-dimensional systems. Many of the new approaches are well understood only in special cases and have difficulties that remain to be circumvented. Some of the suggested approaches are quite promising, and sometimes already successful for moderately large though specific geophysical applications. Hints are given as to where progress might come from.
Some Insights into the Characteristics and Dynamics of the Chilean Low-Level Coastal Jet
Authors: Jiang Qingfang , Wang Shouping , O’Neill Larry
Published: August 2010

The characteristics and dynamics of the Chilean low-level coastal jet (CLLCJ) are examined here through diagnosing real-time mesoscale model forecasts in support of the Variability of the American Monsoon System (VAMOS) Ocean–Cloud–Atmosphere Land Study (VOCALS) and additional sensitivity simulations. The forecasted surface winds over the southeast Pacific compare favorably with available observations. According to the forecasts and sensitivity simulations, the Southeast Pacific high pressure system (SEPH) plays a primary role in driving the CLLCJ. The Andes significantly intensify the CLLCJ mainly through interacting with the SEPH and anchoring a baroclinic zone along the Chilean coast. The land–sea differential heating also enhances the CLLCJ by strengthening the coastal baroclinic zone. Based on the location of the SEPH center, the CLLCJ can be separated into two types: a strong-forcing jet, with the SEPH close to the central Chilean coastline; and a weak-forcing jet, with the SEPH centered far away from the coastline. The former is much more intense and associated with stronger interaction between the SEPH and the Andes.

The CLLCJ is slightly supergeostrophic within the marine boundary layer top inversion, where weak easterlies develop, and subgeostrophic in the turbulent boundary layer below, where westerlies are present. The inversion easterlies induce strong subsidence along the coast, which contributes to the formation of the coastal low and the coastal baroclinic zone.
A Comparative Analysis of MEXT English Reading Textbooks and Japan’s National Center Test
Authors: Underwood Paul
Published: August 2010

Despite the influence of changing demographics in Japan, the National Center Test for University Entrance Exams continues to assert an ever increasing role in the process of university admissions. In preparation for this examination, the majority of senior high school students learn from textbooks approved by the Japanese Ministry of Education, Culture, Sports, Science, and Technology (MEXT). This study compares Section Six of the 2003-2007 and 2008-2009 National Center Test English reading examination with three widely used MEXT senior high school reading textbooks. By triangulating analyses of vocabulary, reading ease/grade level indices, reading skills, and comprehension item formats, thereby expanding the methodologies of previous research in this area, the study poses the question:To what degree do the text and comprehension tasks of MEXT textbooks compare with those which students will be expected to comprehend in the National Center Test reading examination? Updating the results of earlier studies, the descriptive and inferential statistics reveal that while the vocabulary levels of the textbook now appear to correspond more closely with recent versions of the examination, further alignment of readability, grade levels, and comprehension tasks is necessary if MEXT textbooks are to support the development of reading proficiency now required.
Contradictions in media sport culture: The reinscription of football supporter traditions through online media
Authors: Ruddock Andy , Hutchins Brett , Rowe David
Published: August 2010

The website MyFootballClub offers a novel experience for football fans. Through the design and operation of a website, it attempts to reinvigorate fan participation in a heavily mediated, multibillion-dollar global industry. Charging a membership fee of £35 (47), MFC purchased a controlling stake in a non-league English football club, with power over management decisions handed to online members. Attracting more than 30,000 members from over 70 nations, this exercise in online ‘football democracy’ is significant for more than its novelty value and the spawning of similar exercises in other countries. MFC offers an important case study in which ‘media space’ is privileged above all others, claiming to resurrect football-based organic community bonds that were supposedly disrupted by media, but doing so within media. MFC demonstrates how media sport synthesizes apparent contradictions, so that members can recreate football-as-folk-culture fantasies through the processes of mediation and commodification that are otherwise blamed for killing ‘the people’s game’.
The Limits of Hospitality: Political Philosophy, Undocumented Migration and the Local Arena
Authors: Friese Heidrun
Published: August 2010

How to hospitably welcome refugees and migrants presents urgent questions for social and political thought. Current debates can be attributed to three discursive fields. Liberal versions hold that there are good reasons for political and legal limits of hospitality, critical perspectives advocate a renewed cosmopolitanism and, finally, deconstructive perspectives focus on the demand of unconditional hospitality as an absolute ethical requirement. These concepts trouble the conventional congruence of citizenship and bounded territory that make up modern nation states, on the one hand. On the other hand, they affirm the rights of political communities to decide on the contents and the extent of the universal duty to host those endangered. Taking the Mediterranean and the local arena (Lampedusa) as the example, the article, which is based on extensive, multi-sited anthropological field research, engages with the tensions and limits inherent in current notions of hospitality.