bluuebunny/crossref_metadata_2025 huggingface dataset:
A light test to measure stability of edible oils
Authors: Moser Helen A. , Evans C. D. , Cowan J. C. , Kwolek W. F.
Published: February 2007

The effect of light on the flavor of edible oils and of various fat‐containing foods is reviewed to show its importance in food studies and the need for a method of evaluation. Such a test, in which fluorescent light is used in an easily assembled unit, has been developed, and the parameters for its use have been determined. Identical samples of soybean oil exposed on 10 different days and organoleptically evaluated show the method to be reproducible with a standard deviation of 0.79 with a scoring system of 1舑10. This method was then applied to soybean, cottonseed, safflower and hydrogenated‐winterized soybean oils, and a light‐exposure value was determined for each oil based on a comparison with accelerated storage procedures ordinarily used. Advantages of this light test over current procedures are the short time required for completion, the reduction of variation by a controlled light source, reproducibility of results and its adaptability to related food products.
N− 3 PUFAs modulate global gene expression profile in cultured rat cardiomyocytes. Implications in cardiac hypertrophy and heart failure
Authors: Bordoni Alessandra , Astolfi Annalisa , Morandi Luca , Pession Andrea , Danesi Francesca , Di Nunzio Mattia , Franzoni Monica , Biagi PierLuigi , Pession Annalisa
Published: February 2007

In cardiac cells the effects of n
− 3 PUFAs on the whole genome are still unknown despite their recognized cardioprotective effects and ability to modulate gene expression. We have evaluated the effects of n
− 3 PUFAs supplementation on the global gene expression profile in cultured neonatal rat cardiomyocytes, detecting many genes related to lipid transport and metabolism among the upregulated ones. Many of the downregulated genes appeared related to inflammation, cell growth, extracellular and cardiac matrix remodelling, calcium movements and ROS generation. Our data allow to speculate that the cardioprotective effect of n
− 3 PUFAs is related to a direct modulation of genes in cardiac cells.
PROMETHEUS OR ICARUS? IDEA AND IDEOLOGY IN NONO'S ‘AL GRAN SOLE CARICO D'AMORE’
Authors: Fearn Raymond
Published: February 2007

Did Luigi Nono succeed in creating the ‘new music theatre’ that he wished to create – and does his second theatrical work Al gran sole carico d'amore (1975) represent such a theatre? The theatre was certainly a constant siren beckoning the composer. Right from the start of his creative life, Nono's primary concern as a composer had been with musical expression, and he cast the most powerful and often provocative literary texts in musical terms, as can be seen in the settings he made of Lorca poems during the early 1950s.
Evaluating water stress controls on primary production in biogeochemical and remote sensing based models
Authors: Mu Qiaozhen , Zhao Maosheng , Heinsch Faith Ann , Liu Mingliang , Tian Hanqin , Running Steven W.
Published: February 2007

Water stress is one of the most important limiting factors controlling terrestrial primary production, and the performance of a primary production model is largely determined by its capacity to capture environmental water stress. The algorithm that generates the global near‐real‐time MODIS GPP/NPP products (MOD17) uses VPD (vapor pressure deficit) alone to estimate the environmental water stress. This paper compares the water stress calculation in the MOD17 algorithm with results simulated using a process‐based biogeochemical model (Biome‐BGC) to evaluate the performance of the water stress determined using the MOD17 algorithm. The investigation study areas include China and the conterminous United States because of the availability of daily meteorological observation data. Our study shows that VPD alone can capture interannual variability of the full water stress nearly over all the study areas. In wet regions, where annual precipitation is greater than 400 mm/yr, the VPD‐based water stress estimate in MOD17 is adequate to explain the magnitude and variability of water stress determined from atmospheric VPD and soil water in Biome‐BGC. In some dry regions, where soil water is severely limiting, MOD17 underestimates water stress, overestimates GPP, and fails to capture the intraannual variability of water stress. The MOD17 algorithm should add soil water stress to its calculations in these dry regions, thereby improving GPP estimates. Interannual variability in water stress is simpler to capture than the seasonality, but it is more difficult to capture this interannual variability in GPP. The MOD17 algorithm captures interannual and intraannual variability of both the Biome‐BGC‐calculated water stress and GPP better in the conterminous United States than in the strongly monsoon‐controlled China.
Ultraviolet embossed alignment layer for flexible liquid crystal display
Authors: Hah Hyundae , Sung Shi-Joon , Park Jung-Ki
Published: February 2007

Ultraviolet (UV) embossed alignment layer for the flexible liquid crystal display (LCD) was fabricated to prevent problems encountered with the thermal treatment of the rubbing process on the plastic substrate. The mechanical stability against bending deformation was achieved by a phase-separated polymer wall. In a bent environment, the UV embossed alignment layer for the flexible LCD provided good liquid crystal properties and mechanical stability.
A catalytic beacon sensor for uranium with parts-per-trillion sensitivity and millionfold selectivity
Authors: Liu Juewen , Brown Andrea K. , Meng Xiangli , Cropek Donald M. , Istok Jonathan D. , Watson David B. , Lu Yi
Published: February 2007

Here, we report a catalytic beacon sensor for uranyl (UO
2
2+
) based on an
in vitro
-selected UO
2
2+
-specific DNAzyme. The sensor consists of a DNA enzyme strand with a 3′ quencher and a DNA substrate with a ribonucleotide adenosine (rA) in the middle and a fluorophore and a quencher at the 5′ and 3′ ends, respectively. The presence of UO
2
2+
causes catalytic cleavage of the DNA substrate strand at the rA position and release of the fluorophore and thus dramatic increase of fluorescence intensity. The sensor has a detection limit of 11 parts per trillion (45 pM), a dynamic range up to 400 nM, and selectivity of >1-million-fold over other metal ions. The most interfering metal ion, Th(IV), interacts with the fluorescein fluorophore, causing slightly enhanced fluorescence intensity, with an apparent dissociation constant of ≈230 μM. This sensor rivals the most sensitive analytical instruments for uranium detection, and its application in detecting uranium in contaminated soil samples is also demonstrated. This work shows that simple, cost-effective, and portable metal sensors can be obtained with similar sensitivity and selectivity as much more expensive and sophisticated analytical instruments. Such a sensor will play an important role in environmental remediation of radionuclides such as uranium.
Multilevel Selection and the Major Transitions in Evolution
Authors: Okasha Samir
Published: February 2007

A number of recent biologists have used multilevel selection theory to help explain the major transitions in evolution. I argue that in doing so, they have shifted from a ‘synchronic’ to a ‘diachronic’ formulation of the levels of selection question. The implications of this shift in perspective are explored, in relation to an ambiguity in the meaning of multilevel selection. Though the ambiguity is well-known, it has never before been discussed in the context of the major transitions.
Feminism, Underdetermination, and Values in Science
Authors: Intemann Kristen
Published: February 2007

Several feminist philosophers of science have tried to open up the possibility that feminist ethical or political commitments could play a positive role in good science by appealing to the Duhem-Quine thesis and underdetermination of theories by observation. I examine several different interpretations of the claim that feminist values could play a legitimate role in theory justification and show that none of them follow from a logical gap between theory and observation. Finally, I sketch an alternative approach for defending the possibility that feminist political commitments could play a legitimate role in science.
Can Cumulative Selection Explain Adaptation?
Authors: Nanay Bence
Published: February 2007

Two strong arguments have been given in favor of the claim that no selection process can play a role in explaining adaptations. According to the first argument, selection is a negative force; it may explain why the eliminated individuals are eliminated, but it does not explain why the ones that survived (or their offspring) have the traits they have. The second argument points out that the explanandum and the explanans are phenomena at different levels: selection is a population-level phenomenon, whereas adaptation occurs on the individual level. Thus, selection can explain why individuals in a certain population have a certain trait, but it cannot explain why a certain individual has this trait. After pointing out that both arguments ignore the significance of the limitation of environmental resources, I will construe a positive argument for the claim that cumulative selection processes can, indeed, play a role in explaining adaptations.
Cardiometabolic Syndrome and Chronic Kidney Disease: What Is the Link?
Authors: Sarafidis Panteleimon A. , Whaley‐Connell Adam , Sowers James R. , Bakris George L.
Published: February 2007

The term metabolic syndrome or cardiometabolic syndrome describes the clustering of several cardiovascular and renal risk factors, including type 2 diabetes mellitus, central obesity, hypertension, and dyslipidemia. Over the past 15 years, several studies have examined the association between the metabolic/cardiometabolic syndrome or its central component, insulin resistance, with the presence of elevated urine albumin excretion. Intrarenal changes associated with the cardiometabolic syndrome result in elevated glomerular filtration rate, impaired pressure natriuresis, endothelial dysfunction related to changes in nitric oxide and, hence, impaired renal autoregulation and enhanced chronic inflammation. The aforementioned changes that occur in the cardiometabolic syndrome all contribute to the development of renal injury. While this review focuses on the epidemiology and mechanisms associated with vascular/renal injury, it must be remembered that prevention and treatment of kidney disease require a multifactorial approach. Weight loss through diet and exercise can reverse many of these pathophysiologic adaptations. Pharmacologic intervention should be aimed at achieving guideline goals and include insulin sensitizers to aid in tight glycemic control, lipid control, blockade of the renin‐angiotensin‐aldosterone system for blood pressure reduction, and anti‐inflammatory therapies.
Influence of sward condition on leaf tissue turnover in tall fescue and tall wheatgrass swards under continuous grazing
Authors: Agnusdei M. G. , Assuero S. G. , Fernández Grecco R. C. , Cordero J. J. , Burghi V. H.
Published: February 2007

Two experiments were carried out on a tall fescue sward in two periods of spring 1994 and on a tall wheatgrass sward in autumn 2001 and spring 2003 to analyse the effect of sward surface height on herbage mass, leaf area index and leaf tissue flows under continuous grazing. The experiment on tall fescue was conducted without the application of fertilizer and the experiment with tall wheatgrass received 20 kg P ha−1 and a total of 100 kg N ha−1 in two equal dressings applied in March (autumn) and end of July (mid‐winter).

Growth and senescence rates per unit area increased with increasing sward surface height of swards of both species. Maximum estimated lamina growth rates were 28 and 23 kg DM ha−1 d−1 for the tall fescue in early and late spring, respectively, and 25 and 36 kg DM ha−1 d−1 for tall wheatgrass in autumn and spring respectively. In the tall fescue sward, predicted average proportions of the current growth that were lost to senescence in early and late spring were around 0·40 for the sward surface heights of 30–80 mm, and increased to around 0·60 for sward surface heights over 130 mm. In the tall wheatgrass sward the corresponding values during spring increased from around 0·40 to 0·70 for sward surface heights between 80 and 130 mm. During autumn, senescence losses exceeded growth at sward surface heights above 90 mm. These results show the low efficiency of extensively managed grazing systems when compared with the high‐input systems based on perennial ryegrass.
The C‐terminus of pokeweed antiviral protein has distinct roles in transport to the cytosol, ribosome depurination and cytotoxicity
Authors: Baykal Ulku , Tumer Nilgun E.
Published: February 2007

Pokeweed antiviral protein (PAP) produced by pokeweed plants is a single‐chain (type I) ribosome‐inactivating protein (RIP) that depurinates ribosomes at the α‐sarcin/ricin loop of the large rRNA, resulting in inhibition of translation. Unlike the type II RIPs, which have an active and a binding moiety, PAP has only the active moiety. The mechanism by which toxins without a binding moiety gain access to cytosolic ribosomes is not known. We set up yeast as a simple and genetically tractable system to investigate how PAP accesses ribosomes and showed that the mature form of PAP is targeted to the cytosol from the endomembrane system in yeast. In the present study, we performed a systematic deletion analysis to identify the signal required for transport of PAP to the cytosol. We demonstrate here that processing of the C‐terminal extension and sequences at the C‐terminus of the mature protein are critical for its accumulation in the cytosol. Using a series of PAP mutants, we identified the C‐terminal signal and demonstrated that it is distinct from the sequences required for ribosome depurination and cytotoxicity. The C‐terminal motif showed sequence similarity to type II RIPs that retrotranslocate from the endoplasmic reticulum to the cytosol. These results demonstrate that a conserved sequence at the C‐terminus of a type I RIP mediates its transport to the cytosol and suggest that type I and II RIPs may use a common signal to enter the cytosol.
Contemporaryin vivoconfocal microscopy of the living human cornea using white light and laser scanning techniques: a major review
Authors: Patel Dipika V , McGhee Charles NJ
Published: February 2007

Abstract

In vivoconfocal imaging of the cornea has evolved exponentially over the last few decades and it has increasingly emerged from the laboratory to be used in the clinical setting in relation to inherited corneal diseases, corneal infections, contact lens wear and the effects of corneal surgery. This evolution has led to significant enhancement of our knowledge of the living cornea in both its physiological and pathological states. A number ofin vivoconfocal microscope devices using white, and more recently coherent, light sources have been developed to provide non‐invasive assessment of the corneal microstructure at a lateral resolution of 1–2 µm. The fundamental principles ofin vivoconfocal microscopy and the key differences between these devices are highlighted in this review. By providing a systematic review of the extensive literature on the human cornea, this perspective paper aims to provide an overview of howin vivoconfocal microscopy has contributed to our greater understanding of the human cornea in health, in disease, and following surgery, with a particular emphasis on quantitative data. The utility and limitations of available data are highlighted as are possibilities for the future development of this innovative technology.
A Test of the Differential Accuracy of the Maxillary Versus the Mandibular Dentition in Age Estimations of Immature Skeletal Remains Based on Developing Tooth Length
Authors: Cardoso Hugo F. V.
Published: February 2007

ABSTRACT: Liversidge and colleagues developed a method for predicting the age of immature skeletal remains based on the length of developing teeth. This quantitative method combines dental data from both jaws, except for the permanent lateral incisor, and because there are reasons to suspect that these two types of data are not identical and should not be combined, it raises concerns regarding the accuracy of the technique when applied differently to each jaw. In this study, the differential accuracy of the method was test when applied to the maxillary and mandibular dentition. The test sample is comprised of 57 Portuguese subadult skeletons of known age at death. Results suggest an overall high consistency between estimates obtained from both jaws, but for the permanent dentition only. In the deciduous dentition the age estimates obtained from the maxillary teeth tend to be greater than the age estimates obtained from the mandibular pair, and the differences are significant for the incisors and canine. Additionally, ages obtained from the maxillary deciduous canine also differ significantly from true chronological age. In the permanent dentition there were no differences between the ages provided by both jaws but both the maxillary and mandibular second molars show a significant tendency to underestimate true chronological age. Although this study cannot validate completely the method presented by Liversidge and colleagues, it does provide an important test to its accuracy and calls for further research into its overall performance, particularly with respect to the results obtained from both jaws.
Alternative Fuels in Fire Debris Analysis: Biodiesel Basics
Authors: Stauffer Eric , Byron Doug
Published: February 2007

ABSTRACT: Alternative fuels are becoming more prominent on the market today and, soon, fire debris analysts will start seeing them in liquid samples or in fire debris samples. Biodiesel fuel is one of the most common alternative fuels and is now readily available in many parts of the United States and around the world. This article introduces biodiesel to fire debris analysts. Biodiesel fuel is manufactured from vegetable oils and/or animal oils/fats. It is composed of fatty acid methyl esters (FAMEs) and is sold pure or as a blend with diesel fuel. When present in fire debris samples, it is recommended to extract the debris using passive headspace concentration on activated charcoal, possibly followed by a solvent extraction. The gas chromatographic analysis of the extract is first carried out with the same program as for regular ignitable liquid residues, and second with a program adapted to the analysis of FAMEs.
Pediatric Bipolar Disorder: Evidence‐Based Psychopharmacological Treatments
Authors: Hamrin Vanya , Pachler Maryellen
Published: February 2007

TOPIC:  Pediatric bipolar disorder can cause severe disturbances in global functioning. Diagnosing pediatric bipolar disorder is challenging due to the range of symptom expression, developmental differences as compared to adults, presence of comorbid disorders, and developing diagnostic criteria. Treating this disorder can be equally challenging due to frequent symptom relapse and the dearth of research until recently on effective psychopharmacological interventions that guide clinical prescribing practices.

PURPOSE:  This paper will help child psychiatric nurses have a better understanding of the unique presentation of pediatric bipolar disorder to facilitate selection of appropriate medication treatment options, taking into account symptom presentation, presence of comorbid diagnosis, drug efficacy, adverse effects, and drug–drug interactions based on research findings.

SOURCES:  Literature specific to assessment and psychopharmacological treatment of pediatric bipolar disorder was reviewed.

CONCLUSIONS:  Screening of youth with mood spectrum problems for bipolar disorder should occur in every diagnostic assessment and should be ongoing due to range of mood symptoms and the cyclical and episodic nature of this disorder. Youth with bipolar disorder may manifest symptoms and course that differ from adults. Additionally, co‐occuring disorders are common in this population, which can complicate medication selection. Psychopharmacological treatment with the use of specific mood stabilizers and/or atypical antipsychotic medications is warranted depending on symptom presentation; however, monotherapy with mood stabilizers has not demonstrated effectiveness in long‐term remission of pediatric bipolar symptoms. Recent research indicates that a combined treatment with two mood stabilizers or a mood stabilizer and an antipsychotic holds promising results for pediatric bipolar I, for youth with acute manic symptoms plus psychosis, and for long‐term remission of symptoms.
Modeling of field-assisted emission from a negative electron affinity cathode
Authors: Mayer A. , Chung M. S. , Kumar N. , Weiss B. L. , Miskovsky N. M. , Cutler P. H.
Published: February 2007

A device has been reported recently [M. W. Geis et al., Appl. Phys. Lett. 87, 192115 (2005)] in which electrons transit through the image states of a negative electron affinity glass substrate before being emitted to the vacuum. The external field required for this emission may be as low as 10V∕cm, which is up to three orders of magnitude lower than the fields encountered with other materials and configurations. The authors present a description and analysis of this device, which includes the glass substrate and the metallic contacts. The model also accounts for the ionization of cesium in the glass. Two stages are considered: (i) the activation step in which a 200V bias is established through the glass and (ii) the operational state in which the transfer of electrons from the metallic contacts to the glass surface is enhanced by positive ions trapped in the glass. The results provide insight into the role of the positive charges trapped in the glass. It is shown that the conditions are encountered, both in the activation step of the device and in its subsequent unbiased working mode, to account for the emission reported experimentally.
MULTI-SOLITON PROPAGATION IN AN INHOMOGENEOUS OPTIC FIBER MEDIUM WITH VARYING DISPERSION
Authors: SUBHA P. A. , KURIAKOSE V. C.
Published: February 2007

Multi-soliton propagation in an inhomogeneous optic fiber medium with frequency chirping has been analyzed in this paper. The two-soliton solution for the nonlinear Schrodinger equation within the integrable limit has been constructed using Backlund transformation technique and a recursive method. As the multi-soliton propagates through the inhomogeneous fiber, the traveling pulse gets compressed and amplified, which supports multi-soliton pulse compression technique. The inhomogeneous optic fiber system for varying GVD parameters has also been studied using variational analysis and numerical methods. As the pulse propagates through the inhomogeneous optic fiber, its width decreases and amplitude increases, which is similar to the case of adiabatic compression of solitons.
Money, Mission, or Match
Authors: Robertson Peter J. , Lo Carlos Wing-Hung , Tang Shui-Yan
Published: February 2007

This study explores antecedents of commitment among 1,300 municipal employees in three Chinese cities. Six potential antecedents, drawn from the rational choice and organizational behavior literatures, are investigated. Regression analysis indicates that role fit is the most important antecedent, followed by job challenge and management support. Extrinsic rewards and shared belief in the organization’s mission and values are not as strongly or consistently related to commitment level. Compatible with findings from studies in Western countries, the results suggest that commitment among Chinese public employees may depend on the extent to which they experience their organization as being committed to them.
Synthesis and Characterization of Al(OH)3-Y(OH)3-ZrB2 Composite Particles
Authors: Song Jie-Guang , Zhang Lian-Meng , Li Jun-Guo , Song Jian-Rong
Published: February 2007

In order to decrease the oxidization and improve the strength of ZrB2 at high temperature, the surface of ZrB2 was coated with Al(OH)3 and Y(OH)3 to synthesize Al(OH)3-Y(OH)3-ZrB2 composite particles. Through TEM, EPMA and SEM analysis, when pH was about 9, Al(OH)3-Y(OH)3-ZrB2 composite particles were successfully synthesized by co-precipitation methods. The coating layer was about 25 nm, which has compaction and conformability. Dispersibility of coated ZrB2 with Al(OH)3 and Y(OH)3 particles were very good. Synthesis of Al(OH)3-Y(OH)3-ZrB2 composite powder will lay the foundation for preparing high-performance YAG/ZrB2 and Al2O3-YAG/ZrB2 multiphase ceramic materials.
CLLU1 expression analysis adds prognostic information to risk prediction in chronic lymphocytic leukemia
Authors: Josefsson Pär , Geisler Christian H. , Leffers Henrik , Petersen Jørgen H. , Andersen Mette K. , Jurlander Jesper , Buhl Anne Mette
Published: February 2007

We recently identified a disease-specific gene CLLU1 in chronic lymphocytic leukemia (CLL) and also demonstrated that high CLLU1 expression levels predict poor clinical outcome. To validate this finding, we measured CLLU1 mRNA expression levels by real-time reverse transcriptase–polymerase chain reaction (RT-PCR) in 175 patients with CLL. Analyses of IgVH mutational status, ZAP-70 expression, CD38 expression, and chromosomal aberrations were also performed. High levels of CLLU1 expression were associated with shorter overall survival (P < .001), with a 7% increase in risk of early death by each doubling of the CLLU1 expression level. Stratification for age at diagnosis demonstrated a strong prognostic significance of CLLU1 expression in patients younger than 70 years (P < .001), but not in patients aged 70 or older (P = .61). The prognostic significance of IgVH mutational status and ZAP-70 expression had a similar age-dependent variation. Multivariate analysis in the younger age group showed that CLLU1 expression analysis added further prognostic information within all prognostic subgroups, with the exception of patients with unmutated IgVH CLL. Only CLLU1 expression and IgVH mutational status had independent predictive power. Thus, analysis of CLLU1 expression is highly applicable in risk prediction in CLL for patients of an age eligible for risk stratification.
The nature of structure-bonded H2O in illite and leucophyllite from dehydration and dehydroxylation experiments
Authors: Drits Victor A. , McCarty Douglas K.
Published: February 2007

Thermogravimetric analysis combined with mass spectrometry was used to study H2O bound to samples of illite-1M, illite-2M2and leucophyllite-1M. Samples were heated in a helium atmosphere at different temperatures and after heating at each given temperature were cooled to 35°C. Each cycle in the mass 18 spectrum of each illite sample contains a low-temperature peak at 60–80°C, a medium-temperature peak at 340–360°C, and a high-temperature peak at a temperature that is very close to the maximum temperature of sample heating of a given cycle. Within each heating-cooling cycle, the sample weight at the beginning of cooling is lower than that at the end of the same cooling stage because of H2O resorption. However, the number of H2O molecules released during each medium-temperature heating cycle is equal to the number of H2O molecules resorbed during the corresponding cooling stages.

The weight losses, under medium-temperature heating, of the illite samples are related to dehydration when H2O molecules located in K-free sites of the illite interlayers are removed. The medium-temperature peak is reproducible for each cycle because during each cooling stage the illite interlayers resorb the same number of H2O molecules that were lost during the preceding dehydration.

Two distinct features are characteristic of leucophyllite during heating-cooling treatments. First, the number of H2O molecules resorbed during cooling is significantly greater than the number of H2O molecules lost during dehydration. Second, the medium-temperature peaks in the spectrum appear only in the last five cycles and the maximum-peak temperature is 450–460°C. These data indicate that the heating-cooling treatments are accompanied by partial rehydroxylation. This rehydroxylation occurs during each coolingstage when a small number of resorbed H2O molecules are trapped in the interlayers, although most migrate into the octahedral sheet of the 2:1 layers and reform as OH groups. The crystal chemical factors responsible for the dehydration and rehydration as well as for the rehydroxylation reactions are discussed and speculation about the origin of the low- and medium-temperature H2O losses is presented.
Beliefs and Practices of Itinerant Teachers of Deaf and Hard of Hearing Children Concerning Literacy Development
Authors: Reed Susanne
Published: February 2007

A qualitative case study examined beliefs and practices of itinerant
teachers of deaf and hard of hearing students concerning literacy
development, the match between these teachers' beliefs and practices,
and the impact of itinerant settings. Five itinerant teachers and 15
students participated. Hearing losses were mild to profound. The research
addressed 5 areas: sociocultural aspects of literacy development; effects
of hearing loss on literacy development; beliefs about teaching and
literacy development; practices used to develop literacy; the impact of
itinerant settings on literacy development of deaf and hard of hearing
learners. Five themes emerged from the data: Itinerant teachers used
a variety of practices to develop literacy; itinerant teachers played
a supporting role in developing literacy; most of the teachers' beliefs
about literacy development were matched in their practices; the itinerant
teachers were lifelong learners; the impact of itinerant settings on
literacy development took many forms.
Functional equations and uniformity for local zeta functions of nilpotent groups
Authors: du Sautoy Marcus P. F. , Lubotzky Alexander
Published: February 2007

We investigate in this paper the zeta function [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="01i"/] associated to a nilpotent group Γ introduced in [GSS]. This zeta function counts the subgroups H ≤ Γ whose profinite completion Ĥ is isomorphic to the profinite completion [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="02i"/]. By representing [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="03i"/] as an integral with respect to the Haar measure on the algebraic automorphism group G of the Lie algebra associated to Γ and by generalizing some recent work of Igusa [I], we give, under some assumptions on Γ, an explicit finite form for [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="04i"/] in terms of the combinatorial data of the root system of G and information about the weights of various representations of G . As a corollary of this finite form we are able to prove (1) a certain uniformity in p confirming a question raised in [GSS]; and (2) a functional equation that the local factors satisfy [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="05i"/]. This functional equation is perhaps the most important result of the paper as it is a new feature of the theory of zeta functions of groups.
Stability of stationary interfaces with contact angle in a generalized mean curvature flow
Authors: Ei S.-I. , Sato M.-H. , Yanagida E.
Published: February 2007

The dynamics of a moving hypersurface in a domain D ⊂ R N is studied. It is assumed that the hypersurface moves depending on its curvature, normal vector and position with the boundary that intersects ∂ D with a constant contact angle. A stability criterion about a stationary hypersurface is established in the form of an eigenvalue problem, which includes geometrical information of ∂ D and the stationary hypersurface.
On Guan's examples of simply connected non-Kahler compact complex manifolds
Authors: Bogomolov Fedor A.
Published: February 2007

The article contains a construction of compact complex symplectic manifolds which are simply connected and don't admit Kahler structure. The manifolds obtained are essentially the same as were constructed by Guan, but the construction itself is geometrically more transparent.
Adams operations and integral Hermitian-Galois representations
Authors: Burns D. , Chinburg T.
Published: February 2007

We give an algebraic interpretation of the action of the j -th Adams operator j on Hermitian Galois structure classes for tame covers of schemes of dimension 1 . This generalizes work of Erez and of Erez-Taylor concerning rings of algebraic integers when j = 2 .
Delayed singularity formation in 2D compressible flow
Authors: Sideris Thomas C.
Published: February 2007

The initial value problem for the compressible Euler equations in two space dimensions is studied. Of interest is the lifespan of classical solutions with initial data that is a small perturbation from a constant state. The approach taken is to regard the compressible solution as a nonlinear superposition of an underlying incompressible flow and an irrotational compressible flow. This viewpoint yields an improvement for the lifespan over that given by standard existence theory. The estimate for the lifespan is further improved when the initial data possesses certain symmetry. In the case of rotational symmetry, a result of S. Alinhac is reconsidered. The approach is also applied to the study of the incompressible limit. The analysis combines energy and decay estimates based on vector fields related to the natural invariance of the equations.
On certain distinguished unitary representations supported on null cones
Authors: Tan Eng-Chye , Zhu Chen-Bo
Published: February 2007

Let [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="01i" /] = [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="02i" /] or [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="03i" /], and let G = U ( p, q ; [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="04i" /]) be the isometry group of a [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="05i" /]-hermitian form of signature ( p, q ). For 2 n ≤ min ( p, q ), we consider the action of G on V n , the direct sum of n copies of the standard module V = [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="06i" /], and the associated action of G on the regular part of the null cone, denoted by X 00 . We show that there is a commuting set of G -invariant differential operators acting on the space of C ∞ functions on X 00 which transform according to a distinguished GL ( n , [inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="07i" /]) character, and the resulting kernel is an irreducible unitary representation of G . Our result can be interpreted as providing a geometric construction of the theta lift of the characters from the group G ' = U ( n, n ) or O * (4 n ). The construction and approach here follow a previous work of Zhu and Huang [ Representation Theory 1 (1997)] where the group concerned is G = O ( p, q ) with p + q even.
Classification of simple C *-algebras with unique traces
Authors: Lin Huaxin
Published: February 2007

We classify certain almost multiplicative morphisms up to approximate unitary equivalence and use this result to prove the following: Let A and B be two unital separable simple C *-algebras of real rank zero, stable rank one, with weakly unperforated K 0 -groups and with unique normalized quasi-traces. Suppose that both A and B are locally AH and ( K * ( A ), K * ( A ) + ,[1 A ]) ≅ ( K * ( B ), K * ( B ) + ,[1 B ]). Then A is isomorphic to B .
Finite local monodromy of overconvergent unit-root F-isocrystals on a curve
Authors: Tsuzuki Nobuo
Published: February 2007

We prove that the category of p -adic continuous representations of a fundamental group of a curve over a perfect field of a positive characteristic p with finite local monodromy is equivalent to that of overconvergent unit-root F -isocrystals on the curve. To show the equivalence of categories, we study the local theory and apply it to the global case.
On the Euler characteristic of generalized Kummer varieties
Authors: Debarre Olivier
Published: February 2007

We apply the Yau-Zaslow-Beauville method to compute the Euler characteristic of the generalized Kummer varieties attached to a complex abelian surface A (a calculation also done by Göttsche and Soergel by a different method). The argument is very geometric: given a nondivisible ample line bundle L of degree n on A , we construct a projective symplectic variety J with a Lagrangian fibration whose Euler characteristic is n times the number of genus 2 curves in | L |, to wit n 2 Σ m | n m . Using the Mukai-Fourier transform, a degeneration to the case when A is a product of elliptic curves and a result of Huybrechts, we prove that J and the generalized (2 n -2)-dimensional Kummer variety of A are diffeomorphic, hence have the same Euler characteristic.
Lower bounds for the minima of certain symplectic and unitary group lattices
Authors: Dummigan Neil , Tiep Pham Huu
Published: February 2007

We obtain lower bounds for the minimal norms in several families of integral lattices associated to the Weil representations of finite symplectic and unitary groups. Ultimately, these bounds come from Elkies' bounds for a certain family of Mordell-Weil lattices of elliptic curves, and from the minima of the Barnes-Wall lattices.
Semiconjugacies between Kleinian group actions on the Riemann sphere
Authors: Klarreich Erica
Published: February 2007

We consider the problem of characterizing topologically the action of a Kleinian group on the Riemann sphere Ĉ . We prove that certain geometrically infinite Kleinian group actions on Ĉ can be obtained from geometrically finite ones by a semiconjugacy that is determined by the end invariants of the geometrically infinite group. This turns out to be related to the problem of continuous extensions of maps of hyperbolic 3-space H 3 to maps of its boundary at infinity, Ĉ . Along the way we consider the general problem of extending maps to the boundary at infinity in Gromov-hyperbolic metric spaces. We give criteria for extending to the boundary a map h : X → Y between hyperbolic spaces if it extends to the boundary of certain subsets of X .
Effective bounds for the number of transcendental points on subvarieties of semi-abelian varieties
Authors: Hrushovski Ehud , Pillay Anand
Published: February 2007

Let A be a semi-abelian variety, and X a subvariety of A , both defined over a number field. Assume that X does not contain X 1 + X 2 for any positive-dimensional subvarieties X 1 , X 2 of A . Let Γ be a subgroup of A ( C ) of finite rational rank. We give doubly exponential bounds for the size of ( X ∩ Γ)\ X ( Ǭ ). Among the ingredients is a uniform bound, doubly exponential in the data, on finite sets which are quantifier-free definable in differentially closed fields. We also give uniform bounds on X ∩ Γ in the case where X contains no translate of any semi-abelian subvariety of A and Γ is a subgroup of A ( C ) of finite rational rank which has trivial intersection with A ( Ǭ ). (Here A is assumed to be defined over a number field, but X need not be.)
Non-simple purely infinite C *-algebras
Authors: Kirchberg Eberhard , Rørdam Mikael
Published: February 2007

A C *-algebra A is defined to be purely infinite if there are no characters on A , and if for every pair of positive elements a, b in A , such that b lies in the closed two-sided ideal generated by a , there exists a sequence { r n } in A such that r * n ar n → b . This definition agrees with the usual definition by J. Cuntz when A is simple. It is shown that the property of being purely infinite is preserved under extensions, Morita equivalence, inductive limits, and it passes to quotients, and to hereditary sub- C *-algebras. It is shown that A ⊗ O ∞ is purely infinite for every C *-algebra A . Purely infinite C *-algebras admit no traces, and, conversely, an approximately divisible exact C *-algebra is purely infinite if it admits no nonzero trace.
Algebraic Gauss-Manin systems and Brieskorn modules
Authors: Dimca Alexandru , Saito Morihiko
Published: February 2007

We study the algebraic Gauss-Manin system and the algebraic Brieskorn module associated to a polynomial mapping with isolated singularities. Since the algebraic Gauss-Manin system does not contain any information on the cohomology of singular fibers, we first construct a nonquasi-coherent sheaf which gives the cohomology of every fiber. Then we study the algebraic Brieskorn module, and show that its position in the algebraic Gauss-Manin system is determined by a natural map to quotients of local analytic Gauss-Manin systems, and its pole part by the vanishing cycles at infinity, comparing it with the Deligne extension. This implies for example a formula for the determinant of periods. In the two-dimensional case we can describe the global structure of the algebraic Gauss-Manin system rather explicitly.
Harmonic maps between surfaces and Teichmüller spaces
Authors: Mese Chikako
Published: February 2007

We study harmonic maps between two distinct compact Riemann surfaces of the same genus. Our aim is to examine the role of the curvature in the relationship between energies of harmonic maps and conformal metrics on the target surface. We consider the energy of the energy minimizing map between the surfaces as a function of the metrics within the conformal class of the target and solve the variational problem of minimizing this functional when we restrict the upper curvature bound and normalize the area of the metrics. In doing so, we show that the upper curvature bound on the normalized target metric is an obstruction in obtaining a degree 1 conformal harmonic map between distinct Riemann surfaces.
Birkhoff normal forms for Fourier integral operators II
Authors: Iantchenko A. , Sjöstrand J.
Published: February 2007

In this work we construct logarithms and Birkhoff normal forms for elliptic Fourier integral operators in the semi-classical limit, under more general assumptions than in a previous work by the first author. The methods are similar but slightly different.
A criterion for the equivalence of formal singularities
Authors: Möhring Konrad , van Straten Duco
Published: February 2007

We prove a generalization of the finite determinacy theorem for isolated singularities. The maximal ideal occuring in the finite determinacy theorem is replaced by any ideal annihilating the first cotangent cohomology of a formal singularity over a Noetherian ring. An analogous result holds for finitely generated modules. As an application we give a criterion for the algebraizability of formal singularities and modules.
Non-Archimedean holomorphic maps and the Ahlfors islands theorem
Authors: Benedetto Robert L.
Published: February 2007

We present a p -adic and non-archimedean version of some classical complex holomorphic function theory. Our main result is an analogue of the Five Islands Theorem from Ahlfors' theory of covering surfaces. For non-archimedean holomorphic maps, our theorem requires only two islands, with explicit and nearly sharp constants, as opposed to the three islands without explicit constants in the complex holomorphic theory. We also present non-archimedean analogues of other results from the complex theory, including theorems of Koebe, Bloch, and Landau, with sharp constants.
On the nef cone of symmetric products of a generic curve
Authors: Pacienza Gianluca
Published: February 2007

The nef cone of the symmetric product C ( k ) of a curve C with general moduli is easily determined when k is at least equal to the gonality gon ( C ) of the curve. In this paper we describe the nef cone for k = gon ( C ) - 1, when the genus of C is even. In this case the boundary of the nef cone has rational slope and is determined using curves on C ( k ) associated to the g 1 k +1 's of C .
Dimensions of jet schemes of log singularities
Authors: Yasuda Takehiko
Published: February 2007

We characterize Kawamata log terminal singularities and log canonical singularities by dimensions of jet schemes. Our main result is Theorem 2.4.
Girls with Guns: Narrating the Experience of War of Frelimo's "Female Detachment"
Authors: West Harry G.
Published: February 2007

This article examines the way in which female guerrillas both appropriated and contributed to the FRELIMO narrative of women's participation in the struggle for Mozambican liberation. The author argues that ideological commitment to the cause was essential to defining the experience of violence for these girls and young women and that, concurrent with their convictions, they felt empowered rather than victimized by the war. The article contributes to an emerging literature suggesting that the culturally-specific meanings given to the social category of youth as well as to experiences of violence are essential to understanding the impact upon Africa's youth of the continent's many armed conflicts.
Fistfights at the Moscow Choral Synagogue: Ethnicity and Ritual in Post-Soviet Russia
Authors: Goluboff Sascha L.
Published: February 2007

In this article I investigate ritual life at the Moscow Choral Synagogue, the largest and longest running Orthodox synagogue in the Russian capital. Unlike many Eastern European synagogues, this synagogue is a thriving prayer community due to its unique congregation of Russian, Georgian, Bukharan, Mountain, and visiting Western Jews. I focus on a fistfight that took place between an Israeli and a Georgian Jew during prayer. I detail how Russian and Georgian Jews interpreted the incident to be a result of their different ethnicities, Russian and Georgian respectively. The fight elucidates how ritual in post-Soviet society provides the means for the production of ethnicity and Jewish identity. Arguing for localism within Judaism's transnational ideology, I suggest that Jewish identity, like ritual, is performative and contextual. I also show how the shifting power relations in post-Soviet society have reshaped ethnicity, making state-endorsed market reform a reference point of ethnic differentiation.
Encounters with the Super-Citizen: Neoliberalism, Environmental Activism, and the American Heritage Rivers Initiative
Authors: Guldbrandsen Thaddeus Countway , Holland Dorothy C.
Published: February 2007

In this article we argue that while new kinds of political activism are flourishing in local areas, increasing partnership with economic development interests poses serious challenges to the political efficacy of environmental activism. We examine the shifting terrain of local political activism within the context of the American Heritage Rivers Initiative, a new federal program designed to facilitate environmental preservation, economic development, and cultural preservation along U.S. rivers. This article is based on research done along the New River in North Carolina and Virginia with a collection of local groups organized into a regional partnership. That partnership exemplifies emerging forms of local political action under new regimes of state power and hybrid partnerships. We argue that if hybrid forms of environmental activism spread, with their emphasis on neoliberalism and ecological modernization, they will likely pose challenges for grassroots politics and, as has been the case along the New River, blunt the critical edge of the environmental critique.