bluuebunny/crossref_metadata_2025 huggingface dataset:
Conflict resolution patterns and longevity of adolescent romantic couples: A 2‐year follow‐up study
Authors: Shulman Shmuel , Tuval‐Mashiach Rivka , Levran Elisheva , Anbar Shmuel
Published: September 2005

This study examined the predictors of longevity among 40 late adolescent romantic couples (mean age males=17.71 years; mean age females=17.18 years). Subjects were given a revealed differences task where they were asked to solve their disagreements. The joint task was recorded, transcribed and analysed by two raters. At 3, 6, 9, 12, 18, and 24 months after this procedure, partners were contacted by telephone and asked whether their relationship was still intact. A cluster analysis was performed on couples’ interaction indices and yielded three distinctive conflict resolution patterns. TheDownplayingpattern was characterized by a high tendency to minimize the conflict. The relationships of the adolescents displaying this pattern stayed intact for a period of 9 months. Half of them were still together after 24 months. Theadolescents displaying the Integrativepattern, which shows a good ability to negotiate differences tended to stay together over a period of 24 months. Those showing theConflictivepattern, characterized by a confrontative interaction, were separated by the 3 months follow‐up. Results are discussed within the context of developmental perspectives of conflict resolution tendencies and adolescent romance.
Dicing and slicing
Authors: Hammond Scott M.
Published: September 2005

RNA interference (RNAi) is broadly defined as a gene silencing pathway that is triggered by double‐stranded RNA (dsRNA). Many variations have been described on this theme. The dsRNA trigger can be supplied exogenously, as an experimental tool, or can derive from the genome in the form of microRNAs. Gene silencing can be the result of nucleolytic degradation of the mRNA, or by translational suppression. At the heart of the pathway are two ribonuclease machines. The ribonuclease III enzyme Dicer initiates the RNAi pathway by generating the active short interfering RNA trigger. Silencing is effected by the RNA‐induced silencing complex and its RNaseH core enzyme Argonaute. This review describes the discovery of these machines and discusses future lines of work on this amazing biochemical pathway.
Identification of plasma membrane associated mature β‐hexosaminidase A, active towards GM2 ganglioside, in human fibroblasts
Authors: Mencarelli Simona , Cavalieri Cristina , Magini Alessandro , Tancini Brunella , Basso Luisa , Lemansky Peter , Hasilik Andrej , Li Yu-Teh , Chigorno Vanna , Orlacchio Aldo , Emiliani Carla , Sonnino Sandro
Published: September 2005

Mature β‐hexosaminidase A has been found associated to the external leaflet of plasma membrane of cultured fibroblasts. The plasma membrane association of β‐hexosaminidase A has been directly determined by cell surface biotinylation followed by affinity chromatography purification of the biotinylated proteins, and by immunocytochemistry. The immunological and biochemical characterization of biotinylated β‐hexosaminidase A revealed that the plasma membrane associated enzyme is fully processed, suggesting its lysosomal origin.
A single glutamine synthetase gene produces tissue‐specific subcellular localization by alternative splicing
Authors: Matthews Gideon D. , Gould Robert M. , Vardimon Lily
Published: September 2005

Glutamine synthetase (GS) plays a key role in two major biochemical pathways: In liver GS catalyzes ammonia detoxification, whereas in neural tissues it also functions in recycling of the neurotransmitter glutamate. In most species the GS gene gives rise to a cytoplasmic protein in both liver and neural tissues. However, in species that utilize the ureosmotic or uricotelic system for ammonia detoxification, the enzyme is cytoplasmic in neural tissues, but mitochondrial in liver cells. Since most vertebrates have a single copy of the GS gene, it is not clear how tissue‐specific subcellular localization is achieved. Here we show that in the ureosmotic elasmobranch, Squalus acanthias (spiny dogfish), two different GS transcripts are generated by tissue‐specific alternative splicing. The liver transcript contains an alternative exon that is not present in the neural one. This exon leads to acquisition of an upstream in‐frame start codon and formation of a mitochondrial targeting signal (MTS). Therefore, the liver product is targeted to the mitochondria while the neural one is retained in the cytoplasm. These findings present a mechanism in which alternative splicing of an MTS‐encoding exon is used to generate tissue‐specific subcellular localization.
Identification and analysis of Hic‐5/ARA55 isoforms: Implications for integrin signaling and steroid hormone action
Authors: Gao Zhengliang , Schwartz Lawrence M.
Published: September 2005

Hic‐5/ARA55 is a LIM‐only member of the paxillin superfamily. Conflicting reports have suggested that Hic‐5/ARA55 can both repress and enhance a number of biological processes, including myogenesis and tumorigenesis. With two Hic‐5 isoforms documented, we hypothesized that multiple Hic‐5 isoforms may exist that have both overlapping and isoform‐specific functions. To test this hypothesis, we performed an extensive analysis of Hic‐5 transcripts in both cell lines and mouse tissues and found 12 distinct isoforms that fall into two sub‐families. These isoforms are derived from both alternative splicing and alternative transcriptional start sites (TSS). Hic‐5 expression is regulated in a temporally and spatially controlled manner in vivo. The identification of numerous Hic‐5 isoforms suggests that Hic‐5 subsumes a number of distinct roles in cells and may explain the range of biological responses attributed to Hic‐5.
RACK1 mRNA translation is regulated via a rapamycin‐sensitive pathway and coordinated with ribosomal protein synthesis
Authors: Loreni Fabrizio , Iadevaia Valentina , Tino Elisa , Caldarola Sara , Amaldi Francesco
Published: September 2005

RACK1 has been shown to interact with several proteins, this suggesting that it may play a central role in cell growth regulation. Some recent articles have described RACK1 as a component of the small ribosomal subunit. To investigate the relationship between RACK1 and ribosome, we analyzed RACK1 mRNA structure and regulation. Translational regulation was studied in HeLa cells subjected to serum or amino acid deprivation and stimulation. The results show that RACK1 mRNA has a 5′ terminal oligopyrimidine sequence and that its translation is dependent on the availability of serum and amino acids in exactly the same way as any other vertebrate ribosomal protein mRNA.
The Mawzaע Exile at the Juncture of Zaydi and Ottoman Messianism
Authors: Hathaway Jane
Published: September 2005

Among scholars of Jewish communities under Islamic rule, Yemen has gained a poor reputation for treatment of its ancient Jewish minority in comparison with other predominantly Muslim societies. Although Yemen had, until the 1950s, a sizable Jewish population whose presence dated back centuries before the advent of Islam, various Muslim rulers of key parts of Yemen enforced the sumptuary laws and other restrictions stipulated in the Pact of עUmar with unusual stringency, and the Jews' history under Islamic rule was marred by sporadic instances of outright persecution.
Restitution of Lost Property in the Tannaitic and Amoraic Halakhah: A Preliminary Philosophical Study of the Forming of a Conception
Authors: Furstenberg Ariel
Published: September 2005

This paper explores the development of a particular talmudic halakhic theme—the restitution of lost property—through the philosophical prism of Hilary Putnam's distinction between concepts and conceptions. This distinction holds that one can affirm a set of concepts without commitment to the underlying conceptions from which they are drawn. The focus here is upon substantial discrepancies between tannaitic and amoraic authorities in the presentation of the halakhot of restitution of lost property. These discrepancies testify to a significant change in the underlying conceptual framework of tannaitic and amoraic halakhic thinking on this topic.
Yair Lorberbaum. Image of God, Halakhah and Aggadah. Tel Aviv: Schocken Publishing House, 2004. 544 pp.
Authors: Kulp Joshua
Published: September 2005

The central thesis of Lorberbaum's book is that according to the rabbis, the meaning of imago dei is that there is tangible divine presence within every human being. This concept impacted primarily upon two areas of halakhah: the death penalty and procreation. Since humans are physical representations of God, execution is equivalent in some ways to deicide. Conversely, procreation is strongly mandated because it increases God's physical manifestation in the world by creating more vehicles in which to embody God's presence. Importantly, as “images” of the divine, human beings function as icons in a manner similar to the way idols function in the pagan world; they draw God's presence into themselves, blurring the borders between representation and form. Finally, the drawing of God's presence into the human body dictates that human beings are embodied with significant theurgic powers.
Aaron W. Hughes. The Texture of the Divine: Imagination in Medieval Islamic and Jewish Thought. Bloomington: Indiana University Press, 2004. x, 273 pp.
Authors: Bland Kalman P.
Published: September 2005

Three texts are scrutinized in this monograph: Hayy ibn Yaqzan (Alive son of Awake), the Epistle or philosophic “Recital” composed in Arabic prose by the Muslim sage ibn Sina (Avicenna, 980–1037); Hayy ben Meqitz, the closely related Hebrew poem composed by the Andalusian Jewish sage Abraham ibn Ezra (1089–1164); and Hayy ibn Yaqzan, the more loosely related Arabic treatise composed by the Andalusian Muslim sage Abu Bakr ibn Tufayl (1116–1185). Each of the texts is well known to specialists in medieval intellectual history. Editions and critical discussions abound, almost all of them listed in the bibliography (pp. 245-65). The Arabic texts have long been accessible in reliable English translations. Thanks to Aaron W. Hughes, the same can now be said for ibn Ezra's less familiar narrative poem. In the appendix (pp. 189–207), the poem is rendered into English based on the original Hebrew text published in 1983 by Israel Levin. The translation is enhanced by references to the biblical idioms employed by ibn Ezra who ingeniously transformed ibn Sina's profoundly Islamic original into an equally stunning Hebrew gem.
Dean Phillip Bell. Sacred Communities: Jewish and Christian Identities in Fifteenth-Century Germany. Studies in Central European Histories. Leiden: Brill, 2001. xii, 301 pp.
Authors: Carlebach Elisheva
Published: September 2005

German Jewish communities underwent momentous changes in status, composition, and character during the fifteenth century, yet apart from its intellectual legacy, this period has merited scant attention from historians. Even contemporaries viewed the post-plague German communities as a diminished and spent shadow of their vital medieval Ashkenazic predecessors, and historiography has maintained this perception. Scholars characterized the period as one of intellectual decline, population shrinkage and expulsion from the remaining cities that had not destroyed or expelled their Jewish communities during the bubonic plague depredations. Despite the real devastation caused by the fourteenth-century chaos, much vibrant life remained within German Jewish communities. Little has been written, particularly in English, concerning the reasons for subsequent Christian resistance to the presence of Jews and the effects of new Christian conceptions of their own communities on Jewish self-perception. Bell's book intends to fill this gap. Neither a social history, nor an intellectual history of fifteenth-century Germans and Jews, it is a pioneering attempt to track the changing definitions of Jewish and Christian identity in the fifteenth century. It is an ambitious enterprise.
Marcia Reynders Ristaino. Port of Last Resort: The Diaspora Communities of Shanghai. Stanford: Stanford University Press, 2001. xxxi, 369 pp.
Authors: Wasserstein Bernard
Published: September 2005

This book compares two uneasily related exile communities in early twentieth-century Shanghai: the Russians and the Jews. Although traders, including some Jews, had drifted down from Siberia from the mid-nineteenth century, the Russians in Shanghai, for a time the city's largest foreign community, were mainly remnants of Admiral Kolchak's “White” army who fled Vladivostok in 1922–23, with a rag-tag group of camp followers, aboard what remained of the former imperial fleet. Most settled in the French Concession district and worked as small shopkeepers. The Jewish refugees from Germany and Central Europe who followed in the period 1938–41 had little in common with the Russians, some of whom regarded the Jews as commercial rivals, and many of whom were deeply infected by the traditional anti-Semitism of the Russian extreme right.
Joshua D. Zimmerman. Poles, Jews, and the Politics of Nationality: The Bund and the Polish Socialist Party in Late Tsarist Russia, 1892–1914. Madison: University of Wisconsin Press, 2004. xiii, 360 pp.
Authors: Weeks Theodore R.
Published: September 2005

For a half-millennium until the 1940s, the history of Poles and Jews was inextricably intertwined. In particular, from the mid-nineteenth century onwards, Poles and Jews alike were faced with sweeping economic and social changes that challenged—even threatened—livelihood, traditions, and identity. One way in which both Jews and Poles attempted to make sense of “modernity” (to use the word as shorthand for industrialization, secularization, and the communications revolution of this period) was to subscribe to one or another form of socialism. In the Polish lands, socialism and nationalism were never mutually exclusive, indeed on the whole, the two movements overlapped considerably. Again, this was just as true for Jews (Bund, Poalei Tsiyon) as for Poles (PPS). Josh Zimmerman's important book examines relations between the two most important pre-1914 Polish and Jewish socialist parties, the Bund and the PPS. Both parties aimed simultaneously to pave the way for international socialism and to develop their respective nations (Jews and Poles). Both parties rejected national chauvinism or prejudice, arguing in a Herderian vein that only when each nation developed its full potential could true internationalism reign. Despite their theoretical agreement, however, the parties frequently clashed on practical issues. Examining these practical differences, Zimmerman has much to tell us about the nature of being Jewish, Polish, and/or socialist in late imperial Russia.
Waterborne epidemic outbreak of Shigella sonnei gastroenteritis in Santa Maria de Palautordera, Catalonia, Spain
Authors: ARIAS C. , SALA M. R. , DOMÍNGUEZ A. , BARTOLOMÉ R. , BENAVENTE A. , VECIANA P. , PEDROL A. , HOYO G.
Published: September 2005

In August 2002 an outbreak of Shigella sonnei infection occurred in a Spanish town of 6343 inhabitants. In total, 756 people developed acute gastroenteritis and 181 cases were shigella-confirmed. The peak incidence was during 5–6 August 2002. The estimated primary attack rate was 9·97%; the attack rate for secondary cases was 38%. The <15 years ago group was most affected (16·49%). The town and its surroundings were served by two water systems, A and B. The cases had consumed water provided by system A (attack rate 164 cases/1000 population). Microbiological analysis of water from system A did not show the presence of coliform bacteria or shigella. This shigellosis outbreak was the largest reported in Spain. The impact of the epidemic was probably greater than the incidence detected.
Prevalence of Helicobacter pylori in United States Navy submarine crews
Authors: JACKMAN R. P. , SCHLICHTING C. , CARR W. , DUBOIS A.
Published: September 2005

Helicobacter pylori prevalence is elevated in German submarine crews and in United States Navy (USN) surface fleet personnel, but H. pylori prevalence in USN submariners was unknown. The goal of the study was to determine the prevalence of H. pylori in the crews of USN nuclear submarines compared to other military personnel and to the general US population. The presence of H. pylori IgG antibodies was determined in serum samples using a commercial ELISA. Only 47 out of 451 submariners (9·4%) were H. pylori positive, which is similar to that of the US general population with a similar level of education. In contrast, H. pylori prevalence is significantly higher in US Army recruits (26%), USN surface fleet personnel (25%), and German diesel submariners (38%). These data demonstrate that submarine service (and by inference activity requiring isolation and close contact, per se) is not a risk factor for H. pylori infection.
The increasing prominence of household transmission of hepatitis A in an area undergoing a shift in endemicity
Authors: VICTOR J. C. , SURDINA T. Y. , SULEIMEOVA S. Z. , FAVOROV M. O. , BELL B. P. , MONTO A. S.
Published: September 2005

In the rapidly developing city of Almaty, Kazakhstan, rates of hepatitis A have fallen, but no data on prevalence of antibody to hepatitis A virus (anti-HAV) exist with which to interpret incidence data. In the autumn of 2001, we determined the anti-HAV prevalence among household and school contacts of hepatitis A cases. For contacts aged 0–4 years, 5–9 years, 10–14 years, 15–19 years, or 20–30 years, immune prevalences were 9, 12, 33, 33 and 77% respectively, among immediate-family household contacts and 15, 28, 49, 52 and 77% respectively, among community contacts. Child community contacts were more likely to be immune than their immediate-family household counterparts (odds ratio 2·0, 95% confidence interval 1·3–3·2). Almaty is experiencing an epidemiological shift in hepatitis A incidence. Feasible and effective prevention strategies using hepatitis A vaccine should be explored.
the european commission and the law-making process: compromise as a category of praxis
Authors: sideri katerina
Published: September 2005

understanding law-making requires coming to grips with cognitive schemas, practical wisdom of agents involved in the production of law, as agents may interpret or apply the law according to socially accepted mental schemas developed as a result of socialisation in families, schools, universities and other social settings or in the course of exchange in professional settings. a case study on the conduct of officials of the european commission seeks to illustrate this point. this looks at tacit understandings regulating the conduct of officials of the european commission, engaging in the production of a legal proposal or in the implementation of a legal measure. such interaction may be successful, or less successful, depending on how contentious a legal file is, but is underlined by certain understandings, particular norms of conduct, as to how things are get done. in uncovering shared understandings, the article looks at modes of co-operation in working parties and shared files, promotion procedures, mobility, and how reputation is valued and acquired. the thesis advanced is of important cognitive schema, anthropological category of praxis, regulating the law-making process inside the european commission is compromise.
death rites: assisted suicide and existential rights
Authors: williams melanie l.
Published: September 2005

modern life presents us with new, as well as perennial perspectives upon death. this essay explores how we might articulate an apposite conception of rights in relation to death, in a time of a declared respect for individual autonomy and waning adherence to religious belief, and considers these questions with particular reference to the challenges to law and state made by dianne pretty in the months leading up to her death. to such an applicant, with a ‘lay’ experience and apprehension of the role and meaning of law, the prognostications of the court regarding the status of the claim must have seemed surreal indeed – especially where disputable, patchwork value-systems are called upon to lend authority to the decision. the essay concludes that such peregrinations have implications not only for the individual claimant, but for the credibility of law and associated ethics and that the writings of existential philosophers on the subject of death can assist in modelling a more consistent, secular notion of ethics in relation to assisted suicide.
Prediction and understanding of the north‐south displacement of the heliospheric current sheet
Authors: Zhao X. P. , Hoeksema J. T. , Scherrer P. H.
Published: September 2005

On the basis of Wilcox Solar Observatory observations of the photospheric magnetic field and the potential field‐source surface model, we compare the solid angles occupied by the positive source surface field with that of the negative. We develop an algorithm to quantitatively estimate and understand the positive‐negative displacement of the heliospheric current sheet (HCS) about Sun's magnetic dipole equator and the north‐south displacement of the HCS about the heliographic equator. The north‐south HCS displacement predicted using the algorithm quantitatively agrees with that observed by Ulysses and Wind in 1994–1995. The predicted positive‐negative and north‐south HCS displacement for 362 Carrington rotations between 1976 and 2001 show that in addition to the two long southward HCS displacement intervals that are consistent with earlier observations and statistical results, there are several short north‐south HCS displacement intervals in the rising and early declining solar activity phases. All the positive‐negative HCS displacements about the Sun's magnetic dipole equator determined for the 25 years can be understood using the positive‐negative asymmetry in the characteristics of coronal holes or open field regions between two hemispheres, such as the area, field strength, or the outward expansion factor of the coronal holes. To understand the north‐south HCS displacement about the heliographic equator, the effect of the Sun's magnetic dipole tilt angle relative to the Sun's rotation axis must be taken into consideration as well.
Effect of the seasonal variations in the lower atmosphere on the altitude of the ionospheric main peak at Mars
Authors: Zou H. , Wang J.‐S. , Nielsen E.
Published: September 2005

The heights of the Martian ionospheric main electron density peak observed by the Mars Global Surveyor Radio Science experiment in the northern and southern high‐latitude regions (60°–90°) are investigated. The data sets for both hemispheres were obtained in the same narrow solar longitude interval (∼134°–146°). The subsolar height of the main peak derived from the southern hemisphere data is 7.7 ± 4.3 km lower than that derived from the northern hemisphere data. The southern and northern hemispheres are in opposite seasons. The seasonal variations of the neutral atmospheric density and its scale height in the lower atmosphere are found to be the dominant reasons for the reported difference. Further analysis shows that the neutral atmosphere density at the altitude 20 km had the strongest effect.
Comparison of acoustic and net sampling systems to determine patterns in zooplankton distribution
Authors: Sutor Malinda , Cowles Timothy J. , Peterson William T. , Lamb Jesse
Published: September 2005

An analysis was conducted of the strengths and limitations of acoustic methods to determine biomass and taxonomic distribution patterns over the Oregon continental shelf. Measurements of volume backscatter from two different acoustic instruments were compared with each other and with predicted volume backscatter calculated from a coincident net tow. Spatially and temporally coincident data were collected from a six‐frequency bioacoustic system (Tracor Acoustic Profiling System (TAPS)) and from a 1 m2 Multiple Opening Closing Net and Environmental Sensing System (MOCNESS). The combined net/acoustic tows were conducted over the Oregon continental shelf in August 2001, during both day and night. The TAPS was mounted on the upper frame of the MOCNESS and ensonified a volume of water directly in front of the net mouth. A four‐frequency echosounder (Hydroacoustic Technologies Inc. (HTI)) with downward looking transducers was towed off the port side of the ship during the MOCNESS/TAPS tows. Fine‐scale vertical distributions of zooplankton that were resolved acoustically were not apparent within the integrated depth strata of the individual MOCNESS net samples. The taxonomic and size composition of the zooplankton community had strong effects on volume backscatter (SV), although the magnitude of SV was not linearly related to zooplankton biomass. Predicted SV calculated from scattering models and the contents of the MOCNESS nets agreed best (sometimes within 5 dB) with measured SV from the TAPS at 420 and 700 kHz and measured SV at 420 kHz from the HTI.
How widespread were climate anomalies 8200 years ago?
Authors: Morrill Carrie , Jacobsen Robert M.
Published: September 2005

Documenting the spatial extent of the 8.2 ka event is essential for understanding the possible response of the climate system to a freshwater perturbation in the North Atlantic. In this research, we analyzed paleoclimate proxy records from 52 sites using a statistical test to detect anomalies associated with the 8.2 ka event. Our results show that this event occurred in many parts of the Northern Hemisphere extratropics and the tropics. Evidence from the tropics is more spotty, but detection rates are similar for the tropics and extratropics, suggesting that tropical evidence for the event will become stronger as more records are generated. There is also a particular need for new paleoclimate proxy records from Southern Hemisphere sites and/or with quantitative estimates of climate anomalies.
Seismoacoustic evidence for volcanic activity on the ultraslow‐spreading Gakkel Ridge, Arctic Ocean
Authors: Schlindwein Vera , Müller Christian , Jokat Wilfried
Published: September 2005

In 1999, a swarm of earthquakes and a lava flow signaled a volcanic eruption at the eastern end of Gakkel Ridge, the slowest spreading ridge worldwide. In summer 2001, the multidisciplinary Arctic Mid‐Ocean Ridge Expedition studied these ridge processes which are unusual at ultraslow spreading rates. As part of these studies, we examined the microearthquake activity of the ridge with seismological arrays on ice‐floes. Near the volcanic center (85°40′N 85°E) active in 1999, we recorded a remarkable swarm of 200 acoustic events. The signals consist of two to four explosive phases, representing the direct water wave and multiple reflections. We localized the acoustic source at the northern rim of the lava flow of 1999. By comparison with similar signals produced at the ocean entry of the Kilauea lava, we postulate that we made an exceptional observation of the sounds of active submarine volcanism.
Comparison of large‐scale field‐aligned currents under sunlit and dark ionospheric conditions
Authors: Ohtani S. , Ueno G. , Higuchi T.
Published: September 2005

The present study statistically compares large‐scale field‐aligned currents (FACs) under sunlit and dark ionospheric conditions. A total of ∼74,000 auroral oval crossings are selected from magnetic field measurements from the DMSP F7 and F12 to F15 satellites. For the dayside FAC it is reconfirmed that both current intensity and density are statistically larger in the illuminated events than in the unilluminated events. As for the nightside FAC, in contrast, a few important features become clear for the first time, which can be summarized as follows: (1) At 20 ≤ MLT < 02 both R1 and R2 intensities tend to be larger when the ionosphere is dark than when it is sunlit. (2) Although dependence on the ionospheric condition is less clear for the FAC density, a systematic preference of the occurrence of strong FACs for the dark ionosphere can be found for both R1 and R2 currents in the dusk‐to‐premidnight (16 ≤ MLT < 22) sector and for the R1 current in the postmidnight sector (00 ≤ MLT < 02). (3) For both FAC intensity and density the difference between the illuminated and unilluminated events tends to increase with increasing geomagnetic activity as measured by the IMF BZ component. Result 1 can be partially explained in terms of the interhemispheric asymmetry of the magnetospheric configuration, which, however, should not affect the FAC density. Therefore result 2 strongly suggests that the solar‐induced conductivity controls the M‐I coupling in a different way in certain nightside MLT sectors than in dayside sectors.
Toward a global magnetospheric equilibrium model
Authors: Zaharia Sorin , Birn J. , Cheng C. Z.
Published: September 2005

In this paper we take a first step toward the development of a realistic global magnetospheric model in which the magnetic forces are equilibrated by plasma pressure forces. Such a model describes a “quasi‐static” equilibrium, a condition valid at most times in the Earth's magnetosphere. The work reported here involves the coupling in two dimensions of a numerical inner/middle magnetosphere model in flux coordinates, which solves the Grad‐Shafranov equation in “inverse” form, with an asymptotic magnetotail model farther away from Earth. We discuss the obtained configurations (including the resulting magnetic fields and electric currents) under different observation‐based inputs (parameters include plasma and total pressures, as well as the magnetic flux boundary). In particular, we focus on the boundary value problem, in which we take realistic shapes for the outer magnetic flux surface (close to the magnetopause) and plasma pressure distributions as model inputs and obtain the total pressure variation in the tail as a by‐product of the model.
Method for in‐flight satellite calibration in the ultraviolet using radiative transfer calculations, with application to Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY)
Authors: Tilstra L. G. , van Soest G. , Stammes P.
Published: September 2005

We present a reflectance validation method, using a polarized radiative transfer model as a reference. The method involves calculating the complete radiative transfer in the ultraviolet for a carefully selected, natural, cloud‐free Earth target. An extensive sensitivity study shows that in the ultraviolet, the ozone profile (mainly below 330 nm) and the surface albedo (mainly above 330 nm) are the important parameters that affect the reflectance and are therefore the major sources of error in the modeled reflectances. The accuracy with which the reflectance in the UV range of 240–400 nm can be calculated, because of uncertainty in input parameters, is 2–6%, depending on wavelength. The method is applied to Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY), using a cloud‐free scene over the Sahara desert. The reflectance measured by SCIAMACHY turns out to show a scan‐angle‐independent calibration error of 10–25% for this particular Sahara target. The result is confirmed for ocean and vegetation targets.
Helicase89B is a Mot1p/BTAF1 homologue that mediates an antimicrobial response in Drosophila
Authors: Yagi Yoshimasa , Ip Y Tony
Published: September 2005

We have identified a novel component, Helicase89B, that is required for the inducible antimicrobial response in Drosophila larvae by means of a P‐element insertional genetic screen. Helicase89B belongs to the Mot1p/BTAF1 subfamily of SNF2‐like ATPases. This subfamily can interact with TATA‐binding proteins, but whether the interaction leads to gene activation or repression is being debated. We found that Helicase89B is required for the inducible expression of antimicrobial peptide genes but not for the inducible expression of heat‐shock genes. The antimicrobial peptide genes are activated by the Toll and immune deficiency (IMD) signalling pathways. Genetic experiments show that Helicase89B acts downstream of DIF and Relish, the two nuclear factor‐κB (NF‐κB)‐related transcription factors that mediate Toll‐ and IMD‐stimulated antimicrobial response. Thus, Helicase89B positively regulates gene expression during innate immune response and may act as a link between NF‐κB‐related transcription factors and the basal transcription machinery.
Effects of the Chemokine CCL2 on Blood–Brain Barrier Permeability during Ischemia–Reperfusion Injury
Authors: Dimitrijevic Oliver B , Stamatovic Svetlana M , Keep Richard F , Andjelkovic Anuska V
Published: September 2005

The chemokine CCL2 is considered as one of the main effectors driving postischemic infiltration of monocytes into the brain parenchyma. New experimental data, however, suggest that CCL2 could also participate in blood–brain barrier (BBB) ‘opening’ during the transmigration of monocytes. The current study examines the role of CCL2 in regulating BBB permeability after ischemia in vitro. To address this issue, an in vitro BBB model (coculture of astrocytes and brain endothelial cells) was subjected to 5 h of oxygen glucose deprivation, followed by reoxgenation ( in vitro ischemia/reperfusion (I/R)) for 0 to 48 h. During reperfusion, there was a biphasic enhancement of barrier permeability, with a 200-fold increase in barrier permeability to FITC-albumin at 6 h and a further period of disruption around 24 h. The latter coincided with increased secretion of CCL2 by both astrocytes and brain endothelial cells and increased levels of the CCL2 receptor, CCR2. Applying antisense oligonucleotide or neutralizing antibody to block CCL2 significantly decreased I/R-induced enhancement of BBB permeability (approximately twofold) and redistribution of tight-junction (TJ) proteins (occludin, zonula occluden-1, 2, claudin-5). Similarly, absence of CCR2 from endothelial cells caused stabilization of TJ complexes and decreased the permeability of brain endothelial barrier during in vitro I/R. These data suggest CCL2/CCR2 has an important role in regulating brain endothelial permeability and might be a potential novel therapeutic target for stroke.
Measurement of Cerebral Oxidative Metabolism with Near-Infrared Spectroscopy: A Validation Study
Authors: Tichauer Kenneth M , Hadway Jennifer A , Lee Ting-Yim , Lawrence Keith S
Published: September 2005

Predicting the onset of secondary energy failure after a hypoxic–ischemic insult in newborns is critical for providing effective treatment. Measuring reductions in the cerebral metabolic rate of oxygen (CMRO2) may be one method for early detection, as hypoxia–ischemia is believed to impair oxidative metabolism. We have developed a near-infrared spectroscopy (NIRS) technique based on the Fick Principle for measuring CMRO2. This technique combines cerebral blood flow (CBF) measurements obtained using the tracer indocyanine green with measurements of the cerebral deoxy-hemoglobin (Hb) concentration. In this study, NIRS measurements of CMRO2 were compared with CMRO2 determined from the product of CBF and the cerebral arteriovenous difference in oxygen measured from blood samples. The blood samples were collected from a peripheral artery and the sagittal sinus. Eight piglets were subjected to five cerebral metabolic states created by varying the plane of anesthesia. No significant difference was found between CMRO2 measurements obtained with the two techniques at any anesthetic level ( P > 0.5). Furthermore, there was a strong correlation when concomitant CMRO2 values from the two techniques were compared ( R2 = 0.88, P< 0.001). This work showed that CMRO2 can be determined accurately by combining NIRS measurements of CBF and Hb. Since NIRS is safe and measurements can be obtained at the bedside, it is believed that this technique could assist in the early diagnosis of cerebral energy dysfunction after hypoxia–ischemia.
The usefulness of higher-order constitutive relations for describing the Knudsen layer
Authors: Lockerby Duncan A. , Reese Jason M. , Gallis Michael A.
Published: September 2005

The Knudsen layer is an important rarefaction phenomenon in gas flows in and around microdevices. Its accurate and efficient modeling is of critical importance in the design of such systems and in predicting their performance. In this paper we investigate the potential that higher-order continuum equations may have to model the Knudsen layer, and compare their predictions to high-accuracy DSMC (direct simulation Monte Carlo) data, as well as a standard result from kinetic theory. We find that, for a benchmark case, the most common higher-order continuum equation sets (Grad’s 13 moment, Burnett, and super-Burnett equations) cannot capture the Knudsen layer. Variants of these equation families have, however, been proposed and some of them can qualitatively describe the Knudsen layer structure. To make quantitative comparisons, we obtain additional boundary conditions (needed for unique solutions to the higher-order equations) from kinetic theory. However, we find the quantitative agreement with kinetic theory and DSMC data is only slight.
The impact of subcontinuum gas conduction on topography measurement sensitivity using heated atomic force microscope cantilevers
Authors: Masters Nathan D. , Ye Wenjing , King William P.
Published: September 2005

Nanometer-scale topographical imaging using heated atomic force microscope (AFM) cantilevers, referred to here as thermal sensing AFM (TSAFM), is a promising technology for high resolution topographical imaging of nanostructured surfaces. Heated AFM cantilevers were developed for high-density data storage, where the heated cantilever tip can form and detect 20 nm indents made in a thermoplastic polymer. The scan height of the cantilever heater platform is typically near 500 nm, but could be made much smaller to improve reading sensitivity. Under atmospheric conditions the continuum models used in previous studies to model the gas phase heat transfer are invalid for the smallest operating heights. The present study uses a molecular model of subcontinuum heat transfer coupled with a finite difference simulation to predict the behavior of a TSAFM system. A direct simulation Monte Carlo model and a kinetic theory based macromodel are separately developed and used to model subcontinuum gas conduction. For the working gas (argon) the simple macromodel is found to be accurate and is used to predict cantilever operation. This systems-level modeling approach for TSAFM operation can aid data interpretation and seeks to improve microcantilever design.
An extended volume-of-fluid method for micro flows with short-range interactions between fluid interfaces
Authors: Hardt S.
Published: September 2005

A formulation is developed allowing to take into account the interaction of fluid interfaces in computational methods for free-surface flow. The necessity for such an extension of the standard computational approaches is traced back to a large number of experimental and theoretical results showing that in the presence of surfactants, fluid interfaces often interact in such a way that coalescence of bubbles or droplets is slowed down or suppressed. The strategy pursued in this paper to incorporate such effects relies on a Debye-screened scalar field which develops steep gradients in the vicinity of an interface. The force density acting in a gap between two interfaces is computed using a function of the local field values and a cut off to eliminate those regions where no interaction takes place. It is shown that in such a way a power-law behavior of the force as a function of separation between the interfaces can be reproduced. The model is implemented into a standard volume-of-fluid scheme and it is exemplified that, compared to conventional approaches, completely different scenarios for micro flows of droplets can be reproduced. The important qualitative difference is that coalescence is avoided, so that the formation and transport of multibubble∕multidroplet arrangements can be studied.
Pinning effects and their breakdown for a Ginzburg–Landau model with normal inclusions
Authors: Alama Stan , Bronsard Lia
Published: September 2005

We study a Ginzburg–Landau model for an inhomogeneous superconductor in the singular limit as the Ginzburg–Landau parameter κ=1∕ϵ→∞. The inhomogeneity is represented by a potential term V(ψ)=14(a(x)−∣ψ∣2)2, with a given smooth function a(x) which is assumed to become negative in finitely many smooth subdomains, the “normally included” regions. For bounded applied fields (independent of the Ginzburg–Landau parameter κ=1∕ϵ→∞) we show that the normal regions act as “giant vortices,” acquiring large vorticity for large (fixed) applied field hex. For hex=O(∣lnϵ∣) we show that this pinning effect eventually breaks down, and free vortices begin to appear in the superconducting region where a(x)>0, at a point set which is determined by solving an elliptic boundary-value problem. The associated operators are strictly but not uniformly elliptic, leading to some regularity questions to be resolved near the boundaries of the normal regions.
Global bifurcation structure of a one-dimensional Ginzburg–Landau model
Authors: Kosugi Satoshi , Morita Yoshihisa , Yotsutani Shoji
Published: September 2005

We consider an equation of a simplified Ginzburg–Landau model of superconductivity in a one-dimensional ring. The equation for a complex order parameter ψ has two real parameters μ and λ related to the magnitude of an applied magnetic field and the Ginzburg–Landau parameter, respectively. The purpose of this paper is to reveal a global bifurcation structure for the equation in the parameter space (μ,λ). In particular we show that there exist modulating amplitude solutions which bifurcate from constant amplitude solutions, and how the bifurcation branches of such solutions continue or disappear as μ varies. We also determine the minimizer of the energy functional.
Classical solutions to the time-dependent Ginzburg–Landau equations for a bounded superconducting body in a vacuum
Authors: Bauman Patricia , Jadallah Hala , Phillips Daniel
Published: September 2005

The initial value problem for the time dependent Ginzburg–Landau equations used to model the electrodynamics of a superconducting body surrounded by a vacuum in R3 is studied. We prove existence, uniqueness, and regularity results for solutions in the Coulomb, Lorentz, and temporal gauges.
Numerical approximations of the Ginzburg–Landau models for superconductivity
Authors: Du Qiang
Published: September 2005

In this paper, we review various methods for the numerical approximations of the Ginzburg–Landau models of superconductivity. Particular attention is given to the different treatment of gauge invariance in both the finite element, finite difference, and finite volume settings. Representative theoretical results, typical numerical simulations, and computational challenges are presented. Generalizations to other relevant models are also discussed.
Ginzburg–Landau model of a liquid crystal with random inclusions
Authors: Berlyand L. , Khruslov E.
Published: September 2005

We consider a Ginzburg–Landau three-dimensional functional with a surface energy term to model a nematic liquid crystal with inclusions. The locations and radii of the inclusions are randomly distributed and described by a set of finite dimensional distribution functions. We show that the presence of inclusions can be accounted for by an effective potential. Our main objectives are (a) to derive the sufficient conditions on the distribution functions such that the solutions converge in probability to a solution of a homogenized deterministic problem and (b) to compute the effective potential.
Topologically driven local minimizers of the Oseen-Frank energy
Authors: Kim Yun-hui , Rubinstein Jacob , Sternberg Peter
Published: September 2005

The analogy between certain liquid crystals and superconductivity has been recognized and explored by a number of scientists. In particular, mathematical techniques first developed within the Ginzburg–Landau theory of superconductivity have proven useful when adapted to the setting of liquid crystals. Here we pursue nontrivial stable liquid crystal configurations, motivated by an approach used by the authors in the setting of Ginzburg–Landau to produce persistent currents in topologically nontrivial domains. Our starting point is the Oseen-Frank energy for a nematic, but we add to the standard model a term that penalizes deviation of the director from a given plane.
Potential energy surface and second virial coefficient of methane-water fromab initiocalculations
Authors: Akin-Ojo Omololu , Szalewicz Krzysztof
Published: September 2005

Six-dimensional intermolecular potential energy surfaces (PESs) for the interaction of CH4 with H2O are presented, obtained from ab initio calculations using symmetry-adapted perturbation theory (SAPT) at two different levels of intramonomer correlation and the supermolecular approach at three different levels of electron correlation. Both CH4 and H2O are assumed to be rigid molecules with interatomic distances and angles fixed at the average values in the ground-state vibration. A physically motivated analytical expression for each PES has been developed as a sum of site-site functions. The PES of the CH4–H2O dimer has only two symmetry-distinct minima. From the SAPT calculations, the global minimum has an energy of −1.03kcal∕mol at a geometry where H2O is the proton donor, HO–H⋯CH4, with the O–H–C angle of 165°, while the secondary minimum, with an energy of −0.72kcal∕mol, has CH4 in the role of the proton donor (H3C–H⋯OH2). We estimated the complete basis set limit of the SAPT interaction energy at the global minimum to be −1.06kcal∕mol. The classical cross second virial coefficient B12(T) has been calculated for the temperature range 298–653K. Our best results agree well with some experiments, allowing an evaluation of the quality of experimental results.
Calculation of heat capacities of light and heavy water by path-integral molecular dynamics
Authors: Shiga Motoyuki , Shinoda Wataru
Published: September 2005

As an application of atomistic simulation methods to heat capacities, path-integral molecular dynamics has been used to calculate the constant-volume heat capacities of light and heavy water in the gas, liquid, and solid phases. While the classical simulation based on conventional molecular dynamics has estimated the heat capacities too high, the quantum simulation based on path-integral molecular dynamics has given reasonable results based on the simple point-charge/flexible potential model. The calculated heat capacities (divided by the Boltzmann constant) in the quantum simulation are 3.1 in the vapor H2O at 300 K, 6.9 in the liquid H2O at 300 K, and 4.1 in the ice IhH2O at 250 K, respectively, which are comparable to the experimental data of 3.04, 8.9, and 4.1, respectively. The quantum simulation also reproduces the isotope effect. The heat capacity in the liquid D2O has been calculated to be 10% higher than that of H2O, while it is 13% higher in the experiment. The results demonstrate that the path-integral simulation is a promising approach to quantitatively evaluate the heat capacities for molecular systems, taking account of quantum-mechanical vibrations as well as strongly anharmonic motions.
NMR relaxation and pulsed-gradient diffusion study of polyethylene nanocomposites
Authors: Ozisik R. , Zheng J. , Dionne P. J. , Picu C. R. , von Meerwall E. D.
Published: September 2005

We performed pulsed-gradient spin-echo nuclear-magnetic-resonance (NMR) experiments on zinc oxide filled polyethylene. The molecular weights of the polyethylene samples ranged between 808 and 33000g∕mol, and four different zinc oxide samples were used: 27-, 33-, 51-, and 2500-nm-diameter particles. The results of these experiments showed that the diffusion coefficients of the polyethylene chains did not change with nanofiller content, but a drastic change is observed in the NMR relaxation spectrum in spin-spin-relaxation experiments. At fixed zinc oxide content and polyethylene molecular weight (close to entanglement), the system with the smallest zinc oxide showed the most rigid environment. At high polyethylene molecular weights, this effect was still observable but the difference between the three investigated systems was very small, suggesting that the system was dominated by entanglements.