bluuebunny/crossref_metadata_2025 huggingface dataset:
AL-AHBASH AND WAHHABIYYA: INTERPRETATIONS OF ISLAM
Authors: Kabha Mustafa , Erlich Haggai
Published: October 2006

Islam is a universal religion and culture. Scholars who tend to focus on Islam in specific societies may overlook connections that, over the centuries, were important in shaping various Islamic intercultural dialogs. One case in point is the role of Ethiopia in the history of Islam. Although situated next door to the cradle of Islam, Ethiopia conveniently has been perceived by many Western historians of the Arab Middle East as an African “Christian island,” and as largely irrelevant. In practice, however, the Christian-dominated empire has remained meaningful to all Muslims from Islam's inception. It has also been the home of Islamic communities that maintained constant contact with the Middle East. Indeed, one of the side aspects of the resurgence of political Islam since the 1970s is the emergence in Lebanon of the “The Association of Islamic Philanthropic Projects” (Jamעiyyat al-Mashariע al-Khayriyya al-Islamiyya), better known as “The Ethiopians,” al-Ahbash. Its leader came to Beirut from Ethiopia with a rather flexible interpretation of Islam, which revolved around political coexistence with Christians. Al-Ahbash of Lebanon expanded to become arguably the leading factor in the local Sunni community. They opened branches on all continents and spread their interpretation of Islam to many Islamic as well as non-Islamic countries. This article is an attempt to relate some of the Middle Eastern–Ethiopian Islamic history as the background to an analysis of a significant issue on today's all-Islamic agenda. It aims to present the Ahbash history, beliefs, and rivalry with the Wahhabiyya beginning in the mid-1980s. It does so by addressing conceptual, political, and theological aspects, which had been developed against the background of Ethiopia as a land of Islamic–Christian dialogue, and their collision with respective aspects developed in the Wahhabi kingdom of the Saudis. The contemporary inner-Islamic, Ahbash-Wahhabiyya conceptual rivalry turned in the 1990s into a verbal war conducted in traditional ways, as well as by means of modern channels of Internet exchanges and polemics. Their debate goes to the heart of Islam's major dilemmas as it attracts attention and draws active participation from all over the world.
Multiple dehiscence of semicircular canals
Authors: Rajenderkumar D , Farrell K L , Alles R M , Savy L
Published: October 2006

Dehiscence of the semicircular canal is an uncommon condition and has been reported to involve the roof of the superior semicircular canal. We describe a case with dehiscence of four semicircular canals and in areas not involving the roof of the superior semicircular canal. Features that assist the diagnosis of this condition are reviewed, along with the current literature.
Professional occupation after cochlear implantation
Authors: Kos M-I , Degive C , Boex C , Guyot J-P
Published: October 2006

The aims of this study were to verify whether cochlear implants helped profoundly deaf adults to maintain or even to develop their professional occupations, and to identify other elements that may contribute to or, on the contrary, impede such patients' professional success. All adult patients received a questionnaire concerning their professional activities before and after implantation. Demographic data, health information, hearing performance and degree of satisfaction with the implant were also considered. Sixty-seven adults had been implanted, with three different devices, since 1985. At the time of implantation, 34 had been professionally active. After implantation, 29 had remained professionally active, four of whom reported positive developments in their careers. Five patients had become professionally inactive. Those patients who had previously been professionally inactive remained so. There had been no difference in performance, either between different types of cochlear implants or between professionally active or inactive patients. The implanted patients had kept their jobs and many of them had developed their professional skills. In spite of this, cochlear implants may still be perceived as proving insufficiently satisfactory hearing to enable professionally inactive patients to reintegrate and to facilitate further learning or career developments.
Predictive factors for recurrent non-toxic goitre in an endemic region
Authors: Erbil Y , Bozbora A , Tulumoğlu Yanık B , Özbey N , Salmaslıoğlu A , Özarmağan S
Published: October 2006

Aims: We aimed to determine the risk factors for recurrence and to assess the complication rate associated with surgery for benign, recurrent goitre.

Methods: We studied 125 consecutive patients with recurrent goitre who underwent re-operative thyroid surgery (group one). Patients in the control group were randomly selected from those undergoing their first procedure during the same period (group two). Age, initial surgery, presence of multinodular goitre, presence of carcinoma in the resected thyroid tissue, interval between initial operation and re-operation, and complications were analysed and compared for the two groups.

Results: The mean age (± standard deviation) was found to be significantly greater in group one compared with group two. The mean age at the time of primary thyroid operation was found to be significantly less in group one compared with group two. The interval between the initial and the re-operative procedures was a mean of 15.8±eight years. Initial surgery was conservative. Papillary thyroid carcinoma was found in 14/125 (11 per cent) of group one patients. The incidence of complications was found to be significantly higher in group one compared with group two.

Conclusion: The incidence of recurrent goitre has been directly related to conservative thyroid surgery and to the retention of large amounts of remnant tissue. To avoid recurrent goitre and possible re-operative complications, total or near-total thyroidectomy should be performed in all patients with bilateral, multinodular goitre, especially in endemic regions.
The polar ship Frithjof
Authors: Kjær Kjell-G.
Published: October 2006

Frithjof participated in several North Pole expeditions between 1898 and 1907 and was also involved in several relief expeditions. Her most frequent commander was Captain Johan Kjeldsen, who was an internationally famous ice pilot. Frithjof was built in 1884 at Stokke on Oslo fjord, Norway. After being employed in the sealing trade for some years, Frithjof was sold to an Icelandic concern. In 1891 she returned to Norwegian ownership and, in 1898, was chartered for Walter Wellman's North Pole expedition of the years 1898–1899. In 1900, she was the expedition ship for the Kolthoff expedition to Greenland, Spitsbergen and Jan Mayen. Between 1901 and 1904 she was engaged in Ziegler's North Pole expeditions both as expedition ship and as relief vessel. In 1903 the Swedish government chartered Frithjof in order to search for the Nordenskjöld expedition in the Antarctic. In 1906–7 the ship was again chartered for Wellman's North Pole airship expeditions. In late September 1907, Frithjof sailed from Tromsø on a relief expedition to search for Laura, an expedition vessel to Greenland that had not been heard of for three months. On 5 October 1907 she was lost in a storm off Iceland and only one man survived from her crew of 17.
The memorials on Beechey Island, Nunavut, Canada: an historical and pictorial survey
Authors: Powell Brian D.
Published: October 2006

This paper describes observations made on visits to Beechey Island in 1999, 2002, and 2005. These visits were made in order to examine the memorials on this very important site for Arctic exploration and to make an extensive photographic record of them. Their history and present condition are described. There are some inconsistencies and confusion in the scattered literature concerning their history and this paper seeks to resolve these matters. It is hoped that further investigations to resolve the few remaining problems, will be conducted and that a systematic nomenclature, which is suggested in the paper, will be adopted for the memorials. Restoration, repair, and regular maintenance of the memorials are becoming necessary and appropriate funding for this is required before it is too late. Close regulation of the erection of more modern memorials and burials, some of which, in the author's view, detract from the significance, solemnity, and appearance of the island is desirable. With the growing number of airborne and ship borne travellers and tourists visiting Beechey Island, a degree of supervision may become necessary in order to ensure that the memorials remain intact. Beechey Island is one of the most important heritage locations in Canada and in the history of Arctic exploration by the Royal Navy in the nineteenth century.
Nineteenth century sealing sites on Rugged Island, South Shetland Islands
Authors: Pearson Michael , Stehberg Ruben
Published: October 2006

The South Shetland Islands were discovered in 1819. Almost immediately the fur seal population was intensively exploited and this lasted through the early years of the 1820s, by which time seal numbers had been so depleted that sealing became uneconomic. Sealing was revived for both fur seals and Elephant seals at several periods later in the century. Sealers were put ashore in gangs and built makeshift shelters in which to live. Many of these have been identified on the South Shetlands, and a number have been excavated, though few with archaeological method. Fifty known sites are identified. The paper outlines the survey and excavation of two sites on Rugged Island by archaeologists from Australia and from the Chilean National Natural History Museum. One site relates to the sealing era of the 1820s, while the second may be associated with a marooned sealing gang in the 1870s. The nature of the occupation sites on the South Shetlands is analysed in relation to the social and operational context of the merchant navies of Britain and the USA in the nineteenth century. This is seen as a more directly relevant context for assessing physical evidence than is the application of theories of global capitalist systems.
Public Opinion on the Role of Religion in Political Leadership: A Multi-level Analysis of Sixty-three Countries
Authors: CARLSON MATTHEW , LISTHAUG OLA
Published: October 2006

Are there significant variations across major religious faiths about the proper political roles of religion? Using recent World Values/European Values data from 63 countries we study the attitudes of mass publics on two separate aspects of this question. First, should religious beliefs be used as a criterion for selecting political leaders (dimension I)? Second, should religious leaders use their position for political influence (dimension II)? For dimension I we find that Muslims are somewhat more likely than followers of other faiths and denominations to say that religious beliefs are important in selecting leaders. The remaining results of our investigation somewhat weaken or modify this result. On dimension II we find that Muslims do not stand out as comparatively favorable towards the view that religious leaders shall use their position for political influence. Finally, we find a negative, albeit weak and somewhat irregular effect of education on attitudes towards a close link between religion and political leadership (dimension I). However, this effect holds up equally well for Muslims as for other denominations, suggesting that Muslims are not immune to the effects of secularization.
The Effect of Dual Candidacy on Voting Decisions
Authors: HIZEN YOICHI
Published: October 2006

This article conducts a decision theoretic analysis of the effect of dual candidacy on voting decisions in the Japanese variant of the mixed electoral system, where each candidate can run in both a single-member district (SMD) and a proportional representation (PR) block, and dual candidates can be ranked either individually or equally in parties' PR lists: their post-election ranking is determined by their SMD votes. The model shows that dual candidacy differentiates the mixed system from merely the simultaneous use of the SMD and PR systems. That is, if an SMD candidate also runs in the PR block, it lowers voters' utility increment obtained by casting their SMD votes for him. If he is ranked equally in the PR list, however, SMD votes for him may help him win a PR seat against other equally ranked dual candidates, which enables dual candidacy accompanied by equal ranking to attract more SMD votes.
Attitudes toward disease and prognosis disclosure and decision making for terminally ill patients in Japan, based on a nationwide random sampling survey of the general population and medical practitioners
Authors: MIYASHITA,. MITSUNORI , HASHIMOTO SHUJI , KAWA MASAKO , SHIMA YASUO , KAWAGOE HIROMI , HASE TSUNETO , SHINJO YAE , SUEMASU KEIICHI
Published: October 2006

Objective:Employing a nationwide cross-sectional survey, we investigated the Japanese general population's attitudes toward disease and prognosis disclosure and related factors. Furthermore, we investigated Japanese medical practitioners' attitudes toward disease and prognosis disclosure for patients and decision making.

Methods:A nationwide anonymous questionnaire survey was conducted. A total of 5000 individuals were randomly sampled from the general population and 3104 physicians and 6059 nurses were randomly sampled in Japan.

Results:Finally, 2422 people from the general population (response rate, 48%), 1577 physicians (51%), and 3361 nurses (56%) returned questionnaires. Among the general population, 73% of participants answered that they “want to know” about their disease and prognosis when in an incurable disease state. Ninety percent desired direct disclosure and 8% disclosure through their family. However, few medical practitioners answered “patient himself” (physician 3%, nurses 4%) as the person whom they would primarily notify about the disease and prognosis when in charge of a patient with an incurable disease. On the other hand, physicians answered “family” most frequently (59%), whereas nurses most commonly responded, “depends on patient's condition” (63%).

Significance of research:Several detailed analyses of factors associated with prognosis disclosure were conducted. Japanese physicians need to carefully communicate with the patients individually about whether direct disclosure or disclosure primarily to the family is preferred.
Current Task Activation Predicts General Effects of Advance Preparation in Task Switching
Authors: Poljac Edita , Haan Ab de , Galen Gerard P. van
Published: October 2006

Two experiments investigated the way that beforehand preparation influences general task execution in reaction-time matching tasks. Response times (RTs) and error rates were measured for switching and nonswitching conditions in a color- and shape-matching task. The task blocks could repeat (task repetition) or alternate (task switch), and the preparation interval (PI) was manipulated within-subjects (Experiment 1) and between-subjects (Experiment 2). The study illustrated a comparable general task performance after a long PI for both experiments, within and between PI manipulations. After a short PI, however, the general task performance increased significantly for the between-subjects manipulation of the PI. Furthermore, both experiments demonstrated an analogous preparation effect for both task switching and task repetitions. Next, a consistent switch cost throughout the whole run of trials and a within-run slowing effect were observed in both experiments. Altogether, the present study implies that the effects of the advance preparation go beyond the first trials and confirms different points of the activation approach ( Altmann, 2002) to task switching.
New evidence for the reawakening of Teide volcano
Authors: Gottsmann J. , Wooller L. , Martí J. , Fernández J. , Camacho A. G. , Gonzalez P. J. , Garcia A. , Rymer H.
Published: October 2006

Geophysical signals accompanying the reactivation of a volcano after a period of quiescence must be evaluated as potential precursors to impending eruption. Here we report on the reactivation of the central volcanic complex of Tenerife, Spain, in spring 2004 and present gravity change maps constructed by time‐lapse microgravity measurements taken between May 2004 and July 2005. The gravity changes indicate that the recent reactivation after almost a century of inactivity was accompanied by a sub‐surface mass addition, yet we did not detect widespread surface deformation. We find that the causative source was evolving in space and time and infer fluid migration at depth as the most likely cause for mass increase. Our results demonstrate that, even in the absence of previous baseline data and ground deformation, microgravity measurements early in developing crises provide crucial insight into the dynamic changes beneath a volcano.
Radial velocity observations of the extended lunar sodium tail
Authors: Mierkiewicz E. J. , Line M. , Roesler F. L. , Oliversen R. J.
Published: October 2006

We report the first velocity resolved sodium 5889.950 Å line profile observations of the lunar sodium tail observed in the anti‐lunar direction near new Moon. These observations were made on 29 March 2006, 27 April 2006 and 28 April 2006 from Pine Bluff (WI) observatory with a double etalon Fabry‐Perot spectrometer at a resolving power of ∼80,000. The observations were made within 2–14 hours from new Moon, pointing near the anti‐lunar point. The average observed radial velocity of the lunar sodium tail in the vicinity of the anti‐lunar point for the three nights reported was 12.4 km s−1 (from geocentric zero). The average Doppler width of a single Gaussian fit to the emission line was 7.6 km s−1. In some cases the line profile appears asymmetric, with excess lunar sodium emission at higher velocity (∼18 km s−1 from geocentric zero) that is not accounted for by our single Gaussian fit to the emission.
A Monte Carlo error analysis for basal sliding velocity calculations
Authors: Chandler D. M. , Hubbard A. L. , Hubbard B. P. , Nienow P. W.
Published: October 2006

Since glacier beds are mostly inaccessible, numerical inversion of the surface velocity field provides a valuable method for calculating the basal shear stress and sliding velocity. However, previous theoretical studies (limited either to planar slabs or linear ice rheology) have suggested small errors in surface velocity measurements lead to large uncertainties in calculated basal sliding. Here a numerical ice flow model and Monte Carlo simulation are used to calculate the sliding velocity and basal shear stress and their associated uncertainties from field measurements of surface velocity along a two‐dimensional long section of Glacier de Tsanfleuron, Switzerland. The model does not require the restrictive assumption of a sliding law since both sliding and basal shear stress are calculated independently and can include a spatially variable rate factor in the flow law for ice. Results indicate that sliding contributes between 45 and 84% of the surface velocity and that calculated sliding velocities are strongly dependent on ice rheology. Amplification of surface velocity errors is generally smaller than theoretical estimates and is a power law function of the horizontal grid spacing in the ice flow model.
Cellular functions of the BRCA tumour-suppressor proteins
Authors: Boulton S.J.
Published: October 2006

Inherited germline mutations in either BRCA1 or BRCA2 confer a significant lifetime risk of developing breast or ovarian cancer. Defining how these two genes function at the cellular level is essential for understanding their role in tumour suppression. Although BRCA1 and BRCA2 were independently cloned over 10 years ago, it is only in the last few years that significant progress has been made towards understanding their function in cells. It is now widely accepted that both genes play critical roles in the maintenance of genome stability. Evidence implicates BRCA2 as an integral component of the homologous recombination machinery, whereas BRCA1 is an E3 ubiquitin ligase that has an impact on DNA repair, transcriptional regulation, cell-cycle progression and meiotic sex chromosome inactivation. In this article, I will review the most recent advances and provide a perspective of potential future directions in this field.
Mechanisms controlling the expression of the components of the exocytotic apparatus under physiological and pathological conditions
Authors: Abderrahmani A. , Plaisance V. , Lovis P. , Regazzi R.
Published: October 2006

The last decade has witnessed spectacular progress in the identification of the protein apparatus required for exocytosis of neurotransmitters, peptide hormones and other bioactive products. In striking contrast, our knowledge of the mechanisms determining the expression of the components of the secretory machinery has remained rudimentary. Since modifications in secretory functions are associated with several physiological processes and contribute to the development of human pathologies, a better knowledge of the control of the expression of the genes involved in exocytosis is urgently needed. Recent studies have led to the identification of transcription factors and other regulatory molecules such as microRNAs that modulate the cellular level of key controllers of the exocytotic process. These findings furnish a new perspective for understanding how secretory functions can adapt to normal physiological conditions and shed light on the mechanisms involved in the development of important human diseases such as diabetes mellitus characterized by defective release of bioactive compounds.
Structural basis for the nuclear protein import cycle
Authors: Stewart M.
Published: October 2006

Transport of macromolecules between the nuclear and cytoplasmic compartments through NPCs (nuclear pore complexes) is mediated by soluble transport factors that are commonly members of the importin-β superfamily. In the nuclear protein import cycle, importin-β binds cargo in the cytoplasm (usually via the importin-α adaptor) and transports it through NPCs with which it interacts transiently by way of NPC proteins (‘nucleoporins’) that contain distinctive FG (Phe-Gly) sequence repeats. In the nucleus, Ran-GTP binds to importin-β, dissociating the import complex. The importin-β–Ran-GTP complex recycles to the cytoplasm, whereas importin-α is recycled by the importin-β family member CAS (cellular apoptosis susceptibility protein) complexed with Ran-GTP. Cytoplasmic RanGAP (Ran GTPase-activating protein) dissociates these complexes, freeing the importins for another import cycle. Crystallography and biochemical and cellular studies have enabled a molecular description of the transport cycle to be developed and tested using protein engineering and computer modelling. Importin-β family members are elongated flexible molecules that adapt their shape to encircle their cargoes. Ran-GTP binds at three sites along importin-β and CAS, locking the molecules into a rigid conformation that is unable to bind cargoes effectively. Interactions between transport factors and key nucleoporins (such as Nup1p, Nup2p and Nup50) accelerate the formation and dissolution of many of these complexes.
FOXO transcription factors: key regulators of cell fate
Authors: Lam E.W.-F. , Francis R.E. , Petkovic M.
Published: October 2006

FOXO (forkhead box O) transcription factors are crucial regulators of cell fate. This function of FOXO proteins relies on their ability to control diverse and at times, opposing cellular functions, such as proliferation, differentiation, DNA repair, defence against oxidative stress damage and apoptosis, in response to hormones, growth factors and other environmental cues. This review discusses our current understanding of the regulation and role of FOXO transcription factors in determining cell fate and highlights their relevance to tumorigenesis and drug resistance.
Reversible ubiquitination regulates the Smad/TGF-β signalling pathway
Authors: Wicks S.J. , Grocott T. , Haros K. , Maillard M. , Dijke P. ten , Chantry A.
Published: October 2006

TGF-β (transforming growth factor-β) signals through serine/threonine kinase receptors and intracellular Smad transcription factors. An important regulatory step involves specific ubiquitination by Smurfs (Smad–ubiquitin regulatory factors), members of the HECT (homologous to E6-associated protein C-terminus) ubiquitin ligase family, which mediate the proteasomal degradation of Smads and/or receptors. Recently, we have defined a novel interaction between Smads and UCH37 (ubiquitin C-terminal hydrolase 37), a DUB (de-ubiquitinating enzyme) that could potentially counteract Smurf-mediated ubiquitination. We have demonstrated specific interactions between UCH37 and inhibitory Smad7, as well as weaker associations with Smad2 and Smad3. Importantly, Smad7 can act as an adaptor able to recruit UCH37 to the type I TGF-β receptor. Consequently, UCH37 dramatically up-regulates TGF-β-dependent gene expression by de-ubiquitinating and stabilizing the type I TGF-β receptor. Our findings suggest that competing effects of ubiquitin ligases and DUBs in complex with Smad7 can serve to fine-tune responses to TGF-βs under various physiological and pathological conditions. Studies are currently under way using activity-based HA (haemagglutinin)-tagged ubiquitin probes to identify the full spectrum of DUBs that impact on Smad/TGF-β signalling activity.
The G-protein-coupled receptor 40 family (GPR40–GPR43) and its role in nutrient sensing
Authors: Covington D.K. , Briscoe C.A. , Brown A.J. , Jayawickreme C.K.
Published: October 2006

Recent deorphanization efforts have paired the G-protein-coupled receptors GPR40, GPR41 and GPR43 with fatty acids as endogenous ligands. While carboxylic acids have been historically known to serve as fuel sources and biomarkers of disease, these studies demonstrate that fatty acids can act as signalling molecules at the cell-surface level. This receptor subfamily shares approx. 30% identity among members, with some limited cross-over between ligand activities. Generalized expression patterns within the pancreatic β-cell, adipose depots and the gastrointestinal tract infer involvement in energy source recognition, absorption, storage and/or metabolism. GPR40, activated by medium and long-chain fatty acids, has been shown to potentiate insulin secretion at the β-cell, and has been hypothesized to participate in the detrimental effects of chronic fatty acid exposure on β-cell function. GPR41 and GPR43 have been reported to stimulate leptin release and adipogenesis respectively via activation by short-chain fatty acids. These common themes implicate GPR40, GPR41 and GPR43 in playing significant roles in metabolic diseases, such as diabetes, obesity and the metabolic syndrome.
Hsp90 chaperone control over transcriptional regulation by the yeast Slt2(Mpk1)p and human ERK5 mitogen-activated protein kinases (MAPKs)
Authors: Piper P.W. , Truman A.W. , Millson S.H. , Nuttall J.
Published: October 2006

Cell integrity MAPK (mitogen-activated protein kinase) function can be provided in yeast cells by either the native Slt2(Mpk1)p of yeast or by a heterologously expressed human ERK5 (extracellular-signal-regulated kinase 5). Both of these MAPKs need the Hsp90 (heat-shock protein 90) chaperone for their activation, so that when Hsp90 function is compromised their activities are low. This, in turn, affects the capacity of these MAPKs to control the transcription factors that regulate cell integrity genes.
Phosphorylation of Zn(II)2Cys6 proteins: a cause or effect of transcriptional activation?
Authors: Leverentz M.K. , Reece R.J.
Published: October 2006

Many Zn(II)2Cys6 transcriptional regulators exhibit changes in phosphorylation that are coincident with their roles in transcriptional activation. It is, however, unclear whether these changes occur as a cause of, or as a result of, transcriptional activation. In this paper, we explore the relationship between these two events and collate data available on the phosphorylation state of those transcriptional regulators where the relationship has not been clearly identified.
The role of scaffold proteins in MEK/ERK signalling
Authors: Sacks D.B.
Published: October 2006

Signal transduction networks allow cells to recognize and respond to changes in the extracellular environment. All eukaryotic cells have MAPK (mitogen-activated protein kinase) pathways that participate in diverse cellular functions, including differentiation, survival, transformation and movement. Five distinct groups of MAPKs have been characterized in mammals, the most extensively studied of which is the Ras/Raf/MEK [MAPK/ERK (extracellular-signal-regulated kinase) kinase]/ERK cascade. Numerous stimuli, including growth factors and phorbol esters, activate MEK/ERK signalling. How disparate extracellular signals are translated by MEK/ERK into different cellular functions remains obscure. Originally identified in yeast, scaffold proteins are now recognized to contribute to the specificity of MEK/ERK pathways in mammalian cells. These scaffolds include KSR (kinase suppressor of Ras), β-arrestin, MEK partner-1, Sef and IQGAP1. Scaffolds organize multiprotein signalling complexes. This targets MEK/ERK to specific substrates and facilitates communication with other pathways, thereby mediating diverse functions. The adaptor proteins regulate the kinetics, amplitude and localization of MEK/ERK signalling, providing an efficient mechanism that enables an individual extracellular stimulus to promote a specific biological response.
Spatio-temporal regulation of mitogen-activated protein kinase (MAPK) signalling by protein phosphatases
Authors: Karlsson M. , Mandl M. , Keyse S.M.
Published: October 2006

ERK (extracellular-signal-regulated kinase) is a MAPK (mitogen-activated protein kinase), which regulates diverse physiological functions including cell proliferation, differentiation, transformation and survival. It is now clear that in addition to the duration and magnitude of signalling through this MAPK pathway, the spatial restriction of MAPK activity plays a key role in determining the physiological outcome of signalling. Recent work has led to the discovery of MAPK-binding proteins, which contain either nuclear localization signals or nuclear export signals. These include MAPK activators and specific protein phosphatases, which may act to both regulate MAPK activity and the subcellular localization of their substrate. This represents a mechanism by which signalling in response to extracellular stimuli may be modulated in terms of both magnitude/duration and spatial restriction thus allowing differential access of the activated MAPK to target proteins and the interpretation of this information by cells to determine an appropriate physiological response.
The GAP1 family of GTPase-activating proteins: spatial and temporal regulators of small GTPase signalling
Authors: Yarwood S. , Bouyoucef-Cherchalli D. , Cullen P.J. , Kupzig S.
Published: October 2006

Ras proteins are binary switches that, by cycling between inactive GDP-bound and active GTP-bound conformations, regulate multiple cellular signalling pathways including those that control cell growth, differentiation and survival. Approximately 30% of all human tumours express Ras-containing oncogenic mutations that lock the protein into a constitutively active conformation. The activation status of Ras is regulated by two groups of proteins: GEFs (guanine nucleotide-exchange factors) bind to Ras and enhance the exchange of GDP for GTP, thereby activating it, whereas GAPs (GTPase-activating proteins) inactivate Ras by binding to the GTP-bound form and enhancing the hydrolysis of the bound nucleotide back to GDP. In this review, we focus on a group of key regulators of Ras inactivation, the GAP1 family of Ras-GAPs. The members of this family are GAP1m, GAP1IP4BP, CAPRI (Ca2+-promoted Ras inactivator) and RASAL (Ras-GTPase-activating-like protein) and, as we will discuss, they are emerging as important modulators of Ras and small GTPase signalling that are subject to regulation by a diverse array of events and second messenger signals.
Synaptic plasticity of kainate receptors
Authors: Mellor J.R.
Published: October 2006

Synaptic plasticity of ionotropic glutamate receptors has been extensively studied with a particular focus on the role played by NMDA (N-methyl-D-aspartate) receptors in the induction of synaptic plasticity and the subsequent movement of AMPA (α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) receptors. The third subtype of ionotropic glutamate receptor, kainate receptors, has not been studied to the same extent, but recent evidence shows that these receptors also exhibit synaptic plasticity in response to activity. There is also a growing body of data on the mechanisms underlying kainate receptor trafficking and the proteins they interact with. This review summarizes the current state of knowledge on this topic, focusing on the evidence for the removal or insertion of functional kainate receptors in response to synaptic activity and the cellular mechanisms that underlie this regulation of neuronal kainate receptor function.
F1-ATPase: a highly coupled reversible rotary motor
Authors: Iino R. , Noji H.
Published: October 2006

F1 (F1-ATPase) is a highly coupled rotary molecular motor and hydrolyses three ATP molecules per turn (3 ATP/turn). Recently, we have developed femtolitre reaction chamber arrays for highly sensitive measurement of biological reactions. By combining this technique with the rotating magnetic tweezers, the coupling ratio of the reverse reaction, ATP synthesis catalysed by single F1 molecules, has been investigated. The low coupling ratio of 10% (0.3 ATP/turn), catalysed by the α3β3γ subcomplex of F1, was significantly improved to 77% (2.3 ATP/turn) after reconstitution of the ϵ subunit. This result revealed the novel function of the ϵ subunit as a coupling factor of ATP synthesis catalysed by F1. The possible mechanism for highly coupled ATP synthesis supported by the ϵ subunit is discussed.
Rehearsing the Partition: Gendered Violence in aur Kitne Tukde
Authors: Menon Jisha
Published: October 2006

This article argues that the specifically sexual nature of the political violence of the 1947 Partition of British India installs women's bodies as unambiguously sexed and ethnic. Through an analysis of Kirti Jain's 2001 theatre production of Aur Kitne Tukde (How Many Fragments?), I consider how Hindus, Muslims and Sikhs appropriate colonialist and nationalist ideologies surrounding the notion of ‘woman’ as repository of cultural value. The women in Jain's play are not a priori subjects who experience violence but rather the experience of violence makes (and unmakes) them as gendered, ethnic and national subjects. I argue that they come into subjecthood after a violent objectification and are re-constituted by their experience of national and sexual violence. The performance of nationalism – through embodied acts of sexual violence, conversion, martyrdom and state violence – is enacted upon female bodies that are transformed into political artefacts. I ask how bodies are staged and commodified by acts of political violence and argue that marking female bodies through acts of political violence constitutes a mode of transcription to communicate with other men that will encounter this body.
The HotBox: A Visual User Interface to Medical Data
Authors: Ward Richard C , Pouchard Line C , Beckerman Barbara G , Dickson Stewart P
Published: October 2006

The Defense Advanced Research Projects Agency Virtual Soldier Project recently investigated methods to predict outcomes from penetrating wounds based on comparison of complex mathematical models and clinical data including baseline X-ray computed tomography and post-wound imaging. A need of the project was to correlate three-dimensional anatomy to extensive information, including pathophysiology of the wounded soldier, using the anatomical geometry as an interface. To address this need, Oak Ridge National Laboratory developed the HotBox, a user interface that links a given point in space (a voxel) to the structural knowledge ontology describing the anatomy at that location. In addition, the HotBox links the location to the individual's physiological state (vital signs) and a description of the wound. The implementation and use of the HotBox is explained and the implications for the future of medical records, pre-surgical planning, image-guided surgery, and post-surgical treatment and rehabilitation are discussed.
Determination of the effective parameters of a metamaterial by field summation method
Authors: Lerat J.-M. , Malléjac N. , Acher O.
Published: October 2006

A field summation method is used to determine the effective ε and μ of metamaterial structures. The numerical implementation of this method using commercial software is comprehensively described. The field summation method is shown to predict accurately the reflection and transmission coefficients of thin slabs of metamaterials. For thicker slabs, it is shown that any homogenization approach should be flawed. It is established that the limitations for the homogenization approach are not only simply related to the size of the patterns and unit cell but also to the resonance bandwidth of individual scatterers. To support this view, metamaterials made of patterns with limited conductivity are investigated. It is shown that a homogenization approach is adequate on composite made of patterns with larger resonance bandwidth. Field summation method provides good indications on the validity of a homogenization approach and then leads to satisfactory values for the effective ε and μ.
Nonvolatile hydrogenated-amorphous-silicon thin-film-transistor memory devices
Authors: Kuo Yue , Nominanda Helinda
Published: October 2006

The floating gate n-channel amorphous-silicon thin-film transistor nonvolatile memory device, which includes an a-Si:H layer embedded in the SiNx gate dielectric layer, has been prepared and studied. The transistor’s hysteresis of transfer characteristic curves has been used to demonstrate its memory function. A steady threshold voltage change between the “0” and “1” states has been achieved. A large charge retention time of >3600s with the “write” and “erase” gap of 0.5V has been detected. This kind of device brings additional functions to the a-Si:H thin-film transistors, which can expand its application into various areas.
Hydrodynamics of an endothermic gas with application to bubble cavitation
Authors: Lutsko James F.
Published: October 2006

The hydrodynamics for a gas of hard spheres which sometimes experience inelastic collisions resulting in the loss of a fixed, velocity-independent, amount of energy Δ is investigated with the goal of understanding the coupling between hydrodynamics and endothermic chemistry. The homogeneous cooling state of a uniform system and the modified Navier-Stokes equations are discussed and explicit expressions given for the pressure, cooling rates, and all transport coefficients for D dimensions. The Navier-Stokes equations are solved numerically for the case of a two-dimensional gas subject to a circular piston so as to illustrate the effects of the enegy loss on the structure of shocks found in cavitating bubbles. It is found that the maximal temperature achieved is a sensitive function of Δ with a minimum occurring near the physically important value of Δ∼12000K∼1eV.
Theoretical study of the CS2+ dication
Authors: Šedivcová T. , Špirko V. , Fišer J.
Published: October 2006

The potential energy and spin-orbit coupling functions of 11 lowest electronic states of CS2+ dication have been calculated using internally contracted multireference configuration method. Using these functions, the positions and widths of the corresponding vibronic levels have been evaluated by means of the stabilization and log-phase-amplitude methods. The states governing the second step in the sequential pathway CS23+→S++CS2+→S++C++S+ of the overall three-body Coulomb explosion of CS23+ have been determined.
Inclusion of inversion symmetry in centroid molecular dynamics: A possible avenue to recover quantum coherence
Authors: Huh Yoonjung , Roy Pierre-Nicholas
Published: October 2006

Inversion symmetry is included in the operator formulation of the centroid molecular dynamics (CMD). This work involves the development of a symmetry-adapted CMD (SA-CMD), here particularly for symmetrization and antisymmetrization projections. A symmetry-adapted quasidensity operator, as defined by Blinov and Roy [J. Chem. Phys. 115, 7822 (2001)], is employed to obtain the centroid representation of quantum mechanical operators. Numerical examples are given for a single particle confined to one-dimensional symmetric quartic and symmetric double-well potentials. Two SA-CMD simulations are performed separately for both projections, and centroid position autocorrelation functions are obtained. For each projection, the quality of the approximation as well as the accuracy are similar to those of regular CMD. It is shown that individual trajectories from two separate SA-CMD simulations can be properly combined to recover trajectories for Boltzmann statistics. Position autocorrelation functions are compared to the exact quantum mechanical ones. This explicit account of inversion symmetry provides a qualitative improvement on the conventional CMD approach and allows the recovery of some quantum coherence.
Atomic scale study of oxidation of hafnium: Formation of hafnium core and oxide shell
Authors: Govindaraj R. , Sundar C. S. , Kesavamoorthy R.
Published: October 2006

Perturbed angular correlation studies on hafnium foil subjected to annealing in oxygen atmosphere show that there exists three distinct Hf sites which are identified as probe atoms associated with hafnium metallic clusters, hafnium oxide, and oxygen deficient oxide zones. Kinetics of oxidation has been studied. Variations of quadrupole parameters with annealing treatments show that there is a formation of hafnium core surrounded by a shell of hafnium oxide. Inner hafnium core and outer oxide shell are identified to be separated by oxygen deficient oxide zones. Results suggest that annealing at elevated temperatures leads to a reduction in the size of hafnium cores to submicron, surrounded predominantly by well grown hafnium oxide. Occurrence of nanometallic hafnium clusters in the hafnium oxide matrix has been identified by low frequency laser Raman scattering studies.
Infrared predissociation spectroscopy of ammonia cluster cations (NH3)n+ (n=2–4) produced by vacuum-ultraviolet photoionization
Authors: Matsuda Yoshiyuki , Mori Mayumi , Hachiya Masaki , Fujii Asuka , Mikami Naohiko
Published: October 2006

Infrared predissociation spectroscopy of vacuum ultraviolet-pumped ion (IRPDS-VUV-PI) is performed on ammonia cluster cations (NH3)n+ (n=2–4) that are produced by VUV photoionization in supersonic jets. The structures of (NH3)2+ and (NH3)4+ are determined through the observation of infrared spectra and vibrational calculations based on ab initio calculations at the MP2∕6-31G** and 6-31++G** levels. (NH3)2+ is found to be of the “hydrogen-transferred” form having the (H3N+–H⋯NH2) composition. In contrast, (NH3)4+ exhibits the “head-to-head” dimer cation (H3N⋯NH3)+ core structure, where the positive charge is shared between two ammonia molecules in the core, and two other molecules are hydrogen bonded onto the core. An unequivocal assignment of the infrared spectrum of (NH3)3+ has not been achieved, because the presence of two isomeric structures could be suggested by the observed spectrum and theoretical calculations.
A compact quantum model of nanoscale double-gate metal-oxide-semiconductor field-effect transistor for high frequency and noise simulations
Authors: Lázaro A. , Nae B. , Moldovan O. , Iñiguez B.
Published: October 2006

In this paper, we present an analytical model for high frequency and microwave noise model of nanoscale double-gate metal-oxide-semiconductor field-effect transistor. The model is based on a compact model for charge quantization within the channel and it includes overshoot velocity effects. Radio-frequency and noise performances are calculated using an active transmission line method. A comparison is made between classical and quantum charge control and between drift diffusion and hydrodynamic models.
A radio-frequency sheath boundary condition and its effect on slow wave propagation
Authors: D’Ippolito D. A. , Myra J. R.
Published: October 2006

Predictive modeling of radio-frequency wave propagation in high-power fusion experiments requires accounting for nonlinear losses of wave energy in the plasma edge and at the wall. An important mechanism of “anomalous” power losses is the acceleration of ions into the walls by rf sheath potentials. Previous work computed the “sheath power dissipation” non-self-consistently by postprocessing fields obtained as the solution of models which did not retain sheaths. Here, a method is proposed for a self-consistent quantitative calculation of sheath losses by incorporating a sheath boundary condition (SBC) in antenna coupling and wave propagation codes. It obtains the self-consistent sheath potentials and spatial distribution of the time-averaged power loss in the solution for the linear rf fields. It can be applied for ion cyclotron and (in some cases) lower hybrid waves. The use of the SBC is illustrated by applying it to the problem of an electron plasma wave propagating in a waveguide. This model problem is relevant to understanding the low heating efficiency in direct ion-Bernstein wave launch. Implications for calculating sheath voltages driven by fast-wave antennas are also discussed.
Reentrant wetting transition on surfactant solution surfaces
Authors: Cheng Y. , Ye X. , Huang X. D. , Ma H. R.
Published: October 2006

The wetting of polydimethylsiloxane oil drops on the surfaces of anionic surfactant sodium dodecylsulfate solutions is studied systematically by changing the bulk surfactant concentration. The wetting state changes from complete wetting to pseudopartial wetting at 0.3cmc (critical micelle concentration) surfactant concentration and there is a reentrant transition back to complete wetting at 1.4cmc. The measured free energy is consistent with the prediction of the wetting theory. The interaction potential minimum of the two surfaces of the oil film disappears at the reentrant point, which is speculated to be an effect of micelle formation in the solution.
Analysis of thermal aberrations in a high average power single-stage Ti:sapphire regenerative chirped pulse amplifier: Simulation and experiment
Authors: Ramanathan Vidya , Lee Jinho , Xu Shengbo , Wang Xiaoming , Williams Luke , Malphurs William , Reitze D. H.
Published: October 2006

We present a systematic investigation of thermal loading effects in single-stage high average power regenerative chirped pulse amplifiers based on Ti:sapphire. Using finite element analysis (FEA), we compute the temperature distributions, optical path deformations (OPDs), and corresponding thermal focal lengths for a variety of pumping conditions. We experimentally characterize thermal aberrations in a regenerative amplifier using a variety of techniques (interferometry, pump-probe thermal lens power, and M2 analysis). We find excellent agreement between the FEA modeling and experimental measurements of OPDs. Our methods allow us to predict the optimal pumping conditions for minimizing thermal aberrations for a variety of geometries and pumping conditions.