bluuebunny/crossref_metadata_2025 huggingface dataset:
Caterpillar regurgitant induces pore formation in plant membranes
Authors: Lühring Hinrich , Nguyen Van Dy , Schmidt Lilian , Röse Ursula S.R.
Published: October 2007

Formation of channel‐like pores in a plant membrane was induced within seconds after application of an aqueous solution containing regurgitant of the insect larvae Spodoptera littoralis. Gated pore currents recorded on the tonoplast of the Charophyte Chara corallina displayed conductances up to several hundred pS. A voltage‐dependent gating reaction supports the assumption that pore‐forming molecules have amphipathic properties. Regurgitant samples separated into masses smaller or larger than 3 kDa were evaluated by patch–clamp and mass spectroscopy. Fractions containing peptides larger than 3 kDa constituted pores of large conductances, peptides smaller than 3 kDa constituted pores of small conductances. Peptide‐free eluates did not constitute conducting pores, indicating that pore‐forming components in regurgitant are membrane‐spanning oligopeptides.
Rabbi Jeruham b. Meshullam, Michael Scot, and the Development of Jewish Law in Fourteenth-Century Spain
Authors: Galinsky Judah D. , Robinson James T.
Published: November 2007

One of the most mysterious and haunting of all medieval halakhic figures must certainly be the fourteenth-century sage Rabbi Jeruham b. Meshullam. During the sixteenth century, he was known as “Tamiri”—“the concealed one”—a moniker given to him by Joseph Karo's heavenly interlocutor, the Maggid. Years later, David Azulai, the eminent eighteenth-century rabbinic bibliographer, reported that “a number of Rabbis who had composed commentaries on his work … were summoned to the heavenly academy [i.e., they died prematurely] or their work was lost.” Even today, scholars who have never opened Jeruham's books are nevertheless aware of the “curse” hanging over the work of this medieval author.
The Battle of Özü—A Survivor's Testimony
Authors: AšČERIĆ-TODD INES
Published: October 2007

In the year 1150 (1737–38) the recorder of the Prophet's Meccan biography by Veysi Üskübi, may God's mercy be upon him, the humble and deficient Defter Kethüdasi Mehmet ibn Mustafa Efendi, was by an imperial order with the army of the Bosnian province at the battle of Özü. On the 14th day of the month of Rebiülevvel of that year, which was a Saturday, the large ammunition store situated in the citadel of the city fortress was hit by a spark of fire and in an instant the citadel was turned upside down, and inside the fortress and on its walls many men, women, and children perished flying into the air and [scattering] on the ground. After this, the next day, on Sunday, all that was left of the army of the aforementioned province, the governor of the abovementioned fortress, his Excellency the Honorable Vizier Yahya Paşa, his household, the people of four Rumeli sancaks, five Janissary regiments from the imperial headquarters, and all of the garrison forces and its inhabitants, together with women and children, by the will of God Almighty all [fell] prisoner to the Muscovite infidel, most of them with their heads uncovered and barefooted…
Family Follies
Authors: POLLARD LISA
Published: October 2007

“The wife: I bet your friends envy you your domestic happiness!” Reprinted with permission of Mohammed Elchamaa.

This cartoon comes from a 1948 edition of the Egyptian periodical Akhir Saʿa. I happened across it in Cairo, as part of some exploratory research into the fate of the female image of the Egyptian nation-state that was so central to the 1919 revolution. In previous inquiries, I had noticed that “lady Egypt” or “mother Egypt” or “Egypt as a woman,” to use historian Beth Baron's expression, lost pride of place in popular periodicals as 1919 gave way to nominal independence and nation building. By the late 1920s, cartoon and caricature space was more frequently dedicated to men engaged in laying the foundations of new political, legal, and educational systems, as well as erecting the buildings that would house them. Throughout the 1930s, political caricatures also frequently lampooned prominent Egyptian men for their behavior in the institutions that they had been active in creating. In the popular press, the reified female figure of the Egyptian nation was all but usurped by the men who built the state (and who seemed determined to keep Egyptian women out of the body politic).
Jordanian Employment in the Aqaba Labor Market
Authors: AL-EMYAN MOZFI M. , ABU-HAMATTEH ZIAD S. , AL-AZZAM FAROOQ A.
Published: October 2007

This table shows the employment of Jordanians across industrial, educational, and occupational groups as a percentage of total employment in 2003. Note that the three major industries (in order) are public administration/social services; trade, including hotels and restaurants; and manufacturing. Almost 50 percent of Jordanian workers had less than a secondary education, and almost 50 percent of all employees fell into three occupational groups: service, shop, and market sales; craft and related trades; and elementary occupations.
Question: How Have Internet Developments Changed What—or How—You Study about the Middle East? Pensée 1: The Excessive Charms of the Internet
Authors: TARAKI LISA
Published: October 2007

The most obvious answer to this question would be to underline the huge impact of the Internet on research on the Middle East: the speed with which material is circulated among colleagues, reviewers, and editors; the increasing availability of documents and materials; the ease of access to scholarly work through online databases; the availability of scholarly forums (such as H-Net) for exchanging information and views; and a long list of other benefits. My own correspondence with a publisher and some journal editors in the past few months is a case in point: a seven-month strike declared by postal and other public-sector workers to protest the Palestinian Authority's nonpayment of salaries stopped all mail services to and from the occupied territories. Without the Internet (and private mail carriers) I certainly could not have published what I did manage to publish in these turbulent times. There are more substantive implications of Internet developments for scholars of the Middle East, and I would like to focus on two of them in the short space allowed here.
Pensée 3: New Media in the Arab World
Authors: KUTTAB DAOUD
Published: October 2007

The reform process in the Arab world has been largely stagnant. Political change is moving at a very slow pace despite claims to the contrary by autocratic leaders. Whereas change from top to bottom is slow and at times nonexistent, change at the grass roots is another matter. For one thing, the population is becoming younger and younger, and this young generation of Arabs is being exposed to many new trends and communication tools, of which many older generation leaders are for the most part not even aware.
Pensée 4: Striking New State–Society Bargains over the Internet
Authors: ANDERSON JON W.
Published: October 2007

Not long ago a MESA Bulletin reader objected to introducing coverage of the Internet, saying that there were few Middle East studies online. However, you do find Middle Easterners. With increasingly accessible technology, there are thousands of websites that are added to listservs and now supplemented by blogs from, by, and about Middle Easterners. The trend has been from witness to participant. Yet the subjective register of the Internet in Middle East and North Africa is often a new example of exceptionalism: less free than in the West, less extensive than in the Far East, slow to grow and stunted when it does, with limited access and high costs that confine it demographically and culturally, not to mention politically. That is also what most comparative measures tell, but those do not measure what is happening. Early interest a decade ago has subsequently faded—or phased—into something more interesting than another story of absences.
DISPLACING DHIMMĪ, MAINTAINING HOPE: UNTHINKABLE COPTIC REPRESENTATIONS OF FATIMID EGYPT
Authors: Shenoda Maryann M.
Published: October 2007

It is a strange interaction that occurs between Muslim and Copt in the passage above, which was written in the 11th century and set in the 10th century. What might be proven by such a debate over a dog's religion? What is more, why record such an incident in a church-sanctioned history? Because the dog cannot speak, there must be another way to know whether it is Christian or Muslim (for those are the only two possibilities in the story). In the end it is through the dog's ritual practice—drinking wine or eating meat or not drinking wine or not eating meat—rather than through the dog's outward proclamation of religious affiliation that the Copt and the Muslim come to an agreement about what distinguishes one from the other. Ritual practice, action such as abstinence from meat or alcohol that demonstrates adherence to particular religious ideas, distinguishes Copt from Muslim even in the absence of a shared spoken language to communicate that difference. Copts and Muslims in Egypt, the story teaches, are different, and they may be distinguished even by something as minor as their food and drink.
A “YOUNG TURK” ISLAMIC INTELLECTUAL: FILIBELI AHMED HILMI AND THE DIVERSE INTELLECTUAL LEGACIES OF THE LATE OTTOMAN EMPIRE
Authors: Bein Amit
Published: October 2007

Among the late Ottoman thinkers and writers who laid the foundations of intellectual life in modern Turkey, Filibeli Ahmed Hilmi (1865–1914) is a prominent figure. His intellectual legacy survived the destruction of the Ottoman Empire and the founding of the Republic of Turkey. Virtually all his books have been republished in recent years in simplified modern Turkish versions accessible to present-day readers, and some have also been the subject of academic studies. His oeuvre includes dozens of historical, philosophical, theological, and political works, as well as novels, poems, satirical pieces, and plays. All were produced in a six-year period, between the Young Turk Revolution of 1908 and his death by poisoning in 1914. The overtly modernist underpinnings of his works on the one hand, and his Sufi piety and firm rejection of materialism and positivism on the other, have earned him recognition as an early exponent of a modernist, nonliteralist Islamic agenda of a kind that has been conspicuous in a variety of Turkish-Islamic movements in recent decades. His untimely death, later attributed to a Freemason–Zionist conspiracy, added further to his mystique in some Islamic circles. Modernist yet deeply devout, Islamist yet uninterested in scripturalist paths of religious revival, Ahmed Hilmi stands out as a representative of an important intellectual trend that has often been overlooked in studies of the late Ottoman period.
Experimental investigation of turbulent density fluctuations and noise generation from heated jets
Authors: PANDA J.
Published: October 2007

Low-frequency noise sources in heated single-stream jets were identified by cross-correlating turbulent density fluctuations ρ′ with the far-field sound pressure fluctuations p′. The turbulent density fluctuations were measured by a molecular Rayleigh-scattering technique. For a fixed jet velocity Uj, the normalized correlation coefficient 〈ρ′; p′〉/(ρ′rmsp′rms is found to increase progressively with an increase in the plume temperature (subscript rms stands for root-mean-square). The result indicates an improvement of the noise radiation efficiency with heating. Directly measured noise spectra from fixed velocity jets with increasing temperature ratio show confusing trends. However, if such spectra are normalized by theplume density, then a consistent trend of increasing noise level with increased plume temperature emerges. The increased noise is the most prominent at the low-frequency end, consistent with the correlation data. The effect of increasing jet velocity keeping the plume temperature constant was also studied. The correlation coefficients were found to improve significantly with velocity; a result consistent with prior observation from unheated jets. Additional findings on the time-averaged density variations and the changes in the air density fluctuations with increasing plume temperature are also discussed.
Transient natural ventilation of a room with a distributed heat source
Authors: FITZGERALD SHAUN D. , WOODS ANDREW W.
Published: October 2007

We report on an experimental and theoretical study of the transient flows which develop as a naturally ventilated room adjusts from one temperature to another. We focus on a room heated from below by a uniform heat source, with both high- and low-level ventilation openings. Depending on the initial temperature of the room relative to (i) the final equilibrium temperature and (ii) the exterior temperature, three different modes of ventilation may develop. First, if the room temperature lies between the exterior and the equilibrium temperature, the interior remains well-mixed and gradually heats up to the equilibrium temperature. Secondly, if the room is initially warmer than the equilibrium temperature, then a thermal stratification develops in which the upper layer of originally hot air is displaced upwards by a lower layer of relatively cool inflowing air. At the interface, some mixing occurs owing to the effects of penetrative convection. Thirdly, if the room is initially cooler than the exterior, then on opening the vents, the original air is displaced downwards and a layer of ambient air deepens from above. As this lower layer drains, it is eventually heated to the ambient temperature, and is then able to mix into the overlying layer of external air, and the room becomes well-mixed. For each case, we present new laboratory experiments and compare these with some new quantitative models of the transient flows. We conclude by considering the implications of our work for natural ventilation of large auditoria.
Numerical investigation of the tone noise mechanism over laminar airfoils
Authors: DESQUESNES G. , TERRACOL M. , SAGAUT P.
Published: October 2007

This paper presents the first numerical investigation via direct numerical simulation of the tone noise phenomenon occurring in the flow past laminar airfoils. This phenomenon corresponds to the radiation of discrete acoustic tones in some specific flow conditions, and has received much attention since the 1970s, and several experimental studies have been carried out to identify and understand the underlying physical mechanisms. However, several points remain to be clarified in order to provide a complete explanation of its origin. The flow around a two-dimensional NACA0012 airfoil is considered in order to have a deeper understanding of the tone noise phenomenon. Consistently with previous experimental studies, it is shown that depending on the Reynolds number and angle of attack, two different types of acoustic spectrum are observed: one which exhibits a broadband contribution with a dominant frequency together with a sequence of regularly spaced discrete frequencies, while the other one is only characterized by a simple broadband contribution. The first configuration is typical of the tone noise phenomenon. The present work shows that in this case, the mean flow on the pressure side of the airfoil exhibits a separation bubble near the trailing edge and the main tone frequency is close to the most amplified frequency of the boundary layer. The mechanism proposed in previous works for the main tone generation – which implies the existence of a separation bubble at the pressure side – is therefore validated by numerical simulation. On the other hand, the analysis of the suction side boundary layer reveals that there is no separation and that the most amplified frequency is different from the main tonal one. However, the suction side boundary layer is highly receptive to the tone frequency. Finally, an original explanation for the existence of the secondary discrete frequencies observed in the radiated pressure spectrum is given. They are associated to a bifurcation of the airfoil wake from a symmetric to a non-symmetric vortex pattern. A possible explanation for the existence of this bifurcation is the interaction between the disturbances which are the most amplified by the suction side boundary layer and those originating in the forcing of the suction side flow by the main tone noise mechanism.
Numerical simulation of the compressible mixing layer past an axisymmetric trailing edge
Authors: SIMON FRANCK , DECK SEBASTIEN , GUILLEN PHILIPPE , SAGAUT PIERRE , MERLEN ALAIN
Published: October 2007

Numerical simulation of a compressible mixing layer past an axisymmetric trailing edge is carried out for a Reynolds number based on the diameter of the trailing edge approximately equal to 2.9 × 106. The free-stream Mach number at separation is equal to 2.46, which corresponds to experiments and leads to high levels of compressibility. The present work focuses on the evolution of the turbulence field through extra strain rates and on the unsteady features of the annular shear layer. Both time-averaged and instantaneous data are used to obtain further insight into the dynamics of the flow. An investigation of the time-averaged flow field reveals an important shear-layer growth rate in its initial stage and a strong anisotropy of the turbulent field. The convection velocity of the vortices is found to be somewhat higher than the estimated isentropic value. This corroborates findings on the domination of the supersonic mode in planar supersonic/subsonic mixing layers. The development of the shear layer leads to a rapid decrease of the anisotropy until the onset of streamline realignment with the axis. Due to the increase of the axisymmetric constraints, an adverse pressure gradient originates from the change in streamline curvature. This recompression is found to slow down the eddy convection. The foot shock pattern features several convected shocks emanating from the upper side of the vortices, which merge into a recompression shock in the free stream. Then, the flow accelerates and the compressibility levels quickly drop in the turbulent developing wake. Some evidence of the existence of large-scale structures in the near wake is found through the domination of the azimuthal mode m = 1 for a Strouhal number based on trailing-edge diameter equal to 0.26.
Experiments on gravitational phase separation of binary immiscible fluids
Authors: SATO MISUZU , SUMITA IKURO
Published: October 2007

We conduct experiments on gravitational phase separation of binary immiscible fluids using an oil–water mixture and study how the volumetric and viscosity ratios of the two phases control the separation process. First, we change the volumetric fraction of the two phases. We find that the initial phase separation rate depends strongly on the volumetric ratio of the two phases, and can be modelled by a buoyancy-driven permeable flow using the Blake–Kozeny–Carman permeability formula. Next, we change the viscosity ratios of the two fluids, and we find that there are two distinct regimes with different styles of phase separation. Small viscosity ratio (<100) cases are characterized by a sharp lower boundary and a vertically homogeneous mixture layer. On the other hand, high viscosity ratio (>100) cases are characterized by a diffuse lower boundary and a large vertical gradient of porosity. A polyhedral foam structure develops at the top of the mixture layer which is slow to rupture and to transform into a uniform oil layer. These differences can be interpreted to arise from a faster coalescence rate relative to the separation rate at high viscosity ratios. We simultaneously measured electrical resistivity in order to monitor the temporal change of the mean porosity in the mixture layer. The measurements were found to be consistent with the visual observation.
Buoyancy-driven variable-density turbulence
Authors: LIVESCU D. , RISTORCELLI J. R.
Published: October 2007

Buoyancy-generated motions in an unstably stratified medium composed of two incompressible miscible fluids with different densities, as occurs in the variable-density Rayleigh–Taylor instability, are examined using direct numerical simulations. The non-equilibrium homogeneous buoyantly driven problem is proposed as a unit problem for variable density turbulence to study: (i) the nature of variable density turbulence, (ii) the transition to turbulence and the generation of turbulence by the conversion of potential to kinetic energy; (iii) the role of non-Boussinesq effects; and (iv) a parameterization of the initial conditions by a static Reynolds number. Simulations are performed for Atwood numbers up to 0.5 with root mean square density up to 50% of the mean density and Schmidt numbers, 0.1 ≤ Sc ≤ 2. The benchmark problem has been designed to have the largest mass flux possible and is, in this configuration, the maximally unstable non-equilibrium flow possible. It is found that the mass flux, owing to its central role in the conversion of potential to kinetic energy, is probably the single most important dynamical quantity to predict in lower-dimensional models. Other primary findings include the evolution of the mean pressure gradient: during the non-Boussinesq portions of the flow, the evolution of the mean pressure gradient is non-hydrostatic (as opposed to a Boussinesq fluid) and is set by the evolution of the specific volume pressure gradient correlation. To obtain the numerical solution, a new pressure projection algorithm which treats the pressure step exactly, useful for simulations of non-solenoidal velocity flows, has been constructed.
Weakly turbulent laws of wind-wave growth
Authors: BADULIN SERGEI I. , BABANIN ALEXANDER V. , ZAKHAROV VLADIMIR E. , RESIO DONALD
Published: October 2007

The theory of weak turbulence developed for wind-driven waves in theoretical works and in recent extensive numerical studies concludes that non-dimensional features of self-similar wave growth (i.e. wave energy and characteristic frequency) have to be scaled by internal wave-field properties (fluxes of energy, momentum or wave action) rather than by external attributes (e.g. wind speed) which have been widely adopted since the 1960s. Based on the hypothesis of dominant nonlinear transfer, an asymptotic weakly turbulent relation for the total energy ϵ and a characteristic wave frequency ω* was derived

The self-similarity parameter αss was found in the numerical duration-limited experiments and was shown to be naturally varying in a relatively narrow range, being dependent on the energy growth rate only.

In this work, the analytical and numerical conclusions are further verified by means of known field dependencies for wave energy growth and peak frequency downshift. A comprehensive set of more than 20 such dependencies, obtained over almost 50 years of field observations, is analysed. The estimates give αss very close to the numerical values. They demonstrate that the weakly turbulent law has a general value and describes the wave evolution well, apart from the earliest and full wave development stages when nonlinear transfer competes with wave input and dissipation.
Experimental investigation into the routes to bypass transition and the shear-sheltering phenomenon
Authors: HERNON DOMHNAILL , WALSH EDMOND J. , McELIGOT DONALD M.
Published: October 2007

The objective of this investigation is to give experimental support to recent direct numerical simulation (DNS) results which demonstrated that in bypass transition the flow first breaks down to turbulence on the low-speed streaks (or so-called negative jets) that are lifted up towards the boundary-layer edge region. In order to do this, wall-normal profiles of the streamwise fluctuation velocity are presented in terms of maximum positive and negative values over a range of turbulence intensities (1.3–6%) and Reynolds numbers for zero pressure gradient flow upstream of, and including, transition onset. For all turbulence intensities considered, it was found that the peak negative fluctuation velocity increased in magnitude above the peak positive fluctuations and their positions relative to the wall shifted as transition onset approached; the peak negative value moved towards the boundary-layer edge and the peak positive value moved toward the wall. An experimental measure of the penetration depth (PD) of free-stream disturbances into the boundary layer has been gained through the use of the skewness function. The penetration depth (measured from the boundary-layer edge) scales as PD ∝ (ω Rexτw)−0.3), where ω is the frequency of the largest eddies in the free stream, Rex is the Reynolds number of the flow based on the streamwise distance from the leading edge and τw is the wall shear stress. The parameter dependence demonstrated by this scaling compares favourably with recent solutions to the Orr–Sommerfeld equation on the penetration depth of disturbances into the boundary layer. The findings illustrate the importance of negative fluctuation velocities in the transition process, giving experimental support to suggestions from recent DNS predictions that the breakdown to turbulence is initiated on the low-speed regions of the flow in the upper portion of the boundary layer. The representation of pre-transitional disturbances in time-averaged form is shown to be inadequate in elucidating which disturbances grow to cause the breakdown to turbulence.
The near-shore behaviour of shallow-water waves with localized initial conditions
Authors: PRITCHARD DAVID , DICKINSON LAURA
Published: October 2007

We consider the behaviour of solutions to the nonlinear shallow-water equations which describe wave runup on a plane beach, concentrating on the behaviour at and just behind the moving shoreline. We develop regular series expansions for the hydrodynamic variables behind the shoreline, which are valid for any smooth initial condition for the waveform. We then develop asymptotic descriptions of the shoreline motion under localized initial conditions, in particular a localized Gaussian waveform: we obtain estimates for the maximum runup and drawdown of the wave, for its maximum velocities and the forces it is able to exert on objects in its path, and for the conditions under which such a wave breaks down. We show how these results may be extended to include initial velocity conditions and initial waveforms which may be approximated as the sum of several Gaussians. Finally, we relate these results tentatively to the observed behaviour of a tsunami.
Revisiting Batchelor's theory of two-dimensional turbulence
Authors: DRITSCHEL DAVID G. , TRAN CHUONG V. , SCOTT RICHARD K.
Published: October 2007

Recent mathematical results have shown that a central assumption in the theory of two-dimensional turbulence proposed by Batchelor (Phys. Fluids, vol. 12, 1969, p. 233) is false. That theory, which predicts a χ2/3k−1 enstrophy spectrum in the inertial range of freely-decaying turbulence, and which has evidently been successful in describing certain aspects of numerical simulations at high Reynolds numbers Re, assumes that there is a finite, non-zero enstrophy dissipation χ in the limit of infinite Re. This, however, is not true for flows having finite vorticity. The enstrophy dissipation in fact vanishes.

We revisit Batchelor's theory and propose a simple modification of it to ensure vanishing χ in the limit Re → ∞. Our proposal is supported by high Reynolds number simulations which confirm that χ decays like 1/ln Re, and which, following the time of peak enstrophy dissipation, exhibit enstrophy spectra containing an increasing proportion of the total enstrophy 〈ω2〉/2 in the inertial range as Re increases. Together with the mathematical analysis of vanishing χ, these observations motivate a straightforward and, indeed, alarmingly simple modification of Batchelor's theory: just replace Batchelor's enstrophy spectrum χ2/3k−1 with 〈ω2〉 k−1 (ln Re)−1).
Nonlinear three-dimensional interfacial flows with a free surface
Authors: PĂRĂU E. I. , VANDEN-BROECK J.-M. , COOKER M. J.
Published: October 2007

A configuration consisting of two superposed fluids bounded above by a free surface is considered. Steady three-dimensional potential solutions generated by a moving pressure distribution are computed. The pressure can be applied either on the interface or on the free surface. Solutions of the fully nonlinear equations are calculated by boundary-integral equation methods. The results generalize previous linear and weakly nonlinear results. Fully localized gravity–capillary interfacial solitary waves are also computed, when the free surface is replaced by a rigid lid.
Vorticity organization in the outer layer of turbulent channels with disturbed walls
Authors: FLORES OSCAR , JIMÉNEZ JAVIER , DEL ÁLAMO JUAN C.
Published: October 2007

The vortex clusters in the turbulent outer region of rough- and smooth-walled channels, and their associated velocity structures, are compared using data from numerical experiments at friction Reynolds numbers Reτ ≤ 674. The results indicate that the roughness of the wall does not affect their properties, particularly the existence of wall-detached and wall-attached populations, and the self-similar size distribution of the latter. The average flow field conditioned to the attached clusters reveals similar conical structures of low streamwise velocity for the rough- and smooth-walled cases, which eventually grow into the global modes previously identified from spectral analysis. We conclude that the vortex clusters of the turbulent outer region either originate away from the wall, or quickly forget their origin, in agreement with Townsend's similarity hypothesis.
Effect of surfactants on the inertialess instability of a two-layer film flow
Authors: GAO PENG , LU XI-YUN
Published: October 2007

The effect of insoluble surface and interfacial surfactants on the inertialess instability of a two-fluid film flow down an inclined plane is investigated based on a normal mode analysis. The results reveal that the inertialess instability of relatively long waves can be predominantly weakened by a surface surfactant and enhanced by an interfacial surfactant. For sufficiently large viscosity ratio of the upper layer to the lower one, a destabilizing influence of the surface surfactant is also detected; this is thus a rare example demonstrating the possible destabilizing effect of the surfactant on the flow with a free surface. When the upper layer is less viscous and hence the instability due to the viscosity stratification disappears, a new instability can be triggered by the presence of an interfacial surfactant. Both the surfactants on the surface and the interface can stabilize or destabilize the short-wave instabilities, which occur for negligible surface and interfacial tensions.
How Modern Is an Antimodernist Movement? The Emergence of Hasidic Politics in Congress Poland
Authors: Wodziński Marcin
Published: November 2007

The various efforts to reform Jewish society in Poland from the late eighteenth century on elicited reactions among the representatives of Jewish society, both among those who supported the reforms and among others, much more numerous, who were less favorably inclined toward reform. The hasidim were, of course, among the latter. All the reforms affected the hasidim, just as they did other members of the community, but certain actions directed against their movement as such affected them specifically. It seems natural, therefore, that hasidim were not simply passive victims of the deeds undertaken by the central and regional organs of the state. It would be hard to expect otherwise because, after all, the hasidim were a party most interested in the favorable resolution of antihasidic government investigations.
Tehran's Unmined Archive of Kurdish Jewry: A Field Report
Authors: Dehqan Mustafa
Published: November 2007

This brief article offers an overview of the various Kurdo-Jewish records preserved in Tehran in the Iranian Parliament Records archives. The documents reflect the perspectives of Jews and non-Jews alike and were originally reported by Kurdish officials of the Jewish colonies in Iranian Kurdistan, by Jewish senators of the National Parliament of Iran, as well as by Kurdish peasants of Kurdistan. Most of the documents are in Persian, with the exception of perhaps nine in French stemming from Westernized Jewish circles.
The impact of the Scandinavian Monetary Union on financial market integration
Authors: Øksendal Lars Fredrik
Published: November 2007

In the period from 1877 until the outbreak of World War I, Sweden, Denmark and Norway constituted a currency area – the Scandinavian Monetary Union (SMU). They shared the same unit of account, the gold krone. Both full-bodied gold coins and token coins of the three countries served as legal tender and circulated freely within the union. Initially set up to preserve the traditional circulation of neighbouring coins in the border regions, the central bank cooperation was extended to a mutual settlement mechanism (1885) and later reciprocal acceptance of notes at par (1901). A desire for economic integration was present under the surface of this practical approach, mirroring the predominant liberal worldview of the 1870s. For instance, the Norwegian government saw a common coinage as an instrument for ‘knitting together the three nations to a single commercial territory’. In the parliamentary debate on Norwegian entry into the union a supporter argued that ‘the real objective of unity in coin had to be to bring the countries closer together’. Thus, from the outset, the SMU was a combination of practical arrangements and lofty ambitions.
Cluster observations of waves in the whistler frequency range associated with magnetic reconnection in the Earth's magnetotail
Authors: Wei X. H. , Cao J. B. , Zhou G. C. , Santolík O. , Rème H. , Dandouras I. , Cornilleau‐Wehrlin N. , Lucek E. , Carr C. M. , Fazakerley A.
Published: October 2007

On 21 August 2002 the Cluster spacecraft encountered a quasi‐collisionless magnetic reconnection event when it crossed the plasma sheet. Prior to the southward turning of magnetic field in the tailward flow, the weak whistler waves were first observed. The burst of whistler waves appeared about 30 s earlier than the southward turning. During magnetic reconnection event, the waves in the whistler frequency range were greatly enhanced. For the waves in the reconnection process, those in the higher‐frequency range are mainly quasi‐parallel propagating right‐hand polarized whistler waves, while those in the lower‐frequency range are quasi‐perpendicular propagating linear polarized waves, which may be a superposition of several linearly polarized waves. The combined observations of energetic electrons and waves show that after the southward turning of magnetic field, the waves in the reconnection process are greatly enhanced by energetic electron beams.
Reconstruction of the reconnection rate from Cluster measurements: Method improvements
Authors: Ivanova V. V. , Semenov V. S. , Penz T. , Ivanov I. B. , Sergeev V. A. , Heyn M. F. , Farrugia C. J. , Biernat H. K. , Nakamura R. , Baumjohann W.
Published: October 2007

A remote‐sensing method for reconstructing the reconnection rate and the location of X‐line from single‐spacecraft observations developed recently is extended to a compressible plasma and an asymmetric magnetic field configuration. The method is based on the two‐dimensional analytical model of time‐dependent Petschek‐type magnetic reconnection. The reconstruction technique is applied to a nightside flux transfer event recorded by Cluster spacecraft in the near‐Earth magnetotail on 26 September 2005. The reconnection rate is found to be 3.7–4.8 mV/m; the reconnection distance is around 9–11 Re in the tail.
Effects of Fe spin transition on the elasticity of (Mg, Fe)O magnesiowüstites and implications for the seismological properties of the Earth's lower mantle
Authors: Speziale S. , Lee V. E. , Clark S. M. , Lin J. F. , Pasternak M. P. , Jeanloz R.
Published: October 2007

High‐pressure x‐ray diffraction of (Mg0.80Fe0.20)O at room temperature reveals a discontinuity in the bulk modulus at 40 (±5) GPa, similar to the pressure at which an electronic spin‐pairing transition of Fe2+ is observed by Mössbauer spectroscopy. We determine the zero‐pressure bulk modulus of low‐spin magnesiowüstite to be between KT0 = 136 and 246 GPa, with a pressure derivative (∂KT/∂P)T0 between 5.2 and 3.9. The best fit unit‐cell volume at zero pressure, V0 = 71 (±5) Å3, is consistent with past estimates of the ionic radius of octahedrally‐coordinated low‐spin Fe2+ in oxides. A spin transition at lower‐mantle depths between 1100 and 1900 km (40–80 GPa) would cause a unit‐cell volume decrease (ΔV) of 3.7 (±0.5) to 2.0 (±0.1) percent and bulk sound velocity increase (Δvϕ) of 7.6 (±4) percent at 40 GPa and 7.6 (±1.2) percent at 80 GPa. Even in the absence of a visible seismic discontinuity, we expect the spin transition of iron to imply a correction to current compositional models of the lower mantle, with up to 10 mol percent increase of magnesiowüstite being required to match the seismological data.
The early anthropogenic hypothesis: Challenges and responses
Authors: Ruddiman William F.
Published: October 2007

Ruddiman (2003) proposed that late Holocene anthropogenic intervention caused CH4and CO2increases that kept climate from cooling and that preindustrial pandemics caused CO2decreases and a small cooling. Every aspect of this early anthropogenic hypothesis has been challenged: the timescale, the issue of stage 11 as a better analog, the ability of human activities to account for the gas anomalies, and the impact of the pandemics. This review finds that the late Holocene gas trends are anomalous in all ice timescales; greenhouse gases decreased during the closest stage 11 insolation analog; disproportionate biomass burning and rice irrigation can explain the methane anomaly; and pandemics explain half of the CO2decrease since 1000 years ago. Only ∼25% of the CO2anomaly can, however, be explained by carbon from early deforestation. The remainder must have come from climate system feedbacks, including a Holocene ocean that remained anomalously warm because of anthropogenic intervention.
Improved associated conditions in rapid intensifications of tropical cyclones
Authors: Yang Ruixin , Tang Jiang , Kafatos Menas
Published: October 2007

Rapid intensification (RI) of tropical cyclones (TC) is a major error source in TC intensity forecasting. In order to improve the estimates of RI probability, association rules are used to facilitate the process of mining for candidate sets of conditions. Compared to the relation analysis method, the technique of association rules can simply explore associations among multiple conditions. Our mining results identified a reduced predictor set with fewer factors identified in previous studies but improved RI probabilities. That is, the RI probability with three conditions satisfied: low vertical shear, high humidity, and the TC being in an intensification phase is higher than that with five satisfied conditions including high sea surface temperature and an intensity far away from the maximum potential intensity in addition to the above three.
Source parameters of a M4.8 and its accompanying repeating earthquakes off Kamaishi, NE Japan: Implications for the hierarchical structure of asperities and earthquake cycle
Authors: Uchida Naoki , Matsuzawa Toru , Ellsworth William L. , Imanishi Kazutoshi , Okada Tomomi , Hasegawa Akira
Published: October 2007

We determine the source parameters of a M4.9 ± 0.1 ‘characteristic earthquake’ sequence and its accompanying microearthquakes at ∼50 km depth on the subduction plate boundary offshore of Kamaishi, NE Japan. The microearthquakes tend to occur more frequently in the latter half of the recurrence intervals of the M4.9 ± 0.1 events. Our results show that the microearthquakes are repeating events and they are located not only around but also within the slip area for the 2001 M4.8 event. From the hierarchical structure of slip areas and smaller stress drops for the microearthquakes compared to the M4.8 event, we infer the small repeating earthquakes rupture relatively weak patches in and around the slip area for the M4.8 event and their activity reflects a stress concentration process and/or change in frictional property (healing) at the area. We also infer the patches for the M4.9 ± 0.1 and other repeating earthquakes undergo aseismic slip during their interseismic period.
An RCM projection of soil thermal and moisture regimes for North American permafrost zones
Authors: Sushama L. , Laprise R. , Caya D. , Verseghy D. , Allard M.
Published: October 2007

The fourth‐generation Canadian Regional Climate Model (CRCM4) projected changes to the soil thermal and moisture regimes for the continuous, discontinuous, sporadic and isolated permafrost regions in North America, for the 2041–2070 period with respect to the 1961–1990 base period, for the SRES (Special Report on Emissions Scenarios) A2 scenario are presented. The projections indicate significant increase in the near‐surface soil temperatures for all permafrost zones, with maximum warming for the continuous permafrost zone. No significant changes in the timing of minimum and maximum near‐surface soil temperatures are projected by the CRCM4. However, the distributions of both minimum and maximum temperatures, at the surface and for the various near‐surface soil layers, for the future climate, are significantly different from those for current climate. Intensification of the hydrologic cycle in future climate for the various permafrost zones is projected with important changes to the soil moisture regime, which are reflected in the reduction of the frozen soil moisture content, which in turn increases the deep drainage for all permafrost zones.
Polar rain aurora
Authors: Zhang Yongliang , Paxton Larry J. , Lui Anthony T. Y.
Published: October 2007

Global FUV auroral imagers (IMAGE/SI‐13 and DMSP/SSUSI) observed, for the first time, two similar auroral events in the southern polar cap due to intense (keV) polar rain electrons from the solar wind as observed by DMSP and Geotail. Such an aurora is called polar rain aurora. The polar rain aurora could fill the dayside polar cap initially and developed a dawn‐dusk alignment while they moved anti‐sunward. The associated IMF Bz was mostly southward. The IMF Bx changed from negative to positive for the first event and stayed positive for the second event. The strong IMF By was associated with the two events. The dawn‐dusk alignment of polar rain aurora might be due to the dawn‐dusk aligned magnetic flux tubes in the magnetosheath caused by the dominant IMF By and modulation of the keV electrons by the nonoscillatory drift mirror waves and pitch angle diffusion via the electron cyclotron instability.
Propagation of the overtide M4 through the deep Atlantic Ocean
Authors: Ray Richard D.
Published: November 2007

The nonlinear overtide M4 is generated in shallow waters and is generally no more than a few mm amplitude in the deep ocean. Such small, periodic waves can now be mapped empirically by analyzing the long (15‐year) time series of Topex/Poseidon and Jason‐1 satellite altimetry. In a few locations of the deep Atlantic, M4 amplitudes reach nearly 10 mm, confirming recent modeling efforts by Lyard and colleagues. These relatively large amplitudes evidently represent a complex interference pattern of free waves radiating from a few shallow sources, especially the Patagonian Shelf. They form approximately a standing‐wave resonance in the Gulf of Guinea.
Reversed flow events in the winter cusp ionosphere observed by the European Incoherent Scatter (EISCAT) Svalbard radar
Authors: Rinne Y. , Moen J. , Oksavik K. , Carlson H. C.
Published: October 2007

High‐resolution fast azimuth sweeps by the European Incoherent Scatter (EISCAT) Svalbard radar provide an unparalleled opportunity to study small‐scale flow disturbances in the cusp ionosphere. Observations from 11 days of the winter cusp ionosphere of high‐resolution ion flow data have been analyzed. Transient channels of reversed plasma flow appear to be a regular feature of the cusp, and they were seen in 16% of 767 analyzed EISCAT Svalbard Radar (ESR) scans. We introduce a new descriptive term, reversed flow events (RFEs), for this class of events. RFEs are defined as longitudinally elongated segments of transiently enhanced ion flow in the direction opposite to the background flow. RFEs typically occurred near the cusp inflow region in association with enhancements in the polar cap convection observed by the Super Dual Auroral Radar Network (SuperDARN). Their lifetime was found to be ∼19 min on average. Their longitudinal dimension typically exceeded the ESR field of view (>400–600 km), and ranged from ∼50 to 250 km in latitude. The occurrence rate of RFEs appears independent of the BZ and BY component polarity of the interplanetary magnetic field (IMF), and RFEs occurred for clock angles between 40° and 240°. RFE ion flow was in 95% of the cases documented to oppose the magnetic tension force, and RFEs cannot be interpreted in terms of newly opened flux. RFEs formed one by one and never simultaneously in pairs. To explain these observations, we propose an asymmetric version of the Southwood (1987) twin cell flux transfer event model to account for significant IMF BY, in which only the poleward cell located on open field lines develops.
Characteristics of steady state fluvial topography above fault‐bend folds
Authors: Miller Scott R. , Slingerland Rudy L. , Kirby Eric
Published: October 2007

In steady state convergent orogens, erosion balances lateral as well as vertical bedrock motions. For simple geometrical reasons, the difference between the total steady state erosion flux and its vertical component is up to 30% for typical fluvial slopes and bedrock streamline inclinations, suggesting that lateral advection is also likely to be expressed topographically. In order to understand these geomorphologic consequences, we focus on steady state topography developed on active fault‐bend folds. First, we derive an analytical solution for the slopes of detachment‐limited streams that incorporates lateral advection. Next, we conduct experiments using a numerical two‐dimensional landscape evolution model (Channel‐Hillslope Integrated Landscape Development model (CHILD)) incorporating linear diffusion on hillslopes and detachment‐limited stream channel incision above a fault‐bend fold. The concavity and steepness indices of steady state long profiles are functions of bedrock velocity magnitude and direction, streamflow direction, and fluvial erosivity. Asymmetry of mountain range profiles varies as a function of fluvial erosivity or bedrock velocity only if we account for the lateral velocity component. This asymmetry is equally sensitive to this lateral component, fluvial incision, and hillslope diffusion. However, the effect of diffusion on drainage divide position is significant only at high diffusivities, short length scales, low bedrock advection rates, or relatively low fluvial erosivity. Thus in most mountain ranges and fault blocks, drainage divide migration is expected to be dictated by stream channel erosion. Model results are shown to be consistent with topography in the Siwalik Hills, Nepal, which overlie fault‐bend folds produced above the frontal fault systems in the Himalayan foreland.
Targeting the cannabinoid CB2 receptor: modelling and structural determinants of CB2 selective ligands
Authors: Poso A , Huffman J W
Published: November 2007

Recent developments indicate that CB2 receptor ligands have the potential to become therapeutically important. To explore this potential, it is necessary to develop compounds with high affinity for the CB2 receptor and little affinity for the CB1 receptor. This review will discuss structure‐activity relations at both receptors for classical cannabinoids and cannabimimetic indoles. Examples of CB2 selective ligands from both classes of compounds are presented and the structural features leading to selectivity are described. Two approaches, receptor mutations and molecular modelling, have been employed to investigate the interaction of ligands with both cannabinoid receptors. These results obtained from these techniques are discussed.

British Journal of Pharmacology(2008)153, 335–346; doi:10.1038/sj.bjp.0707567; published online 5 November 2007