bluuebunny/crossref_metadata_2025 huggingface dataset:
English Musical Life—A Symposium (I-III)
Authors: Gerhard Roberto , Wellesz Egon , Seiber Matyas
Published: March 2010

“It is a blessing”—a friend once told me—“that as a rule you musicians should beinarticulate.” I need hardly add that my outspoken friend was himself a literary man. The answer, which of course did not then occur to me, might have been: “Well, what of it? if we take it that the only thing worth bothering about is theineffable,” though I doubt whether my friend could have agreed. He went on: “Look at all the nonsense your best people have uttered as soon as they generalize upon characteristics and, above all, upon the merits of their own or other nations' music. From Rousseau, if you take him to be one of you, to Debussy's Monsieur Croche Anti-dilettante, one could make a staggering anthology, and that is leaving contemporaries in peace.” True enough. Clearly, we must needs take the literary man at his word, but who would dream of taking a musician at his? The English: that unmusical nationpar excellence, is a notion still deeply rooted in Continental minds. English music since Delius leading the world in “quality and quantity” is a more recent view, propounded by no mean authority on this side of the Channel. The extremes, I suppose, compensate and cancel each other. Still, one often wishes to exclaim with Swift: “I have hated all nations, professions and communities, and all my love is for individuals.”
Opera in America
Authors: Heinsheimer H. W.
Published: March 2010

For all practical purposes opera in America was, for a long period, a mere luxury product for the few, a social event much more than an artistic undertaking. It had not played any significant part in the spiritual and cultural development of the nation. To Europeans, opera in America meant only the making of as much money as possible in the shortest possible time. To Americans it meant the display of the most precious jewels and the most expensive gowns of a few hundred privileged families at the Metropolitan Opera House in New York. And for the rest of the population it meant practically nothing.
Activity in Switzerland
Authors: Reich Willi
Published: March 2010

Nothing could better demonstrate the importance of Switzerland in the world's cultural life than the fact that this ‘isle of peace’ is the only place on the European Continent where music is fostered in a truly international sense. This cultivation springs from the old traditions of the Swiss cities, where music has always been kept alive.
Opera and ‘Peter Grimes’
Authors: Stein Erwin
Published: March 2010

The chief merit of Benjamin Britten's ‘Peter Grimes’ seems to me that it sets an example once again of what this odd, complex and very exciting form of art called opera really means. It is an odd form because the blend of realism and illusion, inherent in every theatrical production, is adulterated by the irrealistic ingredient of music; it is complex because it is a synthesis of heterogeneous kinds of arts; but it is a very exciting experience to observe music becoming an all-important element in life, even if only on the stage. It would be erroneous to believe that one can make an opera by just setting music to a play. Opera is not a drama plus music. The additional medium entirely changes the conditions and laws of the drama. It penetrates every detail of the scene and imbues with a new element the words, the acting, the decors and the entire dramatic context. Music is apt to increase both the strength and subtlety of dramatic expression by superimposing its own dynamic and flexibility on the logic of the words and the set picture of the scene. This should be borne in mind even during the conception of the libretto which must leave space for the infiltration of music.
New Soviet Chamber Music
Authors: Boelza Igor
Published: March 2010

Chamber music is a medium much favoured by Soviet composers, who have added a number of interesting works to this repertoire in recent years. Notable have been Reinhold Gliere's fourth quartet written in a classic fourmovement form, and the ninth quartet by Nikolai Myaskovsky, who, like Rachmaninov in his third symphony, places a scherzo in the middle of a slow movement.
New Music in Palestine
Authors: Gradenwitz Peter
Published: March 2010

Interest in music must be greater in Palestine than in any other country in the world, for where else do you find a community of little more than half a million (some 70–75 per cent, of Palestine's one and a half million inhabitants belong to oriental communities) having at their service a fully equipped symphony orchestra and opera company (with an orchestra of its own), and a broadcasting station with yet another symphony orchestra at its command? Orchestral and chamber music may be heard in the towns almost any day of the week, and the rural communities are not only regularly visited by artists from the three major towns—Jerusalem, Tel-Aviv, and Haifa—but have also a forty-piece orchestra of their own, meeting for a couple of concerts and for rehearsals once every month, with the members coming from all parts of the country.
News From Italy
Authors: Panain Guido
Published: March 2010

Italian musicians, both young and old, have been notably active during the war period. Until the Spring of 1943–the eve of disaster—there were many outstanding performances of theatrical and symphonic compositions.

As a result of the blackout and the increase in aerial warfare, the theatres presented their performances during the day, but the concert halls continued their activities as usual—albeit the performances were often interrupted by the sound of the air-raid siren.
Béla Bartók: An Estimate and an Appreciation
Authors: Chapman Ernest
Published: March 2010

The history of nineteenth-century Hungarian art music, like that of England, is mainly one of foreign domination. Although Liszt and his chief national contemporary Ferenc Erkel both gave musical expression to racial consciousness—the one in his employment of popular gypsy airs, the other in a series of patriotic operas—the accumulated weight of German tradition (Liszt) and Italian operatic supremacy (Erkel) was too heavy suddenly to be overthrown. The results, viewed from the standpoint of an indigenous national art, cannot be considered important.
Strauss During the War Years
Authors: Schuh Willi
Published: March 2010

When the second world war began, arrangements for the celebration of Strauss's seventy-fifth birthday had been completed despite the shadows cast by the approaching catastrophy. They culminated in performances of six Strauss operas which, given before an audience still international in character at the Munich State Opera in August 1939, testified to the endeavours of Clemens Kraus and his collaborators to produce Strauss's stage works in exemplary performances with the composer's closest collaboration as to his final intentions in respect of style. During the first years of the war it was possible to extend this plan, and in October 1942 the ninth of Strauss's operas, ‘Capriccio,’ was first performed in Munich. The outbreak of war took Strauss by surprise in Baden (Switzerland); and in the course of discussing the opera the composer revealed his deep concern at the disaster which the Hitlerrégimehad brought about, and his contention that the war would end in catastrophy for Germany.
Alan Rawsthorne and the Baroque
Authors: Mellers Wilfrid
Published: March 2010

When, during the eighteenth and nineteenth centuries, the English musical tradition gradually declined, fundamentally for social and economic reasons, one of the symptoms of decay was our failure to absorb the significant trends of contemporary musical evolution. It is for instance pertinent that although Haydn and Mozart were frequently played in London in the first half of the nineteenth century they exerted virtually no influence on our contemporary composers, who were unable to assimilate the implications of their sonata idiom. The great social-dramatic phase of instrumental evolution we simply by-passed, so that it's hardly surprising that when Holst and Vaughan Williams should have come to work towards the renaissance of our musical culture they should have returned to the great days—to Tudor polyphony and, behind that, folk-song and hence to a fundamentally vocal conception of their art. (The unique case of Elgar, whose magnificently ripe symphonics are as it were the culmination of a symphonic tradition that had never happened, we may legitimately regard as a ‘sport’ in our musical history.)
Anton Webern: The Man and his Music
Authors: Reich Willi
Published: March 2010

Non multa, sed multum. How happy I would be, could this saying be applied here!” With these words, Anton Webern dedicated the score of his Op. 9, the six Bagatelles for string quartet, to his friend Alban Berg. Each of these pieces, though lasting only a few seconds, contains a truly remarkable wealth of musical expression. But this old Latin adage may also very suitably be applied to the whole of Webern's work. The published list commences with a large composition for orchestra, the Passacaglia Op. 1 (1908), written after a long and strict study with Arnold Schönberg. It shows the twenty-five-year-old composer in complete command of all the traditional means of his art. Even this work, clearly influenced by Brahms's late style, betrays a peculiar originality, wrestling for its own means of expression in its melodic invention and its endeavour to expand tonality to the uttermost. Also the next work, a double Canon for mixed choir a cappella to words by Stefan George, strives for a certain conciliation between conventional ways of writing and the new presentation of a clearly conceived tone-world. The early tendency to marshal and arrange even the boldest and freest musical thoughts by orthodox musical form-laws (passacaglia, canon), remains characteristic also of Webern's latest compositions.
Orchestral Anarchy in London
Authors: Russell Thomas
Published: March 2010

Orchestral music in wartime was saved by a relatively small group of enthusiasts who cared more for music itself than for their own personal success. It was a hard struggle, which has been described elsewhere, and the enthusiasts were sustained only by their belief that, with the obstacles of war removed, a new, fruitful and progressive period of British musical history would open up to them. It will not be out of place to enquire to what extent these hopes have been fulfilled.
Music from the Films
Authors: Irving Ernest
Published: March 2010

Nearly all our famous composers have now seen their names blazoned across the ‘credit titles’ of what America calls ‘motionpictures.’ The plot may be moronic, the dialogue the most basic English, but the music may now scale the Olympian heights of classical austerity, or plumb the mazy depths of atonality and every other form of modern anti-romanticism. Gone are the days when studios shunned doctors of music like straphangers dodge the passenger sneezing in a tube. Counterpoint is no longer contraband, nor fugue verboten, a man may make a canon without being fired.
At the Ballet
Authors: de Zoete Beryl
Published: March 2010

Writing about ballet in a musical review I venture to choose among recently created ballets only those in which music and dance are most strikingly interwoven. I shall, therefore, by-pass Robert Helpmann's sensational monument of stagecraft, ‘Adam Zero,’ and come at once to Frederick Ashton's ‘Symphonic Variations,’ which caused another kind of sensation by its startling economy of means and overwhelming impression of beauty.
Introducing American Ballet
Authors: Hawkes Ralph
Published: March 2010

The six weeks' visit of the American Ballet Theatre to Covent Garden, commencing July 2, is a rare event for balletomanes. The Ballet Theatre has won its place during the war years as the foremost American dancing company, giving lengthy seasons at the Metropolitan Opera House in the spring and autumn, and undertaking important tours in many parts of the United States. It should not be confused with the Ballet Russe de Monte Carlo or the Russian Ballet Company, both of which have been playing in America since they were last seen in England before the war.
Optimal balancing of robot manipulators in point-to-point motion
Authors: Nikoobin A. , Moradi M.
Published: March 2010

In this paper, a new balancing approach called “optimal balancing” is presented for open-chain robot manipulators based on open-loop optimal control. In fact, an optimal trajectory planning problem is outlined in which states, controls and the values of counterweights must be determined simultaneously in order to minimize the given performance index for a predefined point-to-point task. Optimal balancing method can be propounded beside the other methods such as unbalancing, static balancing and adaptive balancing, with this superiority that the objective criterion value obtained of proposed method is very lower than the objective criterion value obtained of other methods. For this purpose, the optimal control problem is extended to the case where the performance index, the differential constraints and the prescribed final conditions contain parameters. Using the fundamental theorem of calculus of variations, the necessary conditions for optimality are derived which lead to the optimality conditions associated with the Pontryagin's minimum principle and an additional condition associated with the constant parameters. By developing the obtained optimality conditions for the two-link manipulator, a two-point boundary value problem is achieved which can be solved with bvp4c command in MATLAB®. The obtained results show that optimal balancing in comparison with the previous methods can reduce the performance index significantly. This method can be easily applied to the more complicated manipulator such as a three degrees of freedom articulated manipulator.
On certain cubic forms in seven variables
Authors: HARVEY M. P.
Published: March 2010

The main result of this paper is a proof of the expected asymptotic formula for the density of zeros of a family of cubic forms in seven variables. This is established using the Hardy–Littlewood circle method.
An equivalence between inverse sumset theorems and inverse conjectures for theU3norm
Authors: GREEN BEN , TAO TERENCE
Published: March 2010

We establish a correspondence betweeninverse sumset theorems(which can be viewed as classifications of approximate (abelian) groups) andinverse theorems for the Gowers norms(which can be viewed as classifications of approximate polynomials). In particular, we show that the inverse sumset theorems of Freĭman type are equivalent to the known inverse results for the GowersU3norms, and moreover that the conjectured polynomial strengthening of the former is also equivalent to the polynomial strengthening of the latter. We establish this equivalence in two model settings, namely that of the finite field vector spaces2n, and of the cyclic groups ℤ/Nℤ.

In both cases the argument involves clarifying the structure of certain types ofapproximate homomorphism.
Water masses’ bacterial community structure and microbial activities in the Ross Sea, Antarctica
Authors: Celussi Mauro , Bergamasco Andrea , Cataletto Bruno , Umani Serena Fonda , Del Negro Paola
Published: March 2010

During the summer 2005/06, an oceanographic cruise was carried out in the Ross Sea, from Cape Adare, through the Terra Nova Bay polynya to the eastern edge of the Ross Ice Shelf. We analysed microbial activities (prokaryotic carbon production, protease, phosphatase, beta-glucosidase and lipase activity) and bacterial community structure (using Denaturing Gradient Gel Electrophoresis - DGGE) in order to establish if differences in bacterioplankton assemblages and their metabolic requirements occur within the five Ross Sea water masses: Antarctic Surface Waters (AASW), High Salinity Shelf Water (HSSW), Ice Shelf Water (ISW), Antarctic Bottom Water (AABW), Circumpolar Deep Water (CDW). Differences in activities were found between the highly active AASW and all the other water bodies. A Principal Component Analysis highlighted two main gradients: in the Cape Adare area (AASWn, CDW and AABW) higher phosphatase, lipase and glycolytic activities, increasing towards the surface, were identified, whereas in the southern sector of the basin [AASWs and (m)HSSW] higher leucine uptake and polypeptide degradation characterized the second gradient. DGGE fingerprinting showed for the first time that different water masses harboured diverse bacterial communities, highlighting the high specificity of deep water assemblages.Alpha- andGammaproteobacteriarepresented the main phylogenetic groupings in all samples and no substantial difference in the phylogenetic composition of assemblages was found between different water masses.
Malonaldehyde formation and DNA fragmentation: two independent sperm decays linked to reactive oxygen species
Authors: Montjean Debbie , Ménézo Yves , Benkhalifa Moncef , Cohen Marc , Belloc Stephanie , Cohen-Bacrie Paul , de Mouzon Jacques
Published: March 2010

Malondialdehyde (MDA), a product involved in membrane lipid peroxidation, was dosed in the sperm of 163 patients who had consulted the clinic regarding hypofertility. We attempted to determine if there was correlation between MDA content, sperm World Health Organization parameters and DNA fragmentation that results mainly from reactive oxygen species assaults. We found that no correlation could be established; however MDA and sperm decondensation were shown to be significantly linked. The impact of membrane polyunsaturated fatty acids and the role of phospholipid hydroperoxide glutathione peroxidase are discussed.
Automatic summarisation of discussion fora
Authors: TIGELAAR ALMER S. , OP DEN AKKER RIEKS , HIEMSTRA DJOERD
Published: March 2010

Web-based discussion fora proliferate on the Internet. These fora consist of threads about specific matters. Existing forum search facilities provide an easy way for finding threads of interest. However, understanding the content of threads is not always trivial. This problem becomes more pressing as threads become longer. It frustrates users that are looking for specific information and also makes it more difficult to make valuable contributions to a discussion. We postulate that having a concise summary of a thread would greatly help forum users. But, how would we best create such summaries? In this paper, we present an automated method of summarising threads in discussion fora. Compared with summarisation of unstructured texts and spoken dialogues, the structural characteristics of threads give important advantages. We studied how to best exploit these characteristics. Messages in threads contain both explicit and implicit references to each other and are structured. Therefore, we term the threadshierarchical dialogues. Our proposed summarisation algorithm produces one summary of an hierarchical dialogue by ‘cherry-picking’ sentences out of the original messages that make up a thread. We try to select sentences usable for obtaining an overview of the discussion. Our method is built around a set of heuristics based on observations of real fora discussions. The data used for this research was in Dutch, but the developed method equally applies to other languages. We evaluated our approach using a prototype. Users judged our summariser as very useful, half of them indicating they would use it regularly or always when visiting fora.
Environment and object mental images in patients with representational neglect: Two case reports
Authors: PALERMO LIANA , NORI RAFFAELLA , PICCARDI LAURA , GIUSBERTI FIORELLA , GUARIGLIA CECILIA
Published: March 2010

The aim of this study was to shed light on the nature of the imagery deficits in two patients with representational neglect and to determine whether representational neglect is affected by the content of the mental images the patients have to generate, inspect and manipulate. In particular, we submitted two patients with different types of representational neglect to a battery of visual mental imagery tests to assess the different kinds of imagery processes. We found that Patient 1,whose performance was asymmetrical on the O’Clock Test, performed poorly on tasks involving the mental generation, inspection and manipulation of objects but showed no deficit on tasks involving the mental generation, inspection and manipulation of environments. On the other hand, Patient 2, whose performance was asymmetrical on the Familiar Squares Description Test, performed poorly on tasks involving the mental generation, inspection and manipulation of environments, but not on tasks involving the mental generation, inspection and manipulation of objects. Our results demonstrate that environments and objects in the imagery domain can be represented separately and can be selectively affected by damage following brain lesions. (JINS, 2010,16, 921–932.)
Twisted geometric Satake equivalence
Authors: Finkelberg Michael , Lysenko Sergey
Published: March 2010

Let k be an algebraically closed field and O = k[[t]] ⊂ F = k((t)). For an almost simple algebraic group G we classify central extensions 1 → $\mathbb{G}_m\to E\to G(\bm{F})\$m → E → G(F) → 1; any such extension splits canonically over G(O). Fix a positive integer N and a primitive character ζ : μN(K) →$\mathbb{Q}}_\ell^*}$ (under some assumption on the characteristic of k). Consider the category of G(O)-bi-invariant perverse sheaves on E with $\mathbb{G}_m$m-monodromy ζ. We show that this is a tensor category, which is tensor equivalent to the category of representations of a reductive group ǦE,N. We compute the root datum of ǦE,N.
Psoriasis
Authors: Navarini Alexander A. , Trüeb Ralph M.
Published: March 2010

Die Psoriasis ist eine Hautkrankheit, die sich nach außen hin durch scharf begrenzte, gerötete Plaques infolge entzündlicher Hautinfiltration und einer fest haftenden, silbrig weißen Schuppung infolge epidermaler Hyperproliferation und Parakeratose auszeichnet. Der Name leitet sich von πσόρα, Krätze, ab, und die Erkrankung wurde im Altertum mit Aussatz gleichgesetzt, was die Bedeutung vom Juckreiz bzw. die soziale Stigmatisierung unterstreicht. Heute wird die Psoriasis als primäre, autoimmun und genetisch bedingte, T-Zell-vermittelte Systemkrankheit mit entzündlichen Manifestationen an Haut, Nägeln und Gelenken (Psoriasis Arthritis) sowie einer Reihe von Ko-Morbiditäten aufgefasst. Dementsprechend sind die therapeutischen Ansätze antientzündlich, proliferationshemmend und keratolytisch bzw. richten sich nach dem Schweregrad der Erkrankung, bezogen auf die Flächenausdehnung und Einzeleffloreszenz (PASI), Beeinträchtigung der Lebensqualität (DLQI) und besondere Lokalisationen (Psoriasis inversa, Palmoplantarpsoriasis, Nagelpsoriasis), sowie Patientenalter und Ko-Morbiditäten (Arthritis, metabolisches Syndrom, kardiovaskuläre Erkrankungen, Depression, Suizidalität). In 80 % liegt eine leichte Psoriasis vor, die mittels äußerlicher (Kortikosteroide, Vit. D-Analoga) und Phototherapie (PUVA, nbUVB) hinreichend behandelt werden kann, 20 % benötigen aufgrund der Ausdehnung bzw. Schwere der Erkrankung eine systemische Therapie (Acitretin, Methotrexat, Ciclosporin) oder Therapie mittels der neuen Substanzklasse der Biologics. Vor allem bei den schweren Formen der Psoriasis sind der psychischer Leidensdruck, die Ko-Morbiditäten und medizinökonomische Überlegungen im individuellen Behandlungsplan mit zu berücksichtigen.
Urtikaria – die häufigste dermatologische Erkrankung
Authors: Ballmer-Weber Barbara K. , Kündig Thomas M.
Published: March 2010

Die Urtikaria ist ein sehr häufiges Krankheitsbild, welches 15 – 25 % der Bevölkerung mindestens einmal im Leben betrifft. Dieser Artikel fasst die wichtigsten klinischen Merkmale sowie Kriterien zur Einteilung der Urtikaria zusammen. Bedeutsam ist insbesondere die Suche nach Auslösern und Triggerfaktoren, damit diese gemieden werden können. Diagnostische und therapeutische Algorithmen, welche sich an die neuesten Empfehlungen der Europäischen Gesellschaft für Allergologie und Klinische Immunologie (EAACI), das Europäische Dermatologische Forum (EDF), und die World Allergy Organization (WAO) anlehnt, werden vorgestellt und diskutiert.
Sexuell übertragbare Infektionen, STI
Authors: Theler Barbara , Läuchli Severin
Published: March 2010

Sexuell übertragbare Infektionen mit den Hauptmanifestationsformen der Urethritis, des genitalen Ulcus und der Genitalwarzen bedürfen einer konsequenten Diagnostik und Therapie, um ihre Verbreitung einzuschränken. Urethritiden sind am häufigsten durch Gonokokken und Chlamydien ausgelöst, wobei letztere auch paucisymptomatisch verlaufen können. Der Erregernachweis soll stets angestrebt werden mittels Direktpräparat und Kultur bzw. PCR, die gezielte antibiotische Behandlung ist in der Regel problemlos. Das Genitalulcus hat eine breite Differentialdiagnose von infektiösen und nicht-infektiösen Ursachen, am häufigsten ist die Herpes simplex Infektion. Es ist bedeutend, da es die Transmission von HIV begünstigen kann. Die Syphilis verläuft stadienhaft; während die Diagnose im Initialstadium manchmal schwierig ist, sind im weiteren Verlauf die serologischen Teste wegweisend. Genitalwarzen als Ausdruck einer HPV-Infektion können meistens einfach klinisch diagnostiziert werden. Insbesondere bei gewissen hochrisiko-Typen von HPV und bei Immunsuppression kommt eine maligne Entartung der Läsionen vor. Nebst verschiedenen destruierenden Therapieverfahren bestehen auch wirksame durch den Patienten selber lokal anzuwendende Therapien.
Phlebologie und Wundbehandlung
Authors: Hafner Jürg , Läuchli Severin , French Lars E.
Published: March 2010

Venenkrankheiten sind in der Bevölkerung weit verbreitet und chronische Wunden verursachen hohe Morbidität und Kosten. Die Prävalenz der schweren Formen der chronischen venösen Insuffizienz ist rückläufig, einerseits dank der verbesserten Thrombosediagnostik und -therapie und andererseits dank der verbesserten Chirurgie der Varikosis und deren Folgen. Das Spektrum der chronischen Wunden hat sich vom venösen Ulkus in Richtung komplexer Pathologien verschoben, aber gleichzeitig haben auch die Behandlungsmöglichkeiten zugenommen. Die moderne Phlebologie kann die Varikose wirksam behandeln, die Spätschäden von Varikosis und tiefer Venenthrombose verhindern und der großen Mehrzahl von Patienten mit chronischen Wunden weiterhelfen.
Phytoplankton photocompensation from space‐based fluorescence measurements
Authors: Morrison J. Ruairidh , Goodwin Deborah S.
Published: March 2010

Recent satellite‐derived observations linked global scale phytoplankton fluorescence variability with iron stress and hinted at photophysiological responses associated with changing light levels. These photocompensation reactions, the sum of photoacclimation and photoadaptation, were examined with climatological data for the Gulf of Maine. Significant seasonal variability was observed in the fluorescence quantum yield that was unrelated to patterns of biomass. Up to 89% of the variability in the fluorescence quantum yield was explained by a physiology‐based photocompensation model. Spatial variability in seasonal patterns was associated with differing hydrodynamic regimes. This variability in the quantum yield demonstrates that satellite‐based fluorescence is inappropriate for phytoplankton biomass determinations. More importantly, the work presented here provides the modeling foundation for fluorescence‐based investigations of temporal and spatial variability in phytoplankton physiology associated with growth irradiance. These space‐based physiological observations have the potential to decrease uncertainties in future ocean color derived primary productivity estimates.
Earth's dynamo limit of predictability
Authors: Hulot G. , Lhuillier F. , Aubert J.
Published: March 2010

Earth's magnetic field is currently decreasing, reducing the protection it offers against charged particles coming from space and increasing space weather hazards within the near‐Earth environment. Modeling the future evolution of the field is thus of considerable interest. But how far in the future this can conceivably be done is still an open question. Here we report on the first systematic investigation of the limit of predictability of fully consistent 3D numerical dynamo simulations, and suggest that the Earth's dynamo is likely unpredictable beyond a century, making decade timescale forecasts of the main magnetic field conceivable, but rendering longer‐term predictions, such as the timing of the next reversal, totally unpredictable.
Can in situ floats and satellite altimeters detect long‐term changes in Atlantic Ocean overturning?
Authors: Willis Josh K.
Published: March 2010

Global warming has been predicted to slow the Atlantic Meridional Overturning Circulation (AMOC), resulting in significant regional climate impacts across the North Atlantic and beyond. Here, satellite observations of sea surface height (SSH) along with temperature, salinity and velocity from profiling floats are used to estimate changes in the northward‐flowing, upper limb of the AMOC at latitudes around 41°N. The 2004 through 2006 mean overturning is found to be 15.5 ± 2.4 Sv (106 m3/s) with somewhat smaller seasonal and interannual variability than at lower latitudes. There is no significant trend in overturning strength between 2002 and 2009. Altimeter data, however, suggest an increase of 2.6 Sv since 1993, consistent with North Atlantic warming during this same period. Despite significant seasonal to interannual fluctuations, these observations demonstrate that substantial slowing of the AMOC did not occur during the past 7 years and is unlikely to have occurred in the past 2 decades.
Geologic setting of serpentine deposits on Mars
Authors: Ehlmann B. L. , Mustard J. F. , Murchie S. L.
Published: March 2010

Serpentine, recently discovered on Mars using Mars Reconnaissance Orbiter data, is uncommon but found in three geologic settings: (1) in mélange terrains at the Claritas Rise and the Nili Fossae, (2) associated with a few southern highlands impact craters, and (3) associated with a regional olivine‐rich stratigraphic unit near the Isidis basin. Any presently active serpentinization processes would be occurring beneath the surface and mineral products would not be apparent with surface and orbital data; however, finding serpentine in several Noachian terrains indicates active serpentinization processes in Mars' past. Important implications are the past production of magnetite, which may contribute to chemical remnant magnetization of Mars' crust, and production of H2, which is a suitable energy source for chemosynthetic microbial life.
Reorganization of Gap Junctions after Focused Ultrasound Blood–Brain Barrier Opening in the Rat Brain
Authors: Alonso Angelika , Reinz Eileen , Jenne Jürgen W , Fatar Marc , Schmidt-Glenewinkel Hannah , Hennerici Michael G , Meairs Stephen
Published: March 2010

Ultrasound-induced opening of the blood–brain barrier (BBB) is an emerging technique for targeted drug delivery to the central nervous system. Gap junctions allow transfer of information between adjacent cells and are responsible for tissue homeostasis. We examined the effect of ultrasound-induced BBB opening on the structure of gap junctions in cortical neurons, expressing Connexin 36, and astrocytes, expressing Connexin 43, after focused 1-MHz ultrasound exposure at 1.25 MPa of one hemisphere together with intravenous microbubble (Optison, Oslo, Norway) application. Quantification of immunofluorescence signals revealed that, compared with noninsonicated hemispheres, small-sized Connexin 43 and 36 gap-junctional plaques were markedly reduced in areas with BBB breakdown after 3 to 6 hours (34.02±6.04% versus 66.49±2.16%, P=0.02 for Connexin 43; 33.80±1.24% versus 36.77±3.43%, P=0.07 for Connexin 36). Complementing this finding, we found significant increases in large-sized gap-junctional plaques (5.76±0.96% versus 1.02±0.84%, P=0.05 for Connexin 43; 5.62±0.22% versus 4.65±0.80%, P=0.02 for Connexin 36). This effect was reversible at 24 hours after ultrasound exposure. Western blot analyses did not show any change in the total connexin amount. These results indicate that ultrasound-induced BBB opening leads to a reorganization of gap-junctional plaques in both neurons and astrocytes. The plaque-size increase may be a cellular response to imbalances in extracellular homeostasis after BBB leakage.
Decomposing CO2 emissions data into a pair of logistic growth pulses
Authors: Alexandrov Gleb
Published: March 2010

Numerous scenarios of emissions growth presume that it can not grow infinitely: there are certain limits that may not or must not be exceeded. Applying the theory of pulsing logistic growth, I detected two pulses of logistic growth. This led me to the conclusion that constructing a scenario of emissions growth one should pay attention to the fact that limits to their growth do not remain constant.
Barrett's metaplasia: molecular mechanisms and nutritional influences
Authors: Slack Jonathan M.W. , Colleypriest Benjamin J. , Quinlan Jonathan M. , Yu Wei-Yuan , Farrant Mark J. , Tosh David
Published: March 2010

Barrett's metaplasia is discussed in the context of a general theory for the formation of metaplasias based on developmental biology. The phenotype of a particular tissue type becomes established during embryonic development by the expression of a specific set of transcription factors. If this combination becomes altered, then the tissue type can be altered. Such events may occur by mutation or by environmental effects on gene expression, normally within the stem cell population of the tissue. A macroscopic patch of metaplastic tissue will arise only if the new gene activity state is self-sustaining in the absence of its original causes, and if the new tissue type can outgrow the parent tissue type. An important candidate gene for the causation of Barrett's metaplasia is Cdx2 (Caudal-type homeobox 2). In normal development, this is expressed in the future intestine, but not the future foregut. Mouse knockout studies have shown that it is needed for intestinal development, and that its loss from adult intestine can lead to squamous transformations. It is also expressed in Barrett's metaplasia and can be activated in oesophageal cell cultures by treatment with bile acids. We have investigated the ability of Cdx2 to bring about intestinal transformations in oesophageal epithelium. Our results show that Cdx2 can activate a programme of intestinal gene expression when overexpressed in HET-1A cells, or in fetal epithelium, but not in the adult epithelium. This suggests that Cdx2, although necessary for formation of intestinal tissue, is not sufficient to provoke Barrett's metaplasia in adult life and that overexpression of additional transcription factors is necessary. In terms of diet and nutrition, there is a known association of Barrett's metaplasia with obesity. This may work through an increased risk of gastro-oesophageal reflux. Acid and bile are known to activate Cdx2 expression in oesophageal cells. It may also increase circulating levels of TNFα (tumour necrosis factor α), which activates Cdx2. In addition, there may be effects of diet on the composition of the bile.
Role of the micro-environment in Barrett's carcinogenesis
Authors: Lao-Sirieix Pierre , Fitzgerald Rebecca C.
Published: March 2010

Most epithelial cancers occur on the background of chronic exposure to damaging agents which is reflected in the long lag phase from development of a pre-invasive lesion to the development of a carcinoma. Luminal refluxate has long been recognized to be associated with Barrett's oesophagus, although causal mechanisms have not been clearly defined. Recently, obesity and dietary nitric oxide have also been implicated in the disease pathogenesis. We have demonstrated that acid can alter cell kinetics and, together with nitric oxide, can induce double-stranded DNA breaks. Aside from exposure to luminal factors, the stromal micro-environment may also be important. There is increasing evidence to suggest that inflammatory pathways such as TGF (transforming growth factor) β may play a role in Barrett's oesophagus carcinogenesis. Hence stromal–epithelial–luminal interactions may influence cell behaviour. As sequelae to this, it is possible that the niches created by the micro-environment may influence genetic epithelial diversity observed within the Barrett's oesophagus segment.
Biomarkers in Barrett's oesophagus
Authors: Huang Qizhi , Hardie Laura J.
Published: March 2010

Biomarkers are needed to screen multiple stages in the clinical pathway of Barrett's oesophagus patients; from disease diagnosis to risk stratification and predicting response to therapy. Routes to the identification of biomarkers have been recognized by known molecular features of the disease and more recently through transcriptomic, methylation and proteomic screening approaches. The majority of Barrett's oesophagus patients remain undiagnosed in the general population. In order to develop a tool to screen for Barrett's oesophagus in the primary care setting, minimally invasive sampling methods coupled with immunocytology-based biomarkers are currently being assessed. Biomarkers may also have utility in surveillance programmes by allowing endoscopic interval to be adjusted according to individual neoplastic risk. Many individual biomarkers have been proposed in this regard, but have frequently been assessed in studies of limited power, or have lacked sufficient sensitivity or specificity when assessed in wider population-based studies. Biomarker panels may provide a route forward. In this regard, a panel of methylation markers has shown promise in a multicentre, double-blind, validation study. Biomarkers are also being developed to improve detection of high-grade dysplasia and oesophageal adenocarcinoma, utilizing brush cytology combined with FISH (fluorescence in situ hybridization), and to assess therapeutic success and risk of complication during photodynamic therapy. Finally, we outline progress in identifying alternative sources of biomarkers for this condition.
The role of Cdx genes in the gut and in axial development
Authors: Beck Felix , Stringer Emma J.
Published: March 2010

The Cdx (Caudal-type homeobox) group of ParaHox genes (Cdx1, Cdx2 and Cdx4 in the mouse) perform multiple functions in mammalian development. Cdx1 is concerned with axial positional information, and its deletion appears to have no important effect other than a disturbance of axial patterning. In contrast, Cdx2 is required for trophoblast differentiation, axial patterning and extension, as well as for morphological specification (i.e. patterning) of gut endoderm. Cdx4-knockout animals do not present an abnormal phenotype, but, when combined with Cdx2 haploinsufficiency, present a dramatic picture involving abnormal cloacal specification. The latter is probably due in large part to defective paraxial mesodermal development in the caudal region, but may also involve defective endodermal growth. A significant degree of redundancy is apparent between the Cdx genes with respect to caudal extension and possibly also during gut development.
Pathophysiology of intestinal metaplasia of the stomach: emphasis on CDX2 regulation
Authors: Barros Rita , Camilo Vânia , Pereira Bruno , Freund Jean-Noel , David Leonor , Almeida Raquel
Published: March 2010

IM (intestinal metaplasia) of the stomach is a pre-neoplastic lesion that usually follows Helicobacter pylori infection and that confers increased risk for gastric cancer development. After setting the role played by CDX2 (Caudal-type homeobox 2) in the establishment of gastric IM, it became of foremost importance to unravel the regulatory mechanisms behind its de novo expression in the stomach. In the present paper, we review the basic pathology of gastric IM as well as the current knowledge on molecular pathways involved in CDX2 regulation in the gastric context.
The role of Cdx2 in Barrett's metaplasia
Authors: Colleypriest Benjamin J. , Farrant J. Mark , Slack Jonathan M.W. , Tosh David
Published: March 2010

Metaplasia (or transdifferentiation) is defined as the transformation of one tissue type to another. Clues to the molecular mechanisms that control the development of metaplasia are implied from knowledge of the transcription factors that specify tissue identity during normal embryonic development. Barrett's metaplasia describes the development of a columnar/intestinal phenotype in the squamous oesophageal epithelium and is the major risk factor for oesophageal adenocarcinoma. This particular type of cancer has a rapidly rising incidence and a dismal prognosis. The homoeotic transcription factor Cdx2 (Caudal-type homeobox 2) has been implicated as a master switch gene for intestine and therefore for Barrett's metaplasia. Normally, Cdx2 expression is restricted to the epithelium of the small and large intestine. Loss of Cdx2 function, or conditional deletion in the intestine, results in replacement of intestinal cells with a stratified squamous phenotype. In addition, Cdx2 is sufficient to provoke intestinal metaplasia in the stomach. In the present paper, we review the evidence for the role of Cdx2 in the development of Barrett's metaplasia.
Cellular origin of Barrett's metaplasia and oesophageal stem cells
Authors: Barbera Mariagnese , Fitzgerald Rebecca C.
Published: March 2010

Barrett's oesophagus is a metaplastic pre-malignant disorder and the only established precursor lesion for oesophageal adenocarcinoma. Barrett's oesophagus develops when the normal stratified squamous epithelium of the lower oesophagus is replaced by a columnar lined mucosa with intestinal differentiation, usually in the context of chronic gastro-oesophageal reflux disease. The cellular and molecular mechanisms by which this metaplastic transformation occurs are poorly understood. Abnormal differentiation of multipotent stem cells in the squamous oesophagus, triggered by exposure to refluxate, is one potential mechanism. These stem cells could be located in the basal layer of the squamous oesophageal epithelium and/or in the neck region of the oesophageal submucosal gland ducts; however, their exact location and identification are still matter of discussion. Three-dimensional models combined with state-of-the-art imaging techniques are now applied to characterize the squamous epithelium in human oesophageal samples, and this could unveil essential information to identify these progenitor cells. Locating stem cells in human squamous oesophagus could have important implications for our understanding of Barrett's oesophagus and remarkably improve our future strategies for its prevention.
Machines on Genes: Enzymes that Make, Break and Move DNA and RNA
Authors: Stark W. Marshall , Luisi Ben F. , Bowater Richard P.
Published: March 2010

As the vital information repositories of the cell, the nucleic acids DNA and RNA pose many challenges as enzyme substrates. To produce, maintain and repair DNA and RNA, and to extract the genetic information that they encode, a battery of remarkable enzymes has evolved, which includes translocases, polymerases/replicases, helicases, nucleases, topoisomerases, transposases, recombinases, repair enzymes and ribosomes. An understanding of how these enzymes function is essential if we are to have a clear view of the molecular biology of the cell and aspire to manipulate genomes and gene expression to our advantage. To bring together scientists working in this fast-developing field, the Biochemical Society held a Focused Meeting, ‘Machines on Genes: Enzymes that Make, Break and Move DNA and RNA’, at Robinson College, University of Cambridge, U.K., in August 2009. The present article summarizes the research presented at this meeting and the reviews associated with the talks which are published in this issue of Biochemical Society Transactions.
The Escherichia coli DNA translocase FtsK
Authors: Sherratt David J. , Arciszewska Lidia K. , Crozat Estelle , Graham James E. , Grainge Ian
Published: March 2010

Escherichia coli FtsK is a septum-located DNA translocase that co-ordinates the late stages of cytokinesis and chromosome segregation. Relatives of FtsK are present in most bacteria; in Bacillus subtilis, the FtsK orthologue, SpoIIIE, transfers the majority of a chromosome into the forespore during sporulation. DNA translocase activity is contained within a ~ 512-amino-acid C-terminal domain, which is divided into three subdomains: α, β and γ. α and β comprise the translocation motor, and γ is a regulatory domain that interacts with DNA and with the XerD recombinase. In vitro rates of translocation of ~ 5 kb·s−1 have been measured for both FtsK and SpoIIIE, whereas, in vivo, SpoIIIE has a comparable rate of translocation. Translocation by both of these proteins is not only rapid, but also directed by DNA sequence. This directionality requires interaction of the γ subdomain with specific 8 bp DNA asymmetric sequences that are oriented co-directionally with replication direction of the bacterial chromosome. The γ subdomain also interacts with the XerCD site-specific recombinase to activate chromosome unlinking by recombination at the chromosomal dif site. In the present paper, the properties in vivo and in vitro of FtsK and its relatives are discussed in relation to the biological functions of these remarkable enzymes.
Catalysis of site-specific recombination by Tn3 resolvase
Authors: Olorunniji Femi J. , Stark W. Marshall
Published: March 2010

The active-site interactions involved in the catalysis of DNA site-specific recombination by the serine recombinases are still incompletely understood. Recent crystal structures of synaptic γδ resolvase–DNA intermediates and biochemical analysis of Tn3 resolvase mutants have provided new insights into the structure of the resolvase active site, and how interactions of the catalytic residues with the DNA substrate might promote the phosphoryl transfer reactions.
Substrate recognition and catalysis by flap endonucleases and related enzymes
Authors: Tomlinson Christopher G. , Atack John M. , Chapados Brian , Tainer John A. , Grasby Jane A.
Published: March 2010

FENs (flap endonucleases) and related FEN-like enzymes [EXO-1 (exonuclease-1), GEN-1 (gap endonuclease 1) and XPG (xeroderma pigmentosum complementation group G)] are a family of bivalent-metal-ion-dependent nucleases that catalyse structure-specific hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair and recombination. In the case of FENs, the ability to catalyse reactions on a variety of substrates has been rationalized as a result of combined functional and structural studies. Analyses of FENs also exemplify controversies regarding the two-metal-ion mechanism. However, kinetic studies of T5FEN (bacteriophage T5 FEN) reveal that a two-metal-ion-like mechanism for chemical catalysis is plausible. Consideration of the metallobiochemistry and the positioning of substrate in metal-free structures has led to the proposal that the duplex termini of substrates are unpaired in the catalytically active form and that FENs and related enzymes may recognize breathing duplex termini within more complex structures. An outstanding issue in FEN catalysis is the role played by the intermediate (I) domain arch or clamp. It has been proposed that FENs thread the 5′-portion of their substrates through this arch, which is wide enough to accommodate single-stranded, but not double-stranded, DNA. However, FENs exhibit gap endonuclease activity acting upon substrates that have a region of 5′-duplex. Moreover, the action of other FEN family members such as GEN-1, proposed to target Holliday junctions without termini, appears incompatible with a threading mechanism. An alterative is that the I domain is used as a clamp. A future challenge is to clarify the role of this domain in FENs and related enzymes.