bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibition of lactate dehydrogenase ex rabbit muscle by Cibacron Blue 3G-A bound to water-soluble hydroxyethylcellulose
Authors: Mislovičová Danica , Gemeiner Peter , Šoltés Ladislav
Published: September 2010

The interaction between lactate dehydrogenase and hydroxyethylcellulose - Cibacron Blue 3G-A conjugates was investigated kinetically. These conjugates were obtained by covalent binding of Cibacron Blue to water-soluble hydroxyethylcelluloses, of average relative molecular masses 2.5 . 104 to 11.6 . 104. The polymeric matrix (non-branched β-glucan) was, unlike the branched α-glucans, found to inhibit the action of the dye, irrespective of the molecular mass of this matrix. With increasing amount of the bound dye the interaction between the dye and the enzyme was enhanced.
Oscillations of bromine in Belousov-Zhabotinskii type reaction with oxalic acid
Authors: Ševčík Peter , Dubovská Jana
Published: September 2010

The authors studied the influence of the concentrations of reactants and catalysts on the parameters of the catalysed oscillation reaction of bromate ions with oxalic acid in the medium of sulphuric acid. Ce(IV) and Mn(III) ions induce the reaction of bromine in the oxidation state either +1 or 0 with oxalic acid. In the presence of bromate ions, the induced reaction can lead to the formation of the same quantity of bromine as in the first oscillation cycle of the oscillation reaction.
Liquidus temperatures of some systems salt-dimethyl sulphoxide and solvate formation. Preferential solvation by dimethyl sulphoxide
Authors: Pacák Petr , Sláma Ivo
Published: September 2010

Liquidus temperatures were measured for concentrated solutions of LiCl, CaCl2, ZnCl2, Zn(NO3)2, NaNO3 and Mg(NO3)2 in dimethyl sulphoxide. Crystalline solvates of salts with dimethyl sulphoxide which separated from these solutions were isolated and subjected to chemical and infrared spectroscopic analyses. It has been proved that in concentrated solutions in the mixed solvent water-dimethyl sulphoxide, the salts are preferentially solvated by dimethyl sulphoxide.
Phosphonylmethyl analogues of ribonucleoside 2',3'-cyclic phosphates and 2'(3')-nucleotide methyl esters: Synthesis and properties
Authors: Rosenberg Ivan , Holý Antonín
Published: September 2010

2'(3')-O-Phosphonylmethylribonucleosides II, III were prepared by intramolecular cyclisation of ribonucleoside 2'(3')-chloromethanephosphonates I in alkali. Treatment of the phosphonylmethyl derivatives with dicyclohexylcarbodiimide afforded cyclic six-membered esters VI, VII which are stable in acid and easily hydrolyze in alkali. Ribonucleases A, T1, T2, U2 and spleen cPDase do not split the cyclic phosphonate ester linkage of these analogues of ribonucleoside 2',3'-cyclic phosphonates.
Synthesis of 3β,4β-cyclopropano-19-nor-A-homosteroids
Authors: Joska Jiří , Fajkoš Jan , Zajíček Jaroslav
Published: September 2010

Acetolysis of the tosylate XIII, afforded the olefin XIV as the sole product. Epoxidation of the double bond gave the epoxide XV which on metal hydride reduction yielded the alcohol XVI. The structures of these products were established by spectral and chemical means and conformation of the A-homo ring in the epoxide XV is discussed on the basis of the 1H NMR spectra.
Synthesis of oligodeoxyribonucleotides using in situ prepared nucleoside methyl phosphochloridite intermediates
Authors: Smrt Jiří , Večerková Hana , Forstová Jitka , Hostomský Zdeněk , Rosenthal André
Published: September 2010

Synthesis of oligodeoxyribonucleotides on silica gel support using 5'-O-dimethoxytrityl-(N-acyl)-deoxyribonucleoside 3'-(O-methyl phosphochloridite) intermediates (I) is described. Solutions of these intermediates were prepared before use by mixing of 100 μmol l-1 solution of methyl phosphodichloridite in 1,2-dichloroethane with the same volume of 120 μmol l-1 solution of 5'-O-dimethoxytrityl-(N-acyl)-deoxyribonucleoside in 1,2-dichloroethane containing 1 mol l-1 of sym-collidine. A bench type synthesizer for this methodology is described.
Slip effects in oscillatory flow of viscoelastic liquids
Authors: Wein Ondřej
Published: September 2010

Theory has been submitted of measurement of complex viscosity, accounting, appart from the inertia of liquid, and compliance of the instrument measuring the oscillatory shear stress, also for the effect of the slip of liquid on the wall of the measuring cell.
A study of reaction of aromatic polynitro compounds with tributylstannyl hydride
Authors: Macháček Vladimír , Lyčka Antonín , Nádvorník Milan
Published: September 2010

1H, 13C, 15N, and 119Sn NMR spectra have been used to study composition and structure of reaction products from 1,3,5-trinitrobenzene, methyl 2,4,6-trinitrobenzoate, 1-dimethylamino-2,4,6-trinitrobenzene, 1-methoxy-2,4,6-trinitrobenzene, 1-chloro-2,4,6-trinitrobenzene, 2,4,6-trinitrotoluene, 3,5-dinitrobenzonitrile and methyl 3,5-dinitrobenzoate with tributylstannyl hydride in the presence of tetramethylammonium bromide.
7-O-Alkenyl and alkynyl derivatives of daunomycinone
Authors: Přikrylová Věra , Sedmera Petr , Jizba Josef V. , Vokoun Jindřich , Lipavská Helena , Podojil Miloslav , Vaněk Zdenko
Published: September 2010

Reaction of daunomycinone (I) with unsaturated alcohols and p-toluenesulfonic acid produces a mixture of 7(S)-O- and 7(R)-O-alkenyl or alkynyl derivatives II, III, VI-XVII. With daunomycinone and 2-methyl-2-propen-1-ol, the ketals IV and V are formed.
Photochemical chlorotrifluoroethylation of 1,2-, 1,3-, and 1,4-diols
Authors: Dědek Václav , Hemer Ivan
Published: September 2010

The UV light-initiated reaction of chlorotrifluoroethylene with 1,2-ethanediol (I) proceeds only in the presence of acetone and affords 2-(2-chloro-1,1,2-trifluoroethyl)-2-methyl-1,3-dioxolane (VI). It has been proved that I is first photolyzed to acetaldehyde. Its acetalization in the reaction mixture gives 2-methyl-1,3-dioxolane (V) which then undergoes chlorotrifluoroethylation. The chlorotrifluoro derivative of 1,2-ethanediol XII was prepared by hydrolysis of 4-(2-chloro-1,1,2-trifluoroethyl)-2,2-dimethyl-1,3-dioxolane (XIII). 1,3-Propanediol (II) reacted to give 5-chloro-4,4,5-trifluoro-1,3-pentanediol (XVI). Analogous reaction of 1,4-butanediol (III) and 1,3-butanediol (IV) afforded, in addition to derivatives with chlorotrifluoroethyl group at the hydroxyl-bearing carbon atom (XVII from III, XIX and XX from IV), also the respective bis-chlorotrifluoroethyl derivatives XVIII and XXI as products arising by the 1,5- or 1,6-transfer in the radical intermediates.
Synthesis and conformation of sequential basic polypeptides with branched and linear side chains
Authors: Štokrová Štěpánka , Pospíšek Jan , Šponar Jaroslav , Bláha Karel
Published: September 2010

Polypeptides (Lys-X-Ala)n and (Lys-X-Gly)n in which X represents residues of isoleucine and norleucine, respectively, and polypeptide (Tle-Lys-Ala)n, were synthesized via polymerization of 1-hydroxysuccinimidyl esters of the appropriate tripeptides to complete previously studied series. Circular dichroism (CD) spectra of the respective polymers were measured as a function of pH and salt concentration of the medium. The results were correlated with those obtained previously with the same series containing different amino acid residues at the X-position. The helix forming ability of the polypeptides (Lys-X-Ala)n with linear X side chain was found to be independent of the length. In the series (Lys-X-Gly)n the unordered conformation was the most probable one except (Lys-Ile-Gly)n. This polymer assumed the β conformation even in low salt solution at neutral pH. An agreement with some theoretical work concerned with the restriction of conformational freedom of amino acid residue branching at Cβ atom with our experimental results is evident.
Ischaemic heart disease assessment by cardiovascular magnetic resonance imaging
Authors: Raj Vimal , Agrawal S K
Published: September 2010

Ischaemic heart disease (IHD) related mortality has been on the decline, although its prevalence has been on the rise since the late 1970s. One of the contributing factors to this decline has been improved diagnosis and therapeutic management. Every clinician seeks to answer four key questions while evaluating patients with suspected or known IHD: What is the global ventricular function? What is the regional ventricular function? Is the myocardium viable? What is the status of the coronary arteries? In the past decade cardiovascular magnetic resonance (CMR) imaging has emerged as an important clinical technique with the potential of answering all the pertinent questions in a single study. This has led to a significant increase in demand and utilisation of this modality. However, many clinicians are not well versed with this technology, its clinical utility, limitations and future prospects. With the increasing prevalence of IHD, CMR imaging is likely to be used more often in its diagnosis, prognostication and management. The review describes the basic principles and practical aspects of CMR imaging, and then discusses in detail the role of CMR in the diagnosis and management of IHD, its complications, and its utility in patients with acute myocardial infarction.
Republished paper: Arterial stiffness in chronic kidney disease: causes and consequences
Authors: Chue Colin D , Townend Jonathan N , Steeds Richard P , Ferro Charles J
Published: September 2010

Chronic kidney disease is associated with elevated cardiovascular risk, and heart failure and arrhythmias are the biggest causes of cardiovascular death in this population. Increased arterial stiffness is a hallmark of chronic kidney disease and is associated with adverse alterations in cardiac structure and function that may predispose to an increased risk of cardiovascular death. These changes are already apparent in early kidney disease, which is highly prevalent in the developed world. The mechanisms underlying increased arterial stiffness in chronic kidney disease are undoubtedly complex, but an understanding is paramount to enable the development of novel therapeutic strategies to prevent or reverse this pathophysiology and therefore reduce the cardiovascular disease burden in this high-risk cohort.
Exposed Crown Surface Area: A Mathematical Index of Individual Tree Growth Potential
Authors: Hatch Charles R. , Gerrard Douglas J. , Tappeiner II John C.
Published: September 2010

A mathematical index representing relative growth potential of an individual tree is developed as a function of crown-surface area exposed to sunlight and distance from the crown to d.b.h. The index measures the relative competitiveness of an individual tree rather than the relative competitive pressure being exerted on an individual tree by surrounding trees. It effectively accounted for variation in 5-year d.b.h. growth of an even-aged pine stand.
Absorption of Water and 32P through Suberized and Unsuberized Roots of Loblolly Pine
Authors: Chung Hsu-Ho , Kramer Paul J.
Published: September 2010

Measurements were made of the rate of intake of water and 32P through suberized and unsuberized roots and root segments from seedlings of Pinustaeda L. under a pressure gradient of 31 cm Hg (41 kPa), produced by use of a vacuum pump. Water and 32P intake through suberized root segments from seedlings in storage was only 11% of the intake through unsuberized segments from roots grown in nutrient solution. Water intake through entirely suberized root systems grown in nutrient solution was about 71% and 32P uptake about 58% of those through root systems grown in nutrient solution but with 40–50% of their surface unsuberized. Uptake of water and 32P through root segments and root systems grown in vermiculite was intermediate between that for seedlings grown in nutrient solution and that for dormant root systems. Removal of all unsuberized root surface reduced the total root surface by 42%, water uptake by 54%, and 32P uptake by 70% per seedling. These results indicate that absorption of water and mineral nutrients through suberized roots may play an important role in the water economy and mineral nutrition of woody plants.
Effets à moyen terme de la fertilisation par urée ou par potassium sur Pinusbanksiana L. et le comportement de ses insectes dévastateurs: tel que Neodiprionswainei (Hymenoptera, Tenthredinidae) et Toumeyellanumismaticum (Homoptera, Coccidae)
Authors: Smirnoff W. A. , Valéro J.
Published: September 2010

The effect of fertilization on the physiology of jack pine (Pinusbanksiana Lamb.) in a natural stand and on two important foliage pests, Neodiprionswainei Middleton and Toumeyellanumismaticum Pettit and McDaniel, was studied.It was established in 1973 that fertilization with 400 kg of urea per hectare (1 ha = 1 × 104 m2) in 1969 and in 1970 was still influencing the level of chloride, the osmotic pressure and the activity of two enzymes, glutamic–oxaloacetic transaminase (GOT) and glutamic dehydrogenase (GLDH) contained in the foliage. In June 1974 in current and previous years' growth, the amount of chloride had decreased, respectively, to 81 and 50 p.p.m. (mg/kg) in fertilized trees, and the osmotic pressure increased by 37 and 49 m[Formula: see text]smol/kg. The activity of GOT and GLDH in the foliage of fertilized trees was 41 and 14 mU/g, respectively, compared with 163 and 21 mU/g, respectively, in the foliage of unfertilized trees.It was found 3 years after fertilization that the mortality of N. swainei larvae was 50% higher and the damage they caused was 42% less in fertilized trees. Also, it was observed that urea fertilization, even at low dosage, favoured T. numismaticum, this infestation increasing 2,7 and 9 times in plots fertilized with 100, 200 and 400 kg of urea nitrogen per hectare.The studies revealed, however, that fertilization with potassium may reduce T. numismaticum. The infestation in the fertilized plot showed a reduction from 42 to 21%, and in the unfertilized plot there was an increase from 38 to 80%.
Ten-year Growth Response of Black Spruce to Thinning and Fertilization Treatments
Authors: Weetman G. F.
Published: September 2010

A 65-year-old upland black spruce (Piceamariana Mill. B.S.P.) stand near Baie Comeau, Quebec, was thinned and fertilized with urea; each treatment was at 2 levels in a split plot factorial design. The trees responded to the nitrogen addition after 1 year and to thinning after 7 years. The trees were still growing faster in response to most treatments after 10 years. Trees of all size classes responded to the treatments. The periodic increment was not increased by 25% thinning, but was increased by 50% thinning and was always increased by nitrogen additions. Absolute increases over control values ranged from 130 to 290 ft3 (11 to 24.6 m3) for an application of 100 lb N per acre (112 kg N per hectare) and 238 to 297 ft3 (20 to 25.2 m3) for 400 lb N per acre (444 kg N per hectare) (1 ha = 104 m2). Some synergistic effect of combined thinning and fertilizer treatments is indicated.Mortality losses in the 10-year period were appreciable because of excessive stand density. The roles of thinning and fertilizer treatments in black spruce management are discussed.
Sampling Deciduous Broadleaved Trees for the Determination of Leaf Weight and Foliar Elemental Concentrations
Authors: Ellis Robert C.
Published: September 2010

Foliar samples, collected from forest-grown trees of sugar maple (Acersaccharum Marsh.), white ash (Fraxinusamericana L.), and black cherry (Prunusserotina Ehrh.), were analyzed for mean weight per leaf and for concentrations of N, P, K, Ca, Mg, Mn, and Zn. The data were subjected to analysis of variance among branches within trees, among trees within stands, and among stands. Among stands of a species, differences in mean concentration of 20% of the range reported in the literature could be detected (P = 0.05) for most elements by sampling foliage from two small branches taken from the midcrown of each of 15 trees per stand.
The Effect of Temperature and Stratification on Germination in Selected Members of the Salicaceae in Interior Alaska
Authors: Zasada J. C. , Viereck L. A.
Published: September 2010

Alaskan Salicaceae can be subdivided into two groups on the basis of timing of seed dispersal. The early-seeding species include members of the genus Populus and the majority of Salix species. Late-seeding species include seven members of the genus Salix. On tests of five species, the seed of four early-seeding species germinated completely at temperatures of 25,20,15,10, and 5 °C. The seed of one late-seeding species germinated completely only after stratification and then only at 25, 20, and 15 °C. [Traduit par le journal]
Frost Hardiness Development in Rapid- and Slow-growing Norway Spruce Seedlings
Authors: Christersson Lars
Published: September 2010

Frost hardiness development was investigated in rapid-growing and slow-growing 5- to 6-month-old seedlings of Piceaabies (L.) Karst. The different growth rates, resulting from different fertilization without changing the tissue nutrient concentration, had no effect on development of frost hardiness.
TRANSPORT PROPERTIES OF SINGLE-WALLED CARBON NANOTUBE WITH INTRAMOLECULAR JUNCTIONS
Authors: ZENG HUI , HU HUIFANG , WEI JIANWEI , WANG ZHIYONG
Published: September 2010

Using density-functional theory (DFT) combined with non-equilibrium Green's function (NEGF), we have investigated the transport properties of carbon nanotubes with S–S, M–S, and M–M heterojunctions. The results show that the local states associated with topological defects arise at the junctions. The position and width of local states strongly depend on the configurations of the topological defects and their arrangement. The (7, 0)–(8, 0) and (8, 0)–(9, 0) heterojunctions present semiconducting characteristics. The (6, 0)–(9, 0) heterojunction maintains metallic properties. However, the 5/6/6/7 defects in the nanostructure decrease the electronic transport. More importantly, our results indicate that the I–V characteristics of the heterojunctions could be effectively controlled by gate voltage.
CURLICUES WITH MEMORY
Authors: ALONSO-SANZ RAMÓN
Published: September 2010

The dynamics of the curlicue curves with memory endowed in their dynamics is addressed in this study.
Sedimentary basin tectonics from the Black Sea and Caucasus to the Arabian Platform: introduction
Authors: Sosson Marc , Kaymakci Nuretdin , Stephenson Randell , Bergerat Françoise , Starostenko Vitaly
Published: September 2010

The Palaeozoic to recent evolution of the Tethys system gave way to the largest mountain chain of the world extending from the Atlantic to Pacific oceans – the Alpine–Himalayan Mountain chain, which is still developing as a result of collision and northwards convergence of continental blocks including Apulia in the west, the Afro-Arabian Plate in the middle and the Indian Plate in the east. This Special Publication addresses the main problems of the middle part of this system incorporating the Balkans, Black Sea and Greater Caucasus in the north and the Afro-Arabian Plate in the south. Since the Early Mesozoic a number of small to large scale oceanic basins opened and closed as the intervening continental fragments drifted northwards and diachronously collided with and accreted to the southern margin of the Eurasian Plate. Despite the remarkable consequences of this, in terms of subduction, obduction and orogenic processes, little is known about the timing and palaeogeographic evolution of the region. This includes the amounts of shortening and interplay between synconvergent extension and compression, development of magmatic arc and arc-related basins and the timing and mechanism of their deformation. The chapters presented in this Special Publication present new information that help to fill some of the gaps of the puzzle.
Cenozoic-Recent tectonics and uplift in the Greater Caucasus: a perspective from Azerbaijan
Authors: Mosar Jon , Kangarli Talat , Bochud Martin , Glasmacher Ulrich A. , Rast Annick , Brunet Marie-Francoise , Sosson Marc
Published: September 2010

The Greater Caucasus is Europe's highest mountain belt and results from the inversion of the Greater Caucasus back-arc-type basin due to the collision of Arabia and Eurasia. The orogenic processes that led to the present mountain chain started in the Early Cenozoic, accelerated during the Plio-Pleistocene, and are still active as shown from present GPS studies and earthquake distribution. The Greater Caucasus is a doubly verging fold-and-thrust belt, with a pro- and a retro wedge actively propagating into the foreland sedimentary basin of the Kura to the south and the Terek to the north, respectively. Based on tectonic geomorphology – active and abandoned thrust fronts – the mountain range can be subdivided into several zones with different uplift amounts and rates with very heterogeneous strain partitioning. The central part of the mountain range – defined by the Main Caucasus Thrust to the south and backthrusts to the north – forms a triangular-shape zone showing the highest uplift and fastest rates, and is due to thrusting over a steep tectonic ramp system at depth. The meridional orogenic in front of the Greater Caucasus in Azerbaijan lies at the foothills of the Lesser Caucasus, to the south of the Kura foreland basin.
The Armenian Ophiolite: insights for Jurassic back-arc formation, Lower Cretaceous hot spot magmatism and Upper Cretaceous obduction over the South Armenian Block
Authors: Rolland Y. , Galoyan G. , Sosson M. , Melkonyan R. , Avagyan A.
Published: September 2010

Similar geological, petrological, geochemical and age features are found in various Armenian ophiolitic massifs (Sevan, Stepanavan and Vedi). These data argue for the presence of a single large ophiolite unit obducted on the South Armenian Block (SAB). Lherzolite Ophiolite type rock assemblages evidence a Lower–Middle Jurassic slow-spreading rate. The lavas and gabbros have a hybrid geochemical composition intermediate between arc and Mid Ocean Ridge Basalt (MORB) signatures which suggest they were probably formed in a back-arc basin. This oceanic sequence is overlain by pillowed alkaline lavas emplaced in marine conditions. Their geochemical composition is similar to plateau-lavas. Finally, this thickened oceanic crust is overlain by Upper Cretaceous calc-alkaline lavas likely formed in a supra-subduction zone environment. The age of the ophiolite is constrained by
40
Ar/
39
Ar dating experiments provided a magmatic crystallization age of 178.7±2.6 Ma, and further evidence of greenschist facies crystallization during hydrothermal alteration until
c
. 155 Ma. Thus, top-to-the-south obduction likely initiated along the margin of the back-arc domain, directly south of the Vedi oceanic crust, and was transported as a whole on the SAB in the Coniacian times (88–87 Ma). Final closure of the basin is Late Cretaceous in age (73–71 Ma) as dated by metamorphic rocks.
Late Cretaceous to Recent kinematics of SE Anatolia (Turkey)
Authors: Kaymakci N. , Inceöz M. , Ertepinar P. , Koç A.
Published: September 2010

Five different deformation phases have been recognized in the SE Anatolian orogen and the Arabian Platform based on palaeostress inversion studies using fault-slip data sets. The timing and duration of these phases are determined using various criteria including the age of the affected strata, syndepositional structures, cross-cutting structures and overprinting slickensides. The oldest deformation phase is characterized generally by NE–SW-directed extension. The extension is thought to have resulted from slab-roll back processes during the Maastrichtian to Middle Eocene interval (
c
. 60 Ma to 40–35 Ma). The second deformation phase is characterized by east–west to NW–SE-directed compression and thought to result from cessation of roll-back processes possibly due to subduction of younger oceanic crust or increase in the convergence rate between Africa and Eurasia during the post-Middle Eocene to Late Oligocene interval (
c
. 40–35 Ma to 25 Ma). The third deformation phase is characterized by east–west to NW–SE-directed extension possibly due to slab detachment that initiated in Iran and migrated westwards during the latest Oligocene to Middle Miocene period (25–11 Ma). The fourth deformation phase is characterized by approximately north–south-directed compression due to collision and further northwards indentation of Arabian Plate by the end of Middle Miocene (11–3.5 Ma). The fifth and present deformation phase is characterized by NE–SW compression which might result from tectonic re-organization in the region since the Middle Pliocene (
c
. 3.5 Ma to recent).
Alpine high pressure evolution of the eastern Bitlis complex, SE Turkey
Authors: Oberhänsli R. , Candan O. , Bousquet R. , Rimmele G. , Okay A. , Goff J.
Published: September 2010

The Bitlis complex, SE Anatolia, constitutes a crystalline complex derived from the north of the Arabian Plate, accreted to the South Armenian block. Metamorphic studies in the cover sequences of the Bitlis complex allow constraining the thermal evolution of the massif by metamorphic index minerals. A regionally distributed low temperature-high pressure (LT-HP) metamorphic evolution is documented by glaucophane, relics of carpholite in chloritoid-bearing schists and pseudomorphs after aragonite in marbles. The metamorphic age of these HP assemblages is constrained by Ar isotope dating as 74±2 Ma. This indicates that (i) the Bitlis complex represents a terrane detached from the Arabian indenter that was subducted and stacked to form a nappe complex during the closure of the Neo-Tethys and (ii) that during Late Cretaceous to Cenozoic evolution the Bitlis complex never underwent temperatures over 450 °C. The consequences of the metamorphic evolution of the Bitlis complex (a cold continental block within a hot environment) for the Eastern Anatolian plateau are complied in a crustal section.
Seismic sequence stratigraphy, structure and subsidence history of the Romanian Black Sea shelf
Authors: Konerding Catalina , Dinu Corneliu , Wong How Kin
Published: September 2010

The Black Sea is an extensional back-arc basin developed along the northern active margin of the Tethys Ocean which was subducted northward from the Triassic to Miocene times. The Romanian Black Sea shelf is dominated by mid-Cretaceous extensional structures and their sedimentary cover, subsequently affected by Cenozoic compression. Here we analyse the post-Oligocene structural and sedimentological evolution of the shelf, based on Romanian oil industry data consisting of (1) 5300 line-km reflection seismic profiles situated on the shelf and continental slope; and (2) depth and lithostratigraphic information from 60 boreholes on the shelf. Our study provides evidence for a changing evolution of the shelf during a relatively short period of time directly related to the pre-Miocene period and the evolution of the Romanian onshore. Mio-Pleistocene subsidence of the Romanian Black Sea shelf is highly variable and is directly dependent on sediment input, tectonic activity as well as water-level fluctuations. Subsidence during the Badenian–Sarmatian and the Dacian–Quaternary was limited. In contrast, during the Pontian, shelf subsidence was progressively faster in the basinward direction. Subsidence on the outer shelf was much more significant than elsewhere on the shelf. Tectonically, the most active period during the Mio-Pleistocene was the Pontian. The Badenian–Sarmatian was largely quiescent and the Dacian–Quaternary saw a decrease in the Pontian tectonic activity, coming possibly even to a halt. From a sequence-stratigraphical point of view, eight systems tracts were identified for the Mio-Pleistocene sedimentary section. The Badenian-Sarmatian unit was attributed to a HST (highstand systems tract). The Pontian unit was subdivided into P1, P2, P3 and P4. Subunit P1, which was laid down on the slope at the time of deposition, is progradational and attributable to the lowstand wedge of a LST (lowstand systems tract). Subunit P2 is likewise also attributed to a LST, having the continental slope and the deep basin as palaeo-depositional environments. The reflection terminations and the wedge-shape of P3 suggest that it was deposited in the deep basin during a sea level lowstand. The next transgressive systems tract (TST) and HST developed during the deposition of P4. The boundary between P4 and the Dacian is represented by an erosional hiatus, which comprises the LST that follows the formation of the sequence boundary at the end of the Pontian. During the Dacian–Quaternary, the subsequent TST and HST were deposited on the inner and middle shelves. Sedimentation on the Romanian shelf during the Mio-Pleistocene period was thus strongly influenced by sediment input and subsidence, while sea level fluctuations played a lesser role. As sediment input is related to the evolution of the adjacent land and subsidence is dependent on sediment supply, tectonic activity and sea level fluctuations, these two factors are not totally independent.
Dimensioning and worst-case analysis of cluster-tree sensor networks
Authors: Jurcik Petr , Koubâa Anis , Severino Ricardo , Alves Mário , Tovar Eduardo
Published: September 2010

Modeling the fundamental performance limits of Wireless Sensor Networks (WSNs) is of paramount importance to understand their behavior under the worst-case conditions and to make the appropriate design choices. This is particular relevant for time-sensitive WSN applications, where the timing behavior of the network protocols (message transmission must respect deadlines) impacts on the correct operation of these applications. In that direction this article contributes with a methodology based on Network Calculus, which enables quick and efficient worst-case dimensioning of static or even dynamically changing cluster-tree WSNs where the data sink can either be static or mobile. We propose closed-form recurrent expressions for computing the worst-case end-to-end delays, buffering and bandwidth requirements across any source-destination path in a cluster-tree WSN. We show how to apply our methodology to the case of IEEE 802.15.4/ZigBee cluster-tree WSNs. Finally, we demonstrate the validity and analyze the accuracy of our methodology through a comprehensive experimental study using commercially available technology, namely TelosB motes running TinyOS.
Not all wireless sensor networks are created equal
Authors: Mottola Luca , Picco Gian Pietro , Ceriotti Matteo , Gunǎ Ştefan , Murphy Amy L.
Published: September 2010

Wireless sensor networks (WSNs) are envisioned for a number of application scenarios. Nevertheless, the few in-the-field experiences typically focus on the features of a specific system, and rarely report about the characteristics of the target environment, especially with respect to the behavior and performance of low-power wireless communication. The TRITon project, funded by our local administration, aims to improve safety and reduce maintenance costs of road tunnels, using a WSN-based control infrastructure. The access to real tunnels within TRITon gives us the opportunity to experimentally assess the peculiarities of this environment, hitherto not investigated in the WSN field. We report about three deployments: (i) an operational road tunnel, enabling us to assess the impact of vehicular traffic; (ii) a nonoperational tunnel, providing insights into analogous scenarios (e.g., underground mines) without vehicles; (iii) a vineyard, serving as a baseline representative of the existing literature. Our setup, replicated in each deployment, uses mainstream WSN hardware, and popular MAC and routing protocols. We analyze and compare the deployments with respect to reliability, stability, and asymmetry of links, the accuracy of link quality estimators, and the impact of these aspects on MAC and routing layers. Our analysis shows that a number of criteria commonly used in the design of WSN protocols do not hold in tunnels. Therefore, our results are useful for designing networking solutions operating efficiently in similar environments.
HCI Education to Support Collaborative e-Learning Systems Design
Authors: Lambropoulos Niki , Culwin Fintan , Romero Margarida
Published: September 2010

Anytime, anywhere e-learning, requires tools to support e-learners in the management of their learning objectives and activities. Collaborative e-learning requires tools that support participants as both learners and users (Smulders, 2002). Being users as well as learners, e-learners interact in a complex space which includes the tools, their peers and their e-tutors. Contextual information from the interactions can improve e-learners' awareness, organizational and learning activities. Therefore tools need to support e-learners by exposing the contextual information within the interactional space.
Regulation of Antitumor Immune Responses by the IL‐12 Family Cytokines, IL‐12, IL‐23, and IL‐27
Authors: Xu Mingli , Mizoguchi Izuru , Morishima Noriko , Chiba Yukino , Mizuguchi Junichiro , Yoshimoto Takayuki
Published: September 2010

The interleukin (IL)‐12 family, which is composed of heterodimeric cytokines including IL‐12, IL‐23, and IL‐27, is produced by antigen‐presenting cells such as macrophages and dendritic cells and plays critical roles in the regulation of helper T (Th) cell differentiation. IL‐12 induces IFN‐γ production by NK and T cells and differentiation to Th1 cells. IL‐23 induces IL‐17 production by memory T cells and expands and maintains inflammatory Th17 cells. IL‐27 induces the early Th1 differentiation and generation of IL‐10‐producing regulatory T cells. In addition, these cytokines induce distinct immune responses to tumors. IL‐12 activates signal transducers and activator of transcription (STAT)4 and enhances antitumor cellular immunity through interferon (IFN)‐γ production. IL‐27 activates STAT1, as does IFN‐γ and STAT3 as well, and enhances antitumor immunity by augmenting cellular and humoral immunities. In contrast, although exogenously overexpressed IL‐23 enhances antitumor immunity via memory T cells, endogenous IL‐23 promotes protumor immunity through STAT3 activation by inducing inflammatory responses including IL‐17 production.
Electroacupuncture Inhibits Inflammation Reaction by Upregulating Vasoactive Intestinal Peptide in Rats with Adjuvant‐Induced Arthritis
Authors: He Tian-Feng , Yang Wen-Jia , Zhang Shu-hui , Zhang Chun-Yan , Li Lian-Bo , Chen Yun-Fei
Published: September 2010

Acupuncture is emerging as an alternative therapy for rheumatoid arthritis (RA). However, the molecular mechanism underlying this beneficial effect of acupuncture has not been fully understood. Here, we demonstrated that electroacupuncture at acupoints Zusanli (ST36), Xuanzhong (GB39); and Shenshu (BL23) markedly decreased the paw swelling and the histologic scores of inflammation in the synovial tissue, and reduced the body weight loss in an adjuvant‐induced arthritis rat model. However, the electrical stimulation at nonacupoint did not produce any beneficial effects against the experimental arthritis. Most interestingly, the electroacupuncture treatment resulted in an enhanced immunostaining for vasoactive intestinal peptide (VIP), a potent anti‐inflammatory neuropeptide, in the synovial tissue. Moreover, the VIP‐immunostaining intensity was significantly negatively correlated with the scores of inflammation in the synovial tissue (r = −0.483, P = .0026). In conclusion, these findings suggest that electroacupuncture may offer therapeutic benefits for the treatment of RA, at least partially through the induction of VIP expression.
Integrated Microfluidic and Imaging Platform for a Kinase Activity Radioassay to Analyze Minute Patient Cancer Samples
Authors: Fang Cong , Wang Yanju , Vu Nam T. , Lin Wei-Yu , Hsieh Yao-Te , Rubbi Liudmilla , Phelps Michael E. , Müschen Markus , Kim Yong-Mi , Chatziioannou Arion F. , Tseng Hsian-Rong , Graeber Thomas G.
Published: September 2010

Oncogenic kinase activity and the resulting aberrant growth and survival signaling are a common driving force of cancer. Accordingly, many successful molecularly targeted anticancer therapeutics are directed at inhibiting kinase activity. To assess kinase activity in minute patient samples, we have developed an immunocapture-based in vitro kinase assay on an integrated polydimethylsiloxane microfluidics platform that can reproducibly measure kinase activity from as few as 3,000 cells. For this platform, we adopted the standard radiometric 32P-ATP–labeled phosphate transfer assay. Implementation on a microfluidic device required us to develop methods for repeated trapping and mixing of solid-phase affinity microbeads. We also developed a solid-state beta-particle camera imbedded directly below the microfluidic device for real-time quantitative detection of the signal from this and other microfluidic radiobioassays. We show that the resulting integrated device can measure ABL kinase activity from BCR-ABL–positive leukemia patient samples. The low sample input requirement of the device creates new potential for direct kinase activity experimentation and diagnostics on patient blood, bone marrow, and needle biopsy samples. Cancer Res; 70(21); 8299–308. ©2010 AACR.
Angiotensin-(1-7) Reduces Fibrosis in Orthotopic Breast Tumors
Authors: Cook Katherine L. , Metheny-Barlow Linda J. , Tallant E. Ann , Gallagher Patricia E.
Published: September 2010

Angiotensin-(1-7) [Ang-(1-7)] is an endogenous 7–amino acid peptide hormone of the renin-angiotensin system that has antiproliferative properties. In this study, Ang-(1-7) inhibited the growth of cancer-associated fibroblasts (CAF) and reduced fibrosis in the tumor microenvironment. A marked decrease in tumor volume and weight was observed in orthotopic human breast tumors positive for the estrogen receptor (BT-474 or ZR-75-1) and HER2 (BT-474) following Ang-(1-7) administration to athymic mice. Ang-(1-7) concomitantly reduced interstitial fibrosis in association with a significant decrease in collagen I deposition, along with a similar reduction in perivascular fibrosis. In CAFs isolated from orthotopic breast tumors, the heptapeptide markedly attenuated in vitro growth as well as reduced fibronectin, transforming growth factor-β (TGF-β), and extracellular signal-regulated kinase 1/2 kinase activity. An associated increase in the mitogen-activated protein kinase (MAPK) phosphatase DUSP1 following treatment with Ang-(1-7) suggested a potential mechanism by which the heptapeptide reduced MAPK signaling. Consistent with these in vitro observations, immunohistochemical analysis of Ang-(1-7)–treated orthotopic breast tumors revealed reduced TGF-β and increased DUSP1. Together, our findings indicate that Ang-(1-7) targets the tumor microenvironment to inhibit CAF growth and tumor fibrosis. Cancer Res; 70(21); 8319–28. ©2010 AACR.
Analysis of the Yield of Phase II Combination Therapy Trials in Medical Oncology
Authors: Maitland Michael L. , Hudoba Christine , Snider Kelly L. , Ratain Mark J.
Published: September 2010

Purpose: Phase II clinical studies screen for treatment regimens that improve patient care, but screening combination regimens is especially challenging. We hypothesized that recognized flaws of single-arm trials could be magnified in combination treatment studies, leading to many reported positive phase II trials but with a low fraction resulting in practice-changing phase III trials.

Experimental Design: We searched medline and identified 363 combination chemotherapy clinical trials published in 2001 and 2002. Studies were rated as positive, negative, or inconclusive based on a standardized review of abstract and text. The Web of Science Index (Thomson Reuters, NY, NY) was searched for all articles published between January 2003 and October 2007 that cited at least one of these 363 published trials.

Results: Of 363 published phase II combination chemotherapy trials, 262 (72%) were declared to be positive. Among 3,760 unique subsequent citing papers, 20 reported randomized phase III trials of the same combination in the same disease as the source paper, and 10 of these resulted in improved standards of care. Estimating from these data, the likelihood that a published, positive phase II combination chemotherapy trial will result in a subsequent trial showing an improvement in standard of care within five years was 0.038 (95% confidence interval, 0.016-0.064).

Conclusions: The contributory value of combination chemotherapy phase II trials done by 2001-2002 standards is low despite the participation of more than 16,000 subjects. Future phase II studies of combination regimens require better methods to screen for treatments most likely to improve standards of care. Clin Cancer Res; 16(21); 5296–302. ©2010 AACR.
Early Impairment of Transmural Principal Strains in the Left Ventricular Wall After Short-Term, High-Fat Feeding of Mice Predisposed to Cardiac Steatosis
Authors: Hankiewicz Janusz H. , Banke Natasha H. , Farjah Mariam , Lewandowski E. Douglas
Published: September 2010

Background—

Myocardial lipid accumulation precedes some cardiomyopathies, but little is known of concurrent effects on ventricular mechanics. We tested the hypothesis that intramyocardial lipid accumulation during a short-term, high-fat diet (HFD) affects 2-dimensional strains in the heart. We examined the hearts of nontransgenic (NTG) mice and of transgenic mice predisposed to elevated triacylglyceride (TAG) storage linked to low-level overexpression of peroxisome proliferator activated receptor (PPAR-α).

Methods and Results—

Myocardial lipid and transmural principal strains E1 and E2 were determined in vivo with
1
H magnetic resonance spectroscopy/imaging before and after 2 weeks of an HFD in both PPAR-α and NTG littermate mice. Baseline lipid was elevated in PPAR-α compared with NTG mice. An HFD increased mobile lipid by 174% in NTG mice (
P
<0.05) and by 79% in PPAR-α mice (
P
<0.05). After an HFD, lipid and TAG were higher in PPAR-α versus NTG mice by 63% and 81%, respectively. However, TAG in PPAR-α mice after an HFD was similar to TAG in PPAR-α mice fed a regular diet, suggesting that the magnetic resonance spectroscopy signal from lipid is not exclusive to TAG. Only at the highest lipid contents, achieved in PPAR-α mice, were strains affected. Endocardial strain was most compromised, with a negative correlation to lipid (
P
<0.05).

Conclusions—

A short-term HFD elevated myocardial lipid measures as determined by magnetic resonance spectroscopy, which became dissociated from TAG content in hearts predisposed to cardiac steatosis. The increased lipid was associated with concurrent, transmural reductions in E1 and E2 strains across the left ventricular wall. Strains were attenuated at the highest levels of lipid accumulation, suggesting a threshold response. Thus, 2-dimensional strains are impaired early and without left ventricular diastolic dysfunction, owing to cardiac steatosis.
Long-Term Recording of Cardiac Arrhythmias With an Implantable Cardiac Monitor in Patients With Reduced Ejection Fraction After Acute Myocardial Infarction
Authors: Bloch Thomsen Poul Erik , Jons Christian , Raatikainen M.J. Pekka , Moerch Joergensen Rikke , Hartikainen Juha , Virtanen Vesa , Boland J. , Anttonen Olli , Gang Uffe Jakob , Hoest Nis , Boersma Lucas V.A. , Platou Eivin S. , Becker Daniel , Messier Marc D. , Huikuri Heikki V. ,   for the Cardiac Arrhythmias and Risk Stratification After Acute Myocardial Infarction (CARISMA) Study Group
Published: September 2010

Background—

Knowledge about the incidence of cardiac arrhythmias after acute myocardial infarction has been limited by the lack of traditional ECG recording systems to document and confirm asymptomatic and symptomatic arrhythmias. The Cardiac Arrhythmias and Risk Stratification After Myocardial Infarction (CARISMA) trial was designed to study the incidence and prognostic significance of arrhythmias documented by an implantable cardiac monitor among patients with acute myocardial infarction and reduced left ventricular ejection fraction.

Methods and Results—

A total of 1393 of 5869 patients (24%) screened in the acute phase (3 to 21 days) of an acute myocardial infarction had left ventricular ejection fraction ≤40%. After exclusions, 297 patients (21%) (mean±SD age, 64.0±11.0 years; left ventricular ejection fraction, 31±7%) received an implantable cardiac monitor within 11±5 days of the acute myocardial infarction and were followed up every 3 months for an average of 1.9±0.5 years. Predefined bradyarrhythmias and tachyarrhythmias were recorded in 137 patients (46%); 86% of these were asymptomatic. The implantable cardiac monitor documented a 28% incidence of new-onset atrial fibrillation with fast ventricular response (≥125 bpm), a 13% incidence of nonsustained ventricular tachycardia (≥16 beats), a 10% incidence of high-degree atrioventricular block (≤30 bpm lasting ≥8 seconds), a 7% incidence of sinus bradycardia (≤30 bpm lasting ≥8 seconds), a 5% incidence of sinus arrest (≥5 seconds), a 3% incidence of sustained ventricular tachycardia, and a 3% incidence of ventricular fibrillation. Cox regression analysis with time-dependent covariates revealed that high-degree atrioventricular block was the most powerful predictor of cardiac death (hazard ratio, 6.75; 95% confidence interval, 2.55 to 17.84;
P
<0.001).

Conclusions—

This is the first study to report on long-term cardiac arrhythmias recorded by an implantable loop recorder in patients with left ventricular ejection fraction ≤40% after myocardial infarction. Clinically significant bradyarrhythmias and tachyarrhythmias were documented in a substantial proportion of patients with depressed left ventricular ejection fraction after acute myocardial infarction. Intermittent high-degree atrioventricular block was associated with a very high risk of cardiac death.

Clinical Trial Registration—

URL:
http://www.ClinicalTrials.gov
, Unique identifier: NCT00145119.
Volume-Outcome Relationships and Abdominal Aortic Aneurysm Repair
Authors: Landon Bruce E. , O'Malley A. James , Giles Kristina , Cotterill Philip , Schermerhorn Marc L.
Published: September 2010

Background—

There is a well-established literature relating procedure volume to outcomes, but incorporating such information into clinical decision making is problematic when there is >1 treatment option for a condition.

Methods and Results—

We used data from the Medicare program to investigate the relationship between institutional volume for open and endovascular abdominal aortic aneurysm (AAA) repair and outcomes, examine trends in volume, and explore the implications for physicians making referrals for AAA repair. Trends in institutional volume were measured for the time period 2001–2006, whereas outcomes were assessed with the use of a previously assembled propensity score–matched cohort covering the time period 2001–2004. Between 2001 and 2006, there were a total of 230 736 repairs of either an intact or ruptured AAA for traditional Medicare beneficiaries. During this time, the proportion of endovascular cases increased from ≈22 in 2001 to >50 of AAA repairs in 2006, but there was little shift in procedure volume to high-volume institutions. For endovascular repair, adjusted mortality by quintile showed a marked decrease between the first and second quintile, with continued smaller decreases over quintiles 3 to 5. For open repair, adjusted mortality showed a steady decrease across the quintiles of volume.

Conclusions—

We found a steady increase in survival with increasing volume of open repair but relatively little improvement after reaching a relatively low threshold for endovascular repair. Because hospital experience with one repair method does not translate into improved outcomes for the alternative method, referring clinicians must consider both treatment options when making referral decisions.