bluuebunny/crossref_metadata_2025 huggingface dataset:
Gene Expression Profiles of Immune Mediators and Histopathological Findings in Animal Models of Leptospirosis: Comparison between Susceptible Hamsters and Resistant Mice
Authors: Matsui Mariko , Rouleau Vincent , Bruyère-Ostells Lilian , Goarant Cyrille
Published: August 2011

Leptospirosis is a widespread zoonosis characterized by multiple organ failure and variable host susceptibility toward pathogenic
Leptospira
strains. In this study, we put the role of inflammatory mediators in parallel with bacterial burdens and organ lesions by comparing a susceptible animal model, the hamster, and a resistant one, the Oncins France 1 (OF1) mouse, both infected with virulent
Leptospira interrogans
serovar Icterohaemorrhagiae strain Verdun. Histological observations evidenced edema, congestion, hemorrhage, and inflammatory infiltration in the organs of hamsters, in contrast to limited changes in mice. Using reverse transcription-quantitative PCR techniques, we showed that the relative
Leptospira
burden progressively increased in hamster tissues, while a rapid clearance was observed in mouse tissues. The early regulation of the proinflammatory mediators interleukin-1β (IL-1β), IL-6, tumor necrosis factor alpha, and cyclo-oxygenase-2 and the chemokines gamma interferon-inducible protein 10 kDa/CXCL10 and macrophage inflammatory protein-1α/CCL3 in mouse tissues contrasted with their delayed and massive overexpression in hamster tissues. Conversely, the induction of the anti-inflammatory cytokine IL-10 was faster in the resistant than in the susceptible animal model. The role of these cytokines in the pathophysiology of leptospirosis and the implications of their differential regulation in the development of this disease are discussed.
Fate of manuscripts rejected by a non-English-language general medical journal: a retrospective cohort study
Authors: Vinther Siri , Rosenberg Jacob
Published: August 2011

Objective

The objective of this study was to determine whether, where and when manuscripts were published following rejection by theJournal of the Danish Medical Association, a general medical journal published in Danish. Similar previous studies have focused on specialty/subspecialty journals published in English.

Design

Manuscripts rejected during a 4-year period were searched for in PubMed and Embase in order to assess the percentage of manuscripts subsequently published in other journals. In addition, characteristics of both the published manuscripts and the journals in which they were evaluated.

Results

Of 198 rejected manuscripts, 21 (10.6%) were eventually published after a median of 685 days (range 209–1463). The majority of these were original research, published in English-language specialty/subspecialty journals. The median number of citations per article was 2–3 (IQR 0.5–9.5, depending on the database searched).

Conclusions

10.6% of the rejected manuscripts were eventually published in other journals, mainly English-language specialty journals. This proportion was considerably lower than that for other journals that have studied the fate of rejected manuscripts. Manuscript translation could be a barrier for resubmitting to English-language journals with larger readerships, thus hindering the dissemination of knowledge to the international community.
Coffee plant – pollinator interactions: a review
Authors: Ngo H.T. , Mojica A.C. , Packer L.
Published: August 2011

Coffee (genus Coffea  L.) is one of the most critical global agricultural crops. Many studies have focused on coffee plants and their associated insects. This review will summarize work specifically relating to coffee plant – pollinator interactions. We review the current status of coffee as a worldwide commodity, botanical aspects of coffee, and insects associated with coffee pollination, and we assess the current understanding of the role of different pollinator taxa in increasing fruit set and yield.
Benefits and costs ofLeptophlebia(Ephemeroptera) mayfly movements between river channels and floodplain wetlands
Authors: Galatowitsch M.L. , Batzer D.P.
Published: August 2011

Dramatic drift of nymphs of the mayflies Leptophlebia Westwood, 1840 and Siphlonurus Eaton, 1868 (47 600 individuals/trap per hour) was observed between a southeastern USA river and adjacent floodplain following natural flooding events. Active movements of these nymphs against the water flow were also detected. Large numbers of leptophlebid nymphs reside in floodplains during the winter and spring, but how and why they colonize and develop in temporary habitats is uncertain. We detected few environmental advantages (i.e., temperature, food abundance or quality) for mayflies in floodplains compared with river habitats. Despite this, experiments indicated that mayflies had 36% higher growth rates in the floodplain than in the river and demonstrated tolerance to short-term drying (up to 12 d). Migration entails costs of migrating against flows during daylight when vulnerability to predation is high, colonizing a habitat subject to drying, hypoxia, and supporting amphibian predators, with few apparent benefits. Dispersal into wetlands may be attributed to avoiding swift river flows or exploiting largely fishless habitats. However, dispersal could be an evolutionary relic of behavior beneficial in more northerly habitats; our study populations of Leptophlebia mayflies were at the southern extreme of their range and perhaps operating suboptimally. Our results emphasize the importance of river–floodplain linkages to the ecology of both habitats.
ANTIBACTERIAL AND BIOCOMPATIBILITY PROPERTIES OF NANO-SILVER/TITANIA THIN LAYER
Authors: EMADI R. , RAEISSI K.
Published: August 2011

Ag/TiO2coating was prepared by anodizing the surface of Ti followed by electrodeposition of silver. By X-ray diffraction (XRD) analyses, that indicated the crystalline size of Ag deposit onto the oxidized surface of Ti was around 32 nm. Scanning electron microscopy (SEM) images of the oxidized surface with and without Ag deposit show that TiO2is formed uniformly but Ag deposit consisted of numerous spherical structures. The Escherichia coli and Staphylococcus aureus bacteria were utilized to test the antibacterial effect of Ag/TiO2coating which showed more than 99% of bacteria were killed after 24 h incubation. The results of in vitro test showed Ag/TiO2coating is also biocompatible.
PHONON-DRAG EFFECT OF ULTRA-THIN FeSi2 AND MnSi1.7/FeSi2 FILMS
Authors: HOU Q. R. , GU B. F. , CHEN Y. B. , HE Y. J.
Published: August 2011

Phonon-drag effect usually occurs in single crystals at very low temperatures (10–200 K). Strong phonon-drag effect is observed in ultra-thin β- FeSi 2 films at around room temperature. The Seebeck coefficient of a 23 nm-thick β- FeSi 2 film can reach -1.375 mV/K at 343 K. However, the thermoelectric power factor of the film is still small, only 0.42×10-3 W/m-K2, due to its large electrical resistivity. When a 27 nm-thick MnSi 1.7 film with low electrical resistivity is grown on it, the thermoelectric power factor of the MnSi 1.7 film can reach 1.5×10-3 W/m-K2 at around room temperature. This value is larger than that of bulk MnSi 1.7 material in the same temperature range.
A WIKIPEDIA-BASED FRAMEWORK FOR COLLABORATIVE SEMANTIC ANNOTATION
Authors: FERNÁNDEZ N. , FISTEUS J. A. , FUENTES D. , SÁNCHEZ L. , LUQUE V.
Published: August 2011

The semantic web aims at automating web data processing tasks that nowadays only humans are able to do. To make this vision a reality, the information on web resources should be described in a computer-meaningful way, in a process known as semantic annotation. In this paper, a manual, collaborative semantic annotation framework is described. It is designed to take advantage of the benefits of manual annotation systems (like the possibility of annotating formats difficult to annotate in an automatic manner) addressing at the same time some of their limitations (reduce the burden for non-expert annotators). The framework is inspired by two principles: use Wikipedia as a facade for a formal ontology and integrate the semantic annotation task with common user actions like web search. The tools in the framework have been implemented, and empirical results obtained in experiences carried out with these tools are reported.
LEARNING PROCESS BEHAVIOR FOR FAULT DETECTION
Authors: PEREIRA CÁSSIO M. M. , DE MELLO RODRIGO F.
Published: August 2011

Recently, there has been an increased interest in self-healing systems. These types of systems are able to cope with failures in the environment they execute and work continuously by taking proactive actions to correct these problems. The detection of faults plays a prominent role in self-healing systems, as faults are the original causes of failures. Fault detection techniques proposed in the literature have been based on three mainstream approaches: process heartbeats, statistical analysis and machine learning. However, these approaches present limitations. Heartbeat-based techniques only detect failures, not faults. Statistical approaches generally assume linear models. Most machine learning techniques assume the data is independent and identically distributed. In order to overcome all these limitations we propose a new approach to address fault detection, which also gives insight into how process behavior changes over time in the presence of faults. Experiments show that the proposed approach achieves a twofold increase in F -measure when compared to Support Vector Machines (SVM) and Auto-Regressive Integrated Moving Average (ARIMA).
A COMPARATIVE STUDY OF THE EXPERIMENTAL AND SIMULATED VALUES OF MULTIFRACTAL SPECIFIC HEAT IN 14.5A GeV/c HEAVY-ION COLLISION
Authors: KAMAL ARSHAD , AHMAD N. , KHAN M. M. , AZMI M. D. , KHAN A. R. , ZAFAR M. , IRFAN M.
Published: August 2011

An attempt is made to study multifractal specific heat from Fq, modified Gq and Takagi moments, which can provide some interesting information about event-by-event fluctuations in heavy-ion collisions at high energies. It is an established fact that constancy of the specific heat (CSH) of solids and gases helps explain thermodynamical behavior of intermittency and multifractality in A–A collisions at different projectile energies. It is worthmentioning that the present paper deals with multifractal specific heat, c, extracted from Fq, modified Gq and Takagi moments for the experimental as well as FRITIOF generated data on 14.5A GeV /c28 Si -nucleus interactions. The results obtained using the three approaches are compared for both the data sets. The observed power law behavior reflects self-similar property of the multiparticle production process. The common feature of the multifractal specific heat obtained using the three approaches is that there is no systematic variation in its value for different orders of the moments. Furthermore, the value of c is found to be different for both the data sets and no strong target mass dependence is observed in any of the cases. A noteworthy observation is that a non-zero finite value of the multifractal specific heat may be considered a good signal for the presence of multifractality in the relativistic charged particle multiplicity distribution.
TWO-SIDED CHAIN CONDITIONS IN LEAVITT PATH ALGEBRAS OVER ARBITRARY GRAPHS
Authors: ABRAMS GENE , BELL JASON P. , COLAK PINAR , RANGASWAMY KULUMANI M.
Published: August 2011

Let E be any directed graph, and K be any field. For any ideal I of the Leavitt path algebra LK(E) we provide an explicit description of a set of generators for I. This description allows us to classify the two-sided noetherian Leavitt path algebras over arbitrary graphs. This extends similar results previously known only in the row-finite case. We provide a number of additional consequences of this description, including an identification of those Leavitt path algebras for which all two-sided ideals are graded. Finally, we classify the two-sided artinian Leavitt path algebras over arbitrary graphs.
BASES OF TOTAL WITT GROUPS AND LAX-SIMILITUDE
Authors: BALMER PAUL , CALMÈS BAPTISTE
Published: August 2011

We explain how to work with total Witt groups, more specifically, how to circumvent the classical embarrassment of making choices for line bundles up to isomorphisms and up to squares.
GAUGE DEFORMATIONS FOR HOPF ALGEBRAS WITH THE DUAL CHEVALLEY PROPERTY
Authors: ARDIZZONI ALESSANDRO , BEATTIE MARGARET , MENINI CLAUDIA
Published: August 2011

Let A be a Hopf algebra over a field K of characteristic zero such that its coradical H is a finite-dimensional sub-Hopf algebra. Our main theorem shows that there is a gauge transformation ζ on A such that Aζ ≅ Q#H where Aζ is the dual quasi-bialgebra obtained from A by twisting its multiplication by ζ, Q is a connected dual quasi-bialgebra in [Formula: see text] and Q#H is a dual quasi-bialgebra called the bosonization of Q by H.
Structural and Electrical Properties of Solution-Processed Gallium-Doped Indium Oxide Thin-Film Transistors
Authors: Park Jee Ho , Choi Won Jin , Chae Soo Sang , Oh Jin Young , Lee Se Jong , Song Kie Moon , Baik Hong Koo
Published: August 2011

We fabricated solution-processed gallium-doped indium oxide (GIO) thin-film transistors (TFTs). The electrical property, crystallinity, and transmittance were investigated as a function of gallium content. Varying the gallium/indium ratio is found to have a significant effect on structural and electrical properties of thin films. The shrinkage of the lattice of a GIO film originates from substitution of Ga on In sites in the In2O3 lattice, which was verified by X-ray diffraction (XRD) analysis. By increasing the gallium ratio of the channel material, the GIO film shows an amorphous phase. The optimized GIO film (Ga/In= 0.35) has an electron mobility of 3.59 cm2 V-1 s-1, a threshold voltage of 0.1 V, an on/off current ratio of 8.2×107, and a subthreshold slope of 0.9 V/decade, and is highly transparent (∼92%) in the visible region.
Large Kink Characteristics in Light Output of Tunnel Injection Quantum Well Lasers
Authors: Higa Yasutaka , Nakajima Hiroshi , Sorimachi Mikio , Miyamoto Tomoyuki
Published: August 2011

A large kink in the light output versus current characteristics was observed in semiconductor lasers with a tunnel injection quantum well structure. The output power was changed from 13 to 1.9 mW under a small current increase of 0.06I
th (30 mA). The peak-to-valley (P/V) ratio of the output power was as high as 6.8. The kink current and the P/V ratio changed greatly within a monolayer thickness variation of the tunnel injection well. The kink mechanism that can be assumed was presented on the basis of the threshold current and the threshold voltage characteristics of the experimental results.
Well-in-Well Structure for High-Speed Carrier Relaxation into Quantum Wells
Authors: Higa Yasutaka , Sorimachi Mikio , Nishinome Takuya , Miyamoto Tomoyuki
Published: August 2011

A quantum-well design for controlling carrier dynamics was investigated for high-speed direct-modulation semiconductor lasers. The proposed well-in-well (WWell) structure decreases the carrier relaxation time into an active well by designing the wave function that is related to longitudinal optical phonon scattering rate. The electron relaxation time was analyzed numerically and was estimated to become 1/2–1/10 times smaller than that of a conventional quantum-well structure. This reduction of the relaxation time is effective for reducing the optical gain damping. The advantage of an asymmetrical WWell structure is also shown.
Color Polymer-Stabilized Liquid Crystal for the Optical Shutter with Fast Response Time
Authors: Hwang Kyu Young , Lee Gae Hwang , Jang Jae Eun , Jin Yong Wan , Jung Jae Eun , Lee Sang Yoon
Published: August 2011

A color-reflective optical shutter structure has been studied using polymer-stabilized liquid crystal (PSLC) devices with a specular reflector. The combined effect of an LC, a polymer, a color dye, and a specular reflector results in a high performance of a reflective-mode optical shutter as well as of a simple structure with a fast response time capable of smooth moving images. The reflectance is up to 40%, one of highest for reflective devices, whose response times are fast enough to provide video speed response (<16.6 ms). This effective and simple shutter concept can be applied in reflective-mode flexible displays and optical equipment with high performance.
Heterodyne Mixing of Sub-Terahertz Output Power from Two Resonant Tunneling Diodes Using InP Schottky Barrier Diode
Authors: Suzuki Safumi , Karashima Koichi , Ishigaki Kaname , Asada Masahiro
Published: August 2011

We report on the heterodyne of output powers from GaInAs/AlAs resonant tunneling diodes (RTDs) oscillating at around 430 GHz using a Ni–InP Schottky barrier diode (SBD) integrated with a bow-tie antenna. The RTDs have approximately the same frequencies and total output powers of 430/435 GHz and 145/148 µW, respectively. The full width at half maximum of the linewidth of the detected signal was 5 MHz. From this result, the linewidth of each RTD was estimated to be 2.5 MHz. The obtained linewidth was theoretically discussed.
Improvement of Performance in p-Side Down InGaN/GaN Light-Emitting Diodes with Graded Electron Blocking Layer
Authors: Li Zhiqiang , Lestrade Michel , Xiao Yegao , Li Zhanming Simon
Published: August 2011

Using rigorous two-dimensional (2D) finite-element simulations, we show that increasing the doping density at electron blocking layer (EBL) not only reduces the electron overflow out of the active region, but also improves the hole injection and therefore effectively enhances the light power of InGaN/GaN light-emitting diodes (LEDs). A new p-side down structure with low turn-on voltage and high light power is also proposed. By using a graded EBL layer, we show that polarization-induced hole ionization results in higher p-type doping in the EBL and higher light power. The graded EBL also improves band structure which leads to considerably low turn-on voltage.
First-Principles Calculation of the Interlayer Distance of the Two-Layer Graphene
Authors: Alam Mohammad Shafiul , Lin Jianbo , Saito Mineo
Published: August 2011

By using first principles calculations, we study the interlayer distance of the two-layer graphene. We use a recently developed van der Waals density functional theory (VDWDFT) as well as the local density approximation (LDA). Both methods give successful results for graphite; i.e., the calculated interlayer distances are comparable with the experimental value. We find that the interlayer distance of the two-layer graphene is close to that of graphite. We also find that the AA stacking structure of the two-layer graphene has higher energy than that of the AB stacking one and the layer distance of the AA stacking is larger than that of the AB stacking. It is thus suggested that the interlayer distance becomes somewhat large when the stacking deviates from the AB stacking.
Chapter 19 Geology and petroleum potential of the East Barents Sea Basins and Admiralty Arch
Authors: Klett T. R. , Pitman J. K.
Published: August 2011

The US Geological Survey (USGS) recently assessed the potential for undiscovered oil and gas resources of the East Barents Basins and Novaya Zemlya Basins and Admiralty Arch Provinces as part of the USGS Circum-Arctic Resource Appraisal. These two provinces are located NE of Scandinavia and the northwestern Russian Federation, on the Barents Sea Shelf between Novaya Zemlya to the east and the Barents Platform to the west. Three assessment units (AUs) were defined in the East Barents Basins for this study – Kolguyev Terrace Assessment Unit (AU), South Barents Basin and Ludlov Saddle AU, and North Barents Basin AU. A fourth, defined as Novaya Zemlya Basins and Admiralty Arch AU, is coincident with the Novaya Zemlya basins and Admiralty Arch Province. These AUs, all lying north of the Arctic Circle, were assessed for undiscovered, technically recoverable resources resulting in total estimated mean volumes of approximately 7.4 billion barrels of crude oil, 318 trillion cubic feet of natural gas and 1.4 billion barrels of natural gas liquids.
Chapter 35 Regional seismic interpretation of crustal framework, Canadian Arctic passive margin, Beaufort Sea, with comments on petroleum potential
Authors: Helwig James , Kumar N. , Emmet P. , Dinkelman M. G.
Published: August 2011

Three new regional 2D seismic surveys in the Beaufort Sea provide a broad, deeper view of basins and crustal structure of the Meso-Cenozoic Canadian Arctic passive margin. The seismic profiles cover 16 270 km from inner shelf to over 2000 m water depth and include areas previously unsurveyed due to sea-ice limits. The surveys cover offshore Mackenzie Delta and extend north to Latitude 74°N off Banks Island. Geological interpretation is tied to exploratory wells in the Beaufort–Mackenzie Basin that has yielded 48 oil and gas discoveries in Cretaceous–Oligocene sandstones. The entire Meso-Cenozoic passive margin wedge beyond the depocentre ties into this established petroleum system. Three segments of the margin are defined by orientation and structural styles, from typical passive margin geometry to wrench structures to a compressional foldbelt superposed on the western segment. Outboard seismic profiles image oceanic crust and the inferred extinct spreading centre of the Canada Basin. The continent–ocean boundary is interpreted using gravity data supported by deep seismic reflectors. The regional deep imaging of the tectonic architecture, structural sequence and tectonostratigraphy of each segment are major results, and advance the understanding of the geological framework of known and potential petroleum basins of the Arctic margin of Canada.
Chapter 37 U–Pb SIMS zircon geochronology of Triassic and Jurassic sandstones on northwestern Axel Heiberg Island, northern Sverdrup Basin, Arctic Canada
Authors: Omma J. E. , Pease V. , Scott R. A.
Published: August 2011

Detrital U–Pb zircon age data from five stratigraphically controlled Mesozoic sandstones collected from a relatively continuous section in northwestern Axel Heiberg Island are used to evaluate the sediment dispersal patterns and source areas of the northern Sverdrup Basin. Three distinctive provenance types are identified. Early Triassic, Late Triassic and Middle Jurassic samples are dominated by Permo-Triassic zircons and are inferred to be derived from the Taimyr Peninsula/Polar Urals, the New Siberian Islands or some unexposed source submerged beneath the Arctic Ocean. The presence of chrome spinel in these samples suggests a component of mafic–ultramafic material in the source. An Early Jurassic sample is dominated by late Neoproterozoic–early Silurian zircons, which correlate with the Caledonian and Timanian orogens of the Barents Shelf region. A Late Jurassic sample is dominated by Meso-, Palaeoproterozoic and Archaean zircons interpreted to be sourced from the Canada–Greenland shield.

Supplementary material:

Heavy mineral data (Table S1) and U–Th–Pb ion microprobe analytical data (Table S2) are available at
http://www.geolsoc.org.uk/SUP18475
.
Chapter 46 Scientific deep-sea drilling in high northern latitudes
Authors: Thiede Jörn , Eldholm Olav , Myhre Annik M.
Published: August 2011

Some 30 years ago the regional aspects of the plate tectonic history of the Norwegian–Greenland Sea and the eastern Arctic Ocean were unravelled and showed that these ocean basins had opened in early Eocene, 55–56 Ma ago. Drilling by
Glomar Challenger
in the Norwegian–Greenland Sea during Leg 38 of the Deep Sea Drilling Project confirmed the plate tectonic model and established a marine biostratigraphy framework for the region. The leg set the stage for three subsequent Ocean Drilling Program legs of thematically oriented drilling by the
Joides Resolution
. Leg 104 drilled a deep acoustic basement hole on the Vøring Plateau, which has become a legacy hole for volcanic margin studies, and provided new key information on the Northern Hemisphere Glaciation and the history of the Norwegian Current. Legs 151 and 162 addressed North Atlantic–Arctic gateways problems. During Leg 151 the
Joides Resolution
succeeded, with icebreaker support, in reaching the ice-free waters north of Svalbard, thus for the first time bringing a scientific drill ship into the Arctic Ocean. In 2004, the Integrated Ocean Drilling Program organized the mission-specific Expedition 302 to the Lomonosov Ridge in the permanently ice-covered central Arctic Ocean. Comprising a flotilla of three icebreakers, it was a major logistical venture, and resulted in a huge scientific success. The same year the deep site on the Vøring Plateau was revisited and a thermal borehole observatory installed. During these legs a large quantity of core samples has allowed the scientific community to address fundamental questions in terms of continental margin development; plate tectonics; nature of basement; marine biostratigraphy; and the temporal and spatial evolution of the high-latitude northern climate and environments. However, major challenges remain, in particular related to the deep basins, ridges and margins of the Arctic Ocean proper. The next advance in knowledge is contingent on new technology and research infrastructure both for drilling and site surveying. Presently, plans for a new research icebreaker with drilling capability are being developed, the
Aurora Borealis
project. It will allow systematic drilling in most of the permanently ice-covered basins in the high north. The northern high latitudes have been predicted to contain vast hydrocarbon resources and cooperative ventures between industry and academia may be advantageous.
Chapter 47 Extending coastal state boundaries into the central Arctic Ocean: outer continental shelves beyond 200 nautical miles and the quest for hydrocarbons
Authors: Marcussen Christian , Macnab Ron
Published: August 2011

Five Arctic coastal states – Canada, Denmark (on behalf of Greenland), Norway, Russia and the United States – are qualified to define Outer Continental Shelves beyond 200 nautical miles in the central Arctic Ocean, in accordance with the provisions of Article 76 of the UN Convention on the Law of the Sea. This paper provides an overview of recent and ongoing initiatives by those states, describing operational difficulties and offering a regional preview of possible outcomes. For the most part, the process is driven by a desire to expand national control over resources of the seabed, but recent appraisals suggest that the areas of interest are unlikely to contain significant and commercially exploitable quantities of hydrocarbons.
Chapter 8 US Geological Survey Circum-Arctic Resource Appraisal (CARA): introduction and summary of organization and methods
Authors: Charpentier Ronald R. , Gautier Donald L.
Published: August 2011

The USGS has assessed undiscovered petroleum resources in the Arctic through geological mapping, basin analysis and quantitative assessment. The new map compilation provided the base from which geologists subdivided the Arctic for burial history modelling and quantitative assessment. The CARA was a probabilistic, geologically based study that used existing USGS methodology, modified somewhat for the circumstances of the Arctic. The assessment relied heavily on analogue modelling, with numerical input as lognormal distributions of sizes and numbers of undiscovered accumulations. Probabilistic results for individual assessment units were statistically aggregated taking geological dependencies into account. Fourteen papers in this Geological Society volume present summaries of various aspects of the CARA.
Chapter 9 Oil and gas resource potential north of the Arctic Circle
Authors: Gautier Donald L. , Bird Kenneth J. , Charpentier Ronald R. , Grantz Arthur , Houseknecht David W. , Klett Timothy R. , Moore Thomas E. , Pitman Janet K. , Schenk Christopher J. , Schuenemeyer John H. , Sørensen Kai , Tennyson Marilyn E. , Valin Zenon C. , Wandrey Craig J.
Published: August 2011

The US Geological Survey recently assessed the potential for undiscovered conventional petroleum in the Arctic. Using a new map compilation of sedimentary elements, the area north of the Arctic Circle was subdivided into 70 assessment units, 48 of which were quantitatively assessed. The Circum-Arctic Resource Appraisal (CARA) was a geologically based, probabilistic study that relied mainly on burial history analysis and analogue modelling to estimate sizes and numbers of undiscovered oil and gas accumulations. The results of the CARA suggest the Arctic is gas-prone with an estimated 770–2990 trillion cubic feet of undiscovered conventional natural gas, most of which is in Russian territory. On an energy-equivalent basis, the quantity of natural gas is more than three times the quantity of oil and the largest undiscovered gas field is expected to be about 10 times the size of the largest undiscovered oil field. In addition to gas, the gas accumulations may contain an estimated 39 billion barrels of liquids. The South Kara Sea is the most prospective gas assessment unit, but giant gas fields containing more than 6 trillion cubic feet of recoverable gas are possible at a 50% chance in 10 assessment units. Sixty per cent of the estimated undiscovered oil resource is in just six assessment units, of which the Alaska Platform, with 31% of the resource, is the most prospective. Overall, the Arctic is estimated to contain between 44 and 157 billion barrels of recoverable oil. Billion barrel oil fields are possible at a 50% chance in seven assessment units. Undiscovered oil resources could be significant to the Arctic nations, but are probably not sufficient to shift the world oil balance away from the Middle East.
Long-term treadmill exercise induces neuroprotective molecular changes in rat brain
Authors: Bayod S. , del Valle J. , Canudas A. M. , Lalanza J. F. , Sanchez-Roige S. , Camins A. , Escorihuela R. M. , Pallàs M.
Published: August 2011

Exercise enhances general health. However, its effects on neurodegeneration are controversial, and the molecular pathways in the brain involved in this enhancement are poorly understood. Here, we examined the effect of long-term moderate treadmill training on adult male rat cortex and hippocampus to identify the cellular mechanisms behind the effects of exercise. We compared three animal groups: exercised (30 min/day, 12 m/min, 5 days/wk, 36 wk), handled but nonexercised (treadmill handling procedure, 0 m/min), and sedentary (nonhandled and nonexercised). Moderate long-term exercise induced an increase in IGF-1 levels and also in energy parameters, such as PGC-1α and the OXPHOS system. Moreover, the sirtuin 1 pathway was activated in both the exercised and nonexercised groups but not in sedentary rats. This induction could be a consequence of exercise as well as the handling procedure. To determine whether the long-term moderate treadmill training had neuroprotective effects, we studied tau hyperphosphorylation and GSK3β activation. Our results showed reduced levels of phospho-tau and GSK3β activation mainly in the hippocampus of the exercised animals. In conclusion, in our rodent model, exercise improved several major brain parameters, especially in the hippocampus. These improvements induced the upregulation of sirtuin 1, a protein that extends life, the stimulation of mitochondrial biogenesis, the activation of AMPK, and the prevention of signs of neurodegeneration. These findings are consistent with other reports showing that physical exercise has positive effects on hormesis.
Optimized murine lung preparation for detailed structural evaluation via micro-computed tomography
Authors: Vasilescu Dragoş M. , Knudsen Lars , Ochs Matthias , Weibel Ewald R. , Hoffman Eric A.
Published: August 2011

Utilizing micro-X-ray CT (μCT) imaging, we sought to generate an atlas of in vivo and intact/ex vivo lungs from normal murine strains. In vivo imaging allows visualization of parenchymal density and small airways (15–28 μm/voxel). Ex vivo imaging of the intact lung via μCT allows for improved understanding of the three-dimensional lung architecture at the alveolar level with voxel dimensions of 1–2 μm. μCT requires that air spaces remain air-filled to detect alveolar architecture while in vivo structural geometry of the lungs is maintained. To achieve these requirements, a fixation and imaging methodology that permits nondestructive whole lung ex vivo μCT imaging has been implemented and tested. After in vivo imaging, lungs from supine anesthetized C57Bl/6 mice, at 15, 20, and 25 cmH2O airway pressure, were fixed in situ via vascular perfusion using a two-stage flushing system while held at 20 cmH2O airway pressure. Extracted fixed lungs were air-dried. Whole lung volume was acquired at 1, 7, 21, and >70 days after the lungs were dried and served as validation for fixation stability. No significant shrinkage was observed: +8.95% change from in vivo to fixed lung ( P = 0.12), −1.47% change from day 1 to day 7 ( P = 0.07), −2.51% change from day 1 to day 21 ( P = 0.05), and −4.90% change from day 1 to day 70 and thereafter ( P = 0.04). μCT evaluation showed well-fixed alveoli and capillary beds correlating with histological analysis. A fixation and imaging method has been established for μCT imaging of the murine lung that allows for ex vivo morphometric analysis, representative of the in vivo lung.
Analytical Expressions for Frequency and Buckling of Large Amplitude Vibration of Multilayered Composite Beams
Authors: Jafari-Talookolaei R. A. , Kargarnovin M. H. , Ahmadian M. T. , Abedi M.
Published: August 2011

The aim of this paper is to present analytical and exact expressions for the frequency and buckling of large amplitude vibration of the symmetrical laminated composite beam (LCB) with simple and clamped end conditions. The equations of motion are derived by using Hamilton′s principle. The influences of axial force, Poisson effect, shear deformation, and rotary inertia are taken into account in the formulation. First, the geometric nonlinearity based on the von Karman′s assumptions is incorporated in the formulation while retaining the linear behavior for the material. Then, the displacement fields used for the analysis are coupled using the equilibrium equations of the composite beam. Substituting this coupled displacement fields in the potential and kinetic energies and using harmonic balance method, we obtain the ordinary differential equation in time domain. Finally, applying first order of homotopy analysis method (HAM), we get the closed form solutions for the natural frequency and deflection of the LCB. A detailed numerical study is carried out to highlight the influences of amplitude of vibration, shear deformation and rotary inertia, slenderness ratios, and layup in the case of laminates on the natural frequency and buckling load.
Proto-oncogene PBF/PTTG1IP Regulates Thyroid Cell Growth and Represses Radioiodide Treatment
Authors: Read Martin L. , Lewy Greg D. , Fong Jim C.W. , Sharma Neil , Seed Robert I. , Smith Vicki E. , Gentilin Erica , Warfield Adrian , Eggo Margaret C. , Knauf Jeffrey A. , Leadbeater Wendy E. , Watkinson John C. , Franklyn Jayne A. , Boelaert Kristien , McCabe Christopher J.
Published: August 2011

Pituitary tumor transforming gene (PTTG)-binding factor (PBF or PTTG1IP) is a little characterized proto-oncogene that has been implicated in the etiology of breast and thyroid tumors. In this study, we created a murine transgenic model to target PBF expression to the thyroid gland (PBF-Tg mice) and found that these mice exhibited normal thyroid function, but a striking enlargement of the thyroid gland associated with hyperplastic and macrofollicular lesions. Expression of the sodium iodide symporter (NIS), a gene essential to the radioiodine ablation of thyroid hyperplasia, neoplasia, and metastasis, was also potently inhibited in PBF-Tg mice. Critically, iodide uptake was repressed in primary thyroid cultures from PBF-Tg mice, which could be rescued by PBF depletion. PBF-Tg thyroids exhibited upregulation of Akt and the TSH receptor (TSHR), each known regulators of thyrocyte proliferation, along with upregulation of the downstream proliferative marker cyclin D1. We extended and confirmed findings from the mouse model by examining PBF expression in human multinodular goiters (MNG), a hyperproliferative thyroid disorder, where PBF and TSHR was strongly upregulated relative to normal thyroid tissue. Furthermore, we showed that depleting PBF in human primary thyrocytes was sufficient to increase radioiodine uptake. Together, our findings indicate that overexpression of PBF causes thyroid cell proliferation, macrofollicular lesions, and hyperplasia, as well as repression of the critical therapeutic route for radioiodide uptake. Cancer Res; 71(19); 6153–64. ©2011 AACR.
Wnt5a Suppresses Epithelial Ovarian Cancer by Promoting Cellular Senescence
Authors: Bitler Benjamin G. , Nicodemus Jasmine P. , Li Hua , Cai Qi , Wu Hong , Hua Xiang , Li Tianyu , Birrer Michael J. , Godwin Andrew K. , Cairns Paul , Zhang Rugang
Published: August 2011

Epithelial ovarian cancer (EOC) remains the most lethal gynecologic malignancy in the United States. Thus, there is an urgent need to develop novel therapeutics for this disease. Cellular senescence is an important tumor suppression mechanism that has recently been suggested as a novel mechanism to target for developing cancer therapeutics. Wnt5a is a noncanonical Wnt ligand that plays a context-dependent role in human cancers. Here, we investigate the role of Wnt5a in regulating senescence of EOC cells. We show that Wnt5a is expressed at significantly lower levels in human EOC cell lines and in primary human EOCs (n = 130) compared with either normal ovarian surface epithelium (n = 31; P = 0.039) or fallopian tube epithelium (n = 28; P < 0.001). Notably, a lower level of Wnt5a expression correlates with tumor stage (P = 0.003) and predicts shorter overall survival in EOC patients (P = 0.003). Significantly, restoration of Wnt5a expression inhibits the proliferation of human EOC cells both in vitro and in vivo in an orthotopic EOC mouse model. Mechanistically, Wnt5a antagonizes canonical Wnt/β-catenin signaling and induces cellular senescence by activating the histone repressor A/promyelocytic leukemia senescence pathway. In summary, we show that loss of Wnt5a predicts poor outcome in EOC patients and Wnt5a suppresses the growth of EOC cells by triggering cellular senescence. We suggest that strategies to drive senescence in EOC cells by reconstituting Wnt5a signaling may offer an effective new strategy for EOC therapy. Cancer Res; 71(19); 6184–94. ©2011 AACR.
ABT-898 Induces Tumor Regression and Prolongs Survival in a Mouse Model of Epithelial Ovarian Cancer
Authors: Campbell Nicole , Greenaway James , Henkin Jack , Petrik Jim
Published: August 2011

Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy and is often not diagnosed until late stages due to its asymptomatic nature. Women diagnosed with EOC typically undergo surgical debulking followed by chemotherapy; however, disease recurrence often occurs. In this study, we evaluated the ability of the thrombospondin-1 mimetic peptide, ABT-898, to regress established, late-stage tumors in a mouse model of human EOC. Ovarian tumors were induced and ABT-898 treatment was initiated at time points that were representative of late stages of the disease to study tumor regression. ABT-898 induced tumor regression and reduced the morbidity of treated animals compared with controls. Analysis of tumors from ABT-898–treated animals showed reduced abnormal tumor vasculature, decreased expression of the proangiogenic compound VEGF, and reduced tumor tissue hypoxia. ABT-898 treatment initiated at late-stage disease also significantly prolonged disease-free survival compared with control animals. Results from this study show that ABT-898 is capable of regressing established ovarian tumors in an animal model of the disease. As most women are detected at advanced stage EOC, ABT-898 may improve our treatment of ovarian cancer. Mol Cancer Ther; 10(10); 1876–85. ©2011 AACR.
p57Kip2 and Cancer: Time for a Critical Appraisal
Authors: Borriello Adriana , Caldarelli Ilaria , Bencivenga Debora , Criscuolo Maria , Cucciolla Valeria , Tramontano Annunziata , Oliva Adriana , Perrotta Silverio , Della Ragione Fulvio
Published: August 2011

p57Kip2 is a cyclin-dependent kinase inhibitor belonging to the Cip/Kip family, which also includes p21Cip1 and p27Kip1. So far, p57Kip2 is the least-studied Cip/Kip protein, and for a long time its relevance has been related mainly to its unique role in embryogenesis. Moreover, genetic and molecular studies on animal models and patients with Beckwith-Wiedemann syndrome have shown that alterations in CDKN1C (the p57Kip2 encoding gene) have functional relevance in the pathogenesis of this disease. Recently, a number of investigations have identified and characterized heretofore unexpected roles for p57Kip2. The protein appears to be critically involved in initial steps of cell and tissue differentiation, and particularly in neuronal development and erythropoiesis. Intriguingly, p27Kip1, the Cip/Kip member that is most homologous to p57Kip2, is primarily involved in the process of cell cycle exit. p57Kip2 also plays a critical role in controlling cytoskeletal organization and cell migration through its interaction with LIMK-1. Furthermore, p57Kip2 appears to modulate genome expression. Finally, accumulating evidence indicates that p57Kip2 protein is frequently downregulated in different types of human epithelial and nonepithelial cancers as a consequence of genetic and epigenetic events. In summary, the emerging picture is that several aspects of p57Kip2's functions are only poorly clarified. This review represents an appraisal of the data available on the p57Kip2 gene and protein structure, and its role in human physiology and pathology. We particularly focus our attention on p57Kip2 changes in cancers and pharmacological approaches for modulating p57Kip2 levels. Mol Cancer Res; 9(10); 1269–84. ©2011 AACR.
MicroRNA-21 Regulates Vascular Smooth Muscle Cell Function via Targeting Tropomyosin 1 in Arteriosclerosis Obliterans of Lower Extremities
Authors: Wang Mian , Li Wen , Chang Guang-Qi , Ye Cai-Sheng , Ou Jing-Song , Li Xiao-Xi , Liu Yong , Cheang Tuck-Yun , Huang Xue-Ling , Wang Shen-Ming
Published: August 2011

Objective

—The goal of this study was to determine the expression signature and the potential role of microRNAs in human arteries with arteriosclerosis obliterans (ASO).

Methods and Results

—The expression profiles of microRNAs in human arteries with ASO and in normal control arteries were determined by quantitative reverse transcription–polymerase chain reaction array. Among the 617 detected microRNAs, multiple microRNAs were aberrantly expressed in arteries with ASO. Some of these dysregulated microRNAs were further verified by quantitative reverse transcription–polymerase chain reaction. Among them, microRNA-21 (miR-21) was mainly located in arterial smooth muscle cells (ASMCs) and was increased by more than 7-fold in ASO that was related to hypoxia inducible factor 1-α. In cultured human ASMCs, cell proliferation and migration were significantly decreased by inhibition of miR-21. 3′-Untranslated region luciferase assay confirmed that tropomyosin 1 was a target of miR-21 that was involved in miR-21-mediated cellular effects, such as cell shape modulation.

Conclusion

—The results suggest that miR-21 is able to regulate ASMC function by targeting tropomyosin 1. The hypoxia inducible factor-1 α/miR-21/tropomyosin 1 pathway may play a critical role in the pathogenesis of ASO. These findings might provide a new therapeutic target for human ASO.
Smooth Muscle Calponin
Authors: Long Xiaochun , Slivano Orazio J. , Cowan Sarah L. , Georger Mary A. , Lee Ting-Hein , Miano Joseph M.
Published: August 2011

Objective—

Smooth muscle calponin (
CNN1
) contains multiple conserved intronic CArG elements that bind serum response factor and display enhancer activity in vitro. The objectives here were to evaluate these CArG elements for activity in transgenic mice and determine the effect of human CNN1 on injury-induced vascular remodeling.

Methods and Results—

Mice carrying a lacZ reporter under control of intronic CArG elements in the human
CNN1
gene failed to show smooth muscle cell (SMC)-restricted activity. However, deletion of the orthologous sequences in mice abolished endogenous
Cnn1
promoter activity, suggesting their necessity for in vivo
Cnn1
expression. Mice carrying a 38-kb bacterial artificial chromosome (BAC) harboring the human
CNN1
gene displayed SMC- restricted expression of the corresponding CNN1 protein, as measured by immunohistochemistry and Western blotting. Extensive BAC recombineering studies revealed the absolute necessity of a single intronic CArG element for correct SMC-restricted expression of human CNN1. Overexpressing human CNN1 suppressed neointimal formation following arterial injury. Mice with an identical BAC carrying mutations in CArG elements that inhibit human CNN1 expression showed outward remodeling and neointimal formation.

Conclusion—

A single intronic CArG element is necessary but insufficient for proper CNN1 expression in vivo. CNN1 overexpression antagonizes arterial injury-induced neointimal formation.
Cathepsin K Deficiency Reduces Elastase Perfusion–Induced Abdominal Aortic Aneurysms in Mice
Authors: Sun Jiusong , Sukhova Galina K. , Zhang Jie , Chen Han , Sjöberg Sara , Libby Peter , Xia Mingcan , Xiong Na , Gelb Bruce D. , Shi Guo-Ping
Published: August 2011

Objective—

Cathepsin K (CatK) is one of the most potent mammalian elastases. We have previously shown increased expression of CatK in human abdominal aortic aneurysm (AAA) lesions. Whether this protease participates directly in AAA formation, however, remains unknown.

Methods and Results—

Mouse experimental AAA was induced with aortic perfusion of a porcine pancreatic elastase. Using this experimental model, we demonstrated that absence of CatK prevented AAA formation in mice 14 days postperfusion. CatK deficiency significantly reduced lesion CD4
+
T-cell content, total lesion and medial cell proliferation and apoptosis, medial smooth muscle cell (SMC) loss, elastinolytic CatL and CatS expression, and elastin fragmentation, but it did not affect AAA lesion Mac-3
+
macrophage accumulation or CD31
+
microvessel numbers. In vitro studies revealed that CatK contributed importantly to CD4
+
T-cell proliferation, SMC apoptosis, and other cysteinyl cathepsin and matrix metalloproteinase expression and activities in SMCs and endothelial cells but played negligible roles in microvessel growth and monocyte migration. AAA lesions from CatK-deficient mice showed reduced elastinolytic cathepsin activities compared with those from wild-type control mice.

Conclusion—

This study demonstrates that CatK plays an essential role in AAA formation by promoting T-cell proliferation, vascular SMC apoptosis, and elastin degradation and by affecting vascular cell protease expression and activities.