bluuebunny/crossref_metadata_2025 huggingface dataset:
Decomposition along a bog to rich fen gradient in central Alberta, Canada
Authors: Szumigalski Anthony R. , Bayley Suzanne E.
Published: August 2010

The carbon (C) and nitrogen (N) contents and decomposition rates of the aboveground litter were measured in five peatlands (bog, poor fen, open moderately rich fen, wooded moderately rich fen, and lacustrine sedge fen) in central Alberta, Canada, over a period of 2 years. Decay rates and C and N content of the dominant species were measured at each site. Weight losses after 1 and 2 years were negatively correlated with initial and final C/N ratios. Weight losses were positively correlated with initial and final %N, with the fastest weight losses in the species with the highest N content. Rates of decay within sites differed according to litter types, with Carex > Betula > mosses. Decay rates and C and N content were also determined for a standard litter type (Carex lasiocarpa), to make cross-site comparisons. Standard litter weight losses differed between sites after 1 and 2 years of decay. The sites ranked poor fen > wooded–rich fen > bog > open–rich fen > sedge fen in order of greatest to smallest percent weight loss after 2 years. After 1 year, weight loss of the standard litter was negatively correlated with water level and pH-related parameters and positively correlated with total dissolved P. Decomposition was correlated with both substrate quality and environmental parameters, but the former may be more important than the latter in controlling decomposition in these peatlands. Keywords: decomposition, peatlands, carbon, nitrogen, hydrology, water chemistry.
Flooding, topography, and successional age as determinants of species diversity in old-field vegetation
Authors: Trebino Hernán J. , Chaneton Enrique J. , León Rolando J. C.
Published: August 2010

We studied the spatial pattern of plant richness and diversity along topographic gradients in two pairs of plots with 3 and 4 versus 9 and 10 years of abandonment from cultivation, in the Inland Pampa of Argentina. Vegetation in each plot was sampled for species cover every 10 m along a transect running parallel to the maximum local slope. Observations began after 2 years of unusually severe floods and continued for over 6 years. Community richness and diversity both increased with topographic height only the first year after flooding, in young and old successional plots. Richness and diversity decreased over time in upper and intermediate topographic positions, converging toward lesser values observed in lower positions. A transient peak in diversity occurred in lower topographic positions several years after flood disturbance. Species richness was similarly constrained by flooding stress and successional development. Thus, maximum diversity occurred at an early stage of succession in upper, infrequently flooded sites. Spatial and temporal patterns of plant diversity in this successional system did not generally conform with predictions from intermediate disturbance models. We propose that control of species diversity in old-field vegetation changed with time since flooding from physical stress to strong biotic interactions. Keywords: pampean grasslands, secondary succession, disturbance and stress gradients, species richness, vegetation structure.
Relationship between cortical resin acids and resistance of Sitka spruce to the white pine weevil
Authors: Tomlin Elizabeth S. , Borden John H. , Pierce Jr. Harold D.
Published: August 2010

Cortical resin acids were analyzed both quantitatively and qualitatively among 10 provenances and 11 genotypes of Sitka spruce, Picea sitchensis Bong (Carr.), putatively resistant to the white pine weevil, Pissodes strobi (Peck), and compared with susceptible trees. Trees in 5 of the 11 resistant genotypes had significantly greater amounts of cortical resin acid than susceptible trees. Of seven individual acids analyzed, pimaric, isopimaric, levopimaric, dehydroabietic, abietic, and neoabietic acid, but not palustric acid, were found in significantly greater amounts in trees from resistant than susceptible provenances. Eighteen percent of the variation in resin acid content could be accounted for by variation in the capacity of cortical resin ducts, indicating that the other 82% of variation is a result of differences in resin acid concentration in the resin. Trees with very high resin acid levels may have a greater capacity for resinosis than susceptible trees, may deter feeding, or may produce resin that is toxic to eggs and larvae. Canonical discriminant analysis revealed that several resistant clones, particularly two from the Kitwanga provenance, could be distinguished from others on the basis of their resin acid profiles. Because it separated trees on the basis of genotype, but not according to degree of resistance, canonical discriminant analysis may be more useful in "chemotyping" trees than in screening for resistance. Keywords: Picea, cortex, resin acids, Pissodes strobi, resistance.
Selection for independence of floral and vegetative traits: evidence from correlation patterns in five species
Authors: Conner Jeffrey K. , Sterling Andrea
Published: August 2010

Underlying developmental and genetic relationships cause positive correlations among the sizes of a variety of plant traits. Selection for functional independence among traits, however, can reduce these correlations over evolutionary time. In 1960, R.L. Berg hypothesized that the sizes of flowers in insect-pollinated plants should be selected to remain constant regardless of the size of vegetative structures, so that flowers match the sizes of their pollinators for effective pollination. This hypothesis of functional independence of floral sizes from the size of the rest of the plant predicts that correlations between floral and vegetative traits should be reduced relative to correlations within trait groups. We measured correlations in five species of insect-pollinated plants, including four Brassicaceae and Phlox divaricata. Our results support the hypothesis. The correlations among floral traits and the correlations among vegetative traits were significantly greater than the correlations across these two groups of traits in all five species. Keywords: phenotypic correlations, natural selection, functional independence, pollination, floral evolution.
Trace element geochemistry of Nova Scotia (Canada) maple syrup
Authors: Greenough John D. , Fryer Brian J. , Mallory-Greenough Leanne
Published: August 2010

Between 2000 and 2005, 50 sugar maple ( Acer saccharum Marshall, 1785) syrup samples from 16 producers in northern Nova Scotia, were analyzed (for 39 elements) using new techniques and inductively coupled plasma – mass spectrometry. Multidimensional scaling (exploratory statistics) using all samples and chemical data indicates that composition correlates with producer–woodlot, syrup colour (percent transmission), and processing (boiling alone versus reverse osmosis + boiling). Data are subdivided to explore these relationships. Using boiled samples (five producers, 21 samples), producers–woodlots are distinguished by high field-strength (Cr, Hf, and U), rare-earth (La, Pr, and Nd), chalcophile (Cu), alkaline earth (Ba, Ca), and especially alkali elements (Na, K, Rb, and Cs). On average, element concentrations are 1.6 times higher in darkest, boiled-only syrups (n = 6) compared with the lightest boiled syrups (same producers; n = 6). Apparently, dark syrups result from sap that contains low sugar content but similar element concentrations. More boiling to concentrate sugar causes caramelization, resulting in darker syrup and higher element concentrations. Averages for boiled and osmosis-processed syrups suggest that cations with small ionic radius and high charge (3+and 4+) are ∼1.6 times higher in boiled samples. These cations are partially lost by passing through the osmosis membrane. Based on boiled samples, water-soluble alkali metal cations with large ionic radius and low charge (+1) have high continental-crust-normalized concentrations (0.1 times), whereas insoluble cations with smaller ionic radius and higher charge (e.g., Hf, Th, REE) exhibit low (0.0001) concentrations. This pattern apparently reflects element solubility in soil water. Concentrations are ∼10 times those in Nova Scotia wine. Because ∼35 L of sap makes 1 L of syrup, the lower concentration factor in wine may reflect evapotranspiration concentration in grapes. Several elements in syrup (Sn, Cu, Pb, Zn), show producer-related concentration anomalies that probably reflect equipment (tanks, pumps, evaporators) used in processing.
ON THE HAMILTONIAN FORM OF THE EINSTEIN EQUATIONS FOR GRAVITATIONAL FIELD
Authors: FAYZULLAEV B. A.
Published: August 2010

It is shown that the Einstein gravitational equations and the canonical equations, which follow from the Dirac–Schwinger Hamiltonian, in the Faddeev variables coincide. To prove this, first, the Einstein equations are rewritten in canonical variables and then the time derivative of the generalized momenta of the gravitational field in Faddeev form are calculated using canonical Poisson brackets. The results coincide.
PSEUDOSPIN AND SPIN SYMMETRY FOR THE RING-SHAPED GENERALIZED HULTHÉN POTENTIAL
Authors: AYDOĞDU OKTAY , SEVER RAMAZAN
Published: August 2010

We obtain the bound state energy eigenvalues and the corresponding wave functions of the Dirac particle for the generalized Hulthén potential plus a ring-shaped potential with pseudospin and spin symmetry. The Nikiforov–Uvarov method is used in the calculations. Contribution of the angle-dependent part of the potential to the relativistic energy spectra are investigated. In addition, it is shown that the obtained results coincide with those available in the literature.
NEUTRINO MASSES AND μ TERMS IN A SUPERSYMMETRIC EXTRA U(1) MODEL
Authors: SUEMATSU DAIJIRO , TOMA TAKASHI , YOSHIDA TETSURO
Published: August 2010

We propose a supersymmetric extra U(1) model, which can generate small neutrino masses and necessary μ terms, simultaneously. Fields including quarks and leptons are embedded in three 27's of E6 in a different way among generations. The model has an extra U(1) gauge symmetry at TeV regions, which has discriminating features from other models studied previously. Since a neutrino mass matrix induced in the model has a constrained texture with limited parameters, it can give a prediction. If we impose neutrino oscillation data to fix those parameters, a value of sin θ13 can be determined. We also discuss several phenomenological features which are discriminated from the ones of the MSSM.
HAWKING RADIATION FROM KERR–NEWMAN BLACK HOLE AND TUNNELING MECHANISM
Authors: UMETSU KOICHIRO
Published: August 2010

We present the derivation of Hawking radiation by using the tunneling mechanism in a rotating and charged black hole background. We show that the four-dimensional Kerr–Newman metric, which has a spherically nonsymmetric geometry, becomes an effectively two-dimensional spherically symmetric metric by using the technique of the dimensional reduction near the horizon. We can thus readily apply the tunneling mechanism to the nonspherical Kerr and Kerr–Newman metric.
ONE-LOOP QUANTUM COSMOLOGICAL CORRECTION TO THE GRAVITATIONAL CONSTANT IN THE CLOSED FRIEDMANN–ROBERTSON–WALKER UNIVERSE
Authors: JALALZADEH S. , DARABI F.
Published: August 2010

In this paper, we calculate the one-loop quantum cosmological corrections to the kink energy in the closed Friedmann–Robertson–Walker universe in which the fluctuation potential V″ has a shape invariance property. We use the generalized zeta-function regularization method to implement our setup for describing quantum kink-like states. It is conjectured that the corrections lead to the renormalized gravitational constant.
UNDERSTANDING CONFINEMENT IN QCD: ELEMENTS OF A BIG PICTURE
Authors: SHIFMAN MIKHAIL
Published: August 2010

I give a brief review of advances in the strong interaction theory. This talk was delivered at the Conference in honor of Murray Gell-Mann's 80th birthday, 24–26 February 2010, Singapore.
PHASE SYNCHRONIZATION OF RÖSSLER OSCILLATORS WITH PARAMETRIC EXCITATION
Authors: LIU YONG , MA JUN
Published: August 2010

Phase synchronization of parametric excited Rössler system has been investigated in this paper. By introducing the conception of phase for a chaotic motion, it has been demonstrated that the mean frequency of chaotic attractor and the frequency of the parametric excitation may be locked in different ratios for certain parameter conditions, implying phase synchronization can be observed. The evolution from nonsynchronized state to phase synchronization has been discussed in detail, which reveals different phase dynamics may exist during the process. With the variation of parameters, the imaging point on the Poincaré plane may finally settle down onto the attractor, which yields phase synchronization.
STUDY ON MOMENTUM DENSITY IN SEMICONDUCTOR ALLOYS GeC and SnC BY POSITRON ANNIHILATION
Authors: AMRANE N.
Published: August 2010

The independent particle model (IPM) coupled with empirical pseudopotential method (EPM) was used to compute the thermalized positron charge densities in specific family of binary tetrahedrally coordinated crystals of formula ANB8-N . Initial results show a clear asymmetrical positron charge distribution relative to the bond center. It is observed that the positron density is maximum in the open interstices and is excluded not only from the ion cores but also to a considerable degree from the valence bonds. Electron-positron momentum densities are calculated for the (001, 110) planes. The results are used to analyze the positron effects in GeC and SnC . Our computational technique provides the theoretical means of interpreting the k-space densities obtained experimentally using the two-dimensional angular correlation of annihilation radiation (2D-ACAR).
ANALYTIC WAVE FUNCTIONS FOR THE HALF-FILLED LOWEST LANDAU LEVEL
Authors: CIFTJA ORION
Published: August 2010

We consider a two-dimensional strongly correlated electronic system in a strong perpendicular magnetic field at half-filling of the lowest Landau level (LLL). We seek to build a wave function that, by construction, lies entirely in the Hilbert space of the LLL. Quite generally, a wave function of this nature can be built as a linear combination of all possible Slater determinants formed by using the complete set of single-electron states that belong to the LLL. However, due to the vast number of Slater determinant states required to form such basis functions, the expansion is impractical for any but the smallest systems. Thus, in practice, the expansion must be truncated to a small number of Slater determinants. Among many possible LLL Slater determinant states, we note a particular special class of such wave functions in which electrons occupy either only even, or only odd angular momentum states. We focus on such a class of wave functions and obtain analytic expressions for various quantities of interest. Results seem to suggest that these special wave functions, while interesting and physically appealing, are unlikely to be a very good approximation for the exact ground state at half-filling factor. The overall quality of the description can be improved by including other additional LLL Slater determinant states. It is during this process that we identify another special family of suitable LLL Slater determinant states to be used in an enlarged expansion.
MICROSTRUCTURES AND ABRASIVE PROPERTIES OF THE OXIDE COATINGS ON Al6061 ALLOYS PREPARED BY PLASMA ELECTROLYTIC OXIDATION IN DIFFERENT ELECTROLYTES
Authors: WANG KAI , BYUN SANGSIK , LEE CHAN GYU , KOO BON HEUN , WANG YI QI , SONG JUNG IL
Published: August 2010

Al 2 O 3 coatings were prepared on T6-tempered Al6061 alloys substrate under a hybrid voltage (AC 200 V–60 Hz and DC 260 V value) by plasma electrolytic oxidation (PEO) in 30 min. The effects of different electrolytes on the abrasive behaviors of the coatings were studied by conducting dry ball-on-disk wear tests. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to investigate the coating microstructure. XRD analysis results show that the coatings mainly consist of α- and γ- Al 2 O 3, and some mullite and AlPO 4 phase in Na 2 SiO 3 and Na 3 PO 4 containing electrolytes, respectively. The wear test results show that the coatings which were PEO-treated in Na 3 PO 4 containing electrolyte presented the most excellent abrasive resistance property.
CHARACTERISTICS OF THIN FILMS SYNTHESIZED FROM NANO BOEHMITE AND ORGANOALKOXYSILANE
Authors: PARK HOYYUL , AHN MYEONGSANG , NA MOONKYONG
Published: August 2010

We investigated the properties of inorganic–organic hybrid thin films prepared by sol–gel reaction. Sol solutions were synthesized by using two kinds of nanosized boehmite and methyltrimethoxysilane (MTMS) in variation with the amount of MTMS at different reaction times. Boehmite nano sol of spherical and fibrous shapes was used as inorganic material, and MTMS was used as organic material. The morphology of boehmite nano sol powder was observed by transmission electron microscopy. Coating sols were prepared from boehmite sol and MTMS by sol–gel reaction. Physical and chemical properties of thin films prepared from boehmite and MTMS sols were investigated. Surface hydrophobicity, roughness, thickness, thermal resistance and electrical resistivity of boehmite/MTMS thin films were investigated.
HYDROGENATED AMORPHOUS/NANOCRYSTALLINE SILICON THIN FILMS ON POROUS ANODIC ALUMINA SUBSTRATE
Authors: KIM SANG-OK , KHODIN ALIAKSANDR , LEE JOONG KEE
Published: August 2010

Hydrogenated amorphous and nanocrystalline silicon thin films were grown on porous anodic alumina substrates using electron cyclotron resonance-chemical vapor deposition technique from argon, hydrogen and silane gas composition. The structural characterization of the deposited hydrogenated silicon films were performed by scanning electron microscopy, Raman spectroscopy, and X-ray diffraction studies. The results revealed that mixed amorphous/nanocrystalline silicon phases with specific novel morphology were obtained on textured surfaces. The evolution of the film on ripple-like surface exhibited amorphous dominant structure, however, the film deposited on tipped/ribbed surface consisted of amorphous and nanocrystalline phases composite. The growth process strongly depends on the textured substrate pattern, which influences on the nanostructure shapes and crystallinity.
MICROSTRUCTURAL ANALYSIS OF CORE-SHELL STRUCTURED MgB2 SUPERCONDUCTING FIBERS FABRICATED BY HYBRID PHYSICAL CHEMICAL VAPOR DEPOSITION
Authors: KANG SEONG GU , PARK SUNG CHANG , CHUNG JUN-KI , LEE NAM HOON , KANG WON NAM , SONG KYU JEONG , LEE TAE-KEUN , KIM CHEOL JIN
Published: August 2010

We have deposited MgB 2 thin films on the carbon fiber by hybrid physical–chemical vapor deposition (HPCVD) method which is known as the most effective technique for depositing MgB 2 thin films without pore formation. By adopting carbon fiber as substrate and gas phase reaction between diborane ( B 2 H 6) gas and Mg vapor for MgB 2 formation, core-shell structured MgB 2/ C composite fiber could be synthesized. The high quality of the prepared MgB 2 fibers was confirmed with scanning electron microscopy (SEM), and the critical temperature (T c ) of the sample deposited at 590°C and 12 sccm flow rate of B 2 H 6 was measured at ~40 K. The microstructures of MgB 2 layer was characterized using transmission electron microscopy (TEM). The bright-field TEM images showed MgB 2 with the grain size of several nanometers. The MgB 2 thin film showed highly dense microstructure without pore and well-connected to the carbon fiber interface. High-resolution TEM (HRTEM) images and scanning transmission electron microscopy (STEM) revealed the presence of interface phase between MgB 2 thin films and carbon fiber.
COATING LAYER AND CORROSION PROTECTION CHARACTERISTICS IN SEA WATER WITH VARIOUS THERMAL SPRAY COATING MATERIALS FOR STS304
Authors: KIM SEONG-JONG , WOO YONG-BIN
Published: August 2010

We investigated the optimal method of application and the anticorrosive abilities of Zn , Al , and Zn + 15%Al spray coatings in protecting stainless steel 304 (STS304) in sea water. If a defect such as porosity or an oxide layer, causes STS304 to be exposed to sea water, and the thermal spray coating material will act as the cathode and anode, respectively. The Tafel experiments revealed that Al -coated specimens among applied coating methods had the lowest corrosion current densities. As the corrosion potential decreases with increasing corrosion current density, we estimated the characteristics and lifetime of the protective thermal spray coating layer in the galvanic cell formed by the thermal spray coating layer and STS304.
PROPERTIES OF COPPER LAYER ON Si(100) FROM Cu(dmamb)2
Authors: JIN SEONG-EON , LEE DOHAN , LEE SEUNGMOO , CHOI JONG-MUN , KIM BUMJOON , KIM CHANG GYOUN , CHUNG TACK-MO , BYUN DONG-JIN
Published: August 2010

Cu seed layer was deposited by chemical vapor deposition using new Cu precursor, Cu(dmamb) 2. The Cu layers still need the barrier layer to prevent the diffusion, so Ta and Ti were used for the barrier layer on Si(100) . Low temperature (LT) copper buffer layer was introduced and the effect of the buffer on the Cu films was investigated. The grown Cu layers were analyzed using FESEM, XRD, and four point probe measurement. The Cu seed layers were successfully deposited using Cu(dmamb) 2 precursor. Better thickness uniformity was obtained in the Cu films with the LT Cu buffer, which lowered the electrical resistivity.
THERMOELECTRIC CHARACTERISTICS OF THE THERMOPILE SENSORS PROCESSED WITH THE ELECTRODEPOSITED Bi–Te AND Sb–Te THIN FILMS
Authors: KIM MIN-YOUNG , OH TAE-SUNG
Published: August 2010

A thermopile sensor composed of 196 pairs of p–n thin film legs was processed on a glass substrate by using successive electrodeposition of the n-type Bi–Te and the p-type Sb–Te thin films. The 5.3-μm thick Bi–Te film, electrodeposited at a constant voltage of -50 mV in the 50-mM electrolyte with the Bi/(Bi + Te) mole ratio of 0.5, exhibited a Seebeck coefficient of -67 μV/K. The 5.2-μm thick Sb–Te film, electrodeposited at a constant voltage of 20 mV in the 70-mM solution with the Sb/(Sb + Te) mole ratio of 0.9, possessed a Seebeck coefficient of 63 μV/K. The thermopile sensor exhibited the sensitivities of 13.1 mV/K with temperature differences smaller than 9 K and of 27.3 mV/K with temperature differences larger than 9 K respectively, across the hot and cold ends.
IN SITU EXAMINATIONS OF MECHANICAL DICING-INDUCED DAMAGE IN SEMICONDUCTOR WAFERS
Authors: LEE SEONG-MIN
Published: August 2010

This work illustrates how the separation of a semiconductor wafer into individual devices occurs during conventional mechanical dicing. In situ examinations indicate that the final separation of the wafer takes place before the dicing blade has fully penetrated its active surface. Thus, it was predicted that mechanical dicing-induced damage in the separated device patterns would be due to other mechanical actions rather than the grinding action between the diamond particles embedded in the blade and the wafer. Based on the in situ examinations, it was experimentally tested how manipulating the revolving speed of the dicing blade affected the prevention of dicing-induced damage to device patterns. The experimental results show that among various mechanical actions, the impact stress due to the revolving action of the blade could be the most possible candidate for damage in the device pattern on the final uncut semiconductor wafer.
EFFECT OF GRINDING-INDUCED SCRATCH GEOMETRY ON FRACTURE STRENGTH OF PLASTIC-ENCAPSULATED SEMICONDUCTOR DEVICES
Authors: LEE SEONG-MIN
Published: August 2010

The fracture strength of LOC (lead-on-chip) packages was measured through three-point bending tests. Metallurgical examination shows that failure in an LOC package begins at a pre-existing flaw in the form of a scratch on the bottom surface of the plastic-encapsulated silicon chip. The flexural strength of LOC packages was estimated as a function of the geometry of the grinding-induced scratches on the back surface of the chips. The major conclusion is that the fracture strength of the plastic package, including the silicon chip, can be enhanced up to 80% by changing its scratch marks from 0°, running parallel to its lateral direction, to 90°, running parallel to its longitudinal direction.
MICROSTRUCTURAL EVOLUTION AND RESIDUAL STRESSES OF AIR-PLASMA SPRAYED THERMAL BARRIER COATINGS UNDER THERMAL EXPOSURE
Authors: KWON JAE-YOUNG , KIM JAE-HYOUN , LEE SANG-YEOP , JUNG YEON-GIL , CHO HYUN , YI DONG-KEE , PAIK UNGYU
Published: August 2010

Microstructural evolution and fracture behavior of zirconia ( ZrO2 )-based thermal barrier coatings (TBCs) were investigated under thermal exposure. New ZrO 2 granule with 8 wt.% yttria ( Y2O3 ) with a deformed hollow morphology was developed through a spray drying process and employed to prepare TBCs. The thermal exposure tests were conducted at 1210°C with a dwell time of 100 h till 800 h. The residual stress at the interface between top coat and thermally grown oxide (TGO) layer was measured using a nanoindentation technique before and after thermal exposure. Vertical cracks on the top coat were newly formed and interlamellar cracks at the interface were enhanced after the thermal exposure of 800 h. Especially, partial delamination was observed at the interface after the thermal exposure of 800 h in TBC samples tested. The microstructural evolution in the top coat could be defined through load–displacement curves, showing a higher load or a less displacement after the thermal exposure of 800 h. The stress state was strongly dependent on the TGO geometry, resulting in the compressive stresses at the "valleys" or the "troughs," and the tensile stresses at the "crests" or peak areas, in the ranges of -500 to -75 MPa and of +168 to + 24 MPa, respectively. These stress terms incorporated with resintering during thermal exposure affected the mechanical properties such as hardness and elastic modulus of the top coat.
FABRICATION OF BRANCHED NANOTUBES OF SODIUM NIOBATE
Authors: LIU FEI , XUE DONGFENG
Published: August 2010

Novel three-dimensional (3D) branched nanotubes of sodium niobate ( NaNbO 3) were produced by a multi-step reaction, which involves the synthesis of Nb 2 O 5 branched nanowires and subsequently treating these precursors in alkali solution. XRD and SEM have been used to analyze current products. All the obtained nanobranches exhibited tubular structure, which was induced by nanoscale Kirkendall effect and surface diffusion. This work demonstrates a simple and efficient pathway to design hierarchical and complex hollow nanostructures, which are expected to have important applications, such as sensors and photocatalysts.
NiFe/INSULATOR/Cu COMPOSITE WIRES AND THEIR GIANT MAGNETO-IMPEDANCE EFFECTS
Authors: NING N. , FAN J. , WU J. , CHIRIAC H. , LI X. P.
Published: August 2010

In this work, two types of electrodeposited Ni–Fe /insulator/ Cu composite wires, namely Ni–Fe /seed layer/glass coated copper wire (Composite Wire A), and Ni–Fe /seed layer/sputtered SiO2/Cu (Composite Wire B), have been fabricated and their giant magneto-impedance effects have been investigated. With different implementations of the insulator layer, the magneto-impedance effect of Composite Wire A, whose insulator layer is cast from the melt Pyrex, is significantly higher than that of Composite Wire B with an insulator of sputtered SiO 2 layer. The profile of the insulator layer, as well as the thickness of magnetic layer and the diameter of the conductive core, greatly influences the interaction between the magnetic layer of Ni–Fe and the copper core, as shown in their giant magneto-impedance (GMI) effects. The maximum MI ratios obtained from Composite Wires A and B are 226% at 800 kHz when H ext = 0.87 Oe , and 95% at 1 MHz when H ext = 0 Oe , respectively. The Composite Wire A is a promising candidate for the sensing element of high sensitivity sensors to very weak magnetic field. For Composite Wire B, further improvement on its GMI effect and sensing performance requires optimization of its geometric parameters and the deposition conditions.
PREPARATION AND CHARACTERIZATION OF SUPER-HYDROPHOBIC SURFACES ON ALUMINUM AND STAINLESS STEEL SUBSTRATES
Authors: YU ZHIJIA , YU YUEFEI , LI YANFENG , SONG SHANPENG , HUO SUBIN , HAN XIUYAN
Published: August 2010

Hierarchical alveolate structures in nano- to microscale were fabricated on both aluminum and stainless steel substrates via a chemical etching. On aluminum surfaces, sharp edged caves and plateaus were found. On stainless steel substrate, fine papillae stand on protuberances. These surfaces exhibit super-hydrophobic properties after the fluorination treatment, their water contact angles are 158° and 160°, respectively, with the contact angle hysteresis of about 5°. The roll off angle is about 5°. Ice melting behaviors on a plate of aluminum super-hydrophobic surface were compared with those on a hydrophilic one, their difference shows that the new feature of super-hydrophobic surface could be expected.
An APPL1-AMPK signaling axis mediates beneficial metabolic effects of adiponectin in the heart
Authors: Fang Xiangping , Palanivel Rengasamy , Cresser Justin , Schram Kristin , Ganguly Riya , Thong Farah S. L. , Tuinei Joseph , Xu Aimin , Abel E. Dale , Sweeney Gary
Published: August 2010

Adiponectin promotes cardioprotection by various mechanisms, and this study used primary cardiomyocytes and the isolated working perfused heart to investigate cardiometabolic effects. We show in adult cardiomyocytes that adiponectin increased CD36 translocation and fatty acid uptake as well as insulin-stimulated glucose transport and Akt phosphorylation. Coimmunoprecipitation showed that adiponectin enhanced association of AdipoR1 with APPL1, subsequent binding of APPL1 with AMPKα2, which led to phosphorylation and inhibition of ACC and increased fatty acid oxidation. Using siRNA to effectively knockdown APPL1 in neonatal cardiomyocytes, we demonstrated an essential role for APPL1 in mediating increased fatty acid uptake and oxidation by adiponectin. Importantly, enhanced fatty acid oxidation in conjunction with AMPK and ACC phosphorylation was also observed in the isolated working heart. Despite increasing fatty acid oxidation and myocardial oxygen consumption, adiponectin increased hydraulic work and maintained cardiac efficiency. In summary, the present study documents several beneficial metabolic effects mediated by adiponectin in the heart and provides novel insight into the mechanisms behind these effects, in particular the importance of APPL1.
Diaphragm muscle shortening modulates kinematics of lower rib cage in dogs
Authors: Chu Iris , Fernandez Cristina , Rodowicz Kathleen Allen , Lopez Michael A. , Lu Raymond , Hubmayr Rolf D. , Boriek Aladin M.
Published: August 2010

We tested the hypothesis that diaphragm muscle shortening modulates volume displacement and kinematics of the lower rib cage in dogs and that posture and mode of ventilation affect such modulation. Radiopaque markers were surgically attached to the lower three ribs of the rib cage and to the midcostal region of the diaphragm in six dogs of ∼8 kg body masses, and the locations of these markers were determined by a biplane fluoroscopy system. Three-dimensional software modeling techniques were used to compute volume displacement and surface area of the midcostal diaphragm and the lower three ribs during quiet spontaneous breathing, mechanical ventilation, and bilateral phrenic nerve stimulation at different lung volumes spanning the vital capacity. Volume displaced by the diaphragm relative to that displaced by the lower ribs is disproportionately greater under mechanical ventilation than during spontaneous breathing in the supine position ( P < 0.05). At maximal stimulation, diaphragm volume displacement grows disproportionately larger than rib volume displacement as lung volume increases ( P < 0.05). Surface area of both the diaphragm and the lower ribs during maximal stimulation of the diaphragm is reduced compared with that at spontaneous breathing ( P < 0.05). In the prone posture, mechanical ventilation results in a smaller change in diaphragm surface area than spontaneous breathing ( P < 0.05). Our data demonstrate that during inspiration the lower rib cage moves not only through the pump- and bucket-handle motion, but also rotates around the spine. Taken together, these data support the observation that the kinematics of the lower rib cage and its mechanical interaction with the diaphragm are more complex than previously known.
The Field Emission Properties of Graphene Aggregates Films Deposited on Fe‐Cr‐Ni alloy Substrates
Authors: Lu Zhanling , Wang Wanjie , Ma Xiaotian , Yao Ning , Zhang Lan , Zhang Binglin
Published: August 2010

The graphene aggregates films were fabricated directly on Fe‐Cr‐Ni alloy substrates by microwave plasma chemical vapor deposition system (MPCVD). The source gas was a mixture of H2 and CH4 with flow rates of 100 sccm and 12 sccm, respectively. The micro‐ and nanostructures of the samples were characterized by Raman scattering spectroscopy, field emission scanning electron microscopy (SEM), and transparent electron microscopy (TEM). The field emission properties of the films were measured using a diode structure in a vacuum chamber. The turn‐on field was about 1.0 V/μm. The current density of 2.1 mA/cm2 at electric field of 2.4 V/μm was obtained.
The Theory of Reich's Fixed Point Theorem for Multivalued Operators
Authors: Lazăr Tania , Moţ Ghiocel , Petruşel Gabriela , Szentesi Silviu
Published: August 2010

The purpose of this paper is to present a theory of Reich's fixed point theorem for multivalued operators in terms of fixed points, strict fixed points, multivalued weakly Picard operators, multivalued Picard operators, data dependence of the fixed point set, sequence of multivalued operators and fixed points, Ulam-Hyers stability of a multivalued fixed point equation, well-posedness of the fixed point problem, and the generated fractal operator.
Forced Oscillation of Second‐Order Half‐Linear Dynamic Equations on Time Scales
Authors: Lin Quanwen , Jia Baoguo , Wang Qiru
Published: August 2010

We will establish a new interval oscillation criterion for second‐order half‐linear dynamic equation (r(t)[xΔ(t)] α) Δ + p(t)xα(σ(t)) = f(t) on a time scale 𝕋 which is unbounded, which is a extension of the oscillation result for second order linear dynamic equation established by Erbe et al. (2008). As an application, we obtain a sufficient condition of oscillation of the second‐order half‐linear differential equation ([x′(t)] α) ′ + csintxα(t) = cos t, where α = p/q, p, q are odd positive integers.
Registry Evaluation of Digital Ulcers in Systemic Sclerosis
Authors: Galluccio Felice , Matucci-Cerinic Marco
Published: August 2010

Digital ulcers are a very frequent complication of systemic sclerosis affecting about half of the SSc patients, and about 75% of the affected patients have their first DU episode within 5 years from their first non-Raynaud symptom. The lack of adequate classification criteria as well as the lack of knowledge of the development of DU have contributed to the opening of specific registries to better understand the natural history of these lesions. For these reason, specific disease registries play a fundamental role in this field of research. Thanks to the systematic collection of data and their subsequent analysis and comparison between different cohorts, it is possible to improve understanding of the underlying trigger mechanisms of DU development and to determine temporal trends. In the future, the development of recommendations for the management of DU remains of pivotal importance to prevent DU development and obtain rapid healing as well as reduction of pain and disability.
Primordial Non‐Gaussianities from Inflation Models
Authors: Chen Xingang
Published: August 2010

This is a pedagogical review on primordial non‐Gaussianities from inflation models. We introduce formalisms and techniques that are used to compute such quantities. We review different mechanisms which can generate observable large non‐Gaussianities during inflation, and distinctive signatures they leave on the non‐Gaussian profiles. They are potentially powerful probes to the dynamics of inflation. We also provide a nontechnical and qualitative summary of the main results and underlying physics.
Endocrine Disruptors and Leydig Cell Function
Authors: Svechnikov K. , Izzo G. , Landreh L. , Weisser J. , Söder O.
Published: August 2010

During the past decades, a large body of information concerning the effects of endocrine disrupting compounds (EDCs) on animals and humans has been accumulated. EDCs are of synthetic or natural origin and certain groups are known to disrupt the action of androgens and to impair the development of the male reproductive tract and external genitalia. The present overview describes the effects of the different classes of EDCs, such as pesticides, phthalates, dioxins, and phytoestrogens, including newly synthesized resveratrol analogs on steroidogenesis in Leydig cells. The potential impact of these compounds on androgen production by Leydig cells during fetal development and in the adult age is discussed. In addition, the possible role of EDCs in connection with the increasing frequency of abnormalities in reproductive development in animals and humans is discussed.
Caffeine's Vascular Mechanisms of Action
Authors: Echeverri Darío , Montes Félix R. , Cabrera Mariana , Galán Angélica , Prieto Angélica
Published: August 2010

Caffeine is the most widely consumed stimulating substance in the world. It is found in coffee, tea, soft drinks, chocolate, and many medications. Caffeine is a xanthine with various effects and mechanisms of action in vascular tissue. In endothelial cells, it increases intracellular calcium stimulating the production of nitric oxide through the expression of the endothelial nitric oxide synthase enzyme. Nitric oxide is diffused to the vascular smooth muscle cell to produce vasodilation. In vascular smooth muscle cells its effect is predominantly a competitive inhibition of phosphodiesterase, producing an accumulation of cAMP and vasodilation. In addition, it blocks the adenosine receptors present in the vascular tissue to produce vasoconstriction. In this paper the main mechanisms of action of caffeine on the vascular tissue are described, in which it is shown that caffeine has some cardiovascular properties and effects which could be considered beneficial.
Lipid Mediators in Acne
Authors: Ottaviani Monica , Camera Emanuela , Picardo Mauro
Published: August 2010

Multiple factors are involved in acne pathogenesis, and sebum secretion is one of the main ones. The role sebum plays in acne development has not been completely elucidated yet; however, increasing amounts of data seem to confirm the presence of alterations in sebum from acne patients. Altered ratio between saturated and unsaturated fatty acids has been indicated as an important feature to be considered in addition to the altered amount of specific fatty acids such as linoleic acid. Furthermore, particular attention has been focused on squalene peroxide that seems to be able to induce an inflammatory response beyond cytotoxicity and comedones formation. Moreover, recent data suggest that lipid mediators are able to interfere with sebocytes differentiation and sebogenesis through the activation of pathways related to peroxisome proliferators-activated receptors. Understanding the factors and mechanisms that regulate sebum production is needed in order to identify novel therapeutic strategies for acne treatment.
Nanocomposite Materials of Alternately Stacked C60 Monolayer and Graphene
Authors: Ishikawa Makoto , Kamiya Shu , Yoshimoto Shoji , Suzuki Masaru , Kuwahara Daisuke , Sasaki Naruo , Miura Kouji
Published: August 2010

We synthesized the novel nanocomposite consisting alternately of a stacked single graphene sheet and a C60 monolayer by using the graphite intercalation technique in which alkylamine molecules help intercalate large C60 molecules into the graphite. Moreover, it is found that the intercalated C60 molecules can rotate in between single graphene sheets by using  13C NMR measurements. This preparation method provides a general way for intercalating huge fullerene molecules into graphite, which will lead to promising materials with novel mechanical, physical, and electrical properties.
Effect of the Dispersibility of Nano-CuO Catalyst on Heat Releasing of AP/HTPB Propellant
Authors: Yang Yi , Yu Xinjie , Wang Jun , Wang Yaxue
Published: August 2010

Kneading time is adjusted to change the dispersibility of nano-CuO in AP/HTPB (Ammonia Perchlorate/Hydroxyl-Terminated Polybutadiene) composite propellants. Nano-CuO/AP is prepared to serve as the other dispersing method of nano-CuO, named predispersing procedure. Several kinds of heat releasing, thermal decomposition by DSC, combustion heat in oxygen environment, and explosion heat in nitrogen environment, are characterized to learn the effect of dispersibility of nano-CuO catalyst on heat releasing of propellants. With pre-dispersing procedures, thermal decomposition temperature of nano-CuO/AP and its propellant are about C and C lower than that of AP simple mixed with nano-CuO and its propellant, respectively. Comparing propellant with simple mixed nano-CuO kneading 3 hours, combustion heat and explosion heat of propellant with nano-CuO/AP increase about 1.4% and 1.7%, respectively. However, because of the breaking of nano-CuO/AP structure during kneading procedure, combustion heat and explosion heat of all the samples are decreased with the increase of kneading time after 3 hours.
Switching to Aripiprazole as a Strategy for Weight Reduction: A Meta-Analysis in Patients Suffering from Schizophrenia
Authors: Barak Yoram , Aizenberg Dov
Published: August 2010

Weight gain is one of the major drawbacks associated with the pharmacological treatment of schizophrenia. Existing strategies for the prevention and treatment of obesity amongst these patients are disappointing. Switching the current antipsychotic to another that may favorably affect weight is not yet fully established in the psychiatric literature. This meta-analysis focused on switching to aripiprazole as it has a pharmacological and clinical profile that may result in an improved weight control. Nine publications from seven countries worldwide were analyzed. These encompassed 784 schizophrenia and schizoaffective patients, 473 (60%) men and 311 (40%) women, mean age years. The major significant finding was a mean weight reduction by  kgs following the switch to aripiprazole (). Switching to an antipsychotic with a lower propensity to induce weight gain needs be explored as a strategy. Our analysis suggests aripiprazole as a candidate for such a treatment strategy.
Secreted and Membrane-Bound Isoforms of Protease ADAM9 Have Opposing Effects on Breast Cancer Cell Migration
Authors: Fry Jessica L. , Toker Alex
Published: August 2010

Tumor cell migration is mediated by cell-autonomous signaling mechanisms as well as paracrine and autocrine factors secreted by activated stromal cells in the tumor microenvironment. Like other members of the ADAM (a disintegrin and metalloproteinase) family, the integrin-binding metalloproteinase ADAM9 modulates cell-cell and cell-matrix interactions as well as ectodomain shedding of cell surface receptors and ligands, thereby modifying intracellular and extracellular signaling. ADAM9 transcripts are alternatively spliced to express a transmembrane protein (ADAM9-L) and a secreted variant (ADAM9-S). In this study, we show that ADAM9-S promotes breast cancer cell migration in a manner requiring its metalloproteinase activity, whereas ADAM9-L suppresses cell migration independent of its metalloproteinase activity. Suppression of migration by ADAM9-L requires a functional disintegrin domain and integrin binding. Expression analysis revealed that both ADAM9 isoforms are expressed in breast cancer cell lines and tissues. Therefore, relative levels of membrane-tethered and secreted variants of ADAM9 are a key determinant in manifestation of aggressive migratory phenotypes associated with breast cancer progression. Cancer Res; 70(20); 8187–98. ©2010 AACR.
Matrix Metalloproteinase-9 Regulates Tumor Cell Invasion through Cleavage of Protease Nexin-1
Authors: Xu Danmei , McKee Chad M. , Cao Yunhong , Ding Yunchuan , Kessler Benedikt M. , Muschel Ruth J.
Published: August 2010

Matrix metalloproteinase-9 (MMP-9) expression is known to enhance the invasion and metastasis of tumor cells. In previous work based on a proteomic screen, we identified the serpin protease nexin-1 (PN-1) as a potential target of MMP-9. Here, we show that PN-1 is a substrate for MMP-9 and establish a link between PN-1 degradation by MMP-9 and regulation of invasion. PN-1 levels increased in prostate carcinoma cells after downregulation of MMP-9 and in tissues of MMP-9–deficient mice, consistent with PN-1 degradation by MMP-9. We identified three MMP-9 cleavage sites in PN-1 and showed that mutations in those sites made PN-1 more resistant to MMP-9. Urokinase plasminogen activator (uPA) is inhibited by PN-1. MMP-9 augmented uPA activity in the medium of PC3-ML cells by degrading PN-1. Prostate cancer cells, overexpressing PN-1 or treated with MMP-9 shRNA, had reduced cell invasion in Matrigel. PN-1 siRNA restored uPA activity and the invasive capacity. PN-1 mutated in the serpin inhibitory domain, the reactive center loop, failed to inhibit uPA and to reduce Matrigel invasion. This study shows a novel molecular pathway in which MMP-9 regulates uPA activity and tumor cell invasion through cleavage of PN-1. Cancer Res; 70(17); 6988–98. ©2010 AACR.
DNA Methylation Analysis Determines the High Frequency of Genic Hypomethylation and Low Frequency of Hypermethylation Events in Plasma Cell Tumors
Authors: Salhia Bodour , Baker Angela , Ahmann Gregory , Auclair Daniel , Fonseca Rafael , Carpten John
Published: August 2010

Multiple myeloma (MM) is a plasma cell malignancy of the bone marrow, which evolves from a premalignant stage called monoclonal gammopathy of undetermined significance (MGUS). In some patients, an intermediate stage referred to as smoldering multiple myeloma (SMM) is clinically recognized, with the full-bore malignancy termed MM. We conducted a study to assess differential CpG methylation at 1,500 genic loci during MM progression and profiled CD138+ plasma cells from MGUS, SMM, and MM specimens; human myeloma cell lines; and normal plasma cell (NPC) samples. We showed that the number of differentially methylated loci (DML) increased with tumor grade, and the vast majority were due to hypomethylation. Hierarchical clustering analysis revealed samples that coclustered tightly with NPC. These cases, referred to as “normal-like,” contained significantly fewer DML when compared with their non–normal-like counterparts and displayed overall methylation levels resembling NPC. This study represents one of the first methylome interrogation studies in MM and points toward global hypomethylation at genic CpG loci as an important and early mechanism driving myelomagenesis. Determining the set of critical genes and pathways based on the myeloma methylome is expected to lead to an improved understanding of biological mechanisms involved in myelomagenesis. Cancer Res; 70(17); 6934–44. ©2010 AACR.