bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of fracture resistance in simulated immature teeth using resilon and ribbond as root reinforcements – An in vitro study
Authors: Hemalatha Hiremath , Sandeep Metgud , Kulkarni Sadanand , Yakub Shoeb Sheikh
Published: June 2009

Abstract –  Background/Aim:  To compare the reinforcement and strengthening ability of resilon, gutta‐percha, and ribbond in endodontically treated roots of immature teeth.

Material and Methods:  Sixty five freshly extracted human maxillary anterior teeth were prepared with a Peeso no. 6 to simulate immature teeth (Cvek’s stage 3 root development). After instrumentation, each root was irrigated with sodium hypochlorite and with ethylene diamino tetra acetic acid to remove the smear layer. To simulate single visit apexification technique a 4–5 mm white Pro Root mineral trioxide aggregate plug was placed apically using schilder carrier. The teeth were divided into three experimental groups and one control group. Group I – control group (root canals instrumented but not filled); Group II – backfilled with thermoplastisized gutta‐percha using AH plus sealer; Group III – reinforced with Resilon using epiphany sealer; Group IV – reinforced with Ribbond fibers using Panavia F luting cement. A Universal Testing Machine was used to apply a load, at the level of the lingual cementoenamel junction with a chisel‐shaped tip The peak load to fracture was recorded and statistical analysis was completed using student’s t‐test.

Results:  Values of peak load to fracture were 1320.8, 1604.88, 1620, and 1851newtons for Group I to Group IV respectively. The results of student’s t‐test, revealed no significant difference (P > 0.05,) between Group II and Group III. Comparison between Group IV and Group III and between Group IV and Group II revealed highly significant difference (P > 0.001).

Conclusions:  Teeth reinforced with Ribbond fibers using Panavia F luting cement showed the highest resistance to fracture. Resilon could not strengthen the roots and showed no statistically significant difference when compared with thermopasticised gutta‐percha in reinforcing immature tooth when tested with universal testing machine in an experimental model of immature tooth.
siRNA‐mediated gene silencing in the salivary gland using in vivo microbubble‐enhanced sonoporation
Authors: Sakai T , Kawaguchi M , Kosuge Y
Published: June 2009

Objectives:  siRNA‐induced gene silencing in the salivary gland using microbubble‐enhanced sonoporation was used to develop an in vivo gene knockdown technique.

Methods:  siRNA targeting rat glyceraldehyde‐3‐phosphate dehydrogenas (GAPDH) was mixed with echo‐enhanced microbubbles and reverse‐injected into rat parotid glands using transdermal ultrasound. To compare direct and transdermal ultrasound efficiencies, an incision was made on the lateral neck to expose the parotid glands for direct application. The efficiency of gene suppression was determined using quantitative reverse transcription‐polymerase chain reaction 24–72 h after siRNA delivery. Cytotoxicity was assessed using histological analysis.

Results:  Expression of rat GAPDH in the parotid glands was silenced 48 h after siRNA was delivered by ultrasound (frequency: 1 MHz; intensity: 2 W cm−2; exposure time: 2 min). High‐intensity ultrasound induced tissue damage and apoptotic change. Echo‐enhanced microbubbles significantly improved siRNA‐induced gene silencing by 10–50%. Compared with transdermal application, direct‐exposure ultrasound was only slightly effective, and no significant difference in gene expression was observed.

Conclusion:  The results indicate that microbubble‐enhanced sonoporation can yield in vivo siRNA gene silencing in the rat parotid gland. This technique could be applied to provide gene knockdown organs for functional genomic analyses and to develop siRNA‐based gene therapy.
Cytokines in Sjögren’s syndrome
Authors: Roescher N , Tak PP , Illei GG
Published: June 2009

Cytokines play a central role in the regulation of immunity and are often found to be deregulated in autoimmune diseases. Sjögren’s syndrome is a chronic autoimmune disease characterized by inflammation and loss of secretory function of the salivary and lachrymal glands. This review highlights the current knowledge of the expression and the function of pro‐ and anti‐inflammatory cytokines both locally and systemically in Sjögren’s syndrome patients. In the salivary glands, saliva and serum of these patients, many pro‐inflammatory cytokines are upregulated. Concomitantly, most anti‐inflammatory cytokines are not detectable or are expressed at low levels. Besides a role in inflammation, cytokines are also thought to be involved in salivary gland dysfunction by directly interfering with the epithelial cells in the glands. Future research on the role of novel cytokines in Sjögren’s syndrome in combination with a better understanding of the effect of cytokines on exocrine dysfunction will aide the identification of the best therapeutic targets for Sjögren’s syndrome.
COMPOSITION AND PASTING PROPERTIES OF STARCH FROM TWO COCOYAM CULTIVARS
Authors: MEPBA HORSFALL. D. , EBOH LUCY , EKO CHRISTIANAH B. , UKPABI UKPABI J.
Published: June 2009

The composition and pasting properties of starches from two cocoyam cultivars were evaluated and compared with cassava starch. The starch, amylose and amylopectin contents of Xanthosoma and Colocasia cultivars ranged from 79.2 to 79.8%, 23.3–23.6%, 56.1–56.2% and 77.6–77.8%, 25.4–25.7%, 52.1–52.2%, respectively. The Xanthosoma and Colocasia starches had significantly low levels (0.12–0.24%) of lipid, with trace concentrations of crude fiber. Manihot utilissima had significantly (P ≤ 0.05) higher starch and amylopectin but lower amylose contents than Colocasia and Xanthosoma starches. Average granule sizes of Xanthosoma and Colocasia starches ranged from 4.3 to 5.6 µm and 2.5–3.4 µm, respectively. Xanthosoma and Colocasia starches showed restricted swelling and solubility patterns with high initial gelatinization temperatures ranging from 78.3 to 78.5C and 74.6–74.8C, respectively. Between 19.0–19.2% and 16.8–17.1% soluble carbohydrates were obtained from Xanthosoma and Colocasia starches, respectively, at 95C. The Xanthosoma starches had higher peak, hot paste and cooked paste viscosities and stability than Colocasia starches.

PRACTICAL APPLICATIONS

This study shows that the application of cocoyam starches in food would depend largely on the knowledge of their physicochemical properties which differed with the cultivars. The properties of importance include composition, granular characteristics, swelling, solubility and pasting characteristics. The low lipid content of Xanthosoma and Colocasia starches was important to their functionality because lipid complexes with carbohydrates and reduce swelling and solubility of starches by restricting gelatinization. Xanthosoma starches had significantly higher amylopectin but lower amylose contents than Colocasia starches. The relatively high amylose contents and smaller granular characteristics were associated with the low swelling and solubility patterns of starches from both cultivars. Xanthosoma starch had higher solubilities than Colocasia starch at higher temperatures (80–95C). Xanthosoma brasillience and Xanthosoma sagittifolium starches had superior viscosity stabilities than Colocasia antiquorum and Colocasia esculenta starches, and would be useful in baked products like biscuits, cakes and breads. C. esculenta and C. antiquorum starches would be desirable in sauces, soups and as thickeners in products requiring continuous heating and stirring where viscosity is not desired.
EFFECT OF A DEFICIT IRRIGATION REGIME ON THE QUALITY OF WINES MADE FROM WHITE GRAPES (VITIS VINIFERA L.) GROWN IN SEMIARID AREAS
Authors: LÓPEZ MARÍA‐ISABEL , SÁNCHEZ MARÍA‐TERESA , RAMÍREZ PILAR , MORALES JOSÉ
Published: June 2009

The dependence of wine quality on the irrigation management strategies in Vitis vinifera L. was tested from 1999 to 2002. A drip‐irrigation experiment was performed on white grapes of the cultivars Baladí, Airén, Montepila, Muscat Blanc à Petits Grains and Pedro Ximénez, grafted and vineyard‐planted in 1995 in Cabra (Cordoba, Spain). Treatments consisted of a nonirrigated control and an experimental deficit irrigation, in which water was applied from fruit set until near harvest. A total of 19 analytical parameters were measured, including alcohols, total phenol content and optical density as well as ethanol, pH, total acidity and dry extract. Wines were evaluated for their visual characteristics, aroma, taste and finish. The irrigation treatment contributed to a higher dry extract, and an increase in malic acid and potassium in wines. There was a decrease in pH, isobutanol and isoamyl alcohols with increasing water application. Sensory evaluation ranked irrigated over nonirrigated wines with the only exception of the wines of Muscat Blanc à Petits Grains. The main defects of nonirrigated wines were attributed to visual characteristics and poorer taste quality.

PRACTICAL APPLICATIONS

Proper irrigation management, i.e., optimizing both the timing and the amount of water supplied, plays a significant role in wine quality and is especially important in arid and semiarid areas. The aim of this study was to ascertain the effect of irrigation in wine quality. In this study, irrigation was applied only during periods in which water stress might affect production and harvest quality. The chemical results ranked irrigated over nonirrigated wines and Muscat Blanc à Petits Grains over other cultivars, regarding their quality. Sensory evaluation ranked irrigated over nonirrigated wines with the only exception of the wines of Muscat Blanc à Petits Grains. Therefore, deficit irrigation during berry development and ripening appears to be a promising technique for the production of quality young wines in semiarid achieving a compromise between aroma and taste quality.
Management control of a meal experience: comments on the Five Aspects Meal Model
Authors: Jönsson Peter , Knutsson Hans
Published: June 2009

The Five Aspects Meal Model (FAMM) is a structured approach towards explaining what makes up an entire meal experience. One aspect in particular, the management control system, has a clear potential of being developed to increase the practical impact of the model. Scholars suggest that the management control system aspect works backstage, where matters of computer work, handling statistics, marketing, work organization and dealing with labour law constitute the essence of management control. Management control, however, is widely treated in other fields of research predominantly as a means for influencing behaviour and implementing strategy. The paper discusses the concept of management control and suggests an extended view on the management control system aspect of the FAMM. The upshot is that the management control system aspect could be viewed as a means to influence all the other four aspects through behavioural control of decision‐making.
Noun Incorporation: Essentials and Extensions
Authors: Massam Diane
Published: June 2009

This paper presents an overview of the principal debates in the literature on noun incorporation, citing key examples and references. There has been much discussion about which constructions can rightly fall under the term ‘noun incorporation’; for example, compounding, denominal, deverbal, light verb, conflation, and narrow scope indefinite constructions have all been treated as noun incorporation constructions. In addition, there has been much discussion about where in the grammar noun incorporation should be handled: the lexicon or the syntax. This debate has shifted with the development of theories without a clear lexicon–syntax division. In the early studies, the main focus was on the morphology of noun incorporation, but in recent years, the focus has shifted to understanding the semantics of the construction, including semantic incorporation, pseudo noun incorporation, detransitivizing, and noun stripping constructions. In addition, there have been many empirical studies over the years exploring subject and modifier incorporation, incorporation of larger phrases and other topics. Noun incorporation studies also intersect with other areas such as bare nominals, complex predicates, possessor raising constructions, and classifier systems. These issues are reviewed in this paper.
Extralysosomal Protein Degradation in Myofibrillar Myopathies
Authors: Olivé Montse
Published: June 2009

Myofibrillar myopathies (MFMs) are a group of heterogeneous muscle disorders morphologically defined by the presence of foci of dissolution of the myofibrils, accumulation of the products of myofibrillar degradation and ectopic expression of multiple proteins. MFMs represent the paradigm of conformational protein diseases of skeletal and cardiac muscles. Protein aggregation in MFMs is now considered to be the result of a failure of the extralysosomal proteolytic degradation system. Several factors including mutant proteins, aggresome formation and oxidative stress may compromise the ubiquitin–proteasome system, promoting the accumulation of potentially toxic protein aggregates within muscle cells.
Quaternary Volcanic‐Related Acid Hydrothermal Alteration in the Ugusu Silica Stone Deposit, Western Izu Peninsula, Central Japan: Geology and Alteration
Authors: Hamasaki Satoshi
Published: June 2009

Acid alteration areas accompanying Quaternary volcanoes are widespread in the western Izu Peninsula, central Japan. The Ugusu alteration area is the largest among them and is mined for “silica stone” at the silica body in the core of the alteration area. Silica zone defined by previous studies is subdivided into highly leached brecciated silica zone and residual silica zone, which extend along a NNW‐SSE–NNE‐SSW direction of fractures/faults. Fe‐rich, alunite, advanced argillic alteration, and intermediate argillic alteration zones occur toward the outside surrounding the two silica zones. The ascent of acid hydrothermal fluid would be responsible for the silica zones and surrounding alteration zones at an earlier stage, while the hydrothermal brecciation and silica veins were caused by a limited supply of silica‐saturated fluids at later stages. Based on the available mineral stability relations and fluid inclusion thermometries, the formation temperatures are estimated to be: >300°C for the residual silica zone; >290°C for the diaspore association in the advanced argillic alteration zone; and <260°C for the kaolinite association in the intermediate argillic alteration zone. The later stage quartz druses have been formed at 200–260°C. The Ugusu–Fukata acid hydrothermal systems were active at 1.5–1.2 Ma, which were temporally related to the Tanaba Andesite volcanism. Hydrothermal system at the Seikoshi gold–silver deposit survived until 0.7 Ma after the volcanism. In the western half of the Izu Peninsula, subduction of the Philippine Sea plate underneath the Suruga Trough caused nearly N–S‐trending maximum horizontal compressive stress (σHmax) and the resultant formation of similarly trending alteration areas and Au‐Ag vein‐type deposits in the Ugusu‐Toi‐Seikoshi area. From a practical viewpoint, at the Ugusu silica stone deposit, the fracture‐controlled vertical morphology of the silica body provides an important guide for exploration. Because the alteration zones occur both in the lower and upper sides of the silica bodies, it is important to make sure to which side the alteration zones correspond.
Alteration Mechanisms of Chromian‐Spinel during Serpentinization at Wadi Sifein Area, Eastern Desert, Egypt
Authors: Khalil Khalil I. , El‐Makky Ahmed M.
Published: June 2009

Wadi Sifein podiform chromite deposits, Central Eastern Desert of Egypt, are hosted by fully serpentinized peridotite that is a part of the dismembered Pan‐African ophiolite complexes. Relics of primary minerals and the chemical characters indicate that the ophiolitic rocks were derived from depleted mantle peridotite of harzburgite and subordinate dunite compositions. The mantle rocks were initially formed at a mid‐oceanic ridge and subsequently thrust at a supra‐subduction zone. The chromite mineralization at Wadi Sifein area displays either pod‐shaped bodies with massive and lumpy chromitite appearance or dissemination of chromian‐spinel in serpentinite matrix. The podiform chromitite exhibits a very limited compositional range in terms of Cr# [Cr/(Cr + Al) atomic ratio] and Mg# [Mg/(Mg + Fe) atomic ratio]. The chromian‐spinel, however, frequently displays optical and geochemical zoning. Four zones can be identified from core to edge: inner core representing the original composition of the chromian‐spinel; narrow Cr‐rich ferritchromit zone; wide ferritchromit zone; and outer Cr‐magnetite/magnetite zone. The zonation of chromian‐spinel is interpreted to be a result of serpentinization rather than magmatic or metamorphic processes. The geochemical data obtained from the chromitite and chromian‐spinel was statistically processed using discriminant and R‐mode factor analyses. Two trends, minor and major, were achieved considering the formation of ferritchromit. The minor trend is controlled by the redistribution of trivalent cations, where Cr2O3 increased on the expense mainly of Al2O3 and to less extent Fe2O3 to form zone II during the peak of serpentinization. The major trend of alteration, however, is explained by the exchange between Mg‐Fe2+ rather than Cr, Al, and Fe3+ to form zone III. Kammererite formation was accompanied the formation of zones III and IV at a 314°C temperature of formation.
Regional examination shows potential for native feedstock options for cellulosic biofuel production
Authors: STORK JOZSEF , MONTROSS MICHAEL , SMITH RAY , SCHWER LAURA , CHEN WEI , REYNOLDS MEGAN , PHILLIPS TIMOTHY , COOLONG TIMOTHY , DEBOLT SETH
Published: June 2009

Kentucky, as with many regions around the globe, has a relatively long growing season with significant rainfall that could produce sizeable quantities of perennial herbaceous and woody biomass on land that does not compete with food crops. Additionally, there are limited options for renewable power production from low carbon sources such as solar‐photovoltaic, wind and hydroelectric. Recent studies have shown that producing renewable energy from perennial cellulosic crops, as opposed to starch‐based biofuel crops, will have a carbon‐mitigating outcome. Currently, there is a lack of data regarding regionally suitable genotypes. Herein, we establish baseline values for multiple entry selections of three native C4 grass species, switchgrass (SW) (Panicum virgatum L.), eastern gamagrass (EG) (Trispicum dactyloides L.) and big bluestem (BB) (Andropogon gerardii Vitman). Yield potential examined over 7 years showed that environment, species and entries had a significant impact on yield, but EG had higher total yield over the duration of the study. Cellulosic biofuel potential was examined by measurement of saccharification efficiency, relative lignocellulosic energy density, cellulose content and lignin content during three growing seasons. EG had significantly higher digestibility rate than SW and BB. Underlying this was a negative correlation between lignification and saccharification efficiency. However, higher lignin content and higher cellulose content among SW entries resulted in higher energy density relative to EG and BB. These data reveal that locally bred EG varieties were most suited to cellulosic ethanol production under the growing conditions of central Kentucky, USA, compared with SW and BB and suggest the importance of regional examination.
Active Vibration Control for a Machine Tool With Parallel Kinematics and Adaptronic Actuator
Authors: Ast Alexandra , Eberhard Peter
Published: June 2009

The use of adaptronic components opens up interesting new possibilities for modern machine tools such as parallel kinematics. In this paper, two active vibration control concepts are designed for an adaptronic component of a parallel kinematic machine tool. The machine tool is modeled as a flexible multibody system model including a nonlinear flatness-based position control. Both the combination of a frequency shaped linear quadratic regulator with an active damping concept in a high authority control/low authority control approach and the H2 optimal control with gain scheduling show a high potential in the simulation to significantly increase the disturbance rejection or the tracking performance of the machine tool.
A Large Deformation Planar Finite Element for Pipes Conveying Fluid Based on the Absolute Nodal Coordinate Formulation
Authors: Stangl Michael , Gerstmayr Johannes , Irschik Hans
Published: June 2009

A novel planar pipe finite element conveying fluid with steady flow, suitable for modeling large deformations in the framework of the Bernoulli–Euler beam theory, is presented. The element is based on a third order planar beam finite element, introduced by Berzeri and Shabana (2000, “Development of Simple Models for the Elastic Forces in the Absolute Nodal Co-Ordinate Formulation,” J. Sound Vib., 235(4), pp. 539–565), applying the absolute nodal coordinate formulation. The equations of motion of the pipe finite element are derived using an extended version of Lagrange’s equations of the second kind taking into account the flow of fluid; in contrast, most derivations in the literature are based on Hamilton’s principle or the Newtonian approaches. The advantage of this element in comparison to classical large deformation beam elements, which are based on rotations, is the direct interpolation of position and directional derivatives, which simplifies the equations of motion considerably. As an advantage, Lagrange’s equations of the second kind offer a convenient connection for introducing fluids into multibody dynamic systems. Standard numerical examples show the convergence of the deformation for increasing number of elements. For a cantilever pipe, the critical flow velocities for increasing number of pipe elements are compared with existing works, based on Euler elastica beams and moving discrete masses. The results show good agreement with the reference solutions applying only a small number of pipe finite elements.
Direct Linearization of Continuous and Hybrid Dynamical Systems
Authors: Parish Julie J. , Hurtado John E. , Sinclair Andrew J.
Published: June 2009

Nonlinear equations of motion are often linearized, especially for stability analysis and control design applications. Traditionally, the full nonlinear equations are formed and then linearized about the desired equilibrium configuration using methods such as Taylor series expansions. However, it has been shown that the quadratic form of the Lagrangian function can be used to directly linearize the equations of motion for discrete dynamical systems. This procedure is extended to directly generate linearized equations of motion for both continuous and hybrid dynamical systems. The results presented require only velocity-level kinematics to form the Lagrangian and find equilibrium configuration(s) for the system. A set of selected partial derivatives of the Lagrangian are then computed and used to directly construct the linearized equations of motion about the equilibrium configuration of interest, without first generating the entire nonlinear equations of motion. Given an equilibrium configuration of interest, the directly constructed linearized equations of motion allow one to bypass first forming the full nonlinear governing equations for the system. Examples are presented to illustrate the method for both continuous and hybrid systems.
A Gauge-Invariant Formulation for Constrained Mechanical Systems Using Square-Root Factorization and Unitary Transformation
Authors: Aghili Farhad
Published: June 2009

A gauge-invariant formulation for deriving the dynamic equations of constrained multibody systems in terms of (reduced) quasivelocities is presented. This formulation does not require any weighting matrix to deal with the gauge-invariance problem when both translational and rotational components are involved in the generalized coordinates or in the constraint equations. Moreover, in this formulation the equations of motion are decoupled from those of constrained force, and each system has its own independent input. This allows the possibility to develop a simple force control action that is totally independent from the motion control action facilitating a hybrid force/motion control. Tracking force/motion control of constrained multibody systems based on a combination of feedbacks on the vectors of the quasivelocities and the configuration-variables are presented.
On Lugre Friction Model to Mitigate Nonideal Vibrations
Authors: Felix Jorge Luis Palacios , Balthazar José Manoel , Brasil Reyolando M. L. R. F. , Pontes Bento Rodrigues
Published: June 2009

In this paper, a nonideal mechanical system with the LuGre friction damping model is considered. The mechanical model of the system is an oscillator not necessarily linear connected with an unbalanced motor of excitation with limited power supply. The control of motion and the attenuation of the Sommerfeld effect of the considered nonideal system are analyzed in this paper. The mathematical model of the system is represented by coupled nonlinear differential equations. The identification of some interesting nonlinear phenomenon in the transient and steady state motion of the system during the passage through resonance (using applied voltages at dc motor as control parameter) is investigated in detail using numerical simulation.
Debris flow triggering by impulsive loading: mechanical modelling and case studies
Authors: Bovis M. J. , Dagg B. R.
Published: June 2009

A mechanism is proposed by which debris flows can be triggered through impulsive loading. Momentum transferred from hillslope failures to steep stream bed materials may be sufficient to initiate a debris flow where one may not otherwise occur. An important parameter in the momentum transfer is the planimetric angle between the slide path axis and the stream channel axis. Preliminary stability equations for both drained and undrained loading are developed from formulae commonly used to assess stream channel stability. Case studies from two basins in the southern Coast Mountains of British Columbia are used to illustrate the mechanisms. Key words : debris flow, triggering, mechanisms, rock slide, debris slide, Coast Mountains.
Hydraulic conductivity of compacted bentonite–sand mixtures
Authors: Kenney T. C. , Veen W. A. Van , Swallow M. A. , Sungaila M. A.
Published: June 2009

In the absence of impervious natural soils, compacted mixtures of bentonite and sand have been used to form barriers to fluids, and the focus of this paper is on the hydraulic conductivity behaviour of these compacted mixtures. Results of laboratory investigations are presented to show the influences of bentonite–sand content, compaction water content, system chemistry, and changes of system chemistry. Some of the findings are as follows: (i) low hydraulic conductivity requires continuity of the bentonite matrix within the mixture, and this in turn requires both adequate bentonite content and adequate bentonite distribution (i.e., mixing); (ii) in well-compacted mixtures containing up to 20% bentonite in dry mass, sand forms the load-supporting framework and gives the mixtures dimensional stability at the macro level (crack resistance); and (iii) the hydraulic conductivity of mixtures containing freshwater, high-swell bentonite, when permeated with a strong saline solution, increased by only small amounts, suggesting that the fabric of bentonite enclosed within the sand framework was little influenced by this change of system chemistry. Key words : mixture, bentonite, sand, permeability, laboratory study.
General News
Authors: Painter Martin , Thomas Laura
Published: June 2009

Traditional Search + Interim Management = A Winning Combination.
VARIATIONAL PRINCIPLE FOR SUBADDITIVE SEQUENCE OF POTENTIALS IN BUNDLE RANDOM DYNAMICAL SYSTEMS
Authors: MA XIANFENG , CHEN ERCAI
Published: June 2009

The topological pressure is defined for subadditive sequence of potentials in bundle random dynamical systems. A variational principle for the topological pressure is set up in a very weak condition. The result may have some applications in the study of multifractal analysis for random version of nonconformal dynamical systems.
ON ONE-DIMENSIONAL STOCHASTIC DIFFERENTIAL EQUATIONS INVOLVING THE MAXIMUM PROCESS
Authors: BELFADLI R. , HAMADÈNE S. , OUKNINE Y.
Published: June 2009

We prove existence and pathwise uniqueness results for four different types of stochastic differential equations (SDEs) perturbed by the past maximum process and/or the local time at zero. Along the first three studies, the coefficients are no longer Lipschitz. The first type is the equation [Formula: see text] The second type is the equation [Formula: see text] The third type is the equation [Formula: see text] We end the paper by establishing the existence of strong solution and pathwise uniqueness, under Lipschitz condition, for the SDE [Formula: see text]
RANDOM ATTRACTOR FOR THE 3D VISCOUS STOCHASTIC PRIMITIVE EQUATIONS WITH ADDITIVE NOISE
Authors: GAO HONGJUN , SUN CHENGFENG
Published: June 2009

In this article, we obtain the existence and uniqueness of strong solutions to 3D viscous stochastic primitive equations (PEs) and the random attractor for 3D viscous PEs with additive white noise.
GLOBAL SOLUTIONS AND BOUNDEDNESS OF STOCHASTIC FUNCTIONAL KOLMOGOROV SYSTEM WITH INFINITE DELAY
Authors: XU YONG , WU FUKE , HU SHIGENG
Published: June 2009

This paper investigates the existence and boundedness of the global positive solutions for stochastic Kolmogorov system with infinite delay. We obtain two classes of sufficient conditions to guarantee these properties. These two classes of the conditions show that the system is dominated by deterministic part or stochastic part respectively. By the M-matrix technique, we conveniently compare our results. Finally, a Lotka–Volterra model as a special case is given to illustrate our idea.
PHENOMENOLOGICAL MODELING FOR PORE OPENING, CLOSURE AND RUPTURE OF THE GUV MEMBRANE
Authors: FAN HUI , CHEN YAN , SZE K. Y.
Published: June 2009

In this paper, the pore opening and closure on the giant unilamellar vesicle GUV membrane are studied under different theoretical schemes. The opening process is considered as a dynamics process; while the closure process is considered as a quasi-static process. The opening criterion is set based on an energy release rate theory, similar to the Griffith theory for crack initiation. On the other hand, the closure process is described by a non-equilibrium thermodynamic theory. When the size of initial pore is smaller than a critical value, the pore is stable, and followed by the closure process. Otherwise, the pore is unstable, which leads to the rupture of the vesicle.
NEW MECHANICS OF SPINAL INJURY
Authors: IVANCEVIC VLADIMIR G.
Published: June 2009

The prediction and prevention of spinal injury is an important aspect of preventive medical science. The spine, or vertebral column, represents a chain of 26 movable vertebral bodies, joint together by transversal viscoelastic intervertebral discs and longitudinal elastic tendons. This paper proposes a new locally–coupled loading–rate hypothesis, which states that the main cause of both soft- and hard-tissue spinal injury is a localized Euclidean jolt, or SE(3)-jolt, an impulsive loading that strikes a localized spinal section in several coupled degrees-of-freedom simultaneously. To show this, based on the previously defined covariant force law, we formulate the coupled Newton–Euler dynamics of the local spinal motions and derive from it the corresponding coupled SE(3)-jolt dynamics (see our recent papers on new mechanics of traumatic brain injury [V. G. Ivancevic, New mechanics of traumatic brain injury, Cogn. Neurodyn. Springer (Online)]. and generic musculo-skeletal injury [V. G. Ivancevic, New mechanics of generic musculo-skeletal injury, Biophys. Rev. Let. (2009) (in press)]). The SE(3)-jolt is the main cause of two basic forms of spinal injury: (i) hard-tissue injury of local translational dislocations; and (ii) soft-tissue injury of local rotational disclinations. Both the spinal dislocations and disclinations, as caused by the SE(3)-jolt, are described using the Cosserat multipolar viscoelastic continuum model.
A NEW EFFICIENT APPROACH FOR MODELING AND SIMULATION OF NANO-SWITCHES UNDER THE COMBINED EFFECTS OF INTERMOLECULAR SURFACE FORCES AND ELECTROSTATIC ACTUATION
Authors: MOJAHEDI MAHDI , MOEENFARD HAMID , AHMADIAN MOHAMMAD TAGHI
Published: June 2009

This paper applies the homotopy perturbation method to the simulation of the static response of nano-switches to electrostatic actuation and intermolecular surface forces. The model accounts for the electric force nonlinearity of the excitation and for the fringing field effect. Using a mode approximation in the Galerkin projection method, the nonlinear boundary value differential equation describing the statical behavior of nano-switch is reduced to a nonlinear algebraic equation which is solved using the homotopy perturbation method. The number of included terms in the perturbation expansion for achieving a reasonable response has been investigated. Three cases have been specifically studied. These cases correspond to when the effective external force is the electrostatic force, the combined electrostatic and Casimir force and the combined electrostatic and van der Waals force. In all three cases the pull-in characteristics has been investigated thoroughly. Results have been compared with numerical results and also analytical results available in the literature. It was found that HPM modifies the overestimation of N/MEMS instability limits reported in the literature and can be used as an effective and accurate design tool in the analysis of N/MEMS.
Evolutionary Roles of Upstream Open Reading Frames in Mediating Gene Regulation in Fungi
Authors: Hood Heather M. , Neafsey Daniel E. , Galagan James , Sachs Matthew S.
Published: June 2009

Upstream open reading frames (uORFs) are frequently present in the 5′-leader regions of fungal mRNAs. They can affect translation by controlling the ability of ribosomes that scan from the mRNA 5′ end to reach the downstream genic reading frame. The translation of uORFs can also affect mRNA stability. For several genes, including Saccharomyces cerevisiae GCN4, S. cerevisiae CPA1, and Neurospora crassa arg-2, regulation by uORFs controls expression in response to specific physiological signals. The roles of many uORFs that are identified by genome-level approaches, as have been initiated for Saccharomyces, Aspergillus, and Cryptococcus species, remain to be determined. Some uORFs may have regulatory roles, while others may exist to insulate the genic reading frame from the negative impacts of upstream translation start sites in the mRNA 5′ leader.
Explorations in statistics: hypothesis tests and P values
Authors: Curran-Everett Douglas
Published: June 2009

Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This second installment of Explorations in Statistics delves into test statistics and P values, two concepts fundamental to the test of a scientific null hypothesis. The essence of a test statistic is that it compares what we observe in the experiment to what we expect to see if the null hypothesis is true. The P value associated with the magnitude of that test statistic answers this question: if the null hypothesis is true, what proportion of possible values of the test statistic are at least as extreme as the one I got? Although statisticians continue to stress the limitations of hypothesis tests, there are two realities we must acknowledge: hypothesis tests are ingrained within science, and the simple test of a null hypothesis can be useful. As a result, it behooves us to explore the notions of hypothesis tests, test statistics, and P values.
Regulated Expression of Surface AMPA Receptors Reduces Excitotoxicity in Auditory Neurons
Authors: Chen Zhiqiang , Peppi Marcello , Kujawa Sharon G. , Sewell William F.
Published: June 2009

Dynamic regulation of the expression of surface AMPA receptors (AMPARs) is a key mechanism to modulate synaptic strength and efficacy in the CNS and also to regulate auditory sensitivity. Here we address the role of surface AMPAR expression in excitotoxicity by blocking clathrin-mediated AMPAR endocytosis in auditory neurons. We used a membrane-permeable, dynamin-derived, myristoylated peptide (myr-Dyn) to inhibit surface AMPAR endocytosis induced by glutamate receptor agonists in culture and by noise exposure in vivo. Myr-Dyn infused into the mouse cochlea induced excitotoxic responses to acoustic stimuli that were normally not excitotoxic. These included vacuolization in the nerve terminals and spiral ganglion as well as irreversible auditory brain stem response threshold shifts. In cultured spiral ganglion neuronal cells, blockade of the reduction of surface AMPARs exacerbated neuronal death by incubation with N-methyl-d-aspartate and AMPA. This excitotoxic neuronal death could be prevented by calpeptin, a calpain-specific inhibitor. These results suggest that the reduction of surface AMPAR by endocytosis during excitatory stimulation plays an important role in limiting the excitotoxic damage to the neuron.
Inhibitory Inputs to Hippocampal Interneurons Are Reorganized in Lis1 Mutant Mice
Authors: Jones Daniel L. , Baraban Scott C.
Published: June 2009

Epilepsy and brain malformation are commonly associated with excessive synaptic excitation and decreased synaptic inhibition of principal neurons. However, few studies have examined the state of synaptic inhibition of interneurons in an epileptic, malformed brain. We analyzed inhibitory inputs, mediated by γ-aminobutyric acid (GABA), to hippocampal interneurons in a mouse model of type 1 lissencephaly, a neurological disorder linked with severe seizures and brain malformation. In the disorganized hippocampal area CA1 of Lis1+/− mice, we initially observed a selective displacement of fast-spiking, parvalbumin-positive basket-type interneurons from stratum oriens (SO) locations to s. radiatum and s. lacunosum-moleculare (R/LM). Next, we recorded spontaneous and miniature inhibitory postsynaptic currents (sIPSCs and mIPSCs) onto visually identified interneurons located in SO or R/LM of Lis1+/− mice and age-matched littermate controls. We observed significant, layer-specific reorganizations in GABAergic inhibition of interneurons in Lis1 mutant mice. Spontaneous IPSC frequency onto SO interneurons was significantly increased in hippocampal slices from Lis1+/− mice, whereas mIPSC mean amplitude onto these interneurons was significantly decreased. In addition, the weighted decay times of sIPSCs and mIPSCs were significantly increased in R/LM interneurons. Taken together, these findings illustrate the extensive redistribution and reorganization of inhibitory connections between interneurons that can take place in a malformed brain.
Microarray profiling revealsCXCR4ais downregulated by blood flow in vivo and mediates collateral formation in zebrafish embryos
Authors: Packham Ian M. , Gray Caroline , Heath Paul R. , Hellewell Paul G. , Ingham Philip W. , Crossman David C. , Milo Marta , Chico Timothy J. A.
Published: June 2009

The response to hemodynamic force is implicated in a number of pathologies including collateral vessel development. However, the transcriptional effect of hemodynamic force is extremely challenging to examine in vivo in mammals without also detecting confounding processes such as hypoxia and ischemia. We therefore serially examined the transcriptional effect of preventing cardiac contraction in zebrafish embryos which can be deprived of circulation without experiencing hypoxia since they obtain sufficient oxygenation by diffusion. Morpholino antisense knock-down of cardiac troponin T2 ( tnnt2) prevented cardiac contraction without affecting vascular development. Gene expression in whole embryo RNA from tnnt2 or control morphants at 36, 48, and 60 h postfertilization (hpf) was assessed using Affymetrix GeneChip Zebrafish Genome Arrays (>14,900 transcripts). We identified 308 differentially expressed genes between tnnt2 and control morphants. One such ( CXCR4a) was significantly more highly expressed in tnnt2 morphants at 48 and 60 hpf than controls. In situ hybridization localized CXCR4a upregulation to endothelium of both tnnt2 morphants and gridlock mutants (which have an occluded aorta preventing distal blood flow). This upregulation appears to be of functional significance as either CXCR4a knock-down or pharmacologic inhibition impaired the ability of gridlock mutants to recover blood flow via collateral vessels. We conclude absence of hemodynamic force induces endothelial CXCR4a upregulation that promotes recovery of blood flow.
eIF2α kinases GCN2 and PERK modulate transcription and translation of distinct sets of mRNAs in mouse liver
Authors: Dang Do An N. , Kimball Scot R. , Cavener Douglas R. , Jefferson Leonard S.
Published: June 2009

In eukaryotes, selective derepression of mRNA translation through altered utilization of upstream open reading frames (uORF) or internal ribosomal entry sites (IRES) regulatory motifs following exposure to stress is regulated at the initiation stage through the increased phosphorylation of eukaryotic initiation factor 2 on its α-subunit (eIF2α). While there is only one known eIF2α kinase in yeast, general control nonderepressible 2 (GCN2), mammals have evolved to express at least four: GCN2, heme-regulated inhibitor kinase (HRI), double-stranded RNA-activated protein kinase (PKR), and PKR-like endoplasmic reticulum-resident kinase (PERK). So far, the main known distinction among these four kinases is their activation in response to different acute stressors. In the present study, we used the in situ perfused mouse liver model and hybridization array analyses to assess the general translational response to stress regulated by two of these kinases, GCN2 and PERK, and to differentiate between the downstream effects of activating GCN2 versus PERK. The resulting data showed that at least 2.5% of mouse liver mRNAs are subject to derepressed translation following stress. In addition, the data demonstrated that eIF2α kinases GCN2 and PERK differentially regulate mRNA transcription and translation, which in the latter case suggests that increased eIF2α phosphorylation is not sufficient for derepression of translation. These findings open an avenue for more focused future research toward groups of mRNAs that code for the early cellular stress response proteins.
CMTM3, Located at the Critical Tumor Suppressor Locus 16q22.1, Is Silenced by CpG Methylation in Carcinomas and Inhibits Tumor Cell Growth through Inducing Apoptosis
Authors: Wang Yu , Li Jisheng , Cui Yan , Li Ting , Ng Ka Man , Geng Hua , Li Henan , Shu Xing-sheng , Li Hongyu , Liu Wei , Luo Bing , Zhang Qian , Mok Tony Shu Kam , Zheng Wei , Qiu Xiaoyan , Srivastava Gopesh , Yu Jun , Sung Joseph J.Y. , Chan Anthony T.C. , Ma Dalong , Tao Qian , Han Wenling
Published: June 2009

Closely located at the tumor suppressor locus 16q22.1, CKLF-like MARVEL transmembrane domain-containing member 3 and 4 (CMTM3 and CMTM4) encode two CMTM family proteins, which link chemokines and the transmembrane-4 superfamily. In contrast to the broad expression of both CMTM3 and CMTM4 in normal human adult tissues, only CMTM3 is silenced or down-regulated in common carcinoma (gastric, breast, nasopharyngeal, esophageal, and colon) cell lines and primary tumors. CMTM3 methylation was not detected in normal epithelial cell lines and tissues, with weak methylation present in only 5 of 35 (14%) gastric cancer adjacent normal tissues. Furthermore, immunohistochemistry showed that CMTM3 protein was absent in 12 of 35 (34%) gastric and 1 of 2 colorectal tumors, which was well correlated with its methylation status. The silencing of CMTM3 is due to aberrant promoter CpG methylation that could be reversed by pharmacologic demethylation. Ectopic expression of CMTM3 strongly suppressed the colony formation of carcinoma cell lines. In addition, CMTM3 inhibited tumor cell growth and induced apoptosis with caspase-3 activation. Thus, CMTM3 exerts tumor-suppressive functions in tumor cells, with frequent epigenetic inactivation by promoter CpG methylation in common carcinomas. [Cancer Res 2009;69(12):5194–201]
Microalterations of Inherently Unstable Genomic Regions in Rat Mammary Carcinomas as Revealed by Long Oligonucleotide Array-Based Comparative Genomic Hybridization
Authors: Adamovic Tatjana , McAllister Donna , Guryev Victor , Wang Xujing , Andrae Jaime Wendt , Cuppen Edwin , Jacob Howard J. , Sugg Sonia L.
Published: June 2009

The presence of copy number variants in normal genomes poses a challenge to identify small genuine somatic copy number changes in high-resolution cancer genome profiling studies due to the use of unpaired reference DNA. Another problem is the well-known rearrangements of immunoglobulin and T-cell receptor genes in lymphocytes (a commonly used reference), which may misdirect the researcher to a locus with no relevance in tumorigenesis. We here show real gains of the IgG heavy chain V gene region in carcinogen-induced rat mammary tumor samples after normalization to paired mammary gland, a tissue without lymphocyte infiltration. We further show that the segmental duplication region encompassing the IgG heavy chain V genes is a copy number variant between the susceptible (SS) and the resistant (BN) to mammary tumor development inbred rat strains. Our data suggest that the already inherently unstable genomic region is a convenient target for additional structural rearrangements (gains) at the somatic level when exposed to a carcinogen (7,12-dimethylbenz[a]anthracene), which subsequently seem to benefit tumor development in the mammary gland of the susceptible strain. Thus, the selection of an appropriate reference DNA enabled us to identify immunoglobulin genes as novel cancer targets playing a role in mammary tumor development. We conclude that control DNA in array-based comparative genomic hybridization experiments should be selected with care, and DNA from pooled spleen (contains immature lymphocytes and is used as reference in animal studies) or blood may not be the ideal control in the study of primary tumors. [Cancer Res 2009;69(12):5159–67]
Therapeutic Potential of “Rexinoids” in Cancer Prevention and Treatment
Authors: Tanaka Takemi , De Luca Luigi M.
Published: June 2009

Retinoid X receptor (RXR) is a combinatorial partner for one third of the 48 human nuclear receptor superfamily members and acts as a master coordinator of nuclear receptor signaling pathways involved in the control of cell growth and differentiation. Thus, ligand-dependent simultaneous activation of multiple pathways is an attractive strategy for molecular-targeted therapy of neoplastic disease. However, clinical trials in RXR-targeted molecular therapy with the RXR ligand (rexinoid) have yielded disappointing outcomes. In this review, we discuss a possible mechanism underlying the loss of sensitivity to rexinoid therapy. [Cancer Res 2009;69(12):4945–-47]