bluuebunny/crossref_metadata_2025 huggingface dataset:
FLOW BEHAVIOR OF AN EYRING-FLUID IN NANODOMAIN: EFFECT OF SMALL WAVY-ROUGHNESS
Authors: CHU KWANG-HUA W. , LIU SHENG-JUN
Published: December 2010

The steady velocities and volume flow rates (up to the second order) of an Eyring-fluids along the cross-section of an (approximated) wavy-rough nanotube are obtained analytically by using the verified fluid model and boundary perturbation method. Our results show that the wavy-roughness could tune the flow rate especially for larger forcing due to the larger surface-to-volume ratio and slip-velocity effect. The effects of wave number and slip length are also addressed.
FIDELITY APPROACH TO QUANTUM PHASE TRANSITIONS
Authors: GU SHI-JIAN
Published: December 2010

We review the quantum fidelity approach to quantum phase transitions in a pedagogical manner. We try to relate all established but scattered results on the leading term of the fidelity into a systematic theoretical framework, which might provide an alternative paradigm for understanding quantum critical phenomena. The definition of the fidelity and the scaling behavior of its leading term, as well as their explicit applications to the one-dimensional transverse-field Ising model and the Lipkin–Meshkov–Glick model, are introduced at the graduate-student level. Besides, we survey also other types of fidelity approach, such as the fidelity per site, reduced fidelity, thermal-state fidelity, operator fidelity, etc; as well as relevant works on the fidelity approach to quantum phase transitions occurring in various many-body systems.
PARAMETER FLUCTUATION-INDUCED PATTERN TRANSITION IN THE COMPLEX GINZBURG–LANDAU EQUATION
Authors: MA JUN , JA YA , TANG JUN , CHEN YONG
Published: December 2010

Parameter fluctuation, which is often induced by the noise, temperature, deformation of the media etc., plays an important role in changing the dynamics of the system. In this paper, the problem of parameter fluctuation-induced pattern transition in the Complex Ginzburg–Landau equation (CGLE) is investigated. At first, the perpendicular-gradient initial values are used to generate spiral wave and spiral turbulence under appropriate parameters. At second, the parameter is perturbed with the periodical and/or random signal to simulate the parameter fluctuation, respectively. Then a class of linear error feedback is used to induce transition of the spiral wave and spiral turbulence. It is found that target waves can be induced by the complete feedback forcing, while the local feedback forcing seldom induce a target wave. In the case of spiral turbulence, spiral wave is generated and the spiral turbulence is removed by the new appeared spiral wave as the linear error feedback began to work on the whole media. Finally, the common negative feedback is also used to control the parameter-fluctuated CGLE, and the results are compared with the linear error feedback control, it is found that the whole system become homogeneous when the negative feedback is imposed on the whole media, and the local negative feedback can induce new target wave to remove the spiral wave while it is in vain to generate new target or spiral wave to overcome and eliminate the spiral turbulence.
EFFECT OF OIL PALM FIBRES VOLUME FRACTION ON MECHANICAL PROPERTIES OF POLYESTER COMPOSITES
Authors: YOUSIF B. F.
Published: December 2010

The effect of two types of oil palm fibres (bunch and fruit) on mechanical properties of polyester composites is examined in the current work considering different volume fractions. Tensile, compression, and flexural properties of the composites were investigated. In addition to that, tensile strengths were calculated theoretically using Hirsch model. Scanning electron microscope (SEM) was used to observe the fracture mechanism of the specimens. Single fibre pull-out tests were performed to determine the interfacial shear strength between polyester resin and both types of oil palm fibres. Results revealed that both types of oil palm fibres enhanced the mechanical performance of polyester composites. At a higher volume fraction (40–50%), tensile strength of the polyester composite was improved, i.e., 2.5 times improvement in the tensile strength value. Experimental tensile strength values of oil palm bunch/polyester composites have a good correlation with the theoretical results, especially at low volume fractions of fibre. Flexural strength of polyester worsened with oil palm fibres at all volume fractions of fibre.
OPTICAL BISTABILITY VIA INCOHERENT PUMPING FIELDS IN SEMICONDUCTOR QUANTUM WELLS
Authors: WANG HUI , ZHANG HONG-TAO , WANG ZHI-PING
Published: December 2010

Under the non-resonant condition, we investigated the optical bistability (OB) in a three-level quantum well system inside a unidirectional ring cavity. We find that the incoherent pumping fields and the quantum interference induced by incoherent pumping fields can affect the optical bistability dramatically, which can be used to manipulate efficiently the threshold intensity and the hysteresis loop. These results are achieved by applying the two incoherent pumping fields, so they are very different from the conventional schemes that coherent driving fields are used to control the optical bistability. Thus, it may provide some new possibilities for technological applications in optoelectronics and solid-state quantum information science.
SIMULATION STUDY OF NOISE-ENHANCED STABILITY AND RESONANT ACTIVATION IN A BISTABLE SYSTEM INDUCED BY TIME DELAY
Authors: LI CHUN , DU LUCHUN , MEI DONGCHENG
Published: December 2010

The thermal activation problem of a bistable system driven by correlated noises with time delay is investigated by means of numerical simulations. The simulation results indicate: (1) For the case of the bistable system with linear delay, the phenomenon of noise enhanced stability (NES) is enforced by increasing delay time τ as the multiplicative noise intensity D is smaller, but is weakened as D is larger. (2) For the case of the bistable system with cubic delay, the NES becomes faintness as τ increases. (3) For the case of the bistable system with global delay, the NES is still restrained by increasing τ with smaller D, and in some circumstances, the activation rate as a function of τ exists a peak structure, which demonstrating the emergence of resonant activation.
HYPERCHAOS FROM AN AUGMENTED LÜ SYSTEM
Authors: BAO BOCHENG , XU JIANPING , LIU ZHONG , MA ZHENGHUA
Published: December 2010

This letter introduces a hyperchaotic system from the Lü system [Lü et al., 2004] with a linear state feedback controller. This hyperchaotic system has more complex dynamical behaviors, and can generate 4-scroll hyperchaotic attractor and 2-scroll chaotic attractor under different control parameters. In particular, the system can also exhibit novel coexisting intermittent chaotic orbits. Theoretical analyses and simulation experiments are conducted to investigate the dynamical behaviors of the proposed hyperchaotic system.
DEFINITION OF DISTANCE FOR MARKED POINT PROCESS DATA AND ITS APPLICATION TO RECURRENCE PLOT-BASED ANALYSIS OF EXCHANGE TICK DATA OF FOREIGN CURRENCIES
Authors: SUZUKI SATOSHI , HIRATA YOSHITO , AIHARA KAZUYUKI
Published: December 2010

Recurrence plots are effective in analyzing nonstationary time series. Further, it is desirable to make the recurrence plot-based analysis applicable to marked point process data such as foreign exchange tick data. In this paper, we define a distance for marked point process data and establish the basis for further analyses. We also show that foreign exchange tick data have serial dependence using recurrence plots and the random shuffle surrogate method.
COUPLED-EXPANDING MAPS FOR IRREDUCIBLE TRANSITION MATRICES
Authors: ZHANG XU , SHI YUMING
Published: December 2010

In this paper, strictly A-coupled-expanding maps in bounded and closed subsets of complete metric spaces are investigated, where A = (aij) is an m × m irreducible transition matrix with one row-sum no less than 2. A map f is said to be strictly A-coupled-expanding in m sets Vi if f(Vi) ⊃ Vj whenever aij = 1 and the distance between any two different sets of these Vi is positive. A new result on the subshift for matrix A is obtained. Based on this result, two criteria of chaos are established, which generalize and relax the conditions of some existing results. These maps are proved to be chaotic either in the sense of both Li–Yorke and Wiggins or in the sense of both Li–Yorke and Devaney. One example is provided to illustrate the theoretical results with a computer simulation for demonstration.
Recent insights into diabetic renal injury from thedb/dbmouse model of type 2 diabetic nephropathy
Authors: Tesch G. H. , Lim A. K. H.
Published: December 2010

The db/db mouse is the most widely used animal model of type 2 diabetic nephropathy. Recent studies have utilized genetic backcrossing with transgenic mouse strains to create novel db/db strains that either lack or overexpress specific genes. These novel strains [ICAM-1−/−, CCL2−/−, MKK3−/−, osteopontin−/−, plasminogen activator inhibitor-1 (PAI-1)−/−, endothelial nitric oxide synthase−/−, SOD-Tg, rCAT-Tg] have provided valuable insights into the molecular mechanisms which promote diabetic renal injury. In addition, surgical removal of one kidney has been shown to accelerate injury in the remaining kidney of diabetic db/db mice. A number of novel therapeutic agents have also been tested in db/db mice, including inhibitors of inflammation (chemokine receptor antagonists, anti-CCL2 RNA aptamer, anti- c-fms antibody); oxidative stress (oxykine, biliverdin); the renin-angiotensin-aldosterone system (aliskiren, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, eplerenone); advanced glycation end products (AGE; pyridoxamine, alagebrium, soluble AGE receptor); angiogenesis (NM-3, anti-CXCL12 RNA aptamer, soluble Flt-1); lipid accumulation (statins, farnesoid X receptor agonists, Omacor); intracellular signaling pathways (PKC-β or JNK inhibitors); and fibrosis [transforming growth factor (TGF)-β antibody, TGF-βR kinase inhibitor, soluble betaglycan, SMP-534, CTGF-antisense oligonucleotide, mutant PAI-1, pirfenidone], which have identified potential therapeutic targets for clinical translation. This review summarizes the advances in knowledge gained from studies in genetically modified db/db mice and treatment of db/db mice with novel therapeutic agents.
Renal cortical albumin gene induction and urinary albumin excretion in response to acute kidney injury
Authors: Ware Lorraine B. , Johnson Ali C. M. , Zager Richard A.
Published: December 2010

This study evaluated the potential utility of albuminuria as a “biomarker” of acute kidney injury (AKI) and tested whether AKI induces renal expression of the normally silent albumin gene. Urine albumin concentrations were measured in mice with five different AKI models (maleate, ischemia-reperfusion, rhabdomyolysis, endotoxemia, ureteral obstruction). Albumin gene induction in renal cortex, and in antimycin A-injured cultured proximal tubular cells, was assessed (mRNA levels; RNA polymerase II binding to the albumin gene). Albumin's clinical performance as an AKI biomarker was also tested (29 APACHE II-matched intensive care unit patients with and without AKI). Results were contrasted to those obtained for neutrophil gelatinase-associated lipocalin (NGAL), an established “AKI biomarker” gene. The experimental and clinical assessments indicated albumin's equivalence to NGAL as an AKI biomarker (greater specificity in experimental AKI; slightly better receiver-operating curve in humans). Furthermore, experimental AKI markedly induced the albumin gene (mRNA/RNA polymerase II binding increases; comparable to those seen for NGAL). Albumin gene activation in patients with AKI was suggested by fivefold increases in RNA polymerase II binding to urinary fragments of the albumin gene (vs. AKI controls). Experimental AKI also increased renal cortical mRNA levels for α-fetoprotein (albumin's embryonic equivalent). A correlate in patients was increased urinary α-fetoprotein excretion. We conclude that AKI can unmask, in the kidney, the normally silent renal albumin and α-fetoprotein genes. In addition, the urinary protein data independently indicate that albuminuria, and perhaps α-fetoprotein, have substantial utility as biomarkers of acute tubular injury.
Repetitive Perforant-Path Stimulation Induces Epileptiform Bursts in Minislices of Dentate Gyrus From Rats With Kainate-Induced Epilepsy
Authors: Shao Li-Rong , Dudek F. Edward
Published: December 2010

The epileptic hippocampus has an enhanced propensity for seizure generation, but how spontaneous seizures start is poorly understood. Using whole cell and field-potential recordings, this study explored whether repetitive perforant-path stimulation at physiological frequencies could induce epileptiform bursts in dentate gyrus minislices from rats with kainate-induced epilepsy. Control slices from saline-treated rats responded to single perforant-path stimulation with an excitatory postsynaptic potential (EPSP) and a single population spike in normal medium, and repetitive stimulation at different frequencies (0.1, 1, 2, 5, 10 Hz) did not cause significant increases in the responses. Most minislices (82%) from rats with kainate-induced epilepsy also responded to single perforant-path stimulation with an EPSP and a single population spike/action potential, but some slices (18%) had a more robust response with a prolonged duration and negative DC shift or responses with two to three population spikes. Repetitive perforant-path stimulation at 5–10 Hz, however, transformed the single-spike responses into epileptiform bursts with multiple spikes in half (52%) of the slices, while lower frequency (e.g., ≤1 Hz) stimulation failed to produce these changes. The emergence of epileptiform bursts was consistently associated with a negative field-potential DC shift and membrane depolarization. The results suggest that compared with the controls, the “gate” function of the dentate gyrus is compromised in rats with kainate-induced epilepsy, and epileptiform bursts (but not full-length seizure events) can be induced in minislices by repetitive synaptic stimulation at physiological frequencies in the range of hippocampal theta rhythm (i.e., 5–10 Hz).
A Constitutive Formulation for the Linear Thermoelastic Behavior of Arbitrary Fiber‐Reinforced Composites
Authors: Usal Melek
Published: December 2010

The linear thermoelastic behavior of a composite material reinforced by two independent and inextensible fiber families has been analyzed theoretically. The composite material is assumed to be anisotropic, compressible, dependent on temperature gradient, and showing linear elastic behavior. Basic principles and axioms of modern continuum mechanics and equations belonging to kinematics and deformation geometries of fibers have provided guidance and have been determining in the process of this study. The matrix material is supposed to be made of elastic material involving an artificial anisotropy due to fibers reinforcing by arbitrary distributions. As a result of thermodynamic constraints, it has been determined that the free energy function is dependent on a symmetric tensor and two vectors whereas the heat flux vector function is dependent on a symmetric tensor and three vectors. The free energy and heat flux vector functions have been represented by a power series expansion, and the type and the number of terms taken into consideration in this series expansion have determined the linearity of the medium. The linear constitutive equations of the stress and heat flux vector are substituted in the Cauchy equation of motion and in the equation of conservation of energy to obtain the field equations.
Construction and Characterization of Insect Cell-Derived Influenza VLP: Cell Binding, Fusion, and EGFP Incorporation
Authors: Pan Yi-Shin , Wei Hung-Ju , Chang Chung-Chieh , Lin Chung-Hung , Wei Ting-Shyang , Wu Suh-Chin , Chang Ding-Kwo
Published: December 2010

We have constructed virus-like particles (VLPs) harboring hemagglutinin (HA), neuraminidase (NA), matrix protein 1 (M1) ,and proton channel protein (M2) using baculovirus as a vector in the SF9 insect cell. The size of the expressed VLP was estimated to be ~100 nm by light scattering experiment and transmission electron microscopy. Recognition of HA on the VLP surface by the HA2-specific monoclonal antibody IIF4 at acidic pH, as probed by surface plasmon resonance, indicated the pH-induced structural rearrangement of HA. Uptake of the particle by A549 mediated by HA-sialylose receptor interaction was visualized by the fluorescent-labeled VLP. The HA-promoted cell-virus fusion activity was illustrated by fluorescence imaging on the Jurkat cells incubated with rhodamine-loaded VLP performed at fusogenic pH. Furthermore, the green fluorescence protein (GFP) was fused to NA to produce VLP with a pH-sensitive probe, expanding the use of VLP as an antigen carrier and a tool for viral tracking.
The Differential Expression of Aqueous Soluble Proteins in Breast Normal and Cancerous Tissues in Relation to Stage and Grade of Patients
Authors: Liang Seng , Singh Manjit , Gam Lay-Harn
Published: December 2010

Breast cancer is a leading cause of female deaths worldwide. In Malaysia, it is the most common form of female cancer while Infiltrating ductal carcinoma (IDC) is the most common form of breast cancer. A proteomic approach was used to identify changes in the protein profile of breast cancerous and normal tissues. The patients were divided into different cohorts according to tumour stage and grade. We identified twenty-four differentially expressed hydrophilic proteins. A few proteins were found significantly related to various stages and grades of IDC, amongst which were SEC13-like 1 (isoform b), calreticulin, 14-3-3 protein zeta, and 14-3-3 protein eta. In this study, we found that by defining the expression of the proteins according to stages and grades of IDC, a significant relationship between the expression of the proteins with the stage or grade of IDC can be established, which increases the usefulness of these proteins as biomarkers for IDC.
Metalloproteinase Inhibitors: Status and Scope from Marine Organisms
Authors: Thomas Noel Vinay , Kim Se-Kwon
Published: December 2010

Marine environment has been the source of diverse life forms that produce different biologically active compounds. Marine organisms are consistently contributing with unparalleled bioactive compounds that have profound applications in nutraceuticals, cosmeceuticals, and pharmaceuticals. In this process, screening of natural products from marine organisms that could potentially inhibit the expression of metalloproteinases has gained a huge popularity, which became a hot field of research in life sciences. Metalloproteinases, especially, matrix metalloproteinases (MMPs) are a class of structurally similar enzymes that contribute to the extracellular matrix degradation and play major role in normal and pathological tissue remodeling. Imbalance in the expression of MMPs leads to severe pathological condition that could initiate cardiac, cartilage, and cancer-related diseases. Three decades of endeavor for designing potent matrix metalloproteinase inhibitory substances (MMPIs) with many not making upto final clinical trials seek new resources for devising MMPIs. Umpteen number of medicinally valuable compounds being reported from marine organisms, which encourage current researchers to screen potent MMPIs from marine organisms. In this paper, we have made an attempt to report the metalloproteinase inhibiting substances from various marine organisms.
Genome Size Variation in Malus Species (Erratum)
Authors: Höfer Monika , Meister Armin
Published: December 2010

The sectional classification of the genus Malus should correctly read Eumalus (Malus).
Smoothing and Regularization with Modified Sparse Approximate Inverses
Authors: Huckle T. , Sedlacek M.
Published: December 2010

Sparse approximate inverses M which satisfy minM∥AM−I∥F
have shown to be an attractive alternative to classical
smoothers like Jacobi or Gauss‐Seidel (Tang and Wan; 2000).
The static and dynamic computation of a SAI and a SPAI
(Grote and Huckle; 1997), respectively, comes along with advantages like
inherent parallelism and robustness with equal smoothing
properties (Bröker et al.; 2001). Here, we are interested in
developing preconditioners that can incorporate probing conditions
for improving the approximation relative to high‐ or low‐frequency
subspaces. We present analytically derived optimal smoothers for
the discretization of the constant‐coefficient Laplace operator.
On this basis, we introduce probing conditions in the
generalized Modified SPAI (MSPAI) approach (Huckle and Kallischko; 2007)
which yields efficient smoothers for multigrid. In the second
part, we transfer our approach to the domain of ill‐posed problems to
recover original information from blurred signals. Using the probing
facility of MSPAI, we impose the preconditioner to act as
approximately zero on the noise subspace. In combination with an
iterative regularization method, it thus becomes possible to
reconstruct the original information more accurately in many cases.
A variety of numerical results demonstrate the usefulness of this approach.
Ecosystem-Scale Effects of Nutrients and Fishing on Coral Reefs
Authors: Walsh Sheila M.
Published: December 2010

Nutrient pollution and fishing are the primary local causes of coral reef decline but their ecosystem-scale effects are poorly understood. Results from small-scale manipulative experiments of herbivores and nutrients suggest prioritizing management of fishing over nutrient pollution because herbivores can control macroalgae and turf in the presence of nutrients. However, ecological theory suggests that the opposite occurs at large scales. Moreover, it is unclear whether fishing decreases herbivores because fishing of predators may result in an increase in herbivores. To investigate this paradox, data on the fish and benthic communities, fishing, and nutrients were collected on Kiritimati, Kiribati. Oceanographic conditions and a population resettlement program created a natural experiment to compare sites with different levels of fishing and nutrients. Contrary to theory, herbivores controlled macroalgae in the presence of nutrients at large spatial scales, and herbivores had greater effects on macroalgae when nutrients were higher. In addition, fishing did not increase herbivores. These results suggest that protecting herbivores may have greater relative benefits than reducing nutrient pollution, especially on polluted reefs. Reallocating fishing effort from herbivores to invertivores or planktivores may be one way to protect herbivores and indirectly maintain coral dominance on reefs impacted by fishing and nutrient pollution.
Bronchoscopic Lung Volume Reduction
Authors: Ernst Armin , Anantham Devanand
Published: December 2010

The application of lung volume reduction surgery in clinical practice is limited by high postoperative morbidity and stringent selection criteria. This has been the impetus for the development of bronchoscopic approaches to lung volume reduction. A range of different techniques such as endobronchial blockers, airway bypass, endobronchial valves, thermal vapor ablation, biological sealants, and airway implants have been employed on both homogeneous as well as heterogeneous emphysema. The currently available data on efficacy of bronchoscopic lung volume reduction are not conclusive and subjective benefit in dyspnoea scores is a more frequent finding than improvements on spirometry or exercise tolerance. Safety data are more promising with rare procedure-related mortality, few serious complications, and short hospital length of stay. The field of bronchoscopic lung volume reduction continues to evolve as ongoing prospective randomized trials build on earlier feasibility data to clarify the true efficacy of such techniques.
Exact Solution of Impulse Response to a Class of Fractional Oscillators and Its Stability
Authors: Li Ming , Lim S. C. , Chen Shengyong
Published: December 2010

Oscillator of single‐degree‐freedom is a typical model in system analysis. Oscillations resulted from differential equations with fractional order attract the interests of researchers since such a type of oscillations may appear dramatic behaviors in system responses. However, a solution to the impulse response of a class of fractional oscillators studied in this paper remains unknown in the field. In this paper, we propose the solution in the closed form to the impulse response of the class of fractional oscillators. Based on it, we reveal the stability behavior of this class of fractional oscillators as follows. A fractional oscillator in this class may be strictly stable, nonstable, or marginally stable, depending on the ranges of its fractional order.
Commutative Pseudo valuations on BCK‐Algebras
Authors: Doh Myung Im , Kang Min Su
Published: December 2010

The notion of a commutative pseudo valuation on a BCK‐algebra is introduced, and its characterizations are investigated. The relationship between a pseudo valuation and a commutative pseudo‐valuation is examined.
Mutation of Herpesvirus Saimiri ORF51 Glycoprotein Specifically Targets Infectivity to Hepatocellular Carcinoma Cell Lines
Authors: Turrell Susan J. , Whitehouse Adrian
Published: December 2010

Herpesvirus saimiri (HVS) is a gamma herpesvirus with several properties that make it an amenable gene therapy vector; namely its large packaging capacity, its ability to persist as a nonintegrated episome, and its ability to infect numerous human cell types. We used RecA‐mediated recombination to develop an HVS vector with a mutated virion protein. The heparan sulphate‐binding region of HVS ORF51 was substituted for a peptide sequence which interacts with somatostatin receptors (SSTRs), overexpressed on hepatocellular carcinoma (HCC) cells. HVS mORF51 showed reduced infectivity in non‐HCC human cell lines compared to wild‐type virus. Strikingly, HVS mORF51 retained its ability to infect HCC cell lines efficiently. However, neutralisation assays suggest that HVS mORF51 has no enhanced binding to SSTRs. Therefore, mutation of the ORF51 glycoprotein has specifically targeted HVS to HCC cell lines by reducing the infectivity of other cell types; however, the mechanism for this targeting is unknown.
Deformation Calculating of Electromagnetic Launcher′s Rail Subjected to Sinusoidal Magnetic Pressure
Authors: Wen Liu , Lei Shi , Xiangzhong Bai
Published: December 2010

The electromagnetic launcher′s rail can be modeled as a beam on elastic foundation with simply supported beam by moving load. In this paper, Euler beam theory is applied to build the mechanical model, and the analytical solution of the equation subjected to sinusoidal magnetic pressure is derived in detail, which has successfully avoided the errors which are caused by using the uniform pressure to approximately replace the variable force. Numerical analysis of the influences brought from the elastic coefficient, the damping coefficient, the mass of rail, and the load′s velocity on the deformation of beam by the MATLAB software show that the elastic coefficient and the load′s velocity have quite obvious effect on the deformation of the beam while the damping coefficient and the mass of rail have not obvious effect on the deformation of the beam.
Three-Dimensional Collagen I Promotes Gemcitabine Resistance in Pancreatic Cancer through MT1-MMP–Mediated Expression of HMGA2
Authors: Dangi-Garimella Surabhi , Krantz Seth B. , Barron Morgan R. , Shields Mario A. , Heiferman Michael J. , Grippo Paul J. , Bentrem David J. , Munshi Hidayatullah G.
Published: December 2010

One of the hallmarks of human pancreatic ductal adenocarcinoma (PDAC) is its pronounced type I collagen-rich fibrotic reaction. Although recent reports have shown that the fibrotic reaction can limit the efficacy of gemcitabine chemotherapy, the underlying mechanisms remain poorly understood. In this article, we show that the type I collagen allows PDAC cells to override checkpoint arrest induced by gemcitabine. Relative to cells grown on tissue culture plastic, PDAC cells grown in 3-dimensional collagen microenvironment have minimal Chk1 phosphorylation and continue to proliferate in the presence of gemcitabine. Collagen increases membrane type 1 matrix metalloproteinase (MT1-MMP)–dependent ERK1/2 phosphorylation to limit the effect of gemcitabine. Collagen also increases MT1-MMP–dependent high mobility group A2 (HMGA2) expression, a nonhistone DNA-binding nuclear protein involved in chromatin remodeling and gene transcription, to attenuate the effect of gemcitabine. Overexpression of MT1-MMP in the collagen microenvironment increases ERK1/2 phosphorylation and HMGA2 expression, and thereby further attenuates gemcitabine-induced checkpoint arrest. MT1-MMP also allows PDAC cells to continue to proliferate in the presence of gemcitabine in a xenograft mouse model. Clinically, human tumors with increased MT1-MMP show increased HMGA2 expression. Overall, our data show that collagen upregulation of MT1-MMP contributes to gemcitabine resistance in vitro and in a xenograft mouse model, and suggest that targeting MT1-MMP could be a novel approach to sensitize pancreatic tumors to gemcitabine. Cancer Res; 71(3); 1019–28. ©2010 AACR.
Human Papillomavirus E7 Enhances Hypoxia-Inducible Factor 1–Mediated Transcription by Inhibiting Binding of Histone Deacetylases
Authors: Bodily Jason M. , Mehta Kavi P.M. , Laimins Laimonis A.
Published: December 2010

Infection by human papillomaviruses (HPV) leads to the formation of benign lesions, warts, and in some cases, cervical cancer. The formation of these lesions is dependent upon increased expression of proangiogenic factors. Angiogenesis is linked to tissue hypoxia through the activity of the oxygen-sensitive hypoxia-inducible factor 1α (HIF-1α). Our studies indicate that the HPV E7 protein enhances HIF-1 transcriptional activity whereas E6 functions to counteract the repressive effects of p53. Both high- and low-risk HPV E7 proteins were found to bind to HIF-1α through a domain located in the N-terminus. Importantly, the ability of E7 to enhance HIF-1 activity mapped to the C-terminus and correlated with the displacement of the histone deacetylases HDAC1, HDAC4, and HDAC7 from HIF-1α by E7. Our findings describe a novel role of the E7 oncoprotein in activating the function of a key transcription factor mediating hypoxic responses by blocking the binding of HDACs. Cancer Res; 71(3); 1187–95. ©2010 AACR.
Data Assimilation of Cloud-Affected Radiances in a Cloud-Resolving Model
Authors: Polkinghorne Rosanne , Vukicevic Tomislava
Published: December 2010

Assimilation of cloud-affected infrared radiances from the Geostationary Operational Environmental Satellite-8 (GOES-8) is performed using a four-dimensional variational data assimilation (4DVAR) system designated as the Regional Atmospheric Modeling Data Assimilation System (RAMDAS). A cloud mask is introduced in order to limit the assimilation to points that have the same type of cloud in the model and observations, increasing the linearity of the minimization problem. A series of experiments is performed to determine the sensitivity of the assimilation to factors such as the maximum-allowed residual in the assimilation, the magnitude of the background error decorrelation length for water variables, the length of the assimilation window, and the inclusion of other data such as ground-based data including data from the Atmospheric Emitted Radiance Interferometer (AERI), a microwave radiometer, radiosonde, and cloud radar. In addition, visible and near-infrared satellite data are included in a separate experiment. The assimilation results are validated using independent ground-based data. The introduction of the cloud mask where large residuals are allowed has the greatest positive impact on the assimilation. Extending the length of the assimilation window in conjunction with the use of the cloud mask results in a better-conditioned minimization, as well as a smoother response of the model state to the assimilation.
Reduced Human Beta Defensin 3 in Individuals with Periodontal Disease
Authors: Brancatisano F.L. , Maisetta G. , Barsotti F. , Esin S. , Miceli M. , Gabriele M. , Giuca M.R. , Campa M. , Batoni G.
Published: December 2010

The human beta defensin 3 (hBD3) is widely expressed in the oral cavity and exerts strong antibacterial and immunomodulatory activities. Hence, we hypothesized that hBD3 could play a protective role in the maintenance of periodontal homeostasis, and that it could be found in gingival crevicular fluid (GCF) of healthy individuals and those with periodontitis at levels correlating with the degree of periodontal health. By using an ELISA assay to quantify hBD3 in GCF, we demonstrated that the peptide is present at levels easily detectable in the majority of healthy individuals, but it is drastically reduced in GCF from those with periodontitis. Furthermore, hBD3 levels inversely correlate with the severity of the disease and the degree of colonization by combinations of bacterial species with elevated periodontopathogenic potential. Both genetic factors and host/bacterial proteases released in diseased sites may be responsible for the observed low/null hBD3 levels in GCF from individuals with periodontitis.
Continuing Education Course #1
Authors: Peterson Richard A. , Gabrielson Kathy L. , Allan Johnson G. , Pomper Martin G. , Coatney Robert W. , Winkelmann Christopher T.
Published: December 2010

The continuing education course “Non-Invasive Imaging as a Problem-Solving Tool and Translational Biomarker Strategy in Toxicologic Pathology” provided a thorough overview of commonly used imaging modalities and the logistics required for integration of small animal imaging into toxicologic pathology. Non-invasive imaging (NIN) is gaining acceptance as an important modality in toxicologic pathology. This technology allows nonterminal, time-course evaluation of functional and morphologic endpoints and can be used to translate biomarkers between preclinical animal models and human patients. NIN can support drug development as well as basic research in academic or industrial environments. An initial overview of theoretical principles was followed by focused presentations on magnetic resonance imaging (MRI)/magnetic resonance microscopy (MRM), positron emission tomography (PET)/single proton emission computed tomography (SPECT), ultrasonography (US, primarily focused on echocardiography), optical (bioluminescent) imaging, and computed tomography (CT). The choice of imaging modality will depend on the research question and the needed resolution.
Gender differences in brain serotonin transporter availability in panic disorder
Authors: Maron Eduard , Tõru Innar , Hirvonen Jussi , Tuominen Lauri , Lumme Ville , Vasar Veiko , Shlik Jakov , Nutt David J , Helin Semi , Någren Kjell , Tiihonen Jari , Hietala Jarmo
Published: December 2010

The role of the serotonin (5-HT) system in the neurobiology and treatment of panic disorder (PD) remains unproven. Previously we detected lower brain 5-HT transporter (SERT) availability in PD, but the findings were preliminary and mainly limited to female patients. The aim of this study was to assess non-displaceable brain SERT binding potential ( BPND) in male and female patients with PD. The SERT BPND was measured in groups of patients with PD (five males and six females) and matched healthy control subjects (12 males and 12 females) using positron emission tomography (PET) and [11C]MADAM tracer. SERT BPND were significantly higher in 13 of 20 studied brain regions, including several cortical and raphe areas, but lower in the hippocampus in males with PD as compared with healthy males. No significant differences in SERT BPND were observed between female patients and controls. The results suggest gender-dependent regional differences in brain SERT availability and converge with previous PET findings of reduced 5-HT1A receptor binding in similar brain areas in PD. Distinctive functioning of the 5-HT system in males and females may underlie certain gender-dependent differences in expressions of PD.
Novel object recognition memory: measurement issues and effects of MDMA self-administration following short inter-trial intervals
Authors: Schenk Susan , Harper David N , Do Jennifer
Published: December 2010

The present study was undertaken to examine effects of self-administered MDMA on novel object exploration (NOR) memory. Self-administration was conducted during daily 2 h tests that continued until a total of 165 mg/kg was self-administered (range = 13–41 days for individual rats). Control rats were placed in the self-administration boxes during daily sessions but did not receive any drug. One or 10 weeks following the last self-administration session, memory was assessed using a standard NOR task. When exploration time was used as the dependent measure for the control rats, there was no consistent pattern of change as a function of inter-trial interval (ITI) and exploration times failed to reveal decay in the function relating exploration to ITI. When number of approaches was examined as a function of ITI, however, there was a preference for the novel object following the short ITIs (1–15 min) and the function relating preference to ITI decayed with longer ITIs. When tested 7 days following the last self-administration session, rats that self-administered MDMA failed to demonstrate NOR even following the shortest ITI of 1 min. The data support the idea that MDMA self-administration produces cognitive deficits and are consistent with the idea that attentional processes become disrupted. There was, however, recovery of NOR memory when rats were tested following an extended drug-free period of 70 days. Thus, the deficits are transient and recovery was apparent.
Sumatriptan as a treatment for cyclic vomiting syndrome: A clinical trial
Authors: Hikita Toshiyuki , Kodama Hiroko , Kaneko Sono , Amakata Kaori , Ogita Kaori , Mochizuki Daishi , Kaga Fumiaya , Nakamoto Natsue , Fujii Yasushi , Kikuchi Akira
Published: December 2010

Background and objective

Cyclic vomiting syndrome (CVS) is associated with migraine. This study aimed to evaluate the efficacy of sumatriptan in treating CVS.

Methods

Twelve patients were enrolled in this trial. Sumatriptan was administered either subcutaneously [(age × 4 + 20)/100×3mg] or by nasal spray (NS; 20 mg). Response to the treatment was classified as complete, effective, or noneffective.

Results

Eleven patients, who presented with 35 attacks, were treated by subcutaneous injection of sumatriptan. The treatment was responsive in 19 attacks. The efficacy of sumatriptan was high in attacks that occurred in cases with a family history of migraine compared to those without (p = .0482). Five patients were treated with sumatriptan NS for six attacks. The treatment was completely responsive in two of six attacks. We observed no adverse effects associated with sumatriptan treatment in this trial.

Conclusions

We conclude that sumatriptan has potential efficacy in treating of patients with CVS.
Book Reviews: Equity and Gender: The Comparable Worth Debate
Authors: Crosby Faye
Published: December 2010

Ellen Frankel Paul. New Brunswick: Transaction Publishers, 1989. 143 pp. $24.95 (cloth), $12.95 (paper)
The Resume Characteristics Determining Job Interviews for Middle-Aged Women Seeking Entry-Level Employment
Authors: Johnson Emily , Lahey Joanna
Published: December 2010

Obtaining an entry-level job can be critically important for women with little education, particularly those who have taken time out of the labor force. This article uses archival data from a field experiment, called a resume audit study, to examine the characteristics of entry-level resumes that are important to potential employers. In accordance with earlier theory, post–high school education and training, such as from a community college or a computer training program, are primary factors in determining whether a woman receives an interview. For example, vocational training more than doubles the chance of an interview. Other factors are not as important for entry-level jobs, unlike what resume manuals aimed at college graduates suggest.
Effects of a Group Intervention on the Career Network Ties of Finnish Adolescents
Authors: Jokisaari Markku , Vuori Jukka
Published: December 2010

The authors evaluated how a group-based career intervention affected career network ties among Finnish adolescents as they made educational choices and prepared for their transition to secondary education. They examined the career-related network ties of 868 students during their last year in comprehensive school (junior high school) in a randomized field experimental study. The results indicated that immediately after the intervention, the group method lowered the density of participants' career networks, that is, the participants' network ties were less interconnected. The results further showed that about 6 months after the intervention, the program had increased the number of school counselors named as network ties.
Adapting an Evidence-Based Reading Comprehension Strategy for Learners With Autism Spectrum Disorder
Authors: Whalon Kelly , Hart Juliet E.
Published: December 2010

Reading is a critical skill for student success in school and postschool opportunities. Although a number of children with autism spectrum disorder (ASD) will develop the decoding skills necessary to read text, many will continue to struggle with reading comprehension. No Child Left Behind (NCLB) and the Individuals with Disabilities Education Improvement Act (IDEIA) mandated that all children receive evidence-based reading instruction consistent with the National Reading Panel (NRP) recommendations. Beginning evidence suggests that children with ASD can benefit from instruction consistent with the NRP recommendations. This article illustrates how to implement question-and-answer relationships (QAR), a specific NRP-advocated strategy, using research-based instructional supports found responsive in meeting the learning needs of students with ASD.
The (AAT)n repeat of the cannabinoid CB1 receptor gene influences disease progression in relapsing multiple sclerosis
Authors: Rossi Silvia , Buttari Fabio , Studer Valeria , Motta Caterina , Gravina Paolo , Castelli Maura , Mantovani Vilma , De Chiara Valentina , Musella Alessandra , Fiore Stefania , Masini Silvia , Bernardi Giorgio , Maccarrone Mauro , Bernardini Sergio , Centonze Diego
Published: December 2010

Background: Genetic and pharmacological inactivation of cannabinoid CB1 receptors (CB1Rs) exacerbates disease course in experimental autoimmune encephalomyelitis, suggesting that CB1Rs might play a role in the neurodegenerative damage associated with multiple sclerosis (MS).

Objectives: To see whether CNR1 gene polymorphism could influence disease progression in relapsing–remitting MS.

Methods: The genotype of 350 patients for the number of AAT repeats was characterized and correlation studies were performed with measures of disease severity and progression.

Results: MS patients with the homozygous genotype for long AAT repeats in the CNR1 gene had more severe disease and higher risk of progression. These subjects had significantly higher scores on both the progression index and the MS severity scale. Furthermore, the percentage of patients with MS functional composite score progression or Bayesian Risk Estimate for MS (BREMS) score ≥2 (considered at very high risk of secondary progression) was significantly higher in the AAT long group than in the short group, while the frequency of patients with BREMS score ≤−0.63 (very likely to remain progression-free) was not significantly different between the two groups, although lower in the long group. Finally, the frequency of patients prescribed a second-line treatment was significantly higher among subjects of the AAT long group, providing a further, indirect indication of higher disease severity.

Conclusions: The results of the present investigation point to CB1R as an important modulator of disease severity in relapsing MS subjects.
Elimination of Deleterious Effects of DMBA-Induced Skin Carcinogenesis in Mice by Syzygium cumini Seed Extract
Authors: Parmar Jyoti , Sharma Priyanka , Verma Preeti , Sharma Priyanka , Goyal Pradeep K.
Published: December 2010

The inhibition of tumor incidence by hydro-alcoholic extract of S.cumini seed was evaluated in mice on two stage process of skin carcinogenesis induced by single application of 7, 12-dimethyl benz(a)anthracene (100 µg/100µl of acetone), and 2 weeks later promoted by repeated application of croton oil (1% acetone/thrice in a week) till the end of the experiment (i.e. 16 weeks). Oral administration of extract at a dose of 250mg/kg b.wt./day at the peri-initiational stage (i.e. 7 days before and 7 days after DMBA application), promotional stage (i.e. from the time of croton oil application) and at both the stages (i.e. 7 days prior to DMBA application & continued till the end of experiment) to the mice, recorded a significant reduction in tumor incidence to 37.5, 50 & 25% respectively in comparison to the carcinogen treated control, where tumor incidence was found as 100%. Tumor yield and Tumor burden were also significantly reduced by SCE. Similarly, the cumulative number of papillomas after 16 weeks was 68 in the control group, which was reduced to 15, 21 & 8 in the animals treated with the SCE continuously at peri-, post- and peri- & post- initiation stage respectively. A significant impairment was noticed in the levels of reduced glutathione, superoxide dismutase, catalase & protein and enhancement in LPO in liver and skin of carcinogen treated control mice as compared with vehicle treated mice. All such parameters were returned to near normal value by administration of SCE to DMBA treated mice. These results suggest a possible chemopreventive property of S.cumini against DMBA induced skin carcinogenesis in mice.
Antineoplastic Effects of Bee Honey and Nigella sativa on Hepatocellular Carcinoma Cells
Authors: Hassan Mahmoud I. , Mabrouk Gamal M. , Shehata Hanan H. , Aboelhussein Marwa M.
Published: December 2010

Objectives: To evaluate in vitro antitumor effects of bee honey (BH) and Nigella sativa (NS) on HepG2 through their antioxidant and apoptotic activities. Methods: HepG2 cell line was treated with different concentrations of diluted unfractionated BH and different concentrations of alcohol extract of NS. Exposure lasted for different time durations (6-72 hours), both dose–response and time course–response were conducted. Cell viability was tested by trypan blue exclusion test. Total antioxidant status and caspase-3 activity were estimated in the cell lysate. Nitric oxide levels were measured in culture supernatants of both treated and untreated HepG2 at all indicated times. Results: Treatment of HepG2 cells with BH and NS leads to a significant decrease in both the number of viable HepG2 cells and the levels of nitric oxide on one hand, but improvement of the total antioxidant status and caspase-3 activity on the other, especially in HepG2 cells treated with higher doses of BH and NS (20% and 5000 μg/mL, respectively) and for longer duration (72 hours). Conclusions: BH and NS are effective in reducing the viability of HepG2 cells, improving their antioxidant status and inducing their apoptotic death.