bluuebunny/crossref_metadata_2025 huggingface dataset:
Phylogenetic clustering increases with elevation for microbes
Authors: Wang Jianjun , Soininen Janne , He Jizheng , Shen Ji
Published: January 2012

Although phylogenetic approaches are useful for providing insights into the processes underlying biodiversity patterns, the studies of microbial phylogenetic relatedness are rare, especially for elevational gradients. Using high‐throughput pyrosequencing, we examined the biodiversity patterns for biofilm bacterial communities that were scraped from stream stones along an elevational gradient from 1820 to 4050 m in China. The patterns of bacterial species richness and phylogenetic diversity were hollow towards higher elevations. The bacterial communities consisted of closer relatives than expected and displayed increasing terminal phylogenetic clustering towards mountain top. The increasing phylogenetic clustering with elevation contrasts reports for macroorganisms that revealed phylogenetic overdispersion at low or intermediate elevations. Because water temperature showed the strongest correlation with phylogenetic relatedness (r2 = 0.516), the elevational pattern in the bacterial phylogenetic structure indicated that environmental filtering possibly due to lower temperature or more frequent temperature fluctuations increased towards higher elevations. Evidence supporting the environmental filtering on bacteria was also reflected by the orderly succession in the relative abundance of different bacterial phyla along the elevational gradient and in the high evenness of bacterial taxa at higher elevations. Overall, our results indicated that ecological processes possibly related to temperature may play a dominant role in structuring bacterial biodiversity along the elevational gradient.
p24 proteins, intracellular trafficking, and behavior: Drosophila melanogaster provides insights and opportunities
Authors: Carney Ginger E. , Bowen Nathan J.
Published: January 2012

Summry— The p24 transmembrane proteins, also known as EMP24/GP25 (endomembrane protein precursor of 24kD (Schimmoller et al., 1995) proteins, are components of coat protein (COP)‐coated vesicles and are present in species as diverse as fungi, plants, flies, worms, and mammals, indicating that they have important conserved functions. Genetic, molecular, and biochemical characterization of these proteins and the loci that encode them has provided insights into their potential cellular roles, including postulated functions in vesicle cargo protein selection and sorting, COPI and COPII vesicle formation and budding, and quality control of proteins that mature through the secretory pathway. Recently, the first mutations in a Drosophila melanogaster p24 gene have been isolated and characterized. These alleles produce an interesting behavioral phenotype in females, affecting their ability to oviposit. This identification and mutant characterization of a p24 locus in Drosophila will pave the way for a better understanding of cell‐type‐specific functions and interactions among p24 proteins.
Characterization of tissue specific expression of Notch‐1 in human tissues
Authors: Baldi Alfonso , De Falco Maria , De Luca Luca , Cottone Giuliano , Paggi Marco G. , Nickoloff Brian J. , Miele Lucio , De Luca Antonio
Published: January 2012

Summry— Signaling through the Notch cell surface receptors is a highly conserved mechanism of cell fate specification. Notch signaling regulates proliferation, differentiation and cell death. In vertebrates, putative gene duplication has originated four Notch genes, Notch‐1, −2, −3 and −4. They have been implicated in neurogenesis, hematopoiesis, T‐cell development, vasculogenesis and brain cortical growth. We have investigated Notch‐1 distribution in normal human tissues by immunohistochemistry and immunoblot. We detected widespread expression of Notch‐1 cytoplasmatic staining, with different tissue distributions in the different organs examined. In particular, high expression of Notch‐1 was detected in the intermediate suprabasal layers, but not in the dead cells at the extreme periphery of stratified epithelia. Moreover, a low/intermediate level of Notch‐1 was observed in lymphocytes in several peripheral lymphoid tissues; in particular the germinal centers of lymph nodes showed the most abundant number of positive cells, which appeared to be centroblasts/immunoblasts based on nuclear morphology. Notch‐1 participates in keratinocytes differentiation. We showed by Western blot analysis that Notch‐1 level was clearly increased in HaCaT cells after Ca++ addition and remained substantially elevated until late differentiation stages. These results suggest that Notch‐1 may function in numerous cell types in processes beyond cell fate determination, such as neuronal plasticity, muscle hypertrophy, liver regeneration, and germinal center lymphopoiesis during the immune response.
Gel‐to‐gel phase transition may occur in mammalian cells: Mechanism of formation of “dark” (compacted) neurons
Authors: Gallyas Ferenc , Farkas Orsolya , Mázló Mária
Published: January 2012

Summry— In the course of many diseases, individual non‐apoptotic cells that are randomly distributed among undamaged cells in various mammalian tissues become shrunken and hyperbasophilic (“dark”). The light microscopic shrinkage is caused by a potentially reversible, dramatic compaction of all ultrastructural elements inside the affected cells, and escape of the excess water through apparently intact plasma membrane. In the case of neurons, the ultrastructural compaction rapidly involves the soma‐dendrite domains in an all‐or‐nothing manner, and also mm‐long axon segments. The present paper demonstrates that such ultrastructural compaction in neurons, which affects the whole soma‐dendrite domain or long axon segments, can take place both immediately after an in vivo head injury and in rat brains perfusion‐fixed for 30 min., and then chilled to just above the freezing point before the same kind of head injury was inflicted. This argues strongly against any enzyme‐mediated compaction mechanism. On the analogy of gel‐to‐gel phase transitions in polymer chemistry, we hypothesize a pure physico‐chemical compaction mechanism. Specifically, after initiation at a single site in each affected cell, the ultrastructural compaction is propelled throughout the whole cell on the domino principle by the free energy stored in the form of non‐covalent interactions among the constituents of some cytoplasmic gel structure.
The activation mechanism of class‐C G‐protein coupled receptors
Authors: Pin J.‐P , Kniazeff J , Goudet C , Bessis A.‐S , Liu J , Galvez T , Acher F , Rondard P , Prézeau L
Published: January 2012

Summry— Class‐C G‐protein coupled receptors (GPCRs) represent a distant group among the large family of GPCRs. This class includes the receptors for the main neurotransmitters, glutamate and γ‐aminobutyric acid (GABA), and the receptors for Ca2+, some taste and pheromone molecules, as well as some orphan receptors. Like any other GPCRs, class‐C receptors possess a heptahelical domain (HD) involved in heterotrimeric G‐protein activation, but most of them also have a large extracellular domain (ECD) responsible for agonist recognition and binding. In addition, it is now well accepted that these receptors are dimers, either homo or heterodimers. This complex architecture raises a number of important questions. Here we will discuss our view of how agonist binding within the large ECD triggers the necessary change of conformation, or stabilize a specific conformation, of the heptahelical domain leading to G‐protein activation. How ligands acting within the heptahelical domain can change the properties of these complex macromolecules.
AGS proteins, GPR motifs and the signals processed by heterotrimeric G proteins
Authors: Lanier Stephen M
Published: January 2012

Summry— A long term objective of our research effort is to define factors that influence the specificity and efficiency of signal propagation by heterotrimeric G‐proteins (G). G‐proteins play a central role in cellular communication mediating the cell response to numerous hormones and neurotransmitters. A major determinant of signalling specificity for heterotrimeric G‐proteins is the cell specific expression of the subtypes of the primary signalling entities, receptor, G and effector (E). Another major site for regulating signalling specificity lies at the R‐G or G‐E interface where these interactions are influenced by cell architecture, the stoichiometry of signalling components and accessory proteins that may segregate the receptor to microdomains of the cell, regulate the efficiency and/or specificity of signal transfer and/or influence the activation state of G‐protein independent of a classical G‐protein coupled receptor. One strategy to address these issues in our laboratory involves the identification of cellular proteins that regulate the transfer of signal from receptor to G or directly influence the activation state of G independent of a classical G‐protein coupled receptor. We identified three proteins, AGS1, AGS2 and AGS3 (for Activators of G‐protein Signaling), that activated heterotrimeric G‐protein signalling pathways in the absence of a typical receptor. AGS1, 2 and 3 interact with different subunits and/or conformations of heterotrimeric G‐proteins, selectively activate different G‐proteins, provide unexpected mechanisms for regulation of the G‐protein activation cycle and have opened up a new area of research related to the cellular role of G‐proteins as signal transducers.
Delineation of the conserved functional properties of D1A, D1B and D1C dopamine receptor subtypes in vertebrates
Authors: Le Crom Stéphane , Sugamori Kim S , Sidhu Anita , Niznik Hyman B , Vernier Philippe
Published: January 2012

Summry— The three main subtypes of dopamine D1 receptor (D1A, D1B and D1C) subtypes found in most vertebrate groups were generated by two major steps of gene duplications, early in evolution. To identify the functional characteristics contributing to conservation of these paralogous D1 receptors in vertebrates, the pharmacological and functional properties of fish (Anguilla anguilla), amphibian (Xenopus lævis) and human receptors were systematically analysed in transfected cells. The ligand‐binding parameters appeared essentially similar for orthologous receptors, but differed significantly among the subtypes. The D1A receptors from the three species displayed low intrinsic activity and a fast rate of agonist‐induced desensitization. All the orthologous D1B receptors exhibited a similar desensitization time‐course, but with smaller amplitude of decrease than D1A receptors, in agreement with their higher basal activity. In contrast, D1C receptors, which do not exist in mammals, have low intrinsic activity and exhibit only weak, but rapid, agonist‐induced desensitization, without any changes upon longer treatment with agonist. Thus, each of the three D1 receptor subtypes are characterized by activation and desensitization properties, in a sequence‐specific manner, which has been probably acquired early after gene duplications, and constrained their conservation during vertebrate evolution. These properties have been instrumental to adapt dopamine system to the physiology of the numerous neuronal networks and functions they control in the large and complex brains of vertebrates.
USING SAT-BASED TECHNIQUES IN LOW POWER STATE ASSIGNMENT
Authors: SAGAHYROON ASSIM , ALOUL FADI A. , SUDNITSON ALEXANDER
Published: January 2012

Power consumption of synchronous sequential circuits can be reduced by careful encoding of the states of the circuit. The idea is to reduce the average number of bit changes per state transition by finding an optimal state assignment. This state assignment problem is NP-hard, and existing techniques rely mainly on heuristic-based methods. The primary goal of this work is to assess the suitability of using complete advanced Boolean Satisfiability and Integer Linear Programming (ILP) methods in finding an optimized solution. We formulate the problem as a 0-1 ILP instance with power minimization being the objective. Using generic and commercial solvers, the proposed approach was tested on sample circuits from the MCNC benchmark suite. Furthermore, in an effort to accelerate the search process, circuits were checked for symmetries and symmetry breaking predicates were added whenever applicable. The experimental results provide a pragmatic insight into the problem and basis for further exploration.
MODELING GATE CURRENT FOR NANO SCALE MOSFET WITH DIFFERENT GATE SPACER
Authors: RANA ASHWANI K. , CHAND NAROTTAM , KAPOOR VINOD
Published: January 2012

Dimensions of metal–oxide–semiconductor field effect transistor (MOSFET) have been scaled down for decades to maintain the performance. So, as a result of aggressive scaling, gate oxide thickness approaches its manufacturing and physically limiting value of less than 2 nm in nano regime. Under such circumstances, gate leakage (tunneling) current has become a critical problem in nano domain as compared to subthreshold leakage current. Consequently, accurate quantitative understanding of gate tunneling leakage current is very important especially in context of low power VLSI application. In this work, gate tunneling currents have been modeled including the inevitable nano scale effects for a MOSFET having different high-k dielectric spacer such as SiO2 , Si3N4 , Al2O3 , HfO2 . The gate current model is compared and contrasted with santaurus simulation results and reported experimental result to verify the accuracy of the model. The agreement found was good, thus validating the developed analytical model. It is observed that neglecting nano scale effects may lead to large error in the calculated gate current. It is found in the results that gate leakage current decreases with the increase of dielectric constant of the gate spacer. Further, it is also reported that the spacer materials impact the threshold voltage, on current, off current, drain induced barrier lowering, and subthreshold slope of the device.
A DELAY-DEPENDENT APPROACH TO ROBUST TAKAGI–SUGENO FUZZY CONTROL OF UNCERTAIN RECURRENT NEURAL NETWORKS WITH MIXED INTERVAL TIME-VARYING DELAYS
Authors: TSENG K. H. , TSAI J. S. H. , LU C. Y.
Published: January 2012

This paper deals with the problem of globally delay-dependent robust stabilization for Takagi–Sugeno (T–S) fuzzy neural network with time delays and uncertain parameters. The time delays comprise discrete and distributed interval time-varying delays and the uncertain parameters are norm-bounded. Based on Lyapunov–Krasovskii functional approach and linear matrix inequality technique, delay-dependent sufficient conditions are derived for ensuring the exponential stability for the closed-loop fuzzy control system. An important feature of the result is that all the stability conditions are dependent on the upper and lower bounds of the delays, which is made possible by using the proposed techniques for achieving delay dependence. Another feature of the results lies in that involves fewer matrix variables. Two illustrative examples are exploited in order to illustrate the effectiveness of the proposed design methods.
A BINARY SCENARIO FOR THE FORMATION OF STRONGLY MAGNETIZED WHITE DWARFS
Authors: NORDHAUS JASON
Published: January 2012

Since their initial discovery, the origin of isolated white dwarfs (WDs) with magnetic fields in excess of ~1 MG has remained a mystery. Recently, the formation of these high-field magnetic WDs has been observationally linked to strong binary interactions incurred during post-main-sequence evolution. Planetary, brown dwarf or stellar companions located within a few AU of main-sequence stars may become engulfed during the primary's expansion off the main sequence. Sufficiently low-mass companions in-spiral inside a common envelope until they are tidally shredded near the natal white dwarf. Formation of an accretion disk from the disrupted companion provides a source of turbulence and shear which act to amplify magnetic fields and transport them to the WD surface. We show that these disk-generated fields explain the observed range of magnetic field strengths for isolated, high-field magnetic WDs. Additionally, we discuss a high-mass binary analogue which generates a strongly-magnetized WD core inside a pre-collapse, massive star. Subsequent core-collapse to a neutron star may produce a magnetar.
MAGNETIC FIELD AND TEMPERATURE EFFECTS ON STRANGELETS
Authors: LÓPEZ FUNE ERNESTO , PÉREZ MARTÍNEZ AURORA , MANREZA PARET DARYEL , GONZÁLEZ FELIPE RICARDO
Published: January 2012

The main properties of magnetized strangelets, namely, their energy per baryon, radius and electric charge, are studied in the unpaired strange quark matter phase. Temperature effects are taken into account in order to study their stability compared to the 56Fe isotope and non-magnetized strangelets within the framework of the MIT bag model. It is concluded that the presence of a magnetic field tends to stabilize more the strangelets, even when temperature is considered. We find that the electric charge is modified in the presence of the magnetic field, leading to higher charge values for magnetized strangelets, when compared to the non-magnetized case.
EFFECTS OF GALACTIC GAMMA RAYS BURSTS ON PLANETARY ATMOSPHERES
Authors: MARTÍN OSMEL , CÁRDENAS ROLANDO , HORVATH JORGE E. , PEÑATE LIUBA
Published: January 2012

We discuss the potential past incidence of a galactic gamma ray burst on Earth. Rough estimates for the relative frequencies of this kind of event are given, for the different eons of our planet's geological history. Additionally, we explore the effectiveness of the ozone layer of different paleo-atmospheres to shield the surface of the planet from the ultraviolet flash, which arises as a short-term effect after the incidence of a galactic gamma ray burst.
KAON CONDENSATION AND THE NUCLEAR EQUATION OF STATE
Authors: GOMES ROSANA O. , HADJIMICHEF DIMITER , VASCONCELLOS CÉSAR A. Z. , MESQUITA ALEXANDRE , RAZEIRA MOISÉS , PÉREZ MARTÍNEZ AURORA , PÉREZ ROJAS HUGO , MANREZA PARET DARYEL
Published: January 2012

We study the effects of phase transition in the equation of state of a neutron star containing a condensate of anti-kaons, using an effective model with derivative couplings. In our formalism, nucleons interact through the exchange of σ, ω, ϱ, and δ meson fields in the presence of electrons and muons to accomplish electric charge neutrality and beta equilibrium. The phase transition to the anti-kaons condensate was implemented through the Gibbs conditions combined with the mean-field approximation, giving rise to a mixed phase of coexistence between hadron matter and the condensed of anti-kaons. In conclusion, we have found that isovector meson degrees of freedom contribute to tighten the Equation of State of Neutron Stars.
A FUZZY BAG MODEL FOR BARYON-DIBARYON PHASE TRANSITION IN NEUTRON STARS
Authors: ROCHA ALBERTO S. S. , VASCONCELLOS CÉSAR A. Z. , COELHO HELIO T.
Published: January 2012

We propose a model for dibaryon stars which takes into account the internal structure of nucleons via a fuzzy bag model. This choice of nuclear model avoids nucleon self-energy divergences as in the MIT model, and also considers a softer bag surface, thus eliminating the disadvantage of an abrupt transition between the interior of the bag and the external medium. We obtain results for the equation of state and for the mass-radius relation for the dibaryon star. Our results indicate a smaller maximum mass for dibaryon stars as compared to neutron stars, mainly due to the relaxation of the interior Fermi pressure in the dibaryon-populated star core.
SELF-MAGNETIZATION IN ELECTROWEAK VACUUM AND IN VERY DENSE SYSTEMS
Authors: PÉREZ ROJAS HUGO , RODRÍGUEZ QUERTS ELIZABETH
Published: January 2012

For charged vector bosons (W bosons) of mass mw, magnetization diverges for B → Bcw, which suggests that if the magnetic field is large enough, it can be self-consistently maintained. For photons bearing an anomalous magnetic moment, having a sufficiently large density, their contribution to magnetization might become of the same order than the applied external field, leading also to self-magnetization. We discuss these models in connection to the case of radiation in equilibrium at high temperature (T ~ mc2) coexisting with hot magnetized electron-positron pairs.
ANALYTIC SOLUTIONS OF QCD MOTIVATED HAMILTONIANS AT LOW ENERGY
Authors: YÉPEZ TOCHTLI , AMOR A. , HESS PETER O. , SZCZEPANIAK A. , CIVITARESE O.
Published: January 2012

A model Hamiltonian, motivated by QCD, is investigated in order to study only the quark sector, then only the gluon sector and finally both together. Restricting to the pure quark sector and setting the mass of the quarks to zero, we find analytic solutions, involving two to three orbitals. Allowing the mass of the quarks to be different to zero, we find semi-analytic solutions involving an arbitrary number of orbitals. Afterwards, we indicate on how to incorporate gluons.
MONITORING AND ANALYSIS CONCERNS IN WORKFLOW APPLICATIONS: FROM CONCEPTUAL SPECIFICATIONS TO CONCRETE IMPLEMENTATIONS
Authors: GONZÁLEZ OSCAR , CASALLAS RUBBY , DERIDDER DIRK
Published: January 2012

Workflow monitoring and analysis concerns aim at identifying potential improvements of workflow applications. This paper presents an approach to specify and implement monitoring and analysis concerns on workflow applications raising the level of abstraction for workflow analysts. First, the specification of monitoring and analysis concerns is declared in a technology-independent way with a domain-specific language named MonitA. MonitA makes extensive use of the data available in the workflow application and its constituents to enhance the monitoring and analysis specifications. Second, we defined and implemented a strategy to assist developers to enhance a given workflow technology to support the generation of the monitoring and analysis code and its composition with the workflow application. This instrumentation-based approach enables the monitoring and analysis of workflow applications during their operational execution. We illustrate the flexibility of our approach by targeting different workflow platforms and different workflow applications.
STUDY OF LEG MOVEMENT IN ONE- AND TWO-LEGGED HOPPING
Authors: RAHIKAINEN AHTI , AVELA JANNE , VIRMAVIRTA MIKKO
Published: January 2012

This study was based on the previous research where mechanics of the leg-pushing phase in shot put was studied. The present paper examined the functional mechanics of leg movements during the ground contact of the jumps on one leg and on two legs. The principle of the measuring method was to photograph the movement in series of subject images on one frame where the marker lights attached to the subject can be seen as broken light-lines. The measuring accuracy of the system (time and distance) proved to be very high. This new measuring method is a useful complement to the existing methods. The aim of the study was to approximate the measured points by a suitable curve. Two equations (representing damped oscillatory motion and sine-formed motion) derived for the path of the center of gravity in jump on one leg and on two legs fitted well the experimental results while the equation of strengthening oscillatory motion did not match the measured paths of motion. However, it was hypothesized that vertical displacement-time curve may become a strengthening oscillatory motion as the leg force exertion increases. The model of leg movement of the present paper was compared with the earlier model of the same equation of motion.
CONFORMATION AND CONFINEMENT ENERGY OF INTERACTING END-GRAFTED MOLECULES
Authors: LIN YUAN , YAO SHUHUAI
Published: January 2012

The conformation and confinement energy of flexible molecules grafted on a surface are considered in the framework of classical "random flight" model. Interactions among molecules are included in the analysis and closed form solutions are presented for two limiting cases where the core interaction is either very strong or very weak. The case of stiff molecules is also considered via a different approach where their thermally-induced bending deformations, as well as interactions, have been taken into account. We will demonstrate that, under seemingly identical conditions, the behavior of stiff molecules is quite different from that of flexible ones. Predictions obtained here agree with various experimental observations on the grafting density of single- and double-stranded DNAs on a gold surface.
NEW FOCUSED ULTRASOUND TRANSDUCER FOR FAT CELL DISRUPTION
Authors: CUI YANG , PENG JUE , TANG HU , WANG TIANFU , CHEN SIPING
Published: January 2012

Being an emerging body-shaping technology of fat cell disruption, high-intensity focused ultrasound has been investigated intensively in recent years for its favorable natures such as painlessness, safety and noninvasion. One of the major problems for the technology, however, is the overheating of transducers. In this study, we modified the transducer design in order to solve the overheating problem. We simulated the performance of the modified design by finite element analysis and fabricated the newly designed transducer. By measuring the actual performance data, we proved that the new design can effectively reduce temperature rise while keeping the acoustic intensity field unaffected.
Vaccines for Malaria: How Close Are We?
Authors: Thera Mahamadou A. , Plowe Christopher V.
Published: January 2012

Vaccines are the most powerful public health tools mankind has created, but malaria parasites are bigger, more complicated, and wilier than the viruses and bacteria that have been conquered or controlled with vaccines. Despite decades of research toward a vaccine for malaria, this goal has remained elusive. Nevertheless, recent advances justify optimism that a licensed malaria vaccine is within reach. A subunit recombinant protein vaccine that affords in the neighborhood of 50% protective efficacy against clinical malaria is in the late stages of clinical evaluation in Africa. Incremental improvements on this successful vaccine are possible and worth pursuing, but the best hope for a highly efficacious malaria vaccine that would improve prospects for malaria eradication may lie with the use of attenuated whole parasites and powerful immune-boosting adjuvants.
Demography of High-Redshift AGN
Authors: Fiore Fabrizio , Puccetti Simonetta , Mathur Smita
Published: January 2012

High-redshift AGN holds the key to understanding early structure formation and to probe the Universe during its infancy. We review the latest searches for high-zAGN in the deepest X-ray field so far, the Chandra Deep Field South (CDFS) 4 Msecond exposure. We do not confirm the positive detection of a signal in the stacked Chandra images at the position ofz~6galaxies recently reported by Treister and collaborators (2011). We presentz>3X-ray sources number counts in the 0.5–2 keV band, obtained joining CDFS faint detections (see Fiore et al. (2011)), with Chandra-COSMOS and XMM-COSMOS detections. We use these number counts to make predictions for surveys with three mission concepts: Athena, WFXT, and a Super-Chandra.
Differential Downregulation of E-Cadherin and Desmoglein by Epidermal Growth Factor
Authors: Chavez Miquella G. , Buhr Christian A. , Petrie Whitney K. , Wandinger-Ness Angela , Kusewitt Donna F. , Hudson Laurie G.
Published: January 2012

Modulation of cell : cell junctions is a key event in cutaneous wound repair. In this study we report that activation of the epidermal growth factor (EGF) receptor disrupts cel : cell adhesion, but with different kinetics and fates for the desmosomal cadherin desmoglein and for E-cadherin. Downregulation of desmoglein preceded that of E-cadherinin vivoand in an EGF-stimulatedin vitrowound reepithelialization model. Dual immunofluorescence staining revealed that neither E-cadherin nor desmoglein-2 internalized with the EGF receptor, or with one another. In response to EGF, desmoglein-2 entered a recycling compartment based on predominant colocalization with the recycling marker Rab11. In contrast, E-cadherin downregulation was accompanied by cleavage of the extracellular domain. A broad-spectrum matrix metalloproteinase inhibitor protected E-cadherin but not the desmosomal cadherin, desmoglein-2, from EGF-stimulated disruption. These findings demonstrate that although activation of the EGF receptor regulates adherens junction and desmosomal components, this stimulus downregulates associated cadherins through different mechanisms.
Damping Analyses of Structural Vibrations and Shunted Piezoelectric Transducers
Authors: Mohammadi Saber , Khodayari Akram
Published: January 2012

Piezoelectric transducers in conjunction with appropriate electric networks can be used as a mechanical energy dissipation device. Alternatively, undesired mechanical energy of a structure could be converted into electrical energy that can be dissipated through a shunt network in the form of Joule heating. This paper presents an experimental method to calculate damping energy in mechanical systems. However, the mathematical description of damping mechanism is much more complicated, and any process responsible for the occurrence of damping is very intricate. Structural and piezoelectric damping are calculated and analysed in the case of pulse switching or SSDI semiactive vibration control technique. This technique which was developed in the field of piezoelectric damping consists in triggering the inverting switch on each extremum of the piezoelectric voltage which induces an increase of the electromechanical energy conversion.
Numerical Solution of the Modified Equal Width Wave Equation
Authors: Karakoç Seydi Battal Gazi , Geyikli Turabi
Published: January 2012

Numerical solution of the modified equal width wave equation is obtained by using lumped Galerkin method based on cubic B-spline finite element method. Solitary wave motion and interaction of two solitary waves are studied using the proposed method. Accuracy of the proposed method is discussed by computing the numerical conserved laws and error norms. The numerical results are found in good agreement with exact solution. A linear stability analysis of the scheme is also investigated.
The Methodology of Doppler-Derived Central Blood Flow Measurements in Newborn Infants
Authors: de Waal Koert A.
Published: January 2012

Central blood flow (CBF) measurements are measurements in and around the heart. It incorporates cardiac output, but also measurements of cardiac input and assessment of intra- and extracardiac shunts. CBF can be measured in the central circulation as right or left ventricular output (RVO or LVO) and/or as cardiac input measured at the superior vena cava (SVC flow). Assessment of shunts incorporates evaluation of the ductus arteriosus and the foramen ovale. This paper describes the methodology of CBF measurements in newborn infants. It provides a brief overview of the evolution of Doppler ultrasound blood flow measurements, basic principles of Doppler ultrasound, and an overview of all used methodology in the literature. A general guide for interpretation and normal values with suggested cutoffs of CBFs are provided for clinical use.
Influence of Surgical Technique on Mastectomy and Reexcision Rates in Breast-Conserving Therapy for Cancer
Authors: Unzeitig Alison , Kobbermann Anne , Xie Xian-Jin , Yan Jingsheng , Euhus David , Peng Yan , Sarode Venetia , Moldrem Amy , Leitch A. Marilyn , Andrews Valerie , Rao Roshni
Published: January 2012

Introduction. Breast conserving surgery (BCS) requires tumor excision with negative margins. Reexcision rates of 30–50% are reported. Ultrasound localization, intraoperative margin pathology, and specimen mammography have reduced reexcisions, but require new equipment. Cavity shave margin (CSM) is a technique, utilizing existing equipment, that potentially reduces reexcision. This study evaluates CSM reexcision impact.Methods. 522 cancers treated with BCS were reviewed. Patients underwent standard partial mastectomy (SPM) or CSM. Data collected included demographics, pathology, and treatments.Results. 455 SPMs were compared to 67 CSMs. Analysis revealed no differences in pathology, intraductal component, or neoadjuvant chemotherapy. Overall reexcision rate = 43%. Most reexcisions were performed for DCIS at margin. SPMs underwent 213 reexcisions (46.8%), versus 16/67 (23.9%) CSMs (P= 0.0003). Total mastectomy as definitive procedure was performed after more SPMs (P= 0.009). Multivariate analysis revealed CSM, % DCIS, tumor size, and race to influence reexcisions.Conclusions. CSM is a technique that reduces reexcisions and mastectomy rates.
Dosage Optimization for Letrozole Treatment in Clomiphene-Resistant Patients with Polycystic Ovary Syndrome: A Prospective Interventional Study
Authors: Rahmani Elham , Ahmadi Shahnaz , Motamed Niloofar , Maneshi Hesam_Oddin
Published: January 2012

Objective. Dose adjustment for induction of ovulation is one of the most important problem.Methods. In a prospective interventional study, 44 clomiphene-resistant infertile patients (113 cycles) were selected from the Abolfazl Infertility Clinic of Bushehr University of Medical Sciences. Letrozole was given orally in a dose of 2.5 mg, 5 mg, and 7.5 mg, respectively. If the patient displayed no response, the dosage was increased.Results. In this patients ovulation occurred in 50 cycles (44.24%), clinical pregnancy rate according to number of cycles was 23.89% (27 of 113 cycles) and according to the number of patients was 61.36% (27 of 44 patients). In the 2.5, 5, and 7.5 groups, follicles occurred in 22.9%, 42.1%, and 85.18% of cycles, and pregnancy rate was 14.58%, 28.94% and, 33.33%, respectively.Conclusions. It is better to administer Letrozole at a lower dosage to prevent complications and increase the dose based on sonographic results antral follicular count, anti-Müllerian hormone, LH/FSH, and estradiol.
Fetal Vibroacoustic Stimulation in Computerized Cardiotocographic Analysis: The Role of Short-Term Variability and Approximate Entropy
Authors: Annunziata Maria Laura , Scala Mariamaddalena , Giuliano Natascia , Tagliaferri Salvatore , Imperato Olga Carmela Maria , Esposito Francesca Giovanna , Campanile Marta , Di Lieto Andrea
Published: January 2012

The aim of this study was to evaluate the impact of vibroacoustic stimulation (VAS) on computerized cardiotocography short-term variability (STV) and approximate entropy (ApEn) in both low- and high-risk pregnancies. VAS was performed on 121 high- and 95 low-risk pregnancies after 10 minutes of continuous quiet, while their FHR parameters were monitored and recorded by cCTG analysis. Fetal heart rate was recorded using a computer-assisted equipment. Baseline FHR, accelerations, decelerations, STV, long-term irregularity (LTI), ApEn, and fetal movements (FMs) were calculated for defined observational periods before VAS and after 10 minutes. Data were also investigated in relationship with the perinatal outcome. In each group of patients, FHR after VAS remained almost unmodified. Fetal movements significantly increased after VAS in both groups. Results show that only in the high-risk pregnancies, the increase of STV and the decrease of ApEn after VAS were significantly associated with favorable perinatal outcomes.
The Isolation of a NewS-Methyl Benzothioate Compound from a Marine-DerivedStreptomycessp.
Authors: Mahyudin Nor Ainy , Blunt John W. , Cole Anthony L. J. , Munro Murray H. G.
Published: January 2012

The application of an HPLC bioactivity profiling/microtiter plate technique in conjunction with microprobe NMR instrumentation and access to the AntiMarin database has led to the isolation of a new1. In this example,1was isolated from a cytotoxic fraction of an extract obtained from marine-derivedStreptomycessp. cultured on Starch Casein Agar (SCA) medium. The 1D and 2D1H NMR and ESIMS data obtained from 20 μg of compound1fully defined the structure. The known2was also isolated and readily dereplicated using this approach.
Forms, Crosstalks, and the Role of Phospholipid Biosynthesis in Autophagy
Authors: Pereira Leanne , Girardi John Paul , Bakovic Marica
Published: January 2012

Autophagy is a highly conserved cellular process occurring during periods of stress to ensure a cell's survival by recycling cytosolic constituents and making products that can be used in energy generation and other essential processes. Three major forms of autophagy exist according to the specific mechanism through which cytoplasmic material is transported to a lysosome. Chaperone-mediated autophagy is a highly selective form of autophagy that delivers specific proteins for lysosomal degradation. Microautophagy is a less selective form of autophagy that occurs through lysosomal membrane invaginations, forming tubes and directly engulfing cytoplasm. Finally, macroautophagy involves formation of new membrane bilayers (autophagosomes) that engulf cytosolic material and deliver it to lysosomes. This review provides new insights on the crosstalks between different forms of autophagy and the significance of bilayer-forming phospholipid synthesis in autophagosomal membrane formation.
Economic development in the US alters course because of recession
Authors: Renault Catherine S
Published: January 2012

States in the USA have been reacting to increased budgetary pressures by reducing discretionary budgets, including those for economic development. As a result, state economic development organizations are adopting new strategies such as innovation, clusters, entrepreneurship and economic gardening. They are increasingly partnering with regional organizations and the private sector, including in some instances reorganizing as a public-private partnership in lieu of a stateagency. Calls for increased efficiency and effectiveness of economic development investments have not to date been met by increased evaluation or accountability.
How does the World Trade Organization know? The mobilization and staging of scientific expertise in the GMO trade dispute
Authors: Bonneuil Christophe , Levidow Les
Published: January 2012

The World Trade Organization (WTO) dispute settlement procedure is a key arena for establishing global legal norms for what counts as relevant knowledge. As a high-profile case, the WTO trade dispute on GMOs mobilized scientific expertise in somewhat novel ways. Early on, the Panel put the dispute under the Sanitary and Phytosanitary (SPS) Agreement through a new legal ontology; it classified transgenes as potential pests and limited all environmental issues to the ‘plant and animal health’ category. The selection of scientific experts sought a multi-party consensus through a fast adversarial process, reflecting a specific legal epistemology. For the SPS framing, focusing on the defendant’s regulatory procedures, the Panel staged scientific expertise in specific ways that set up how experts were questioned, the answers they would give, their specific role in the legal arena, and the way their statements would complement the Panel’s findings. In these ways, the dispute settlement procedure co-produced legal and scientific expertise within the Panel’s SPS framework. Moreover, the Panel operated a procedural turn in WTO jurisprudence by representing its findings as a purely legal-administrative judgement on whether the EC’s regulatory procedures violated the SPS Agreement, while keeping implicit its own judgements on substantive risk issues. As this case illustrates, the WTO settlement procedure mobilizes scientific expertise for sophisticated, multiple aims: it recruits a source of credibility from the scientific arena, thus reinforcing the standard narrative of ‘science-based trade discipline’, while also constructing new scientific expertise for the main task – namely, challenging trade restrictions for being unduly cautious.
Divided by a common concept? Assessing the implications of different conceptualizations of hate crime in the European Union
Authors: Garland Jon , Chakraborti Neil
Published: January 2012

In recent years the European Union (EU) has witnessed rising levels of hate crime. However, although there have been a number of legislative and other policy initiatives introduced across the EU to combat such offences, these have developed in a piecemeal and sometimes half-hearted fashion. This article outlines the difficulties evident in theorizing hate crime and how these problems have been reflected in the divergent ways that hate crime legislation has developed across the EU. It argues that an approach to combating hate crime based on human rights, which is endorsed by many EU institutions, has failed to tackle the problem effectively and has resulted in the uneven protection of hate crime victim groups. By utilizing an individual rather than a group-based human rights approach, the damaging nature and effect of such ‘targeted victimization’ upon all hate crime victims can be better understood and addressed.
Pillared metal(IV) phosphate-phosphonate extraction of actinides
Authors: Burns J. D. , Clearfield A. , Borkowski Marian , Reed Donald T.
Published: January 2012

Four pillared metal(IV) phosphate-phosphonate ion exchange materials were synthesized and characterized. Studies were conducted to determine their affinity for the lanthanides (Ln´s) and actinides (An´s). It was determined that by simply manipulating the metal source (Zr or Sn) and the phosphate source (H3PO4 or Na3PO4) large differences were seen in the extraction of the Ln and An species. K
d values higher than 4×105 were observed for the AnO2
2+ species in nitric acid at pH 2. These basic uptake experiments are important, as the data they provide may indicate the possibility of a separation of Ln´s from An´s or even more notably americium from curium and Ln´s.
Optical Trapping, Biosensing, and Spectroscopy in a Single Plasmonic Platform
Authors: Cetin Arif E. , Yilmaz Cihan , Yanik Ahmet , Somu Sivasubramanian , Busnaina Ahmed , Altug Hatice
Published: January 2012

We propose plasmonic platform that can enable optical trapping, spectroscopy and biosensing, all in the same platform. The system is based on periodic arrays of gold nanopillars fabricated on a supporting gold layer. The proposed platform is highly desirable for biosensing applications since it supports highly refractive index sensitivities as large as 675 nm/RIU which. The spectrally sharp resonances provides large figure of merits as large as 112.5. As the nanopillar array supports large near-field intensities accessible to the biomolecules in the sample around the platform, as large as 10.000 times, the proposed structure can be used for surface enhanced spectroscopy applications. The pillar array also supports plasmonic hot spots with high near-field intensity gradient leading to large gradient forces, 350 pN/W/μm2 which is needed for optical trapping applications.
One-Step Synthesis of Stable Gold Nanoparticles on Eco-friendly Ionic Liquid
Authors: Anantha P , Wang Xiu , Wong C.C.
Published: January 2012

Metallic nanoparticles are often obtained by chemical decomposition or reactive techniques involving the extensive usage of harmful reducing or stabilizing agents. A facile green synthesis technique resulting in readily exploitable nanoparticle dispersion in ionic liquid without the use of any additional agents is reported here. 1-Propyl- 3- Methyl Imidazolium Iodide (PMIM(I)) is a non-volatile, thermally stable and non-toxic ionic liquid. This eco-friendly liquid is used as the substrate for thermal evaporation of gold to obtain stable gold nanoparticles. On being examined by Transmission Electron Microscopy the high monodispersity in their sizes was revealed. The byproduct free, ‘clean’ processing technique helps in obtaining un-contaminated particles. The thermal evaporation method used (for the generation of metallic vapor) plays a significant role in the difference in kinetics of the formation and growth of nanoparticles, unlike the widely reported sputtering technique for vapor generation. The formed particles are deposited only on the top surface of the liquid. Thus the nucleation and growth of the particles can be considered to have occurred by surface diffusion process only. A deeper investigation into the formation kinetics has the potential application for synthesizing other nanomaterials via this environmental friendly approach.
Anodic and cathodic pre-treatment effects on BDD surface to deposit copper nanoparticles applied to nitrate reduction
Authors: Santos L. C. D. , Couto A. B. , Matsushima J. T. , Forti M.C. , Baldan M. R. , Ferreira N. G.
Published: January 2012

The influence of anodic and cathodic pre-treatment on boron doped diamond (BDD) surface for copper (Cu) electrodeposition was studied to assess Cu particle consolidation on BDD electrode. These modified electrodes were applied to study the nitrate electrochemical reduction process. The obtained results showed that the BDD surface cathodically treated presented high Cu particle density as well as even distribution on the electrode surface after the electrodeposition process. For samples anodically treated the electrodeposited Cu was dispersed with lower particle density. This behavior was attributed to a high electrode conductivity imposed by the cathodic pre-treatment leading to an increase in the BDD surface hydrogenation. Therefore, one can conclude that for electrochemical nitrate reduction the anodically treated BDD has a better reproducibility. This response is attributed to the Cu particle consolidation on BDD electrode due to the oxygen surface terminations induced by the anodic pretreatment.
Copper Oxide Edge-Termination for GaN Schottky Barrier Diodes with Low Turn-on Voltage
Authors: Minoura Yuichi , Okamoto Naoya , Kanamura Masahito , Imada Tadahiro , Ohki Toshihiro , Imanishi Kenji , Watanabe Keiji , Joshin Kazukiyo , Kikkawa Toshihide
Published: January 2012

In this study, we propose copper oxide (CuOx) edge-termination for GaN-based Schottky barrier diodes (SBDs) with low turn-on voltage. CuOx fabricated by thermal oxidization of sputtered Cu film at 275°C consisted mainly of Cu2O which is known as a p-type semiconductor. We applied CuOx edge-termination to GaN SBDs with tantalum (Ta) Schottky electrode which has low work function of 4.25 eV. The experimental results of current-voltage characteristics insisted that CuOx edge-termination structure was effective to increase breakdown voltage of GaN SBDs with keeping low turn-on voltage of 0.29 V at 10 A/cm2.
Couplings in GaAs/AlGaAs/Metal Photonic Waveguides with Metallic Variations
Authors: Shih Meng-Mu
Published: January 2012

To have better light-emitting performance, semiconductor-metal periodic photonic waveguides can generate stable wavelengths. This work constructs a multi-parameter model to compute the backward-wave mode-coupling coefficients, which are important to the analysis and performance of photonic devices. For such a semiconductor-metal hybrid structure, a proper photonic technique needs to be utilized to solve this computational complexity.

Numerical results demonstrate how the materials of metal gratings, the corrugation amplitudes of metal gratings, and the metallic aluminum mole fraction can affect the coupling coefficients. Further physical interpretation and discussion can support and explain the above results. The results can help engineers decide the values of parameters used in fabrication. Future work and applications will be proposed.
Infrared ellipsometry and near-infrared-to-vacuum-ultraviolet ellipsometry study of free-charge carrier properties in In-polar p-type InN
Authors: Schöche Stefan , Hofmann Tino , Ben Sedrine Nebiha , Darakchieva Vanya , Wang Xinqiang , Yoshikawa Akihiko , Schubert Mathias
Published: January 2012

We apply infrared spectroscopic ellipsometry (IRSE) in combination with near-infrared to vacuum-ultraviolet ellipsometry to study the concentration and mobility of holes in a set of Mg-doped In-polar InN samples of different Mg-concentrations. P-type behavior is found in the IRSE spectra for Mg-concentrations between 1x1018 cm-3 and 3x1019 cm-3. The free-charge carrier parameters are determined using a parameterized model that accounts for phonon-plasmon coupling. From the NIR-VUV data information about layer thicknesses, surface roughness, and structural InN layer properties are extracted and related to the IRSE results.