bluuebunny/crossref_metadata_2025 huggingface dataset:
ANISOTROPIC HARDNESS ESTIMATIONS OF SOME INORGANIC FUNCTIONAL MATERIALS
Authors: YANG PENG , LI KEYAN , XUE DONGFENG
Published: February 2012

For the first time, this work indicates that mechanical concerns of inorganic materials are highly demanded when well optimizing their functional applications. We quantitatively give the proper data of hardness on different planes of some representative inorganic functional materials including borides, carbides, nitrides and oxides. This work clearly indicates mechanical importance in studying functionality of inorganic materials, and provides people guidance in the practical applications of these materials.
SYNTHESIS AND ELECTROCHEMICAL PROPERTIES OF NANO FIBER HOLLANDITE-TYPE MANGANESE OXIDES USING A HYDROTHERMAL METHOD
Authors: KADOMA YOSHIHIRO , AKAHIRA TATSUYA , FUKUDA TSUBASA , UI KOICHI , KUMAGAI NAOAKI
Published: February 2012

Hollandite-type MnO2 and its Co -substituted samples have been synthesized by hydrothermal method from MnSO4 , CoSO4 and K2S2O8 solutions. The hydrothermal products from MnSO4 and K2S2O8 solutions consisted of the hollandite-type [2 × 2] tunnel structure at 100°C–150°C for 12 h, which was transformed to pyrolusite-type [1 × 1] tunnel structure by hydrothermal treatment at 150°C for longer times of 24–48 h or at a higher temperature of 180°C. On the other hand, the hydrothermal products from MnSO4 , CoSO4 and K2S2O8 solutions at 150°C–180°C for 12–48 h consisted of the hollandite-type MnO2 phase. The Co -substituted samples showed higher initial discharge capacity (180–200 mAh (g-oxide)-1) than that of non-substituted hollandite-type MnO2 (130–160 mAh (g-oxide)-1) at 50 mA g-1.
HYPERSTABILIZATION OF MARTENSITES
Authors: KUSTOV SERGEY , SANTAMARTA RUBEN , SALAS DANIEL , CESARI EDUARD , SAPOZHNIKOV KONSTANTIN , VAN HUMBEECK JAN
Published: February 2012

The effect of hyperstabilization of martensite implies that the reverse martensitic transformation proceeds in two well separated stages. Namely, a small fraction of martensite (of the order of 10%) retransforms upon heating into the parent phase over a temperature range slightly higher than the nominal reverse transformation temperature, whereas the rest of the martensite retransforms through a re-nucleation of fine lamellae of the parent phase. The renucleation stage of the transformation is well defined and requires strong overheating of the order of 300 K with respect to the nominal transformation. In this letter, the results are discussed of a study of the hyperstabilization effect in different martensitic structures: faulted [Formula: see text] martensite in Cu–Al–Be system and twinned martensite in ferromagnetic Ni–Fe–Ga crystals by means of differential scanning calorimetry, transmission electron microscopy and internal friction. The conclusion has been drawn that hyperstabilization implies a severe blocking of the motion of interphase boundaries during the reverse transformation, which can be produced either due to a high concentration of highly mobile quenched-in defects ("sweeping" of defects during the reverse transformation) or due to a creation of obstacles by preliminary plastic deformation. The former mechanism requires very intense diffusion of quenched-in defects assisted by dislocations/interfaces, which has been confirmed by internal friction studies. It has been shown that the renucleation stage, which occurs at around 600 K for different alloys, is preceded by a relaxation internal friction peak. A possible role of this relaxation in renucleation of the parent phase is discussed.
THIN NiTi WIRES WITH REDUCED THERMAL HYSTERESIS FOR SHAPE MEMORY ACTUATORS
Authors: CASATI RICCARDO , TUISSI AUSONIO , BELOCHAPKINE SERGUEI , DICKINSON CALUM , TOFAIL SYED A. M.
Published: February 2012

NiTi wires are successfully employed asthermal actuators: devices able to convert thermal energy into mechanical energy, generating force and displacement. So far, researchers have highlighted the influence of various parameters on shape memory characteristics of the material, such as chemical composition, cold working, heat treatment and cycling. This study is aimed to prove that drawing histories, in particular the number of drawing steps performed to achieve a certain cold working level, are fundamentally important on functional properties of wires. This process parameter involves significant changes in terms of thermal hysteresis width. These alterations are still observable on wires thermo-mechanical cycled, therefore on products ready to be employed for actuators.
THE INCREASE OF THE MARTENSITIC DEFORMATION DURING SHAPE MEMORY EFFECT IN DEFORMED TiNi
Authors: FIRSTOV GEORGIY , KOVAL YURI , LOTKOV ALEKSANDR , GRISHKOV VICTOR , VAN HUMBEECK JAN
Published: February 2012

The evolution of the ultrafine structure, obtained at thermal treatment below recrystallization, and its effect onto shape memory characteristics in NiTi alloy was under study. It was shown that low temperature annealing (< 0.5 Tmelt) of the hot rolled NiTi leads to the structure refinement accompanied by the growth in accumulated martensite deformation. It was suggested that this is possible due to the increase of the volume fraction of martensite crystals properly oriented in respect to external stress.
FATIGUE BEHAVIOR CHARACTERIZATION OF NITINOL FOR PERIPHERAL STENTS
Authors: PETRINI LORENZA , WU WEI , DORDONI ELENA , MEOLI ALESSIO , MIGLIAVACCA FRANCESCO , PENNATI GIANCARLO
Published: February 2012

Nitinol stents are nowadays widely used for the treatment of occlusions in peripheral arteries. However, the expansion of this indication has also highlighted some complications. In particular, the patient daily activities expose the peripheral arteries to large and cyclic deformations which may cause long-term failure of the device and consequently re-occlusion of the artery. Accordingly, the assessment of the stent fatigue rupture is of primary importance to assure the effectiveness of stenting procedure. However the fatigue behavior characterization of Nitinol for peripheral stent is a quite difficult problem because of the complexity of the in vivo solicitations the stent is subjected to and the strong nonlinearity in the material response. In this paper we approached the problem in two steps: (i) in the first step the study of the stent solicitations under realistic (physiological) conditions was performed through the use of numerical simulations which allowed sophisticated patient-specific models of the stenting procedure; (ii) in the second step, the previous results were used for the design of an experimental campaign and the following execution of the tests for the material mechanical characterization and fatigue life study. The tests were performed on Nitinol specimens derived from the same tubes used for producing a commercial peripheral stent and created following the same procedure employed for the device. As a consequence of the small dimension of the specimens, a preliminary design of the experimental test set-up was also required. The obtained results allowed a sufficiently accurate characterization of the stent material fatigue behavior in the range of interest.
FLEXURAL VIBRATION SUPPRESSION OF GLASS FIBER/CuZnAl SMA COMPOSITE
Authors: BIFFI CARLO ALBERTO , BASSANI PAOLA , TUISSI AUSONIO , CARNEVALE MARCO , LECIS NORA , CONTE ANTONIETTA LO , PREVITALI BARBARA
Published: February 2012

This work proposes the functional characterization of a composite material, suitable for passive suppression of flexural vibration of beams and shells. Two patterned thin sheets of CuZnAl Shape Memory Alloy (SMA) are embedded into a layered beam of glass fiber. The composite combines the density and stiffness of the glass fiber with high damping properties of SMA in martensitic state. Properly shaped patterning of the SMA sheets, for improving adhesion between the SMA and glass fiber, is performed by means of laser technology. The effect of the laser micromachining on transformation temperatures and internal friction properties of the SMA elements are analyzed. Finally, measurements of the structural damping of the layered glass fiber/SMA composite are reported and the flexural vibration suppression, due to the embedded CuZnAl sheets, is shown.
AN AFM INVESTIGATION OF SURFACE ENERGY OF PENTACENE FILMS ON PARYLENE-C AND BENZOCYCLOBUTENE
Authors: IAZYKOV M. , EROUEL M. , VILLEY R. , SOUTEYRAND E. , TARDY J. , PHANER-GOUTORBE M. , SKRYSHEVSKY V. A.
Published: February 2012

In view to put in light morphology peculiarities of pentacene, the widely used material for organic transistors, a detailed atomic force microscopy (AFM) investigation of the pentacene growth mode in relationship with the film thickness (in the range 6–60 nm) is reported. Local surface energy measurements based on contact AFM spectroscopy were performed to explain the thickness dependent morphology of the pentacene films onto two polymer dielectrics (parylene-C and benzocyclobutene). Our analysis provided an exhaustive description not only of the accessible film surface but also of its inner structural properties. Evidenced by these approaches, a critical thickness of 30 nm was found in relation with a transition from the orthorhombic thin film phase to triclinic bulk phase for pentacene growth on parylene-C and benzocyclobutene. This thickness was previously observed to be corresponding to organic field effect transistors (OFETs) with optimized mobility.
DUAL-FUNCTION LAYER OF MESOPOROUS STRUCTURE ANATASE TiO2 FOR HIGH PERFORMANCE DYE-SENSITIZED SOLAR CELLS
Authors: WANG YONG , TAN YU , LIU BIQIONG , LIU BITAO
Published: February 2012

Pure anatase TiO2 spheres with mesoporous structure were prepared by a simple urea assisted hydrothermal process at low temperature. X-ray Diffractometer, Scanning Electron Microscope, Transmission Electron Microscope, and N2 adsorption-desorption were used to characterize TiO2 . The dye-sensitized solar cells results show that an overall light conversion efficiency of 6.96% which is 36.7% higher than that of the overall efficiency (5.09%) obtained from the P25 photoanode owing to the superior light scattering effect and the high level of dye loading capacity of microspheres.
GIANT DIELECTRIC TUNABLE BEHAVIOR OF Pr-DOPED SrTiO3 AT LOW TEMPERATURE
Authors: WEI T. , SONG Q. G. , ZHOU Q. J. , LI Z. P. , CHEN Y. F. , QI X. L. , GUO S. Q. , LIU J.-M.
Published: February 2012

Contrast with conventional dielectric tunable materials such as barium strontium titanate (BST), here, we report one new dielectric tunable behavior for Sr 1-x Pr x TiO 3 system at low temperature. Giant dielectric tunability is confirmed in this system. More importantly, the efficient dielectric tunability can be realized just using small bias field. In addition, critical threshold electric field is also confirmed. This phenomenon may be related with the competition interaction of polar state with quantum fluctuations.
LARGE-SCALE SYNTHESIS OF TIN-DOPED INDIUM OXIDE NANOFIBERS USING WATER AS SOLVENT
Authors: ALTECOR ALEKSEY , MAO YUANBING , LOZANO KAREN
Published: February 2012

Here we report the successful fabrication of tin-doped indium oxide (ITO) nanofibers using a scalable Forcespinning™ method. In this environmentally-friendly process, water was used as the only solvent for both Polyvinylpyrrolidone (PVP, the sacrificial polymer) and the metal chloride precursor salts. The obtained precursor nanofiber mats were calcinated at temperatures ranging from 500–800°C to produce ITO nanofibers with diameters as small as 400 nm. The developed ITO nanofibers were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction analysis.
REVIEW ON PIEZOELECTRIC, ULTRASONIC, AND MAGNETOELECTRIC ACTUATORS
Authors: DONG SHUXIANG
Published: February 2012

Piezoelectric actuators operating in piezoelectric-induced strain/stress or electromechanical resonance-induced vibration or wave-motion friction drive mechanism have shown many advantages over traditional electromagnetic motors, especially, when miniaturizing into millimeter-scale size, while magnetoelectric actuators operating in magnetostrictive mechanism are capable of piezoelectric self-sensing and remote operation under an applied magnetic field. This paper summarizes the recent progresses in piezoelectric ceramic and single crystal materials based actuators and micromotors, ferromagnetic/ferroelectric laminated magnetoelectric actuators, including rotary, linear, planner, and spherical motion actuators, and bending motion magnetoelectric actuators. Their driving mechanisms, operation properties, and applications are also explained.
TEMPERATURE-INDEPENDENT DIELECTRIC PROPERTIES OF 0.82[0.94Bi0.5Na0.5TiO3–0.06BaTiO3]–0.18K0.5Na0.5NbO3 CERAMICS
Authors: LIU YANG , XU ZHUO , FENG YUJUN
Published: February 2012

In order to explore the high temperature stability of ceramic capacitor, we present temperature-independent dielectric properties of 0.82[0.94Bi0.5Na0.5TiO3–0.06BaTiO3]–0.18K0.5Na0.5NbO3 (BNT–BT–18KNN) ceramics. For different sintered temperature and annealing treatment, the pseudoternary system showed a εr of 2265 at 1 kHz at 35°C with a normalized permittivity ε/ε35°C varying less than ±15% from 11°C to 382°C. This pure perovskite phase with slimmer and heat proof P–E loops possessed energy density of 0.616 J/cm3 with a tolerance of about ±3% in a temperature interval ranging from 20°C to 120°C, which is higher and more temperature stable than most ceramic capacitors, such as PLZST and 0.89BNT–0.06BT–0.05KNN. This relaxor ferroelectric (at room temperature) with parabolic bipolar strain–electric (S(E)) curve showed a quite low temperature dependence of positive strain with less than ±6.5% tolerance from the average value of 0.091% between 20°C and 120°C, which is also more temperature stable than the same composition Zhang et al. reported. These merits demonstrate that the newly produced BNT–BT–18KNN ceramics should be a promising candidate for the development of high-temperature capacitor and actuator materials.
SOLITON SPIN IN AN ADD–DROP OPTICAL FILTER FOR LONG DISTANCE SPIN TRANSPORT
Authors: TEEKA C. , AZIZ M. S. , PIPATSART S. , SRINUANJAN K. , ALI J. , YUPAPIN P. P.
Published: February 2012

A new concept of an optical spin generation using bright and dark soliton conversion behaviors within a modified optical add–drop filters known as a PANDA ring resonator is proposed. The orthogonal solitons can be formed randomly within the system and detected simultaneously at the output ports. Under the resonant condition, the orthogonal solitons corresponding to the left-hand and right-hand solitons (photons) can be generated. Whenever a photon is absorbed by an object, an angular momentum of either +ℏ or -ℏ is imparted to the object, in which two possible spin states known as soliton spins are exhibited. Many soliton spins, i.e., many particles, dynamic spin and long distance spin transport using the proposed design are also discussed.
THE EFFECT OF POLARIZED CURRENTS ON THE CRITICAL CURVE OF SINGLE-DOMAIN PARTICLES WITH QUARTIC CRYSTALLINE ANISOTROPY
Authors: ONICIUC EUGEN , STOLERIU LAURENTIU , STANCU ALEXANDRU
Published: February 2012

The use of polarized currents as tools for influencing the magnetic switching of magnetic materials was an important step in the evolution of modern recording technologies. A new paradigm was opened and new technologies based on this new idea have been developed. However, the modeling effort did not followed at the same pace the technological developments. In this paper, we are analyzing the effect on switching critical curves of the polarized current, which seems to be the most sensitive tool for the moment in evidencing these effects. The most important point of this paper is that we took into consideration the effect of higher order terms in the series expansion of the uniaxial anisotropy free energy and we analyze how these terms are influencing the critical curve shape. The results are discussed in terms of the efficiency of the polarized currents on the switching behavior of macrospins.
INFLUENCE OF SHAPE IMPERFECTION ON DYNAMICS OF VORTEX SPIN-TORQUE NANO-OSCILLATOR
Authors: SKIRDKOV P. N. , BELANOVSKY A. D. , ZVEZDIN K. A. , ZVEZDIN A. K. , LOCATELLI N. , GROLLIER J. , CROS V.
Published: February 2012

The dynamics of vortex gyration under spin-polarized current in a spin-torque nano-oscillator with axial symmetry violated by shape imperfection has been studied by micromagnetic modeling. We have considered the following kinds of shape: the displacement of the nanodisks centers, the pyramidal shape and the shape with several small cutouts. The corresponding frequency spectra of the vortex oscillations are presented. We found that shape imperfection can influence not only fundamental frequency but also can genarate second and higher harmonics. The impact of different types of shape on the vortex dynamics has been analyzed qualitatively. New ideas of microwave signal arising by artificial nonidealities of structure were proposed.
Aspects of German military geology and groundwater development in World War II
Authors: Willig D. , Häusler H.
Published: February 2012

A uniformed geological organization was re-created within the German Army by the start of World War II and developed to comprise 40 centres or teams by 1943. Many specialist geotechnical maps and reports prepared by these military geologists have survived the war as part of the Heringen Collection; some remains in the USA, but other parts are in Germany, notably within the archives of the Bundeswehr Geoinformation Office. German armed forces made use of about 400 geologists in total during the conflict, mostly in the Army. Many of their tasks involved groundwater studies, some including the preparation of groundwater prospect maps. Temporary water supplies were set up during mobile campaigns by planning efficient use or enhancement of existing civilian resources, supplemented by driving shallow ‘Abyssinian’ tube wells, for example, in Operation Sea Lion, the invasion of SE England planned for September 1940 but ultimately cancelled. Sustainable long-term supplies in militarily occupied territory were achieved by rigorous data collection and programmes of well drilling, spring capture or percolation gallery construction, one example being on the Channel Islands between 1940 and 1945. Geophysics sometimes aided the geological and borehole studies that guided deployment of well-drilling teams, for example, in 1941/1942, to support German and Italian forces operational in North Africa.
Building an efficient transcoding overlay for P2P streaming to heterogeneous devices
Authors: Liu Dongyu , Li Fei , Shen Bo , Chen Songqing
Published: February 2012

With the increasing deployment of Internet P2P/overlay streaming systems, more and more clients use mobile devices, such as smart phones and PDAs, to access these Internet streaming services. Compared to wired desktops, mobile devices normally have a smaller screen size, a less color depth, and lower bandwidth and thus cannot correctly and effectively render and display the data streamed to desktops.

To address this problem, in this paper, we propose PAT (Peer-Assisted Transcoding) to enable effective online transcoding in P2P/overlay streaming. PAT has the following unique features. First, it leverages active peer cooperation without demanding infrastructure support such as transcoding servers. Second, as online transcoding is computationally intensive while the various devices used by participating clients may have limited computing power and related resources (e.g., battery, bandwidth), an additional overlay, called metadata overlay, is constructed to instantly share the intermediate transcoding result of a transcoding procedure with other transcoding nodes to minimize the total computing overhead in the system. The experimental results collected within a realistically simulated testbed show that by consuming 6% extra bandwidth, PAT could save up to 58% CPU cycles for online transcoding.
ISP-friendly P2P live streaming
Authors: Shen Zhijie , Zimmermann Roger
Published: February 2012

Peer-to-Peer (P2P) applications generate large amounts of Internet network traffic. The wide-reaching connectivity of P2P systems is creating resource inefficiencies for network providers. Recent studies have demonstrated that localizing cross-ISP (Internet service provider) traffic can mitigate this challenge. However, bandwidth sensitivity and display quality requirements complicate the ISP-friendly design for live streaming systems. To this date, although some prior techniques focusing on live streaming systems exist, the correlation between traffic localization and streaming quality guarantee has not been well explored. Additionally, the proposed solutions are often not easy to apply in practice.

In our presented work, we demonstrate that the cross-ISP traffic of P2P live streaming systems can be significantly reduced with little impact on the streaming quality. First, we analytically investigate and quantify the tradeoff between traffic localization and streaming quality guarantee, determining the lower bound of the inter-AS (autonomous system) streaming rate below which streaming quality cannot be preserved. Based on the analysis, we further propose a practical ISP-friendly solution, termed
IFPS
, which requires only minor changes to the peer selection mechanism and can easily be integrated into both new and existing systems. Additionally, the significant opportunity for localizing traffic is underscored by our collected traces from PPLive, which also enabled us to derive realistic parameters to guide our simulations. The experimental results demonstrate that
IFPS
reduces cross-ISP traffic from 81% up to 98% while keeping streaming quality virtually unaffected.
Quality of data delivery in peer-to-peer video streaming
Authors: Lou Xiaosong , Hwang Kai
Published: February 2012

QoS in a P2P video streaming system is evaluated in three stages: content generation, data delivery and video playback. We use jitter-free probability as the main performance metric to study
Quality of Data delivery
(QoD). A new model that incorporates both bandwidth and data availability of P2P network is proposed. Our model relies on a sharing factor that models data availability among all peers. We simulate on a minimalistic network to demonstrate how to apply the analytical model to design a P2P video streaming system with a very low jitter rate. Our simulation experimental results reveal that the lower bound on jitter-free probability is indeed effective to reflect the QoD of the entire system. Our model captures the impact of many design choices, including upload bandwidth limit, peer selection strategies, and video stream chunking schemes.
Providing hierarchical lookup service for P2P-VoD systems
Authors: Zhang Tieying , Cheng Xueqi , Lv Jianming , Li Zhenhua , Shi Weisong
Published: February 2012

Supporting random jump in P2P-VoD systems requires efficient lookup for the “best” suppliers, where “best” means the suppliers should meet two requirements:
content match
and
network quality match
. Most studies use a DHT-based method to provide content lookup; however, these methods are neither able to meet the network quality requirements nor suitable for VoD streaming due to the large overhead. In this paper, we propose Mediacoop, a novel hierarchical lookup scheme combining both content and quality match to provide random jumps for P2P-VoD systems. It exploits the
play position
to efficiently locate the candidate suppliers with required data (content match), and performs refined lookup within the candidates to meet quality match. Theoretical analysis and simulation results show that Mediacoop is able to achieve lower jump latency and control overhead than the typical DHT-based method. Moreover, we implement Mediacoop in a BitTorrent-like P2P-VoD system called CoolFish and make optimizations for such “total cache” applications. The implementation and evaluation in CoolFish show that Mediacoop is able to improve user experiences, especially the jump latency, which verifies the practicability of our design.
A Reconfigurable PLA Architecture for Nanomagnet Logic
Authors: Crocker Michael , Niemier Michael , Hu X. Sharon
Published: February 2012

In order to continue the performance and scaling trends that we have come to expect from Moore’s Law, many emergent computational models, devices, and technologies are actively being studied to either replace or augment CMOS technology. Nanomagnet Logic (NML) is one such alternative. NML operates at room temperature, it has the potential for low power consumption, and it is CMOS compatible. In this aricle, we present an NML programmable logic array (PLA) based on a previously proposed reprogrammable quantum-dot cellular automata PLA design. We also discuss the fabrication and simulation validation of the circuit structures unique to the NML PLA, present area, energy, and delay estimates for the NML PLA, compare the area of NML PLAs to other reprogrammable nanotechnologies, and analyze how architectural-level redundancy will affect performance and defect tolerance in NML PLAs. We will use results from this study to shape a concluding discussion about, which architectures appear to be most suitable for NML.
Modeling and Designing for Accuracy and Energy Efficiency in Wireless Electroencephalography Systems
Authors: Tolbert Jeremy R. , Kabali Pratik , Brar Simeranjit , Mukhopadhyay Saibal
Published: February 2012

Remote wireless monitoring of physiological signals has emerged as a key enabler for biotelemetry and can significantly improve the delivery of healthcare. Improving the energy efficiency and battery lifetime of the monitoring units without sacrificing the acquired signal quality is a key challenge in large-scale deployment of bioelectronic systems for remote wireless monitoring. In this article, we present a design methodology for accuracy aware, energy efficient wireless monitoring of electroencephalography (EEG) data. The proposed design performs a real-time accuracy energy trade-off by controlling the volume of transmitted data based on the information content in the EEG signal. We consider the effect of different system parameters in order to design an optimal system. We analyze the impact of noise of the wireless channel. Our analysis shows that the proposed system design approach can provide up to 10X energy savings in a 32 channel wireless EEG system with minimal impact on the monitored EEG signal accuracy.
Design Considerations for Multilevel CMOS/Nano Memristive Memory
Authors: Manem H. , Rajendran J. , Rose G. S.
Published: February 2012

With technology migration into nano and molecular scales several hybrid CMOS/nano logic and memory architectures have been proposed that aim to achieve high device density with low power consumption. The discovery of the memristor has further enabled the realization of denser nanoscale logic and memory systems by facilitating the implementation of multilevel logic. This work describes the design of such a multilevel nonvolatile memristor memory system, and the design constraints imposed in the realization of such a memory. In particular, the limitations on load, bank size, number of bits achievable per device, placed by the required noise margin for accurately reading and writing the data stored in a device are analyzed. Also analyzed are the nondisruptive read and write methodologies for the hybrid multilevel memristor memory to program and read the memristive information without corrupting it. This work showcases two write methodologies that leverage the best traits of memristors when used in either linear (low power) or nonlinear drift (fast speeds) modes. The system can therefore be tailored depending on the required performance parameters of a given application for a fast memory or a slower but very energy-efficient system. We propose for the first time, a hybrid memory that aims to incorporate the area advantage provided by the utilization of multilevel logic and nanoscale memristive devices in conjunction with CMOS for the realization of a high density nonvolatile multilevel memory.
Highly acyclic groups, hypergraph covers, and the guarded fragment
Authors: Otto Martin
Published: February 2012

We construct finite groups whose Cayley graphs have large girth even with respect to a discounted distance measure that contracts arbitrarily long sequences of edges from the same color class (subgroup), and only counts transitions between color classes (cosets). These groups are shown to be useful in the construction of finite bisimilar hypergraph covers that avoid any small cyclic configurations. We present two applications to the finite model theory of the guarded fragment: a strengthening of the known finite model property for GF and the characterization of GF as the guarded bisimulation invariant fragment of first-order logic in the sense of finite model theory.
Gem #80
Authors: Chapman Rod
Published: February 2012

Ada Gem #80 --- This Gem covers a topic that I recently encountered while working on a crypto algorithm in SPARK: how to use Ada's predefined shift and rotate functions with modular types from a SPARK program.
Gem #82
Authors: Moy Yannick
Published: February 2012

Ada Gem #82 --- The strong type system in Ada makes it quite convenient to check at compile time that certain security properties are verified, for example that a tainted value is not used where a trusted one is expected, or that data is properly validated before being used in a sensitive context (think of SQL injection attacks). In this series of two Gems, we present short examples of how this might be done. The first Gem discusses how to handle tainted data.
Multicriteria Optimization Model for the Study of the Efficacy of Skin Antiaging Therapy
Authors: Crişan Maria , Cappare Guido , Neamţiu Luciana , Chiorean Ioana , Lupşa Liana , Crişan Diana , Badea Radu
Published: February 2012

The evolution of the cutaneous structure after topical treatment with P63 antiaging complex, assessed with high frequency ultrasound, is studied by means of multicriteria optimization model. Due to the fact that the impact of the treatment may influence the quality of life, a medical index which measures, from this point of view, the efficacy of the treatment is given, also taking into account medical and economical aspects.
Natural Breeding Places for Phlebotomine Sand Flies (Diptera: Psychodidae) in a Semiarid Region of Bahia State, Brazil
Authors: Sangiorgi Bruno , Miranda Daniel Neves , Oliveira Diego Ferreira , Santos Edivaldo Passos , Gomes Fernanda Regis , Santos Edna Oliveira , Barral Aldina , Miranda José Carlos
Published: February 2012

Few microhabitats have been previously identified as natural breeding places for phlebotomine sand flies so far, and little is known about the influence of climate variables in their density. The present study was conducted in a dry region with a semiarid climate, where visceral leishmaniasis occurs in humans and dogs. The occurrence of breeding places in specific microhabitats was investigated in soil samples collected from five houses, which were also the location used for sampling of adults. All the microhabitats sampled by our study were identified as natural breeding places due to the occurrence of immature forms of sand flies. On a weekly basis, the number of adult sand flies captured was positively correlated with the mean temperature from preceding weeks. These results, in addition to promoting an advance in the knowledge of sand flies biology, may furnish a tool for optimizing the control of the sand flies, by indicating the most suitable periods and microhabitats for the application of insecticides.
Technical Considerations in Rehabilitation of an Edentulous Total Glossectomy Patient
Authors: Bhirangi Pravin , Somani Priyanka , Dholam K. P. , Bachher Gurmeet
Published: February 2012

The technician by virtue of his profession plays an important role in fabricating silicone tongue prosthesis for a total glossectomy patient. The technician, with his skills and specialized knowledge in handling material, plays a valuable role as a member of the oncology team. A patient with total glossectomy can be rehabilitated by silicone tongue prosthesis as an aid to improve his speech and swallowing. This paper describes the technical steps involved in fabricating a silicone tongue prosthesis for an edentulous total glossectomy patient.
Adaptive Noise Reduction of Scintigrams with a Wavelet Transform
Authors: Ogawa Koichi , Sakata Masahiko , Li Yu
Published: February 2012

The aim of this study was to eliminate the effect of Poisson noise in scintigrams with a wavelet thresholding method. We developed a new noise reduction method with a wavelet transform. The proposed method was a combination of the translation-invariant denoising method and our newly introduced denoising filter which was applicable for Poisson noise. To evaluate the validity of our proposed method, phantom images and scintigrams were used. The results with the phantom images showed that our method was better than conventional methods in terms of the peak signal-to-noise ratio by 3 dB. Quality of the scintigrams processed with our method was better than that with the conventional methods in terms of reducing Poisson noise while preserving edge components. The results demonstrated that the proposed method was effective for the reduction of Poisson noise in scintigrams.
Pharmacokinetic Interactions between the Hormonal Emergency Contraception, Levonorgestrel (Plan B), and Efavirenz
Authors: Carten Monica L. , Kiser Jennifer J. , Kwara Awewura , Mawhinney Samantha , Cu-Uvin Susan
Published: February 2012

Objectives. Compare the Plan B levonorgestrel (LNG) area under the concentration- time curve (AUC12) prior to and with efavirenz (EFV).Design. Prospective, open-label, single-arm, equivalence study.Methods. Healthy HIV-negative subjects underwent 12 hr intensive pharmacokinetic (PK) sampling following single dose LNG alone and after 14 days of EFV. Geometric means, Geometric Mean Ratios, and 90% confidence intervals (CI) are reported for PK Parameters.T-tests were utilized. Clinical parameters and liver function tests (LFTs) were assessed.Results. 24 women enrolled and 21 completed the study. With EFV, LNG AUC12was reduced 56% (95% CI: 49%, 62%) from 42.9 to 17.8 ng*hr/mL, and maximum concentration (Cmax⁡) was reduced 41% (95% CI: 33%, 50%) from 8.4 to 4.6 ng/mL. LNG was well tolerated with no grade 3 or 4 treatment-related toxicities.Conclusions. EFV significantly reduced LNG exposures. Higher LNG doses may be required with EFV. These results reinforce the importance of effective contraception in women taking EFV.
Novel Complex Polymers with Carbazole Functionality by Controlled Radical Polymerization
Authors: Nakabayashi Kazuhiro , Mori Hideharu
Published: February 2012

This review summarizes recent advances in the design and synthesis of novel complex polymers with carbazole moieties using controlled radical polymerization techniques. We focus on the polymeric architectures of block copolymers, star polymers, including star block copolymers and miktoarm star copolymers, comb-shaped copolymers, and hybrids. Controlled radical polymerization ofN-vinylcarbazole (NVC) and styrene and (meth)acrylate derivatives having carbazole moieties is well advanced, leading to the well-controlled synthesis of complex macromolecules. Characteristic optoelectronic properties, assembled structures, and three-dimensional architectures are briefly introduced.
Mie Plasmons: Modes Volumes, Quality Factors, and Coupling Strengths (Purcell Factor) to a Dipolar Emitter
Authors: Colas des Francs G. , Derom S. , Vincent R. , Bouhelier A. , Dereux A.
Published: February 2012

Using either quasistatic approximation or exact Mie expansion, we characterize the localized surface plasmons supported by a metallic spherical nanoparticle. We estimate the quality factorQnand define the effective volumeVnof thenth mode in such a way that coupling strength with a neighbouring dipolar emitter is proportional to the ratioQn/Vn(Purcell factor). The role of Joule losses, far-field scattering, and mode confinement in the coupling mechanism is introduced and discussed with simple physical understanding, with particular attention paid to energy conservation.
Possible Involvement of Smad Signaling Pathways in Induction of Odontoblastic Properties in KN-3 Cells by Bone Morphogenetic Protein-2: A Growth Factor to Induce Dentin Regeneration
Authors: Washio Ayako , Kitamura Chiaki , Morotomi Takahiko , Terashita Masamichi , Nishihara Tatsuji
Published: February 2012

We examined the effects of bone morphogenetic protein-2 (BMP-2) on growth, differentiation, and intracellular signaling pathways of odontoblast-like cells, KN-3 cells, to clarify molecular mechanisms of odontoblast differentiation during pulp regeneration process. After treatment with BMP-2, the cell morphology, growth, alkaline phosphatase (ALP) activity, and the activation and expression of BMP-induced intracellular signaling molecules, such as Smad1/5/8 and Smad6/7, as well as activities of dentin sialoprotein (DSP) and dentin matrix protein 1 (DMP1), were examined. BMP-2 had no effects on the morphology, growth, or ALP activity of KN-3 cells, whereas it induced the phosphorylation of Smad1/5/8 and expression of Smad6/7. BMP-2 also induced the expressions of DSP and DMP-1. Our results suggest that KN-3 cells may express an odontoblastic phenotype with the addition of BMP-2 through the activation of Smad signaling pathways.
Perinatal Gene-Gene and Gene-Environment Interactions on IgE Production and Asthma Development
Authors: Chang Jen-Chieh , Wang Lin , Chen Rong-Fu , Liu Chieh-An
Published: February 2012

Atopic asthma is a complex disease associated with IgE-mediated immune reactions. Numerous genome-wide studies identified more than 100 genes in 22 chromosomes associated with atopic asthma, and different genetic backgrounds in different environments could modulate susceptibility to atopic asthma. Current knowledge emphasizes the effect of tobacco smoke on the development of childhood asthma. This suggests that asthma, although heritable, is significantly affected by gene-gene and gene-environment interactions. Evidence has recently shown that molecular mechanism of a complex disease may be limited to not only DNA sequence differences, but also gene-environmental interactions for epigenetic difference. This paper reviews and summarizes how gene-gene and gene-environment interactions affect IgE production and the development of atopic asthma in prenatal and childhood stages. Based on the mechanisms responsible for perinatal gene-environment interactions on IgE production and development of asthma, we formulate several potential strategies to prevent the development of asthma in the perinatal stage.
Amelioration of Glucose Control Mobilizes Circulating Pericyte Progenitor Cells in Type 2 Diabetic Patients with Microangiopathy
Authors: Fadini Gian Paolo , Mancuso Patrizia , Bertolini Francesco , de Kreutzenberg Saula , Avogaro Angelo
Published: February 2012

Chronic diabetic complications result from an imbalance between vascular damage and regeneration. Several circulating lineage-committed progenitor cells have been implicated, but no data are available on pericyte progenitor cells (PPCs). Based on the evidence that PPCs increase in cancer patients after chemotherapy, we explored whether circulating PPC levels are affected by glucose control in type 2 diabetic patients, in relation to the presence of chronic complications. We enumerated peripheral blood PPCs as Syto16+CD45−CD31−CD140b+ events by flow cytometry at baseline and after 3 and 6 months of glucose control by means of add-on basal insulin therapy on top of oral agents in 38 poorly controlled type 2 diabetic patients. We found that, in patients with microangiopathy (n=23), the level of circulating PPCs increased about 2 fold after 3 months and then returned to baseline at 6 months. In patients without microangiopathy (control group,n=15), PPCs remained fairly stable during the whole study period. No relationship was found between change in PPCs and macroangiopathy (either peripheral, coronary, or cerebrovascular). We conclude that glucose control transiently mobilizes PPCs diabetic patients with microangiopathy. Increase in PPCs may represent a vasoregenerative event or may be a consequence of ameliorated glucose control on microvascular lesions.
Role of Protein Biomarkers in the Detection of High-Grade Disease in Cervical Cancer Screening Programs
Authors: Brown Charlotte A. , Bogers Johnannes , Sahebali Shaira , Depuydt Christophe E. , De Prins Frans , Malinowski Douglas P.
Published: February 2012

Since the Pap test was introduced in the 1940s, there has been an approximately 70% reduction in the incidence of squamous cell cervical cancers in many developed countries by the application of organized and opportunistic screening programs. The efficacy of the Pap test, however, is hampered by high interobserver variability and high false-negative and false-positive rates. The use of biomarkers has demonstrated the ability to overcome these issues, leading to improved positive predictive value of cervical screening results. In addition, the introduction of HPV primary screening programs will necessitate the use of a follow-up test with high specificity to triage the high number of HPV-positive tests. This paper will focus on protein biomarkers currently available for use in cervical cancer screening, which appear to improve the detection of women at greatest risk for developing cervical cancer, including Ki-67,p16INK4a, BD ProEx C, and Cytoactiv HPV L1.
Hydrothermal Synthesis of β‐NaYF4:Yb, Er Nanocrystals with Upconversion Fluorescence Using Tetraethylene Pentamine as Chelating Ligand
Authors: Wu Suli , Ning Yanhui , Zhang Shufen
Published: February 2012

Novel chelating ligands are very significant for preparing nanocrystals with different morphologies and applications. In this paper, we directly introduced amine groups onto UCNPs by choosing a new chelating ligand tetraethylene pentamine (TEPA) to synthesis NaYF4:Yb, Er through hydrothermal method. The influences of rare earth concentration, the ratio of RE/TEPA, solvent composition, and reaction time on the morphology and fluorescence intensity of the as‐prepared NaYF4:Yb, Er samples were systematically investigated and discussed. Field emission scanning electron microscopy (FE‐SEM), powder X‐ray diffraction (XRD), and upconversion luminescence spectroscopy were used to characterize the product. It was found that rare earth concentration, ratio of RE/TEPA, solvent composition, and reaction time were all responsible for the luminescent intensity and morphology.
PrimaryCandida guilliermondiiInfection of the Knee in a Patient without Predisposing Factors
Authors: Lee Gun Woo , Kim Tae-Hun , Son Jung-Hwan
Published: February 2012

Isolated primary candidal infection of joint is extremely rare, with only a few reported cases. It occurs as a result of accidental implantations of fungus during traumatic procedures, such as surgery, and is usually reported in patients with predisposing factors such as immunosuppression, malignancy, and drug abuse. If left untreated, irreversible deformity and pain with severe osteoarticular destruction occur. Thus, early diagnosis and treatment are important. This paper presents a case of 72-year-old man with primaryC. guilliermondiiinfection of knee joint without predisposing factors and previous traumatic procedures, who was misdiagnosed with advanced degenerative osteoarthritis. Our case is the second case of primaryC. guilliermondiiarthritis of knee to be reported in the English-language literature and the first to be successfully treated with total knee arthroplasty following IV amphotericin B and oral fluconazole. Primary candidal infection of joint is generally asymptomatic or involves only mild pain and swelling in the affected knee. Thus, although the majority of knee joint infections are of a pyogenic or tuberculous origin, if a patient complains of mild pain and swelling in the knee and has mild signs of infection, the possibility of fungal infection should be considered.
Quantitative Assessment of99mTc-Depreotide Uptake in Oesophageal Cancer and Precursor Conditions and Its Reflection in Immunohistochemically Detected Somatostatin Receptors
Authors: Herlin Gunnar , Lundell Lars , Öst Åke , Aspelin Peter , Svensson Leif , Axelsson Rimma
Published: February 2012

Background. Somatostatin receptors (SSTRs) are over-expressed in several tumors making it possible for imaging with labelled SSTR. A previous study showed feasibility to image oesophageal cancer with SSTR analogue99mTc-depreotide.Purpose. (1) To investigate expression of the SSTRs in different types of esophageal carcinoma and (2) to correlate such an expression with99mTc-depreotide uptake in these lesions.Material and Methods. Total 28 patients (17 with esophageal cancer and 11 with Barrett’s esophagus) were examined with99mTc-depreotide scintigraphy. The SSTR2A, SSTR2B, SSTR3, and SSTR5 were analyzed immunohistochemically in the lesion samples.Results. Among the patients with adenocarcinoma 10/11 expressed different amounts of SSTRs, while SSTRs were absent in 5/6 patients with Squamous cell carcinoma (Sqcc). There was no correlation neither between the99mTc-depreotide uptake and the amount of SSTRs nor between the amount of SSTRs and differentiation grade of the tumor.Conclusions. (1) SSTRs are expressed in esophageal carcinoma and more abundantly so in adenocancer specimens; (2) in vivo99mTc-depreotide uptake does not obviously correlate with the immunohistochemically detection of SSTRs of different subtypes in esophageal carcinoma.
Recombinant Expression and Characterization of Human and Murine ACE2: Species-Specific Activation of the Alternative Renin-Angiotensin-System
Authors: Poglitsch Marko , Domenig Oliver , Schwager Cornelia , Stranner Stefan , Peball Bernhard , Janzek Evelyne , Wagner Bettina , Jungwirth Helmut , Loibner Hans , Schuster Manfred
Published: February 2012

Angiotensin-converting enzyme 2 (ACE2) is a monocarboxypeptidase of the renin-angiotensin-system (RAS) which is known to cleave several substrates among vasoactive peptides. Its preferred substrate is Angiotensin II, which is tightly involved in the regulation of important physiological functions including fluid homeostasis and blood pressure. Ang 1–7, the main enzymatic product of ACE2, became increasingly important in the literature in recent years, as it was reported to counteract hypertensive and fibrotic actions of Angiotensin II via the MAS receptor. The functional connection of ACE2, Ang 1–7, and the MAS receptor is also referred to as the alternative axis of the RAS. In the present paper, we describe the recombinant expression and purification of human and murine ACE2 (rhACE2 and rmACE2). Furthermore, we determined the conversion rates of rhACE2 and rmACE2 for different natural peptide substrates in plasma samples and discovered species-specific differences in substrate specificities, probably leading to functional differences in the alternative axis of the RAS. In particular, conversion rates of Ang 1–10 to Ang 1–9 were found to be substantially different when applying rhACE2 or rmACE2in vitro. In contrast to rhACE2, rm ACE2 is substantially less potent in transformation of Ang 1–10 to Ang 1–9.