bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical and photoelectrical properties of CdSxSe1–xfilms produced by screen‐printing technology
Authors: Tivanov M. , Ostretsov E. , Drozdov N. , Survilo L. , Fedotov A. , Trofimov Yu. , Mazanik A.
Published: April 2007

In this paper the optical and photoelectrical properties of CdSxSe1–xfilms prepared using the screen‐printing and sintering technique, were studied. CdCl2was used both as a sintering flux and as a doping agent. CuCl was also used as a doping agent. The temperatures and times of preparation varied in the range of 500–600 °C and 5–60 min, respectively. The as‐prepared films were characterized by the scanning electron microscopy, micro‐probe X‐Ray analysis, photoluminescence and photoconductance methods. Our investigations have shown that photoresponse of the CdSxSe1–xfilms prepared by a screen‐printing method can be suitable for the production of large‐area photosensitive devices. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Large‐Scale, Hot‐Filament‐Assisted Synthesis of Tungsten Oxide and Related Transition Metal Oxide Nanowires
Authors: Thangala Jyothish , Vaddiraju Sreeram , Bogale Rahel , Thurman Ryan , Powers Trevor , Deb Biswapriya , Sunkara Mahendra K.
Published: April 2007

A scalable and versatile method for the large‐scale synthesis of tungsten trioxide nanowires and their arrays on a variety of substrates, including amorphous quartz and fluorinated tin oxide, is reported. The synthesis involves the chemical‐vapor transport of metal oxide vapor‐phase species using air or oxygen flow over hot filaments onto substrates kept at a distance. The results show that the density of the nanowires can be varied from 106–1010 cm−2 by varying the substrate temperature. The diameter of the nanowires ranges from 100–20 nm. The results also show that variations in oxygen flow and substrate temperature affect the nanowire morphology from straight to bundled to branched nanowires. A thermodynamic model is proposed to show that the condensation of WO2 species primarily accounts for the nucleation and subsequent growth of the nanowires, which supports the hypothesis that the nucleation of nanowires occurs through condensation of suboxide WO2 vapor‐phase species. This is in contrast to the expected WO3 vapor‐phase species condensation into WO3 solid phase for nanoparticle formation. The as‐synthesized nanowires are shown to form stable dispersions compared to nanoparticles in various organic and inorganic solvents.
Structural vibrations and noise reduction by piezoelectric active control
Authors: Ghiringhelli G. L.
Published: April 2007

The present work describes a numerical procedure for the design of a piezoelectric active control system capable of reducing the acoustic emission from forced structural elements. The characterisation of the actively controlled structure is carried out through an integrated electro‐elastic Finite Element (FE) approach. Because of the possibility of using piezoelectric layers as self‐sensing actuators, a simple and effective collocated control technique is employed; within this framework different control laws are allowed by the use of external electric circuits implementing appropriate measurement conditioning. The acoustic pressure field around the vibrating structure is simulated by using a boundary elements method interfaced to the FE structural model through mobility matrices.
Energy principle and its application in conceiving controlled structures
Authors: Abovsky N. P.
Published: April 2007

The energy principle of structural control is proposed. Controlled structures are considered as automatic systems which include the energy source needed for control.
Fault tolerant structural control systems for civil engineering applications
Authors: Battaini M. , Dyke S. J.
Published: April 2007

The objective of this work is to experimentally examine some practical issues relating to the reliability and performance of active structural control systems. Using the newly constructed shaking table in the Department of Structural Mechanics at the University of Pavia, experiments were conducted employing an actively controlled, three story test structure. A DC‐motor based active mass driver system was used as the active control device. An H2/LQG controller based on acceleration feedback is applied to the system. The first objective of this work is to demonstrate the efficacy of the acceleration feedback control strategy. Next, two experiments are conducted with the goal of investigating fault tolerant control system design. In the first case, the occurence of a sensor failure is simulated experimentally, and the resulting controlled performance and robustness characteristics are assessed. The second set of tests is to evaluate the ability of the controller to reduce the structural responses when reduced information is available for control action determination. Both of these issues are important practical concerns in the design and implementation of a structural control system.
Experimental study of active control using neural networks
Authors: Chen H. M. , Qi G. Z. , Yang J. C. S. , Amini F.
Published: April 2007

Significant progress has been achieved in the active control of civil engineering structures in recent years. Although many control algorithms has been proposed, only few experiments in active structural control have been performed. In this paper, active structural control experiments were carried out using a scaled model structure simulating a three‐story steel frame building. The model was subjected to a base motion on a shake table. A neural network based controller was implemented to control the response of the structure. This trained neural controller was implemented to control the response of the structure. It is experimentally verified that the neural network is able to generalized to new inputs, i.e. a properly trained neural network is capable of providing sensible outputs when presented with input data that has never been used during training. Results from this experimental study indicate great promise for the control of civil engineering structures under dynamic loadings using the artificial neural network controller.
Nonlinear decentralized active tendon control of cable‐stayed bridges
Authors: Magaña M. E. , Rodellar J.
Published: April 2007

A nonlinear decentralized active tendon controller that substantially reduces the magnitude of the vibrations of a segment of a cable‐stayed bridge induced by a seismic excitation is presented in this paper. The model used to represent the dynamic behaviour of the bridge takes into account the inherent nonlinearities due to the stay cables geometry. This is in contrast with traditional models used by previous designers of active controllers of cable‐stayed bridges, who assumed completely linear models. The proposed controller is comprised of a linear and a nonlinear part. Its performance is verified via digital computer simulation.
Input‐signal characterization for shaking‐tables
Authors: Casciati F. , Faravelli L. , Petrini L.
Published: April 2007

A large worldwide earthquake data‐bank is available for numerical and experimental response analyses of base‐excited structural systems. Most of these accelerograms are stored in their uncorrected form and this is appropriate and convenient since they must be differently processed for different engineering applications. Record processing is a necessary step toward the use of recorded data in numerical simulations: it deletes spurious low and high frequency content, introduced in detection, acquisition, storage and digitalization of the signal. Moving from numerical to experimental analyses, the testing machine acts as a filter and, hence, the processing could be no longer required. The paper tries to investigate this aspect.
Controlled structural systems: Design and reliability
Authors: Battaini M.
Published: April 2007

This paper is an extended summary of the dissertation presented by the author for the Ph.D degree in civil engineering at the University of Pavia.

The aim of the dissertation is the design and the experimental validation of an active control scheme, the simulation of possible real operating problems (such as sensor failures) and the reliability assessment of the active control system. The goal is to identify and discuss a scenario of possible problems the designer will meet in implementing an active control scheme.

The work consists of a preliminary theoretical part, necessary for the implementation of the active control system, an experimental activity on a suitably scaled structural model and a reliability analysis of the adopted active control system.
Design and implementation of a jet actuator for active structural control
Authors: Brambilla M.
Published: April 2007

In active control applications to civil engineering structures, large control forces are required, but the generation of such forces may render the active control implementation impractical.

To overcome this drawback, the actuator force can be supplied by the flow of compressed air: it applies a force to the jet supporting structure thanks to the principle of Momentum Preservation (Conservation). The air is stored in a tank and it flows towards a semi‐rigid pipe to the final actuator‐jets, simply realized as nozzles. The flow through each nozzle is controlled by an on‐off electro‐valve, and the system response is monitored by accelerometers.

The main achievement is that the resulting control system is indipendent of external energy supply, enough energy having been stored, as compressed air, in a tank. In this way the reliability of the control system is not affected by the availability of external electric power, that in case of earthquake can easily be interrupted.

While many studies have been made on pulse‐control methods, only a few have investigated the implementation of such nonlinear control schemes. The focus of this work is on the experimental investigation of some of the numerous practical issues one meets in the development of actuators based on mass‐ejection techniques.

A single degree of freedom system, i.e. a simple vertical cantiliver with a lumped mass at the top, is tested on a shaking‐table under different excitation time‐histories, and the efficiency of the controller is evaluated.
An optical fibre sensor for dynamic structural response monitoring
Authors: Abbiati P. , Casciati F. , Merlo S.
Published: April 2007

An optical fibre sensor for bridge monitoring is presented. It pursues the sensing of heavy traffic loads, and in particular vibration monitoring.

A simple intensity device is conceived; it is calibrated under laboratory static loading.

The paper reports and discusses the results of dynamic tests aimed at measuring the oscillations of a steel bar whose bottom end is fixed to a shaking‐table. The table is driven by a hydraulic actuator capable of providing an assigned horizontal movement of different amplitude and frequency content.
Optimization of the adhesion of fiber‐optic strain sensors embedded in cement matrices; a study into long‐term fiber strength
Authors: Habel Wolfgang R. , Bismarck Alexander
Published: April 2007

Fiber‐optic strain sensors to be used in materials research and for long‐term monitoring the state of chemically stressed concrete, e. g. sewer pipes, cooling towers, have to be intimately embedded in cement matrices. They should be coated with very thin alkaline‐resistant coatings. This is necessary to achieve a reliable strain transfer from the matrix to the fiber sensor.

In order to clarify possible ways to replace thick coatings, which are unstable in cement environment, optical fibers have been modified and investigated with regard to their chemical compatibility, their strength behavior after alkaline attacks and their adhesion behavior to the matrix. The surface state of differently treated optical fibers intended for embedding has been characterized; additional strength estimation of alkaline attacked fibers was carried out. All estimations have been compared with those of bare alkaline attacked fibers.

The real adhesion behavior was determined using the fiber push‐in test technique (indentation). Recent results suggest that fibers coated with very thin organic layers have remarkable adhesion properties. However, the fiber strength after exposing to alkaline pore solution (pH = 13.9) is worse than that of bare fibers. Optimum fiber/cement bond strength showed fibers, which were coated with a crosslinked polymer, produced in gas plasma.
Application of true linearization in stochastic quasi‐optimal control problems
Authors: Socha L. A.
Published: April 2007

The problem of quasi‐optimal linear feedback control laws for nonlinear systems with quadratic performance criteria under Gaussian white noise excitations is considered. To determine the quasi‐optimal control a modified version of standard iterative procedure is used, where three versions of statistical linearization methods and true linearization method were combined with the optimal control method for linear systems with the mean‐square criterion. The validity of this method is shown by analytical and numerical calculations for examples.
Modelling the response of an elastomeric base isolator
Authors: Faravelli L.
Published: April 2007

A producer of base isolation devices made available low damping elastomeric bearings in a size consistent with the shaking table facilities available at the Department of Structural Mechanics of the University of Pavia in Italy. The mass the shaking table can bear is 400 kg. This means that one base isolator is enough as vertical support, but more isolators would provide an excessive horizontal stiffness. Two further supports were realised by a steel‐teflon contact. It showed good sliding capability under a mass of 100 kg, while for the mass of 400 kg a significant friction effect was emphasised. The laboratory tests were able to identify the device behaviour by collecting absolute inertial force/relative displacement couples. The constitutive law is inferred by a genetic algorithm. This aspect is deeply investigated.
Active flap control of long suspension bridges
Authors: Hansen H. I. , Thoft‐Christensen P.
Published: April 2007

This article is an extended summary of a Ph.D. Thesis, see (Hansen, 1998). In the thesis theoretical and experimental effects of flap control on a bridge section are compared. Dynamics of long suspension bridges is summarized with special attention on the flutter phenomenom. The aerodynamic derivatives for a flat plate with flaps are derived based on the Theodorsen theory. Estimation of the flutter wind velocity is shown when both the Theodorsen method and the Air Material Command method are used. Three control algorithms are described, namely Classical Linear Optimal closed‐loop control, Instantaneous Optimal closed‐loop control and control with constant phase angles between the motion of the bridge section and the flap motions. Wind tunnel experiments are described and the experimental data are analysed. Finally the results of the wind tunnel experiments are compared to the theory.
The performance of HDRB devices in base isolation: A stochastic sensitivity analysis
Authors: Greco R. , Marano G. C. , Mezzina M.
Published: April 2007

In this paper the seismic response of base isolated structures with high damping laminated rubber bearings is evaluated. The analysis is based on a stochastic approach and the seismic acceleration is modelled through a Gaussian zero mean non stationary stochastic process. More precisely, the recent generalized Kanai‐Tajimi model proposed by Fan and Ahmadi for the El Centro 1940 N00W and Mexico City 1985 N90W earthquakes is used to preserve the non stationary amplitude and frequency characteristics of the seismic motion.

The non linear constitutive behaviour of the base isolator is represented by the hysteretic differential Bouc‐Wen model. The stochastic linearization method in the time domain is used to evaluate the statistical moments of the system response in the state space. The non linear differential equation of the response covariance matrix is solved by using an iterative procedure which at each step updates the coefficients of the equivalent linear system and searches for the solution of the response covariance matrix equation. To assess the accuracy of the results, these are compared with the non linear response obtained by using seismic accelerations generated with Monte Carlo simulation. Finally, the peaks of the system response variance are estimated and a sensitivity analysis is performed.
Analytic criteria for the stability of linear control systems with time delay
Authors: Breitung K.
Published: April 2007

The influence of time delay in linear control systems is often modeled by approximations. Here analytic criteria for determining the stability of linear differential delay systems are described. The characteristic function of such a system is a quasipolynomial, i.e. a polynomial Q(z) multiplied by powers of the exponential function exp(‐τz) plus another polynomial P(z). Using concepts of the theory of functions it has been shown that by evaluating a sequence of path integrals or the integral over the derivative of the logarithm of the characteristic function along the positive part of the imaginary axis it can be determined if the system is stable. As new result it is derived that by estimating the maximal modulus of the zeros of the characteristic function this can be reduced to the calculation of a path integral of this function over a finite contour.
Risk‐sensitive control for nonlinear flexible structures
Authors: Kovaleva Agnessa
Published: April 2007

The problem of controlling a noisy flexible system so as to prevent it from leaving a pregiven safe region covers a wide range of applications. This work proposes a new approach to the problem and extends risk‐sensitive control theory to nonlinear flexible systems. Risk‐sensitive control investigates the manner in which modification of the cost criteria in stochastic systems affects the associated optimal control and makes it more sensitive to undesirable outcomes. In the problem in question, the control goal is to counteract rare but large deviations from a prescribed mode of operation. The paper develops an approximate procedure allowing construction of near‐optimal control of a relatively simple structure. The leading order near‐optimal control is found as a stationary feedback with parameters dependent on the noise intensity in the small noise limit. Limiting control performance is estimated. Risk‐sensitive control against seismic excitations is considered as an application of the theory.
Quantification of serotonin 5‐HT1A receptors in humans with [11C](R)‐(−)‐RWAY: Radiometabolite(s) likely confound brain measurements
Authors: Zhang Xiang‐Yang , Yasuno Fumihiko , Zoghbi Sami S. , Liow Jeih‐San , Hong Jinsoo , Mccarron Julie A. , Pike Victor W. , Innis Robert B.
Published: April 2007

[11C](R)‐(−)‐RWAY has been shown to be a promising radioligand for imaging brain 5‐HT1A receptors with positron emission tomography in rodents and nonhuman primates. We now report the first use of [11C](R)‐(−)‐RWAY in six healthy human subjects, using kinetic brain imaging and serial arterial measurements of plasma parent radiotracer. At 80 min after radiotracer injection, activity ratios were about three for brain receptor‐rich regions compared with cerebellum. However, the washout from brain was unexpectedly slow relative to plasma clearance of the parent radiotracer. This disparity between brain and plasma activity was quantified with distribution volume calculated from increasingly truncated brain imaging data. In both receptor‐rich regions and cerebellum, distribution volumes were unstable and increased continuously from 90 to 150 min by about 30%. This increasing distribution volume was unlikely due to the variations or errors of plasma input at later time points, since a similar truncation of plasma time points from 150 to 90 min did not significantly affect the analysis of the brain data. When the metabolites of [11C](R)‐(−)‐RWAY in human and monkey were compared, a moderate lipophilic radiometabolite was present at a significantly higher percentage of total plasma radioactivity in human than in monkey. The relatively slow washout of activity from brain and the temporal instability of distribution volume likely reflect the accumulation of radiometabolite(s) in human brain. Although prior studies in rodents and nonhuman primates showed [11C](R)‐(−)‐RWAY to be a promising radiotracer, we suspect that a species difference in metabolism caused this serious deficiency in humans. Synapse 61:469–477, 2007. Published 2007 Wiley‐Liss, Inc.
Escalating dose, multiple binge methamphetamine regimen does not impair recognition memory in rats
Authors: Clark Robert E. , Kuczenski Ronald , Segal David S.
Published: April 2007

Rats exposed to methamphetamine (METH) in an acute high dose “binge” pattern have been reported to exhibit a persistent deficit in a novel object recognition (NOR) task, which may suggest a potential risk for human METH abusers. However, most high dose METH abusers initially use lower doses before progressively increasing the dose, only eventually engaging in multiple daily administrations. To simulate this pattern of METH exposure, we administered progressively increasing doses of METH to rats over a 14 day interval, then treated them with daily METH binges for 11 days. This treatment resulted in a persistent deficit in striatal dopamine (DA) levels of ∼20%. We then tested them in a NOR task under a variety of conditions. We could not detect a deficit in their performance in the NOR task under any of the testing conditions. These results suggest that mechanisms other than or additional to the decrement in striatal DA associated with an acute METH binge are responsible for the deficit in the NOR task, and that neuroadaptations consequential to prolonged escalating dose METH pretreatment mitigate against these mechanisms. Synapse 61:515–522, 2007. © 2007 Wiley‐Liss, Inc.
Patent and know‐how licensing: The U.S. and the European community in 1992
Authors: Tancer Robert S. , Nejdawi Bashar
Published: April 2007

U.S. and EC firms transferring patented and know‐how technology in the nineties will not have major substantive adjustments due to the many similarities in the development of their respective laws and policies. Those differences that will require understanding will more likely originate from form, principally the extensive use of Commission Regulations in the EC that have no counterpart in the U.S.
The impact of changes in bank secrecy laws
Authors: Bergevin Peter M.
Published: April 2007

Banks should be able to afford their customers a certain degree of privacy, but a number of disclosure‐limit laws have been passed to thwart criminals who engage in such practices as money laundering. The legitimate investor who needs a degree of financial privacy must examine banking strategies carefully.
How to analyze foreign financial statements
Authors: Krahmer Elizabeth M.
Published: April 2007

To assess the financial performance and health of foreign competitors, or a proposed foreign acquisition, U.S. executives need to know how to assess foreign financial information and must understand the significant accounting differences among countries.
A tax trap for non‐citizens and their spouses
Authors: Holleman Wilbur J. , Norman William K.
Published: April 2007

Non‐U.S. citizens who are married to Americans are in danger of falling into a nasty tax disaster unless they do the proper estate planning ahead of time.
Four steps to exporting success
Authors: Hojjat Mehdi
Published: April 2007

True, selling to Malaysia can be as easy as selling to Arizona—provided you have your export plan in place. Planning is important for any business interested in overseas markets, but essential for the new‐to‐export company if it is to have a smooth and orderly entry into world markets.
Focusing on quality in the pacific rim
Authors: D'O'Brian Joseph
Published: April 2007

American companies that want to sell to the Pacific Rim are missing the point if they focus on pricing or variety. Quality is the key issue—and Japan is the key competitor.
Micro and macro socioeconomic changes in the USSR
Authors: Chernina Natalia
Published: April 2007

The vast changes in the Soviet economic structure did not begin with the recent failed coup; they have been progressing for several years. Despite the fact that everyone agrees on the importance of economic reform, it has been a slow struggle—partly because of individual expectations.
Antitrust pitfalls for doing business in the post‐1992 EC
Authors: Scheibal William J.
Published: April 2007

Despite the potential that the European Community holds for American companies, those seeking to do business in the EC should be aware of the potential difficulties that may be created by EC antitrust laws. A knowledge of the EC antitrust laws can keep companies from making costly mistakes when marketing, producing, or importing and exporting goods.
Present barriers to technology transfer: U.S. to Eastern Europe versus U.S. to Mexico
Authors: Dean Carol Carloson , Master Jane Le
Published: April 2007

Technological innovations offer much promise for widespread technology transfer on a global basis. Yet, without taking social, economic, or political considerations into account, companies cannot transfer technology as effectively. Of particular importance is understanding technology transfer vis‐à‐vis emerging markets such as Mexico and Eastern Europe.
The free trade agreement between Mexico and the United States: Financing and investing considerations
Authors: Bergevin Peter M.
Published: April 2007

Enactment of a free trade agreement between Mexico and the United States will probably increase trade between the two countries. Direct foreign investment and capital market transactions will play a critical role in financing the ever‐growing mutual economic interdependence of the two countries. The sustained growth of the Mexican economy is a critical factor in a successful long‐term trading relationship. To a certain extent, Mexico's economic health is dependent on U.S. investment in Mexico and in Mexican companies. This article examines certain investing and financing considerations regarding U.S. investment in Mexico. The intent of this study is to make individuals, on both sides of the border, aware of the financial environment in which they are operating. This, in turn, should enhance the opportunities for successful cross‐border business activities. © 1993 John Wiley & Sons, Inc.
Understanding Chinese and Japanese negotiating styles
Authors: Chen Min
Published: April 2007

The purpose of this article is to explain various aspects of Chinese and Japanese business negotiating styles. Both the Chinese and Japanese have a reputation for being tough negotiators, but their strategies and tactics are neither unpredictable nor insurmountable. Although they share similar cultural traditions, they do have some notable differences. This article begins with an analysis of general perceptions of the Chinese and Japanese on negotiations, and then goes through different stages of the formal negotiating process while focusing on some of the tactics used either commonly or respectively by the Chinese and Japanese. It ends with a discussion on conflict management. Throughout the article, similarities and differences between the Chinese and Japanese are highlighted. The article presents a conceptual framework for understanding and comparing Chinese and Japanese negotiating styles. © 1993 John Wiley & Sons, Inc.
Abnormal expression of ENaC and SGK1 mRNA induced by dietary sodium in Dahl salt‐sensitively hypertensive rats
Authors: Aoi Wataru , Niisato Naomi , Sawabe Yukinori , Miyazaki Hiroaki , Tokuda Shinsaku , Nishio Kyosuke , Yoshikawa Toshikazu , Marunaka Yoshinori
Published: April 2007

Epithelial sodium channel (ENaC) plays a crucial role in controlling sodium reabsorption in the kidney keeping the normal blood pressure. We previously reported that the expression of ENaC mRNA in the kidney of Dahl salt‐sensitive (DS) rats was abnormally regulated by aldosterone, however it is unknown if dietary sodium affects the expression of ENaC and serum and glucocorticoid‐regulated kinase 1 (SGK1), which plays an important role in ENaC activation, in DS rats. In the present study, we investigated whether dietary sodium abnormally affects the expression of ENaC and SGK1 mRNA in DS rats. DS and Dahl salt‐resistant (DR) rats (8 weeks old) were divided into three different groups, respectively: (1) low sodium diet (0.005% NaCl), (2) normal sodium diet (0.3% NaCl), and (3) high sodium diet (8% NaCl). The high sodium diet for 4 weeks in DS rats elevated the systolic blood pressure, but did not in any other groups. The expression of α‐ENaC mRNA in DS rats was abnormally increased by high sodium diet in contrast to DR rats, while it was normally increased by low sodium diet in DS rats similar to DR rats. The expression of β‐ and γ‐ENaC mRNA in DS rats was also abnormally increased by high sodium diet unlike DR rats. The expression of SGK1 mRNA was elevated by high sodium diet in DS rats, but it was decreased in DR rats. These observations indicate that the expression of ENaC and SGK1 mRNA is abnormally regulated by dietary sodium in salt‐sensitively hypertensive rats, and that this abnormal expression would be one of the factors causing salt‐sensitive hypertension.
Tunneling nanotubes: A new route for the exchange of components between animal cells
Authors: Gerdes Hans-Hermann , Bukoreshtliev Nickolay V. , Barroso João F.V.
Published: April 2007

Recently, highly sensitive nanotubular structures mediating membrane continuity between mammalian cells have been discovered. With respect to their peculiar architecture, these membrane channels were termed tunneling nanotubes (TNTs). TNTs could form de novo between animal cells leading to the generation of complex cellular networks. They have been shown to facilitate the intercellular transfer of organelles as well as, on a limited scale, of membrane components and cytoplasmic molecules. It has been proposed that TNTs represent a novel and general biological principle of cell‐to‐cell communication and it becomes increasingly apparent that they fulfill important functions in the physiological processes of multicellular organisms.
Presence of bone marrow micrometastasis is associated with different recurrence risk within molecular subtypes of breast cancer
Authors: Naume Bjørn , Zhao Xi , Synnestvedt Marit , Borgen Elin , Russnes Hege Giercksky , Lingjærde Ole Christian , Strømberg Maria , Wiedswang Gro , Kvalheim Gunnar , Kåresen Rolf , Nesland Jahn M. , Børresen-Dale Anne-Lise , Sørlie Therese
Published: April 2007

Expression profiles of primary breast tumors were investigated in relation to disseminated tumor cells (DTCs) in bone marrow (BM) in order to increase our understanding of the dissemination process. Tumors were classified into five pre‐defined molecular subtypes, and presence of DTC identified (at median 85 months follow‐up) a subgroup of luminal A patients with particular poor outcome (p=0.008). This was not apparent for other tumor subtypes. Gene expression profiles associated with DTC and with systemic relapse for luminal A patients were identified. This study suggests that DTC in BM differentially distinguishes clinical outcome in patients with luminal A type tumors and that DTC‐associated gene expression analysis may identify genes of potential importance in tumor dissemination.
Anatomic and spiral computed tomographic study of the genial tubercles for genioglossus advancement
Authors: Kai Yin Shan , Liang Yi Hong , Ying Lu Wen , Guan Jian , Min Wu Hong , Yu Cao Zhen , Zhen Yu Dong , Yan Huang Yan , Wu Chun Gen
Published: April 2007

Objective

To measure and compare Chinese mandibulaö genial tubercles measured anatomically and with computed tomography (CT).

Study Design And Setting

Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods.

Results

The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 ± 0.71, 6.98 ± 1.35, 11.95 ± 1.59, 11.08 ± 2.05, and 16.91 ± 2.30 mm from anatomic measurements and 6.17 ± 0.71, 7.01 ± 1.13, 12.19 ± 1.64, 10.41 ± 1.55, and 15.73 ± 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated.

Conclusion

Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement.

Significance

This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy.
Biofilm formation in cochlear implants with cochlear drug delivery channels in an in vitro model
Authors: Johnson Trey A. , Loeffler Kimberly A. , Burne Robert A. , Jolly Claude N. , Antonelli Patrick J.
Published: April 2007

Background

Cochlear implant (CI) drug delivery (DD) may improve electrophysiological outcomes, but it may also increase the risk of suppurative complications. The aim of this study was to evaluate the development of bacterial biofilms on DD ports when subjected to varying types of penetration.

Methods

Silastic models were constructed to represent CIs with a DD channel, with an intact port, a widely opened port, a noncoring needle penetrating the port, and a noncoring needle removed from the port. CIs were exposed to a culture of a biofilm‐forming strain of Staphylococcus aureus for 5 days. Biofilm formation was assessed with quantitative bacterial counts (after eliminating planktonic bacteria) and scanning electron microscopy.

Results

Bacterial counts were significantly higher in CIs with widely fenestrated ports than all other port conditions (P = 0.0003).

Conclusions

Biofilm formation may be minimized on CIs with DD by using fine, noncoring needles and limiting the duration of port penetration.
The clinical behavior of isolated sphenoid sinusitis
Authors: Gilony Dror , Talmi Yoav P. , Bedrin Lev , Ben‐Shosan Yosef , Kronenberg Jona
Published: April 2007

Objective

We sought to study the clinical behavior and treatment outcome of isolated sphenoid sinusitis (ISS).

Study Design and Setting

We conducted a retrospective study of patients diagnosed with ISS in a tertiary medical center over 20 years.

Results

Of 72 patients with ISS, 79 percent had acute symptoms, 15 percent had chronic symptoms, and 6 percent had incidental radiological findings. Fifteen percent were children. Most patients were diagnosed between January and April (P < 0.01), and increasing incidence was noted over the years (P < 0.001). Headache was the most common presenting symptom (85%). Chronic patients complained also of nasal symptoms (82%). Six patients had a major complication of sinusitis (none of them were children), and two patients died. Immunocompromised patients had more major complications (P ≤ 0.001) and increased mortality (P ≤ 0.01).

Conclusion

Most patients need conservative treatment alone. However, life‐threatening complications are not infrequent. Close observation and early surgical intervention, if needed, provide the mainstay of treatment.

Significance

This is the first large series that focuses on the clinical behavior, complications, and treatment of ISS.
Threshold shift: Effects of cochlear implantation on the risk of pneumococcal meningitis
Authors: Wei Benjamin P. C. , Shepherd Robert K. , Robins‐Browne Roy M. , Clark Graeme M. , O'Leary Stephen J.
Published: April 2007

Objectives

The study goals were to examine whether cochlear implantation increases the risk of meningitis in the absence of other risk factors and to understand the pathogenesis of pneumococcal meningitis post cochlear implantation.

Study Design and Setting

Four weeks following surgery, 54 rats (18 of which received a cochleostomy alone, 18 of which received a cochleostomy and acute cochlear implantation using standard surgical techniques, and 18 of which received a cochlear implant) were infected with Streptococcus pneumoniae via three different routes of bacterial inoculation (middle ear, inner ear, and intraperitoneal) to represent all potential routes of bacterial infection from the upper respiratory tract to the meninges.

Results

The presence of a cochlear implant reduced the threshold of bacteria required to cause pneumococcal meningitis from all routes of infection in healthy animals.

Conclusion

The presence of a cochlear implant increases the risk of pneumococcal meningitis regardless of the route of bacterial infection.

Significance

Early detection and treatment of pneumococcal infection such as otitis media may be required, as cochlear implantation may lead to a reduction of infectious threshold for meningitis.
Extracts from The Cochrane Library: Allergen injection immunotherapy for seasonal allergic rhinitis (review)
Authors: Burton Martin J. , Krouse John H. , Rosenfeld Richard M.
Published: April 2007

The “Cochrane Corner” is a quarterly section in the journal that highlights systematic reviews relevant to otolaryngology–head and neck surgery, with invited commentary to highlight implications for clinical decision making. This installment features a Cochrane Review entitled “Allergen injection immunotherapy for seasonal allergic rhinitis,” which shows a low risk of adverse events plus a significant reduction in symptom scores and medication use.
Undernutrition in early life and body composition of adolescent males from a birth cohort study
Authors: Gigante Denise P. , Victora Cesar G. , Horta Bernardo L. , Lima Rosângela C.
Published: April 2007

The evidence for an association between poor nutrition in early life and subsequent obesity is inconclusive. In the present study, we investigated the associations between stunting, wasting and underweight at 2 and 4 years of age, and body composition in adolescence in male subjects studied since birth. The 1982 Pelotas Birth Cohort Study included all children born in maternity hospitals and living in the urban area of the city of Pelotas, Southern Brazil. All males born in 1982 were legally required to enlist in the army between January and April 2000. We were thus able to track 2250 subjects in 2000 (78·9 % of the original cohort). Anthropometric measurements were collected in 1984 and 1986, and body composition was assessed in 2000. In the present analysis, we used as predictors the nutritional indices height-for-age, weight-for-height and weight-for-age presented in six categories. Outcomes included fat, lean and body mass indices and fat:lean mass ratio, derived from anthropometric and bioimpedance measurements. ANOVA and linear regression were used in the analyses to adjust for confounding. All predictors were positively associated with fat and body mass indices. Height-for-age Z score at age 2 or 4 years was not associated with lean mass index, but all other predictors were associated. Fat:lean mass ratio was associated only with weight-for-height Z score. Our results suggest that undernutrition is not a risk factor for overweight and obesity in our population and may partially protect against fatness in adolescence.
Plasma concentrations of carotenoids and vitamin C are better correlated with dietary intake in normal weight than overweight and obese elderly subjects
Authors: Vioque Jesús , Weinbrenner Tanja , Asensio Laura , Castelló Adela , Young Ian S. , Fletcher Astrid
Published: April 2007

Carotenoid and vitamin C intakes, assessed by FFQ, have been positively associated with plasma concentrations in different populations. However, the influence of BMI on these associations has not been explored in detail. We explored in a cross-sectional study the relation between dietary carotenoid and vitamin C intakes, using a 135-item FFQ, with their plasma concentrations by BMI categories in 252 men and 293 women, 65 years and older. For men and women combined, significant (P < 0·05) Pearson correlations were observed between energy-adjusted dietary intakes and plasma concentrations (carotenoids adjusted for cholesterol) for: α-carotene 0·21, β-carotene 0·19, lycopene 0·18, β-cryptoxanthin 0·20 and vitamin C 0·36. Multiple linear regression analyses showed that the intake of carotenoids and vitamin C were significant predictors of their respective plasma concentration (P < 0·01), and that BMI was inversely associated with plasma concentration of carotenoids (P ≤ 0·01) but not with plasma vitamin C. In addition, we observed significant interactions between BMI and the intakes of α-carotene and lutein + zeaxanthin, and to a lower extent β-carotene, suggesting that these intakes in subjects with high BMI were not good predictors of their plasma concentration. The present data suggest that plasma carotenoids and vitamin C may be good markers of dietary intake in elderly subjects, but not so for α-carotene, β-carotene and lutein + zeaxanthin in obese subjects.
The minor allele of the PPARγ2 Pro12Ala polymorphism is associated with lower postprandial TAG and insulin levels in non-obese healthy men
Authors: Helwig Ulf , Rubin Diana , Kiosz Julia , Schreiber Stefan , Fölsch Ulrich R. , Nothnagel Michael , Döring Frank , Schrezenmeir Jürgen
Published: April 2007

The PPARγ Pro12Ala polymorphism has been associated in several studies with a decreased risk of obesity, type 2 diabetes and insulin resistance. Weak hints are available about the influence of PPARγ Pro12Ala on postprandial metabolism. In 708 men, aged 45 to 65 years the PPARγ2 Pro12Ala genotypes were determined and postprandial TAG, insulin, glucose and NEFA after a standardized mixed fat meal and insulin and glucose after a glucose load (oral glucose tolerance test; OGTT) were assessed. Using the total sample, we did not find a significant impact of the genotype on the postprandial metabolism. In the subgroup with BMI < 30 kg/m2, fasting and postprandial TAG and insulin levels as well as homeostasis model assessment of insulin resistance (HOMA) were significantly lower in the Ala12Ala group than in the Pro12Pro group after the mixed meal. In contrast, the groups did not differ in insulin levels and HOMA after the OGTT. To investigate if differences between a fat-containing meal and OGTT are caused by adiponectin, we examined a BMI- and age-matched subgroup. No differences were found between the genotypic groups. The effects of the PPARγ2 polymorphism on insulin sensitivity are mediated by affluent dietary fat. We did not find evidence that adiponectin as a fatty-acid-dependent adipocyte factor is a causative factor for this phenomenon.
Effects of avermectin residues in cattle dung on yellow dung flyScathophaga stercoraria(Diptera: Scathophagidae) populations in grazed pastures
Authors: Webb L. , Beaumont D.J. , Nager R.G. , McCracken D.I.
Published: April 2007

The effects of avermectin exposure on natural populations of the yellow dung fly,Scathophaga stercorariaLinnaeus, were investigated at the field scale on farms in south-west Scotland. Pastures forming the focus of the study were grazed with either untreated cattle or cattle receiving standard, manufacturer-recommended treatment regimes of an avermectin product. Flies were sampled between April and July in 2002 and 2003 using dung-baited pitfall traps. Abundance and wing asymmetry inS. stercorariapopulations were examined in relation to a range of environmental and management variables (including avermectin exposure, pasture management intensity, weather and season). Data used for abundance analyses were collected in fields where treated cattle had been dosed with either doramectin or ivermectin, while the data for the asymmetry analyses were from a subset of fields where treated cattle had been dosed with doramectin only. While abundance ofS. stercorariavaried significantly between years and with season, there was no difference in their abundance between fields grazed by avermectin-treated or untreated cattle. Asymmetry was significantly higher in fly populations in fields grazed by doramectin-treated cattle, suggesting that exposure to doramectin during development could have imposed some degree of environmental stress. While these results suggest that exposure to doramectin residues in dung on grazed pastures may have sublethal effects on the insects developing in that dung, there was no evident avermectin effect on the abundance of adultS. stercorariaoccurring in the pastures.
Influence of temperature, photoperiod and humidity on oviposition and egg hatch of the root-feeding flea beetleLongitarsus bethae(Chrysomelidae: Alticinae), a natural enemy of the weedLantana camara(Verbenaceae)
Authors: Simelane D.O.
Published: April 2007

The root-feeding flea beetleLongitarsus bethaeSavini & Escalona, was introduced into South Africa as a candidate biological control agent for the noxious and invasive weed,Lantana camaraL. As part of the study to predict the beetles' survival in its new range, the influence of climatic conditions on its egg development and reproductive performance were investigated in the laboratory. The threshold temperature (T°) and degree-days (DD) required for egg hatch were determined after exposing the eggs to various constant temperatures (12, 17, 22, 27 and 32°C) in separate growth chambers. The DD required for egg hatch was 178.6, and the temperature threshold required for egg hatch was 11.3°C. Survival of eggs varied from 27 to 56% at 32 and 17°C, respectively, and was optimum between 17 and 25°C. Oviposition was examined under high and low relative humidity (RH) regimes while egg hatch was determined at six RH levels, each maintained in a separate controlled growth chamber set at a constant temperature (25°C). Whilst RH had no influence on oviposition, eggs were highly susceptible to aridity, and continuous exposure to relative humidity below 63% for more than three days was wholly lethal at 25°C. Optimum egg hatch occurred at RH between 85 and 95% for up to 12 days. The effect of day length on oviposition and subsequent egg hatch was investigated under two photoperiod regimes. Neither oviposition nor subsequent egg hatch was influenced by photoperiod. The knowledge obtained will be useful for mass rearing as well as field release programmes forL. bethae.
Water stress augments silicon-mediated resistance of susceptible sugarcane cultivars to the stalk borer Eldana saccharina (Lepidoptera: Pyralidae)
Authors: Kvedaras O.L. , Keeping M.G. , Goebel F.-R. , Byrne M.J.
Published: April 2007

Silicon (Si) can improve resistance of plants to insect attack and may also enhance tolerance of water stress. This study tested if Si-mediated host plant resistance to insect attack was augmented by water stress. Four sugarcane cultivars, two resistant (N21, N33) and two susceptible (N26, N11) to Eldana saccharina Walker were grown in a pot trial in Si-deficient river sand, with (Si+) and without (Si−) calcium silicate. To induce water stress, irrigation to half the trial was reduced after 8.5 months. The trial was artificially infested with E. saccharina eggs after water reduction and harvested 66 days later. Silicon treated, stressed and non-stressed plants of the same cultivar did not differ appreciably in Si content. Decreases in numbers of borers recovered and stalk damage were not associated with comparable increases in rind hardness in Si+ cane, particularly in water-stressed susceptible cultivars. Overall, Si+ plants displayed increased resistance to E. saccharina attack compared with Si− plants. Borer recoveries were significantly lower in stressed Si+ cane compared with either stressed Si− or non-stressed Si− and Si+ cane. Generally, fewer borers were recovered from resistant cultivars than susceptible cultivars. Stalk damage was significantly lower in Si+ cane than in Si− cane, for N21, N11 and N26. Stalk damage was significantly less in Si+ combined susceptible cultivars than in Si− combined susceptible cultivars under non-stressed and especially stressed conditions. In general, the reduction in borer numbers and stalk damage in Si+ plants was greater for water-stressed cane than non-stressed cane, particularly for susceptible sugarcane cultivars. The hypothesis that Si affords greater protection against E. saccharina borer attack in water-stressed sugarcane than in non-stressed cane and that this benefit is greatly enhanced in susceptible cultivars is supported. A possible active role for soluble Si in defence against E. saccharina is proposed.