bluuebunny/crossref_metadata_2025 huggingface dataset:
BALLISTIC ELECTRON ACCELERATION NEGATIVE-DIFFERENTIAL-CONDUCTIVITY DEVICES
Authors: Eastman Lester F. , Schaff William J. , Cha Ho-Young , Chen Xiao-Dong , Spencer Michael G. , Ridley Brian K.
Published: September 2006

A short drift distance N - I - N device, with high electric field, allows ballistic electron accelerations and drift. Conditions can be enhanced by using a heterojunction to launch electrons at finite energy. Initial I(V) results without the heterojunctions are presented, as well as the design of a structure which has the heterostructure, projected results are speculated upon, along with an on-chip circuit being used.
RECENT PROGRESS ON GaN-BASED ELECTRON DEVICES
Authors: Uemoto Yasuhiro , Hirose Yutaka , Murata Tomohiro , Ishida Hidetoshi , Hikita Masahiro , Yanagihara Manabu , Inoue Kaoru , Tanaka Tsuyoshi , Ueda Daisuke , Egawa Takashi
Published: September 2006

We present results of some novel AlGaN/GaN heterojunction field-effect transistors (HFETs) specifically developed for RF front-end and power applications. To reduce the parasitic resistance, two unique techniques: selective Si doping into contact area and a superlattice (SL) cap structure, are developed. With the selective Si doping method, a transistor with an on-state resistance as low as 1.86 Ω·mm and a Tx/Rx switch IC with very low insertion loss (0.26 dB) and very high power handling capability (P1dB over 40 dBm) were obtained. With the SL cap HFETs, an ultra low source resistance of 0.4 Ω·mm was achieved and excellent DC and RF performances were demonstrated. The typical characteristics of these HFETs are: maximum transconductance of over 400 mS/mm, maximum drain current of 1.2 A/mm, cut-off frequency of 60 GHz, maximum oscillation frequency of 140 GHz, and a very low noise figure of 0.7 dB with 15 dB gain at 12 GHz. For power applications, in order to significantly reduce fabrication cost, we fabricated the AlGaN/GaN HFET on a conductive Si substrate with a source-via grounding (SVG) structure. The device has a very low on-state sheet resistance of 1.9 mΩ·cm2, a high off-state breakdown voltage of 350 V, and a current handling capability of 150 A. In addition, a sub-nano second switching response with t r of 98 ps and t f of 96 ps with a current density as high as 2.0 kA/cm2 is demonstrated for the first time.
A QUANTUM DOT MICROCAVITY TERAHERTZ LASER
Authors: Solomon G. S. , Xie Z. G. , Agrawal M.
Published: September 2006

We discuss a THz laser device based on a semiconductor quantum dot (QD) gain medium, where the lasing occurs through discrete conduction states. An ensemble of QDs is selectively placed in a high quality cavity, called a microdisk, which is resonant with a terahertz intersublevel QD transition. We simulate the rate equations governing lasing and discuss a variety of processes affecting lasing including nonradiative recombination and the ground state decay rate.
FEASIBILITY OF AN OPTICAL FREQUENCY MODULATION SYSTEM FOR FREE-SPACE OPTICAL COMMUNICATIONS
Authors: LURYI SERGE , GOUZMAN MIKHAIL
Published: September 2006

We consider a free-space communication system based on optical frequency modulation (FM), where the information is encoded by a time-variable wavelength. As is well known, broadband FM systems use a transmission bandwidth that is larger than the signal's information bandwidth, thus enabling an enhancement of the signal-to-noise ratio (SNR) and hence the effective information rate per unit transmitter power. Because of the atmospheric conditions, any optical free-space communication system, contemplated at a terrestrial level, must operate at mid-infrared wavelengths in the range λ = 2.5 2.8 μ m . Development of rapidly tunable single-frequency lasers in this wavelength range is quite feasible, based on the current experience with tunable telecom lasers at 1.5 μm. Nevertheless, there is no currently available optical FM system. The main difficulty is associated not so much with the tunable optical sources, as with the implementation of a wavelength-discriminating receiver system that would take advantage of the enhanced SNR. In our view, the key enabling solution is optical superheterodyne with a local oscillator implemented as a tunable mid-infrared laser similar to that at the source. The intermediate frequency can be tuned to lie either in a frequency range directly accessible to electronic limiting amplifier and frequency discriminator or, in a multichannel system, to a second heterodyne in the terahertz range.
BIOLOGICALLY-INSPIRED CHEMICALLY-DIRECTED SELF-ASSEMBLY OF SEMICONDUCTOR QUANTUM-DOT-BASED SYSTEMS: PHONON-HOLE SCATTERING IN DNA BOUND TO DNA-QUANTUM-DOT COMPLEXES
Authors: STROSCIO MICHAEL A. , DUTTA MITRA
Published: September 2006

This paper focuses on: (a) the concept and use of chemically-directed assembly to integrate nanoscale quantum dots at densities above 1017 cm-3 with biomolecular interconnecting structures; and (b) the phenomena of phonon absorption and emission from holes propagating in DNA molecules that are bond on one terminus to semiconductor quantum dots.
MIXED-VALENCE TRANSITION METAL COMPLEX BASED INTEGRAL ARCHITECTURE FOR MOLECULAR COMPUTING (I): ATTACHMENT OF LINKER MOLECULE TO SILICON (100) - 2×1 SURFACE
Authors: ZHAO PEIJI , WOOLARD DWIGHT , SEMINARIO JORGE M. , TREW ROBERT
Published: September 2006

Based on density functional theory, we have calculated and analyzed the electrical characteristics of silicon (100) - 2×1 surfaces. The calculation results show that the sulfur atom establishes a Schottky-like contact when it is used to tethering the surface and the molecule. In contrast to the Si – S linkage, a direct Si – C linkage does not build up a barrier between the molecule and the surface of silicon. This type of contact is a Ohmic-like contact. The origin of the characteristics of the contacts is analyzed. A basic rule for designing the electrical characteristics of the molecule - surface of silicon is presented.
SILICON FIBRE TECHNOLOGY DEVELOPMENT FOR WEARABLE AND AMBIENT ELECTRONICS APPLICATIONS
Authors: HEALY THOMAS , DONNELLY JULIE , O'NEILL BRENDAN , ALDERMAN JOHN , MATHEWSON ALAN
Published: September 2006

The concept of silicon fibre technology follows the aspiration of making whole computers recede into textile format, which can be used in a wearable or ambient environment. The integration of IC technology into fibre format is an important development for a wide range of emerging scientific applications from wearable vital sign health monitoring systems [1] to Ambient Intelligence Microsystems.

This concept is achieved by building a device in silicon on insulator (SOI) [2] material and under-cutting the sacrificial SiO 2 layer by a combination of isotropic and anisotropic etch processes, to leave a freestanding functional fibre. A demonstration of functionality based on this technology was produced in the form of a PN diode on a fibre [3]. After demonstrating the feasibility of the concept, subsequent active device circuits were designed and fabricated as a more complex demonstration of functionality.

One of the primary considerations involved with this technology is the interconnection of these flexible silicon structures to each other and to the outside environment. A novel interconnection protocol has been developed and a prototype demonstration of a flexible LED circuit has been fabricated.
SILICON-BASED INTEGRATED MOSFETS AND MESFETS: A NEW PARADIGM FOR LOW POWER, MIXED SIGNAL, MONOLITHIC SYSTEMS USING COMMERCIALLY AVAILABLE SOI
Authors: YANG JINMAN , BALIJEPALLI ASHA , THORNTON TREVOR J. , VANDERSAND JAMES , BLALOCK BENJAMIN J. , WOOD MICHAEL E. , MOJARRADI MOHAMMAD M.
Published: September 2006

Metal Semiconductor Field Effect Transistors fabricated using compound semiconductor materials have important applications in high-speed/low-noise communication systems. However, their integration densities are low compared to silicon technologies, and it is difficult to combine them with conventional CMOS for single-chip, mixed-signal circuit applications. In this paper we describe how silicon-on-insulator MESFETs can be fabricated alongside conventional MOSFETs using a commercially available silicon-on-insulator foundry. The process flow for the integrated MOSFETS and MESFETs is presented. Measurements from MESFETs fabricated using a commercial foundry demonstrate good depletion-mode device operation. The measured data confirms a square-law behavior for the saturated drain current, which can be reproduced using readily available MESFET models for Spice circuit simulation. The Spice model is applied to a simple differential-pair amplifier and the modeled results compared to measured data.
Biodiversity Informatics
Authors: Johnson Norman F.
Published: September 2006

Biodiversity informatics is an emerging field that applies information management tools to the management and analysis of species-occurrence, taxonomic character, and image data. A wide and growing range of tools is available for both curators and researchers. The development and implementation of formal data exchange standards and query protocols have made it possible to integrate data holdings from collections around the world. The current technological environment is summarized; protocols, standards, and tools for data management, sharing, and integration are reviewed; and methods and tools for analyzing species-occurrence and character data are examined. Direct access to primary data and imagery has the power to transform the means by which taxonomy is practiced and its results disseminated to the general community.
GLP-2 rapidly activates divergent intracellular signaling pathways involved in intestinal cell survival and proliferation in neonatal piglets
Authors: Burrin Douglas G. , Stoll Barbara , Guan Xinfu , Cui Liwei , Chang Xiaoyan , Hadsell Darryl
Published: September 2006

We previously demonstrated the dose-dependent glucagon-like peptide (GLP)-2 activation of intracellular signals associated with increased epithelial cell survival and proliferation in the neonatal intestine. Our current aim was to quantify the acute, temporal GLP-2 activation of these key intracellular signals and relate this to changes in epithelial cell survival and proliferation in the neonatal intestine. We studied 29 total parenteral nutrition-fed neonatal piglets infused intravenously with either saline (control) or human GLP-2 (420 μmol·kg−1·h−1) for 1, 4, or 48 h. GLP-2 infusion increased small intestinal weight, DNA and protein content, and villus height at 48 h, but not at 1 or 4 h. Intestinal crypt and villus apoptosis decreased and crypt cell proliferation and protein synthesis increased linearly with duration of GLP-2 infusion, but were statistically different from controls only after 48 h. Before the morphological and cellular kinetic changes, GLP-2 rapidly activated putative GLP-2 receptor downstream signals within 1–4 h, including phosphorylation of protein kinase A, protein kinase B, extracellular signal-regulated kinase 1/2, and the transcription factors cAMP response element-binding protein and c-Fos. GLP-2 rapidly suppressed caspase-3 activation and upregulated Bcl-2 abundance within 1 h, whereas there was an increase in apoptosis inhibitors X-linked inhibitor of apoptosis at 1 h and cellular inhibitor of apoptosis-2 at 4 and 48 h. We also show that the increased c-Fos and reduced active caspase-3 immunostaining after GLP-2 infusion was localized in epithelial cells. We conclude that GLP-2-induced activation of intracellular signals involved in both cell survival and proliferation occurs rapidly and precedes the trophic cellular kinetic effects that occur later in intestinal epithelial cells.
Expression of mitochondrial biogenesis-signaling factors in brown adipocytes is influenced specifically by 17β-estradiol, testosterone, and progesterone
Authors: Rodríguez-Cuenca S. , Monjo M. , Gianotti M. , Proenza A. M. , Roca P.
Published: September 2006

Control of mitochondrial biogenesis in brown adipose tissue (BAT), as part of the thermogenesis program, is a complex process that requires the integration of multiple transcription factors to orchestrate mitochondrial and nuclear gene expression. Despite the knowledge of the role of sex hormones on BAT physiology, little is known about the effect of these hormones on the mitochondrial biogenic program. The aim of this study was to determine the effect of testosterone, 17β-estradiol, and progesterone on the expression of nuclear factors involved in the control of mitochondrial biogenesis and thermogenic function such as pparγ, pgc1α, nrf1, gabpa, and tfam, and also an inhibitor of PI3K-Akt pathway, recently found to be involved in the control of mitochondrial recruitment ( pten). For this purpose, an in vitro assay using cell-cultured brown adipocytes was used to address the role of steroid hormones, progesterone, testosterone, and 17β-estradiol on the mRNA expression of these factors by real-time PCR. Thus 17β-estradiol seemed to exert a dual effect, activating the PI3K-Akt pathway by inhibiting pten mRNA expression and also inhibiting nrf1 and tfam mRNA expression. Progesterone seemed to positively stimulate mitochondriogenesis and BAT differentiation by increasing the mRNA expression of the gabpa-tfam axis and pparγ, respectively, but also exerted a negative output by increasing pten mRNA levels. Finally, testosterone inhibited the transcription of pgc1α, the master factor involved in UCP1 expression and mitochondrial biogenesis. In conclusion, our results support the idea that sex hormones have direct effects on different mediators of the mitochondriogenesis program.
Adipose tissue in offspring ofLeprdb/+mice: early-life environment vs. genotype
Authors: Lambin Suzan , van Bree Rita , Caluwaerts Silvia , Vercruysse Lisbeth , Vergote Ignace , Verhaeghe Johan
Published: September 2006

Gravidas with obesity and diabetes (“diabesity”) may transmit this syndrome to their children through genetic and nongenetic mechanisms. Here, we used the Leprdb/+diabese mouse to examine the magnitude of these transmission modes, focusing on adipose tissue (AT). We compared the following six groups: wild-type (+/+) offspring from +/+ or db/+ dams (different early life environment) and db/+ offspring from db/+ dams, fed a standard or high-fat diet. Weight gain (0–8 wk) was higher in +/+ offspring from db/+ vs. +/+ mothers, and even higher in db/+ vs. +/+ offspring from db/+ mothers. In addition, we observed a stepwise increase in AT and adipocyte size in +/+ from +/+ mice, +/+ from db/+ mice, and db/+ mice at 8 wk. Differences in weight and adiposity between +/+ offspring from db/+ vs. +/+ dams were more pronounced in males than in females. Leptin and apelin mRNA levels in white and brown AT were higher in +/+ offspring from db/+ vs. +/+ dams; however, leptin, apelin, and tumor necrosis factor-α expression were boosted more robustly in db/+ offspring. The high-fat diet amplified AT differences between db/+ vs. +/+ offspring from db/+ dams, but not between +/+ offspring from db/+ vs. +/+ dams. Moreover, db/+ but not +/+ offspring from db/+ mothers were insulin-resistant and hyperinsulinemic after a glucose challenge. In conclusion, the genetic transmission of the diabesity phenotype clearly prevailed, but the early-life diabesity environment had discernible effects on postnatal weight gain as well as on adipocyte size and adipokine expression at a postpubertal age.
Quantification of amino acid transport through interstitial fluid: assessment of four-compartment modeling for muscle protein kinetics
Authors: Gore Dennis C. , Wolfe Robert R. , Chinkes David L.
Published: September 2006

The purpose of this study was to assess a novel technique for quantifying in vivo muscle protein metabolism and phenylalanine transport in septic patients and normal volunteers and thereby assess the influence of sepsis on muscle protein kinetics. In patients resuscitated from sepsis, blood flow and edema may influence the extent of muscle loss. Six adult patients septic from pneumonia underwent a study protocol consisting of infusion of isotopic phenylalanine, indocyanine green dye, and sodium bromide; biopsies of skeletal muscle; and sampling from the femoral artery, vein, and interstitial fluid. Study results demonstrate a substantial net catabolism of muscle, an accelerated flux of phenylalanine, and an increased leg blood flow for septic patients compared with normal volunteers. For septic patients and normal volunteers, the rate of phenylalanine transport through the interstitium was rate limiting for the movement of phenylalanine between vasculature and muscle. Measurements demonstrate a concentration gradient of phenylalanine favoring the net efflux of amino acids from the leg in the septic patients. Despite whole body edema, the extracellular fluid volume within muscle of septic patients was similar to normal. These findings demonstrate that the extent of muscle loss in critically ill patients results from the net increase in the rate of muscle protein breakdown, which subsequently drives amino acids through the interstitial compartment down their concentration gradient. Therefore, any effective therapy to correct illness-induced muscle catabolism should be directed at altering the rates of breakdown and synthesis of muscle protein and are not likely related to tissue edema.
Monoaminergic Control of Cauda-Equina-Evoked Locomotion in the Neonatal Mouse Spinal Cord
Authors: Gordon Ian T. , Whelan Patrick J.
Published: September 2006

Monoaminergic projections are among the first supraspinal inputs to innervate spinal networks. Little is known regarding the role of monoamines in modulating ongoing locomotor patterns evoked by endogenous release of neurotransmitter. Here we activate a locomotor-like rhythm by electrical stimulation of afferents and then test the modulatory effects of monoamines on the frequency, pattern, and quality of the rhythm. Stimulation of the cauda equina induced a rhythm consisting of left-right and ipsilateral alternation indicative of locomotor-like activity. First, we examined the effects of noradrenaline (NA), serotonin (5-HT), or dopamine (DA) at dose levels that did not elicit locomotor activity. Bath application of NA and DA resulted in a depression of the cauda-equina-evoked rhythm. Conversely, bath-applied 5-HT increased both the amplitude and cycle period of the evoked rhythm, an effect that was mimicked by the addition of 5-HT2 agonists to the bath. Application of 5-HT7 agonists disrupted the evoked rhythmic behavior. Next, we examined the effects of NA α1 and α2 agonists and found that the suppressive effects of NA on the rhythm could be reproduced by adding the α2 agonist, clonidine, to the bath. In contrast, bath applying the α1 agonist, phenylephrine, increased the amplitude and duration of the cycle period. Finally, the suppressive effects of DA were not replicated by the administration of D1, D2, or D3 agonists although application of NA α2 antagonists reversed the effects of DA. Application of D1 agonists, increased the amplitude of the bursts but did not affect the cycle period. Our results indicate that monoamines can control the expression, pattern, and timing of cauda-equina-evoked locomotor patterns in developing mice.
Intracortical Circuits in Rat Anterior Cingulate Cortex Are Activated by Nociceptive Inputs Mediated by Medial Thalamus
Authors: Yang Jenq-Wei , Shih Hsi-Chien , Shyu Bai-Chuang
Published: September 2006

We investigated the afferents and intracortical synaptic organization of the anterior cingulate cortex (ACC) during noxious electrical stimulation. Extracellular field potentials were recorded simultaneously from 16 electrodes spanning all layers of the ACC in male Sprague–Dawley rats anesthetized by halothane inhalation. Laminar-specific transmembrane currents were calculated with the current source density analysis method. Two major groups of evoked sink currents were identified: an early group (latency = 54.04 ± 2.12 ms; 0.63 ± 0.07 mV/mm2) in layers V–VI and a more intense late group (latency = 80.07 ± 4.85 ms; 2.16 ± 0.22 mV/mm2) in layer II/III and layer V. Multiunit activities were evoked mainly in layer V and deep layer II/III with latencies similar to that of the early and late sink groups. The evoked EPSP latencies of pyramidal neurons in layers II/III and V related closely with the sink currents. The sink currents were inhibited by intracortical injection of CNQX (1 mM, 1 μl), a glutaminergic receptor antagonist, and enhanced by intraperitoneal (5 mg/kg) and intracortical (10 μg/μl, 1 μl) injection of morphine, a μ-opioid receptor agonist. Paired-pulse depression was observed with interpulse intervals of 50 to 1,000 ms. High-frequency stimulation (100 Hz, 11 pulses) enhanced evoked responses in the ACC and evoked medial thalamic (MT) unit activities. MT lesions blocked evoked responses in the ACC. Our results demonstrated that two distinct synaptic circuits in the ACC were activated by noxious stimuli and that the MT is the major thalamic relay that transmits nociceptive information to the ACC.
Multiple mechanisms limit the duration of wakefulness in Drosophila brain
Authors: Zimmerman John E. , Rizzo Wendy , Shockley Keith R. , Raizen David M. , Naidoo Nirinjini , Mackiewicz Miroslaw , Churchill Gary A. , Pack Allan I.
Published: September 2006

The functions of sleep and what controls it remain unanswered biological questions. According to the two-process model, a circadian process and a homeostatic process interact to regulate sleep. While progress has been made in understanding the molecular and cellular functions of the circadian process, the mechanisms of the homeostatic process remain undiscovered. We use the recently established sleep model system organism Drosophila melanogaster to examine dynamic changes in gene expression during sleep and during prolonged wakefulness in the brain. Our experimental design controls for circadian processes by killing animals at three matched time points from the beginning of the consolidated rest period [Zeitgeber time (ZT) 14)] under two conditions, sleep deprived and spontaneously sleeping. Using ANOVA at a false discovery rate of 5%, we have identified 252 genes that were differentially expressed between sleep-deprived and control groups in the Drosophila brain. Using linear trends analysis, we have separated the significant differentially expressed genes into nine temporal expression patterns relative to a common anchor point (ZT 14). The most common expression pattern is a decrease during extended wakefulness but no change during spontaneous sleep ( n = 114). Genes in this category were involved in protein production ( n = 47), calcium homeostasis, and membrane excitability ( n = 5). Multiple mechanisms, therefore, act to limit wakefulness. In addition, by studying the effects of the mechanical stimulus used in our deprivation studies during the period when the animals are predominantly active, we provide evidence for a previously unappreciated role for the Drosophila immune system in the brain response to stress.
Urine from Scrapie-Infected Hamsters Comprises Low Levels of Prion Infectivity
Authors: Kariv-Inbal Zehavit , Ben-Hur Tamir , Grigoriadis Nikolaos C. , Engelstein Roni , Gabizon Ruth
Published: September 2006

The question of whether prion diseases can be transmitted by body fluids has important epidemiological, environmental and economical implications. In this work, we set to investigate whether urine collected from scrapie-infected hamsters can transmit fatal or subclinical infectivity to normal hamsters. After prolonged incubation times ranging from 300 to 700 days, a small number of animals inoculated with scrapie urine succumbed to scrapie disease, and several asymptomatic hamsters presented low levels of PrPSc in their brains. In addition, most of the asymptomatic hamsters inoculated with scrapie urine, as opposed to those inoculated with normal urine, presented extensive gliosis as well as protease-resistant light chain IgG in their urine, a molecule shown by us and others to be a surrogate marker for prion infection. Our results suggest that urine from scrapie-infected hamsters can transmit a widespread subclinical disease that in some cases develops into fatal scrapie.
Genetic Variability in CHMP2B and Frontotemporal Dementia
Authors: Momeni Parastoo , Rogaeva Ekaterina , van Deerlin Vivianna , Yuan Wuxing , Grafman Jordan , Tierney Michael , Huey Edward , Bell Jason , Morris Chris M. , Kalaria Rajesh N. , van Rensburg Susan J. , Niehaus Dana , Potocnik Felix , Kawarai Toshitaka , Salehi-Rad Shabnam , Sato Christine , St. George-Hyslop Peter , Hardy John
Published: September 2006

A nonsense/protein chain-terminating mutation in the CHMP2B gene has recently been reported as a cause of frontotemporal dementia (FTD) in the single large family known to show linkage to chromosome 3. Screening for mutations in this gene in a large series of FTD families and individual patients led to the identification of a protein-truncating mutation in 2 unaffected members of an Afrikaner family with FTD, but not in their affected relatives. The putative pathogenicity of CHMP2B mutations for dementia is discussed.
Gene Therapy of Uterine Leiomyoma: Adenovirus-Mediated Herpes Simplex Virus Thymidine Kinase/Ganciclovir Treatment Inhibits Growth of Human and Rat Leiomyoma Cells in vitro and in a Nude Mouse Model
Authors: Salama S.A. , Kamel M. , Christman G. , Wang H.Q. , Fouad H.M. , Al-Hendy A.
Published: September 2006

Uterine leiomyomas (LM) affect a high percentage of reproductive-age women. They develop as discrete, well-defined tumors that are easily accessible with imaging techniques – making this disease ideal for localized gene therapy approaches. In this study, we determined the efficacy of adenovirus-mediated herpes simplex virus thymidine kinase gene transfer in combination with ganciclovir (Ad-TK/GCV) as a potential therapy for LM. Rat ELT-3 LM cells and human LM cells were transfected with different multiplicity of infections (10–100 plaque forming units [PFU]/cell) of Ad-TK and treated with GCV (5, 10, or 20 µg/ml) for 5 days. To test the bystander effect, Ad-TK-transfected ELT-3 cells (100 PFU/cell) or LM cells (10 PFU/cell) were cocultured with corresponding nontransfected cells at increasing percentages and treated with GCV followed by cell counting. In ELT-3 cells transfected with Ad-TK/GCV (10, 20, 50, or 100 PFU/cell), the cell count was reduced by 24, 42, 77, and 87%, respectively, compared with the control cells (transfected with Ad-Lac Z/GCV). Similarly, in LM cells transfected with Ad-TK/GCV (10, 50, or 100 PFU/cell), the cell count was reduced by 31, 62, and 82%, respectively, compared with the control. A strong bystander effect was noted in both ELT-3 and LM cells with significant killing (p = 0.001) at a ratio of infected:uninfected cells of only 1:99 and maximal killing at 1:4. This study demonstrates the potential efficacy of the Ad-TK/GCV gene therapy approach as a viable nonsurgical alternative treatment for uterine LM.
Association of Elevated Levels of Vascular Endothelial Growth Factor in Obstructive Sleep Apnea Syndrome with Patient Age rather than with Obstructive Sleep Apnea Syndrome Severity
Authors: Peled Nir , Shitrit David , Bendayan Daniele , Peled Eli , Kramer Mordechai R.
Published: September 2006

Background: Although certain studies report high levels of vascular endothelial growth factor (VEGF) in obstructive sleep apnea syndrome (OSAS), the effect of systemic hypoxia on circulating VEGF remains controversial. Objectives: To study the association of serum VEGF and OSAS in a large group of patients. Methods: One hundred patients with OSAS (mean age 58.1 ± 12.4 years, mean body mass index 30.6 ± 5.4 kg/m2) were tested for serum VEGF levels, and the findings were correlated with the severity of OSAS, as determined by the apnea-hypopnea index (AHI) on the basis of polysomnography and background data. Results: The mean AHI was 40.0 ± 21.2 (range 10–106). Mean minimal oxygen saturation was 80.6 ± 11.7% (range 43–98%) and mean time of oxygen saturation under 90% was 50.0 ± 75.0 min (range 0–300 min). The mean VEGF level was 445.2 ± 289.8 pg/ml in the study group (vs. 280 pg/ml reported in normal controls). The mean platelet count was 233.8 ± 64.4 103/ml and the mean VEGF/platelet ratio was 1.95 ± 1.40 pg/106. There was no association of VEGF or VEGF/platelets with the severity of OSAS. However, both factors showed a significant correlation with patient age (r = 0.224, p = 0.01 and r = 0.425, p = 0.01, respectively). Age was the only parameter to significantly predict VEGF and VEGF/platelets on multivariate analysis (R2 = 0.713, p = 0.001 and R2 = 0.844, p = 0.001, respectively). Conclusion: The elevation of serum VEGF in OSAS is not associated with the severity of the disease, but it is associated with patient age. VEGF might be involved in the long-term adaptive mechanism in OSAS, and its age-dependent increase might partly explain the reduced mortality in elderly OSAS patients.
Roflumilast, a Phosphodiesterase 4 Inhibitor, Reduces Airway Hyperresponsiveness after Allergen Challenge
Authors: Louw C. , Williams Z. , Venter L. , Leichtl S. , Schmid-Wirlitsch C. , Bredenbröker D. , Bardin P.G.
Published: September 2006

Background: Roflumilast, an oral, once-daily phosphodiesterase 4 inhibitor, is currently in clinical development for the treatment of asthma. Objectives: This pilot study examined the effect of roflumilast on allergen-induced airway hyperresponsiveness (AHR) to histamine challenge and asthmatic response to allergen challenge. Methods: In a randomized, double-blind, 2-period, crossover trial, 13 patients with mild allergic asthma [mean forced expiratory volume in 1 s (FEV1) % predicted = 86%] received a single dose of oral roflumilast 1,000 µg or placebo. Patients were administered roflumilast 60 min before allergen challenge, and asthmatic responses were assessed via change in FEV1 ≤9 h after allergen challenge. AHR to histamine provocation was measured before and repeated 24 h after allergen provocation. Patients inhaled histamine in doubling concentrations until attaining a decrease in FEV1 of ≤20% (PC20FEV1). Results: Roflumilast had no detectable bronchodilator activity 60 min after administration. Roflumilast significantly attenuated AHR compared with placebo, with a mean change in pre- to postallergen challenge PC20FEV1 ratio of 1.23 ± 2.75 and 2.51 ± 2.95 for roflumilast and placebo, respectively (p = 0.002). During the late asthmatic response, roflumilast reduced the mean maximum decrease in FEV1 from 2 to 9 h after allergen challenge compared with placebo (p = 0.005). Additionally, FEV1 at 9 h after challenge was significantly higher in patients treated with roflumilast (p = 0.03). Early asthmatic responses to allergen challenge were not significantly reduced by the single dose of roflumilast. Conclusions: Roflumilast attenuated allergen-induced AHR in patients with mild asthma. These results support further investigation of roflumilast as an anti-inflammatory treatment of asthma.
Toward the micro and macro-level consequences of interactional justice in cross-cultural joint ventures
Authors: Lu Yadong
Published: September 2006

Nested within the logic of social exchange, this study addresses the micro and macro-level consequences of interactional justice between boundary-spanning executives in cross-cultural joint ventures. At the micro-level, this study examines how interactional justice affects these executives' decision-making effectiveness and the interpersonal trust between boundary-spanning officers. At the macro-level, the study analyzes how interactional justice affects the levels of conflict and attachment between partner organizations from different nations. This study further analyzes how interactional justice buffers the effects of national cultural differences between partner organizations on the above consequences. Analysis of 152 international joint ventures suggests that interactional justice is positively associated with decision effectiveness, interpersonal trust, and interorganizational attachment, and that interactional justice suppresses the negative influence of national cultural differences between partners on interorganizational attachment.
The glass partition: Obstacles to cross-sex friendships at work
Authors: Elsesser Kim , Peplau Letitia Anne
Published: September 2006

This study explores cross-sex friendships within the professional workplace and examined the impact of the workplace environment and heightened awareness of sexual harassment on cross-sex friendship formation. Results from interviews with 41 professionals suggest the existence of obstacles to developing cross-sex friendships at work. Specifically, these professionals worried that their cross-sex friends would misinterpret their friendliness as romantic or sexual interest, that their co-workers would misinterpret their friendliness to a cross-sex friend, and that their humor and conversational topics might be perceived by a cross-sex friend as sexual harassment. Barriers to cross-sex friendship at work were labeled the ‘glass partition,’ and the potential impact of this glass partition on women's and men's careers is discussed.
Owners or traders? Conceptualizations of institutional investors and their relationship with corporate managers
Authors: Hendry John , Sanderson Paul , Barker Richard , Roberts John
Published: September 2006

We draw on a series of in-depth interviews with senior managers from institutional investors and large listed corporations to explore how different conceptualizations of institutional investors, their role in the corporate governance process, and their interactions with corporate management, are reflected in the accounts of the actors concerned. We find that the conceptualizations in terms of ownership and agency that dominate both academic and popular discourses are marginal to the actors’ accounts. Rather, both fund managers and company managers conceptualize institutional investors primarily as financial traders who happen,as a result of their trading, to control key resources, but whose interests are effectively divorced from those of long-term share owners. Our analysis suggests that far from being mitigated by the large share blocks of institutional investors, as some commentators have suggested, the separation of ownership from control has been compounded in the UK by a separation of accountability from responsibility, with the interests of the institutions holding managers accountable being quite different from those of the owner-beneficiaries to whom they feel responsible. This raises significant challenges for corporate governance policy as well as new issues for research into the governance process.
Preparation of PMP Foam Doped with Copper Nanopowders
Authors: Du Kai , Zhang Lin , Luo Xuan , Wang Chao-Yang , Yin Qiang
Published: September 2006

Nanometer copper (Cu)-doped poly-4-methyl-1-pentene (PMP) foam is prepared by thermally induced phase inversion and ultrasonic dispersal. The nanometer Cu powders are dispersed uniformly in the horizontal direction of the foam and sink a bit in the vertical direction. The practical concentration of Cu atoms in the foams is lower than the theoretical concentration. Experiments reveal that a higher concentration of Cu atoms results in a finer foam structure.
Measurement of the Nonuniform Thermal Expansion Coefficient of a PVC Foam Core by Speckle Interferometry - Influence on the Mechanical Behavior of Sandwich Structures
Authors: Ferreira Carlos , Jacquemin FrédéRic , Casari Pascal
Published: September 2006

This article aims to investigate the mechanical behavior of a PVC foam core under thermal loading. The speckle, full-field interferometric technique is used for the determination of the nonlinear coefficient of thermal expansion of PVC foam. A significant gradient is highlighted and correlated to a gradient in density or hardness observed experimentally. Finally, a simulation shows the effect of taking such gradients into account for the stress state calculation for a sandwich structure submitted to a temperature variation.
Effects of CO2 and Talc Contents on Foaming Behavior of Recyclable High-melt-strength PP
Authors: Kaewmesri Wanrudee , Lee Patrick C. , Park Chul B. , Pumchusak Jantrawan
Published: September 2006

This article presents an experimental study on the foaming behavior of recyclable high-melt-strength (HMS) branched polypropylene (PP) with CO2as a blowing agent. The foamability of branched HMS PP has been evaluated using a tandem foaming extruder system. The effects of CO2and nucleating agent contents on the final foam characteristics have been thoroughly investigated. Low density (i.e., 12-14-fold), fine-celled (i.e., 107-109cells/cm3) PP foams were successfully produced using a small amount of talc (i.e., 0.8 wt%) and 5 wt% CO2.
The Role of Rivalry
Authors: Apesteguia Jose , Maier-Rigaud Frank P.
Published: September 2006

Despite a large theoretical and empirical literature on public goods and common-pool resources, a systematic comparison of these two types of social dilemmas is lacking. In fact, there is some confusion about these two types of dilemma situations. As a result, they are often treated alike. In line with the theoretical literature, the authors argue that the degree of rivalry is the fundamental difference between the two games. Furthermore, they experimentally study behavior in a quadratic public good and a quadratic common-pool resource game with identical Pareto-optimum but divergent interior Nash equilibria. The results show that participants clearly perceive the differences in rivalry. Aggregate behavior in both games starts relatively close to Pareto efficiency and converges quickly to the respective Nash equilibrium.
The Conditional Nature of Democratic Compliance
Authors: Dai Xinyuan
Published: September 2006

Do democratic institutions enhance a country’s compliance with international commitments? The author develops a game-theoretic model that highlights the conditional nature of democratic institutions’ effect on compliance. Rather than assuming that the electorate in a democracy benefits from compliance uniformly, the author considers domestic distributional consequences of compliance. The model thus incorporates the preferences of competing domestic constituents as well as their politically relevant attributes such as electoral leverage and informational advantage. The model shows that, although electoral institutions intensify politicians’ accountability to domestic constituents, the direction of this electoral effect on compliance is determined by the political attributes of competing interests. The author illustrates this theory with examples of international economic and environmental policies.
The Devil You Know but Are Afraid to Face
Authors: Drakos Konstantinos , Gofas Andreas
Published: September 2006

Despite substantial progress in the applied study of terrorism, one important methodological issue has remained underdeveloped. Multiple warnings have urged for caution as the validity of extant findings may have been distorted from the well-known “devil” of underreporting bias. Yet, extant research has fallen short from addressing the issue in a systematic fashion. This article discusses a way for assessing whether underreporting is present by using the widely studied relationship between terrorism and regime type as its laboratory. After formally presenting a setup for the accommodation of underreporting bias, the authors discuss how it relates to press freedom. According to their results, underreporting is indeed present, implying that the used databases for terrorism represent an understatement of the true number of terrorist incidents.
Can We Generalize from Student Experiments to the Real World in Political Science, Military Affairs, and International Relations?
Authors: Mintz Alex , Redd Steven B. , Vedlitz Arnold
Published: September 2006

The authors conducted an experiment with a group of military officers and replicated it with a group of students at a public university in the United States. The experimental scenario dealt with a decision problem in the area of counterterrorism. The authors found that while more than one-third of students recommended doing nothing, the overwhelming majority of military officers (more than 90 percent) recommended doing something. Also, military officers exhibited less maximizing and more satisfacing decision making than students. The results show that relying on experiments with students “playing” the role of real-world national security policy makers may bias the results. The two groups are, in fact, very different. Based on student samples, it is possible to accept propositions that would not be found with samples of elite decision makers and reject propositions that may be right. However, it is possible that students can be assigned to experiments where they represent the “public” and not elites.
Structural Equivalence and International Conflict
Authors: Maoz Zeev , Kuperman Ranan D. , Terris Lesley , Talmud Ilan
Published: September 2006

The concept of international affinity—albeit under different names—captures a central place in international relations research. This study examines how different types of affinity affect the likelihood of conflict between states. The authors discuss different types of affinities as these appear in the realist and liberal paradigms. They offer a social networks conception of structural affinity—the concept of structural equivalence—which reflects the similarity of international ties across a set of different networks. They test the hypotheses derived from these paradigms, using both existing measures of affinity and their own structural equivalence measures. Their findings suggest that (1) strategic affinity has a consistent dampening effect on the probability of dyadic conflict, (2) trade-related affinity does consistently affect the probability of dyadic conflict, and (3) intergovernmental organization-related affinity has a negative impact on conflict, mostly in the twentieth century.
Diplomacy and Other Forms of Intervention in Civil Wars
Authors: Regan Patrick M. , Aydin Aysegul
Published: September 2006

Much of the empirical literature suggests that outside interventions tend to lengthen the expected duration of civil wars; conversely, the policy community often acts as if it holds the opposite expectation for the outcome of intervention. The authors argue that the divergence can be found in how models of intervention are specified in the literature. They propose a model with two novel contributions. First, they incorporate mediations as the key to resolving the strategic problems that the civil war parties face. Second, they account for the decaying effect of interventions over time. Their results suggest that diplomacy is critical for understanding the duration of civil conflicts. They find that mediation has a dramatic effect on the expected duration of a civil war and that when controlling for diplomatic efforts, economic interventions can also reduce the expected duration.
The Role(s) of Rules: Some Conceptual Clarifications
Authors: Lang Anthony , Rengger Nicholas , Walker William
Published: September 2006

This article explores the various roles that rules play in international relations. The article responds to the current international situation in which rules are being contested by numerous agents in a range of issue areas. While rules, by their very nature, will result in conflicting interpretations in social and political realms, these disagreements at the international level have the added danger of undermining international order. The article explores the nature of rules, focusing on moral and legal dimensions as they operate at the international level. We then turn to an exploration of debates about legitimacy, the impact of technology on rules and rule-making, and the dilemmas of enforcement. We conclude that while rules are a necessary part of any just political order, the dilemmas generated at the global level necessitate careful consideration of the very nature of rules. The responses to the article that follow this one seek to explore some of these issues and their relevance to more specific international issues.
The Meaning of Rules
Authors: Klabbers Jan
Published: September 2006

This article examines the interpretation of rules as an essential part of their meaning. It starts with some of the most foundational rules – pacta sunt servanda, for instance – and points to their contested nature. It looks at some of the causes of this inherent contestability and its effects on the international system. It concludes by noting that appeals to rules never settle a debate, but only begin the interpretative process that constitutes the international system. While this interpretative licence does not lead to complete anarchy, it does leave open a wide range of outcomes in rule-governed systems.
On Legitimacy
Authors: Kratochwil Friedrich
Published: September 2006

This article provides a conceptual analysis of different uses of the term ‘legitimacy’. Rather than attempting to provide a simple ‘definition’ I argue that the meaning of the concept cannot be understood in terms of a clear reference, but has to be analysed through its links with other concepts within a semantic field. In this way we are also able to ‘explain’ why at first contradictory uses of the term (designating its ‘input’ or the ‘output’ side) are part of its ‘grammar’. To that extent attempts at stipulative definitions aiming at an unequivocal sense of the term fundamentally misunderstand the function of this concept within the political discourse.
Conceptions of a Rule-Governed International Order: Europe vs. America?
Authors: Brown Chris
Published: September 2006

Differences between American and European conceptions of a rule-governed international order can be observed via an examination of the legal regimes governing the conduct of American and British troops in Iraq. In principle, the US military authorities recognise the authority of international humanitarian law with respect to, for example, the treatment of prisoners and the distinction between combatants and non-combatants, but in other respects they are able to prosecute the war against the insurgency in a conventional way. British troops, on the other hand, are obliged to act in accordance with a much more restrictive legal regime, based on changes introduced subsequent to Britain's membership of the International Criminal Court. Under this regime, British military forces in Basra are subject to much the same kind of rules concerning the use of force that govern the operation of civilian police forces in Western Europe. This ‘European’ attempt to control the way in which force is used is widely seen as a positive move in the direction of minimising the role of force in international relations – but such a judgement is questionable since there may well be circumstances where the effective use of force is both necessary and justified.
Private Authority and Legitimacy in the International System
Authors: Thirkell-White Ben
Published: September 2006

This article confronts the problem of private authorities engaging in rule-making activities for public purposes. This form of rule-making raises questions about the justice, authority and, most importantly, legitimacy of these institutional arrangements. The private authority that creates rules in the international financial system relies on claims of efficiency and expertise. These claims focus on the rules created rather than the institutions that create them, institutions that are private and thus self-interested in a different way from public authorities. The article explores these issues through a review of the role of banks that engage in rule-making at the global level.