bluuebunny/crossref_metadata_2025 huggingface dataset:
Weak with Sex: Sexual Intercourse as a Trigger for Cataplexy
Authors: Poryazova Rositsa , Khatami Ramin , Werth Esther , Bassetti Claudio L.
Published: June 2009

Introduction

Sudden, often positive emotions are typical triggers for cataplexy in patients with narcolepsy–cataplexy (NC). Cataplexy during sexual intercourse and orgasm (orgasmolepsy) has been previously reported, but its frequency and characteristics are poorly known.

Aim

To assess frequency and features of loss of muscle tone during sexual intercourse in a series of patients with NC, other sleep–wake disorders, and healthy controls.

Methods

Review of sleep questionnaires (including the Stanford Cataplexy Questionnaire) of 75 subjects (29 with NC, 26 with other sleep–wake disorders, and 20 healthy controls), followed by an interview with specific focus on muscle loss during sexual activity in suspicious cases.

Main Outcome Measures

Cataplexy during sexual intercourse and orgasm (orgasmolepsy).

Results

Orgasmolepsy was reported by three NC patients (two female, one male), one male patient with behaviorally induced insufficient sleep syndrome (BIISS) and cataplexy-like symptoms, and none of the healthy controls. In the two female NC patients, orgasmolepsy occurred by each sexual intercourse, and the male patient reported orgasmolepsy only when in a relationship involving emotional commitment and trust. In the patient with BIISS and orgasmolepsy, cataplexy-like symptoms involved unilaterally upper or lower limbs in association with negative emotions or sports activities.

Conclusions

Cataplexy during sexual intercourse is a distinct feature of NC, which can, however, be reported rarely also by patients with other sleep–wake disorders. Insufficient arousal may favor the occurrence of cataplexy and cataplexy-like symptoms, including orgasmolepsy. Hypocretin deficiency and reward dysregulation in narcolepsy may further facilitate this phenomenon and contribute to its repetitive occurrence.
1 Gyr in the life of the globular cluster NGC 6397
Authors: Heggie Douglas C. , Giersz Mirek
Published: June 2009

M4 and NGC 6397 are two very similar galactic globular clusters, which differ mainly in their surface brightness profile. M4 has a classic King-like profile, whereas NGC 6397 has a more concentrated profile, which is often interpreted as that of a post-core collapse cluster. In previous papers, however, the authors found that M4 is also a post-core collapse cluster, and concluded that the main reason for the difference between the two surface brightness profiles is fluctuations. This conclusion was reached on the basis of Monte Carlo models, however, and in the present Letter we verify that similar fluctuations occur in N-body models. The models were initialized by generating initial conditions from the Monte Carlo model of NGC 6397 at the simulated age of 12 Gyr, and one was followed for 1 Gyr. The new models help us to clarify the nature of the fluctuations, which have the nature of semiregular oscillations with a time-scale of the order of 108 years. They are influenced by the dynamical role which is played by primordial binaries in the evolution of the core.
Evaluation of Two New Smoothing Methods in Equating: The Cubic B‐Spline Presmoothing Method and the Direct Presmoothing Method
Authors: Cui Zhongmin , Kolen Michael J.
Published: June 2009

This article considers two new smoothing methods in equipercentile equating, the cubic B‐spline presmoothing method and the direct presmoothing method. Using a simulation study, these two methods are compared with established methods, the beta‐4 method, the polynomial loglinear method, and the cubic spline postsmoothing method, under three sample sizes (300, 1,000, and 3,000) and for three test content areas (ITBS Maps and Diagrams, ITBS Reference and Materials, and ITBS Capitalization). Ten thousand random samples were simulated from population distributions, and the standard error, bias, and RMSE statistics were calculated. The cubic B‐spline presmoothing method performed well in reducing total error of equating, whereas the direct presmoothing method appeared to need some modification for it to be as accurate as other smoothing methods.
Hierarchical Generalized Linear Models for the Analysis of Judge Ratings
Authors: Muckle Timothy J. , Karabatsos George
Published: June 2009

It is known that the Rasch model is a special two‐level hierarchical generalized linear model (HGLM). This article demonstrates that the many‐faceted Rasch model (MFRM) is also a special case of the two‐level HGLM, with a random intercept representing examinee ability on a test, and fixed effects for the test items, judges, and possibly other facets. This perspective suggests useful modeling extensions of the MFRM. For example, in the HGLM framework it is possible to model random effects for items and judges in order to assess their stability across examinees. The MFRM can also be extended so that item difficulty and judge severity are modeled as functions of examinee characteristics (covariates), for the purposes of detecting differential item functioning and differential rater functioning. Practical illustrations of the HGLM are presented through the analysis of simulated and real judge‐mediated data sets involving ordinal responses.
Assessing Differential Prediction of College Grades by Race/Ethnicity with a Multilevel Model
Authors: Culpepper Steven A. , Davenport Ernest C.
Published: June 2009

Previous research notes the importance of understanding racial/ethnic differential prediction of college grades across multiple institutions. Institutional variation in selection indices is especially important given some states’ laws governing public institutions’ admissions decisions. This paper employed multilevel moderated multiple regression to study the variation of selection indices across 30 institutions and the accuracy of selection indices in predicting college grades for students of different racial/ethnic backgrounds. Several benefits of multilevel models for cross‐institutional differential prediction studies were described and include: controlling for institutional differences in range restriction, providing reliability estimates of least squares estimates, and adjusting criterion scores for differences in coursework difficulty. The findings from this study provide evidence of institutional variation in selection indices, which challenges current laws aimed at standardizing them. Specifically, there was evidence that the predictor slope coefficients varied across institutions, in addition to the estimates that measured intercept differences for African and Asian American students. Across universities, the results mirrored previous findings: high school grade point average (GPA) differentially predicted grades for African Americans, SAT verbal scores differentially predict grades for Asian Americans, and SAT math scores were better predictors of Asian Americans’ grades.
Medicare Reform Preferences: Before and After Education and Deliberation
Authors: WOOLSEY SAMANTHA
Published: June 2009

Using the case of Medicare reform, this article provides data on whether certain deliberative democracy efforts result in higher quality public opinion. Through a survey of preexisting social groups before and after a review of educational materials and participation in group discussion, the study hypothesized that: (1) respondents would change their reform preferences due to participation in an educational and deliberative forum; and (2) respondents' reform and value preferences would be more congruent after the forum than they were before it. Results supported these hypotheses. Reform preference changes were influential in terms of overall public opinion. In three cases, opinion changes resulted in the majority response changing from opposition or uncertainty to support. In other instances, preference change was evident in the magnitude of support indicated for particular reform proposals. Congruence between respondent value preferences and related reform proposals increased for all five major policy variables and their corresponding values, indicating higher quality opinion.

Utilizando el caso de la reforma al sistema de salud, este artículo provee información acerca de si algunos foros de democracia deliberativa ocasionan una mayor calidad de la opinión pública. A través de una encuesta a grupos sociales pre‐existentes antes y después de la revisión de los materiales educacionales y participación en la discusión de grupo, el estudio plantea que: (1) los encuestados cambiarían sus preferencias de reforma debido a la participación en un foro educacional y deliberativo; y (2) las preferencias y valores de reforma de los encuestados serían más congruentes después del foro que antes del mismo. Los resultados apoyaban estas hipótesis. Los cambios en las preferencias de reforma fueron influyentes en términos del conjunto de la opinión pública. En tres casos, los cambios de la opinión resultaron en que la respuesta de la mayoría cambiara de la oposición o indecisión al apoyo. Por otro lado, el cambio en la preferencia fue evidente en la magnitud del apoyo indicado para una propuesta de reforma particular. La congruencia entre el valor de la preferencia del encuestado y las propuestas de reforma relacionadas incrementó en todas las cinco variables políticas más importantes y sus valores correspondientes, indicando una mayor calidad de la opinión.
U.S. Security and Border Protection Policy before and after 9/11: A Policy Impact Assessment
Authors: Ramírez Héctor Ramón
Published: June 2009

This study utilizes key analytical concepts from complex interdependence theory to examine the impact of U.S. security and border protection policy on the U.S.–Mexico land border before and after 9/11. It seeks to answer whether post‐9/11 U.S. security and border protection policy responses make any difference to the protection of the U.S.–Mexican land border. The results of the analysis demonstrate that, other things being equal, post‐9/11 U.S. security and border protection policy responses have had only marginal effects on the protection of the U.S.–Mexican land border compared to the pre‐9/11 period. In other words, those policy responses make little difference when their performance is compared before and after 9/11. I conclude that the U.S.–Mexico land border is more secure, but is not completely safe in the aftermath of 9/11.

Este estudio utiliza conceptos analíticos claves de la teoría de interdependencia compleja para examinar el impacto de la seguridad estadounidense y la política de protección de la frontera en la tierra límite de E.U.–México antes y después del 11/9. Busca responder si las respuestas de seguridad estadounidense y políticas de protección posteriores hicieron alguna diferencia en la protección de la frontera de E.U.–México. Los resultados del análisis demuestran que, ceteris paribus, la seguridad estadounidense y las respuestas de protección fronteriza posteriores han tenido sólo efectos marginales en la protección de la misma comparados con el periodo anterior. En otras palabras, estas políticas de respuesta hicieron poca diferencia después del 11/9 en comparación con las condiciones que prevalecían antes de 11/9. Concluyo que la frontera E.U.–México es más segura, pero no completamente en el contexto que dejó el 11/9.
Performance of influenza rapid point‐of‐care tests in the detection of swine lineage A(H1N1) influenza viruses
Authors: Hurt Aeron C. , Baas Chantal , Deng Yi‐Mo , Roberts Sally , Kelso Anne , Barr Ian G.
Published: June 2009

Background  In April 2009, an A(H1N1) influenza virus of swine lineage was detected in humans in the USA, and in just over a month has infected over 10 000 people in more than 40 countries.

Objectives  To determine the performance of the Binax Now, BD Directigen EZ, and the Quidel QuickVue influenza rapid point‐of‐care (POC) tests for the detection of the recently emerged swine lineage A(H1N1) virus.

Methods  Swine lineage A(H1N1) and human seasonal influenza strains were cultured and then diluted to specific infectivity titres. Viral dilutions were assayed by the rapid POC tests and by real‐time RT‐PCR.

Results  All three of the rapid POC tests successfully detected the swine lineage A(H1N1) viruses at levels between 103 and 105 TCID50/ml (tissue culture infectious dose50), with the BD Directigen test demonstrating marginally greater sensitivity than the other two tests. Viral infectivity and RNA load data for viruses at the detection limit of the rapid test kits, suggested that both the Quidel and the Binax tests were less sensitive for the detection of swine lineage A(H1N1) viruses than for human seasonal strains. In comparison the BD Directigen demonstrated similar sensitivity when detecting swine lineage A(H1N1) and human seasonal viruses.

Conclusions  The three rapid POC tests all detected the emergent swine lineage A(H1N1) virus when it was present at high virus concentrations. Early diagnosis of infection can assist in the rapid treatment. However the tests are significantly less sensitive than PCR assays and as such, negative results should be verified by a laboratory test.
What heat is telling us about microbial conversions in nature and technology: from chip‐ to megacalorimetry
Authors: Maskow Thomas , Kemp Richard , Buchholz Friederike , Schubert Torsten , Kiesel Baerbel , Harms Hauke
Published: June 2009

The exploitation of microorganisms in natural or technological systems calls for monitoring tools that reflect their metabolic activity in real time and, if necessary, are flexible enough for field application. The Gibbs energy dissipation of assimilated substrates or photons often in the form of heat is a general feature of life processes and thus, in principle, available to monitor and control microbial dynamics. Furthermore, the combination of measured heat fluxes with material fluxes allows the application of Hess' law to either prove expected growth stoichiometries and kinetics or identify and estimate unexpected side reactions. The combination of calorimetry with respirometry is theoretically suited for the quantification of the degree of coupling between catabolic and anabolic reactions. New calorimeter developments overcome the weaknesses of conventional devices, which hitherto limited the full exploitation of this powerful analytical tool. Calorimetric systems can be integrated easily into natural and technological systems of interest. They are potentially suited for high‐throughput measurements and are robust enough for field deployment. This review explains what information calorimetric analyses provide; it introduces newly emerging calorimetric techniques and it exemplifies the application of calorimetry in different fields of microbial research.
Reactive oxygen‐derived free radicals are key to the endothelial dysfunction of diabetes
Authors: SHI Yi , VANHOUTTE Paul Michel
Published: June 2009

Vascular complications are an important pathological issue in diabetes that lead to the further functional deterioration of several organs. The balance between endothelium‐dependent relaxing factors and endothelium‐dependent contracting factors (EDCFs) is crucial in controlling local vascular tone and function under normal conditions. Diabetic endothelial dysfunction is characterized by reduced endothelium‐dependent relaxations and/or enhanced endothelium‐dependent contractions. Elevated levels of oxygen‐derived free radicals are the initial source of endothelial dysfunction in diabetes. Oxygen‐derived free radicals not only reduce nitric oxide bioavailability, but also facilitate the production and/or action of EDCFs. Thus, the endothelial balance tips towards vasoconstrictor responses over the course of diabetes.
Improvement of cardiovascular risk assessment in Type 2 diabetes by the addition of carotid artery intima–media thickness to Framingham risk score: A retrospective cohort study
Authors: ATAOGLU Hayriye Esra , SALER Tayyibe , UZUNHASAN Isil , YENIGUN Mustafa , YIGIT Zehra , TEMIZ Levent Umit , SAGLAM Zuhal , CETIN Faik , KUMBASAR Baki , SAR Fuat
Published: June 2009

Background:  The intima–media thickness (IMT) of the carotid artery is highly correlated with cardiovascular events in Type 2 diabetes mellitus (T2DM). The aim of the present study was to undertake a cardiovascular risk assessment in a group of patients (n = 102) who had been followed‐up for 10 years.

Methods:  Framingham risk score (FRS), IMT, and various other clinical parameters were evaluated retrospectively using Student’s t‐test, regression analysis, and χ2 tests. Primary endpoints were defined as cardiovascular death, non‐fatal myocardial infarction, angina, and ischemic stroke.

Results:  The IMT (1.09 ± 0.32 vs 0.89 ± 0.25; P < 0.001) and percentage coronary risk as determined by the FRS (24.33 ± 11.07 vs 16.54 ± 8.35; P = 0.001) were significantly higher in patients presenting with any of the primary endpoints compared with patients in whom no cardiovascular morbidity or mortality was recorded. Other factors that significantly predicted cardiovascular mortality and morbidity included diastolic blood pressure and urinary albumin excretion (UAE; P < 0.001). The likelihood of primary endpoints could be predicted by UAE >30 mg/day, carotid artery IMT ≥0.9 mm, and FRS ≥20 (odds ratios 8.800, 3.377, and 2.807, respectively).

Conclusion:  Although FRS predicts 10‐year risk for cardiovascular mortality and morbidity in T2DM, we suggest that UAE and carotid artery IMT should also be considered in risk assessments.
The critical role of alpha‐folate receptor in the resistance of melanoma to methotrexate
Authors: Sánchez‐del‐Campo Luís , Montenegro María F. , Cabezas‐Herrera Juan , Rodríguez‐López José Neptuno
Published: June 2009

Although methotrexate (MTX) is an effective drug for several types of cancer, it is not active against melanoma. Experiments following methotrexate treatment indicated a reduced accumulation of the drug in the cytosolic compartment in melanoma cells, suggesting that the mechanisms that control the transport and retention of this drug could be altered in melanoma. For this reason, we analyzed the presence and function of folate receptor‐α (FRα) in melanoma cells. In this study, we have identified the presence of FRα in normal and pathological melanocytes and demonstrated that MTX is preferentially transported through this receptor in melanoma cells. FRα‐induced endocytic transport of MTX, together with drug melanosomal sequestration and cellular exportation, ensures reduced accumulation of this cytotoxic compound in intracellular compartments. The critical role of FRα in this mechanism of resistance and the therapeutic consequences of these findings are also discussed.
Future energy potential of Miscanthus in Europe
Authors: HASTINGS ASTLEY , CLIFTON‐BROWN JOHN , WATTENBACH MARTIN , MITCHELL C. PAUL , STAMPFL PAUL , SMITH PETE
Published: June 2009

European field experiments have demonstrated Miscanthus can produce some of the highest energy yields per hectare of all potential energy crops. Previous modelling studies using MISCANMOD have calculated the potential energy yield for the EU27 from mean historical climate data (1960–1990). In this paper, we have built on the previous studies by further developing a new Miscanthus crop growth model MISCANFOR in order to analyse (i) interannual variation in yields for past and future climates, (ii) genotype‐specific parameters on yield in Europe. Under recent climatic conditions (1960–1990) we show that 10% of arable land could produce 1709 PJ and mitigate 30 Tg of carbon dioxide‐carbon (CO2‐C) equivalent greenhouse gasses (GHGs) compared with EU27 primary energy consumption of 65 598 PJ, emitting 1048 Tg of CO2‐C equivalent GHGs in 2005. If we continue to use the clone Miscanthus×giganteus, MISCANFOR shows that, as climate change reduces in‐season water availability, energy production and carbon mitigation could fall 80% by 2080 for the Intergovernmental Panel on Climate Change A2 scenario. However, because Miscanthus is found in a huge range of climates in Asia, we propose that new hybrids will incorporate genes conferring superior drought and frost tolerance. Using parameters from characterized germplasm, we calculate energy production could increase from present levels by 88% (to 2360 PJ) and mitigate 42 Tg of CO2‐C equivalent using 10% arable land for the 2080 mid‐range A2 scenario. This is equivalent to 3.6% of 2005 EU27 primary energy consumption and 4.0% of total CO2 equivalent C GHG emissions.
Pharmacodynamics of SMP-601 (PTZ601) against Vancomycin-ResistantEnterococcus faeciumand Methicillin-ResistantStaphylococcus aureusin Neutropenic Murine Thigh Infection Models
Authors: Eguchi Ken , Kanazawa Katsunori , Eriguchi Yoshiro , Ueda Yutaka
Published: June 2009

SMP-601 (also known as PTZ601, PZ-601, or SM-216601) is a novel parenteral carbapenem with potent activity against multidrug-resistant gram-positive pathogens, including vancomycin-resistantEnterococcus faecium(VREF) and methicillin-resistantStaphylococcus aureus(MRSA). The pharmacodynamics of SMP-601 against VREF and MRSA were investigated in neutropenic murine thigh infection models. The percentage of the dosing interval that the unbound SMP-601 concentration exceeded the MIC (f%T>MIC) was the pharmacokinetic-pharmacodynamic parameter that correlated most closely with efficacy withR2values of 0.81 to 0.84 for two strains of VREF and 0.92 to 0.93 for two strains of MRSA, whereas theR2values for the area under the concentration-time curve from 0 to 24 h divided by the MIC were 0.12 to 0.89, and theR2values for the peak level divided by the MIC were 0 to 0.22. Thef%T>MIC levels required for static or killing efficacy against two strains of VREF (9 to 19%) apparently were lower than those against two strains of MRSA (23 to 37%). These results suggested that SMP-601 showed time-dependent in vivo efficacy against VREF and MRSA, and SMP-601 had a sufficient therapeutic effect against VREF infections at lower exposure conditions compared to those for with MRSA infections.
The Capability of Catabolic Utilization of
N
-Acetylneuraminic Acid, a Sialic Acid, Is Essential for
Vibrio vulnificus
Pathogenesis
Authors: Jeong Hee Gon , Oh Man Hwan , Kim Byoung Sik , Lee Min Young , Han Ho Jae , Choi Sang Ho
Published: June 2009

N
-acetylneuraminic acid (Neu5Ac, sialic acid) could provide a good substrate for enteropathogenic bacteria in the intestine, when the bacteria invade and colonize in human gut. In order to analyze the role of Neu5Ac catabolism in
Vibrio vulnificus
pathogenesis, a mutant with disruption of the
nanA
gene encoding Neu5Ac lyase was constructed by allelic exchanges. The
nanA
mutant was not able to utilize Neu5Ac as a sole carbon source and revealed an altered colony morphotype with reduced opacity in the presence of Neu5Ac. Compared to the wild type, the
nanA
mutant exhibited a low level of cytotoxicity toward INT-407 epithelial cells in vitro and reduced virulence in a mouse model. The disruption of
nanA
also resulted in a substantial decrease in histopathological damage in jejunum and colon tissues from the mouse intestine. These results indicated that NanA plays an important role in
V. vulnificus
pathogenesis. In addition, the
nanA
mutant was significantly diminished in growth with and adherence to INT-407 epithelial cells in vitro, and was defective for intestinal colonization, reflecting the impaired ability of the mutant to grow and survive with, persist in, and adhere to the intestine in vivo. Consequently, the combined results suggest that NanA and the capability of catabolic utilization of Neu5Ac contribute to
V. vulnificus
virulence by ensuring growth, adhesion, and survival during infection.
Interval-Specific Congenic Lines Reveal Quantitative Trait Loci with Penetrant Lyme Arthritis Phenotypes on Chromosomes 5, 11, and 12
Authors: Ma Ying , Miller Jennifer C. , Crandall Hillary , Larsen Eric T. , Dunn Diane M. , Weiss Robert B. , Subramanian Meenakumari , Weis John H. , Zachary James F. , Teuscher Cory , Weis Janis J.
Published: June 2009

The observation thatBorrelia burgdorferi-induced arthritis is severe in C3H mice and milder in C57BL/6 (B6) mice has allowed a forward genetics approach for the identification of genetic elements that regulate the arthritis response. Quantitative trait loci (QTL) on five chromosomes (Chr) were identified previously in segregating crosses between C3H and B6 mice and collectively designatedB. burgdorferiarthritis-associated (Bbaa) QTL. Reciprocal interval-specific congenic lines (ISCL) that encompassBbaa1,Bbaa2-Bbaa3,Bbaa4,Bbaa6, andBbaa12on Chr 4, 5, 11, 12, and 1, respectively, have now been generated. Bidirectional transfer of the arthritis severity phenotype in association withBbaa2-Bbaa3andBbaa4was observed, and unidirectional transfer with the B6 allele ofBbaa6was noted. These findings confirm the existence of polymorphic loci withinBbaa2-Bbaa3,Bbaa4, andBbaa6that regulate the severity ofB. burgdorferi-induced arthritis. ISCL were used to assess the regulation of a previously identified interferon transcriptional profile associated with severe disease in C3H mice. The regulation of this transcriptional signature was found to be independent of penetrantBbaaQTL, both in joint tissues and in isolated macrophages. These results clearly demonstrate the utility of forward genetics for the discovery of novel genes and pathways involved in the regulation of the severity of Lyme arthritis and predict the involvement of regulatory elements not evident from other experimental approaches.
A Genetically Engineered Live Attenuated Vaccine ofCoccidioides posadasiiProtects BALB/c Mice against Coccidioidomycosis
Authors: Xue Jianmin , Chen Xia , Selby Dale , Hung Chiung-Yu , Yu Jieh-Juen , Cole Garry T.
Published: June 2009

Coccidioidomycosis (also known as San Joaquin Valley fever) is an occupational disease. Workers exposed to outdoor dust which contains spores of the soil-inhabiting fungus have a significantly increased risk of respiratory infection. In addition, people with compromised T-cell immunity, the elderly, and certain racial groups, particularly African-Americans and Filipinos, who live in regions of endemicity in the southwestern United States have an elevated incidence of symptomatic infection caused by inhalation of spores ofCoccidioides posadasiiorCoccidioides immitis. Recurring epidemics and escalation of medical costs have helped to motivate production of a vaccine against valley fever. The major focus has been the development of a defined, T-cell-reactive, recombinant protein vaccine. However, none of the products described to date have provided full protection to coccidioidal disease-susceptible BALB/c mice. Here we describe the first genetically engineered, live, attenuated vaccine that protects both BALB/c and C57BL/6 mice against coccidioidomycosis. Two chitinase genes (CTS2andCTS3) were disrupted to yield the attenuated strain, which was unable to endosporulate and was no longer infectious. Vaccinated survivors mounted an immune response characterized by production of both T-helper-1- and T-helper-2-type cytokines. Histology revealed well-formed granulomas and markedly diminished inflammation. Significantly fewer organisms were observed in the lungs of survivors than in those of nonvaccinated mice. Additional investigations are required to further define the nature of the live, attenuated vaccine-induced immunity againstCoccidioidesinfection.
GHOST-FREE HIGHER DERIVATIVE QUANTUM GRAVITY, THE HIERARCHY AND THE COSMOLOGICAL CONSTANT PROBLEMS
Authors: TKACH V. I.
Published: June 2009

We propose a new solution to problems of the hierarchy and smallness of the cosmological constant using the TeV scale of the Standard Model in a new framework of the higher-order gravity.
ELECTRO MECHANICAL AND IMPEDANCE STUDIES OF (Na1-xKx)1/2Bi1/2TiO3
Authors: VIJAYA BHASKAR RAO P. , BHIMA SANKARAM T.
Published: June 2009

Ceramic samples of [( Na 1-x K x)1/2 Bi 1/2 TiO 3] (NKBT) (x = 0.1, 0.15, 0.2, 0.3, 0.45) were prepared by double sintering method. The admittance measurements were carried out in the frequency range of 1 KHz to 10 MHz in the temperature range of 30°C–600°C. The dielectric nature as deduced from admittance data shows a strong temperature and frequency dependence, apart from the relaxor behavior. The admittance data was analyzed by complex plane diagrams i.e., Y′ versus Y′′ at different temperature. The frequency explicit plots of imaginary component of electric modulus (M′′) at various temperatures show peaks shifting to higher frequencies with temperature (> 400° C ). The relaxation peaks were effected by the doping. The activation energies are obtained from the data. The electromechanical coefficients KP, K31 were calculated from the resonant and anti-resonant frequencies obtained from vector admittance plots. The temperature dependence of electromechanical coefficients is studied. The solid solution samples show higher KP, K31 values as compared to pure sodium bismuth titanate.
INTERSUBBAND OPTICAL ABSORPTION IN CYLINDRICAL QUANTUM DOT QUANTUM WELL
Authors: WANG RUI-ZHEN , GUO KANG-XIAN , CHEN BIN , ZHENG YUN-BAO
Published: June 2009

The intersubband optical absorption in cylindrical quantum dot quantum well (QDQW) for different sizes of QDQW is theoretically studied. The analytical expression of the absorption coefficient is derived by using the compact density-matrix approach and the iterative method. And the numerical calculations are presented for a typical GaAs / AlGaAs QDQW. The results obtained show that the optical absorption coefficient in the QDQW can be importantly modified by size of shell well. Moreover, they also show that the optical absorption is strongly dependent on the incident optical intensity.
A NEW SOLITON HIERARCHY AND ITS TWO KINDS OF EXPANDING INTEGRABLE MODELS AS WELL AS HAMILTONIAN STRUCTURE
Authors: ZHANG YUFENG , DONG HUANHE , HON Y. C.
Published: June 2009

With the help of two different Lie algebras and the corresponding loop algebras, the first and second kind of expanding integrable models of a new soliton hierarchy of evolution equations are obtained, respectively. The Hamiltonian structure of the first one is worked out by the quadratic-form identity. The bi-Hamiltonian structure of the second one is also generated. From the paper, we conclude that various Lie algebras really produce different soliton hierarchies of evolution equations. The approach presented in the paper provides a way for generating different integrable soliton expanding systems of the known soliton hierarchy of equations.
EFFECT OF ATTACK ON SCALE-FREE NETWORKS DUE TO CASCADING FAILURE
Authors: WANG JIAN-WEI , RONG LI-LI , ZHANG LIANG
Published: June 2009

In this paper, based on the local preferential redistribution rule of the load after removing a node, we propose a cascading model and explore cascading failures on scale-free networks. Assuming that a failed node leads only to a redistribution of the load passing through it to its neighboring nodes, we study the response of scale-free networks subject to attacks on nodes. The network robustness against cascading failures is quantitatively measured by the critical threshold Tc, at which a phase transition occurs from normal state to collapse. For each case of attacks on nodes, four different attack strategies are used: removal by the descending order of the degree, attack by the ascending order of the degree, random removal of breakdown, and removal by the ascending order of the average degree of neighboring nodes of a broken node. Compared with the previous result, i.e. the robust-yet-fragile property of scale-free networks on random failures of nodes and intentional attacks, our cascading model has totally different and interesting results. On the one hand, as unexpected, choosing the node with the lowest degree is more efficient than the one with the highest degree when α < 1, which is a tunable parameter in our model. On the other hand, the robustness against cascading failures and the harm order of four attack strategies strongly depends on the parameter α. These results may be very helpful for real-life networks to protect the key nodes and avoid cascading-failure-induced disasters.
EXPERIMENTAL VERIFICATION OF CUMULATIVE SECOND-HARMONIC GENERATION BY SHEAR HORIZONTAL MODE PROPAGATION IN AN ELASTIC PLATE
Authors: DENG MING-XI
Published: June 2009

Primary shear horizontal (SH) mode propagation and its second harmonic are generated and detected using wedge transducers on the surface of an elastic plate. In the far field region, the clear second-harmonic response can be observed at the frequency where the phase velocity of the primary SH mode equals that of the symmetric double-frequency Lamb mode. Based on the measured results, the ratio of the second-harmonic amplitude to the square of the primary SH mode amplitude is numerically evaluated for different propagation distances. It is experimentally verified that under some conditions the second harmonic of the primary SH mode propagation grows in amplitude with propagation distance.
SPIN DIFFUSION COEFFICIENT OF A1-PHASE OF SUPERFLUID 3He AT LOW TEMPERATURES
Authors: AFZALI R. , PASHAEE F.
Published: June 2009

The spin diffusion coefficient tensor of the A1-phase of superfluid 3 He at low temperatures and melting pressure is calculated using the Boltzmann equation approach and Pfitzner procedure. Then considering Bogoliubov-normal interaction, we show that the total spin diffusion is proportional to 1/T2, the spin diffusion coefficient of superfluid component [Formula: see text] is proportional to T-2, and the spin diffusion coefficient of super-fluid component [Formula: see text] is independent of temperature. Furthermore, it is seen that superfluid components play an important role in spin diffusion of the A1-phase.
OPTIMIZATION OF EMBEDDED CONTROLLERS BASED ON REDUNDANT TRANSITION REMOVAL AND FAULT SIMULATION USING K-WISE TESTS
Authors: GÖREN SEZER
Published: June 2009

This paper presents an efficient redundancy removal technique for hierarchical optimization of FSM networks. In this technique, we first remove redundant transitions from the state transition graph (STG) of the driven FSM, M2, of the cascaded network by applying a reachability analysis to the composite machine, M1 → M2, once and for all. Then, a k-wise complete test suite for M2 is generated from the new STG of the driven FSM. Redundancy identification consists of two phases. In the first phase, almost all of the detectable stuck-at faults are identified by fault simulation using the k-wise test suite. During the second phase, each fault f that is undetected by k-wise tests is injected in M2 to obtain [Formula: see text] in the topologically sorted order one by one. Then the equivalence check of two FSMs M2 and [Formula: see text] in the environment where [Formula: see text] is driven by M1 is done. If a fault is found to be undetectable in the second phase, it is a redundant fault and kept in M2 ([Formula: see text] is taken as M2). Finally, simultaneous removal of redundant faults is done at logic level. We present experimental results to provide a comparison of the data produced by the state-of-the-art FSM network optimizer and show the effectiveness of our approach.
ELECTRONICALLY TUNABLE CURRENT-MODE UNIVERSAL BIQUAD FILTER USING DUAL-X CURRENT CONVEYORS
Authors: MINAEI SHAHRAM
Published: June 2009

In this paper, an electronically tunable current-mode (CM) universal biquad filter is proposed. The proposed filter employs three dual-X second-generation current conveyors (DXCCIIs), two grounded capacitors and four NMOS transistors acting as resistors. The proposed filter simultaneously realizes standard filter functions such as low-pass (LP), band-pass (BP), and high-pass (HP) responses. The notch (NH) and all-pass (AP) functions can also be obtained by connecting appropriate output currents directly without using additional active elements. The output signals are obtained at high output impedance terminals, which is important for easy cascading in CM operation. SPICE simulation results are given to verify the theoretical analyses.
ON THE NONLINEAR MODELING OF RING OSCILLATORS
Authors: ELWAKIL A. S. , SALAMA K. N.
Published: June 2009

We develop higher-order nonlinear models of three-stage and five-stage ring oscillators based on a novel inverter model. The oscillation condition and oscillation frequency are derived and compared to classical linear model analysis. Two important special cases for five-stage ring oscillators are also studied. Numerical simulations are shown.
EXPLORATION OF POWER-DELAY TRADE-OFFS WITH HETEROGENEOUS ADDERS BY INTEGER LINEAR PROGRAMMING
Authors: KWAK SANGHOON , LEE JEONG-GUN , JUNG EUN-GU , HAR DONGSOO , ERCEGOVAC MILOS D. , LEE JEONG-A
Published: June 2009

The performance of arithmetic adders varies widely in their power consumption, delay, and area requirements. To acquire more fine-grained trade-offs in the power-delay trade-off curve of a binary adder, the heterogeneous adder architecture is adopted. In heterogeneous adder architecture, a binary adder is decomposed into sub-adder blocks with different carry propagation schemes and bit-widths. Thus the method allows us to expand the original design space of a specific type of adder into the more fine-grained design space by mixing that of each sub-adder. In this paper, a design for heterogeneous adder through power optimization under delay constraints or delay optimization under power constraints was presented by determining the bit-width of each sub-adder. Also the effectiveness of the proposed method was demonstrated by showing the ratio of the power consumption of heterogeneous adder to that of conventional adder.
DESIGN OF A VLSI HAMMING NEURAL NETWORK FOR ARRHYTHMIA CLASSIFICATION
Authors: GHANAVTI BEHZAD , SHOMALNASAB GHOLAMREZA
Published: June 2009

The implantable cardioverter defibrillators (ICDs) detect and treat dangerous cardiac arrhythmia. This paper describes a VLSI neural network chip to be implemented using 0.35 μ CMOS technology which acts as an intercardia tachycardia classification system. The Hamming network used to classify non binary input pattern and also reduce impact of noise, drift and offset inherent in analog application.

Simulation result using HSPICE and level 49 parameters (BSIM3V3) that verify the functionality of circuit are presented.
INFLUENCE OF CURVATURE OF GRAPHENE LAYERS OF MULTI-WALLED CARBON NANOTUBES ON ELECTRICAL PROPERTIES
Authors: ROMANENKO A. I. , ANIKEEVA O. B. , BURYAKOV T. I. , TKACHEV E. N. , ZHDANOV K. R. , KUZNETSOV V. L. , USOLTSEVA A. N. , ISCHENKO A. V.
Published: June 2009

We investigated temperature and magnetic field dependences of conductivity of multi-walled carbon nanotubes (MWNTs) with different average outer diameter. We separated out the quantum corrections to magnetoconductivity for interaction electrons and determined the dependence of constant of electron–electron interaction λ versus curvature of graphene layers in MWNTs.
DENSITY FUNCTIONAL STUDY ON THE EFFECT OF ELECTRON WITHDRAWING SUBSTITUENT ON THE STABILITY OF RNHBH2
Authors: JUNG DONG HYUN , KIM DAEJIN , LEE AREUM , CHOI SEUNG-HOON , KANG SANG OOK
Published: June 2009

We investigated the stability of aminoborane with electron withdrawing groups such as – CF 3 and – CN using density functional theory calculations. For the electron withdrawing groups of – CF 3 and – CN , we observed similar tendency of B – N bond strength: electron withdrawal from the N atom reduces the strength of B – N bonds. And we find that the electron density localized on B and N is also reduced through the charge analysis. These electron withdrawing substituents make cyclic dimers and trimers stabilized less than electron donating ones.
MOLECULAR DYNAMICS SIMULATION ON HYDROGEN STORAGE IN METALLIC NANOPARTICLES
Authors: OGAWA HIROSHI , TEZUKA AKINORI , WANG HAO , IKESHOJI TAMIO , KATAGIRI MASAHIKO
Published: June 2009

Hydrogen storage in a metallic nanoparticle was simulated by classical molecular dynamics. Distribution of hydrogen atoms inside nanoparticle was investigated by changing length and energy parameters of metal– H bonds. Hydrogen atoms diffused into the particle and distributed homogeneously in case of weak metal– H bonds. In case of strong metal– H bonds, a hydrogen-rich surface layer was observed which suppresses the inward diffusion of hydrogen atoms. Structural modification of nanoparticle accompanied by grain boundary formation due to hydrogen loading was also observed. These variations in dynamical and structural features are considered to affect the hydrogen storage properties in nanoparticles.
ENHANCED ACCUMULATION OF CARBOHYDRATE-DISPLAYING CdTe QUANTUM DOTS IN CELLS RESPONDING TO CELLULAR CHEMICAL STRESSES
Authors: NISHIO TAKASHI , NIIKURA KENICHI , MATSUO YASUTAKA , IJIRO KUNIHARU
Published: June 2009

We propose a novel stress sensing methods using water soluble, sugar-displaying quantum dot and digitonin-permeabilized semi-intact HeLa cells. The amount of GlcNAc -QDs (N-acetylglucosamine-displaying quantum dots) binding to heavy metal ion exposed cells was investigated by fluorescence intensity, and it increased in a dose-dependent manner. This result suggests that GlcNAc -QD could be applied for a new stress sensing probe.
SPIN-POLARIZED TRANSPORT THROUGH GaAs/AlGaAs PARABOLIC QUANTUM WELL UNDER A UNIFORM MAGNETIC FIELD
Authors: WAN F. , JALIL M. B. A. , TAN S. G. , FUJITA T.
Published: June 2009

We present a GaAs / AlGaAs -based quantum well device capable of achieving an appreciable spin polarization coupled with high electron transmission. Our numerical results indicate that the device is able to achieve a high spin polarization without the need for less commonly used materials with high g-factors required by previously proposed semiconductor-based systems. The electron transmission and spin polarization amplitude of our structure is found to be robust to the length of the parabolic well, which could ease the fabrication of such structures in practical applications.
THEORETICAL STUDY ON OPEN-SHELL NONLINEAR OPTICAL MOLECULAR SYSTEMS AND A DEVELOPMENT OF A NOVEL COMPUTATIONAL SCHEME OF EXCITON DYNAMICS
Authors: NAKANO MASAYOSHI , KISHI RYOHEI , FUKUI HITOSHI , MINAMI TAKUYA , NAGAI HIROSHI , YONEDA KYOHEI , BONNESS SEAN , TAKAHASHI HIDEAKI
Published: June 2009

This contribution firstly elucidates a structure–property relationship in third-order nonlinear optical molecular systems with singlet diradical characters. It turns out that the second hyperpolarizabilities (γ) of the singlet open-shell molecules with intermediate diradical characters are significantly enhanced as compared with those of closed-shell and pure diradical molecules. The hybrid density functional theory method, i.e. UBHandHLYP, is applied to the calculations of γ of dimer models composed of singlet diradical diphenalenyl molecules, which show a remarkable enhancement of γ per monomer as decreasing the intermolecular distance. The second contribution is concerned with a development of ab initio molecular orbital configuration-interaction-based quantum master equation (QME) approach. This is found to provide both coherent processes, e.g. dynamic polarization and exciton (electron–hole pair) recurrence motion, and incoherent processes, e.g. exciton migration, in molecular systems. Using this approach, the electron/hole dynamics for dynamic polarizabilities α(ω) are examined for several π-conjugated linear chain systems, and the structural dependences of α(ω) are elucidated.
HIGHLY ORDERED MICRO-ARRAYS OF CdSe QUANTUM DOTS ON CHEMICALLY PATTERNED SUBSTRATES
Authors: ZHANG LI , SI HUA-YAN , XU HUA , ZHANG HAO-LI , XIONG YU-QING
Published: June 2009

Highly ordered arrays consisting uniform fluorescent cadmium selenide ( CdSe ) quantum dots (QDs) ring or dot structures were obtained by self-assembly of QDs on chemically patterned substrates. In this method, Au substrates with alternating hydrophobic and hydrophilic square patterns are firstly fabricated by microcontact printing, which allows water droplets to condense on the hydrophilic regions to provide two-dimensional template arrays. The CdSe QDs are then assembled at the liquid/liquid interfaces to give uniform micro or nanostructures. The shape and size of the rings and dots can be tailored by controlling the relative evaporation speed of the water and the organic solvents. The obtained nanostructures have ideal topography to avoid substrate-induced fluorescence quenching.
THERMODYNAMICS AND HYDROGEN STORAGE ABILITY OF BINARY HYDROGEN + HELP GAS CLATHRATE HYDRATE
Authors: BELOSLUDOV V. R. , SUBBOTIN O. S. , BELOSLUDOV R. V. , MIZUSEKI H. , KAWAZOE Y. , KUDOH J.
Published: June 2009

Storage of hydrogen as hydrogen hydrate is a promising alternative technology to liquefied hydrogen at cryogenic temperatures or compressed hydrogen at high pressures. In this paper, computer simulation is performed based on the solid solution theory of clathrates of van der Waals and Platteeuw with some modifications that include in particular the account of multiple cage occupancies and host relaxation. The quasiharmonic lattice dynamics method employed here gives the free energy of clathrate hydrate to first order in the anharmonicity of intermolecular potential and permits to take into account quantum zero-point vibration of host lattice and hydrogen in the cages. It is employed to study the thermodynamic functions of binary (mixed) H 2– CH 4 hydrates of cubic structure II (sII) and hexagonal structure H (sH). It is shown that at divariant equilibrium "gas phase–gas hydrate" with increasing pressure the filling of large cavities by hydrogen proceeds gradually from single filling to the maximal number of hydrogen molecules in clusters included in large cages (four in sII and five in sH) preserving stability of the hydrogen–methane hydrates sII and sH. The results show that mass fraction of hydrogen in the mixed sH hydrate is significantly lower than in the mixed sII hydrate. Pressure of monovariant equilibrium " IceI h–gas phase–mixed sII hydrate" with increasing methane concentration in the gas phase lowers in comparison with the pressure of pure hydrogen hydrate formation. For the mixed hydrogen + methane sH hydrates, it was demonstrated that thermodynamic stability depends on the filling degree of small cavities by methane molecules and stability area shifts to lower pressure with increasing filling.
PREPARATION AND CHARACTERIZATION OF SILVER PALMITATE
Authors: LI YALING , WANG SHUI , YANG XIAOLING , ZHANG XU
Published: June 2009

In order to supply high quality silver source to photothermographic material based on silver carboxylate, silver plamitate was prepared by chemical deposition method using palmitic acid, sodium hydroxide, silver nitrate as raw materials and PVP as surfactant in water system. The morphology, crystal structure and thermal properties of silver palmitate were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and Thermogravimetry (TG). The results indicate that silver palmitate has good purity and well-defined layer structure with triclinic phase. The diameter of fiber-like silver palmitate is about 200 nm, which shows excellent dispersion properties. DSC curves demonstrate that silver palmitate has seven endothermic peaks below 240°C. Five endothermic peaks below 190°C assign to different phase transitions. Silver palmitate decomposed step-by-step at 204.1, 223.6, and 253.9°C.