bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Novel Approach to the Synthesis of Endohedral Fullerenes as Demonstrated by Endohedral Barium Fullerenes
Authors: Möschel Christian , Jansen Martin 
Published: July 2007

AbstractA new route to endohedral fullerenes involving the evaporation of carbon and a metal at different positions, i.e. at different temperatures, in a radio‐frequency furnace is described. For the first time, endohedral barium fullerenes within the composition range Ba@C74 to Ba@C136 have been produced in high yields as compared to hollow fullerenes, and have been extracted with CS2. Ba@C60, and Ba@C70, are only soluble in CS2 following sublimation. Furthermore, the first nonlanthanoid dimetallo fullerenes ranging in composition from Ba2@C88 to Ba2@C116 have been obtained. All endohedral barium fullerenes were characterized by mass spectrometry. Properties such as sublimation behaviour, solubility, and sensitivity to air have been studied.
A Novel Stoichiometry for Chlorogold(I) Complexes: Structure of L4Au3Cl3(L =pyrrolidine)
Authors: Jones Peter G. , Ahrens Birte 
Published: July 2007

AbstractThe reaction between (tht)AuCl (tht = tetrahydrothiophene) and neat pyrrolidine (L) leads to the compound L4Au3Cl3. An X‐ray structure determination reveals the presence of molecules LAuCl and ions L2Au+ and Cl−, in the ratio 2:1:1. The packing is characterised by Au.Au contacts and N‐H‐Cl‐hydrogen bonds.
Process Parametric Study for Ethene Carboxylic Acid Removal onto Powder Activated Carbon using Box‐Behnken Design
Authors: Kumar A. , Prasad B. , Mishra I. M. 
Published: July 2007

AbstractEthene carboxylic acid removal from wastewater using powder activated carbon (PAC) requires a proper process parametric study to determine its optimal performance characteristics. Response Surface Methodology (RSM) is one of the advanced statistical analysis techniques for parametric studies involving a minimum number of trials. The Box‐Behnken surface statistical design of experiments was carried out with three factors, i.e., dose, w, temperature, T, and time of contact, t, between the ethene carboxylic acid and the adsorbent, while maintaining the ethene carboxylic acid concentration, C0 = 100 mg/L, as a fixed input parameter. The performance of the Box‐Behnken design was analyzed and optimized using Design‐Expert software for ethene carboxylic acid removal onto adsorbent using a batch system. The higher values of the correlation coefficients, lack‐of‐fit greater than 4 and p values < 0.05 are in good agreement with the optimum combination of process parameters, which proves the fitness of the selected model for analyzing the experimental data.
Application of AIM Parameters at Ring Critical Points for Estimation of π‐Electron Delocalization in Six‐Membered Aromatic and Quasi‐Aromatic Rings
Authors: Palusiak Marcin , Krygowski Tadeusz M. 
Published: July 2007

AbstractThe AIM parameters at thering critical point(the electron density and its Laplacian, the total electron energy density and both its components, potential and kinetic electron energy densities), have been intercorrelated with aromaticity indices: the geometry‐based HOMA and the magnetism‐based NICS, NICS(1), and NICS(1)zz. A set of 33 phenylic rings having possibly a diversified aromatic character, and a set of 20 quasi‐rings formed by intramolecular hydrogen and lithium bonds, have been taken into consideration. It has been found that the density of total electron energy,H, may serve as a new quantitative characteristic of π‐electron delocalization. The dependences betweenHvalues and aromaticity indices are correlated (ccH/HOMA=0.99, ccH/NICS(1)zz=0.95).
Efficacy and safety of imatinib in patients with chronic myeloid leukemia and complete or near‐complete cytogenetic response to interferon‐α
Authors: Branford Susan , Hughes Timothy , Milner Alvin , Koelmeyer Rachel , Schwarer Anthony , Arthur Chris , Filshie Robin , Moreton Susan , Lynch Kevin , Taylor Kerry 
Published: July 2007

AbstractBACKGROUND.Interferon‐alpha (IFN‐α) confers a survival advantage for the minority of patients with chronic myeloid leukemia (CML) who achieve a complete cytogenetic response. The question of whether IFN‐α‐responsive patients can experience further improvements with imatinib has not been answered. Imatinib offers clear quality of life advantages. Furthermore, patients who achieve a major molecular response (MMR) while receiving imatinib are likely to remain progression free.METHODS.A total of 23 patients treated for a median of 4.5 years with IFN‐α (range, 1.6–14.3 years) who had achieved a complete (Philadelphia chromosome [Ph] negative, n = 15 patients) or near‐complete (1–10% Ph, n = 8 patients) cytogenetic response were studied. The primary objective was to determine whether ceasing therapy with IFN‐α and switching to 12 months of imatinib treatment at a dose of 400 mg/day could improve the molecular response as assessed by real‐time quantitative polymerase chain reaction of BCR‐ABL transcript levels. Safety was also assessed.RESULTS.Every patient who had not achieved an MMR while receiving IFN‐α (n = 16 patients) achieved an MMR after a median of 3 months of imatinib treatment. Significant BCR‐ABL reductions (median, 63‐fold; range, 18–425‐fold) occurred in 15 of these patients. Every patient who had already achieved an MMR while receiving IFN‐α (n = 7 patients) maintained an MMR while receiving imatinib. No patients discontinued imatinib due to toxicity, but 1 patient withdrew consent.CONCLUSIONS.These data suggest that switching IFN‐α‐responsive patients to imatinib leads to a rapid improvement in achieving an MMR, a response with established prognostic value, and is well tolerated. The study should help patients and their physicians make evidence‐based decisions regarding the potential benefits and risks of switching to imatinib. Cancer 2007. © 2007 American Cancer Society.
Cost effectiveness of mammography screening for Chinese women
Authors: Wong Irene O. L. , Kuntz Karen M. , Cowling Benjamin J. , Lam Cindy L. K. , Leung Gabriel M. 
Published: July 2007

AbstractBACKGROUND.Although the cost effectiveness of screening mammography in most western developed populations has been accepted, it may not apply to Chinese women, who have a much lower breast cancer incidence. The authors estimated the cost effectiveness of biennial mammography in Hong Kong Chinese women to inform evidence‐based screening policies.METHODS.For the current study, a state‐transition Markov model was developed to simulate mammography screening, breast cancer diagnosis, and treatment in a hypothetical cohort of Chinese women. The benefit of mammography was modeled by assuming a stage shift, in which cancers in screened women were more likely to be diagnosed at an earlier disease stage. The authors compared costs, quality‐adjusted life years (QALYs) saved, and life years saved (LYS) for 5 screening strategies.RESULTS.Biennial screening resulted in a gain in life expectancy ranging from 4.3 days to 9.4 days compared with no screening at an incremental cost of from US$1166 to US$2425 per woman. The least costly, nondominated screening option was screening from ages 40 years to 69 years, with an incremental cost‐effectiveness ratio (ICER) of US$61,600 per QALY saved or US$64,400 per LYS compared with no screening. In probabilistic sensitivity analyses, the probability of the ICER being below a threshold of US$50,000 per QALY (LYS) was 15.3% (14.6%).CONCLUSIONS.The current results suggested that mammography for Hong Kong Chinese women currently may not be cost effective based on the arbitrary threshold of US$50,000 per QALY. However, clinicians must remain vigilant and periodically should revisit the question of population screening: Disease rates in China have been increasing because of westernization and socioeconomic development. Cancer 2007. © 2007 American Cancer Society.
Serum Aspergillus galactomannan antigen values strongly correlate with outcome of invasive aspergillosis
Authors: Woods Gail , Miceli Marisa H. , Grazziutti Monica L. , Zhao Weizhi , Barlogie Bart , Anaissie Elias 
Published: July 2007

AbstractBACKGROUND.Determining the outcome of patients with aspergillosis can be particularly difficult because patients with aspergillosis are at risk for other conditions that mimic this infection. Galactomannan is an Aspergillus‐specific antigen released during invasive aspergillosis and is detected by the quantitative serum galactomannan index (GMI) test.METHODS.Using a kappa correlation coefficient test (KCC), the strength of correlation was determined between GMI and survival outcome of aspergillosis among 56 adults with hematologic cancer (90% had myeloma) who underwent serial GMI monitoring until hospital discharge or death.RESULTS.All 56 patients received antineoplastic therapy (myeloablative followed by stem cell transplantation [autologous in 21 patients and allogeneic in 3 patients] or nonmyeloablative therapy [32 patients]). The overall correlation between survival outcome and GMI was excellent (KCC = 0.8609; 95% confidence interval [95% CI], 0.7093–1.000 [P < .0001]) and was comparable among neutropenic and nonneutropenic patients (KCC = 0.8271; 95% CI, 0.6407–1.000 [P < .0001] and KCC = 1.0; 95% CI, 1–1 [P = .0083], respectively).CONCLUSIONS.The survival outcome of patients with aspergillosis strongly correlated with serum GMI. These findings have important implications for patient care and clinical trials of mold‐active antifungal agents. Cancer 2007; 110:830–4. © 2007 American Cancer Society.
The stabilization of two‐dimensional non‐symmetric half‐plane recursive filters via the discrete Hilbert transformations
Authors: Reddy C. R. , Sathyanarayana P. , Swamy M. N. S. 
Published: July 2007

AbstractThe discrete Hilbert transform (DHT) relations for 2D semicausal signals have been introduced. an alternative algorithm to stabilize non‐symmetric half‐plane (NSHP) recursive filters by applying the DHT directly in the nonsymmetric half‐plane is presented. the results of the direct DHT (DDHT) stabilization procedure are compared with the method of quarter‐plane DHT (QDHT) stabilization after transforming the NSHP polynomial into the quarter‐plane by application of an appropriate transformation. It is observed that the proposed scheme produces the same stable NSHP filter as that obtained through the QDHT method.
Method of analysis of non‐linear systems on the basis of generalization of the volterra functional series relative to complex envelopes
Authors: Kabanov D. A. , Zaytsev A. N. 
Published: July 2007

AbstractThe paper considers the mathematical modelling of weakly non‐linear narrow‐band circuits and systems on the basis of application of the Volterra functional series. the investigation uses multidimensional pulse and transfer functions as well as the Volterra functional series relative to the narrow‐band signal envelopes. Examples are given of the construction of Volterra kernels of narrow‐band non‐linear circuits and systems.
A Mixed‐Mode Analogue and Switch Level Simulator
Authors: Menzel S. P. , Vlach J. 
Published: July 2007

AbstractThis paper describes an experimental mixed‐mode simulation system which couples an incremental time analogue simulator to an event‐driven switch level simulator. the analogue timing programme uses a variable‐step‐size, multi‐order (VSMO) numerical integration algorithm which detects and uses latency while maintaining wave‐form synchronization. the switch level programme uses piecewise linear wave‐forms rather than discrete states to model the operation of logical networks. A unified format in which time responses are events is used for communication between the two programmes. the mixed‐mode simulator operates without backtracking or translation between logical states and analogue wave‐forms.
A general theory for broad‐band matching of two‐ports with applications to fet amplifiers with internal feedback
Authors: Carlin Herbert J. , Civalleri Pier Paolo 
Published: July 2007

AbstractWe prove that the problem of broad‐band matching an arbitrary linear two‐port to resistive terminations by means of input and output lossless equalizers can be reduced to two passive load single‐matching problems by weighting partial gains due to each equalizer with suitable frequency functions.We apply the technique to the problem of determining the maximum of an ideal rectangular gain function for an FET amplifier with internal feedback and losses. the solution is exact for zero feedback. For finite feedback the ideal input‐equalized gain is exact whereas the output least upper bound is approximate. the results in effect provide a figure of merit for a given FET which is a useful yardstick against which practical designs can be evaluated. Some numerical results are presented.
A chebyshev rational function with low Q‐factors
Authors: Rabrenović D. , Lutovac M. 
Published: July 2007

AbstractThe presented rational function is a modification of a recently published Chebyshev rational function defined by means of some orthogonal polynomials. the necessary conditions providing for the lowest pole Q‐factors for a given ripple are found. the function is a ratio of two similar Chebyshev polynomial transfer functions with multiple poles.The selectivity of the function can be increased by using the Chebyshev rational characteristic function instead of the characteristic polynomials. the minimum number of active elements in the cascade connection is obtained with third‐order elliptic characteristic functions.The function is compared with the Cauer (elliptic) and MCPER filters. the distinctive features of the presented function are small Q‐factors of the poles, almost ideal dynamic range, simple design and poles with the same multiplicity m, where m designates the number of cascaded blocks.
Development of a new stabilized four‐phase oscillator based on partial conservativity
Authors: Kaplan B. Z. , Yardeni D. 
Published: July 2007

AbstractThe paper treats the development of a non‐linearly stabilized oscillator model for generating four sine waves in quadrature. the treatment appears important although quadrature signals can also be generated by a well‐known twophase oscillator. the latter generates only two of the signals needed in a four‐phase system, but the rest of the phases signals could nevertheless be generated by simply inverting the two existing signals. For certain applications, however, the generation of all four signals in a completely cyclic and symmetrical manner is preferable. This method of generation is dealt with in the present paper. A previous paper of ours has treated a system of a similar objective. the present system, however, is much simpler. This simplicity is manifested not only through the mathematical representation but also when an electronic realization of the system is considered. the present model realization appears considerably less expensive, since the number of necessarily non‐linear operations is much reduced. This reduction is due to the fact that the non‐linearly stabilized model imbeds a ‘partially conservative’ linear oscillator. the concept of ‘partial conservativity’ has been introduced recently. the present work treats comprehensively the advantages that are gained by imbedding a partially conservative oscillator.
Low‐sensitivity SC realization of brune and C‐type reactance sections
Authors: Fahmy M. F. , El‐Wardaney A. , Raheem G. A. , Fattah F. A. 
Published: July 2007

AbstractThe SC implementation of doubly terminated reactance reference filters containing Brune or C‐type sections is presented. It is shown that the one‐to‐one correspondence between the elements of the reactance reference network and its simulated SC circuit is still maintained. Computer evaluations as well as experimental verifications have shown that the resulting structure is less sensitive with respect to parasitics. Illustrative examples are given.
Extension of a driving‐point and a transfer function to a positive real two‐port matrix
Authors: Martens G. O. , Unbehauen R. 
Published: July 2007

AbstractA solution is presented to the problem, which arises in two‐port modelling, of determining a second driving‐point function from a given driving‐point function and a transfer function. the given functions must have a common denominator and satisfy the necessary positive real (PR) matrix conditions: the driving‐point function must be PR and on the imaginary axis the real part of the transfer function must be zero whenever the real part of the driving‐point function is zero. By using a partial fraction expansion and determining a required first‐order polynomial, a unique second (minimum) driving‐point function is obtained. Examples to illustrate the method are worked out.
Circuit macromodels and large‐signal behaviour of fet‐input operational amplifiers
Authors: Golzio D. , Graffi S. , V.‐Kovács Zs. M. , Masetti G. 
Published: July 2007

AbstractThe origin of the slew rate asymmetry found experimentally in FET‐input LF355 op amps is analysed in order to explain why macromodels based on a strict build‐up technique can fail when used to simulate the behaviour of amplifiers driven by out‐of‐band large voltage signals. These simulations may be very important in predicting the effects of electromagnetic interferences conveyed to the circuit input port. Other performances of op amp macromodels designed either by build‐up techniques or by simplification/build‐up techniques are also compared and discussed.
Relaxation‐based computation of a synchronous sequential circuit stable state
Authors: Diouf Magatte , Carlin Charles‐Henri 
Published: July 2007

AbstractTo perform a mixed mode analysis with the electrical and gate levels in the waveform relaxation context, an initial steady state of the analysed circuit must be computed prior to transient analysis. By using Boolean algebra and discrete relaxation, we propose various algorithms to compute a stable state or a stable total state of a logic synchronous sequential system with master‐slave flip‐flops. Furthermore, a dynamic ordering of the logic gates which improves the convergence of the computation of a stable total state is presented. We show that a stable state can be calculated within only two iterations.
SMOS: A CAD‐compatible statistical model for analogue mos integrated circuit simulation
Authors: Michael Christopher , Abel Christopher , Ismail Mohammed 
Published: July 2007

AbstractAn analogue CAD tool capable of simulating MOS circuit performance variance caused by intra‐die variability inherent to IC fabrication processes has been developed. the nucleus of this tool is a general, CAD‐compatible, MOS statistical model called SMOS which comprehends the effects of device geometry, circuit layout and transistor bias on parameter variance. an example of the model calculation procedure is presented to illustrate both the modelling algorithms and the process characterization data required by the statistical model. the statistical model is verified through experimental data which show excellent agreement with performance variances predicted by simulation. Implementations of the statistical model in two circuit simulation environments, SPICE and APLAC, are also described. Statistical analysis and simulation of two basic analogue subcircuits, the current mirror and the source‐coupled pair, are presented.
Cellular neural networks with non‐linear and delay‐type template elements and non‐uniform grids
Authors: Roska Tamás , Chua Leon O. 
Published: July 2007

AbstractThe cellular neural network (CNN) paradigm is a powerful framework for analogue non‐linear processing arrays placed on a regular grid. In this paper we extend the current repertoire of CNN cloning template elements (atoms) by introducing additional non‐linear and delay‐type characteristics. In addition, architectures with non‐uniform processors and neighbourhoods (grid sizes) are introduced. With this generalization, several well‐known and powerful analogue array‐computing structures can be interpreted as special cases of the CNN. Moreover, we show that the CNN with these generalized cloning templates has a general programmable circuit structure (a prototype machine) with analogue macros and algorithms. the relations with the cellular automaton (CA) and the systolic array (SA) are analysed. Finally, some robust stability results and the state space structure of the dynamics are presented.
A path‐following method for finding multiple equilibrium points in cellular neural networks
Authors: Vandenberghe Lieven , Vandewalle Joos 
Published: July 2007

AbstractOwing to the piecewise linear character of the non‐linearities, the computation of equilibrium points in a cellular neural network could be accomplished in a trivial way by solving 3nlinear systems (wherenis the number of neurons). This is clearly infeasible even for moderatenand it is the purpose of this paper to present a more efficient path‐following method for computing equilibrium points. the method is guaranteed to find at least one solution. the possibility of finding all solutions is also investigated and this leads to new theoretical insight to the relation between the properties of the interconnection matrix and the number of equilibrium points.
Neural networks for constrained optimization problems
Authors: Lillo Walter E. , Hui Stefen , Żak Stanislaw H. 
Published: July 2007

AbstractThis paper is concerned with utilizing neural networks and analogue circuits to solve constrained optimization problems. We propose a novel neural network architecture for solving a class of non‐linear programming problems. the proposed neural network is then used, and if necessary modified, to solve minimum norm problems subject to linear constraints. Minimum norm problems have many applications in various areas, but we focus on their applications to the control of discrete dynamic processes. the applicability of the proposed neural network is demonstrated on numerical examples.
A class of non‐canonic, driving‐point immittance realizations of passive, common‐ground, transformerless, two‐element‐kind RLC networks
Authors: Kandic Dragan , Reljin Branimir 
Published: July 2007

AbstractA new class of non‐canonic, driving‐point immittance realizations of passive, common‐ground, transformerless, two‐element‐kind RLC networks with minimum number of nodes is presented. Six new algorithms of realization are developed by application of canonic, orthogonal matrix transformations with reduced number of degrees of freedom. the number of applied RLC elements of one kind can be minimized and of the other kind reduced, while their parameter values are calculated directly in a linear way.
Simple yet accurate current copiers for low‐voltage current‐mode signal‐processing applications
Authors: Huang Renyuan , Wey Chin‐Long 
Published: July 2007

AbstractAs pressures increase on VLSI designers to use a lower supply voltage of 3.3 V rather than the present 5 V, currentmode signal‐processing techniques will surely become increasingly important and attractive. Numerous current copiers have been proposed. Among them, the copier with a negative feedback approach is the best candidate for low‐voltage current‐mode signal‐processing applications. However, the copier using a positive‐gain feedback amplifier achieves better accuracy at the cost of increasing circuit complexity and settling time. This paper presents an alternative circuit implementation of the negative feedback approach. the proposed current copier uses a negative‐gain feedback amplifier which can be easily realized by a simple circuitry with high accuracy and faster settling time. Simulation results show that with the simple digital CMOS process the proposed copier can be realized with only three transistors, achieves a dynamic range from 300 to 550 μA with an accuracy of 0.1% and can be settled within 3 ns with a power supply of 3.3 V. Thus the copier is well suited to our low‐voltage current‐mode sensor array applications.