bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chronic expression of RET/PTC 3 enhances basal and insulin‐stimulated PI3 kinase/AKT signaling and increases IRS‐2 expression in FRTL‐5 thyroid cells
Authors: Miyagi Eri , Braga‐Basaria Milena , Hardy Elena , Vasko Vasily , Burman Kenneth D. , Jhiang Sissy , Saji Motoyasu , Ringel Matthew D. 
Published: July 2004

AbstractThe RET/PTC3 oncogene is a genetically rearranged and constitutively activated tyrosine kinase receptor that is common in papillary thyroid cancer. Because RET/PTC3 is chronically overexpressed in these thyroid cancer cells, and RET/PTC3‐expressing tumors are associated with overactivity of tyrosine kinase signaling pathways and a more aggressive clinical course, we questioned whether chronic RET/PTC3 expression enhances cellular responses to thyroid mitogens in vitro. We stably transfected FRTL‐5 cells with the RET/PTC3 gene; transfected and control cell lines were cultured without insulin, TSH, or serum. Thymidine incorporation into DNA was enhanced in the RET/PTC3 cells, but transformation was not observed. RET/PTC3 cells demonstrated higher basal and insulin‐stimulated levels of activated Akt, both of which were reduced by LY294002, a PI3 kinase inhibitor, but not PD98059, a MEK inhibitor. By contrast, mitogen activated protein kinase (MAP kinase) was only minimally activated in RET/PTC3 cells before and after stimulation. Consistent with preferential activation of PI3 kinase, increased levels of total and phosphorylated IRS2 protein, relative activation of PDK‐1, and enhanced IRS2‐p85 interactions were identified in RET/PTC3‐expressing cells. RET/PTC3 cells were also sensitized to insulin‐induced thymidine incorporation; this effect was blocked by PI3 kinase (LY294002) rather than MEK 1/2 (PD98059) inhibitors. In summary, we have demonstrated that RET/PTC3 expression enhances basal and insulin‐stimulated DNA synthesis through PI3 kinase, cooperatively activates Akt with insulin via PI3 kinase, and preferentially activates the Akt rather than MAP kinase pathway in FRTL‐5 cells. © 2004 Wiley‐Liss, Inc.
Brain and cancer: The protective role of erythropoietin
Authors: Buemi Michele , Caccamo Chiara , Nostro Lorena , Cavallaro Emanuela , Floccari Fulvio , Grasso Giovanni 
Published: July 2004

AbstractErythropoietin (Epo) is a pleiotropic agent, that is to say, it can act on several cell types in different ways. An independent system Epo/Epo receptor (EpoR) was detected in brain, leading to the hypothesis that this hormone could be involved in cerebral functions. Epo/EpoR expression changes during ontogenesis, thus indicating the importance of this system in neurodevelopment. Moreover, the hypoxia‐induced production of Epo in the adult brain suggests that it could exert a neurotrophic and neuroprotective effect in case of brain injury. Epo could also influence neurotransmission, inducing neurotransmitters (NT) release. Epo therapy in anemic cancer patients is still a controversial issue, because of its possible action as a growth and an angiogenic factor. In our speculative hypothesis Epo could be involved in a “two steps process” that, after a neovascularization phase, leads to its down regulation. Moreover, Epo‐activated signaling pathways could be modulated as possible targets to interfere in neoplastic cells cycle. In conclusion, treatment with rHuEpo could change therapeutical perspectives in different pathological conditions, such as central nervous system (CNS) diseases, but further studies are needed to clarify its physiopathological activities in different clinical fields. © 2004 Wiley Periodicals, Inc.
Stability for the beam equation with memory in non‐cylindrical domains
Authors: Ferreira J. , Santos M. L. , Matos M. P. 
Published: July 2004

AbstractIn this paper, we prove the exponential decay as time goes to infinity of regular solutions of the problem for the beam equation with memory and weak damping

where ${\hat{Q}}$ is a non‐cylindrical domains of ℝn+1 (n⩾1) with the lateral boundary ${\hat{\sum}}$ and α is a positive constant. Copyright © 2004 John Wiley & Sons, Ltd.
Pointwise stabilization of strings with non‐linear feedback
Authors: Berrahmoune Larbi 
Published: July 2004

AbstractWe consider an initial and boundary value problem for a homogenous string subject to an internal pointwise control. The solution resulting from a non‐linear feedback is studied. We give various explicit decay estimates depending on the control position and the feedback non‐linearity. Copyright © 2004 John Wiley & Sons, Ltd.
A sharp interface model for phase transitions in crystals with linear elasticity
Authors: Blesgen T. , Weikard U. 
Published: July 2004

AbstractA model describing phase transitions coupled with diffusion and linear elasticity in crystals under isothermal conditions is introduced. The elastic deformation as well as the phase parameter are obtained directly by the minimization of the free energy. After stating the model, the existence of strong solutions is proved. Copyright © 2004 John Wiley & Sons, Ltd.
Optical clock recovery from 10‐Gb/s NRZ signal
Authors: Betti S. , Bulli C. , Curti F. , Duca E. , Persia S. , Reale A. , Tosi‐Beleffi G. M. 
Published: July 2004

AbstractAll optical clock recovery has been experimentally demonstrated by an actively mode‐locked fiber ring based on the semiconductor optical amplifier (SOA) from a 10‐Gb/s NRZ data stream. The system exploits the cross‐gain modulation (XGM) nonlinear effect in SOA, and a Fabry–Perot etalon suitably inserted in the loop improves the mode‐locking stabilization and efficiency. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 435–437, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20328
Compact copper microstrip filters with spiral resonators
Authors: Huang Frederick , Yue Libin , Gulati Deepika 
Published: July 2004

AbstractCopper microstrip filters using spiral resonators, with a centre frequency of about 1 GHz and bandwidths of 5% and 16%, are designed and tested. Their advantages over parallel‐coupled filters are smaller size and more convenient shape. The spirals alleviate deterioration in simulation accuracy, over‐etch tolerance, and losses due to the size reduction. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 460–463, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20336
Bandwidth enhancement of a microstrip antenna using negative inductance as impedance matching device
Authors: Kaya Adnan , Kılınç Selçuk , Yuksel E. Yesim , Cam Ugur 
Published: July 2004

AbstractIn this study, a novel technique for bandwidth enhancement of a microstrip antenna with a floating negative inductor matching network is presented. A compensation network consisting of three gallium‐arsenide field effect transistors is employed at the input of a microstrip antenna operating at 10 GHz. The performance parameters of the designed microstrip antenna with and without compensation network are compared. The simulation results show that compensation network can improve the bandwidth from 17.21% to 32.67%. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 476–478, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20342
Pulse alignment in an optical‐transmission system
Authors: Cheng D. 
Published: July 2004

AbstractA pair of modulators is used to generate a return‐to‐zero (RZ) optical‐data stream. Dither signals and a microwave power‐detection module are used for error‐signal generation and detection, respectively. The relation between error signal and pulse misalignment is explicitly given. Prototypes are built to validate the design concept of the high‐speed pulse‐alignment control loop. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 478–483, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20343
Accurate charge‐control model for analysis of noise properties for AlGaAs/GaAs hemt and AlGaAs/InGaAs phemt at microwave frequencies
Authors: Guru Vandana , Vyas H. P. , Gupta Mridula , Gupta R. S. 
Published: July 2004

AbstractAn accurate charge‐control approach to analytical noise modeling of a high electron mobility transistor, which provides excellent results in agreement with the experimental data, is presented. The small‐signal parameters, and the drain and gate‐noise sources are calculated to determine the noise coefficients, minimum noise figure Fmin and minimum noise temperature Tmin. The influence of drain current, frequency, and device parameters upon Fmin and Tmin for AlGaAs/GaAs HEMT and AlGaAs/InGaAs/GaAs PHEMT is presented. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 489–494, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20346
Parametric amplifier for mid‐span phase conjugation with simultaneous compensation of fiber loss and chromatic dispersion at 10 Gb/s
Authors: Boggio J. M. Chávez , Guimarães A. , Callegari F. A. , Marconi J. D. , Rocha M. L. , deBarros M. R. X. , Fragnito H. L. 
Published: July 2004

AbstractWe demonstrate simultaneous compensation of loss and chromatic dispersion for 10‐Gb/s transmission over 90‐km of standard fiber using mid‐span phase conjugation with a fiber‐optic parametric amplifier that provides 9.4‐dB gain over a bandwidth of 17 nm. The observed power penalty is less than 1.5 dB (at BER < 10−9) relative to back‐to‐back measurements. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 503–505, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20350
Comparison of preoperative and postoperative pressure transmission ratio and urethral pressure profilometry in patients with successful outcome following the vaginal wall patch sling technique
Authors: Mikhail Magdy S. , Rosa Hector , Palan Prabhudas , Anderson Patrick 
Published: July 2004

AbstractAimsWe studied preoperative and postoperative pressure transmission ratio (PTR) and urethral pressure profilometry in patients undergoing the vaginal wall patch sling technique as a first surgical approach for genuine stress incontinence (GSI) with urethral hypermobility. The specific aims were to determine the exact urodynamic parameters, if any, that may be improved postoperatively and to report the urodynamic outcome of the vaginal wall patch sling technique in successful cases.MethodsPreoperatively, all patients had a positive standing stress test, urethral hypermobility on Q‐tip testing, and normal postvoid residual volume. On urodynamics, all patients had equalization of maximum urethral closure pressure (MUCP) on cough profilometry, and absence of detrusor contractions on subtracted cystometry. The PTR for each cough was calculated. Cough spikes were assigned locations in the first, second, third, or fourth quartile of the functional urethral length (FUL). Urethral pressure profilometry was performed at bladder capacity in the sitting position. All urodynamic tests were repeated 3–6 months postoperatively. A two‐tailed t‐test was used for statistical analysis.ResultsForty‐eight patients demonstrated successful outcome at initial follow up and constituted the study population. There was a statistically significant increase in MUCP at stress as well as a statistical increase in PTR in the first, second, and third quartiles of the FUL postoperatively.ConclusionsThe vaginal patch sling technique appears to restore continence both by buttressing the urethra at times of stress as well as repositioning the proximal urethra into the intra‐abdominal pressure zone, thus, enhancing pressure transmission to the proximal urethra. © 2004 Wiley‐Liss, Inc.
Histochemical and contractile properties of striated muscles of urethra and levator ani of dogs and sheep
Authors: Chen Xinmin , Creed Kate E. 
Published: July 2004

AbstractAimsTo understand their possible importance in long‐ and short‐term control of continence, some properties of the striated muscles of the urethra and pelvic floor (levator ani) of dogs and sheep were investigated, especially fiber types and contractile characteristics.Materials and MethodsStriated muscles of urethra and levator ani of 29 male and 6 female dogs and 11 male and 6 female sheep were removed and cut into strips. Some strips were frozen and stained for ATPase at pH 9.4 and 4.3 for fiber typing; others were set up in an organ bath to study contractile responses to nerve stimulation.ResultsAll muscles contained both type I (slow) and type II fibers, ranging from 97% type II in female greyhound urethra to 60% in female sheep levator ani. For each muscle, there were fewer type II muscles in sheep than in dog. The diameters of the urethral fibers were about 60% of the levator ani in dogs and 34% in sheep. Contraction of the urethral muscle was faster than for levator ani and declined to about 80% of the peak, 500 msec after the beginning of stimulation at 20 Hz. The levator ani contraction rose to a steady level as long as stimulation continued.ConclusionsBoth the levator ani and urethral striated muscles contain slow and fast fiber types. The levator ani muscles are capable of sustained contraction with rapid onset which will produce long‐term closure of the urethra. The circular urethral muscle contraction was faster but less well maintained. © 2004 Wiley‐Liss, Inc.
Enhanced lymphocyte proliferation responses in pediatric patients early after myelosuppressive chemotherapy
Authors: Stachel Daniel , Fütterer Agnes , Haas Rainer J. , Schmid Irene 
Published: July 2004

AbstractBackgroundIt has long been known that patients both after myelosuppressive chemotherapy (ChTh) and after myeloablative bone marrow transplantation (BMT) show a long lasting impairment of cellular immune functions. However, recent reports have revealed that early after BMT a passing state of augmented immune responsiveness exists. Adoptive T cell therapy in this period of lymphopenia‐induced (homeostatic) proliferation has shown better results than in steady state in murine studies.ProcedureTo determine whether also early after myelosuppressive ChTh enhanced immune responses can be found, we have determined proliferation of peripheral blood lymphocytes and calcium influx and performed immunophenotyping in pediatric patients recovering from myelosuppressive ChTh in comparison to immunoreconstituted patients late after BMT.ResultsThe lymphocytes of the ChTh patients were found to proliferate vigorously in response to stimulation with a variety of antibodies and mitogens, while in the BMT patients any stimulation was severely reduced. The increase of intracellular calcium after stimulation was similar in both patient groups. ChTh patients showed an expansion of an activated “naïve” phenotype (CD45RO− HLA‐DR+) in both the CD4 and CD8 subsets. In contrast, BMT patients showed a prominent expansion of “memory type” T lymphocytes (CD45RO+ HLA‐DR+).ConclusionsEarly after ChTh, a period of immunoaugmentation seems to exist. Whether this observation can be used clinically to increase cure rates remains to be elucidated. © 2004 Wiley‐Liss, Inc.
Expanding the supramolecular polymer LEGO system: Nitroxide‐mediated living free‐radical polymerization as a tool for mono‐ and telechelic polystyrenes
Authors: Lohmeijer Bas G. G. , Schubert Ulrich S. 
Published: July 2004

AbstractNitroxide‐mediated, controlled living radical polymerization was employed to introduce terpyridine ligands at one or two chain ends of polystyrene. For this purpose, a unimolecular initiator bearing both a terpyridine ligand as well as a mediating nitroxide was synthesized and used for the controlled polymerization of styrene. Moreover, a maleimide‐functionalized terpyridine was prepared in order to synthesize telechelic polymers, utilizing nitroxide substitution reactions. Kinetic studies of the polymerization of styrene were carried out. In all polymerizations, special attention was focused on the retention of end‐group functionality, in light of the effects of autoinitiation and autopolymerization. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4016–4027, 2004
Low dielectric thermoset. IV. Synthesis and properties of a dipentene‐containing cyanate ester and its copolymerization with bisphenol A dicyanate ester
Authors: Lin Ching Hsuan , Hsiao Chu Nan , Li Chun Hung , Wang Chun Shan 
Published: July 2004

AbstractA 2,6‐dimethylphenol‐dipentene dicyanate ester (DPCY) was synthesized from the reaction of 2,6‐dimethylphenol‐dipentene adduct and cyanogen bromide. The proposed structure was confirmed by Fourier transform infrared (FTIR), elemental analysis, mass, and nuclear magnetic resonance (NMR) spectra. DPCY was then cured by itself or cured with bisphenol A dicyanate ester (BADCY). Thermal properties of cured epoxy resins were studied using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), dielectric analysis (DEA), and thermogravimetric analysis (TGA). These data are compared with those of BADCY. The cured DPCY exhibits a lower dielectric constant (2.61 at 1 MHz), dissipation factor (29.3 mU at 1 MHz), thermal stability (5% degradation temperature and char yield are 429 °C and 17.64%, respectively), glass transition temperature (246 °C by TMA and 258 °C by DMA), coefficient of thermal expansion (33.6 ppm before Tg and 134.1 ppm after Tg), and moisture absorption (0.95% at 48 h) than those of BADCY, but higher moduli (5.12 GPa at 150 °C and 4.60 GPa at 150 °C) than those of the bisphenol A system. The properties of cured cocyanate esters lie between cured BADCY and DPCY, except for moduli. Moduli of some cocyanate esters are even higher than those of cured BADCY and DPCY. A positive deviation from the Fox equation was observed for cocyanate esters. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3986–3995, 2004
Tunable block copolymers based on a polysiloxane backbone by anionic ring‐opening polymerization
Authors: Bauer Josef , Hüsing Nicola , Kickelbick Guido 
Published: July 2004

AbstractBlock copolymers with tunable functional groups were obtained through the postfunctionalization of poly(dimethylsiloxane)‐b‐poly(methylvinylsiloxane) diblock copolymers prepared by the anionic ring‐opening polymerization of cyclotrisiloxanes. As the source of the vinyl‐containing segment, 1,3,5‐trimethyl‐1,3,5‐trivinylcyclotrisiloxane was used. The obtained polymers showed high block purity and a narrow molecular weight distribution. The postmodification was carried out with a two‐step procedure: in the first step, epoxide groups were introduced into the diblock copolymer, and in the second step, the ring opening of the latter functionalities was carried out. A variety of different nucleophiles were used for the ring‐opening reaction, and the influence of selected reaction parameters, such as the dilution and the use of monofunctional and difunctional nucleophiles, on the resulting polymers were investigated. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3975–3985, 2004
Synthesis and characterization of new light‐emitting copolymers in polymeric‐light‐emitting‐diode device fabrications
Authors: Wu Sheng‐Han , Shen Chi‐Hsien , Chen Jar‐Hung , Hsu Chia‐Chen , Chien‐Chao Tsiang Raymond 
Published: July 2004

AbstractA series of thiophene‐containing photoactive copolymers consisting of alternating conjugated and nonconjugated segments were synthesized. The 1H NMR spectra corroborated the well‐defined structures, and the copolymers not only were soluble in common organic solvents but also had high glass‐transition temperatures (ca. 130 °C) and good thermal stability up to 390 °C. Introducing aliphatic functional groups, such as alkyl or alkoxyl, into chromophores of the copolymers redshifted the photoluminescence spectra and lowered the optical bandgaps. The electrochemical bandgaps calculated from cyclic voltammetry agreed with the optical bandgaps and thus indicated that electroluminescence and photoluminescence originated from the same excited state. The energy levels (highest occupied molecular orbital and lowest unoccupied molecular orbital) of all the copolymers were lower than those of poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1.4‐phenylenevinylene] MEH–PPV, indicating balanced hole and electron injection, which led to improved performance in both single‐layer and double‐layer polymeric‐light‐emitting‐diode devices fabricated with these copolymers. All the copolymers emitted bluish‐green or green light above the threshold bias of 5.0 V under ambient conditions. At the maximum bias of 10 V, the electroluminescence of a device made of poly(2‐{4‐[2‐(3‐ethoxy phenyl)ethylene]phenyl}‐5‐{4‐[2‐(3‐ethoxy,4‐1,8‐octanedioxy phenyl)ethylene]phenyl}thiophene) was 5836 cd/m2. The external electroluminescence efficiency decreased with the lifetime as the polymer degraded. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3954–3966, 2004
Significance of conformational biases in Monte Carlo simulations of protein folding: Lessons from Metropolis–Hastings approach
Authors: Przytycka Teresa 
Published: July 2004

AbstractDespite significant effort, the problem of predicting a protein's three‐dimensional fold from its amino‐acid sequence remains unsolved. An important strategy involves treating folding as a statistical process, using the Markov chain formalism, implemented as a Metropolis Monte Carlo algorithm. A formal prerequisite of this approach is the condition of detailed balance, the plausible requirement that at equilibrium, the transition from state i to state j is traversed with the same probability as the reverse transition from state j to state i. Surprisingly, some relatively successful methods that use biased sampling fail to satisfy this requirement. Is this compromise merely a convenient heuristic that results in faster convergence? Or, is it instead a cryptic energy term that compensates for an incomplete potential function? I explore this question using Metropolis–Hasting Monte Carlo simulations. Results from these simulations suggest the latter answer is more likely. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Relativistic and electron correlation effects for molecules of heavy elements: Ab initio fully relativistic coupled‐cluster calculations for PbH4
Authors: Malli Gulzari L. , Siegert Martin , Turner David P. 
Published: July 2004

AbstractAb initio fully relativistic all‐electron Dirac–Fock (DF) and nonrelativistic (NR) Hartree–Fock (HF) limit self‐consistent field (SCF) benchmark molecular calculations are reported for the tetrahedral (Td) PbH4 at various Pb–H bond distances. Our fully relativistic Dirac–Fock and nonrelativistic HF calculations predict for a PbH4 bond distance of 1.75 and 1.82 Å, respectively. Both our DF and NR HF limit SCF calculations predict the ground state of PbH4 (Td) to be bound, with the predicted atomization energy (Ae) of 7.20 and 8.63 eV, respectively. There are antibinding effects due to relativity of ∼1.4 eV to the predicted atomization energy (Ae) of PbH4. Our relativistic four‐component coupled‐cluster singles and doubles (RCCSD) calculations, which correlate 50 electrons and include 302 active molecular spinors with energies up to ∼46 a.u. in the active space predict the relativistic second‐order Møller‐Plesset (RMP2), RCCSD and RCCSD (T) (RCCSD plus the triple excitation correction included perturbationally) correlation energies as −1.271, −1.161, and −1.186 hartree, respectively. The contribution of the RMP2, RCCSD, and RCCSD (T) electron correlation energies toward the atomization energy of PbH4 as predicted by our above‐mentioned CC calculation is 3.78, 4.22, and 4.30 eV, respectively. We predict the NR and relativistic MP2, CCSD, and CCSD (T) atomization energies (Ae) for PbH4 at the optimized PbH bond distances as 12.72, 12.90, 1.77 and 10.98, 11.42, and 11.50 eV, respectively. With the inclusion of both the electron correlation and effects of relativity, we predict the atomization energy for PbH4 to be ∼10–11 eV. This should encourage experimentalists to devise new synthetic methods to prepare plumbane, so that its chemical and physical properties can be investigated as in the case of its lighter congeners. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004