bluuebunny/crossref_metadata_2025 huggingface dataset:
Coupling of the Polymer Threading a Membrane Transition to the Membrane Adsorption Transition
Authors: Di Marzio Edmund A. , Guttman Charles M.
Published: August 2005

A polymer molecule threading through a pore in a plane membrane is allowed to adsorb on either or both sides of the membrane. Further, it is confined to the vicinity of the membrane by two plane barriers lying on either side of the membrane. A lattice model of this problem is exactly solvable by matrix techniques. The equilibrium translocation behavior is described as a function of the polymer MW, the membrane adsorption energies, the solution properties, the barrier separations, applied force, and the temperature. The transition is first‐order, meaning that small changes in any of these 9 quantities can in the limit of infinite MW, completely translocate the polymer. The work of Park and Sung who used Smoluchowski‐like equations to calculate translocation transit times can be generalized by use of the sea‐snake model which is relevant to isolated polymer chains in solution. The physics behind the sea‐snake model is that if one monomer is pulled into the membrane, the distance the center of mass of the untranslocated portion of the chain moves is MW−1/2 of the distance between monomer units. This reduces the effective friction coefficient by MW1/2. It is found for the sea‐snake model that the MW dependence of transit times varies as MW3/2 or MW depending on whether we use a free draining or a non‐free draining picture for the polymer.
Toward a Constitutive Law of Cartilage: A Polymer Physics Perspective
Authors: Basser Peter J. , Horkay Ferenc
Published: August 2005

To describe load bearing and lubrication of cartilage requires treating its collagen network and proteoglycan (PG) phases separately in a constitutive law of the tissue. We propose a framework for developing such an empirical constitutive law that treats the cartilage extracellular matrix (ECM) as a composite medium, with a PG phase that exerts a swelling pressure, and a collagen network phase that restrains it. We compare and contrast this model to a biomechanical constitutive law that aggregates the collagen and PG phases into a single “solid‐like” elastic tissue matrix, and show that aggregation obscures essential differences in the physical‐chemical properties of the collagen and PG constituents as well as their distinct biological roles within cartilage's ECM. We also relate moduli in the aggregate constitutive model to quantities measured in an osmotic stress titration experiment.
Manipulation of Polymer Chain Entanglement and Self‐Assembly for DNA Capillary Electrophoresis
Authors: Chu Benjamin , Ying Qicong , Wang Yanmei , Zhang Jun
Published: August 2005

A conceptual model has been developed and tested experimentally on five different aspects, relating to the architecture and topology of the polymers making up the transient network that constitutes the separation matrix. The concept can be applied for DNA sequencing analysis and separations of short fragments double‐stranded DNA as well as oligonucleotides. Examples are provided to illustrate the success of the concept.
Modeling Ca‐Polyanion Crosslinking in Secretory Networks. Assessment of Charge Density and Bond Affinity in Polyanionic Secretory Networks
Authors: Chin Wei‐Chun , Quezada Ivan , Steed Jordan , Verdugo Pedro
Published: August 2005

Materials released by secretory cells are stored inside intracellular membrane‐bound vesicles. These moieties are not freely diffusible in the vesicle but remain immobilized in a Ca2+‐crosslinked condensed‐phase polyanionic polymer matrix. During exocytosis a Na+/Ca2+ ion exchange process triggers a volume phase transition resulting in massive swelling and release of the materials to the extracellular space. Here we formulate a simple model to assess Ca2+‐ion binding from the swelling kinetics of polymer networks. We found the diffusivity of the networks (D) exhibits a power‐law dependency on the Ca2+ concentration where D ∝ [Ca2+]−2/3. The model yields an estimate of charge density and ionic affinity of the polymer chains. Studies of post‐exocytic swelling kinetics in airway mucin granules, mast cell granules and granules from the microalga (Phaeocystis globosa) were used to validate predictions from our model. These results suggest that independent of the cell type, from animal to plant cells, a single polyelectrolyte interaction mechanism appear to be responsible for product release in exocytosis.
Abrupt Structural Changes in Polyanionic Gels Evoked by Na‐Ca Ion Exchange: Their Biological Implications
Authors: Tasaki Ichiji
Published: August 2005

Anionic polyelectrolyte gels, synthetic or natural, undergo abrupt structural changes when the monovalent counterions in the gel, e.g., Na+, are replaced with divalent cations, e.g., Ca2+. These structural changes are caused by the preferential binding of Ca2+ to the polyelectrolyte chains and the ability of Ca2+ to form crosslinks between two neighboring chains. Strong lyotropic (Hofmeister) effects of anions, such as fluoride, phosphate, aspartate and chloride, on the repetitiveness of abrupt structural changes in the gel strands are demonstrated. These findings have important biological implications.
Development of Liquid Crystalline Order During Cure of Mesogenic Epoxy Resins
Authors: Mossety‐Leszczak Beata , Włodarska Magdalena , Galina Henryk , Bąk G.W. , Pakula Tadeusz
Published: August 2005

In the present paper we describe the curing process of a new liquid crystalline epoxy monomer with 4,4′‐diaminodiphenylenemethane (DDM). The characteristic of cured product is presented. Both the monomer and cured product have been characterized by IR and NMR spectroscopy, differential scanning calorimetry (DSC), polarized optical microscopy (POM), wide‐angle X‐ray scattering (WAXS) and dielectric relaxation spectroscopy (DRS).The curing process was analysed with the use of DSC and real‐time DRS.
Chemically and Physically Induced (Reversible) Gelation of Organic Liquids by Monomeric and Polymeric Gelators
Authors: George Mathew , Luo Chuping , Wang Caihua , Carretti Emiliano , Dei Luigi , Weiss Richard G.
Published: August 2005

The properties of several types of organogels that can undergo a chemical transition during gelation or while in the gel phase are described. The transitions can be physically induced by light or chemically triggered by the addition of an acid or a neutral molecule such as CO2 or CS2. In some cases, the gelation properties of the new species formed are markedly different from those of the precursors. The link between molecular structure and the nature of the gel networks as well as results obtained from the multidisciplinary tools used to study them are discussed.
Three‐Dimensional Collagen Gel Networks for Neural Stem Cell‐Based Neural Tissue Engineering
Authors: Ma Wu , Chen Silvia , Fitzgerald Wendy , Maric Dragan , Lin Hsingch J. , O'Shaughnessy Thomas J. , Kelly Jeremy , Liu Xiu‐Huai , Barker Jeffery L.
Published: August 2005

Stem and progenitor cells isolated from the embryonic rat cerebral cortex were immobilized by matrix entrapment in three‐dimensional (3D) Type I collagen gels, and cultured in serum‐free medium containing basic fibroblast growth factor. The cells trapped within the collagen networks actively proliferated and formed clone‐like aggregates. Neurons were the first differentiated cells to appear within the aggregates, followed by generation of astrocytes and oligodendrocytes. In addition, necrotic cores were developed as the aggregate diameter increased and cell viability declined significantly after 3 weeks in culture. To overcome these problems, the cell‐collagen constructs were transferred to Rotary Wall Vessel bioreactors for up to 10 weeks. In the rotary culture, the collagen gels compacted 3‐4 folds and a long‐term growth and differentiation of neural stem and progenitor cells was dynamically maintained. Remarkably, the cell‐collagen constructs formed a complex two‐layered structure that superficially emulated to a certain extent the cerebral cortex of the embryonic brain in architecture and functionality. The engineered 3D tissue‐like constructs displaying characteristic properties of neuronal circuits may have potential use in tissue replacement therapy for injured brain and spinal cord.
Multi‐Material Scaffolds for Tissue Engineering
Authors: Darling Andrew , Shor Lauren , Khalil Saif , Mondrinos Mark , Lelkes Peter , Guceri Selcuk , Sun Wei
Published: August 2005

A trend in developing biocompatible scaffolds for tissue engineering has been to seek an ideal single material for which a given cell type will exhibit favorable behavior. While an ideal single material has proven elusive, scaffold manufacture using combinations of specialist materials can produce more versatile structures. By controlling the percentage and architecture of material components, mechanical properties, cell attachment, and proliferation may be optimized for a given function. Three specialist materials, poly‐ϵ‐caprolactone (PCL), fibrin, and alginate, were incorporated into multi‐component scaffolds for a series of experiments testing each component with culture of fibroblasts. The rigid and formable PCL provided structure, the fibrin pore‐filler allowed for cell attachment, and alginate thread provided a nutrient transfer pathway in lieu of a vascular system. The efficacy of these scaffolds was judged on fibroblast distribution and population after 7‐12 days of culture.
Thermotropic Polymer Gels: Smart Gel Glass
Authors: Szilágyi András , Gyenes Tamás , Filipcsei Genovéva , Zrínyi Miklós
Published: August 2005

Several attempts have been made recently in order to develop “smart” windows, which can moderate light and heat intensities. Thermotropic gels have met with growing interest because of their advanced properties. Based upon phase transitions of polymer gels, a novel thermally adjustable window, which includes a gel layer, has been developed in our laboratory. The so‐called gel‐glass becomes opaque when the temperature exceeds a certain value and goes back to its original transparent state when it is cooled below the critical value again. Intelligent “gel‐glasses” made of these materials can moderate the amount of sunlight and radiated heat. The optical properties of the gel layer are also modified by the Joule heat of audio frequency AC current. Two types of gel‐glasses have been developed and investigated. Phase transition temperature of a poly(N‐isopropylacrylamide) based gel was adjusted by copolymerization and by changing of the solvent composition. The cloud point of a poly(methyl vinyl ether) – water system in a PVA gel was varied by modifying the composition of the swelling agent. In the case of electrically adjustable thermotropic windows, optical properties, energy consumption and temperature changes during the switching process were studied.
Out‐of‐band improvement by BPFs with multiple attenuation poles using a condition of variable coupling length of a parallel partially coupled‐line section
Authors: Pokharel Ramesh K. , Wada Kouji , Ohno T. , Hashimoto Osamu
Published: August 2005

A combination of two microstrip‐line resonators, which are partially coupled, are considered in a parallel partially coupled‐line bandpass filter (BPF), where one resonator is one half‐wavelength (λ/2) long, and the other (whose one end is grounded) is only one quarter‐wavelength (λ/4) long. Therefore, the length of a coupled‐line section can be varied based on the position of the grounded end. Five conditions of the movable coupling length are simulated, which greatly influences the spurious responses of the BPF. This property is numerically investigated in this paper. The analysis shows that, based on the grounding position, this method is capable of realizing improved out‐of‐band characteristics by locating the multiple attenuation poles in the stopband and improved spurious responses up to five times of the passband frequency (5f0) of a parallel partially coupled‐line BPF. An empirical model of the BPF is fabricated, and the numerical results are verified via comparison with the experiment. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 4–9, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21064
Infrared‐frequency coplanar striplines: Design, fabrication, and measurements
Authors: Mandviwala Tasneem , Lail Brian , Boreman Glenn
Published: August 2005

We investigate the feasibility of coplanar striplines (CPSs) in conjunction with infrared (IR) detectors. Because of unique attenuation and dispersion issues, the analytical formulas for transmission‐line parameters valid below a few hundred GHz are not applicable at IR. Therefore, we perform numerical modeling to determine these parameters (at 28.3 THz). A comparison of the modeling and the measured response is presented. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 17–20, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21068
All fiber erbium‐ytterbium co‐doped fiber laser
Authors: Wang Hua , Li Yi‐Gang , Chen Sheng‐Ping , Zhu Jian‐Ping , Zhang Yun , Xu Tuan‐Wei , Lu Ke‐Cheng
Published: August 2005

An all‐fiber erbium‐ytterbium co‐doped fiber laser (EYDFL), with a double‐cladding erbium‐ytterbium co‐doped fiber (EYDF) of 15 m as active fiber, is reported. Up to 1.027‐W output power at 1567.0 nm under pump power of 3.16 W and slope efficiency of 34.5% with respect to the launched pump power are obtained. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 31–34, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21072
Novel compact microstrip bandpass filter using a triangular resonator
Authors: Chen Jian‐Xin , Shi Jin , Xue Quan
Published: August 2005

A novel compact microstrip bandpass filter using a triangular resonator is proposed. The bandpass filter has the characteristic of the quasi‐elliptical response, and several transmission zeros in the stopband are realized in order to improve the selectivity of the passband. A demonstration filter was designed, fabricated, and tested. The theoretical and experimental results are presented. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 49–50, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21078
Evaluation of scattering parameters, gain, and feedback‐capacitance‐dependent noise performance of a pseudomorphic high‐electron‐mobility transistor
Authors: Guru Vandana , Vyas H. P. , Gupta Mridula , Gupta R. S.
Published: August 2005

This paper evaluates microwave performance in terms of scattering parameters and gains and presents the effect of gate‐to‐drain capacitance Cgd on the noise behavior of a pseudomorphic high‐electron mobility transistor (PHEMT). An analytical expression for Cgd is obtained and the influence of gate length, epilayer thickness, and gate and drain bias upon this PHEMT is studied. Analytically calculated small‐signal parameters are used to evaluate the intrinsic and extrinsic scattering parameters and gains of the PHEMT. Finally, the dependence of bias and frequency on minimum noise figure, scattering parameters, and gains is studied. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 51–57, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21079
An essential difference between dielectric mirrors and chiral mirrors
Authors: Lakhtakia Akhlesh , Xu Jian
Published: August 2005

The boundary conditions on the exposed face of a dielectric mirror are shown to be effectively the same as those for perfect electric conductors, whereas the boundary conditions on the exposed face of a chiral mirror are very different from those for either perfect electric conductors or perfect magnetic conductors. Cavities between two chiral mirrors have a relatively uniform field distribution, which is significant for spectral‐hole filters and coherent light generation. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 63–64, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21082
Design tradeoff for SiGe 0.35‐μm BiCMOS low‐power and high figure‐of‐merit LNA
Authors: Chen Hsien‐Ku , Chen Hsien‐Jui , Juang Ying‐Zong , Chiu Chin‐Fong
Published: August 2005

A 5.4‐mW ultra‐low dc power low‐noise amplifier (LNA) at 5.5 GHz, based on 0.35‐μm BiCMOS technology, is presented. The trade‐off between the NF and linearity for LNA circuit design has been investigated. Furthermore, the use of the HBT‐cascade‐MOS methodology simultaneously satisfies the trade‐off between the noise figure (NF) and linearity of the LNA. This amplifier achieves a gain/NF × PDCratio figure of merit of 0.774 (1/mW), which is the best reported at the 5–6‐GHz band, and is suitable for wireless LAN applications. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 65–68, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21083
VCO active integrated antenna with reactive impedance surfaces
Authors: Urbani Fabio , Bilotti Filiberto , Alù Andrea , Vegni Lucio
Published: August 2005

In this paper, we present the design of an active integrated antenna (AIA) using a voltage‐controlled oscillator (VCO) for applications in the Industrial Scientific Medical (ISM) band (2.4 to 2.4835 GHz). The realized active circuit makes use of compact devices in surface‐mounting device (SMD) technology, while the passive radiating element is placed over a reactive‐impedance surface (RIS), properly designed to show an inductive surface impedance within the operative frequency band. The final layout has been optimized in terms of dimensions to achieve the integration of the antenna and the active/transmissive circuits on the opposite faces of a Personal Computer Memory Card International Association (PCMCIA) card. The design is conducted through the employment of a rigorous method of moments (MoM) formulation, used for the design of the antenna, and of a commercial tool for the nonlinear analysis of the active circuitry. Some preliminary experimental results are also presented to illustrate the features of the antenna here proposed. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 82–86, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21088
A 60‐GHz GaAs micromachined slow‐wave bandpass filter using a microstrip stepped‐impedance hairpin resonator
Authors: Cho Ju‐Hyun , Yun Tae‐Soon , Kim Ki‐Byoung , Baek Tae‐Jong , Ko Baek‐Seok , Shin Dong‐Hoon , Lee Jong‐Chul
Published: August 2005

In this paper, a new microstrip stepped‐impedance hairpin resonator (SIHR) slow‐wave bandpass filter (BPF) using a dielectric‐supported air‐gapped microstrip line (DAML) via surface micromachining on GaAs substrate is proposed. The slow‐wave periodic structures utilize the parallel‐ and series‐resonance characteristics of the resonators to construct a band‐pass filter. The proposed slow‐wave band‐pass filter is designed to produce a passband of 10% at the fundamental frequency of 60 GHz. It exhibits insertion loss of 2.23 dB, return loss of better than 15 dB, and a stopband greater than 35 dB. This filter is useful for many millimeter‐wave system applications. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 86–89, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21089
Compact microstrip‐fed antenna with band‐stop characteristic for ultra‐wideband applications
Authors: Choi Wooyoung , Jung Jihak , Chung Kyungho , Choi Jaehoon
Published: August 2005

A novel compact and microstrip‐fed antenna with band‐stop characteristic for ultra‐wideband applications is presented. By embedding a notch in the ground plane, the ultra‐wideband property for the proposed antenna is achieved. To create a frequency band‐stop characteristic, a simple U‐shape slot is inserted into the radiating patch. The designed antenna has a stop‐band of 4.92 to 5.86 GHz while maintaining wideband performance from 3.1 to 11.25 GHz for the return loss of less than −10 dB. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 89–92, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21090
Pulmonary interstitial glycogenosis in identical twins
Authors: Onland W. , Molenaar J.J. , Leguit R.J. , van Nierop J.C. , Noorduyn L.A. , van Rijn R.R. , Geukers V.G.M.
Published: August 2005

We present the clinical, radiological, and pathological findings of open lung biopsies from monozygotic prematurely born male twins with respiratory distress at ages 6 and 8 weeks postnatally. Radiological examination showed a reticular nodular interstititial pattern on chest radiography. High‐resolution computed tomography (HRCT) revealed ground‐glass opacification and thickened interstitial septae in both infants. Lung biopsies showed a similar histology. There was diffuse interstitial thickening of the alveolar septa by mesenchymal cells, without prominent hyperplasia of type 2 pneumocytes, and without airspace exudates. Sections were periodic acid‐Schiff (PAS)‐positive within the cytoplasm of interstitial cells, indicating the presence of glycogen. Thus the diagnosis of pulmonary interstitial glycogenosis was made. Both infants were treated with glucocorticoids and had a favorable outcome. We speculate that pulmonary interstitial glycogenosis could be a histopathological form of chronic lung disease (CLD) of infancy. Pediatr Pulmonol. © 2005 Wiley‐Liss, Inc.
Randomized, placebo‐controlled trial of albuterol and epinephrine at equipotent beta‐2 agonist doses in acute bronchiolitis
Authors: Ralston Shawn , Hartenberger Carol , Anaya Theresa , Qualls Clifford , Kelly H. William
Published: August 2005

Our objective was to determine if nebulized racemic epinephrine is more efficacious than nebulized albuterol or saline placebo in the treatment of bronchiolitis in the outpatient setting when dosing is equivalent in terms of beta‐2 agonist potency. Sixty‐five patients between ages 6 weeks and 24 months with a diagnosis of bronchiolitis, defined as first‐time wheezing, upper respiratory symptoms and/or fever, and a Respiratory Distress Assessment Instrument score of at least 4, were randomized to receive 5 mg nebulized albuterol, 5 mg nebulized racemic epinephrine, or an equivalent volume of placebo at 0, 30, and 60 min. The primary outcome measure was need for hospital admission or home oxygen. Secondary outcome measures were changes in clinical scores and oxygen saturations. There were no significant statistical differences between groups in terms of need for hospital admission or outpatient management with home oxygen therapy. There were no differences between groups in terms of changes in clinical scores or oxygen saturations. Racemic epinephrine and albuterol at equivalent doses had no effect on the need for hospitalization or supplemental oxygen in bronchiolitis in the outpatient setting compared to nebulized saline placebo, though this study may have missed less dramatic clinical effects due to small sample size. Pediatr Pulmonol. © 2005 Wiley‐Liss, Inc.
Childhood diffuse panbronchiolitis: A case report
Authors: Aslan Ayse Tana , Ozcelik Ugur , Talim Beril , Haliloglu Mithat , Dogru Deniz , Dalgıc Fuheda , Kiper Nural
Published: August 2005

Diffuse panbronchiolitis (DPB) is a chronic, potentially life‐threatening lower respiratory tract disease that is particulary common in Japanese people. If left untreated, it progresses to bronchiectasis, respiratory failure, and death. Lack of familiarity with DPB in the non‐Far East may result in a failure to correctly diagnose and treat this disorder. We describe a child with DPB. We suggest that DPB is a sinopulmonary disease that is not exclusive to the Asian population and to adults. Its clinical and radiological features should be better known by pediatric pulmonary physicians. Pediatr Pulmonol. © 2005 Wiley‐Liss, Inc.
Quantum spin correction scheme for ab initio spin‐unrestricted solutions: Multiple bonds case
Authors: Yamanaka Shusuke , Takeda Ryo , Shoji Mitsuo , Kitagawa Yasutaka , Honda Hiroaki , Yamaguchi Kizashi
Published: August 2005

A quantum spin‐correction scheme based on spin‐correlation functions is proposed for multiple bond‐breaking processes described by the unrestricted single determinant (USD) approaches, such as unrestricted Hartree–Fock (UHF) and unrestricted Kohn–Sham (UKS) density functional theory (DFT). It is known that natural orbitals (NOs) and occupation numbers (ONs) contain full information of USD solutions. We introduce a bond‐operator representation of UHF and UKS wave functions to exploit information about those NOs, enabling us not only to facilitate the calculus, but also to understand the essential feature of the USD and those quantum spin‐corrected solutions. We found that usual spin‐projected solutions do not work for multiple bonds in the Heisenberg model mapping scheme. We propose quantum spin‐correction schemes to obtain the spin‐symmetry allowed solutions from the spin‐unrestricted KS‐DFT solutions. We examine these schemes for a chromium dimer, which is a typical example exhibiting multiple bonds. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Erratum: Amlan K. Roy, “Studies on some singular potentials in quantum mechanics,” International Journal of Quantum Chemistry (2005) 104(6)861–870
Authors: Roy Amlan K.
Published: August 2005

The original article to which this Erratum refers was published in International Journal of Quantum Chemistry (2005)104(6) 861–870.
Significance of the simultaneous growth of vegetative and reproductive organs in the prostrate annual Chamaesyce maculata (L.) Small (Euphorbiaceae)
Authors: Suzuki Nobuhiko , Ohnishi Yoshihiro
Published: August 2005

To elucidate the significance of the simultaneous growth of vegetative and reproductive organs in the prostrate annual Chamaesyce maculata (L.) Small (Euphorbiaceae) from the standpoint of meristem allocation, we investigated plant architecture, meristem allocation, and the spatial and temporal patterns in vegetative growth and reproduction in the reproductive stage. The numbers of secondary and tertiary shoots successively increased by branching in the reproductive stage, and the sum of shoot length was greater in secondary shoots than in primary shoots. The specific shoot length (shoot length per shoot biomass) was greater in lateral shoots than in primary shoots, indicating efficient lateral shoot elongation. The internode length was shorter in secondary shoots than in primary shoots, increasing the number of nodes per shoot length in secondary shoots. Many nodes on a shoot generated two meristems, one of which committed to a flower and one to a lateral shoot. The number of reproductive meristems was greatest in tertiary shoots, and 96% of total reproductive meristems on shoots were generated in lateral shoots. On almost all nodes, the reproductive meristem developed into a flower, and 95–98% of the flowers produced a fruit. Therefore, vegetative growth by branching in the reproductive stage contributed to the increase in reproductive outputs. From the standpoint of meristem allocation, the simultaneous growth of vegetative and reproductive organs in prostrate plant species might be important for increasing the number of growth and reproductive meristems, resulting in the increase in reproductive outputs.
Does symptom‐limited cycle exercise cause low frequency diaphragm fatigue in patients with heart failure?
Authors: Dayer Mark J. , Hopkinson Nicholas S. , Ross Ewen T. , Jonville Sophie , Sharshar Tarek , Kearney Mark , Moxham John , Polkey Michael I.
Published: August 2005

Background:

Reduced diaphragm contractility occurs in some healthy subjects when they exercise to exhaustion. This indicates low frequency fatigue, which may contribute to task failure. We hypothesised that patients with congestive heart failure (CHF) might be especially vulnerable to the development of low frequency diaphragm fatigue after exhaustive exercise.

Aims:

To study the effect of exhaustive incremental cycle exercise on diaphragm contractility in patients with CHF.

Methods:

12 patients with CHF with an ejection fraction of 36.5±7.3% and 12 healthy age‐matched control subjects performed an incremental cycle test to exhaustion. The unpotentiated twitch transdiaphragmatic pressure (twitch Pdi) in response to bilateral anterolateral magnetic phrenic nerve stimulation (BAMPS) was measured before and after exercise.

Results:

Twitch Pdi at baseline was 20.2±6.7 cmH2O in the CHF group and 20.3±3 cmH2O in the controls (p=0.957). 25 and 35 min post exercise the values were 19.9±5.4 and 20.0±5.1 cmH2O in the CHF group and 20.6±4.3 and 21.2±3.4 cmH2O in the control group; neither change was significant (F(2,27)=0.007, p=0.993; F(2,33)=0.144, p=0.866, respectively).

Conclusion:

When patients with CHF cycle to exhaustion, low frequency fatigue of the diaphragm does not occur, and this is unlikely to be an important factor limiting exercise capacity of such patients.
Genesis of the P wave: Atrial signals as generated by the equivalent double layer source model
Authors: van Oosterom Adriaan , Jacquemet Vincent
Published: August 2005

Aim

To assess the effectiveness of the equivalent surface source model in the simulation of atrial signals as observed in ECG leads.

Methods

P waves were extracted from 64-lead ECGs recorded in healthy subjects. The geometries of torso, lungs, heart, and blood cavities of a healthy subject, derived from magnetic resonance imaging, were used to position a detailed, thick-walled 3D model of the atria consisting of a set of 800,000 units representing the activity of all atrial myocytes. The ion-kinetics of the units was based on the formulation of Courtemanche et al. The simulated transmembrane potentials following a normal sinus beat, as well as those during atrial fibrillation, were projected on the 1297 nodes of the surface encapsulating all atrial myocytes (endocardium and epicardium). The transmembrane potentials at these nodes formed the source strengths of the elements of the equivalent generator, which were used to compute body surface potentials.

Results

After invoking slight adaptations of the timing of depolarization of the transmembrane potentials, the simulated signals during the P wave closely corresponded to recorded ones. The correspondence during the entire PR interval improved markedly after the inclusion of early repolarization effects in the interval between the end of the P wave and onset of QRS. This demanded a shortening of the mean action potential duration generated by the Courtemanche model. The simulated ECGs related to atrial fibrillation demonstrated the characteristic features of those clinically observed.

Conclusions

The equivalent double layer is a useful source model for the genesis of atrial signals observed on the thorax. The interval from the end of the P wave to onset of QRS is not iso-electric. The Courtemanche model of the ion-kinetics of atrial cells needs to be adapted when applied to represent the activity of healthy, ‘common’ atrial myocytes.
Suppression of hypothalamic deiodinase type II activity blunts TRH mRNA decline during fasting
Authors: Coppola Anna , Hughes Jeniter , Esposito Emanuela , Schiavo Luigi , Meli Rosaria , Diano Sabrina
Published: August 2005

Fasting is characterized by disrupted thyroid feedback, with suppressed levels of thyroid hormones and paraventricular thyrotropin releasing hormone (TRH). We found that third ventricle administration of the deiodinase inhibitor, iopanoic acid, dose‐dependently reduced deiodinase type II (DII) activity selectively in the hypothalamus. This suppression of DII by iopanoic acid during fasting prevented elevated DII activity and blunted the decline in hypothalamic TRH mRNA levels. Because fasting‐induced elevation in hypothalamic DII activity is paralleled by increased hypothalamic T3 concentration, our study suggests that T3 formation by DII in the hypothalamus is the cause of disrupted thyroid feedback during fasting.
Histidine inhibits oxidative stress‐ and TNF‐α‐induced interleukin‐8 secretion in intestinal epithelial cells
Authors: Son Dong Ok , Satsu Hideo , Shimizu Makoto
Published: August 2005

We investigated the effect of several amino acids on the secretion of such inflammatory cytokines as interleukin‐8 (IL‐8) induced by hydrogen peroxide or tumor necrosis factor‐alpha (TNF‐α) in intestinal epithelial‐like Caco‐2 and HT‐29 cells. We found that histidine, one of the conditionally essential amino acids, significantly inhibited both hydrogen peroxide‐ and TNF‐α‐induced IL‐8 secretion and mRNA expression in Caco‐2 cells and HT‐29 cells. These inhibitions were dose dependent and the inhibition rate of hydrogen peroxide‐induced IL‐8 secretion reached more than 50% at a concentration of 25 mM, with over 95% inhibition at a concentration of 50 mM. TNF‐α increased the transcriptional activity of the IL‐8 promoter which was significantly inhibited by treating Caco‐2 cells with histidine. Histidine also abolished the NF‐κB‐dependent activation of the IL‐8 promoter induced by TNF‐α. These results indicate that histidine inhibited the hydrogen peroxide‐ and TNF‐α‐induced IL‐8 secretion at the transcriptional level in intestinal epithelial cells, suggesting that histidine has the potential to attenuate intestinal inflammation.
Implication of a critical residue (Glu175) in structure and function of bacterial luciferase
Authors: Madvar Ali Riahi , Hosseinkhani Saman , Khajeh Khosro , Ranjbar Bijan , Asoodeh Ahmad
Published: August 2005

Structural properties of a bacterial luciferase mutant, evolved by random mutagenesis, have been investigated. Bacterial luciferases (LuxAB) can be readily classed as slow or fast decay luciferases based on their rates of luminescence decay in a single turnover assay. By random mutagenesis, one of the mutants generated by a single mutation on LuxA at position 175 (E175G) resulted in the “slow decay” Xenorhabdus luminescens luciferase was converted into a luciferase with a significantly more rapid decay rate [Hosseinkhani, S., Szittner, R. and Meighen, E.A. (2005) Biochemical Journal 385, 575–580]. A single mutation (E175G), in a loop that connects α helix 5 and β sheet 5 brought about changes in the kinetic and structural properties of the enzyme. Enhancement of tryptophan fluorescence was observed with a lower degree of fluorescence quenching by acrylamide upon mutation. Near‐ and far‐UV circular dichroism spectra of the native and mutant forms suggested formation of an intermediate structure, further supported by 8‐anilino‐1‐naphthalene‐sulphonic acid (ANS) fluorescence which indicated lower exposure of hydrophobic residues as a result of mutation. Fluorescence quenching studies utilizing acrylamide indicated a more accessible fluor for the native form. Thus, the E175G point mutation appears to change the enzymatic decay rate by inducing a substantial tertiary structural change, without a large effect on secondary structural elements, as revealed by Fourier transform IR spectroscopy. Overall, the mutation caused structural changes that go beyond the simple change in orientation of Glu175.
Increased cellular cholesterol efflux in glycogen storage disease type Ia mice: A potential mechanism that protects against premature atherosclerosis
Authors: Nguyen Andrew D. , Pan Chi-Jiunn , Shieh Jeng-Jer , Chou Janice Yang
Published: August 2005

Glycogen storage disease type Ia (GSD‐Ia) patients manifest a pro‐atherogenic lipid profile but are not at elevated risk for developing atherosclerosis. Serum phospholipid, which correlates positively with the scavenger receptor class B type I (SR‐BI)‐mediated cholesterol efflux, and apolipoprotein A‐IV and E, acceptors for ATP‐binding cassette transporter A1 (ABCA1)‐mediated cholesterol transport, are increased in GSD‐Ia mice. Importantly, sera from GSD‐Ia mice are more efficient than sera from control littermates in promoting SR‐BI‐ and ABCA1‐mediated cholesterol effluxes. As the first step in reverse cholesterol transport, essential for cholesterol homeostasis, these observations provide one explanation why GSD‐Ia patients are apparently protected against premature atherosclerosis.
Arthrogryposis Multiplex Congenita
Authors: MENNEN ULRICH , VAN HEEST ANN , EZAKI MARY-BETH , TONKIN MICHAEL , GERICKE GEORGE
Published: August 2005

Since much confusion exists regarding arthrogryposis multiplex congenita (AMC), the President of the IFSSH commissioned the AMC Committee to compile a report on the various aspects of this condition. This report discusses all the facets of AMC, including definition, terminology, dermographics, aetiology, classification, clinical features, management, prognosis and further studies. Manipulation of the deformities starting soon after birth improves the range of motion, which, if surgery needs to be done, makes the operation less extensive. Sometimes surgery may not even be necessary. Early one-stage corrective surgery between 3 and 12 months of age is encouraged. This results in improved function and near normal cosmetic appearance. Late, piece-meal surgery results in disappointing outcome.
Epidermal Growth Factor Receptor (EGF-R) in Dupuytren’s Disease
Authors: AUGOFF K. , TABOłA R. , KULA J. , GOSK J. , RUTOWSKI R.
Published: August 2005

The aim of this paper was to examine participation of the epidermal growth factor receptor (EGF-R) signal pathway in the pathogenesis of Dupuytren’s disease. The study showed changes in the ratio of membrane EGF-R to its intracellular level during the different clinical stages of Dupuytren’s contracture progression. Our observations of a high ratio of surface to intracellular EGF-R in the palmar aponeurosis of patients with second degree of Dupuytren’s disease (Iselin’s classification), which was significantly higher than this ratio in control palmar fascia ( P = 0.022), would suggest that EGF-R has a role in the involutional phase of the disease.
The Politics of Remembrance in Irish and Quebec Nationalism
Authors: Stevenson Garth
Published: August 2005

Abstract. This article describes how the remembrance of
historical events contributes to, and is shaped by, nationalism in Ireland
and Quebec. Remembered historical events contribute to the growth of
nationalism if they serve at least one of five purposes: defining the
conceptual boundaries of the nation, reinforcing a sense of pride in the
nation's achievements, evoking feelings of pity and indignation at
the losses suffered by the nation, legitimizing the actions or principles
of present-day leaders, or inspiring a belief that the nation will
eventually triumph. Eight remembered events, four in Ireland and four in
Quebec, are discussed in relation to these five purposes. The article
concludes that historical remembrance has been a more powerful influence
on nationalism in Ireland than in Quebec.

Résumé. Cet article raconte comment le souvenir
des évenements historiques contribue au renforcement du
nationalisme en Irlande et au Québec. Le souvenir d'un
évenement historique aura cet effet s'il aide … definir
la communauté nationale,s'il stimule des sentiments de la
pitié et de l'indignation envers la nation et ses
tribulations, s'il légitime les actions et les idées
des nationalistes actuels, ou s'il encourage l'esperance que la
nation va triompher contre ses adversaires. L'article examine quatre
evenements historiques, irlandais ou québécois, avec le but
de déterminer s'ils contribuent … ces cinq objectifs.
Selon sa conclusion, l'influence des souvenirs historiques a
été plus puissante en Irlande q'au Québec, ce
qui explique la plus grande intensité du nationalisme
irlandais.
Chrétien and Canadian Federalism, Politics and the
Constitution, 1993–2003
Authors: Sheldrick Byron
Published: August 2005

Chrétien and Canadian Federalism, Politics and the
Constitution, 1993–2003, Edward McWhinney, Vancouver: Ronsdale
Press, 2003, pp. 220.

Edward McWhinney, a legal scholar and former professor of political
science, sat as the Member of Parliament for Vancouver Quadra through much
of the Chrétien period. The title of the book promises an
examination of the Chrétien era in terms of its legacy for Canadian
federalism and the constitution. Sadly, the book fails to deliver.
Although the author is quick to insist that his work is not a
“personal biography” (12), but rather an analysis framed
through “participant observation,” the examination of the past
decade's events is largely a form of political memoir, with little by
way of a sustained analysis of Canadian federalism or the
constitution.
La seconde Révolution tranquille—Démocratiser la
démocratie
Authors: de Champlain Olivier
Published: August 2005

La seconde Révolution tranquille—Démocratiser la
démocratie, Gil Courtemanche, Montréal, Boréal 2003,
172 p.

C'est bien à une seconde Révolution tranquille que
l'auteur-journaliste-essayiste Gil Courtemanche nous convie tout au
long de ce petit essai au ton pamphlétaire, écrit dans
l'euphorie consécutive au sommet de Porto Allegre.
Démocratiser la démocratie, voilà la véritable
finalité de cette seconde Révolution tranquille, qui,
contrairement à la première, devra venir de la base.
Still Counting: Women in Politics Across Canada
Authors: Goodyear-Grant Elizabeth
Published: August 2005

Still Counting: Women in Politics Across Canada, Linda Trimble and
Jane Arscott, Peterborough, ON: Broadview Press, 2003. pp. xvi, 210

Numbers matter. This is Trimble and Arscott's fundamental
message. The ratio of women in elected and appointed political posts to
their proportion in the population at large is a measure of fairness in
political representation that has obvious implications for women's
impact on political processes and policy outcomes. Although Canadian in
perspective, the authors draw international comparisons where appropriate
and find Canada rather lacking. Perennial under-representation, despite
marked improvements over the past three decades, is an evident problem and
an issue worthy of investigation.
Feminist Perspectives on Canadian Foreign Policy
Authors: Narain Nigmendra
Published: August 2005

Feminist Perspectives on Canadian Foreign Policy, Claire Turenne
Sjolander, Heather A. Smith and Deborah Steinstra, eds., Toronto: Oxford
University Press, 2003, pp. xiv, 246

This timely must-read collection of fourteen essays is a welcomed
addition to a growing body of feminist Canadian foreign policy literature.
It is an accessible collection which challenges traditional Canadian
foreign policy analyses (including feminist ones) by deploying feminist
approaches and presenting feminist foreign policy (re-)formulations. Each
author carefully explains relevant feminist theory or scholarship to link
tightly their theoretical arguments with their case studies.
Welfare Hot Buttons: Women, Work, and Social Policy Reform
Authors: Andrew Caroline
Published: August 2005

Welfare Hot Buttons: Women, Work, and Social Policy Reform, Sylvia
Bashevkin, Toronto: University of Toronto Press, 2002, pp. viii, 188.

Welfare Hot Buttons raises important, and in some ways
uncomfortable, questions. Its major argument, in comparing social policy
reform in the United States, the United Kingdom and Canada, is that the
conservative leaders (Ronald Reagan, George Bush Sr., Margaret Thatcher,
John Major, Brian Mulroney, Kim Campbell) were, in their social policy
reforms, less punitive, less restrictive and less obsessed with paid work
than their post-conservative successors (Bill Clinton, Tony Blair, Jean
Chrétien). This raises important questions about the importance of
elections and of elected politicians. There were real expectations that,
to take the Canadian example, electing Chrétien's Liberals was
a major shift away from Mulroney's Conservatives yet, as Sylvia
Bashevkin shows, this was not true in the vital policy area of social
policy reform.
Imagining Interest in Political Thought: Origins of Economic
Rationality
Authors: Hocutt Max O.
Published: August 2005

Imagining Interest in Political Thought: Origins of Economic
Rationality, Stephen G. Engelmann, Durham and London: Duke University
Press, 2003, pp. x, 194

This always fascinating but sometimes frustrating volume undertakes to
trace the natural history of what its author calls
neo-liberalism, meaning the kind of economic analysis and
approach to governance practiced by such denizens of the Chicago school as
Nobel Prize winner Gary Becker and appeals court Justice Richard Posner. A
professor at the University of Illinois in Chicago, Engelmann contends
that this mode of analysis grew out of a way of thinking that was brought
to maturity by Jeremy Bentham but had already begun to take root in
Cromwell's England.
The Logic of Political Survival
Authors: Warwick Paul
Published: August 2005

The Logic of Political Survival, Bruce Bueno de Mesquita, Alastair
Smith, Randolph Siverson, and James Morrow, Cambridge, MA and London: The
MIT Press, 2003, pp. xiii, 536

The Logic of Political Survival is much more than its title
suggests. Its main focus is certainly on the survival of political
leaders, but its embrace extends to economic development, nation-building,
democratization, war and peace, protest, civil war, and revolution. All of
these topics are subsumed under a single theory that is elaborated
formally and validated through a truly gargantuan exercise in data
analysis. It is, without doubt, an extraordinary attempt to answer some
very big questions.
La politique étrangère des États-Unis.
Fondements, acteurs, formulation
Authors: Deschênes Dany
Published: August 2005

La politique étrangère des États-Unis.
Fondements, acteurs, formulation, Charles-Philippe David, Louis Balthazar
et Justin Vaïsse, Paris : Presses de sciences po, 2003, 382 p.

Avec l'avènement de l'administration de George W.
Bush et les suites des attentats de septembre 2001, l'étude de
la politique étrangère des États-Unis, en langue
française, connaît un dynamisme renouvelé. Plusieurs
travaux récents, dont ceux de Jean-Yves Haine et de Sabine Lavorel
respectivement sur la politique américaine face à
l'Alliance atlantique et sur la formulation de la politique de
sécurité nationale sous G.W. Bush, sont des exemples qui
illustrent bien cette tendance.
Critical Political Studies: Debates and Dialogues from the
Left
Authors: Chorney Harold
Published: August 2005

Critical Political Studies: Debates and Dialogues from the Left,
Abigail B. Bakan and Eleanor MacDonald, eds., Montreal:
McGill-Queen's University Press, 2002, pp. xiv, 432

For political observers, scholars, analysts and practitioners on the
left the last two decades have been very difficult. With the rise of
globalization, the decline of the Keynesian welfare state, the triumph of
Thatcherism, Reaganism and Mulroneyism and the decade long dominance of
neo-liberalism in Canada, a great deal of creative rethinking has become
necessary—not only for the socialist left, but also for social
democrats, left liberals and red tories.
Hegel on Ethics and Politics
Authors: Pellerin Daniel
Published: August 2005

Hegel on Ethics and Politics, Robert B. Pippin and Otfried Höffe,
eds., translated by Nicholas Walker; The German Philosophical Tradition
Series; Cambridge and New York: Cambridge University Press, 2004, pp.
358

In a better world, all books involving Kant or Hegel might come with a
reverse price tag. Instead of making prospective readers pay for the
privilege, they would encourage and reward the gruelling labour facing
those who would brave the convoluted prose, the merciless grind of
thousand-word paragraphs lecturing in German no matter the language in
which they appear to be written. In our own world, of course, such learned
works tend to be especially expensive, a whopping hundred dollars in this
case.