bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cell‐specific expression pattern of monocarboxylate transporters in astrocytes and neurons observed in different mouse brain cortical cell cultures
Authors: Debernardi Ruth , Pierre Karin , Lengacher Sylvain , Magistretti Pierre J. , Pellerin Luc 
Published: October 2004

AbstractEvidence suggests that lactate could be a preferential energy substrate transferred from astrocytes to neurons. Such a process implies the presence of specific monocarboxylate transporters on both cell types. Expression of MCT1 and MCT2, two isoforms of the monocarboxylate transporter (MCT) family, was studied in enriched cultures of mouse cortical astrocytes or neurons. It was observed that, at both the mRNA and the protein levels, astrocytes strongly expressed MCT1 but had very little if any MCT2. By contrast, neurons had high amounts of MCT2 mRNA, although MCT1 mRNA was also detected. Double immunofluorescent labelings with appropriate markers confirmed the cell‐specific preference in the expression of MCT1 and MCT2, but they revealed that a subset of neurons expresses low to moderate levels of MCT1. Parallel immunocytochemical stainings of cultured neurons with the presynaptic marker synaptophysin showed that MCT2 expression is correlated with synaptic development. Although MCT2 and synaptophysin were not colocalized, their distribution was similar, and they were often closely apposed, suggesting that MCT2 could be associated with postsynaptic terminals. Interaction between astrocytes and neurons, as occurring in layered cultures, did not modify the levels of MCT1 and MCT2 expression or their distribution and cell‐specific preference under the conditions used. However, a close apposition between neurites and MCT1‐expressing astrocytic processes was apparent and developed as cultures evolved. In addition to providing an extensive description of MCT distribution in cultured cells, our data underscore the potential of such preparations for future studies on the regulation of MCT expression. © 2003 Wiley‐Liss, Inc.
Preparation of Carboxyl‐Functionalized Polystyrene/Silica Composite Nanoparticles
Authors: Zeng Zhong , Yu Jian , Guo Zhao‐Xia 
Published: October 2004

AbstractSummary: This paper describes the synthesis of carboxyl‐functionalized polystyrene/silica (PS/SiO2) composite nanoparticles with various contents of poly(methacrylic acid) (PMAA) on the surface by post‐addition of methacrylic acid (MAA) via emulsion polymerization. High yields and binding efficiencies (around 90%) are achieved by an optimal procedure mainly involving the appropriate addition of MAA and amounts of surfactant and silica. The kinetics investigated indicates that the polymerization follows a mechanism different than that found in some earlier studies. The amount of grafted PMAA was determined by titration and FT‐IR, and altered in a wide range (1–40 wt.‐% to PS). Transmission electron microscopy (TEM) photographs show that the composite nanoparticles are about 60 nm in spherical shape and have a multi‐layered core‐shell structure with a cluster of primary silica beads as the core and PMAA as the outmost shell. There are approximately 4 to 21 primary silica beads in one composite nanoparticle, depending on the amount of silica added.Preparation of carboxyl‐functionalized polystyrene(PS)/silica composite nanoparticles.magnified imagePreparation of carboxyl‐functionalized polystyrene(PS)/silica composite nanoparticles.
Untersuchung tribologischer Schichtsysteme mit dem Spiraltribometer
Authors: Bethke R. , Bewilogua K. 
Published: October 2004

AbstractMessungen mit einer Kugel‐Scheibe‐Anordnung im Spiralmode liefern zusätzliche Informationen zum tribologischen Verhalten von Reibpaarungen, da sich die Ausbildung von Transferschichten bzw. Ablagerungen durch adhäsiven Verschleiß anders darstellt als in Testversuchen im Kreismode. Damit ist insbesondere die Möglichkeit gegeben, die tribologische Situation offener Tribosysteme besser darzustellen und messtechnisch zu erfassen. Sowohl im Spiral‐ als auch im Kreismode wurden Reibkoeffizienten verschiedener Reibpaarungen ermittelt, wobei mindestens ein Reibpartner beschichtet war. Die getesteten Schichtmaterialien waren diamantähnlicher Kohlenstoff (DLC/a‐C:H), Wolfram(W)‐haltiges DLC (W‐DLC/a‐C:H:W) und Chromnitrid (CrN). Nachfolgend werden für die beiden DLC‐basierten Schichtmaterialien nur noch die heute üblichen Bezeichnungen a‐C:H und a‐C:H:W verwendet.
Tribologische Versuche an modifizierten Gewindefurchern
Authors: Schäfer M. , Tikal F. 
Published: October 2004

AbstractGewindefurchen als umformendes Gewindefertigungsverfahren bietet gegenüber der spanenden Innengewindeherstellung wirtschaftliche und technologische Vorteile, wie z. B. keine Spanentsorgung und höhere Festigkeit der Gewindeflanken. Um das Gewindefurchen nicht nur als Gesamtumformprozess betrachten zu können, wurde ein Verfahren entwickelt, das es ermöglicht, die gleichzeitig ablaufenden Umformprozesse am Werkzeug getrennt voneinander zu betrachten. Durch die Modifizierung herkömmlicher Gewindefurcher kann jede Umformstufe separat gefertigt und die dabei auftretenden Kräfte und mechanischen Belastungen ermittelt werden. Da die Reibungszahl μ immer vom jeweiligen Bearbeitungsverfahren und Prozessparametern abhängig ist, kann sie nur experimentell ermittelt werden. Dies ist mit Hilfe des entwickelten Verfahrens am realen Formkeil möglich und wird für verschiedene Prozessparameter, wie z. B. die Werkzeugbeschichtung, Werkstückumfangsgeschwindigkeit und Werkstücktemperatur, durchgeführt.
Heterotopic limb allotransplantation model to study skin rejection in the rat
Authors: Nazzal Jamal A. , Johnson Timothy S. , Gordon Chad R. , Randolph Mark A. , Lee W.P. Andrew 
Published: October 2004

AbstractCurrent rodent models for investigation of limb allotransplantation typically utilize orthotopic whole‐limb transplantation, a morbid and time‐consuming procedure. Our objective was to design a less morbid rat model to explore the immunological obstacles of limb transplantation, and particularly skin. Twenty lower hindlimbs from 10 donors were transplanted into a heterotopic subcutaneous position into 20 animals (10 isogeneic and 10 allogeneic). Each group was further subdivided to include animals with (n = 5) and without (n = 5) a skin paddle for observation of cutaneous signs of rejection. All grafts in the isogeneic group survived for 100 days, i.e., the endpoint of the study. Allogeneic transplants rejected their allografts at a mean of 12.8 days (with skin) and 20.6 days (without). Our heterotopic limb transplantation model takes less time and is less stressful to the animals, while allowing for early observation of graft skin rejection, when compared to orthotopic whole‐limb transplantation. © 2004 Wiley‐Liss, Inc. Microsurgery 24:448–453, 2004.
New experimental flap model in the rat: Free flow‐through epigastric flap
Authors: Özkan Ömer , Coşkunfirat O. Koray , Özgentaş H. Ege , Dikici M. Bahadir 
Published: October 2004

AbstractThis study describes a free flow‐through flap model in the rat for use in the evaluation of the physiologic and hemodynamic characteristics of this type of flap in clinical practice. The rat is a preferred animal model because it is inexpensive, readily available, and reliable. There is no free flow‐through flap model available for laboratory animals, although this model gained popularity in clinical use recently. Twenty Wistar rats weighing 200–250 g were used in our experiment. In 5 rats, the vascular anatomy of the groin and proximal thigh region was determined by anatomic dissection. The experimental design consisted of two groups. In the experimental group (N = 5), a flow‐through epigastric skin flap was harvested based on the femoral artery, preparing both its proximal and distal stumps. The flap was transferred to the contralateral groin, and end‐to‐end vascular anastomosis was performed between a proximal and distal stump of the femoral arteries of the flap and recipient site. The proximal stump of the femoral vein of the flap was anastomosed to the femoral vein of the recipient site. The control group was divided into two subgroups. In all control group rats (N = 10), the flap was harvested in the same manner, and transferred to the contralateral groin, but standard free‐flap procedure with one artery and one vein anastomosis was performed in 5 rats (conventional free‐flap subgroup), and anastomosis was not performed between the flap and the recipient site in the remaining 5 rats (graft subgroup). Survival of the flap was evaluated on postoperative day 7 by direct observation, and microangiography was performed to delineate the vascularity of the flow‐through flap. The results showed that all flaps survived in the experimental group and the conventional free‐flap subgroup of the control group, whereas in the graft subgroup, all flaps underwent total necrosis. The authors conclude that the flow‐through epigastric flap for the rat is a simple and reliable model for future physiologic and pharmacologic studies. © 2004 Wiley‐Liss, Inc. Microsurgery 24:454–458, 2004.
Design of a high‐directivity Electromagnetic Band Gap (EBG) resonator antenna using a frequency‐selective surface (FSS) superstrate
Authors: Lee Young Ju , Yeo Junho , Mittra Raj , Park Wee Sang 
Published: October 2004

AbstractIn this paper, we introduce a novel design for a high‐directivity Electromagnetic Band Gap (EBG) resonator antenna that utilizes a frequency‐selective surface (FSS) superstrate. The above type of superstrate is proposed as an alternative to an EBG type of dielectric superstrate—investigated previously by the authors—to reduce its height and facilitate the fabrication process. Although FSS superstrate and the patch antenna comprise a composite resonator, we begin by investigating the FSS structure characteristics first before dealing with the combination. We vary several important parameters, such as the distance between the FSS superstrate and the ground plane of the antenna, and the dimensions of the FSS superstrate, to determine their effect on the resonant frequency and the quality factor of the unit cell of the FSS. The above study enables us to derive some guidelines for an optimum array size of the FSS superstrate that eventually leads to a maximum directivity for the FSS antenna composite, as evidenced via a comparison of the quality factors of the FSS, the unit cell, and the composite. It is demonstrated that the directivity of the antenna with an optimized array size of the FSS superstrate increases by 17.29 to 24.92 dBi for three different strip‐dipole lengths, as compared to that of the patch antenna alone (maximum 6 dBi). © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 462–467, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20502
Multiband capacitively loaded magnetic dipole
Authors: Poilasne G. , Rowson S. , Desclos L. 
Published: October 2004

AbstractCapacitively loaded magnetic dipoles (CLMDs) are small antennas that are easily integrated inside mobile devices for either single or multiband applications. They can be analyzed using different approaches. Treated as regular antennas, these dipoles are versatile for implementation as they offer very high efficiency and low interaction with the surrounding components. Treated as frequency filters, they can help reduce the component count or ease the specification. Finally, treated as spatial and polarization filters, they provide very powerful solutions for diversity implementation. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 475–478, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20506
Simultaneous independent temperature and strain measurement using one fiber Bragg grating based on the etching technique
Authors: Xiaohong Li , Dexiang Wang , Fujun Zhao , Enguang Dai 
Published: October 2004

AbstractA new method for the simultaneous and independent measurement of temperature and strain that employs only one FBG based upon the etching technique is demonstrated both theoretically and experimentally. The sensor using this scheme has a small sensor probe, and offers combined characteristics of compactness, effective cost, and easy fabrication. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 478–481, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20507
Gain clamping in double‐pass L‐band EDFA using a ring resonator
Authors: Harun S. W. , Samsuri N. MD , Ahmad H. 
Published: October 2004

AbstractA gain‐clamped long‐wavelength‐band erbium‐doped fiber amplifier (L‐band EDFA) based on a ring‐laser cavity is demonstrated using two C/L‐band wavelength‐selective couplers. This new design provides improved gain characteristics and high tuneability. The gain is clamped at 11.5 dB with a gain variation of less than 0.1 dB from an input‐signal power of −40 to −6 dBm by setting the variable attenuation setting (VOA) at 8 dB. Also, the clamped‐gain level can be controlled to be in the range from 4.7 to 21.3 dB by varying the VOA settings from 0 to 24 dB. However, the proposed gain‐clamped amplifier suffers from noise‐figure degradation, as compared to the open‐ring amplifier, due to the intense ring‐laser light, which counter‐propagates through the EDF. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 484–486, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20509
Design of multiple U‐shaped slot microstrip patch antenna for 5‐GHz band WLANs
Authors: Ju Jeong Min , Jeong Gyey‐Teak , Yoon Joong‐Han , Ko Sung‐Won , Kwak Kyung‐Sup 
Published: October 2004

AbstractIn this study, a multiple U‐shaped slot microstrip patch antenna for application in the 5‐GHz band is designed and fabricated. To obtain sufficient bandwidth in the operating band, foam is inserted between the substrate and ground plane, a coaxial probe source is used, and the position of the probe shift is adjusted from the center to the left. The measured result (5.02–5.955 GHz) of the fabricated antenna satisfies the conditions of VSWR < 2.0 in 5‐GHz band (5.15–5.35 GHz, 5.47–5.725 GHz, and 5.725–5.825 GHz): gain of 3.88–9.28 dBi and broad radiation pattern. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 486–488, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20510
A practical scheme for envelope delta‐sigma modulated (EDSM) microwave power amplifier
Authors: Dupuy Alexandre , Wang Yuanxun Ethan 
Published: October 2004

AbstractA delta‐sigma modulated Class‐E power amplifier is proposed and experimentally developed for high‐efficiency linear applications. The essential idea is based on the envelope delta‐sigma modulation (EDSM), which combines the Kahn technique, envelope elimination and restoration (EER), with the Delta‐Sigma modulated‐amplifier concept. The scheme increases the efficiency of the circuit by digitalizing the envelope of the signal instead of the original RF signal. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 491–495, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20512
Dynamic polarization‐dependent loss (DPDL) of planar‐waveguide‐based variable optical attenuators (VOAs)
Authors: Zhang Zhiyi , Xiao Gao Zhi , Grover Chander P. 
Published: October 2004

AbstractWe analyze the dynamic polarization‐dependent loss (DPDL) of planar‐waveguide‐based variable optical attenuators (VOAs). Our studies show that thermal stress is introduced in waveguides when heat is applied to achieve optical attenuation of Mach–Zehnder interferometer (MZI) coupler‐based VOAs made of silica, thus resulting in an unacceptable DPDL for such devices. The stress and its associated DPDL can be reduced significantly if two trenches are created along the waveguides. The DPDL can be further reduced to a negligible level by adopting a new VOA design based on straight waveguides and a silica–polymer hybrid structure. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 498–501, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20514
Microwave characterization of breast‐phantom materials
Authors: Bindu G. , Lonappan Anil , Thomas Vinu , Hamsakkutty V. , Aanandan C. K. , Mathew K. T. 
Published: October 2004

AbstractCorn syrup and glycerine are proposed as suitable breast‐phantom materials. These materials when diluted with water in definite proportions can serve as phantoms for normal, benign, and malign breast‐tissue samples. Dielectric permittivity and conductivity studies of these materials are performed using the cavity‐perturbation technique in the frequency range of 2.4–3.2 GHz. The results are compared with the in vitro breast‐tissue data and good agreement is reported. These materials are also useful as coupling media in microwave medical imaging. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 506–508, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20517
Varactor‐tunable and dipole‐grid‐based frequency‐selective surface
Authors: Mias C. 
Published: October 2004

AbstractA novel tunable frequency‐selective surface (FSS) filter configuration that can simultaneously block both vertical and horizontal polarizations is proposed. It consists of dipole elements tuned by low‐cost varactor diodes that are biased by multilayer grids. Single and series‐pair diode implementations are presented. The filter's tunable performance is demonstrated numerically and experimentally at around 2.45 GHz. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 508–511, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20518
Cross‐shaped fractal antenna: A compact circularly polarized radiating element
Authors: Abdillah M. Ben , Pascal O. , Aubert H. 
Published: October 2004

AbstractA novel topology for compact circularly polarized antennas is proposed. The cross‐shaped fractal antenna (CSFA) consists of two identical prefractal dipoles that are excited with a 90° time‐phase difference between them. Such an antenna significantly reduces the space filling, compared to classical topologies, and radiates excellent circularly polarized fields over a large beamwidth. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 518–521, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20521
High‐K EBG substrates for phase‐array patch‐antenna configurations
Authors: Galarregui Juan Carlos Iriarte , Ederra Iñigo , García Ramón Gonzalo , de Maagt Peter 
Published: October 2004

AbstractThis paper deals with the design of circularly polarised patch‐antenna arrays on high‐K material substrates. The use of these materials in combination with an EBG structure to prevent the excitation of substrate modes leads to the possibility of designing scanning arrays without suffering from grating lobes and scan‐blindness limitations. The proposed antenna configuration was used in both a single‐element and an array configuration. Highly efficient configurations together with smooth radiation patterns with low back radiation and high directivities were obtained. The array configuration showed a very broad scanning angle (140°) without suffering from grating lobes. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 527–532, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20524
An InGaP‐GaAs HBT low‐noise amplifier for 2.4/5.2/5.7‐GHz WLAN applications
Authors: Lin Yo‐Sheng , Chen Chih‐Chen 
Published: October 2004

AbstractA 2.4/5.2/5.7‐GHz triple‐band low‐noise amplifier (LNA) achieved by switching between different base bias currents (IB) using InGaP‐GaAs HBT technology is reported for the first time. Transducer gains (S21) of 14.6 and 11/9.5 dB, input return losses (S11) of −18.7 and −21.0/−11.5 dB, output return losses (S22) of −20 and −22.7/−24.9 dB, reverse isolation (S12) of −50.5 and −44.4/−44.4 dB, and noise figures of 3.35 and 2.54/2.71 dB were achieved at 2.4 and 5.2/5.7 GHz, respectively. The input 1‐dB compression point (P1dB) and input 3rd‐order intercept point (IIP3) of −8.5 and −1 dBm, respectively, were also achieved at 5.2 GHz. The power consumptions are only 7.6 and 3.6 mW for the 2.4‐ and 5.2/5.7‐GHz bands, respectively. The LNA only occupies an area of 300 × 500 μm, excluding the test pads because only one inductor is used. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 539–542, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20528
Fault Hamiltonicity and fault Hamiltonian connectivity of the (n, k)‐star graphs
Authors: Hsu Hong‐Chun , Hsieh Yi‐Lin , Tan Jimmy J. M. , Hsu Lih‐Hsing 
Published: October 2004

AbstractIn this paper, we consider the fault Hamiltonicity, and the fault Hamiltonian connectivity of the (n, k)‐star graph Sn,k. Assume that F ⊂ V(Sn,k) ∪ E(Sn,k). For n − k ≥ 2, we prove that Sn,k − F is Hamiltonian if |F| ≤ n − 3 and Sn,k − F is Hamiltonian connected if |F| ≤ n − 4. For n − k = 1, Sn,n−1 is isomorphic to the n‐star graph Sn which is known to be Hamiltonian if and only if n > 2 and Hamiltonian connected if and only if n = 2. Moreover, all the bounds are tight. © 2003 Wiley Periodicals, Inc.
A polynomial‐time approximation scheme for the minimum‐connected dominating set in ad hoc wireless networks
Authors: Cheng Xiuzhen , Huang Xiao , Li Deying , Wu Weili , Du Ding‐Zhu 
Published: October 2004

AbstractA connected dominating set in a graph is a subset of vertices such that every vertex is either in the subset or adjacent to a vertex in the subset and the subgraph induced by the subset is connected. A minimum‐connected dominating set is such a vertex subset with minimum cardinality. An application in ad hoc wireless networks requires the study of the minimum‐connected dominating set in unit‐disk graphs. In this paper, we design a (1 + 1/s)‐approximation for the minimum‐connected dominating set in unit‐disk graphs, running in timenO((slogs)2). © 2003 Wiley Periodicals, Inc.
Hygienic behavior in the honey bee (Apis mellifera L.) and the modulatory role of octopamine
Authors: Spivak Marla , Masterman Rebecca , Ross Rocco , Mesce Karen A. 
Published: October 2004

AbstractHoney bees, Apis mellifera, which perform hygienic behavior, quickly detect, uncap and remove diseased brood from the nest. This behavior, performed by bees 15–20 days old and prior to foraging, is likely mediated by olfactory cues. Because the neuromodulator octopamine (OA) plays a pivotal role in olfactory‐based behaviors of honey bees, we examined whether bees bred for hygienic and nonhygienic behavior differed with regard to their OA expression and physiology. We compared the staining intensity of octopamine‐immunoreactive (OA‐ir) neurons in the deutocerebral region of the brain, medial to the antennal lobes, between hygienic and nonhygienic bees (based on genotype and phenotype). We also tested how the olfactory responses of the two lines, based on electroantennograms (EAGs), were affected by oral administration of OA and of epinastine, a highly specific OA antagonist. Our results revealed that bees expressing hygienic behavior (irrespective of genotype) possessed OA‐ir neurons that exhibited more intense labeling than same‐aged bees not performing the behavior. In bees bred for nonhygienic behavior, OA significantly increased the EAG response to low concentrations of diseased brood odor. Conversely, in bees bred for hygienic behavior, epinastine significantly reduced the magnitude of the EAG response, a reduction not observed in nonhygienic bees. Our results provide two lines of evidence that OA has the potential to facilitate the detection and response of honey bees to diseased brood. We discuss the contributions of OA for behavioral shaping and its ability to bias the nervous system to express one form of behavior over another. © 2003 Wiley Periodicals, Inc. J Neurobiol 55: 341–354, 2003