bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of essential hypertension on kidney function as measured in rat by dynamic MRI
Authors: Laurent Didier , Poirier Kevin , Wasvary James , Rudin Markus 
Published: September 2002

AbstractIn this study, dynamic MRI was applied to investigate the effect of genetic hypertension on the renal clearance of Gd(DTPA). Assuming that the paramagnetic agent was essentially cleared through the kidney by glomerular filtration, a first‐order kinetic model was used to estimate a rate constant kcl describing the transport from the renal cortex to the inner medulla. Experiments were carried out on 12–15‐week‐old spontaneously hypertensive rats (young‐SHR) and age‐matched Wistar‐Kyoto rats (young‐WKY). An additional group of 22–25‐week‐old SHR (old‐SHR) was investigated to assess the long‐term effect of chronic hypertension on kidney function. The glomerular filtration rate as measured by the inulin method correlated well with kcl results as measured by MRI. A clearance index 30% lower than young‐WKY was observed in young‐SHR, reflective of a kidney dysfunction. In old‐SHR, kcl was only 50% of the young‐WKY value. As computed from Gd(DTPA) concentration profiles, this translated into delayed time‐to‐peak (TTP) values, decreased peak Gd(DTPA) concentrations ([Gd]peak), and a slow elimination of Gd(DTPA) from the blood pool, renal cortex, and inner medulla (e.g., high t1/2 values). Finally, using the same MRI approach, the data showed that the acute administration of the calcium antagonist verapamil at an antihypertensive dose was followed by a near normalization of SHR renal function. These results indicate that chronic hypertension remains a major pathogenic factor in the progression of glomerular degeneration, as opposed to a primary glomerular defect independent of systemic pressure. Magn Reson Med 47:127–134, 2002. © 2002 Wiley‐Liss, Inc.
Effect of age on muscle functions investigated with surface electromyography
Authors: Merletti Roberto , Farina Dario , Gazzoni Marco , Schieroni Maria Pia 
Published: September 2002

AbstractThe purpose of this study was to investigate changes in the surface electromyographic (EMG) signal as a means of defining age‐related central and peripheral mechanisms affecting muscle fatigue. Spectral and temporal variables of the surface EMG signal were studied during voluntary isometric contractions of the dominant biceps brachii muscle in a group of 8 healthy elderly men (age range 67–86 years) and a group of 10 healthy young men (age range 23–34 years). The maximal torque developed and the rate of decrease (slope) of spectral variables and conduction velocity (CV) were statistically higher in the young subjects than in the elderly subjects. Motor unit (MU) CV distribution was also estimated from the surface EMG signal and no statistical difference was observed in its variance between the two groups. These results confirm previous findings from the tibialis anterior muscle. Thus, changes in fiber type distribution and decrease in MU firing rate with aging may be factors determining the decrease in maximal voluntary contraction torque and in myoelectric manifestations of muscle fatigue. © 2002 John Wiley & Sons, Inc. Muscle Nerve 25: 65–76, 2002
Neuronal differentiation and long‐term survival of newly generated cells in the olfactory midbrain of the adult spiny lobster, Panulirus argus
Authors: Schmidt Manfred 
Published: September 2002

AbstractThe fate of continuously generated cells in the soma clusters of the olfactory midbrain of adult spiny lobsters, Panulirus argus, was investigated by in vivo pulse‐chase experiments with the proliferation marker 5‐bromo‐2′‐deoxyuridine (BrdU) combined with immunostainings for neuropeptides of mature neurons. A BrdU injection after a survival time (ST) of 14 h labeled about 100 nuclei in the lateral soma clusters (LC), comprised of projection neurons, and about 30 nuclei in the medial soma clusters (MC), comprised of local interneurons. The BrdU‐positive nuclei were confined to small regions at the inside of these clusters, which also contain nuclei in different phases of mitosis and thus represent proliferative zones. After STs of 2 weeks or 3 months, the number of BrdU‐positive nuclei was doubled, indicating a mitosis of all originally labeled cells. Dependent on ST, the BrdU‐positive nuclei were translocated from the proliferative zones towards the outside of the clusters, where somata of mature neurons reside. Immunostainings with antibodies to the neuropeptides FMRFamide and substance P, both of which label a large portion of somata in the MC and a pair of giant neurons projecting into the LC, revealed that in both clusters the proliferative zones are surrounded by, but are themselves devoid of, labeling. In the MC, some BrdU‐positive somata were double‐labeled by the FMRFamide antibody after an ST of 3 months, and by the substance P antibody after STs of 6 and 11/14 months, but not after 3 months. In the LC, BrdU‐positive somata after an ST of 3 months partially and after 6 and 11/14 months widely overlapped with the arborizations of the giant neurons, indicating the establishment of synaptic input. The experiments show that cells generated in proliferative zones in the LC and MC of adult spiny lobsters after a final mitosis differentiate into neurons within months, survive for at least 1 year, and are integrated into the circuitry of the olfactory midbrain. A new hypothesis about the mechanism of adult neurogenesis in the central olfactory pathway of decapod crustaceans is developed, linking it to neurogenesis during embryonic and larval development. © 2001 John Wiley & Sons, Inc. J Neurobiol 48: 181–203, 2001
Localization and imaging of local shunts in solar cells using polymer‐dispersed liquid crystals
Authors: Schmidt Jan , Dierking Ingo 
Published: September 2002

AbstractAn easy‐to‐use technique for the localization and imaging of local shunts in solar cells is introduced. The method is based on temperature‐sensitive polymer‐dispersed cholesteric liquid crystal foils, covering the reverse‐biased solar cell. The unique optical properties of the cholesteric liquid crystal, known as selective reflection, render the local shunts of a solar cell visible as a color distribution in the foil, which is directly correlated with the spatial shunt distribution. The novel method is applied to several laboratory and commercial silicon solar cells and its high sensitivity is demonstrated. Copyright © 2001 John Wiley & Sons, Ltd.
Cross‐resistance and inheritance of resistance to Bacillus thuringiensis toxin Cry1Ac in diamondback moth (Plutella xylostella L) from lowland Malaysia
Authors: Sayyed Ali H , Wright Denis J 
Published: September 2002

AbstractA field population of Plutella xylostella from Malaysia (SERD4) was divided into five sub‐populations and four were selected (G2–G5) with the Bacillus thuringiensis insecticidal crystal (Cry) toxins Cry1Ac, Cry1Ab, Cry1Ca and Cry1Da. Bioassay at G6 gave resistance ratios of 88, 5, 2 and 3 for Cry1Ac, Cry1Ab, Cry1Ca and Cry1Da respectively compared with the unselected sub‐population (UNSEL‐SERD4). The Cry1Ac‐selected population showed little cross‐resistance to Cry1Ab, Cry1Ca and Cry1Da, (3‐, 2‐ and 3‐fold compared with UNSEL‐SERD4), whereas the Cry1Ab‐SEL sub‐population showed marked cross‐resistance to Cry1Ac (40‐fold), much greater than Cry1Ab itself. In contrast, the Cry1Ca‐ and Cry1Da‐SEL sub‐populations showed little if any cross‐resistance to Cry1Ac and Cry1Ab. The mode of inheritance of resistance to Cry1Ac was examined in Cry1Ac‐selected SERD4 by standard reciprocal crosses and back‐crosses using a laboratory insecticide‐susceptible population (ROTH). Logit regression analysis of F1 reciprocal crosses indicated that resistance to Cry1Ac was inherited as an incompletely dominant trait. At the highest dose of Cry1Ac tested, resistance was recessive, while at the lowest dose it was almost completely dominant. The F2 progeny from a back‐cross of F1 progeny with ROTH were tested with a concentration of Cry1Ac that would kill 100% of ROTH. The mortality ranged between 50 and 95% in seven families of back‐cross progeny, which indicated that more than one allele on separate loci were responsible for resistance to Cry1Ac.© 2001 Society of Chemical Industry
Calculation of quasiparticle energy of molecular systems by the GW method
Authors: Ohta Y. , Maki J. , Yoshimoto T. , Shigeta Y. , Nagao H. , Nishikawa K. 
Published: September 2002

AbstractThe quasiparticle energy of the H2 molecule is calculated by using the GW method, in which the self‐energy operator fully depends on the frequency. The initial Green function G0 is constructed from the wave function obtained by the Hartree–Fock approximation (HFA) and local density approximation (LDA) in the framework of the density functional theory (DFT). From the results obtained we have shown that the wave function from the DFT–LDA is more effective than that from the HFA for G0. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 348–353, 2001
Generalized spin orbital GW theory for spin‐frustrated and spin‐degenerate systems
Authors: Yamanaka S. , Shigeta Y. , Ohta Y. , Yamaki D. , Nagao H. , Yamaguchi K. 
Published: September 2002

AbstractWe proposed the ab initio linear combination of Gaussian type orbital (LCGTO) generalized spin orbital GW (GSO–GW) method and calculated triangular hydrogen molecules as models of the noncolinear magnetic clusters. A remarkable improvement of ionized potentials (IPs) by the GW procedure for GHFS solutions is observed in comparison with calculational results by full CI. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 369–374, 2001
An atomic capacitance–polarizability model for the calculation of molecular dipole moments and polarizabilities
Authors: Jensen Lasse , Åstrand Per‐Olof , Mikkelsen Kurt V. 
Published: September 2002

AbstractA classical interaction model for the calculation of molecular polarizabilities has been investigated. The model is described by atomic capacitancies, polarizabilities, and a parameter related to the size of the atom, where one set of parameters has been employed for each element. The model has been parameterized for the elements H, C, N, O, F, and Cl from quantum chemical calculations of the molecular polarizability and dipole moment for 161 molecules at the Hartree–Fock level. The atomic charge has been divided into a nuclear charge and an electronic contribution, which also allows for modeling the permanent molecular dipole moment. Results are presented for polyenes. Excellent agreement with quantum chemical calculations is obtained for the components of the polarizability perpendicular to the chain, but the results are less satisfying for the component along the chain. An inherent deficiency of using atomic capacitancies for large molecules and long chains is discussed. © 2001 John Wiley & Sons, Inc. Int J Quant Chem, 2001
A novel approach for identification and measurement of hemoglobin adducts with 1,2,3,4‐diepoxybutane by liquid chromatography/electrospray ionisation mass spectrometry and matrix‐assisted laser desorption/ionisation tandem mass spectrometry
Authors: Basile Adriana , Ferranti Pasquale , Pocsfalvi Gabriella , Mamone Gianfranco , Miraglia Nadia , Caira Simonetta , Ambrosi Luigi , Soleo Leonardo , Sannolo Nicola , Malorni Antonio 
Published: September 2002

AbstractThe structural characterisation of the adducts formed by in vitro interaction of hemoglobin (Hb) with 1,2,3,4‐diepoxybutane (DEB), the most reactive 1,3‐butadiene (BD) metabolite, was obtained by liquid chromatography/electrospray ionisation mass spectrometry (LC/ES‐MS) analysis of modified tryptic peptides of human hemoglobin chains. The reactive sites of human hemoglobin towards DEB and its hydroxylated derivatives (trihydroxybutyl (THB)‐derivatives) were identified through the characterisation of alkylated tryptic peptides by matrix‐assisted laser desorption/ionisation tandem mass spectrometry (MALDI‐MS/MS). Based on this characterisation, a procedure was set up to measure the Hb‐adducts of THB‐derivatives by isotope dilution mass spectrometry with the use of a deuterated peptide standard. The results obtained here could permit optimisation of molecular dosimetry of BD‐adducts, and extension of the analysis to the biological monitoring of occupational exposure to butadiene. Copyright © 2001 John Wiley & Sons, Ltd.
Reactions of first‐row transition metal ions with propargyl alcohol in the gas phase
Authors: Zhao Xiang , Xin Bin , Xing Xiaopeng , Zhang Xia , Wang Guanghui , Gao Zhen 
Published: September 2002

AbstractThe gas‐phase reactions with propargyl alcohol (PPA) of all the singly charged ions of the first‐row transition metals, generated by laser ablation in an external ion source, were studied by Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICRMS.). The reactivities of the metal ions change irregularly across the periodic table, and the reactivity of each ion is a function of its electronic configuration and corresponding metal‐oxygen (M‐O) bond energies. The 10 metal ions were classified into three categories according to their reactivities: Sc+, Ti+ and V+ are the most reactive ions which react with PPA to give many kinds of oxygen‐rich products due to stronger M‐O bonds; Fe+, Co+ and Ni+ are less reactive; Cr+, Mn+, Cu+ and Zn+ are the most unreactive ions, due to the half and completely occupied valence electronic configurations. The order of reactivity is Ti+ > V+ > Sc+ ≫ Co+ > Fe+ ≈ Ni+ > Zn+ > Cr+ ≈ Mn+ ≈ Cu+. Copyright © 2001 John Wiley & Sons, Ltd.
A multi‐level satellite channel allocation algorithm for real‐time VBR data
Authors: Celandroni Nedo , Ferro Erina , Potortí Francesco 
Published: September 2002

AbstractIntegrated services over a shared satellite channel need a MAC protocol that is able to deal with real‐time traffic without substantially affecting the efficiency of the shared medium. Due to its bursty nature, MPEG coded VBR video transmission is one of the most challenging real‐time applications. In this paper, we analyse the statistical performance of a simple allocation method for VBR traffic by using an accurate statistical model of an MPEG‐2 VBR coded movie, whose traffic exhibits a peak to mean ratio of about 4. The results were obtained both analytically and by simulation, and show that our method is suitable for transmitting non‐interactive video and best‐effort traffic on the same satellite link. The efficiency of the proposed method shows no dependency on the statistical properties of the input traffic. Copyright © 2002 John Wiley & Sons, Ltd.
Initial growth of Au on oxides
Authors: Guo Qinlin , Luo Kai , Davis Kent A. , Goodman D. W. 
Published: September 2002

AbstractThe growth of Au clusters on TiO2(110)−(1 × 1) and −(1 × 2) single‐crystal surfaces and on ordered Al2O3 films prepared on Re(0001) has been studied by low‐energy electron diffraction (LEED), Auger electron spectroscopy (AES), low‐energy ion scattering spectroscopy (LEISS) and high‐resolution electron energy‐loss spectroscopy (HREELS). The results indicate that Au forms two‐dimensional islands on the TiO2(110) surface at initial deposition of Au. On the alumina film, Au initially grows as three‐dimensional clusters. The coverage of Au at which Au clusters change from non‐metallic to metallic properties is found to be >0.3 monolayer equivalent (MLE) of Au deposition based on the energy shift of the surface plasmon measurements. Copyright © 2001 John Wiley & Sons, Ltd.
Studies on the surface migration of adsorbed oxygen from noble metals to silver over binary catalysts
Authors: Huang W. X. , Teng J. W. , Bao X. H. 
Published: September 2002

AbstractAdsorbed oxygen migration from noble metals to silver was investigated on both an Ag/Pt(110) model catalyst and Al2O3‐supported Ag–Pd catalysts by photoelectron emission microscopy (PEEM) and oxygen temperature‐programmed desorption (TPD). On the CO‐precovered Ag/Pt(110) surface, oxygen was observed to diffuse from the Pt(110) surface to the Ag surface by PEEM. The diffusion of oxygen was coupled locally with a surface reaction of COad + Oad, giving rise to rapid propagation of the oxygen front. Migration of oxygen from the Pd surface to the Ag surface was proved also by oxygen TPD experiments on Al2O3‐supported Ag–Pd catalysts. Copyright © 2001 John Wiley & Sons, Ltd.
Adlayer structure of 1‐C18H37 SH molecules: scanning tunnelling microscopy study
Authors: Xu Qing‐Min , Wan Li‐Jun , Wang Chen , Bai Chun‐Li 
Published: September 2002

AbstractThe adlayer structure of 1‐octadecanethiol (1‐C18H37SH) is investigated by scanning tunnelling microscopy (STM) with bare and chemically (I and S) modified Pt/Ir tips. The molecules were observed to form a well‐ordered self‐assembly monolayer on highly oriented pyrolytic graphite. The alkyl chains of molecules were clearly imaged by bare tips. The S‐modified tip was found to be effective to reveal the structural details of thiol groups (SH). Based on the STM results and theoretical calculations, a model for a 1‐octadecanethiol adlayer is proposed. Copyright © 2001 John Wiley & Sons, Ltd.
Molecular organization of diolefinic compounds observed with scanning tunnelling microscopy
Authors: Wu Peng , Zeng Qing‐dao , Wang Chen , Bai Chun‐Li 
Published: September 2002

AbstractWe observed diolefinic molecules assembled on a graphite surface with submolecular resolution in ambient conditions using scanning tunnelling microscopy (STM) and discussed the arrangement of the molecules. Furthermore, the photopolymerization process was studied using STM. Copyright © 2001 John Wiley & Sons, Ltd.
Brain, eye, and face defects as a result of ectopic localization of Sonic hedgehog protein in the developing rostral neural tube
Authors: Nasrallah Ilya , Golden Jeffrey A. 
Published: September 2002

AbstractBackgroundNormal development of the face, eyes, and brain requires the coordinated expression of many genes. One gene that has been implicated in the development of each of these structures encodes the secreted protein, Sonic hedgehog (Shh). During central nervous system development, Shh is required for ventral specification along the entire neural axis. To further explore the role of Shh in chick brain and craniofacial development, we overexpressed Shh in the developing rostral neural tubeMethodsIn order to determine if Shh is sufficient to ventralize the forebrain, we localized ectopically recombinant Shh protein to the rostral neural tube of chick embryos. The resulting embryos were evaluated morphologically and by assaying gene expression.ResultsDisruption in normal gene expression patterns was observed with a reduction or loss in expression of genes normally expressed in the dorsal forebrain (wnt‐3a, wnt‐4, and Pax‐6) and expansion of ventrally expressed genes dorsally (HNF‐3β, Ptc). In addition to the genetic alterations observed in the neural tube, a craniofacial phenotype characterized by a reduction in many cranial neural crest‐derived structures was observed. The eyes of Shh‐treated embryos were also malformed. They were small with expansion of the retinal pigmented epithelium, enlarged optic stalks, and a reduction of neural retina.Discussion: The ectopic localization of recombinant Shh protein in the rostral neural tube resulted in severe craniofacial anomalies and alterations of gene expression predicted by other studies. The system employed appears to be a model for studying the embryogenesis of malformations that involve the brain, eyes, and face. Teratology 64:107–113, 2001. © 2001 Wiley‐Liss, Inc.
Pesticide residues and vertical integration in Florida strawberries and tomatoes
Authors: Kilmer Richard L. , Andre Anouk M. , Stevens Thomas J. 
Published: September 2002

AbstractGovernment regulations and consumer concern about pesticide residues in food may increase the costs of production and marketing for producers and processors associated with food safety risks. Vertical coordination is an economic response for mitigating the costs associated with uncertain pesticide residue levels. Data from a survey of Florida strawberry and tomato growers were used to test the hypothesis that vertical integration is associated with a lower mean and variance of pesticide residues. The results confirm a significant negative relationship between vertical integration and fungicide and insecticide residues in Florida strawberries and insecticides in Florida tomatoes. However, fungicides in tomatoes had the opposite effect. [Econ‐Lit citations: L220, L660] © 2001 John Wiley & Sons, Inc.
Invasive aspergillosis in haematological malignancies: Clinical findings and management for intensive chemotherapy completion
Authors: Nosari Annamaria , Oreste Pierluigi , Cairoli Roberto , Montillo Marco , Carrafiello Gianpaolo , Astolfi Alberto , Muti Giuliana , Marbello Laura , Tedeschi Alessandra , Magliano Enrico , Morra Enrica 
Published: September 2002

AbstractSixty‐one cases of Aspergillus infection (35 acute myeloid leukemia, 15 acute lymphoid leukemia, one myelodysplastic syndrome, two aplastic anemia, eight non‐Hodgkin's lymphoma) seen in our department between January 1989 and July 1999 were studied retrospectively to evaluate the clinical characteristics, to ascertain the factors that influenced the outcome from mycotic infections, and whether early diagnosis and prolonged therapy permitted completion of scheduled intensive chemotherapy and bone marrow transplantation (BMT) without fungal recurrence. The patients were divided into three diagnostic categories: proven aspergillosis (autoptic or histologic diagnosis) n = 39, probable aspergillosis (radiological diagnosis with positive microbiology) n = 9, and possible aspergillosis (radiological diagnosis alone) n = 13. In the same period among 675 acute leukemia patients the incidence of proven or probable aspergillosis was 7.1%. At onset of infection 92% of patients were neutropenic (< 0.5 × 109/L). The most frequent site of infection was the lung (90%); disseminated disease was present in 20 patients. Among 44 assessable patients, 12 (27%) failed to respond to early antifungal therapy and died. Thirty‐two patients were cured with antifungal treatment, three of five nonneutropenic with only itraconazole, the others with amphotericin B 1 mg/Kg/day with or without itraconazole subsequently or with liposomal amphotericin, Ambisome, if renal toxicity occurred. Twenty‐four of 29 neutropenic responders, all affected by acute leukemia, continued scheduled intensive chemotherapies. Pulmonary lobectomy was successfully combined with medical treatment in two cases before scheduled BMT. After infection nine patients were submitted to BMT (six allo, one marrow unrelated donor (MUD), two auto) with Ambisome or itraconazole as secondary prophylaxis without fungal relapse (follow‐up: 25–99 months). The median time from fungal infection to transplant was five months, range 3–10. Thirteen of 29 surviving patients had leukemia relapse, but only three (23%) of these showed also fungal infection recurrence. In conclusion, a high index of suspicion and careful clinical and radiological examinations are the key to identifying infected patients early and to programming the following therapeutic steps. Above all in leukemia patients, prompt and aggressive administration of antifungal agents seems to improve the outcome of invasive fungal disease and to permit intensive chemotherapy completion and transplant. Am. J. Hematol. 68:231–236, 2001. © 2001 Wiley‐Liss, Inc.