bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclic Voltammetric Study of the Oxidation of Catechols in the Presence of Cyanide Ion
Authors: Nematollahi Davood , Alimoradi Mohammad , Husain S. Waqif
Published: March 2004

Electrochemical oxidation of catechols has been studied in the presence of cyanide ion as nucleophile in aqueous solution, by means of cyclic voltammetry and controlled‐potential coulometry. The results indicate that the participation of catechols in the Michael reaction with cyanide ion to form the corresponding o‐dihydroxybenzonitrile. Based on an EC mechanism, the homogeneous rate constants were estimated by comparing the experimental cyclic voltammetric responses with the digital simulated results.
Catalytic Au Electrodes Based on SAMs of per(6‐deoxy‐6‐thio‐2,3‐di‐O‐methyl)‐β‐cyclodextrin
Authors: Chmurski Kazimierz , Koralewska Anna , Temeriusz Andrzej , Bilewicz Renata
Published: March 2004

A three‐step sequential self‐assembly procedure was applied in preparing gold electrodes modified in a stable and controlled way by a monolayer of thiolated β‐cyclodextrin (β‐CD), with methylene blue (MB) included in its cavity as the active component of the monolayer, and octanethiol as the nonelectroactive spacer blocking the electrode surface not occupied by β‐CD. MB acted as a mediator of electrons with respect to a solution soluble analyte, H2O2, and provided electrical contact between the electrode and solution resident enzyme, laccase, catalyzing reduction of oxygen to water.
Selective Electroanalytical Assay for Cysteine at a Boron Doped Diamond Electrode
Authors: Nekrassova Olga , Lawrence Nathan S. , Compton Richard G.
Published: March 2004

The electrochemical oxidation of the cysteine‐quinone adduct has been examined as a means of providing an electroanalytical cysteine specific detection protocol. The appliance of square‐wave voltammetry allowed 0.5 μM as a limit of detection. The effects of various biologically relevant interferences including other thiols were studied and found to present no change in the voltammetric profile. The practical applicability and efficiency of the methodology was probed through the determination of cysteine concentration in growth tissue medium.
Electrochemistry at High Pressures: A Review
Authors: Giovanelli Debora , Lawrence Nathan S. , Compton Richard G.
Published: March 2004

High pressure electrochemical studies are potentially dangerous and less immediately implemented than conventional investigations. Technical obstacles related to properties of the working electrode material, preparation of its surface, availability of suitable reference electrodes, and the need for specially designed high pressure equipment and cells may account for the relative lack of experimental data on electrochemistry at high pressures. However, despite the stringent requirements for system and equipment stability, significant developments have been made in recent years and the combination of electrochemical methods with high hydrostatic pressure has provided useful insights into the thermodynamics, kinetics, and other physico‐chemical characteristics of a wide range of redox reactions. In addition to fundamental information, high pressure electrochemistry has also lead to a better understanding of a variety of processes under non‐classical conditions with potential applications in today's industrial environment from extraction and electrosynthesis in supercritical fluids to measurement of the pH at the bottom of the ocean. The purpose of this article is to detail the experimental pressurizing apparatus for electroanalytical measurements at high pressures and to review the relevant literature on the effect of pressure on electrode processes and on the properties of aqueous electrolyte solutions.
Analysis, testing, and implementation of seismic isolation of buildings in Chile
Authors: De la Llera Juan C. , Lüders Carl , Leigh Patricio , Sady Henry
Published: March 2004

This article summarizes the work done by the authors in seismic isolation over the past six years in Chile. First, a general evaluation of the optimal values of the yield level of the isolation system is performed, focusing on the idea of, but not restricted to, the use of lead–rubber bearings. These optimal values are obtained for two performance objectives: to minimize the base shear in the superstructure and to control the isolator deformation. They were used in the design and construction of two important isolated buildings that are described herein; a short description of the more relevant aspects of the design and implementation of the isolation system in these two buildings is also presented. Furthermore, results from a long testing program conducted on more than 260 full‐size elastomeric isolators are summarized and discussed. It is shown that these experimental results enable the elastomeric compounds to be characterized quite accurately by testing reduced‐scale specimens with elastomer thickness identical to that used in the full‐size isolators. Also, results from isolator constitutive modeling, scragging, and creep in the short term are briefly discussed. Inelastic analyses were performed in the structures in order to evaluate realistic interstory drift and floor acceleration response reduction factors due to the isolation design used. It is shown that in spite of the isolation system, minor inelastic excursions of the primary structure are expected, leading to smaller drift and acceleration reduction factors than those obtained from assuming an elastic response of the superstructure. In any case, seismic isolation is shown to be a very competitive alternative, technically and economically, for building design in Chile. Although it may be difficult to extrapolate this experience to other environments, the results presented herein demonstrate that seismic isolation is a technique that can be effectively used to mitigate seismic hazards in developing countries. Copyright © 2004 John Wiley & Sons, Ltd.
Frequency domain modal analysis of earthquake input energy to highly damped passive control structures
Authors: Takewaki Izuru
Published: March 2004

A new complex modal analysis‐based method is developed in the frequency domain for efficient computation of the earthquake input energy to a highly damped linear elastic passive control structure. The input energy to the structure during an earthquake is an important measure of seismic demand. Because of generality and applicability to non‐linear structures, the earthquake input energy has usually been computed in the time domain. It is shown here that the formulation of the earthquake input energy in the frequency domain is essential for deriving a bound on the earthquake input energy for a class of ground motions and for understanding the robustness of passively controlled structures to disturbances with various frequency contents. From the viewpoint of computational efficiency, a modal analysis‐based method is developed. The importance of overdamped modes in the energy computation of specific non‐proportionally damped models is demonstrated by comparing the energy transfer functions and the displacement transfer functions. Through numerical examinations for four recorded ground motions, it is shown that the modal analysis‐based method in the frequency domain is very efficient in the computation of the earthquake input energy. Copyright © 2004 John Wiley & Sons, Ltd.
Evaluation of pounding countermeasures and serviceability of elevated bridges during seismic excitation using 3D modeling
Authors: Zhu Ping , Abe Masato , Fujino Yozo
Published: March 2004

This paper conducts elaborate analyses to evaluate the effectiveness of pounding countermeasures and the serviceability of elevated bridges subject to severe ground motions using detailed 3‐dimensional non‐linear modeling of an entire bridge structure system. A three‐span elevated steel bridge is selected for a case study. The peak and residual magnitude of gaps between girders and the maximum shear deformations of bearings are computed and used in the serviceability evaluation. The results show that under proper configurations the mitigation devices work effectively in reducing pounding actions in both the longitudinal and rotational directions. Copyright © 2004 John Wiley & Sons, Ltd.
Correlating measured and simulated dynamic responses of a tall building to long‐distance earthquakes
Authors: Pan Tso‐Chien , Brownjohn James M. W. , You Xu‐Ting
Published: March 2004

For almost a decade, a 66‐storey, 280m tall building in Singapore has been instrumented to monitor its dynamic responses to wind and seismic excitations. The dynamic characteristics of the tall building have been investigated via both the finite element method and the experimental modal analysis. The properties of the finite element model have been shown to correlate well with those derived from the data recorded during the ambient vibration tests. During the study period, 21 sets of earthquake ground motions have been recorded at the building site. The basement motions may be divided into three categories based on their predominant frequency components with respect to the building's fundamental frequency. The calibrated three‐dimensional finite element model is employed to simulate the seismic response of the tall building. Correlation analysis of the time histories between the recorded data and the simulated results has been carried out. The correlation analysis results show that the simulated dynamic response time histories match well with those of the recorded dynamic responses at the roof level. The results also show that the simulated maximum response at the roof level is close to the peak response recorded during the earthquakes. Copyright © 2004 John Wiley & Sons, Ltd.
Seismic performance of laminated timber frames with fiber‐reinforced joints
Authors: Kasal B. , Pospisil S. , Jirovsky I. , Heiduschke A. , Drdacky M. , Haller P.
Published: March 2004

A series of dynamic experiments was performed on two‐story glue‐laminated timber frames. The tests included sinusoidal sweeps in one direction, arbitrary signals simulating earthquake loads in two directions, and harmonic free vibration at the fundamental frequency. Two experimental frames were manufactured and tested: (1) a control with horizontal laminations and no reinforcement at joint areas, and (2) a new frame design with densified material in the joint area that was further reinforced by glass‐fiber composite material. Preliminary tests of scaled and full‐size beam‐to‐column connections were performed to obtain connection characteristics needed for subsequent analytical modeling. Copyright © 2004 John Wiley & Sons, Ltd.
Chemical composition of the essential oils of Lantana camara L. occurring in south China
Authors: Sundufu Abu James , Shoushan Huang
Published: March 2004

Steam‐distilled volatile oils from the leaves and ﬂowers of Lantana camara L. were analysed by GC and GC–MS. The oils are characterized by a high percentage of sesquiterpenes. The main components detected are germacrene D (15.85%), β‐caryophyllene (12.35%), α‐humulene (9.31%) and germacrene‐B (6.19%). 1,8‐Cineole (4.61%), an oxygenated monoterpene is also reported. The role of the essential oils and their isolates in insect pest control is mentioned. Copyright © 2004 John Wiley & Sons, Ltd.
Essential oil composition of Nepeta meyeri Benth. from Iran
Authors: Seﬁdkon F. , Shaabani A.
Published: March 2004

Water‐distilled volatile oil from the aerial parts of Nepeta meyeri Benth. was analysed by a combination of GC and GC–MS. Eighteen components were identiﬁed, constitut approximately 99.3% of the oil. The main constituents of the essential oil were 4aα‐7α‐7aβ‐nepetalactone (53.2%), 1,8‐cineole (29.3%) and camphor (4.1%). Copyright © 2004 John Wiley & Sons, Ltd.
Study of the mechanism of microwave‐assisted extraction of Mahonia bealei (Fort.) leaves and Chrysanthemum morifolium (Ramat.) petals
Authors: Gao Shan , Han Wei , Deng Xiu
Published: March 2004

A study of microwave‐assisted extraction (MAE) for berberine in Mahonia bealei (Fort.) was carried out with batch equipment, in order to investigate the mechanism of the extraction related to structural changes in the glands. The extracts were analysed by ultraviolet‐visible spectrophotometry at 347 nm. The parameters investigated were solvent types, the intensity of microwave energy and the process ratio (g/ml) of materials to solvent volume. The microwave‐assisted extraction of different moisture content of materials was developed and optimized by means of three‐factor and three‐level orthogonal designs. Electron and optical micrographs of M. bealei (Fort.) leaves and Chrysanthemum morifolium (Ramat.) petals showed that the mechanism of the extractions was related to structural changes in the plant cells. Copyright © 2004 John Wiley & Sons, Ltd.
Supercritical carbon dioxide extraction of 2‐acetyl‐1‐pyrroline and volatile components from pandan leaves
Authors: Laohakunjit Natta , Noomhorm Athapol
Published: March 2004

The ﬂavour of pandan (Pandanus amaryllifolius Roxb.) leaves was extracted by supercritical ﬂuid with CO2 (SC‐CO2) under different conditions of pressure, temperature and contact time to determine the yield of 2‐acetyl‐1‐pyrroline (ACPY) and various other components; 14 volatile compounds on the gas chromatogram were identiﬁed, and the predominant constituents were ACPY and 3‐methyl‐2(5H)‐furanone. The interaction of different conditions signiﬁcantly inﬂuenced the yield of ACPY and various volatile compounds. There is a potential for high yield of ACPY by SC‐CO2 at 200 bar, 500 °C and 20 min. The SDE–ether extract was found to have a very small amount of ACPY and an undesirable odour, as compared to the dark green ethanol extract, which contains a relatively larger quantity of ACPY and even more 3‐methyl‐2(5H)‐furanone. Although at least 34 new components were uncovered from SC‐CO2, SDE, and ethanol extraction, both ACPY and 3‐methyl‐2(5H)‐furanone were the components tentatively obtained by all three methods. Copyright © 2004 John Wiley & Sons, Ltd.
The essential oils of Cinnamomum rhyncophyllum Miq. as natural sources of benzyl benzoate, safrole and methyl (E)‐cinnamate
Authors: Jantan Ibrahim bin , Ayop Norsiha , Mohd Ali Nor Azah , Ahmad Abu Said , Yalvema Mira Febrina , Muhammad Kartiniwati , Azizi Azlina Razimahwati
Published: March 2004

The leaf, bark and wood oils of Cinnamomum rhyncophyllum Miq. were investigated by gas chromatography on two columns of different polarity, retention indices and GC–MS. The oils were composed mainly of phenylpropanoids and benzylic compounds. The leaf oil may be a potential natural source of benzyl benzoate, since it constituted up to 77% of the oil. Other compounds present in appreciable amounts in the oil were β‐phellandrene (6.3%) and methyl (E)‐cinnamate (4.2%). The bark and wood oils were found to possess compositional similarities with little variation in the levels of each component. Safrole (43.3–51.0%) and methyl (E)‐cinnamate (40.5–43.1%) were the major constituents in these oils. However, the bark oil could be distinguished from the wood oil by containing a higher concentration of benzyl benzoate. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of growing location of marjoram (Origanum majorana L.) samples by comparison of essential oil proﬁles
Authors: Novak Johannes , Pank Friedrich , Langbehn Jan , Blüthner Wolf‐Dieter , Vender Carla , Van Niekerk Léon , Junghanns Wolfram , Franz Chlodwig
Published: March 2004

A canonical discriminant function analysis (CDA) was applied to essential oil compounds proﬁles to determine the growing location of marjoram samples. 12/21 essential oil compounds were integrated into two discriminant functions as the best predictors for geographical differences. Stepwise integration allowed the determination of the essential oil compounds mainly responsible for the geographical variation, viz. myrcene, terpinene‐4‐ol, γ‐terpinene and p‐cymene. The two discriminant functions themselves showed a strong association between the locations and the predictors. The two functions allowed a correct classiﬁcation of 95% of samples (cross‐validated). The high positive classiﬁcation rate demonstrates the CDA's ability as a quality assurance tool enabling authenticity control. Copyright © 2004 John Wiley & Sons, Ltd.
Essential oils of Phlomis species growing in Greece: chemical composition and antimicrobial activity
Authors: Aligiannis N. , Kalpoutzakis E. , Kyriakopoulou I. , Mitaku S. , Chinou I. B.
Published: March 2004

The essential oils obtained from the aerial parts of Phlomis fruticosa, P. cretica and P. samia, growing in Greece, were analysed by GC and GC–MS. From the 72 identiﬁed constituents, representing 84.3%, 90.4% and 67.4% of the oils, respectively, α‐pinene, limonene, β‐caryophyllene, linalool, (E)‐β‐farnesene, germacrene D, (Z)‐γ‐bisabolene and cis‐β‐ocimene were the major components. Furthermore, all the oils exhibited an interesting antimicrobial proﬁle after they were tested against two Gram‐positive and four Gram‐negative bacteria and three pathogenic fungi. Copyright © 2004 John Wiley & Sons, Ltd.
Analysis of the volatile oil from Pilocarpus pennatifolius Lemmaire (Rutaceae) leaves by GC–MS
Authors: Santos Ana Paula , Lopes Melânia Cornélio , Limberger Renata P. , Apel Miriam Anders , Henriques Amélia T. , Moreno Paulo R. H.
Published: March 2004

The oil obtained by steam distillation of dried and powdered Pilocarpus pennatifolius Lemmaire leaves was analysed by GC and GC–MS. The major components were tridecane (56.7%) and pentadecane (25.5%). Additionally, γ‐muurolene (6.6%), spathulenol (2.6%), β‐elemene (2.1%), β‐caryophyllene (1.2%) and eugenol (0.3%) were also found in the crude oil. Copyright © 2004 John Wiley & Sons, Ltd.
Inﬂuence of drying methods on the essential oil content and composition of Roman chamomile
Authors: Omidbaigi R. , Seﬁdkon F. , Kazemi F.
Published: March 2004

The ﬂowers of Roman chamomile (Chamaemelum nobile L. All. var. ﬂora plena) cultivated in Iran were dried by three different drying methods of sun‐drying, shade‐drying and oven‐drying at 40 °C. The essential oils of every treatment were obtained by hydrodistillation of the ﬂowers, and were analysed by GC and GC–MS. The oil content of the shade‐dried ﬂowers was the largest (1.9% w/w) compared to sun‐drying (0.4% w/w) and oven‐drying at 40 °C (0.9% w/w). Drying methods had no effect on the number of chemical components of the essential oil, as 14 components were identiﬁed in the oil of every drying method. The major components were isobutyl angelate, 2‐methyl butyl angelate, propyl tiglate, isoamyl angelate and 3‐methylbutyl isobutyrate. However, the drying method had a signiﬁcant effect on the proportion of the various components. Copyright © 2004 John Wiley & Sons, Ltd.
The effect of high hydrostatic pressure on anthocyanins and ascorbic acid in blackcurrants (Ribes nigrum)
Authors: Kouniaki Soﬁa , Kajda Paul , Zabetakis Ioannis
Published: March 2004

The stability of two anthocyanins and ascorbic acid present in fruit juices made from blackcurrants that were subjected to high‐pressure processing (HHP) was studied. HHP is a non‐thermal food preservation method and its impact on the nutritionally important anthocyanins, cyanidin‐3‐rutinoside, delphinidin‐3‐rutinoside and also ascorbic acid (vitamin C), in blackcurrants was assessed. Fruit samples were treated at 200, 400, 600 and 800 MPa for 15 min under controlled temperature (20–22.5 °C). After high‐pressure treatment the samples were stored at fridge temperature (5 °C), room temperature (20 °C) and at 30 °C. The analysis of the anthocyanin and ascorbic acid contents were carried out by using high performance liquid chromatography (HPLC). The best stability for cyanidin‐3‐rutinoside pigment was found when blackcurrants were treated at a HP of 600 MPa and were stored at 5 °C. Delphinidin‐3‐rutinoside had the lowest losses when treated at 800 MPa and stored at 5 °C. High pressure at 600 MPa gave the best preservation for all the samples stored at 5 °C and 20 °C. The rates of losses observed for anthocyanins were linked to those observed for the ascorbic acid and these results are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Comparison of three sample preparation methods on the recovery of volatiles from taheebo (Tabebuia impetiginosa Martius ex DC)
Authors: Park Byeoung‐Soo , Lee Kwang‐Geun , Takeoka Gary R.
Published: March 2004

The volatile constituents of taheebo (the dried inner bark of Tabebuia impetiginosa Martius ex DC) were isolated by three methods: solvent‐assisted ﬂavour evaporation (SAFE); steam distillation under reduced pressure, followed by continuous liquid–liquid extraction (DRP‐LLE); and high‐ﬂow dynamic headspace sampling (including closed‐loop stripping) (DHS). The extracts were analysed qualitatively and quantitatively by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). The masses of total volatile components recovered from 50 g taheebo by SAFE, DRP‐LLE and DHS were 26.3 ± 2.0, 19.4 ± 1.0 and 1.2 ± 0.2 mg, respectively. The major constituents isolated with the SAFE method were 4‐methoxyphenol (121.65 µg/g), 4‐methoxybenzyl alcohol (96.49 µg/g), 1,2‐propanediol (92.95 µg/g) and 4‐methoxybenzaldehyde (31.33 µg/g). The DRP‐LLC method yielded 4‐methoxybenzaldehyde (64.54 µg/g), 4‐methoxyphenol (42.30 µg/g), 5‐(2‐propenyl)‐1,2,3‐trimethoxybenzene (elemicin; 41.22 µg/g), and 1‐methoxy‐4‐(1E)‐1‐propenylbenzene (trans‐anethole; 39.16 µg/g) as major volatiles, while the main compounds recovered with the DHS method were 4‐methoxybenzaldehyde (2.61 µg/g), 4‐methoxyphenol (2.10 µg/g), 2‐methyl‐5‐(1‐methylethenyl)‐2‐cyclohexen‐1‐one (carvone; 1.71 µg/g) and 3,7‐dimethyl‐1,6‐octadien‐3‐ol (linalool; 1.64 µg/g). Copyright © 2004 John Wiley & Sons, Ltd.
Aroma compounds of some Hyblean pasture species
Authors: Carpino S. , Mallia S. , Licitra G. , Van Soest P. J. , Acree T. E.
Published: March 2004

The Hyblean pastures are characterized by a great variety of native forages, and offering opportunity for selective feeding by animals. Over 100 plant species belonging to over 25 families occur, although not all of these may occur in single pasture.1 The occurrence of pasture species and the selective forage behaviour of dairy cattle in very complex pastures was part of a larger study on the inﬂuence of diet upon cheese ﬂavour. The plant diversity may contribute to cheese ﬂavour.2 The animals were individually followed on the pasture and the kind of species and plant parts selected were recorded.3 The volatile constituents of the above‐ground (aerial) parts of the most commonly occurring and selected plant species in the Hyblean pasture were extracted by steam distillation and analysed by GC–olfactometry (GC–O) and GC–MS. The number of odour‐active compounds identiﬁed in the plants ranged from 12 in Sinapis to 26 in Erodium. Copyright © 2004 John Wiley & Sons, Ltd.
Regions syntenic to human 17q are gained in mouse and rat neuroblastoma
Authors: Łastowska Maria , Chung Yeun‐Jun , Cheng Ching Ngan , Haber Michelle , Norris Murray D. , Kees Ursula R. , Pearson Andrew D. J. , Jackson Michael S.
Published: March 2004

Gain of chromosome arm 17q is the most frequent chromosomal change in human neuroblastoma and is a powerful predictor of adverse outcome of disease. This suggests that the region of gain includes a gene or genes critical for tumor pathogenesis. Analyses of breakpoint positions have revealed that the shortest region of gain (SRG) extends from MPO (17q23.1) to 17qter. Because this encompasses >300 genes, it precludes the identification of candidate genes from human breakpoint data alone. However, mouse chromosome 11, which is syntenic to human chromosome 17, is gained in up to 30% of neuroblastoma tumors developed in a murine MYCN transgenic model of this disease. To confirm that this key genetic change indicates the involvement of a molecular pathway conserved between mouse and man and is not occurring coincidentally in the transgenic model, we used fluorescence in situ hybridization to analyze sporadic cases of both mouse and rat neuroblastoma. Our results confirmed the presence of chromosome 11 gain in all three of the mouse cell lines we analyzed, with the SRG extending from Stat5b (101.6 Mb) to tel. In addition, the rat neuroblastoma cell line harbors an extra copy of distal chromosome 10, extending from 92.8 to 109.3 Mb, which is also syntenic to human 17q. Comparison of the regions gained in all three species has excluded 4.2 Mb from the previously defined region of 17q gain in humans as a likely location of the candidate gene or genes, and strongly suggests that the molecular etiology of neuroblastoma is similar in all three species. © 2004 Wiley‐Liss, Inc.
Modelling non‐demanders in choice experiments
Authors: Ryan Mandy , Skåtun Diane
Published: April 2004

Discrete choice experiments have the advantage that they can study preferences in health care where revealed preference data is not readily available. However, as a substitute for actual observed market led data, the experimental set‐up for hypothetical situations must mimic the circumstances under which actual choices are made. One situation that a consumer/patient might face is an opt‐out option. They might not choose to accept any of the positive actions available and as such will be a non‐demander of the health care on offer. This paper explores issues raised in the modelling of such data within an experiment looking at women's preferences for cervical screening services. Copyright © 2003 John Wiley & Sons, Ltd.
P/Q Ca2+ channel blockade stops spreading depression and related pyramidal neuronal Ca2+ rise in hippocampal organ culture
Authors: Kunkler Phillip E. , Kraig Richard P.
Published: March 2004

Ca2+ channels and pyramidal cell Ca2+ are involved in hippocampal spreading depression (SD), but their roles remain elusive. Accordingly, we characterized Ca2+ changes during SD in CA3 pyramidal neurons and determined whether Ca2+ channel antagonists could prevent SD. SD was induced in hippocampal organotypic cultures (HOTCs), in which experimental conditions can be rigorously controlled. SD was triggered by transient exposure to sodium acetate (NaAc)‐based Ringer's coupled to an electrical pulse in the dentate gyrus and its occurrence confirmed with interstitial DC recordings. Pyramidal cell Ca2+ was measured with fura‐2 filled cells and was quantified at the soma, proximal and more distal apical dendrites. Regional Ca2+ changes began simultaneously with the triggering pulse of SD and reached three distinct peaks before returning to baseline concomitant with the interstitial DC potential of SD. The first peak occurred within 5 s of the triggering pulse, was smallest, and heralded the onset of SD. The second Ca2+ change was the greatest and reached a peak 6 s later, during the early phase of SD. The third was intermediate in size and occurred 18 s later, as SD reached its maximum interstitial DC change. SD was prevented by nonselective Ca2+ blockade (Ni2+ and Cd2+) but not by either L‐Ca2+ channel (nifedipine) or N‐Ca2+ channel inhibition (ω‐conotoxin GVIA). Importantly, SD was blocked by P/Q Ca2+ channel antagonism (ω‐agatoxin‐IVA), which also prompted a significant reduction in pyramidal cell Ca2+ change and hyperexcitability. These results show that the spatiotemporal pattern of pyramidal cell Ca2+ change with SD is multiphasic; they provide further evidence that these changes begin before electrophysiologic evidence of SD. Furthermore, they show that P/Q Ca2+ channel antagonism can prevent SD in HOTCs and it appears to do so by preventing the NaAc‐induced increased pyramidal cell excitability from NaAc exposure, which may involve altered GABAergic transmission. © 2003 Wiley‐Liss, Inc.
Effect of field groundwater table control on water and salinity balance and crop yield in the Qingtongxia Irrigation District, China
Authors: Wang Xiugui , Hollanders P. H. J. , Wang Shaoli , Fang Shuxing
Published: March 2004

The Qingtongxia Irrigation District (QID) is one of the key agricultural bases in the Yellow River Basin. It is located in the upstream part of the Yellow River in the north of China and covers about 350 000 ha of farmland. The climate in the district is arid and semi‐arid. The annual average precipitation is about 200 mm. Water shortage is one of the main restrictions on agricultural development. In recent years, large amounts of water have been drawn from the Yellow River, which not only contributes to the severity of water shortages in the middle and downstream part of the Yellow River Basin, but also leads to the rise of the groundwater table and related waterlogging and salinization of the farmland.

This article focuses on the analysis of the effects of field groundwater table control under different irrigation water amounts on the soil water and salinity content and on relative crop yield. Two experimental areas, Pingluo and Huinong, were selected to collect the required field data. The agro‐hydrological model SWAP was used to analyse the water flow and salt transport for different groundwater table and irrigation scenarios. Six scenarios, which resulted from two groundwater table regimes combined with three irrigation amounts, were simulated. The groundwater table regimes represent the present and future target groundwater table situation and the three irrigation amounts represent different water‐saving options. Waterlogged land is also simulated. The results show that:

High regional groundwater tables are the main reason for the large amount of drainage water and low crop yield.

Due to the regional high groundwater table, reducing irrigation amounts in the field without lowering the field groundwater table will not lead to a large reduction of drainage water, and will cause a further reduction in crop yield.

The salinity storage in the soil profile at the end of the growing season will increase when the irrigation amount is reduced, and when the groundwater table is lower. But the increase is very small.

To lower the field groundwater to the target water table is an effective way to increase crop yield. Copyright © 2004 John Wiley & Sons, Ltd.
Global warming and drainage development: perspective and challenges
Authors: Wrachien Daniele De , Feddes Reinder
Published: March 2004

Irrigated agriculture is expected to play a major role in reaching the broader development objectives of achieving food security and improvements in the quality of life, while conserving the environment, in both the developed and developing countries. Especially as we are faced with the prospect of global population growth from almost 6 billion today to at least 8 billion by 2025. In this context, the constraints posed by land and water scarcity and the associated need to increase the carrying capacity of the land in a sustainable manner will require significant enhancements in efficiency and flexibility of irrigation and drainage systems in the next few decades.

In most of the world's irrigated and rainfed lands, drainage facilities were developed on a step‐by‐step basis over the centuries. In many facilities structures have aged or are deteriorating and, consequently, they need to be renewed or even replaced and thus, redesigned and rebuilt. In the past, drainage systems were designed for a long life, on the assumption that climatic conditions would not change in the future. This will not be so in the years to come, due to global warming and the greenhouse effect. Therefore, planners and designers need to systematically re‐examine planning principles, design criteria, operating rules and management policies for new infrastructures.

In relation to these issues and based on available information, the report gives an overview of current and future (time horizon 2025) drainage developments around the world. Moreover, the paper analyses the results of four of the most advanced global circulation models for assessing the hydrological impact of global warming, due to the greenhouse effect, on the drainage planning and design process. Finally, a five‐step planning and design procedure is proposed, able to integrate, within the development process, the hydrological consequences of climate change. Copyright © 2004 John Wiley & Sons, Ltd.
Differential expression of transforming growth factor‐β in the interstitial tissue of testis during aging
Authors: Jung Jae‐Chang , Park Geun‐Tae , Kim Kook‐Hee , Hyung Woo Ju , An Jung‐Min , Kim Ki‐Chul , Young Chung Hae , Bae Young‐Seuk , Woo Park Jeen , Kang Shin‐Sung , Lee Young‐Sup
Published: April 2004

Transforming growth factor‐βs (TGF‐βs) have significant effects on testis development. The pattern of TGF‐β expression in aging testis has not been established to date. We examined age‐related changes in the expression of TGF‐β and its receptors in the testis using Western blot analysis. TGF‐β1 expression increased continuously in aging rat testis, whereas no age‐associated changes were observed for TGF‐β3. Strong expression of TGF‐β2, as well as type I and II receptors was observed in 12‐month‐old testis, but following this time, expression decreased dramatically. Interestingly, TGF‐β2 and ‐β3 displayed strong and similar expression patterns in liver, regardless of age, suggesting that the down‐regulation of TGF‐β2 is testis‐specific. We observed significant induction of p53 and p21WAF1 in 18‐month‐old testis that appeared to correspond with aging. Moreover, caloric restriction (CR) prevented age‐related decrease in TGF‐β2 expression. Using immunohistochemistry, we showed that all TGF‐β1, ‐β2, and ‐β3 proteins are expressed primarily in interstitial cells, which are located in the space between adjoining seminiferous tubules. Our data collectively indicate that aging in the testis is regulated by differential expression of TGF‐β proteins, and decreased levels of TGF‐β2 contribute to the aging process. © 2004 Wiley‐Liss, Inc.
A theoretical study of structures and electron affinities of radical anions of guanine‐cytosine, adenine‐thymine, and hypoxanthine‐cytosine base pairs
Authors: Kumar Anil , Knapp–Mohammady Michaela , Mishra P. C. , Suhai Sándor
Published: March 2004

Adiabatic electron affinities (AEA) and structural perturbations due to addition of an excess electron to each of the neutral guanine‐cytosine (G‐C), adenine‐thymine (A‐T), and hypoxanthine‐cytosine (HX‐C) base pairs were studied using the self‐consistent charge, density functional tight‐binding (SCC‐DFTB‐D) method, augmented by the empirical London dispersion energy term. Performance of the SCC‐DFTB‐D method was examined by comparing the calculated results using it with those obtained from experiment as well as ab initio and other different density functional theoretical studies. An excellent agreement between the SCC‐DFTB‐D results and those obtained by the other calculations regarding the structural modifications, hydrogen bonding, and dissociation energies of the neutral and radical anion base pairs was found. It is shown that adiabatic electron affinity can be better predicted by considering reaction enthalpies of formation of the respective neutral and anionic base pairs from their respective molecular components instead of taking the difference between their total energies. The calculated AEAs of the base pairs were compared with those obtained by the bracketing method from Schaefer and coworkers, where a satisfactory agreement was found. It shows applicability of the SCC‐DFTB‐D method to study charged DNA models at a highly economical computational cost. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1047–1059, 2004
Separation of adult chains of abnormal haemoglobin: Identification by reversed‐phase high‐performance liquid chromatography
Authors: Yapo Paul Angoué , Datté Jacques Y. , Yapo Ayekoé , Wachman Henri
Published: March 2004

Rare abnormal haemoglobin (Hb) often poses a problem in the diagnosis of relative electrophoresis mobility. The rare neutral Hbs interact with the Hb S and thus can increase the severity of sickle cell anaemia. In the present study, we investigated the use of reversed‐phase high‐performance liquid chromatography (RP‐HPLC) as a method for the identification of neutral or unstable Hb, and compared it with the well‐known techniques urea‐triton electrophoresis (UT) and isoelectrofocusing (IEF). The results of our experiments showed that Bucuresti Hb was separated without ambiguity by RP‐HPLC. To date, no other electrophoresis techniques have been able to isolate this Hb. We also examined the Hb Nouakchott, which was the most hydrophobic Hb. Moreover, the adult and foetal chains of globins (especially the Aγt and Aγi chains) were quantified on the same chromatogram. J. Clin. Lab. Anal. 18:65–69, 2004. © 2004 Wiley‐Liss, Inc.
A pathologist's perspective on bone marrow aspiration and biopsy: I. performing a bone marrow examination
Authors: Riley Roger S. , Hogan Thomas F. , Pavot Dawn R. , Forysthe Robert , Massey Davis , Smith Eileen , Wright Lou , Ben‐Ezra Jonathan M.
Published: March 2004

The bone marrow aspirate and biopsy is an important medical procedure for the diagnosis of hematologic malignancies and other diseases, and for the follow‐up evaluation of patients undergoing chemotherapy, bone marrow transplantation, and other forms of medical therapy. During the procedure, liquid bone marrow is aspirated from the posterior iliac crest or sternum with a special needle, smeared on glass microscope slides by one of several techniques, and stained by the Wright‐Giemsa or other techniques for micro‐scopic examination. The bone marrow core biopsy is obtained from the posterior iliac crest with a Jamshidi or similar needle and processed in the same manner as other surgical specimens. Flow cytometric examination, cytochemical stains, cytogenetic and molecular analysis, and other diagnostic procedures can be performed on bone marrow aspirate material, while sections prepared from the bone marrow biopsy can be stained by the immunoperoxidase or other techniques. The bone marrow procedure can be performed with a minimum of discomfort to the patient if adequate local anesthesia is utilized. Pain, bleeding, and infection are rare complications of the bone marrow procedure performed at the posterior iliac crest, while death from cardiac tamponade has rarely occurred from the sternal bone marrow aspiration. The recent development of bone marrow biopsy needles with specially sharpened cutting edges and core‐securing devices has reduced the discomfort of the procedure and improved the quality of the specimens obtained. J. Clin. Lab. Anal. 18:70‐90, 2004. © 2004 Wiley‐Liss, Inc.
Novel point mutation in exon 12 of the glucose‐6‐ Phosphate Dehydrogenase Gene: G6PD Flores
Authors: Rodrigues Maria‐Odete , Pereira Júlia Dias , Gaspar Gisela , Olim Gabriel , Martins Maria‐do‐Carmo , Monteiro Carolino
Published: March 2004

In Portugal there are a wide variety of G6PD deficiency associated mutations. In an individual from the island of Flores of the Azorean archipelago, we report a new mutation in the G6PD gene that gives rise to a “moderate rate of G6PD deficiency” (12.6% of the normal activity) according to WHO criteria. Direct sequencing revealed a C→A point mutation at position 1387 with the consequent substitution of an Argine by Serine. We designated this new mutation as G6PD FLORES. The mutation is associated with haplotype I ( – – + + – – ), using six intragenic RFLPs. This information may also be seen as contributing to the clarification of the genetic makeup of the Azorean population, founder mutations, and/or gene flow. J. Clin. Lab. Anal. 18:129–131, 2004. © 2004 Wiley‐Liss, Inc.
Reference distributions for α2‐macroglobulin: A comparison of a large cohort to the world's literature
Authors: Ritchie Robert F. , Palomaki Glenn E. , Neveux Louis M. , Navolotskaia Olga
Published: March 2004

The lack of satisfactory methods for quantifying serum levels and a credible reference material has limited bedside use of serum alpha2‐macroglobulin (α2M) measurements. Great strides have been made in the last few years. The remaining barrier to more relevant and cost effective use of serum protein data for diagnosis and prognosis is the availability of reliable reference intervals from birth to old age for both males and females. A total of 40 publications reporting reference intervals have been identified that meet the criteria used in our prior five studies, and these have been analyzed statistically. On average, previous small studies of these individual proteins agree with our life‐long reference ranges over their constrained age ranges. This meta‐analysis provides support for our reference ranges and places them in the perspective of previous publications. J. Clin. Lab. Anal. 18:148–152, 2004. © 2004 Wiley‐Liss, Inc.
Clinical value of serum cystatin C by ELISA for estimation of glomerular filtration rate
Authors: Xu Xunhui , Zou Jianzhou , Ding Xiaoqiang , Xin Dingguang , Ren Yushen
Published: March 2004

The search for whether endogenous markers of changes in glomerular filtration rate (GFR) by serum cystatin C assay and serum cystatin C compare with creatinine clearance by the Cockeroft‐Gault formula and the evaluation of its clinical significance as a marker of GFR is important in clinical practice at present. Serum cystatin C was determined by sandwich enzyme immunoassay using a kit. Control blood samples were collected from 70 healthy subjects and 168 patients with various kidney diseases. Creatinine clearance (Cockeroft‐Gault formula) as a measure of GFR, in 168 patients with various kidney diseases, depends on the creatinine clearance; GFR parameters were used to divide patients into two groups. The GFR was >80 mL/min in 38 patients (group A) and <80 mL/min in 130 patients (group B). The two groups were analyzed by correlation coefficient and diagnostic sensitivity and specificity were assessed by the receiver‐operating characteristic (ROC) plots (area under the curve). Of the 70 healthy control individuals, the serum level of cystatin C was measured as normal value range and a reference interval of 1.05±0.18 µg/mL (mean±1.96 SD, 95% confidence limits for the upper references limit is 1.4 μg/mL). In group A, serum cystatin C had no correlation to the creatinine clearance (r=0.171, P>0.05) and in group B, serum cystatin C was closely correlated to the creatinine clearance (r=−0.771, P<0.001). Diagnostic sensitivity and specificity were assessed by the ROC plots for serum cystatin C (area under the curve=0.8461, SE=0.057) and creatinine clearance (area under the curve=0.7642, SE=0.068). These data suggest that combined measurement of serum cystatin C is useful to estimate GFR, especially to detect the reduction of GFR. Further studies are required to evaluate the whether serum cystatin C as a more sensitive marker of early renal injury might be extremely useful, particularly in nonproteinuric or unapparent renal disease. J. Clin. Lab. Anal. 18:61–64, 2004. © 2004 Wiley‐Liss, Inc.
Does television influence adolescents' perceptions of and attitudes toward people with mental illness?
Authors: Minnebo Jurgen , Van Acker An
Published: April 2004

This study investigates whether and how (1) cumulative overall exposure to television and (2) cumulative selective exposure to specific television content are related to both estimates of and opinions about people who have mental illnesses. Two hundred fifty‐two Belgian high school students completed self‐report questionnaires. Measures included time spent watching television, exposure to specific content, perceived realism of television images, direct experience with a person who had mental illness, and estimates of and judgements about the dangerousness of people suffering from a mental illness and their ability to lead a socially integrated and “normal” life. Results suggest exposure to television itself makes but a small contribution to explaining these estimates and attitudes; related concepts such as perceived realism appear to be more important. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 257–275, 2004.
Urban adolescents' perceptions of their neighborhoods: An examination of spatial dependence
Authors: Bass Judith K. , Lambert Sharon F.
Published: April 2004

Spatial dependence exists when the variation between observations is dependent on spatial location. In the present study, geostatistical methods were used to examine spatial dependence in adolescents' perceptions of their neighborhoods: whether adolescents living in close proximity perceived their neighborhoods more similarly than adolescents living further apart. Participants included 343 adolescents (53% male; 91% African American) enrolled in sixth grade, residing in Baltimore City, with geocoded home addresses. These addresses were used in combination with a measure of perceived neighborhood disorder and disadvantage to compute variogram plots, a geostatistical technique used to evaluate spatial dependence. Results indicated that perceptions of youth residing in close geographic proximity were more similar than perceptions of youth residing further apart. Adjusting for census‐level characteristics, but not individual and family characteristics, resulted in decreased variation among participants but did not eliminate the spatial dependence. Findings highlight the utility of geostatistical methods for social science research. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 277–293, 2004.
RNA‐containing adenovirus/polyethylenimine transfer complexes effectively transduce dendritic cells and induce antigen‐specific T cell responses
Authors: Gust Tatjana C. , Diebold Sandra S. , Cotten Matt , Zenke Martin
Published: March 2004

Background

Dendritic cells (DCs) are the most potent antigen‐presenting cells in initiating primary immune responses. Given the unique properties of DCs, gene‐modified DCs represent a particularly attractive approach for immunotherapy of diseases such as cancer.

Methods

Gene‐modified DCs were obtained by a receptor‐mediated gene delivery system using adenovirus (Ad) particles as ligand and RNA or DNA condensed by polyethylenimine (PEI). In vitro transcribed polyadenylated or non‐polyadenylated RNA was used. RNA‐transduced DCs were generated expressing chicken ovalbumin (OVA) or chimeric constructs thereof, and compared with DNA‐transduced DCs.

Results

Ad/PEI transfection complexes efficiently delivered RNA into DCs. Such RNA‐transduced DCs induced OVA‐specific T cell responses more effectively than DNA‐transduced DCs. Furthermore, DCs transduced with polyadenylated RNA were more potent in stimulating CD4+ and CD8+ T cell responses than DCs transduced with non‐polyadenylated RNA and this was particularly important for CD4+ T cell responses.

Conclusions

Ad/PEI/RNA transfection is an efficient means for generating RNA‐transduced DCs and for stimulating antigen‐specific T cell responses. Polyadenylation of RNA enhances CD8+ T cell responses and is essential for CD4+ T cell responses. Copyright © 2004 John Wiley & Sons, Ltd.