bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of electrical and optical properties of silicon nanoclusters using flicker‐noise spectroscopy
Authors: Parkhutik V. , Duart J. M. Martínez
Published: September 2002

This paper presents the results of a study on the electrical properties, chemical composition and photoluminescence from silicon nanocrystals produced by electrochemical etching of silicon wafers. A new phenomenological tool, known as flicker‐noise spectroscopy (FNS), was used to analyze the experimental data. The electrical and optical signals from silicon nanoclusters are quite noisy. We show that FNS can be applied efficiently in analysis of these signals, allowing one to obtain significant information on the nature of dynamic microscopic processes assisting the flow of the electric current and emission of light from silicon clusters. The FNS method is also suitable for resolving the problem of the irreproducibility of the properties of nanostructured materials and devices. Deviations in size, local chemical impurities, structural defects and other micro‐inhomogeneities strongly influence the output signals from nanostructures and make their characteristics poorly reproducible. The FNS approach makes it possible to scale the output information from nanostructured devices to a level where these deviations and irreproducibilities are no longer important. Copyright © 2001 John Wiley & Sons, Ltd.
Hydrolysis and chemical speciation of (C2H5)2Sn2+, (C2H5)3Sn+ and (C3H7)3Sn+ in aqueous media simulating the major composition of natural waters
Authors: Foti Claudia , Gianguzza Antonio , Milea Demetrio , Sammartano Silvio
Published: September 2002

The hydrolysis of (C2H5)2Sn2+, (C2H5)3Sn+ and (n‐C3H7)3Sn+ has been studied, by potentiometric measurements ([H+]‐glass electrode), in NaNO3, NaCl, NaCl/Na2SO4 mixtures and in a synthetic seawater (SSWE), as an ionic medium simulating the major composition of natural seawater, at different ionic strengths (0 ≤ I ≤ 5 mol dm−3) and salinities (15 ≤ S ≤ 45), and at t = 25 °C. Five hydrolytic species for (C2H5)2Sn2+, three for (C2H5)3Sn+ and two for (C3H7)3Sn+ are found. Interactions with the anion components of SSWE, considered as single‐salt seawater, are determined by means of a complex formation model. A predictive equation for the calculation of unknown hydrolysis constants of trialkyltin(IV) cations, such as tributyltin(IV), in NaNO3, NaCl, and SSWE media at different ionic strengths is proposed. Equilibrium constants obtained are also used to determine the interaction parameters of Pitzer equations. Copyright © 2001 John Wiley & Sons, Ltd.
Microvascular architecture of the rat choroid: Corrosion cast study
Authors: Bhutto Imran Ahmed , Amemiya Tsugio
Published: September 2002

This study presents the details of the microvasculature of the rat choroid visualized by scanning electron microscopy of vascular corrosion casts. Wistar Kyoto rats were anesthetized with intraperitoneal sodium pentobarbital. The vascular system was perfused with heparinized saline, and Mercox resin was injected into the cannulated carotid arteries. After polymerization of the resin, the vascular casts were macerated with potassium hydroxide, washed with water, and freeze dried. The casts were examined with a Hitachi S‐2360N scanning electron microscope (SEM). Corrosion casts of the entire choroidal vasculature revealed that the two long posterior ciliary arteries supplied the entire uveal vasculature. In the posterior choroid, these arteries formed five to seven branches on each side supplying the adjacent choriocapillaris. No interarterial or arteriovenous anastomoses were seen. The choriocapillaris appeared as a nonhomogeneous and nonlobular monolayer capillary network, consisting of dense honeycomb and irregular patterns. There are two distinct venous systems in the rat choroid. The venous blood from the central region, peripapillary choroid, and sometimes the optic nerve head drain into the posterior ciliary vein. The venous blood from the iris, ciliary body, anterior choroid, and half of the posterior choroid drain into the vortex veins. Corrosion casts and the SEM have shown details of the choroidal vascular architecture. These three‐dimensional observations indicate that the rat choroidal vasculature has different features from those of humans and other primates. Despite these interspecies differences, the establishment of a thorough baseline concept of choroidal vasculature should permit additional studies of the choroidal pathology and enable the proper interpretation of results from rat experimental models for extrapolation to humans. Anat Rec 264:63–71, 2001. © 2001 Wiley‐Liss, Inc.
Characterization and functions of the whitefly egg pedicel
Authors: Buckner James S. , Freeman Thomas P. , Ruud Rita L. , Chu Chang‐chi , Henneberry Thomas J.
Published: September 2002

For the silverleaf whitefly, Bemisia argentifolii (Bellows and Perring) (Homoptera: Aleyrodidae), scanning and transmission electron microscopic techniques were used to observe the characteristics of egg oviposition into both plant cells/tissues and artificial membranes, and to document the morphology of mature egg pedicles removed from the ovaries of females. The exterior of the distal portion of the pedicel consisted of a tangled array of fibrous structures (0.2–0.3 μm in diameter) that constituted about 20–25% of the outer diameter of the pedicel. The attachments of the fibers to the core of the pedicle suggested that the pedicel functions as the collector and conduit for water (vapor), and perhaps solute movement into the egg. Silverleaf whitefly eggs on membranes were incubated at various levels of relative humidity and the eggs were scored for egg hatch. At 98–100% rh, the percentage egg hatch was 86–98%. At lower humidity ranges of 0–20, 55–65, and 75–85% rh, none of the eggs hatched. Media (solute) uptake by silverleaf whitefly egg pedicels was determined by exposing the pedicel side of eggs oviposited on membranes to media solutions containing the high molecular weight polysaccharide, [14C]‐inulin. Solute uptake by the pedicel and movement into developing silverleaf whitefly eggs were demonstrated using [2‐14C]‐acetate, and assaying for radioactivity in hatched nymphs. These studies, using exposure of pedicels to relative humidity and radiolabeled materials, demonstrate that whitefly egg hatch is dependent upon water uptake by the pedicel, and that the pedicel has the ability to transport solutes into the developing egg. Arch. Insect Biochem. Physiol. 49:22–33, 2002. Published 2002 Wiley‐Liss, Inc.
Synthesis of lipids in the fat body of Gryllus bimaculatus: Age‐dependency and regulation by adipokinetic hormone
Authors: Lorenz Matthias W.
Published: September 2002

The free abdominal fat body of adult female Mediterranean field crickets, Gryllus bimaculatus, synthesizes lipids from [1‐14C]‐acetate in vitro. Up to an age of 12�h, the incorporation of acetate into lipids is very low and then rises to a maximum 24�h after adult emergence. Thereafter, the incorporation of acetate decreases to moderate levels at day 2 and then slowly decreases until day 30. The adipokinetic hormone of G. bimaculatus (Grb‐AKH) significantly inhibits the incorporation of acetate at a concentration of 10–11 M; maximum inhibition (approximately 95%) is reached at 10–8 M. The inhibiting effect of Grb‐AKH is fast, dose‐dependent, and reversible. The periovaric fat body shows a similar pattern of acetate incorporation, although rates of incorporation are lower; the incorporation can be inhibited by Grb‐AKH as well. The segmental abdominal fat body and the fat body from the head both incorporate acetate into lipids at low rates that cannot be inhibited significantly by AKH. Prepurified brain extracts significantly inhibit acetate incorporation by free abdominal fat bodies at a concentration of 0.1 brain equivalent. Allatostatins and crustacean cardioactive peptide, which are both present in cricket brains, are not responsible for this inhibiting effect. Octopamine causes a dose‐dependent inhibition of acetate incorporation whereas synephrine had no such effect. The inhibiting effect of Grb‐AKH on the formation of lipid stores in the fat body and its consequences for reproductive processes are discussed. Arch. Insect Biochem. Physiol. 47:198–214, 2001. © 2001 Wiley‐Liss, Inc.
Pharmacokinetics of E‐6087, a new anti‐inflammatory agent, in rats and dogs
Authors: Reinoso Raquel F. , Farrán Ramón , Moragón Trinidad , García‐Soret Antonio , Martínez Lluis
Published: September 2002

The pharmacokinetics of E‐6087, a newly developed cyclooxygenase‐2 inhibitor, was studied in rats and dogs after single oral and intravenous doses. In both animal species, E‐6087 was characterized by a long elimination half‐life (20–35 h), a low plasma clearance (0.10–0.22 l h−1 kg−1) and a relatively large volume of distribution (2–6 l kg−1). Oral bioavailability was lower in dogs than in rats whereas a faster elimination was found in rats. Multiple peaks were present regardless of administration route and animal species, suggesting the existence of enterohepatic circulation. Gender effect on the pharmacokinetics of E‐6087 was only found in rats, with greater exposure and longer elimination in females than in males. Food intake reduced the bioavailability (∼22%) with no apparent changes in the absorption rate. After oral dosing of 1, 5 and 25 mg kg−1 to rats, linearity was lost at the highest dose due to the low aqueous solubility of E‐6087. Drug absorption was improved by micronization. E‐6087 and E‐6132, (a pharmacologically active metabolite), showed different pharmacokinetics. The higher percentage of E‐6087 at early times suggests that E‐6087 is the main compound responsible for in vivo activity, although E‐6132 would contribute to the activity at later times. Copyright © 2001 John Wiley & Sons, Ltd.
Does neuronal loss in Parkinson's disease involve programmed cell death?
Authors: Andersen Julie K.
Published: September 2002

Recently it has been hypothesized that apoptotic cell death is involved in several neuropathological conditions including Parkinson's disease (PD). Initial morphological studies assessing the presence of apoptosis in Parkinsonian brain tissues yielded mixed results. Based on more recent studies in human PD brains as well in animal and cell culture models of the disease, a picture is emerging, however, that strongly suggests that many of the molecular players thought to participate in this type of neuronal cell death are active in the disease. The task of researchers in the field is now to deduce how these players may be interacting with one another to bring about cell death in PD and to design effective therapies to interfere with these processes. BioEssays 23:640–646, 2001. © 2001 John Wiley & Sons, Inc.
Longterm stability of phase I and phase II enzymes of porcine liver cells in flat membrane bioreactors
Authors: Langsch Angelika , Bader Augustinus
Published: September 2002

Recently, researchers have focused on the use of bioartificial liver devices to support patients with fulminant hepatic failure. Our team developed a cell‐based flat membrane bioreactor (FMB). In this, porcine liver cells were maintained in 3D‐coculture between two gel layers in a sandwich configuration for 3 weeks to study the influence of this bioreactor technique on the preservation of basic, not induced activities of phase I and phase II enzymes. First, the time and substrate dependencies of the following enzymes were measured: ethoxyresorufin‐O‐deethylase (EROD, CYP 1A1/1A2) and ethoxycoumarin‐O‐deethylase (ECOD, CYP 2B6) as phase I enzymes, and glutathione‐S‐transferase (GST), UDP‐glucuronosyltransferase (UGT) and sulfotransferase (ST) as phase II enzymes. To find optimal test conditions Michaelis‐Menten kinetics were calculated. Next, different potential inducers were tested to find out the most effective compounds. Based on these results, the basic, not induced levels of the different enzymes were determined in the flat membrane bioreactor. Furthermore, the response of these enzyme activities to the chosen inducers was investigated to examine whether the cells keep their ability for drug–drug interactions. Basic, not induced activities of both phase I enzymes and the phase II enzymes GST and UGT were maintained at nearly the initial levels during the complete period of study. In addition, it was possible to induce these enzymes twice or three times in a weekly interval. In contrast, the basic, not induced activity of ST increased during the first 10 days of culture. It stabilized then and was maintained steady. As in short‐term investigations, no reaction of the ST‐activity towards any inducer could be obtained. These results prove that porcine liver cells preserve their phase I and phase II activities and respond to inducing drugs over 3 weeks in culture. Therefore, the flat membrane bioreactor is not only suitable for investigating drug metabolism, drug–drug interactions, and enzyme induction but also for supporting liver functions. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 76: 115–125, 2001.
Coronary angioplasty and Rotablator atherectomy trial (CARAT): Immediate and late results of a prospective multicenter randomized trial
Authors: Safian Robert D. , Feldman Ted , Muller David W.M. , Mason Denise , Schreiber Theodore , Haik Bruce , Mooney Michael , O'Neill William W.
Published: September 2002

Mechanical rotational atherectomy with the Rotablator is widely used for percutaneous coronary revascularization, but the ideal debulking strategy remains unknown. The purpose of this study was to compare the immediate and late results after Rotablator using two treatment strategies: Large burrs (burr/artery ratio of >0.7) to achieve maximal debulking (lesion debulking strategy) or small burrs (burr/artery ratio ≤ 0.7) to modify lesion compliance (lesion modification strategy). Two hundred twenty‐two patients at six centers were prospectively enrolled in this study and randomly assigned to large (n = 104 patients with 118 lesions) or small (n = 118 patients with 136 lesions) burrs. The primary endpoint was final diameter stenosis at the end of the procedure, and secondary endpoints included inhospital angiographic and clinical complications, and target lesion revascularization at 6 months. Baseline demographic and angiographic characteristics were similar. There were no differences in procedural success, the extent of immediate lumen enlargement, inhospital ischemic complications, or late target vessel revascularization. However, compared with small burrs, patients randomized to large burrs were more likely to experience serious angiographic complications (5.1% vs. 12.7%, P < 0.05) immediately after atherectomy. This study suggests that a routine lesion modification strategy employing small burrs (burr/artery ratio ≤ 0.7) achieves similar immediate lumen enlargement and late target vessel revascularization compared with a more aggressive debulking strategy (burr/artery ratio >0.7), but with fewer angiographic complications. Cathet Cardiovasc Intervent 2001;53:213–220. © 2001 Wiley‐Liss, Inc.
Evaluation of the percutaneous intramyocardial injection for local myocardial treatment
Authors: Rezaee Mehrdad , Yeung Alan C. , Altman Peter , Lubbe Dieter , Takeshi Suzuki , Schwartz Robert S. , Stertzer Simon , Altman John D.
Published: September 2002

Therapeutic angiogenesis requires the induction of new blood vessel formation for the treatment of peripheral vascular and coronary artery disease. Efficacious application of this new therapy requires optimizing multiple factors, including the therapeutic agent, dosing, frequency of administration, and delivery modality. In this study, a helical needle drug infusion catheter was applied for optimal application of percutaneous intramyocardial delivery (PIMD). 125Iodine‐labeled albumin was injected by PIMD into the left ventricle myocardium in eight swine. After 1 hr, PIMD resulted in a high concentration of radiolabel at the treatment site; 16.4% ± 2.1% of delivered and 81.4% ± 2.6% of the total cardiac activity was concentrated at the site of delivery. The depth of needle penetration correlated with the myocardial retention of delivered protein. The myocardial retention of radiolabel in animals with shallow injections was 10.1% ± 0.8%, compared to 18.9% ± 3.3% retention after deep injections. The specific activity at the treatment site (radioactive counts per gram of tissue) was 115 ± 36, 226 ± 55, and 47 ± 10 times higher compared to liver, lung, and kidney, respectively. Continuous coronary sinus and aortic blood sampling indicates that within 15 min following intramyocardial injection, a significant amount of nonretained protein is found within the coronary sinus. This study defines some of the parameters that can affect optimal application of PIMD and demonstrates that PIMD is a safe and efficient method for local drug delivery. Cathet Cardiovasc Intervent 2001;53:271–276. © 2001 Wiley‐Liss, Inc.
Pathways to participation: openings, opportunities and obligations
Authors: Shier Harry
Published: September 2002

The United Nations Convention on the Rights of the Child has raised the profile of children's participation in the United Kingdom. Hart's ‘ladder of participation’ has been the most influential model in this field. This paper offers an alternative model, based on five levels of participation: 1. Children are listened to. 2. Children are supported in expressing their views. 3. Children's views are taken into account. 4. Children are involved in decision‐making processes. 5. Children share power and responsibility for decision‐making. In addition, three stages of commitment are identified at each level: ‘openings’, ‘opportunities’ and ‘obligations’. The model thus provides a logical sequence of 15 questions as a tool for planning for participation. Copyright © 2001 John Wiley & Sons, Ltd.
Shape diversity among chick retina Müller cells and their postnatal differentiation
Authors: Anezary Lyazed , Medina Juan I. , Sánchez‐Nogueiro Jesüs , López‐Gallardo Meritxell , Prada Carmen
Published: September 2002

It is currently believed that in each vertebrate species Müller cells in the central retina constitutes a fairly homogeneous population from the morphologic point of view and that particularly the chick Müller cell attains full shape differentiation at prenatal stages. However, in this study of the chick retina, from day 1 to day 55 of life, we show that there is a large variety of Müller cell shapes and that many of them complete shape differentiation postnatally. We used a cell dissociation method that preserves the whole shape of the Müller cells. Unstained living and unstained fixed cells were studied by phase‐contrast microscopy, and fixed cells immunostained for intermediate filaments of the cytoskeleton were studied by fluorescence microscopy. Our results show that (1) Müller cell shapes vary in the origination of the hair of vitread processes, in the shape of the ventricular (outer or apical) process, in the presence or absence of an accessory process, as well as in the number and shape of processes leaving from the ventricular process at the level of the outer nuclear and outer plexiform layers (ONL/OPL); (2) during the first month of life, many Müller cells differentiate the portion of the ventricular process that traverses the ONL, most Müller cells differentiate the ONL/OPL processes, and all Müller cells differentiate the thin short lateral processes leaving from the vitread hair processes at the level of the inner plexiform layer (IPL). The number of cells differing in the shape of the ventricular process and that of cells with and without accessory process were estimated. The spatial relationship between the outer portion of the ventricular process of the Müller cell and the photoreceptor cells was also studied. Our results show that the branching of the ventricular process and the refinement of Müller cell shape is achieved without apparent participation of growth cones. We give a schematic view of how the branching of the ventricular process might take place and propose the size increase of photoreceptor soma as a factor responsible for this branching. J. Comp. Neurol. 438:32–49, 2001 © 2001 Wiley‐Liss, Inc.
Simulation study on ATM multiplexing of MPEG video sources
Authors: Feng J. , Lo K.‐T.
Published: September 2002

In this paper we study the performance of ATM multiplexing of homogeneous MPEG video sources. A source scheduling method is developed to improve the performance of ATM multiplexer for MPEG video sources. Simulation results show that the level of burstiness for the aggregated MPEG traffic is reduced and the network performance is enhanced. Based on the rationale of the source scheduling method, a simple but efficient bandwidth allocation algorithm is also derived for connection admission of MPEG video in an ATM multiplexer. Copyright © 2001 John Wiley & Sons, Ltd.
Ectonucleotidases: Some recent developments and a note on nomenclature
Authors: Zimmermann Herbert
Published: September 2002

Extracellular nucleotides such as ATP, ADP, UTP, UDP, and also diadenosine polyphosphates act as signaling molecules and can be inactivated by hydrolysis via ectonucleotidases. A considerable number of surface‐located enzymes can potentially be involved in the extracellular hydrolysis pathway. These include the E‐NTPDase family (ectonucleoside triphosphate diphosphohydrolase family), the E‐NPP family (ectonucleotide pyrophosphatase/phosphodiesterase family), ecto‐5′‐nucleotidase, and alkaline phosphatases. In addition, activity of ectonucleoside diphosphokinase can interconvert extracellular nucleotides, and ATP can be used as a cosubstrate of ectoprotein kinase in the phosphorylation of surface‐located proteins. Members of the various ectonucleotidase families reveal overlapping substrate specificity and tissue distribution whose functional significance needs to be further elucidated. Considerable progress has been made in the past several years in characterizing novel enzyme species and their molecular and functional properties. First knock‐out mice reveal insight into physiological processes governed by the activity of specific ectonucleotidases. Together this work has led to a deeper understanding of the pathways of extracellular nucleotide metabolism, including their interplay with P2 and P1 receptors or also other physiological mechanisms. Drug Dev. Res. 52:44–56, 2001. © 2001 Wiley‐Liss, Inc.
Multiple growth factors regulate coronary embryonic vasculogenesis
Authors: Tomanek Robert J. , Zheng Wei , Peters Kevin G. , Lin Pengnian , Holifield Jennifer S. , Suvarna Padma R.
Published: September 2002

Mechanisms regulating coronary vascularization are not well understood. To test hypotheses regarding the influence of key growth factors and their interactions, we studied vascular tube formation (vasculogenesis) in collagen gels onto which quail embryonic ventricles were placed and incubated in the presence of growth factors or inhibitors. Vasculogenesis in this model is dependent on tyrosine kinase receptors, since tube formation was totally blocked by genestein. Tube formation was attenuated when anti‐bFGF or anti‐VEGF neutralizing antibodies were added to the medium and nearly completely inhibited when the both were added. The attenuation associated with anti‐VEGF was due primarily to a decrease in assembly of endothelial cells, while that associated with bFGF was primarily due to a reduction in endothelial cells. Soluble tie‐2, the receptor for angiopoietins, also had an inhibitory effect and, when added with either anti‐bFGF or anti‐VEGF, markedly attenuated tube formation. At optimal doses, tube formation was enhanced 6.5‐fold by bFGF and 2.5‐fold by VEGF over the controls. Each of these growth factors was dependent upon the other for optimal induction of tube formation, since neutralizing antibodies to one markedly reduced the potency of the other. VEGF potency was also markedly reduced when soluble tie‐2 was added to the medium. Tube formation was virtually totally blocked by exogenous TGF‐β at doses > 1 ng/ml, while neutralizing TGF‐β antibodies enhanced tube formation 2‐fold in the 30 ng–30 μg range. These data provide the first documentation of multiple growth factor regulation of coronary tube formation. © 2001 Wiley‐Liss, Inc.
The perichondrium plays an important role in mediating the effects of TGF‐β1 on endochondral bone formation
Authors: Alvarez Jesus , Horton Jennifer , Sohn Philip , Serra Rosa
Published: September 2002

Endochondral bone formation is complex and requires the coordination of signals from several factors and multiple cell types. Thus, chondrocyte differentiation is regulated by factors synthesized by both chondrocytes and cells in the perichondrium. Previously, we showed that expression of a dominant‐negative form of the transforming growth factor β (TGF‐β) type II receptor in perichondrium/periosteum resulted in increased hypertrophic differentiation in growth plate chondrocytes, suggesting a role for TGF‐β signaling to the perichondrium in limiting terminal differentiation in vivo. Using an organ culture model, we later demonstrated that TGF‐β1 inhibits chondrocyte proliferation and hypertrophic differentiation by two separate mechanisms. Inhibition of hypertrophic differentiation was shown to be dependent on Parathyroid hormone‐related peptide (PTHrP) and expression of PTHrP mRNA was stimulated in the perichondrium after treatment with TGF‐β1. In this report, the hypothesis that the perichondrium is required for the effects of TGF‐β1 on growth and/or hypertrophic differentiation in mouse metatarsal organ cultures is tested. Treatment with TGF‐β1 inhibited expression of type X collagen mRNA in metatarsal cultures with the perichondrium intact. In contrast, hypertrophic differentiation as measured by expression of Type X collagen was not inhibited by TGF‐β1 in perichondrium‐free cultures. TGF‐β1 added to intact cultures inhibited BrdU incorporation in chondrocytes and increased incorporation in the perichondrium; however, TGF‐β1 treatment stimulated chondrocyte proliferation in metatarsals from which the perichondrium had been enzymatically removed. These results suggest that the TGF‐β1‐mediated regulation of both chondrocyte proliferation and hypertrophic differentiation is dependent upon the perichondrium. Thus, one or several factors from the perichondrium might mediate the way chondrocytes respond to TGF‐β1. © 2001 Wiley‐Liss, Inc.
Sensorless control of SRM based on a simple expression of magnetization characteristics
Authors: Kosaka Takashi , Matsui Nobuyuki , Saha Subrata , Takeda Yoji
Published: September 2002

Switched reluctance motors (SRM) have a simpler and more rugged construction than conventional ac motors, and hence are suitable for low‐cost variable‐speed drives in many industrial applications. However, the need to use a traditional position sensor for their control is one of the disadvantages of SRM from the standpoints of cost, size, and reliability. For practical use, there is a need for sensorless drive of SRM. This paper describes position‐sensorless control of SRM based on a simple expression of their nonlinear magnetization characteristics. Successful experiments using a 1.5‐kW, 5400‐rpm SRM with a 6/4 pole configuration have verified the practicability of the proposed sensorless control scheme. © 2001 Scripta Technica, Electr Eng Jpn, 137(2): 52–60, 2001
The importance of self‐diagnosis and self‐evaluation for an EMS set‐up
Authors: Orecchini Fabio , Sabatini Debora , Cedola Luca
Published: September 2002

Environmental management systems (EMSs) have been developed to improve environmental performance of organizations towards the diffusion of sustainability in industrial production. The ISO 14000 series of International Standards is the most important reference for eco‐management of any type of organization. The EMS implementation can be developed more fluently and with less effort (in terms of human resources and costs) and time by applying, before the Environmental Review, a ‘self‐diagnosis and self‐evaluation (SD&E)’. The ISO 14000 series, in fact, guides the organizations to start the system elaborating their Environmental Policy and Environmental Review.

The case study described is the environmental SD&E carried out on a Valli Zabban S.p.A. industrial site. The chemical industry in question is the leader in Italy in the production of bitumen and bituminous membranes; it has already developed an advanced quality system (certified ISO 9001/94) and is now working with our environmental research group to reach the ISO 14000 certification.

The most relevant convenience of introducing that step is that the company is ready, once it has completed the self‐evaluation, to start the implementation of its EMS with more awareness of the environmental situation in its various activities and to prepare a favourable ‘atmosphere’ and expectations company wide. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
Does momentary assessment detect binge eating in overweight women that is denied at interview?
Authors: Grange Daniel le , Gorin Amy , Catley Delwyn , Stone Arthur A.
Published: September 2002

Binge eating is a common problem among overweight people and may complicate weight loss treatment. Addressing binge eating in treatment requires an understanding of the factors that trigger these episodes. Forty‐two women were selected from a community sample that expressed interest in the study. An Ecological Momentary Assessment (EMA) method was used that enabled participants to monitor their eating, feelings and behaviours for 14 days, using programmable wristwatches, at random times, before all eating episodes and just after binge eating episodes. Of these, 18 BED women and 17 women with no BED (NBED) were retained for the statistical analyses. The most important finding was that BED and NBED subjects reported similar levels of binge eating when studied in this way. Negative affect, restraint and lower levels of positive affect were noted as antecedents for binge eating in both BED and NBED participants. Stress and desire to binge, however, were higher for BED participants, compared to NBED participants, prior to normal eating and binge eating episodes. EMA was a valuable method to make assessments of binge eating behaviours in participants' natural environment. BED and NBED participants showed more similarities than differences in terms of the frequency of binge eating as well as binge antecedents. Both EMA as well as the similarities between BED and NBED participants may have implications for the diagnosis of BED. Copyright © 2001 John Wiley & Sons, Ltd and Eating Disorders Association.
A fractionally integrated exponential model for UK unemployment
Authors: Gil‐Alana L.A.
Published: September 2002

Fractionally integrated models with the disturbances following a Bloomfield (1973) exponential spectral model are proposed in this article for modelling UK unemployment. This gives us a better understanding of the low‐frequency dynamics affecting the series without relying on any particular ARMA specification for its short‐run components which, in general, require many more parameters to estimate. The results indicate that this exponential model, confounded with fractional integration, may be a feasible way of modelling unemployment. It also shows that its order of integration is much higher than one and thus leads to the conclusion that the standard practice of taking first differences may lead to erroneous results. Copyright © 2001 John Wiley & Sons, Ltd.
Intraday Volatility in Interest‐Rate and Foreign‐Exchange Markets: ARCH, Announcement, and Seasonality Effects
Authors: Ederington Louis , Lee Jae Ha
Published: September 2002

We explore the determinants of intraday volatility in interest‐rate and foreign‐exchange markets, focusing on the importance and interaction of three types of information in predicting intraday volatility: (a) knowledge of recent past volatilities (i.e., ARCH or Autoregressive Conditional Heteroskedasticity effects); (b) prior knowledge of when major scheduled macroeconomic announcements, such as the employment report or Producer Price Index, will be released; and (c) knowledge of seasonality patterns. We find that all three information sets have significant incremental predictive power, but macroeconomic announcements are the most important determinants of periods of very high intraday volatility (particularly in the interest‐rate markets). We show that because the three information sets are not independent, it is necessary to simultaneously consider all three to accurately measure intraday volatility patterns. For instance, we find that most of the previously documented time‐of‐day and day‐of‐the‐week volatility patterns in these markets are due to the tendency for macroeconomic announcements to occur on particular days and at particular times. Indeed, the familiar U‐shape completely disappears in the foreign‐exchange market. We also find that estimates of ARCH effects are considerably altered when we account for announcement effects and return periodicity; specifically, estimates of volatility persistence are sharply reduced. Separately, our results show that high volatility persists longer after shocks due to unscheduled announcements than after equivalent shocks due to scheduled announcements, indicating that market participants digest information much more quickly if they are prepared to receive it. However, contrary to results from equity markets, we find no evidence of a meaningful difference in volatility persistence after positive or negative price shocks. © 2001 John Wiley & Sons, Inc. Jrl Fut Mark 21: 517–552, 2001
Localization of taurine transporters, taurine, and 3H taurine accumulation in the rat retina, pituitary, and brain
Authors: Pow David V. , Sullivan Robert , Reye Peter , Hermanussen Siobhan
Published: September 2002

The nervous system contains an abundance of taurine, a neuroactive sulfonic acid. Antibodies were generated against two cloned high‐affinity taurine transporters, referred to in this study as TAUT‐1 and TAUT‐2. The distribution of such was compared with the distribution of taurine in the rat brain, pituitary, and retina. The cellular pattern of [3H] taurine uptake in brain slices, pituitary slices, and retinas was examined by autoradiography. TAUT‐2 was predominantly associated with glial cells, including the Bergmann glial cells of the cerebellum and astrocytes in brain areas such as hippocampus. Low‐level labeling for TAUT‐2 was also observed in some neurones such as CA1 pyramidal cells. TAUT‐1 distribution was more limited; in the posterior pituitary TAUT‐1 was associated with the pituicytes but was absent from glial cells in the intermediate and anterior lobes. Conversely, in the brain TAUT‐1 was associated with cerebellar Purkinje cells and, in the retina, with photoreceptors and bipolar cells. Our data suggest that intracellular taurine levels in glial cells and neurons may be regulated in part by specific high‐affinity taurine transporters. The heterogeneous distribution of taurine and its transporters in the brain does not reconcile well with the possibility that taurine acts solely as a ubiquitous osmolyte in nervous tissues. GLIA 37:153–168, 2002. © 2002 Wiley‐Liss, Inc.
Neurons modulate oxytocin receptor expression in rat cultured astrocytes: Involvement of TGF‐β and membrane components
Authors: Mittaud Peggy , Labourdette Gérard , Zingg Hans , Guenot‐Di Scala Dominique
Published: September 2002

We examined the effect of neurons on oxytocin (OT) receptors (OTR) and OTR gene expression in cultured astrocytes. The addition of neuron‐conditioned medium induced an increase of both OTR binding and OTR mRNA level. This effect was enhanced after the medium was boiled or acidified. As it is known that transforming growth factor‐β (TGF‐β) can be released from carrier proteins by acid or heat, TGF‐β1 and 2 were tested and found to induce an increase of OTR binding. Furthermore, TGF‐β antibody abolished the stimulatory effect of normal or acidified neuron‐conditioned medium. Neurons added to cultured astrocytes without contact mimicked the stimulatory effect of the conditioned medium. In contrast, neurons added with contact, induced a decrease in OTR binding and an increase of mRNA level, whereas neuronal membranes induced a decrease of both OTR binding and mRNA levels. In conclusion, the present data demonstrate that in vitro, neurons are able to modulate astrocytic OTR expression at the level of both protein and mRNA. They stimulate this expression through their release of TGF‐β and inhibit it by the action of unknown membrane components. GLIA 37:169–177, 2002. © 2002 Wiley‐Liss, Inc.
Clinically significant depressive symptoms and very mild to mild dementia of the Alzheimer type
Authors: Rubin Eugene H. , Veiel Lori L. , Kinscherf Dorothy A. , Morris John C. , Storandt Martha
Published: September 2002

Objective

To compare depressive symptoms reported by persons with very mild or mild dementia of the Alzheimer type (DAT) with those reported for the person by a collateral source.

Design

Cross‐sectional evaluation.

Setting

Washington University Alzheimer's Disease Research Center.

Participants

Consecutive series of elderly volunteers (n = 156) enrolled in longitudinal studies with a Clinical Dementia Rating (CDR) of 0.5 (very mild) or 1 (mild). Twenty‐one per cent (n = 33) exhibited clinically significant depressive symptoms for which treatment was recommended.

Main outcome measures

Presence and frequency of DSM‐IV depressive symptoms within the last year and last month reported by the participant or collateral source as ascertained by clinical examination and structured interviews.

Results

Collateral source information is essential in diagnosing clinically significant depressive symptoms. The Geriatric Depression Scale scores correlate with participant information only and therefore may substantially underestimate depression. Depressive symptoms fluctuate in individuals with DAT. The most consistent depressive symptoms are depressed mood, fatigue and indecision.

Conclusions

Clinically significant depressive symptoms may be common in individuals with very mild or mild DAT, although they may fluctuate. Information from both a knowledgeable collateral source and the participant is important for detection of depressive symptoms. Copyright © 2001 John Wiley & Sons, Ltd.
Longitudinal follow‐up of depressive symptoms among normal versus cognitively impaired elderly
Authors: Li Yan‐Sheng , Meyer John S. , Thornby John
Published: September 2002

Objectives

This prospectively designed longitudinal study assesses prevalence, incidence and prognosis of depressive symptoms among cognitively normal elderly volunteers compared with patients with mild cognitive impairment (MCI), dementia of Alzheimer type (DAT), and vascular dementia (VAD). Possible relationships between depressive symptoms, cognitive performance, disease types, and effects of antidepressant treatment were analyzed.

Methods

Two hundred and ninety four subjects exhibiting different levels of cognitive performance were admitted to this study. Demographics, cardiovascular and neurodegenerative risk factors, together with measures of neuropsychological test performance, were obtained at sequential visits. Depressive symptoms were selectively treated with antidepressant medications.

Results

One hundred and forty six subjects with normal cognition, 19 subjects with MCI, 42 patients with DAT, and 32 patients with VAD were followed for a mean of 3.5 years. With the passage of time, there were trends showing prevalence of depressive symptoms to decrease among DAT and to increase among VAD patients. VAD patients exhibited the highest incidences of new‐onset depressive symptoms, followed in incidence by DAT and MCI groups. Depressive symptoms among VAD and MCI patients were more persistent and refractory to antidepressant medications than for DAT patients. Trends suggested that antidepressant treatment might benefit MCI and VAD subjects more than DAT patients. Motivationally related depressive symptoms accounted for major components of elevated Hamilton depression rating scale scores.

Conclusions

Depressive symptoms among DAT patients have higher rates of spontaneous resolution, without requiring intensive drug treatment, than among VAD patients in whom depressive symptoms are more persistent and refractory to drug treatment. Early depressive symptoms among subjects with MCI may represent a preclinical sign and should be considered as a risk factor for impending DAT or VAD among the elderly. Copyright © 2001 John Wiley & Sons, Ltd.
Serial positron emission tomography scans following radiation therapy of patients with head and neck cancer
Authors: Greven Kathryn M. , Williams Daniel W. , McGuirt W. Frederick , Harkness Beth A. , D'Agostino Ralph B. , Keyes John W. , Watson Nat E.
Published: September 2002

Background

A single institution study was undertaken to evaluate the role of positron emission tomography (PET) scans with fluorodeoxyglucose (FDG) prior to radiation and following radiation.

Methods

Forty‐five patients with head and neck cancers were evaluated with FDG‐PET scans as well as either CT or MRI prior to treatment with definitive radiation (RT). These same scans were obtained following completion of RT at 1 month (36 patients), 4 months (28 patients), 12 months (19 patients), and 24 months (15 patients). Standard uptake values (SUV) normalized for blood glucose and lean body mass were calculated on the initial and 1‐month post‐treatment PET scans.

Results

Fifteen patients are alive without evidence of disease at 24 to 52 months following RT. Initial SUVs were calculated on the primary tumor site and ranged from 2.5 to 28.5. These values did not have any correlation with local control when examined for the entire group, primary site, or T stage. One‐month post‐RT SUV ranged from 1.8 to 6.24. Of the 36 1‐month post‐RT PET scans, six were interpreted as positive for residual disease and were confirmed by biopsy. Four of the five scans, which were interpreted as equivocal, were positive on biopsy. Seven of the 25 scans, which were interpreted as negative for tumor, were positive on biopsy. Four‐month scans were more accurate for disease with disease noted in 0 of 18 negative scans, 6 of 7 positive scans, and 2 of 3 equivocal scans.

Conclusions

PET is useful for initial imaging of head and neck cancers. SUV does not appear to be useful for predicting outcome following treatment with RT. One‐month post‐RT scans were inaccurate for predicting the presence of cancer. Four‐month post‐RT scans were a better predictor for the presence of cancer. © 2001 John Wiley & Sons, Inc. Head Neck 23: 942–946, 2001.
Cervical nodal metastases in squamous cell carcinoma of the head and neck: What to expect
Authors: Mukherji Suresh K. , Armao Diane , Joshi Varsha M.
Published: September 2002

The treatment and management of malignancies of the head and neck is directly altered by the presence of metastatic cervical adenopathy. The treatment of nodal metastases in squamous cell carcinoma of the head and neck (HNSCCA) is determined by the lymphatic drainage of the upper aerodigestive tract. The lymphatic drainage is site‐specific and occurs in a predictable manner. The purpose of this text is to provide an overview of the normal routes of lymphatic drainage in the head and neck and correlate this with the current nodal classification system. The specific aims of this manuscript are to 1) illustrate the expected lymphatic drainage patterns of HNSCCA arising in the different subsites (nasopharynx, oropharynx, oral cavity, larynx, and hypopharynx) and 2) review the expected frequency of metastases within nodal groups for HNSCCA that arise in these locations. An understanding of the topographical distribution and incidence of cervical lymph node metastases plays an integral role in the physical examination and radiological evaluation of patients with HNSCCA. For the neuroradiologist, this information may increases the ability to identify those nodal groups at risk for metastatic involvement. © 2001 John Wiley & Sons, Inc. Head Neck 23: 995–1005, 2001.
Ventral tegmental nucleus of Gudden: A pontine hippocampal theta generator?
Authors: Bassant Marie‐Hélène , Poindessous‐Jazat Frédérique
Published: September 2002

It is well‐established that rhythmically bursting (RB) activity in the medial septum is crucial for the generation of the hippocampal theta rhythm, but the contribution of other diencephalic‐pontine structures is less documented. The ventral tegmental nucleus (VTn) of Gudden is related to the Papez's circuit via its interconnections with the medial mammillary nucleus, and therefore it may play a role in the generation of hippocampal theta. In the present study, extracellular activity from VTn neurons were recorded in unanesthetized restrained rats (n = 9). Hippocampal activity (EEG) and electromyograms were recorded simultaneously to identify sleep‐waking states. RB activity was observed in VTn during wakefulness, with periods of hippocampal theta and during rapid eye movement (REM) sleep. Rhythmicity in VTn preceded theta activity in hippocampus. The frequency of RB neurons in VTn was 5.6 Hz during wakefulness and 6.8 Hz during REM sleep. It was similar to that of hippocampal theta. The rhythmicity was particularly stable and the firing rates were strikingly high during REM sleep. RB activity in VTn was also recorded from urethane‐anesthetized rates (n = 3). Rhythmic firing (4.0 Hz) was slower than in unanesthetized rats and matched the urethane‐related theta frequency. Our results show that neurons in VTn exhibit a marked RB activity during states of vigilance accompanied by hippocampal theta rhythm. They suggest that VTn may be a pontine hippocampal theta generator. Hippocampus 2001;11:809–813. © 2001 Wiley‐Liss, Inc.
A pilot, open clinical study of depakote in the treatment of cocaine abuse
Authors: Halikas James A. , Center Bruce A. , Pearson Victoria L. , Carlson Gregory A. , Crea Fredrick
Published: September 2002

The effectiveness of increasing levels of valproic acid on cocaine abstinence was evaluated in an open‐label trial of 55 subjects. Significantly lower percentages of individuals with valproate serum levels above 50 mcg/ml reported cocaine use and had less positive urinalyses as compared to those with serum levels less than 50 mcg/ml. The total number of days of cocaine use decreased significantly (p < 0.001) and improved levels of subject functioning were found with increasing serum levels of valproic acid. This pilot study offers confirmation that the divalproex sodium form of valproic acid, when used in sufficient serum levels, may provide an effective pharmacologic adjunct in the management and treatment of cocaine dependency. Copyright © 2001 John Wiley & Sons, Ltd.