bluuebunny/crossref_metadata_2025 huggingface dataset:
Executive functioning in psychogeriatric patients: scalability and construct validity of the Behavioral Dyscontrol Scale (BDS)
Authors: Diesfeldt Han F. A.
Published: October 2004

Objectives

Item response theory was used to test the scalability of the Behavioral Dyscontrol Scale (BDS). The BDS assesses the control of voluntary movement, working memory and self‐monitoring. Construct validity of the BDS was examined with confirmatory factor analysis.

Methods

The BDS was administered to 693 consecutive, community‐dwelling visitors of a psychogeriatric day unit (424 women and 269 men between the ages of 50 and 94). Unidimensionality of the BDS was determined using Mokken's scalogram analysis. The BDS total score was correlated with other measures of executive function (Expanded Mental Control Test, category fluency, and alternating graphical sequences) and with episodic memory tests of orientation and delayed picture recognition in order to test a model of distinct latent constructs of executive functioning and episodic memory.

Results

Loevinger's scalability coefficient H was 0.58 for the complete item set of the BDS. Subjects can be ordered on the latent dimension of executive ability. The first eight items of the BDS (deleting the insight rating) satisfy the assumption of non‐intersecting item characteristic curves (double monotonicity) which means that they comprise a Guttman‐ordered scale (H = 0.60). The BDS and three independent measures of executive control strongly correlated with a latent construct of executive functioning (convergent validity). However, discriminant relations with a nonexecutive construct (recognition memory and orientation) could not be demonstrated.

Conclusions

The BDS satisfies criteria for scalability according to item response theory. Its construct validity as an executive‐specific measure is as yet unclear. Copyright © 2004 John Wiley & Sons, Ltd.
A systematic review of the utility of self‐report alcohol screening instruments in the elderly
Authors: O'Connell Henry , Chin Ai‐Vyrn , Hamilton Fiona , Cunningham Conal , Walsh J. B. , Coakley Davis , Lawlor Brian A.
Published: October 2004

Background

Effective screening instruments are needed for the detection of alcohol use disorders (AUDs) in the elderly, in view of the significant physical, psychological and social problems associated with this phenomenon.

Methods

This paper provides details on the different self‐report alcohol screening instruments that have been studied in the elderly, describing both the instruments themselves and their effectiveness as screening instruments for AUDs in different elderly populations.

Results

The vast majority of studies reviewed were carried out in the US, and a high proportion of these were carried out in Veterans Administrations institutions, thus limiting the generalizability of results. The CAGE was the most widely studied screening instrument, followed by the MAST or variations of the MAST, the AUDIT and variations of the AUDIT, and other screening instruments. Sensitivity and specificity of these instruments varied widely, depending on the prevalence of AUDs in the population being studied, the clinical characteristics of the population and the type of AUD being detected. The CAGE performed poorly in psychiatric populations but a newer instrument, the AUDIT‐5, has had promising results to date. No studies focussed on elderly people with cognitive impairment, and there is a need for research in this area.

Conclusions

Ease of use, patient acceptability, sensitivity and specificity must all be considered when selecting a self‐report alcohol screening instrument for use in the elderly. Furthermore, the prevalence of AUDs in the population and the clinical characteristics of that population must also be taken into account. Copyright © 2004 John Wiley & Sons, Ltd.
Older women's cognitive and affective response to moderate drinking
Authors: Zimmerman Teena , McDougall Graham J. , Becker Heather
Published: October 2004

Objective

In this paper we investigated the question, how do older women who drink moderate amounts of alcohol differ from those who do not drink on measurements of cognitive function, memory, affect and health?

Methods

The nonprobability sample of female participants (n = 182) averaged 75 years of age and had a Mini Mental State Examination scores of 28. The participants were asked to indicate whether they drank alcohol or abstained (yes/no) and if they indicated that they did drink, to describe how many drinks they consumed in a given period of time (day/week/month).

Results

None of the participants acknowledged drinking more than 2 drinks a day. Caucasian women had the largest number of moderate drinkers (53% vs 47%), while the majority of African–American and Hispanic women reported not drinking. The moderate drinkers reported less depression, had higher self‐reported health, performed better on instrumental everyday tasks, had stronger memory self‐efficacy, and used more strategies to improve memory performance. In addition, these women had higher performance on tests of executive function: attention, concentration, psychomotor skills, verbal‐associative capacities, and oral fluency.

Conclusions

The circumstances under which people drink are complex and were not evaluated in this study. Therefore, rather than endorsing drinking behavior, these findings suggest that future research might examine why elders make the decision to drink, the circumstances that predispose women to drink (alone/with others), and other qualities that characterize female drinkers over the age of 65. Copyright © 2004 John Wiley & Sons, Ltd.
Cellular alignment by grafted adhesion peptide surface density gradients
Authors: Kang Catherine E. , Gemeinhart Ernest J. , Gemeinhart Richard A.
Published: October 2004

The extracellular matrix and extracellular matrix‐associated proteins play a major role in growth and differentiation of tissues and organs. To date, few methods have been developed that allow researchers to examine the affect of surface density gradients of adhesion molecules in a controlled manner. Fibroblasts cultured on surfaces with a surface density gradient of RGD peptide aligned parallel to the gradient while fibroblasts on constant density RGD surfaces spread but did not align as has been shown in numerous earlier studies. Not only did fibroblasts align on the gradient surfaces, but they also showed significantly greater elongation than on constant density peptide surfaces or on control surfaces. This type of method is easy to replicate and can be used by laboratories interested in investigating alignment of various cell types without mechanical force or other stimulation, and without cell–cell interaction or for investigation of affects of surface density gradients of molecules on cellular biochemistry and biophysics. This method also has potential applications for developing scaffolds for tissue engineering applications where cellular alignment is necessary. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 403–411, 2004
Fibronectin adsorption on surface‐activated poly(dimethylsiloxane) and its effect on cellular function
Authors: Toworfe George K. , Composto Russell J. , Adams Christopher S. , Shapiro Irving M. , Ducheyne Paul
Published: October 2004

This article reports that surface modification of poly(dimethylsiloxane) (PDMS) influences fibronectin (Fn) adsorption and enhances cell attachment. Controlled adsorption of Fn on chemically activated polymer substrates is known to influence cellular function. Thin films of PDMS were spun cast on silicon wafers to obtain homogeneous and molecularly smooth surfaces. The films were made hydrophilic by exposure to ultraviolet ozone activation (PDMS*). The films then were characterized by contact angle goniometry, ellipsometry, atomic force microscopy (AFM), Rutherford backscattering spectrometry and X‐ray photoelectron spectroscopy. Contact angle measurements indicated higher hydrophobicity of the nonactivated PDMS substrates than PDMS*. AFM scans of the substrates indicated higher surface roughness of PDMS* (Ra = 0.55 nm) than PDMS (Ra = 0.25 nm). Although Fn surface density (Γ) was slightly higher on PDMS than on PDMS*, due to hydrophobic interactions between substrate and Fn, cell function was greatly enhanced on the Fn‐coated PDMS* (PDMS*‐Fn) than on PDMS (PDMS‐Fn). Higher attachment of MC3T3‐E1 osteoblast‐like cells was observed on PDMS*‐Fn than on PDMS‐Fn. Moreover, cell spreading and cytoskeleton organization after 72 h was clearly favored on the Fn‐coated PDMS* surfaces. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 449–461, 2004
Effect of the hydrophilic nanofiller loading on the mechanical properties and the microtensile bond strength of an ethanol‐based one‐bottle dentin adhesive
Authors: Kim Jong‐Soon , Cho Byeong‐Hoon , Lee In‐Bog , Um Chung‐Moon , Lim Bum‐Soon , Oh Myung‐Hwan , Chang Chang‐Gok , Son Ho‐Hyun
Published: October 2004

This study evaluated the hypothesis that if hydrophilic nanofillers were dispersed evenly within the adhesive layer under moist conditions, adding them to a one‐bottle dentin adhesive might improve the mechanical properties of the adhesive layer, and accordingly increase the bond strength. The flexural strength (FS), the degree of conversion (DC), and the microtensile bond strength (MTBS) to the dentin of four experimental ethanol‐based one‐bottle dentin adhesives containing 0, 0.5, 1.0, and 3.0 wt % of 12‐nm hydrophilic fumed silica were evaluated, and the distribution of the nanofillers were compared using transmission electron microscopy (TEM). Although the nanofiller content did not affect the DC, the FS tended to increase with increasing nanofiller content. The MTBS appeared to increase when up to 1.0 wt % of the nanofillers were added, but they were statistically not significant. However, when 3.0 wt % of the nanofillers were added, the MTBS decreased significantly comparing to the adhesive containing 0.5 wt % nanofillers (p < 0.05). The TEM image suggested that if the nanofillers within the adhesive were 3.0 wt % and applied to a wet dentin surface, they aggregated easily into large clusters and would decrease the MTBS. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 72B: 284–291, 2005
Constant pH molecular dynamics in generalized Born implicit solvent
Authors: Mongan John , Case David A. , McCammon J. Andrew
Published: October 2004

A new method is proposed for constant pH molecular dynamics (MD), employing generalized Born (GB) electrostatics. Protonation states are modeled with different charge sets, and titrating residues sample a Boltzmann distribution of protonation states as the simulation progresses, using Monte Carlo sampling based on GB‐derived energies. The method is applied to four different crystal structures of hen egg‐white lysozyme (HEWL). pKa predictions derived from the simulations have root‐mean‐square (RMS) error of 0.82 relative to experimental values. Similarity of results between the four crystal structures shows the method to be independent of starting crystal structure; this is in contrast to most electrostatics‐only models. A strong correlation between conformation and protonation state is noted and quantitatively analyzed, emphasizing the importance of sampling protonation states in conjunction with dynamics. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 2038–2048, 2004
Amniotic membrane graft: Histopathological findings in five cases
Authors: Tosi Gian Marco , Traversi Claudio , Schuerfeld Karin , Mittica Vincenzo , Massaro‐Giordano Mina , Tilanus Maurits A.D. , Caporossi Aldo , Toti Paolo
Published: October 2004

Amniotic membrane transplantation (AMT) is an effective treatment for ocular surface reconstruction; however, the mechanisms through which amniotic membrane (AM) exerts its effects as well as its fate after transplantation have not been entirely elucidated and have been investigated only in part. We evaluate the integration of AM in the host cornea in five patients who underwent AMT as the result of Bowen's disease, band keratopathy, radio‐ or cryotherapy‐induced keratopathy, chemical burn or post‐herpetic deep corneal ulcer with descemetocele. Due to persistent opacification in four cases and a progressing tumor in one case, penetrating keratoplasty (PK) and enucleation were performed as early as 2 months and up to 20 months after AMT. The corneas were analyzed histopathologically. To evaluate AM remnants, corneas were stained with periodic acid Schiff's reaction (PAS), Alcian blue, and Gomory and Masson trichrome; immunostaining including collagens III and IV antibodies was also performed. None of the corneas showed remnants of AM. In all cases, we observed discontinuity of Bowman's membrane. In three cases, the corneal epithelium was completely restored, ranging from three to six cell layers. In the other two cases, we detected an intense inflammatory reaction with rich neovascularization; the epithelial surface of the central cornea was completely restored, while at the periphery of the cornea goblet mucus‐producing cells were present. Although clinically useful in all cases, restoration of a stable corneal epithelium through AMT is limited by the extent and severity of limbal stem cell deficiency (LSCD). The lack of histologically documented AM remnants in our cases seems to explain the efficacy of AMT more through its biological properties than through its mechanical properties. © 2004 Wiley‐Liss, Inc.
Enrichment of Anammox biomass from municipal activated sludge: experimental and modelling results
Authors: Dapena‐Mora Ana , Van Hulle Stijn WH , Luis Campos J , Méndez Ramón , Vanrolleghem Peter A , Jetten Mike
Published: October 2004

Anaerobic Ammonia Oxidising (Anammox) biomass was enriched from sludge collected at a municipal wastewater treatment plant, employing a Sequential Batch Reactor (SBR). After 60 days Anammox activity started to be detected, by consumption of stoichiometric amounts of NO2− and NH4+ in the system. Fluorescence In Situ Hybridisation analysis confirmed the increase of Anammox bacteria concentration with time. A final concentration of enriched biomass of 3–3.5 gVSS dm−3 was obtained, showing a Specific Anammox Activity of 0.18 gNH4+‐N gVSS−1 d−1 The reactor was able to treat nitrogen loading rates of up to 1.4 kgN m−3 d−1, achieving a removal efficiency of 82 %. On the other hand, the start‐up and operation of the Anammox SBR reactor were consequentially modelled with the Activated Sludge Model nr 1, extended for Anammox. The simulations predicted quite well the experimental data in relation to the concentrations of nitrogenous compounds and can be used to estimate the evolution of Anammox and heterotrophic biomass in the reactor. These simulations reveal that heterotrophs still remain in the system after the start‐up of the reactor and can protect the Anammox microorganisms from a negative effect of the oxygen. Copyright © 2004 Society of Chemical Industry
Production of structured triacylglycerols in an immobilised lipase packed‐bed reactor: batch mode operation
Authors: González Moreno PA , Robles Medina A , Camacho Rubio F , Camacho Páez B , Esteban Cerdán L , Molina Grima E
Published: October 2004

Structured triacylglycerols with caprylic acid at the sn‐1 and sn‐3 positions of the glycerol backbone and eicosapentaenoic acid (EPA) at the position sn‐2 were synthesised by acidolysis of a commercially available EPA‐rich oil (EPAX4510, Pronova Biocare) and caprylic acid catalysed by the 1,3‐specific immobilised lipase Lipozyme IM. The reaction was carried out in an immobilised lipase packed‐bed reactor by recirculating the reaction mixture through the bed. The exchange equilibrium constants between caprylic acid and the native fatty acids of EPAX4510 were determined. The n‐3 polyunsaturated fatty acids (PUFAs), EPA and docosohexaenoic acid (DHA), were the most easily displaced by the caprylic acid. The exchange equilibrium constants were 3.68 and 3.06 for EPA and DHA, respectively. The influence of the flow rate of the reaction mixture through the packed‐bed and the substrate concentration in the reaction rate were studied. For flow rates between 74 and 196 cm3 h−1 (bed of 6.6 mm internal diameter and 0.46 porosity) and triacylglycerol concentrations between 0.036 and 0.108 M, the data fitted well to an empirical kinetic model which allowed representative values of the apparent kinetic constant to be obtained. Hence, the average reaction rates and kinetic constants of exchange of caprylic acid and native fatty acids of EPAX4510 could be calculated. In the conditions indicated, the parameter (lipase mass × time/triacylglycerol mass, mLt/V[TG]0) constituted the intensive variable of the process for use in predicting the composition of structured triacylglycerols at different reaction times. At equilibrium, the structured triacylglycerol produced had the following composition: caprylic acid 59.5%, EPA 9.6%, DHA 2.2% and oleic acid 11.8%. Copyright © 2004 Society of Chemical Industry
Analysis of solvation in ionic liquids using a new linear solvation energy relationship
Authors: Lee Sun Bok
Published: October 2004

A new linear solvation energy relationship (LSER) equation, where the solute internal energy term has been incorporated into the traditional LSER equation, is used for the analysis of solvation in ionic liquids. Modeling results obtained using the new LSER equation indicate that all solute parameters (dispersion, polarity, hydrogen bonding, cavity formation, and solute internal energy) have approximately equal importance in the solvation of organic solutes in ionic liquids. The magnitude of dispersion interaction is stronger in ionic liquids than in aqueous solution, whereas hydrogen‐bonding interactions are stronger in water than in ionic liquids. This indicates that the solubility of polar compounds that contain bulky and aromatic groups can be enhanced in ionic liquids due to higher dispersion interactions in ionic liquids than in aqueous solution. On the other hand, the LSER equation without the solute internal energy term does not yield the meaningful solute–solvent interaction terms, indicating that the inclusion of a solute internal energy term is necessary to properly describe the solvation of organic solutes in liquid solvents. Copyright © 2004 Society of Chemical Industry
Limitation phenomena induced by biofilm formation during hydrocarbon biodegradation
Authors: Joannis‐Cassan Claire , Delia Marie‐Line , Riba Jean‐Pierre
Published: October 2004

Limiting factors induced by the formation of a biofilm on the hydrocarbon's surface during in‐situ bioremediation were identified. A liquid–liquid system (hydrocarbon–aqueous solution) and a device made of six fixed‐bed columns packed with sand were successively used on a laboratory‐scale. In the liquid–liquid system, it was shown that biofilm growth was limited by the diffusion of both oxygen and hydrocarbon within the biofilm. At the end of growth, the biofilm thickness reached 80 ± 20µm. In the fixed‐bed columns, additional difficulties were observed. First, distribution of oxygen in the deepest part of the sand was difficult: from 84 to 100% of the biofilm growth occurred in the upper two‐thirds of the sand. Then, the surface of the hydrocarbon available for microorganisms was found to be a limiting factor for the biofilm's development. Copyright © 2004 Society of Chemical Industry
Use of confocal and multiphoton microscopy for the evaluation of micro‐optical components and emitters
Authors: Girkin J.M. , Gu E. , Griffin C. , Choi H.W. , Dawson M.D. , McConnell G.
Published: October 2004

We report on the application of confocal and multiphoton microscopic techniques for the evaluation of the latest generation of micro optical components. The optical emitting characteristics of arrays of matrix addressable GaN micrometer‐sized light emitting diodes (micro‐LEDs) have been measured using a commercial confocal microscope utilising the LEDs' own emission along with reflection confocal microscopy to determine the surface structure. Multiphoton induced luminescence from the 10–20‐micron diameter emitters has also been used to examine the structure of the device and we compare this with electrically induced emission. In related work, the optical properties of micro lens arrays (10–100‐micron diameter) fabricated in SiC, Sapphire, and Diamond have been determined using transmission confocal microscopy. Such optical microscopy techniques offer a simple, non‐destructive method to determine the structure and performance of such novel devices. Microsc. Res. Tech. 64:293–296, 2004. © 2004 Wiley‐Liss, Inc.
Time‐resolved fluorescence microscopy using an improved europium chelate BHHST for the in situ detection of Cryptosporidium and Giardia
Authors: Connally Russell , Veal Duncan , Piper James
Published: October 2004

Fluorescent immunoconjugates prepared with the europium chelate BHHCT (4,4′‐bis(1″,1″,1″,2″,2″,3″,3″‐heptafluoro‐4″,6″‐hexanedion‐6″‐yl)‐chlorosulfo‐o‐terphenyl) have previously been reported as suitable labels for time‐resolved fluorescence applications. BHHCT is limited by a tendency to destabilize immunoglobulins when covalently bound to the protein at moderate to high fluorophore to protein ratios (F/P). We report a new derivative of BHHCT prepared by appending a short hydrophylic tether to the chlorosulfonate activating group on BHHCT. The new derivative, BHHST (4,4′‐bis‐(1″,1″,1″,2″,2″,3″,3″‐heptafluoro‐4″,6″‐hexanedion‐6″‐yl)sulfonylamino‐propyl‐ester‐N‐succinimide‐ester‐o‐terphenyl), was activated to bind at the tether terminus with a succinimide leaving group that displayed less aggressive coupling activity and improved storage stability. BHHST has been used to prepare a stable and useful immunoconjugate with the anti‐Cryptosporidium monoclonal antibody CRY104. The BHHST immunoconjugate provides more than a 10‐fold enhancement in the signal to noise ratio (SNR) of labeled oocyst fluorescence over background when observed using TRFM techniques. An immunoconjugate was also prepared with BHHST and (goat) anti‐mouse that effectively labeled Giardia cysts in situ. Detection of cysts with the TRFM was achieved with an 11‐fold increase in SNR when a gate‐delay of 60 μs was employed. The storage half‐life of both immunoconjugates is extended more than 20‐fold when compared to immunoconjugates prepared with BHHCT. Microsc. Res. Tech. 64:312–322, 2004. © 2004 Wiley‐Liss, Inc.
Histochemical evidence of the initial chondrogenesis and osteogenesis in the periosteum of a rib fractured model: Implications of osteocyte involvement in periosteal chondrogenesis
Authors: Li Minqi , Amizuka Norio , Oda Kimimitsu , Tokunaga Kunihiko , Ito Tomoyuki , Takeuchi Kiichi , Takagi Ritsuo , Maeda Takeyasu
Published: October 2004

We have examined cellular events at the early stages of periosteal chondrogenesis and osteogenesis induced by bone fracture, using a well‐standardized rib fracture model of the mouse. The initial cellular event was recognized as considerable proliferation in the deeper layer referred to as the “cambium layer” of the periosteum, as evidenced by numerous proliferating cell nuclear antigen‐positive cells. The periosteal cartilage and bone were then regenerated directly from the region of the most‐differentiated cell, i.e., mature osteoblasts of the cambium layer both close to and distant from the fracture site. Therefore, periosteal osteoblasts appeared to have the potential to differentiate into chondrogenic and osteoblastic lineages. CD31‐positive blood vessels were uniformly localized along the periosteum that was regenerating cartilage and bone, being therefore indicative of less influence on the initiation of osteochondrogenesis. In contrast, however, the regenerated periosteal cartilage or bone extended from the cortical bones included dead or living osteocytes, respectively. Empty lacunae and lacunae embedded with amorphous materials were found close to the regenerated cartilage, while intact osteocytes persisted adjacent to the regenerated bone. The embedded lacunae with amorphous materials would render the tissue fluid, nutrients, oxygen, and several secretory factors such as dentin matrix protein‐1 impossible to be delivered to the periosteal osteoblasts that interconnect osteocytes via gap junctions. Our study thus provides two major clues on initial cellular events in response to bone fracture: the potentiality of periosteal osteoblastic differentiation into a chondrogenic lineage, and a putative involvement of osteocytes in periosteal cartilage and bone regeneration. Microsc. Res. Tech. 64:330–342, 2004. © 2004 Wiley‐Liss, Inc.
Ion activation methods for tandem mass spectrometry
Authors: Sleno Lekha , Volmer Dietrich A.
Published: October 2004

This tutorial presents the most common ion activation techniques employed in tandem mass spectrometry. In‐source fragmentation and metastable ion decompositions, as well as the general theory of unimolecular dissociations of ions, are initially discussed. This is followed by tandem mass spectrometry, which implies that the activation of ions is distinct from the ionization step, and that the precursor and product ions are both characterized independently by their mass/charge ratios. In collision‐induced dissociation (CID), activation of the selected ions occurs by collision(s) with neutral gas molecules in a collision cell. This experiment can be done at high (keV) collision energies, using tandem sector and time‐of‐flight instruments, or at low (eV range) energies, in tandem quadrupole and ion trapping instruments. It can be performed using either single or multiple collisions with a selected gas and each of these factors influences the distribution of internal energy that the activated ion will possess. While CID remains the most common ion activation technique employed in analytical laboratories today, several new methods have become increasingly useful for specific applications. More recent techniques are examined and their differences, advantages and disadvantages are described in comparison with CID. Collisional activation upon impact of precursor ions on solid surfaces, surface‐induced dissociation (SID), is gaining importance as an alternative to gas targets and has been implemented in several different types of mass spectrometers. Furthermore, unique fragmentation mechanisms of multiply‐charged species can be studied by electron‐capture dissociation (ECD). The ECD technique has been recognized as an efficient means to study non‐covalent interactions and to gain sequence information in proteomics applications. Trapping instruments, such as quadrupole ion traps and Fourier transform ion cyclotron resonance instruments, are particularly useful for the photoactivation of ions, specifically for fragmentation of precursor ions by infrared multiphoton dissociation (IRMPD). IRMPD is a non‐selective activation method and usually yields rich fragmentation spectra. Lastly, blackbody infrared radiative dissociation is presented with a focus on determining activation energies and other important parameters for the characterization of fragmentation pathways. The individual methods are presented so as to facilitate the understanding of each mechanism of activation and their particular advantages and representative applications. Copyright © 2004 John Wiley & Sons, Ltd.
Effect of different sources of dietary omega‐3 fatty acids on general performance and fatty acid profiles of thigh, breast, liver and portal blood of broilers
Authors: Schreiner Matthias , Hulan Howard W , Razzazi‐Fazeli Ebrahim , Böhm Josef , Moreira Renata G
Published: October 2004

One hundred and sixty‐eight 1‐day‐old Cobb broiler chickens were randomly assigned to 12 broiler cages to determine the dietary effect of different sources of oils rich in long‐chain omega‐3 polyunsaturated fatty acids (LCω3PUFA). The following oils were added to the feed at a concentration of 12.5 g kg−1: a highly refined seal blubber oil (SBO) containing 225 g kg−1 LCω3PUFA; a fish oil (FO) concentrate containing >800 g kg−1 LCω3PUFA in the form of triglycerides; and an FO concentrate containing >600 g kg−1 LCω3PUFA in the form of ethyl esters. Fatty acid profiles of the breast and thigh meat were measured in order to determine the deposition of LCω3PUFA into the body tissues, whilst fatty acid profiles of the liver and the portal blood were taken in order to deduce consequences of the different ester forms on the absorption process. A triangular sensory evaluation was performed on the breast meat. The levels of LCω3PUFA in all tissues and the portal blood reflected the concentrations of LCω3PUFA in the diets. The sensory properties of the breast meat were negatively influenced by ethyl ester supplementation only. Copyright © 2004 Society of Chemical Industry
Langerhans cell histiocytosis with central nervous system involvement: Follow‐up by FDG‐PET during treatment with cladribine
Authors: Büchler Tomas , Cervinek Libor , Belohlavek Otakar , Kantorova Iva , Mechl Marek , Nebesky Tomas , Vorlicek Jiri , Adam Zdenek
Published: October 2004

The prognosis of patients with Langerhans cell histiocytosis (LCH) involving the central nervous system (CNS) is generally poor, despite reports of clinical responses to chemotherapy, surgery, and radiation. We report on a patient with a 20‐year history of relapsing multisystem LCH who developed progressive neuropsychiatric symptoms, including diplopia, ataxia, and mental deterioration. There was a regression of lesions in the brain stem and cerebellum following chemotherapy with cladribine (2‐CdA) as evidenced by positron emission tomography (PET) scans. In conclusion, our experience is encouraging for the use of cladribine in CNS LCH. PET may be a useful modality for the monitoring of CNS disease activity in LCH and provides additional information in comparison with NMR imaging. © 2004 Wiley‐Liss, Inc.
Primitive neuroectodermal tumor (PNET) of the uterus in a renal allograft patient: A case report
Authors: Peres Edward , Mattoo Tej K. , Poulik Janet , Warrier Indira
Published: October 2004

The incidence of malignancy after renal transplant has been reported to range from 4% to 18%. Tumors of the skin and lip tend to be the most common with non‐Hodgkin lymphoma comprising 20% of all neoplasms. Primitive neuroectodermal tumors (PNET) are collectively described as being a part of the Ewing sarcoma family of tumors. PNET occur more commonly in the second decade of life, predominantly affecting Whites and Hispanics, and rarely occur in individuals of African or Asian descent. The most common primary site of involvement is along the central axis, particularly the chest (Askin tumor), but it can arise in any soft tissue. PNET also occur in the head and neck. PNET involving the cervix, urinary bladder, uterus, and vagina have been reported. We describe a case of a 15‐year‐old female who, 9 years after receiving a living related renal transplant, developed a post‐transplant PNET of the uterus. © 2004 Wiley‐Liss, Inc.
Crystal morphology and crystallization kinetics of polyamide‐11/clay nanocomposites
Authors: Zhang Qin , Yu Min , Fu Qiang
Published: October 2004

Polyamide‐11 (PA11)/clay nanocomposites were prepared by in situ intercalative polymerization. The crystal morphology and crystallization kinetics of these nanocomposites were investigated via polarized light microscopy (PLM), small‐angle laser scattering (SALS) and differential scanning calorimetry (DSC). PA‐11 can crystallize into well‐formed spherulites, while only very tiny crystallites were observed by PLM and SALS for the nanocomposites. Both isothermal and non‐isothermal crystallization methods were employed to investigate the crystallization kinetics by DSC. Both techniques showed an increased crystallization rate with the addition of clay. However, the Avrami exponent decreased with the addition of clay in isothermal crystallization but showed a wide range of values depending on the cooling rate in the non‐isothermal crystallization. The changes in crystal morphology and crystallization kinetics can be understood as being due to the ‘supernucleating’ effect of the nanodispersed clay layers. Copyright © 2004 Society of Chemical Industry
Fabrication of conjugated polymer arrays by spinodal dewetting
Authors: Yan Lifeng , Yang Jinlong , Zhou Mi , Zhu Qingshi
Published: October 2004

Ordered arrays of conjugated poly(9,9‐dihexylfluorene) (PF) were prepared by the spinodal dewetting of liquid thin films on mica substrates. The size of the aggregates in the arrays was controlled by the evaporation rate of the solvent. Fast solvent evaporation resulted in smaller aggregates; slower evaporation resulted in larger aggregates. The photoluminescence of the PF arrays showed a smaller red‐shift than that of the unpatterned film when compared to PF solutions, which indicated that the aggregation of PF in the arrays is smaller than that in the unpatterned films. Copyright © 2004 Society of Chemical Industry
Structural characterization of α‐ and β‐nucleated isotactic polypropylene
Authors: Romankiewicz Anna , Sterzynski Tomasz , Brostow Witold
Published: October 2004

Modification of isotactic polypropylene (iPP) with two nucleation agents, namely 1,3:24‐bis(3,4‐dimethylobenzylideno) sorbitol (DMDBS) (α‐nucleator) and N, N′‐dicyclohexylo‐2,6‐naphthaleno dicarboxy amide (NJ) (β‐nucleator), leads to significant changes of the structure, morphology and properties. Both nucleating agents cause an increase in the crystallization temperature. The efficiency determined in a self‐nucleation test is 73.4 % for DMDBS and 55.9 % for NJ. The modification with NJ induces the creation of the hexagonal β‐form of iPP. The addition of DMDBS lowers the haze of iPP while the presence of NJ increases the haze. Copyright © 2004 Society of Chemical Industry
Epoxy resin based nanocomposites: 1. Diglycidylether of bisphenol A (DGEBA) with triethylenetetramine (TETA)
Authors: Brown Jane , Rhoney Ian , Pethrick Richard A
Published: October 2004

The preparation and properties of a series of nanocomposite materials obtained using different organically modified montmorillonite clays with a simple epoxy resin are reported. Dynamic mechanical thermal analysis is used to assess the effect of the incorporation of the clay platelets into the matrix of the polymer. In this system, it is observed that with the well‐dispersed clay system the low temperature modulus increases as would be predicted for a filled polymer system. The high temperature modulus increase is consistent with the premise that the polymer is interacting directly with the clay platelets. The glass transition temperature increases with the loading of the clay in the polymer resins. However, the extent to which enhancement of the physical properties of the composite occurs depends on the nature of the organic modifier. Copyright © 2004 Society of Chemical Industry
Bimodal polyethylene promoted by novel nickel complex
Authors: Tang Xiubo , Cui Yong , Sun Wen‐Hua , Miao Zhenjiang , Yan Shouke
Published: October 2004

A novel nickel complex, bis[2‐methyl‐2,4‐bis(2′‐pyridyl)‐1H‐1,5‐benzodiazepine]nickel dichloride, displayed good activity for oligomerization and polymerization of ethylene with the assistance of a co‐catalyst, methylaluminoxane (MAO). The oligomers were mainly olefins from C4 to C10, while the highly branched polyethylene (PE) had molecular weights (Mw) in the range 19 000–34 000. Bimodal distributions of the PE were clearly observed by both DSC and GPC measurements, while the spherulitic structure of the PE was shown in the morphology. Copyright © 2004 Society of Chemical Industry
Comparison of constitutive wheat bran tissues by dielectric spectroscopy and effect of their moisture content
Authors: Antoine Carole , Castellon Jerome , Toureille Alain , Rouau Xavier , Dissado Len
Published: October 2004

The dielectric properties of hand‐isolated wheat bran tissues (outer pericarp, intermediate and aleurone layers) were studied at 58 % and 75 % RH between 0.001 and 1E10 + 6 Hz. The measured values of the real and imaginary parts of bran tissue capacitances were modelled using an electrical circuit consisting of a constant phase angle component (CPA), a Warburg impedance and a parallel capacitance. The theoretical data from the equivalent circuit are in close agreement with the experimental values and allowed us to characterize the dielectric properties of the tissue. These results showed that the aleurone layer was the most capacitive tissue even though the outer pericarp exhibited the highest resistivity. Finally, tissue moisture contents were deduced from isotherm sorption measurements for a range of RH, and the water effect on their dielectric properties was analyzed. Copyright © 2004 Society of Chemical Industry
The effect of chemical heterogeneity on the properties of statistical copolymers: the conductivity of poly(aniline‐co‐2‐bromoaniline)
Authors: Stejskal Jaroslav
Published: October 2004

Chemical heterogeneity can influence the properties of statistical copolymers. It is shown that any integral property of a copolymer will depend on the chemical heterogeneity if such a property is a non‐linear function of copolymer composition. This is illustrated by means of the conductivity of copolymers of aniline and 2‐bromoaniline. The monomer reactivity ratios of this monomer pair are rA (aniline) = 0.94 and rB (2‐bromoaniline) = 0.31. The dependence of conductivity on the copolymer composition is non‐linear. Consequently, the conductivity depends on the compositional distribution, ie on the extent of chemical heterogeneity. Heterogeneous high‐conversion copolymers have lower conductivity than corresponding relatively homogeneous low‐conversion copolymers. The change in the average copolymer composition with increasing conversion is demonstrated for a copolymerization mixture containing 30 mol% aniline. The conductivity decreases at the same time as the chemical heterogeneity of the copolymer develops. The change in the average copolymer composition alone cannot explain the observed conductivity decrease. The conductivity is dependent not only on average composition but also on the chemical composition distribution. Copyright © 2004 Society of Chemical Industry
Space charge studies of crosslinked polyethylene midvoltage cable insulation by thermally stimulated depolarization current, infrared/Fourier transform infrared, and scanning electron microscopy
Authors: Tamayo I. , Belana J. , Diego J. A. , Cañadas J. C. , Mudarra M. , Sellarès J.
Published: October 2004

We studied the space charge behavior in crosslinked polyethylene cable insulation with thermally stimulated depolarization current (TSDC). The role of the semiconducting layers of the cable in space charge formation was determined with several experiments carried out with two different cables. TSDC spectra were obtained through the exchange of the semiconducting layers of each cable with aluminum or silver coatings. Heteropolar current peaks at 80 and 105 °C were observed in the TSDC spectrum. As a sample was annealed at high temperatures, the creation of traps in the material was promoted, and a homopolar contribution at 98 °C developed. This homopolar mechanism was linked to the diffusion, with annealing, of ionic components from the semiconducting layers into the insulation bulk. The penetration depth of these components was studied with Fourier transform infrared in sections obtained at several depths starting at the outer surface of the cable insulation. These diffused components remained on the crystal surfaces, and they became trapping centers for free charge. Charge injection from the semiconducting electrodes and homopolar trapping of injected charges on these components took place afterwards during polarization. This process tended to saturation. Besides this mechanism, the continuous dissociation of molecules took place in the material with thermal annealing. This ionic charge generation resulted in an increase in the heteropolar contribution of the TSDC spectrum. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4164–4174, 2004
Modeling loop reorganization free energies of acetylcholinesterase: A comparison of explicit and implicit solvent models
Authors: Olson Mark A.
Published: October 2004

The treatment of hydration effects in protein dynamics simulations varies in model complexity and spans the range from the computationally intensive microscopic evaluation to simple dielectric screening of charge‐charge interactions. This paper compares different solvent models applied to the problem of estimating the free‐energy difference between two loop conformations in acetylcholinesterase. Molecular dynamics (MD) simulations were used to sample potential energy surfaces of the two basins with solvent treated by means of explicit and implicit methods. Implicit solvent methods studied include the generalized Born (GB) model, atomic solvation potential (ASP), and the distance‐dependent dieletric constant. By using the linear response approximation (LRA), the explicit solvent calculations determined a free‐energy difference that is in excellent agreement with the experimental estimate, while rescoring the protein conformations with GB or the Poisson equation showed inconsistent and inferior results. While the approach of rescoring conformations from explicit water simulations with implicit solvent models is popular among many applications, it perturbs the energy landscape by changing the solvent contribution to microstates without conformational relaxation, thus leading to non‐optimal solvation free energies. Calculations applying MD with a GB solvent model produced results of comparable accuracy as observed with LRA, yet the electrostatic free‐energy terms were significantly different due to optimization on a potential energy surface favored by an implicit solvent reaction field. The simpler methods of ASP and the distance‐dependent scaling of the dielectric constant both produced considerable distortions in the protein internal free‐energy terms and are consequently unreliable. Proteins 2004. Published 2004 Wiley‐Liss, Inc.
Spin polarization and quantized conductance of ferromagnetic quantum point contacts
Authors: Li Yu‐Xian , Li Bo‐Zang
Published: October 2004

Spin polarization and conductance quantization of three‐dimensional ferromagnetic saddle‐point contacts under the influence of the molecular fields are studied. The results indicate that the molecular fields modify the quantized conductance and spin polarization, and the change is different for spin‐up and spin‐down electrons. The larger the molecular field, the higher is the degree of the spin polarization. Quantized conductance of odd integer multiples of appears and the spin degeneracy is removed, which agrees with the experiment. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoinduced second harmonic generation of LaFe4Sb12 near spin fluctuated critical points
Authors: Nouneh K. , Viennois R. , Kityk I. V. , Terki F. , Charar S. , Benet S. , Paschen S.
Published: October 2004

The temperature dependence of the resistivity, the Seebeck coefficient and photoinduced second harmonic generation (PISHG) are studied near the quantum critical point in the skutterudite compound LaFe4Sb12, possessing increased spin fluctuations. We observed a large maximum of the PISHG at a temperature of about 15 K. The PISHG signal increases substantially below 35 K. We found a correlation between the temperature dependences of PISHG, resistivity and Seebeck coefficient. We proposed a phenomenological explanation for the occurrence of the PISHG signal in LaFe4Sb12 implying strong spin fluctuations exist in this system, which may present some interest for the study of other spin fluctuation systems. Physical insight into the phenomenon observed is grounded in the participation of anharmonic electron–phonon and electron–paramagnon interactions stimulated by inducing light in the interactions with the photoexcited dipole moments. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron–phonon coupling and Jahn–Teller effect in KMgF3:Cr3+
Authors: Brik M. G. , Avram N. M. , Tanaka I.
Published: October 2004

Energy levels of the Cr3+ ion in the KMgF3 crystal are analyzed by means of the crystal field theory. Electron–phonon coupling constants (the Stokes shift, the force constants and the constants of the linear vibronic Hamiltonian) are evaluated using experimental spectroscopic data. The Jahn–Teller effect in the lowest excited 4T2g state of the Cr3+ ion is considered using both Ham effect and analysis of the displacements of ligands due to the combined effect of the a1g and eg normal modes of the [CrF6]3– octahedral complex. The net result of these vibrations for this cluster is an equatorial expansion by 0.070 Å and an axial compression by 0.008 Å. The value of the Jahn–Teller stabilization energy for the considered complex is about 357 cm−1. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic‐field‐induced polarization and magnetocapacitance in quantum paraelectric EuTiO3
Authors: Gong S. J. , Jiang Q.
Published: October 2004

EuTiO3 is a quantum paraelectric as well as an antiferromagnet. The most attractive property for EuTiO3 is the magnetoelectric coupling effect. In the present work, we investigate the influence of the external fields on EuTiO3, including the electric field E and magnetic field h. The application of the electric field counteracts the quantum fluctuation and forces the system into an electrically ordered state. The applied magnetic field directly induces the fluctuation of the spin‐pair correlation and indirectly influences the dielectric behaviors through the magnetoelectric coupling. In addition, we notice that the contribution of the magnetic field depends closely on the temperature condition and the electric field background. The (p, h, E, T) and (ε, h, T) diagrams are presented showing the temperature, magnetic and electric field dependence of the polarization and the dielectric capacitance. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrospray mass spectrometry studies of macromolecules containing 1,3‐oxazolidine moieties
Authors: Maślińska‐Solich J. , Gibas E.
Published: October 2004

The polycondensation of terephthalaldehyde with 2‐amino‐2‐methyl‐1,3‐propanediol using acidic catalysts leads to the formation of linear polymers and macrocyclic compounds with 2‐(1′,4′‐phenylene)‐5‐methyl‐1‐aza‐3,7‐dioxabicyclo[3.3.0]octane as the repeating unit in all compounds. The structure of the polymer was determined by 1H‐ and 13C‐NMR spectroscopy, and electrospray ionization mass spectrometric (ESI‐MS) analysis. ESI‐MS measurements were used to study the details of the polymer structure and support the equimolar alternating nature of bicyclo‐O,N‐acetals of terephthaldehyde in these macromolecules. Copyright © 2004 John Wiley & Sons, Ltd.
Utility of nonaqueous capillary electrophoresis for the determination of lidocaine and its metabolites in human plasma: a comparison of ultraviolet and mass spectrometric detection
Authors: Anderson Magnus S. , Lu Bing , Abdel‐Rehim Mohamed , Blomberg Sverker , Blomberg Lars G.
Published: October 2004

A nonaqueous capillary electrophoresis/electrospray mass spectrometry method for the separation of lidocaine (LID) and two of its metabolites, monoethylglycinexylidide (MEGX) and glycinexylidide (GX), has been developed. The separation medium was: 70 mM ammonium formate and 2.0 M formic acid in acetonitrile/methanol (60:40 v/v). With a sheath liquid of methanol/water (80:20 v/v) containing 2% formic acid and positive ion detection, reproducible determinations (8–11% relative standard deviation (RSD)) of lidocaine and its metabolites were performed in spiked human plasma. The limits of detection (LODs) were between 69.1 and 337 nM. The influences of sheath liquid composition, nebulizing gas pressure and drying gas temperature on the separation were examined. Copyright © 2004 John Wiley & Sons, Ltd.