bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of differently coated SPME fibres applied for monitoring volatile substances in vegetable oils
Authors: Doleschall Fruzsina , Recseg Katalin , Kemény Zsolt , Kővári Katalin
Published: June 2003

Cereol Group Center of Expertise, Budapest, Hungary Solid‐phase microextraction (SPME) was developed to determine volatile substances from liquid, gas or even solid materials. This technique has been successfully applied for soil, waste water, blood and urine samples, but in spite of its advantages there are still few applications for vegetable oils. SPME is applicable to determine the aroma and other volatile compounds of the oil, which are characteristic to its origin and oxidative status.

In this study the sensitivity and selectivity of some commercially available SPME adsorption materials (polydimethylsiloxane, divinylbenzene, carboxen) were compared. The diverse types of stationary phases were investigated by applying standard oils containing volatile substances from 9‐90 mg/kg concentrations.

SPME fibre was placed into the headspace of an oil sample in a 30‐ml headspace vial thermostated at 80 °C for 45 min. The extracted volatile materials were desorbed from the fiber in the injection port of the gas chromatograph at 250 °C. Identification of the extracted compounds is based on pure standards and mass spectra. The reliability of the SPME sampling method was studied by parallel measurements.

The 2‐cm long fibre coated with divinylbenzene (50 μm) and carboxen (30 μm) proved to be the most appropriate to determine the volatile oxo‐materials from vegetable oils. The method was successfully applied to follow up the formation of volatile substances (e.g. hexanal, t‐2‐hexenal, t‐2‐heptenal, t‐2‐octenal, nonanal, t, t‐2, 4‐nonadienal, t‐2‐nonenal, t‐2‐decenal, t, c‐ and t, t‐2, 4‐decadienal, 2‐pentylfuran, 1‐octen‐3‐ol) during deep frying in sunflower oil.
Evaluation of predictors of mortality in Frontotemporal Dementia—methodological aspects
Authors: Gräsbeck A. , Horstmann V. , Englund E. , Passant U. , Gustafson L.
Published: June 2003

Objectives

To retrospectively evaluate pre‐diagnostic clinical features (predictors) of mortality in frontotemporal dementia (FTD). The main aim was to investigate if there were indications against interpreting missing data as signs of absence.

Material and methods

96 cases with FTD, here defined as Dementia in Pick's disease according to ICD‐10. The predictors were behavioural/psychiatric features, language impairment and neurological deficits up to the date of diagnosis. Each predictor was rated as present (Yes), absent (No) or not recorded (Missing), and evaluated according to its distribution and mortality pattern: if a feature was not recorded because it was absent, the mortality of the Missing and the No‐category should hypothetically be close. Statistical methods included Kaplan‐Meier survival curves and Cox regression analyses.

Results

Neurological deficits and language impairments were frequently recorded as present or absent, while non‐recordings were more prevalent among the behavioural/psychiatric features. Some features were excluded as predictors because they showed too little variation. Analyses of the survival pattern indicated that in some features, the observations of the Missing‐category could be interpreted as absence of the symptoms. In other features these observations had to be regarded as truly missing.

Conclusions

In the retrospective evaluation of predictors of mortality a method for treating missing data was applied. The interpretation of non‐recordings as signs of absence was supported by the analyses of the survival patterns in some of the studied features. However, the study underscores the importance of systematic estimations of pre‐diagnostic clinical features in dementia. Copyright © 2003 John Wiley & Sons, Ltd.
Predictors of mortality in frontotemporal dementia: a retrospective study of the prognostic influence of pre‐diagnostic features
Authors: Gräsbeck A. , Englund E. , Horstmann V. , Passant U. , Gustafson L.
Published: June 2003

Objectives

To find associations between predictors and survival in frontotemporal dementia (FTD).

Methods

96 patients with FTD, here defined as Dementia in Pick's disease, were studied. The predictors included psychiatric/behavioural features, language impairment and neurological deficits present up to the time of diagnosis. The influence on mortality was studied by means of Cox regression analyses.

Results

Most of the behavioural/psychiatric features were associated with longer survival. Among these features, anxiety and suicidal ideation were associated with a statistically significant decreased mortality. Semi‐mutism/mutism and neurological deficits were associated with a statistically significant increased mortality. Analyses of the dementia‐specific mortality strengthened the already significant results and revealed dysphagia as significantly related to increased mortality.

Conclusions

Two groups of predictors with different influence on survival were identified in FTD. Most behavioural/psychiatric features were associated with longer survival. These features may indicate a slower disease progress and a better preserved cerebral function. By contrast, semi‐mutism/mutism, neurological deficits and dysphagia were associated with shorter survival, indicating an aggressive, degenerative process. Copyright © 2003 John Wiley & Sons, Ltd.
Factors associated with depression in a representative sample of 14 217 people aged 75 and over in the United Kingdom: results from the MRC trial of assessment and management of older people in the community
Authors: Osborn David P. J. , Fletcher Astrid E. , Smeeth Liam , Stirling Susan , Bulpitt Christopher J. , Breeze Elizabeth , Ng Edmond SW , Nunes Maria , Jones Dee , Tulloch Alistair
Published: June 2003

Background

Several social, demographic and physical factors have been shown to be associated with depression in later life, but results have been inconsistent. We aimed to assess factors associated with depression in old age, using data from the MRC trial of assessment and management of older people in the community.

Method

Analysis of cross‐sectional data. Depression was measured with a threshold of <6/6+ on the GDS‐15. Independent associations with social, demographic, physical and social network variables were assessed by logistic regression.

Results

In a fully adjusted analysis, odds ratios (OR) for depression were greater in older people, (adjusted OR for those aged 80–84 years = 1.1, 85–90 years = 1.5 and 90+ years = 1.8), those in rented (OR:1.3) or sheltered/residential accommodation (OR:1.5), and those widowed, divorced or separated (OR:1.2). Life events, (OR:1.4), smoking (OR:1.6), having two or more physical illnesses (OR:1.6) or no confiding relationship (OR:3.4) were also significantly associated with depression. Higher alcohol consumption was not predictive. Female sex and living alone were associated with depression in a crude analysis, but not after full adjustment for confounding.

Conclusions

The importance of these results lies in the large size and representative nature of the sample. In contrast to some previous reports, increasing age was associated with increasing risk of depression, but sex, living alone and alcohol were not associated. Social isolation was more important than living alone per se. Other associations largely concurred with previous work. Copyright © 2003 John Wiley & Sons, Ltd.
Process intensification in wastewater treatment: ferrous iron removal by a sustainable membrane bioreactor system
Authors: Pekdemir Turgay , Keskinler Bulent , Yildiz Ergun , Akay Galip
Published: June 2003

Biooxidation of ferrous iron (Fe2+) from strongly acidic industrial wastewater with a high Fe2+ content by Thiobacillus ferrooxidans in a packed bed reactor and subsequent removal of ferric iron (Fe3+) by a crossflow microfiltration (membrane) process have been investigated as functions of wastewater flowrate (54–672 cm3 h−1), Fe2+ concentration (1.01–8.06 g dm−3), and pH (1.5–5.0). A natural (vegetable) sponge, Luffa cylindrica, was used as support matrix material. The fastest kinetic performance achieved was about 40 g Fe2+ dm−3 h−1 at a true dilution rate of 19 h−1 corresponding to a hydraulic retention time of 3.16 min. Steady state conversion was observed to be about 10% higher at pH 2.3 than that at pH 1.5. Increasing the flowrate of the inlet wastewater caused a reduction in conversion rate. The oxidation rate reduced along the reactor height as the wastewater moved towards the exit at the top but conversion showed the opposite trend. Increasing Fe2+ concentration up to a critical point resulted in an increased oxidation rate but beyond the critical point caused the oxidation rate to decrease. Luffa cylindrica displayed suitable characteristics for use as a support matrix for formation of a Thiobacillus ferrooxidans biofilm and showed promising potential as an ecological and sustainable alternative to existing synthetic support materials. Membrane separation was shown to be a very effective means of Fe3+ removal from the wastewater with removal changing from 92% at pH 2.3 to complete removal at pH 5.0. Copyright © 2003 Society of Chemical Industry
Decomposition of 1,2‐dichloroethane in an RF plasma environment
Authors: Li Chun‐Teh , Yang Renbo , Shih Minliang , Chen Chuh‐Yung , Hsieh Lien‐Te
Published: June 2003

A radio frequency (RF) plasma system has been used to decompose 1,2‐dichloroethane (DCE). Final products were identified by a Fourier transform infrared (FTIR) spectrometer. The main products of DCE decomposition in O2/Ar plasma were CO2, CO, and HCl. Other minor chlorinated products were CCl4, C2HCl3, C2H3Cl, C2Cl4, CHCl3, C2HCl5, and COCl2. Nonchlorinated products were C2H2, C2H4, C2H6, and HCOOH. The plasma reactor with a brass electrode had a higher decomposition fraction of DCE [η, (Cin − Cout)/Cin × 100%] than that obtained with other materials (Au, Ni, and Cr). Different electrode configurations (inner and outer) were also evaluated for the decomposition of DCE. Argon plus oxygen was found to be the most suitable carrier/auxiliary gas for DCE decomposition. In addition, operational parameters for DCE decomposition in RF plasma including concentration, operational pressure, and total gas flow rate were evaluated. Copyright © 2003 Society of Chemical Industry
Studies of the interactions between the anticytokeratin 8 monoclonal antibody TS1, its antigen and its anti‐idiotypic antibody αTS1
Authors: Erlandsson Ann , Holm Patrik , Ullén Amanda , Stigbrand Torgny , Sundström Birgitta E.
Published: June 2003

The monoclonal antibody TS1 against cytokeratin 8 and its antiidiotype αTS1 have been used for immunotargeting and therapy of carcinomas in experimental tumor model systems. The interaction surfaces between mab TS1, the cytokeratin 8 epitope, and its anti‐idiotypic antibody, αTS1, were studied in detail in order to make future veneering of the interactions possible. The V‐genes of TS1 and αTS1 were cloned and sequenced and the CDRs and the framework residues were identified. Amino acids participating in the interactions were identified following chemical modifications of residues in non‐protected and protected molecules of cytokeratin 8, αTS1 and TS1. From the sequences, the three‐dimensional structures were generated using computer modelling of the antibody variable regions. Several charged amino acid, histidine and tyrosine residues were displayed in the antibody surfaces implicated in the interactions and chemical modification confirmed the importance of these amino acids. The cytokeratin 8 epitope has previously been identified by Johansson et al. and it displays negatively charged amino acid residues which could be identified in the chemical modification. It was also revealed that the TS1 binding to cytokeratin 8 and αTS1 respectively are partly overlapping; a histidine identified in TS1 is probably involved only in the interaction with αTS1. Furthermore, the chemical modification demonstrated that exchanging aspartic–glutamic acids to asparagine–glutamine residues in TS1 increased the binding of TS1 to cytokeratin 8, indicating that there is at least one acidic amino acid that is an obstacle in the TS1–CK8 binding. The detailed assembly of the interaction surfaces will facilitate the future use of site directed mutagenesis to improve the TS1–CK8 association rate and the clearing of TS1 with αTS1 in vivo. Copyright © 2003 John Wiley & Sons, Ltd.
Anti‐β2‐glycoprotein I antibodies recognizing platelet factor 4–heparin complex in antiphospholipid syndrome in patient substantiated with mouse Model
Authors: Bourhim Mustapha , Darnige Luc , Legallais Cécile , Arvieux Josiane , Cevallos Ramiro , Pouplard Claire , Vijayalakshmi Mookambeswaran A.
Published: June 2003

The antiphospholipid syndrome is defined by the presence of antiphospholipid antibodies associated with arterial and/or venous thrombosis, and recurrent abortion accompanied often by thrombocytopenia. These antibodies are heterogeneous and react against phospholipid‐binding proteins such as β2‐glycoprotein I (β2GPI) and prothrombin. The recognition of anti‐β2‐glycoprotein I (anti‐β2GPI) by platelet factor 4–heparin complex (PF4–Hc) has been previously evoked and partially confirmed by the present inhibition studies. Further, the anti‐β2‐glycoprotein I antibodies were purified from a patient with primary antiphospholipid syndrome using Affi‐gel®‐10‐β2GPI immunoaffinity chromatography. The purified anti‐β2GPI IgM as well as patient serum equally recognized PF4–Hc in ELISA mode. In order to substantiate this data and to better understand we studied an animal model using mouse active immunization with the purified human anti‐β2GPI. The mice showed a significant decrease in their platelet count. In addition the ELISA responses of the immunized mice sera were positive against both β2GPI and PF4–Hc, substantiating the double recognition. Despite many previous reported animal model studies, this is the first time we have shown the specific recognition of anti‐β2GPI antibodies by PF4–Hc, the results in the induced mice correlating the data observed with some patients. Copyright © 2003 John Wiley & Sons, Ltd.
Diabetic foot salvage with microsurgical free‐tissue transfer
Authors: Musharrafieh Ramzi , Saghieh Said , Macari George , Atiyeh Bechara
Published: June 2003

The efficacy of microsurgical free‐tissue transfer for the treatment of chronic nonhealing infected diabetic foot ulcers was evaluated in a retrospective study. Between January 1992–December 1997, 10 patients underwent surgery at the American University of Beirut. Muscular free flaps were used to salvage 8 feet, and fasciocutaneous free flaps were used in 2 feet. The flap survival rate was 90%, a result that is equivalent to other series of microvascular tissue transfer in nondiabetic patients; the postoperative morbidity rate was comparable to that of nondiabetic patients. Infection control was achieved in 87.5% of patients. Seven of the 9 surviving patients had bipedal gait and were ambulatory, with full weight‐bearing on their flaps at the end of the 2‐year follow‐up period. Microvascular free‐tissue transfer can be used successfully for the salvage of infected diabetic foot ulcers. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:257–261 2003
Serratus anterior‐rib free flap in limb bone reconstruction
Authors: Georgescu Alexandru V. , Ivan Ovidiu
Published: June 2003

The authors present their experience in surgical reconstruction of bone lesions in posttraumatic bone defects, pseudarthrosis, and osteitis by using the free serratus anterior‐rib flap. The flap was used in 12 cases: 7 cases in the upper limb, and 5 cases in the lower limb. The overall immediate success rate in our series was of 91.7%. We had only one failure, due to a venous thrombosis. In all successful cases, the rib showed good integration. This procedure seems to be very useful in the reconstruction of small and medium bone defects, especially in the upper limb. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:217–225 2003
Emergency free flaps
Authors: Georgescu Alexandru V. , Ivan Ovidiu
Published: June 2003

The use of top‐quality tissue in covering soft‐tissue loss, and precocity in reconstructing injuries and restoring function, are major prerequisites for obtaining a good surgical result. Earlier methods of reconstruction, based on a delay, for various periods of time, in reconstruction, have gradually become obsolete. The employment of more aggressive techniques and research supporting the “as‐early‐as possible” morphological and functional reconstruction path has become the rule in dealing with emergency reconstructive interventions. This path has been opened by data that describe and clarify the reaction of skin, muscles, and osteoarticular vascular anatomy to traumatic injury. This research, combined with the current availability of a great number of both simple and complex free flaps, has spurred the development of the concept of the “emergency free flap.” Here, the authors present a new classification of emergency free flaps, based on their experience using these procedures to treat traumatic injury. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:206–216 2003
One technique, two approaches, and results: Thoracic duct cannulation in small laboratory animals
Authors: Ionac Mihai
Published: June 2003

Experimental studies in immunology, pharmacology, or hematology require the sampling of the total thoracic duct lymph in awake and unrestrained rats or mice. Several approaches have been described for cannulation of the thoracic duct, but they are characterized by a modest reproducibility and a low lymph flow rate. An improved technique for obtaining thoracic duct lymph is described here, emphasizing the similarities and differences concerning both rats and mice (average weights of 305 and 15 g, respectively). Rats yielded a mean of 55.6 ml/day thoracic duct lymph, while lymph output in mice reached unexpected volumes of 29.3 ml/day. The use of an operating microscope and silicone cannula, and maintenance of mobility of the animals during lymph collection, offer a reliable method for a high and constant output of thoracic duct lymph. Relevant aspects of the murine thoracic duct anatomy are also identified. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:239–245 2003
Effect of degree of saponification on structural and property change of poly(Vinyl alcohol) fibers
Authors: Dai Lixing , Yu Shaoyong
Published: June 2003

To improve the drawability and finally the mechanical properties, poly(vinyl alcohol)s (PVA86, PVA93, and PVA99) with respective degrees of saponification of 86, 93, and 99% were synthesized using solution polymerization. Following the synthesis dimethylsulfoxide (DMSO) solutions of the PVAs were gel‐spun into methanol. After extraction of DMSO from the as‐spun fibers the dried fibers were first drawn at 120 °C then at 180 °C. An analysis of the structure and properties of the fibers was performed using FT‐IR, differential scanning calorimetry (DSC) and a fiber strength tester. The degree of saponification had an effect on the formation and intensity of the intermolecular hydrogen bonds, melting, drawability and strength of the PVA fibers. Low degrees of saponification weakened the intermolecular hydrogen bonds and interfered with the formation of crystallites, causing low melting points and low heat of fusion. Generally, drawing was easier to carry out at lower temperature, and higher draw ratios could be obtained, leading to higher fiber strengths. Copyright © 2003 John Wiley & Sons, Ltd.
Surface modification studies of Kapton® HN polyimide films
Authors: Huang Xu Dong , Bhangale Sunil Madhukar , Moran Peter M , Yakovlev Nikolai L , Pan Jisheng
Published: June 2003

Surface imide hydrolysis of Kapton HN polyimide films in a 1 M KOH aqueous solution was studied using dynamic contact angle measurements, X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS). The surface energy of Kapton HN increased quickly upon KOH treatment due to the formation of polar polyamate. Prolonged treatment led to a jump in surface energy that we ascribe to the onset of etching causing increased surface roughness. Potassium depth profiles of treated Kapton HN samples measured by XPS and TOF‐SIMS demonstrated that during the first 10 minutes of 1 M KOH treatment the modification depth increased rapidly. Thereafter the thickness of the modified layer no longer increased. For Kapton H films, however, the development of etching was much slower and a steady increase in modification depth was observed even after long treatment times. The different behaviours between Kapton HN and Kapton H films in alkali solutions are analysed and discussed. Copyright © 2003 Society of Chemical Industry
Effects of molecular interactions on the viscoelastic and plastic behaviour of plasticized poly(vinyl chloride)
Authors: Dubault A , Bokobza L , Gandin E , Halary JL
Published: June 2003

The mechanical behaviour of plasticized poly(vinyl chloride) in the glassy state was revisited in order to provide some understanding of the properties observed on the molecular scale. Nine samples were investigated, consisting either of pure poly(vinyl chloride) or of plasticized formulations including different amounts of di‐octyl phthalate or benzyl butyl phthalate in the range 5–20 wt%. Presence of the additives resulted in the depression of the glass transition temperature,Tg, and the main mechanical relaxation temperature,Tα, as determined by differential scanning calorimetry and dynamic mechanical analysis, respectively. These expected results were related to the plasticizing character of the additives on the long‐range cooperative polymer motions. In addition, a marked reduction of the secondary mechanical relaxation β was observed for additive concentrations equal to or larger than 10 wt%. This antiplasticizing effect was interpreted as the hindrance of main‐chain local polymer motions, due to poly(vinyl chloride)–additive interactions. Occurrence of such interactions was confirmed by mid‐ and near‐infrared measurements. The plastic behaviour of the materials in the glassy state was also examined. Particular attention was paid to the strain‐softening amplitude (difference between yield stress and plastic flow stress), to the percentage of non‐elastic deformation and to the mechanical energy to yield. All these quantities are strongly affected by the chain‐mobility characteristics. Copyright © 2003 Society of Chemical Industry
Hydroxyapatite as a filler for biosynthetic PHB homopolymer and P(HB–HV) copolymers
Authors: Bergmann Antje , Owen Anthony
Published: June 2003

This paper deals with some of the fundamental problems encountered when using a semicrystalline polymer as the matrix phase for a particulate‐filled composite. As our model system we adopted poly‐(R)‐3‐hydroxybutyrate, PHB, and two copolymers of (R)‐3‐hydroxybutyrate and (R)‐3‐hydroxyvalerate, P(HB–HV), for the matrix phase, and the mineral calcium hydroxyapatite as a particulate filler. The structure and properties of compression‐moulded films of various compositions were investigated by polarized light microscopy, wide‐angle X‐ray scattering and mechanical testing. It was found that the degree of crystallinity of the matrix was lower in filled samples, and that the spherulitic crystallization of the matrix appeared to cause the filler particles to form agglomerates, which would not be as effective a reinforcement as finely dispersed primary filler particles. The tensile strength, strain‐to‐break and tensile modulus of samples of different compositions were analysed using well‐known theories for composite behaviour. Copyright © 2003 Society of Chemical Industry
Photo‐induced birefringence phenomenon of a double azo polymer
Authors: Wang Jian , Zhang LingZhi , Niu Yongping , Liang Zhaoxi , Chen Yonglie , Huang Yaping , Wang Hui , Lin Weizhu
Published: June 2003

Poly(glycidyl methacrylate) grafted with double azo bond 4[4′‐(phenylazo)phenylazo]phenol was synthesized and characterized. Photo‐induced birefringence phenomenon of this polymer was studied by static absorption and dynamic pump‐probe techniques, and was compared with that of another polymer Poly{(methyl methacrylate)‐co‐4‐[(3‐methacryloyloxy)} [P(MMA‐co‐MAZ)] containing mono azobenzene chromophore. The results showed that former polymer carrying two azo bonds, with a larger birefringence ratio, had a relatively faster optical switching response than the latter polymer under the same pump beam power. Copyright © 2003 Society of Chemical Industry
Magnetic and conducting Fe3O4–polypyrrole nanoparticles with core‐shell structure
Authors: Deng Jianguo , Peng Yuxing , He Chuanlan , Long Xingping , Li Pei , Chan Albert S C
Published: June 2003

Magnetic and conducting Fe3O4–polypyrrole nanoparticles with core‐shell structure were prepared in the presence of Fe3O4 magnetic fluid in aqueous solution containing sodium dodecylbenzenesulfonate (NaDS) as a surfactant and dopant. Both the conductivity and magnetization of the composites depend strongly on the Fe3O4 content and the doping degree. With increase of Fe3O4 content in the composite, the conductivity at room temperature decreases, but the saturated magnetization and coercive force increase. Transmission electron microscopy (TEM) images of Fe3O4 and Fe3O4–polypyrrole particles show almost spherical particles with diameters ranging from 20 to 30 and 30 to 40 nm, respectively. The thermal stability of Fe3O4–polypyrrole composites is higher than that of pure polypyrrole. Studies of IR, UV–visible and X‐ray photoelectron spectroscopy (XPS) spectra suggest that the increased thermal stability may be due to interactions between Fe3O4 particles and polypyrrole backbone. Copyright © 2003 Society of Chemical Industry
Role of hydrogen bonding in the oxidation potential of enols
Authors: Lal Mukul , Langels Anja , Deiseroth Hans‐Jörg , Schlirf Jens , Schmittel Michael
Published: June 2003

Three stable β,β‐dimesityl enols with heteroaromatic rings in the α‐position were synthesized to study the effect of OH···N hydrogen bonding on the oxidation potentials of enols. In contrast to its solid‐state structure, enol E1 exists predominantly as intramolecularly hydrogen‐bonded species in solution. For enol E2 an intermolecular hydrogen bond and for E3 a partial proton transfer were established based on NMR, dilution experiments, solvent dependence and UV–visible spectroscopic studies. Cyclic voltammetric investigations revealed that OH···N hydrogen bonding may shift the oxidation potentials of enols by up to 510 mV cathodically. Copyright © 2003 John Wiley & Sons, Ltd.
Residual thermal birefringence in freely quenched plates of amorphous polymers: Simulation and experiment
Authors: Shyu G. D. , Isayev A. I. , Li C. T.
Published: June 2003

Free quenching experiments were performed on thin plates of polystyrene (PS) and polycarbonate (PC). The thermal birefringence distribution along the thickness direction of the plates was measured. The birefringence data were compared with the results of a numerical simulation based on the linear viscoelastic and photoviscoelastic constitutive equations for the mechanical and optical properties, respectively, and the first‐order rate equation for volume relaxation. The effects of the initial temperature, quenching temperature, and quenching media on the development of residual thermal stresses and birefringence were evaluated. At higher initial temperatures (>105 °C), the thermal birefringence in quenched PS plates was negative at the center and positive at the surface, whereas at lower temperatures (close to the glass‐transition temperature), the birefringence became positive at the core and negative at the surface or positive through the entire cross section of the plate. The birefringence in freely quenching PC plates was positive at the center and negative at the surface at any initial temperature. These observations were in fair agreement with predicted data. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1850–1867, 2003
Intersecting branes and 7‐manifolds with G2 holonomy
Authors: Behrndt K.
Published: June 2003

In this talk I discuss intersecting brane configurations coming from explicit metrics with G2 holonomy. An example of a 7‐manifold which representing a \documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}$\mathbb R^3$\end{document} bundle over a self‐dual Einstein space is described and the potential appearing after compactification over the 6‐d twistor space is derived.
M‐theory on manifolds with exceptional holonomy
Authors: Gukov S.
Published: June 2003

In this lecture I review recent progress on construction of manifolds with exceptional holonomy and their application in string theory and M‐theory.
Local intersecting brane worlds
Authors: Uranga A.M.
Published: June 2003

We describe the construction of configurations of D6‐branes wrapped on compact 3‐cycles intersecting at points in non‐compact Calabi‐Yau threefolds. Such constructions provide local models of intersecting brane worlds, and describe sectors of four‐dimensional gauge theories with chiral fermions. We present several classes of non‐compact manifolds with compact 3‐cycles intersecting at points, and several explicit examples of these constructions, some of which have Standard Model like gauge group and three quark‐lepton generations. In some cases, mirror symmetry relates the models to other constructions used in phenomenological D‐brane model building, like D‐branes at singularities.
PHOSPHORUS PLACEMENT ON ACID ARENOSOLS OF THE WEST AFRICAN SAHEL
Authors: MUEHLIG-VERSEN B. , BUERKERT A. , BATIONO A. , ROEMHELD V.
Published: June 2003

Phosphorus (P) deficiency is a major constraint to pearl millet (Pennisetum glaucum L.) growth on acid sandy soils of the West African Sahel. To develop cost-effective fertilization strategies for cash poor farmers, experiments with pearl millet were conducted in southwestern Niger. Treatments comprised single superphosphate hill-placed at rates of 1, 3, 5 or 7 kg P ha−1 factorially combined with broadcast P at a rate of 13 kg ha−1. Nitrogen was applied as calcium ammonium nitrate at rates of 30 and 45 kg ha−1. At low soil moisture, placement of single superphosphate in immediate proximity to the seed reduced seedling emergence. Despite these negative effects on germination, P placement resulted in much faster growth of millet seedlings than did broadcast P. With P application, potassium nutrition of millet was improved and seedling nitrogen uptake increased two- to three-fold, indicating that nitrogen was not limiting early millet growth. Averaged over the 1995 and 1996 cropping seasons, placed applications of 3, 5 and 7 kg P ha−1 led to 72%, 81% and 88% respectively, of the grain yield produced by broadcasting 13 kg P ha−1. Nitrogen application did not show major effects on grain yield unless P requirements were met. A simple economic analysis revealed that the profitability of P application, defined as additional income per unit of fertilizer, was highest for P placement at 3 and 5 kg ha−1.
Short cut fusion is correct
Authors: JOHANN PATRICIA
Published: June 2003

Fusion is the process of removing intermediate data structures from modularly constructed functional programs. Short cut fusion is a particular fusion technique which uses a single, local transformation rule to fuse compositions of list-processing functions. Short cut fusion has traditionally been treated purely syntactically, and justifications for it have appealed either to intuition or to “free theorems” – even though the latter have not been known to hold in languages supporting higher-order polymorphic functions and fixpoint recursion. In this paper we use Pitts' recent demonstration that contextual equivalence in such languages is parametric to provide the first formal proof of the correctness of short cut fusion for them. In particular, we show that programs which have undergone short cut fusion are contextually equivalent to their unfused counterparts.
Epitope mapping for the monoclonal antibody that inhibits intramolecular electron transfer in flavocytochrome b2
Authors: LÊ K. H. Diêp , MAYER Martine , LEDERER Florence
Published: June 2003

Flavocytochrome b2 (yeast l-lactate dehydrogenase) carries one FMN and one protohaem IX on each of its four subunits. The prosthetic groups are bound to separate domains, the haem domain (residues 1–99) and the flavin domain (residues 100–485), which interact for electron transfer between lactate-reduced FMN and haem b2; in vivo, the latter reduces cytochrome c. In the crystal structure, one haem domain out of two is mobile. Previously we have described a monoclonal antibody, raised against the tetramer, that only recognizes the native haem domain and prevents electron transfer between flavin and haem, while having no effect on flavin reduction by the substrate [Miles, Lederer and Lê (1998) Biochemistry 37, 3440–3448]. In order to understand the structural basis of the uncoupling between the domains, we proceeded to site-directed mutagenesis, so as to map the epitope on the surface of the haem domain. We analysed the effects of 14 mutations at 12 different positions, located mostly in the domain interface or at its edge; we also analysed the effect of replacing protohaem IX with its dimethyl ester. We used as criteria the antibody-mediated inhibition of cytochrome c reduction by flavocytochrome b2, competitive ELISA tests and surface plasmon resonance. We have thus defined a minimal epitope surface on the haem domain; it encompasses positions 63, 64, 65, 67, 69 and 70 and one or both haem propionates. When the haem and flavin domains are docked for electron transfer, the 65, 67 and 70 side chains, as well as the haem propionates, are excluded from solvent. The present results thus indicate that, when bound, the antibody acts as a wedge between the domains and constitutes a physical barrier to electron transfer.
Discrepancies between ecological and individual data on fruit and vegetable consumption in fifteen countries
Authors: Pomerleau Joceline , Lock Karen , McKee Martin
Published: June 2003

Although food supply statistics are commonly used in ecological studies of diet and disease, little information is available on how they compare with reported intakes of foods. The objective of the present study was to compare fruit and vegetable availability with estimates of national mean intakes derived from national food consumption surveys. Food availability statistics from the FAO were used. For each country, mean national supply, based on at least 3 years of FAO data, was calculated. National estimates of mean fruit and vegetable intakes were derived from population-based surveys from fifteen countries, gathered for the World Health Organization Global Burden of Disease Study revision for 2000. Extrapolations were made when survey data did not cover all age groups. For each country, the FAO:survey estimate ratio was calculated. This ratio ranged from 0·93 to 2·70 (median value=1·39). Although there was a tendency for FAO data to overestimate intakes (fourteen out of fifteen countries), the degree of overestimation varied greatly among the countries included in this study (5–270 %). As food supply statistics are the only source of information on dietary patterns in most countries of the world, further information on how they reflect food intakes is needed. Obtaining detailed and valid estimates of dietary intakes in more countries around the world will be essential for such comparisons.
RECONSTRUCTING GENERALIZED EXPONENTIAL LAWS BY SELF-SIMILAR EXPONENTIAL APPROXIMANTS
Authors: GLUZMAN S. , SORNETTE D. , YUKALOV V. I.
Published: June 2003

We apply the technique of self-similar exponential approximants based on successive truncations of simple continued exponentials to reconstruct functional laws of the quasi-exponential class from the knowledge of only a few terms of their power series. Comparison with the standard Padé approximants shows that, in general, the self-similar exponential approximants provide significantly better reconstructions.
A GENERALIZED JAYNES–CUMMINGS MODEL: NONLINEAR DYNAMICAL SUPERALGEBRA u(1/1) AND SUPERCOHERENT STATES
Authors: DAOUD M. , DOUARI J.
Published: June 2003

The generalization of the Jaynes–Cummings (GJC) Model is proposed. In this model, the electromagnetic radiation is described by a Hamiltonian which generalizes the harmonic oscillator to take into account some nonlinear effects which can occur in the experimental situations. The dynamical superalgebra and supercoherent states of the related model are explicitly constructed. Relevant quantities (total number of particles, energy and atomic inversion) are computed.
TOWARDS EXACT RESULTS IN NODAL ANTIFERROMAGNETIC PLANAR LIQUIDS
Authors: ALEXANDRE J. , MAVROMATOS N. E. , SARKAR SARBEN
Published: June 2003

It has been argued in previous works by the authors that nodal excitations in (2 + 1)-dimensional doped antiferromagnets might exhibit, in the spin-charge separation framework and at specific regions of the parameter space, a supersymmetry between spinons and holons. This supersymmetry has been elevated to a N = 2 extended supersymmetry of composite operators of spinon and holons, corresponding to the effective "hadronic" degrees of freedom. In this work we elaborate further on this idea by describing in some detail the dynamics of a specific composite model corresponding to an Abelian Higgs model (SQED). The Abelian nature of the gauge group seems to be necessitated both by the composite structure used, and also by electric charge considerations for the various composites. We demonstrate the passage from a pseudogap to an unconventional superconducting phase, which notably is an exact non-perturbative analytic result, due to the underlying N = 2 supersymmetric Abelian gauge theory. We believe that these considerations may provide a first step towards a non-perturbative understanding of the phase diagrams of strongly-correlated electron systems.
ON THE STRUCTURE OF THE SOLUTIONS OF A TWO-PARAMETER FAMILY OF THREE-DIMENSIONAL ORDINARY DIFFERENTIAL EQUATIONS
Authors: IMPRAM SERKAN T. , JOHNSON RUSSELL , PAVANI RAFFAELLA
Published: June 2003

We analyze the global structure of the solutions of a three-dimensional, autonomous ordinary differential equation which depends on two parameters. We use graphical, heuristic, and rigorous arguments to show that as the parameters vary, a wide range of dynamical behavior is displayed.
TRANSIENT CHARACTERISTICS BETWEEN PERIODIC ATTRACTORS STABILIZED BY CHAOS CONTROL IN A SEMICONDUCTOR LASER
Authors: UCHIDA A. , SATO T. , YOSHIMORI S. , KANNARI F.
Published: June 2003

We investigate the transient response time between periodic attractors stabilized by chaos control methods in a semiconductor laser. We use the revised occasional proportional feedback (ROPF) method to shorten the transient response time and compare it with the high frequency injection (HFI) method. A chaotic attractor is stabilized resulting in two different periodic attractors (period-1 and period-6) under different control parameters, and the transient response time is measured as one of the stabilized periodic attractors is switched to the other. During the transition, the trajectory approaches a certain unstable periodic orbit (UPO), and the distance between the trajectory in the phase space and the UPO can be described as an exponential function of the transient response time. Since the trajectory can directly converge into the periodic orbit by using the ROPF method, the transient response time obtained by the ROPF method can be shortened more than that obtained by the HFI method.
THE SPREAD AND EXTREME TERMS OF JONES POLYNOMIALS
Authors: BAE YONGJU , MORTON HUGH R.
Published: June 2003

We adapt Thistlethwaite's alternating tangle decomposition of a knot diagram to identify the potential extreme terms in its bracket polynomial, and give a simple combinatorial calculation for their coefficients, based on the intersection graph of certain chord diagrams.
HIGHER DIMENSIONAL SPACE–TIME MODEL FOR A DUST-FILLED UNIVERSE WITH A COSMOLOGICAL CONSTANT
Authors: CHAKRAVARTY NABAJIT , SANTRA BATUL CHANDRA , CHAKRABORTY SUBENOY
Published: June 2003

In recent years it is generally believed that we should consider positive vacuum energy density or cosmological constant. Also as higher dimensional theory is important at the early stages of the Universe, so it will be interesting to study classical tests of cosmology in a higher dimensional generalized Kantowski–Sachs model. For matter field, we consider dust and a cosmological constant and examine which are physically permissible.
FULL CAUSAL BULK VISCOUS COSMOLOGIES WITH TIME-VARYING CONSTANTS
Authors: BELINCHÓN JOSÉ ANTONIO , CHAKRABARTY INDRAJIT
Published: June 2003

We study the evolution of a flat Friedmann–Robertson–Walker Universe, filled with a bulk viscous cosmological fluid, in the presence of time varying "constants." The dimensional analysis of the model suggests a proportionality between the bulk viscous pressure of the dissipative fluid and the energy density. Using this assumption and with the choice of the standard equations of state for the bulk viscosity coefficient, temperature and relaxation time, the general solution of the field equations can be obtained, with all physical parameters having a power-law time dependence. The symmetry analysis of this model, performed using Lie group techniques, confirms the uniqueness of the solution for this functional form of the bulk viscous pressure. In order to find another possible solution we relax the hypotheses and assume a concrete functional dependence for the "constants."
FRACTAL CHARACTER OF STOCK PRICE-VOLUME RELATION AND REGULATION OF STOCK PRICE MANIPULATION
Authors: ZHOU FENG , CHEN RONGQIU , XIA XINPING
Published: June 2003

We construct indexes of the price-volume relation and calculate correlation dimensions, based on the Fractal Market Hypothesis (FMH). According to this result, we propose a new method for the detection of stock price manipulation on the secondary market in China. The result of empirical research indicates: the great change of the stock price alone is insufficient to prove that there is stock price manipulation. However, the drastic fluctuations of correlation dimensions indicate the instability of the secondary market; and especially, the sudden drop of the correlation dimensions always means that there are stock manipulations on the market.
STRUCTURED AND FRACTAL SMOKE PATTERNS IN A SIMPLE CAVITY
Authors: CASTREJÓN PITA A. A. , CASTREJÓN PITA J. R. , HUELSZ G.
Published: June 2003

While conducting a study with air in a simple closed rectangular cavity, we have discovered the formation of highly impressive, complex-structured, and symmetrical smoke density patterns. Using the box counting method the fractal characteristic of the patterns is demonstrated.
PROFILES FRACTAL CHARACTERIZATION BY FREQUENCY ANALYSIS
Authors: PANCORBO MANUEL , ANGUIANO ELOY , AGUILAR MIGUEL
Published: June 2003

A discussion of the different methods for fractal profiles generation and of the methods for fractal characterization of profiles by frequency analysis is made in the whole range (1 < D < 2). We obtain the conclusion that all methods for measurement of fractal dimension that has been proposed are doubtful.
HOW DYNAMIC AGGREGATES MAY ACHIEVE EFFECTIVE INTEGRATION
Authors: EARLEY JOSEPH E.
Published: June 2003

Requirements for warranted identification of 'emergence' of new entities in nonlinear chemical dynamic systems are considered in terms of developments in both chemistry and in philosophy. In particular, a recently reported example of emergence of coherence in a set of electrochemical oscillators is examined. The philosophical theory of 'response dependence,' proposed as a 'third way' in the realist-antirealist controversy, and a contemporary discussion of the concept of substance are also employed. The conclusion is reached that when a set of chemical reactions achieves such closure as to generate persistent and interactive coherence (such as a limit cycle or strange attractor), properties of a test entity are altered. To the extent that this can be shown to be the case, it is appropriate to consider that a novel (emergent) entity has come into existence. Existence of the limit cycle brings about major changes in the levels (concentrations) of reactants that generate that cycle. Emergent entities of the type discussed in this paper are not adequately dealt with by the standard philosophical theory of wholes and part ('mereology'). That theory should be extended or modified.
Intra‐ and inter‐fractional variations of tumors with fiducial markers measured using respiratory‐correlated computed tomography images for respiratory gated lung stereotactic body radiation therapy
Authors: Manabe Yuki , Shiinoki Takehiro , Fujimoto Koya , Ueda Kazushi , Karita Masako , Ono Taiki , Kajima Miki , Tanaka Hidekazu
Published: January 2024

Purpose

This study evaluated the intra‐ and inter‐fractional variation of tumors with fiducial markers (FMs), relative to the tumor‐FM distance, to establish how close an FM should be inserted for respiratory‐gated stereotactic body radiation therapy (RG‐SBRT).

Methods

Forty‐five lung tumors treated with RG‐SBRT were enrolled. End‐expiratory computed tomography (CT) (CTplan) and four‐dimensional‐CT (4D‐CT) scans were obtained for planning. End‐expiratory CT (CTfr) scanning was performed before each fraction. The FMs were divided into two groups based on the median tumor‐FM distance in the CTplan (Dp). For the intra‐fractional variation, the correlations between the corresponding tumor and FM intra‐fractional motions, defined as the centroid coordinates of those in each 0–90% phase, with the 50% phase of 4D‐CT as the origin, were calculated in the left‐right, anterior‐posterior, and superior‐inferior directions. Furthermore, the maximum difference in the tumor‐FM distance in each phase of 4D‐CT scan, based on those in the 50% phase of 4D‐CT scan (Dmax), was obtained. Inter‐fractional variation was defined as the maximum distance between the tumors in CTplan and CTfr, when the CT scans were fused based on each FM or vertebra.

Results

The median Dp was 26.1 mm. While FM intra‐fractional motions were significantly and strongly correlated with the tumor intra‐fractional motions in only anterior‐posterior and superior‐inferior directions for the Dp > 26 mm group, they were significantly and strongly correlated in all directions for the Dp ≤ 26 mm group. In all directions, Dmax values of the Dp ≤ 26 mm group were lower than those of the Dp > 26 mm group. The inter‐fractional variations based on the Dp ≤ 26 mm were smaller than those on the Dp > 26 mm and on the vertebra in all directions.

Conclusions

Regarding intra‐ and inter‐fractional variation, FMs for Dp ≤ 26 mm can increase the accuracy for RG‐SBRT.
Multilateral Sound Manipulation Using Magnetically Tunable Apertures
Authors: Bansal Shubhi , Choi Christabel , Subramanian Sriram
Published: January 2024

In recent years, planar aperture‐based acoustic devices have been investigated due to their thin form factor, high effective transmission, and sound modulation capability. Moreover, reconfigurable and tunable devices are being continuously researched to enable multiple degrees of freedom in real time. Herein, an aperture‐based acoustic device is presented, which enables tunable multilateral ultrasonic operation. Sound waves are manipulated in multiple directions by continuously tuning aperture width or length, using a magnetically controlled rod. The position, orientation, and geometrical properties of the rod (i.e., length, topographical curvature) are exploited to create a varied interface for the impinging sound. Through experiments and simulations, acoustic wave steering in different orthogonal planes and acoustic switching using a single tunable device unit are demonstrated. Furthermore, different four‐unit device configurations are implemented for tunable beam‐formation and tunable acoustic focusing applications by utilizing the acoustic anisotropy of the system. The tunable dynamic acoustic device is scalable to audible frequencies and enables tilted operation. This straightforward and accessible proof‐of‐concept opens a paradigm for exploring multifunctional aperture‐based designs with greater degrees of freedom, bringing us a step closer toward practical applications such as acoustic device integration with walls, window panels, and other commercial products for tunable sound transmission.