bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyamines as olfactory stimuli in the goldfish Carassius auratus
Authors: Rolen S. H. , Sorensen P. W. , Mattson D. , Caprio J. 
Published: April 2003

SUMMARY
Electrophysiological responses of goldfish olfactory receptor neurons(ORNs) and goldfish behavioral responses to polyamines were investigated in vivo. Electro-olfactogram (EOG) recordings indicated that polyamines (putrescine, cadaverine and spermine) are potent olfactory stimuli for goldfish with estimated electrophysiological thresholds of 10–8–10–7 mol l–1,similar to that for L-arginine, the most stimulatory amino acid. Although thresholds were similar, the magnitude of the EOG responses to intermediate(10–5–10–4 mol l–1)and high (10–3 mol l–1) concentrations of polyamines dwarfed the responses to amino acids and related single amine containing compounds (amylamine and butylamine). The EOG responses to 0.1 mmol l–1 putrescine, cadaverine and spermine were, respectively,4.2×, 4.3× and 10.3× the response of the standard, 0.1 mmol l–1 L-arginine. Electrophysiological cross-adaptation experiments indicated that polyamine receptor sites are independent from those to L-amino acids (alanine, arginine, glutamate, lysine, methionine and ornithine), bile salts (sodium taurocholate and taurolithocholate), the single amine containing compounds (amylamine and butylamine) and ATP. Further, the cross-adaptation experiments revealed the existence of independent receptor sites for the different polyamines tested. Pharmacological experiments suggested that polyamine odorant transduction does not primarily involve the cyclic AMP and IP3 second messenger pathways. Behavioral assays indicated that polyamines are attractants that elicit feeding behavior similar to that elicited by L-amino acids.
Thermal windows on the trunk of hauled-out seals: hot spots for thermoregulatory evaporation?
Authors: Mauck Björn , Bilgmann Kerstin , Jones Daryl D. , Eysel Ulf , Dehnhardt Guido 
Published: April 2003

SUMMARY
Seals have adapted to the high heat transfer coefficient in the aquatic environment by effective thermal insulation of the body core. While swimming and diving, excess metabolic heat is supposed to be dissipated mainly over the sparsely insulated body appendages, whereas the location of main heat sinks in hauled-out seals remains unclear. Here, we demonstrate thermal windows on the trunk of harbour seals, harp seals and a grey seal examined under various ambient temperatures using infrared thermography. Thermograms were analysed for location, size and development of thermal windows. Thermal windows were observed in all experimental sessions, shared some common characteristics in all seals and tended to reappear in similar body sites of individual seals. Nevertheless, the observed variations in order and location of appearance,number, size and shape of thermal windows would imply no special anatomical site for this avenue of heat loss. Based on our findings, we suggest that, in hauled-out seals, heat may be transported by blood flow to a small area of the wet body surface where the elevation of temperature facilitates evaporation of water trapped within the seals' pelages due to increased saturation vapour pressure. The comparatively large latent heat necessary for evaporation creates a temporary hot spot for heat dissipation.
A female case of Sedaghatian type spondylometaphyseal dysplasia
Authors: Foulds Nicola , Fairhurst Jo , Temple I. Karen , Cade Steven , Groves Charlotte , Lancaster Tessa 
Published: April 2003

AbstractSedaghatian type spondylometaphyseal dysplasia is a rare osteochondrodysplasia first described in 1980. The original report describes an Iranian infant with mild rhizomelic limb shortening, severe metaphyseal cupping and irregularity and platyspondyly who died shortly after birth. The baby was born to a consanguineous couple who had reportedly had two similarly affected infants, one male and one female. No documented radiology is available on the female infant. Since this publication, 10 further case reports of male infants with this condition have appeared in the literature all of whom have died shortly after birth. We report a fully documented female case of Sedaghatian type spondylometaphyseal dysplasia providing further evidence to support an autosomal recessive mechanism of inheritance. © 2003 Wiley‐Liss, Inc.
Portal hypertension in Williams syndrome: Report of two patients
Authors: Casanelles Miguel Del Campo , Gil‐Fernández Juan José , Casero Luis F. Magano , Bengoechea Manuel García , Serrano Rosario , Rañada José María Fernández , Jurado Luis Alberto Pérez 
Published: April 2003

AbstractWilliams or Williams‐Beuren syndrome (WBS) is a developmental disorder with multisystemic manifestations characterized by distinctive facial features, mental disability with unique cognitive and personality profiles, vascular stenoses, growth retardation, and occasional infantile hypercalcemia, caused by haploinsufficiency for genes deleted in chromosome band 7q11.23. However, with the exception of arterial stenoses caused by haploinsufficiency for the elastin gene (ELN), no specific implication of any other gene in the phenotype has been established. We present two patients with portal hypertension leading to splenomegaly and pancytopenia carrying the common 1.5 Mb WBS deletion. We propose this is an additional severe vascular complication of ELN deficiency and discuss the specific characteristics of the portal venous tract that could explain the impact of ELN deficiency in that venous territory. This complication is potentially lethal and should thus be considered in any patient with WBS and splenomegaly. © 2003 Wiley‐Liss, Inc.
Deletion 12q: A second patient with 12q24.31q24.32 deletion
Authors: Plotner Pamela L. , Smith Janice L. , Northrup Hope 
Published: April 2003

AbstractWe report on a 20‐month‐old patient with facial dysmorphisms, microcephaly, cardiac septal defects, global developmental delay, and failure to thrive. Karyotypic evaluation revealed an interstitial deletion of the long arm of one chromosome 12, del(12)(q24.31q24.32). Only one other patient with a similar deletion has been reported previously. By comparing the two patients, we can begin to identify a characteristic phenotypic pattern. © 2003 Wiley‐Liss, Inc.
Bayes' theorem in paleopathological diagnosis
Authors: Byers Steven N. , Roberts Charlotte A. 
Published: April 2003

AbstractThe utility of Bayes' theorem in paleopathological diagnoses is explored. Since this theorem has been used heavily by modern clinical medicine, its usefulness in that field is described first. Next, the mechanics of the theorem are discussed, along with methods for deriving the prior probabilities needed for its application. Following this, the sources of these prior probabilities and their accompanying problems in paleopathology are considered. Finally, an application using prehistoric rib lesions is presented to demonstrate the utility of this method to paleopathology. Am J Phys Anthropol 121:000–000, 2003. © 2003 Wiley‐Liss, Inc.
Synthesis and characterization of some dibutylbis{5‐[(E)‐2‐(aryl)‐1‐diazenyl]‐2‐hydroxybenzoato}tin(IV) compounds. Toxicity studies of di‐ and tri‐organotin complexes on the second instar of Aedes aegypti mosquito larvae
Authors: Basu Baul Tushar S. , Dhar Sushmita , Rivarola Eleonora , Smith Frank E. , Butcher Ray , Song Xueqing , McCain Melodie , Eng George 
Published: April 2003

AbstractThe preparation and spectroscopic characterization of some complexes of the type Bu2Sn(LH)2 (LH = 5‐[(E)‐2‐(aryl)‐1‐diazenyl]‐2‐hydroxybenzoate) are reported. On the basis of spectroscopic evidence (1H, 13C, 119Sn NMR, IR and 119mSn Mössbauer) the compounds were judged to adopt the usual dicarboxylato structural type with a skew trapezoidal arrangement. This was further confirmed by X‐ray crystallography in the case of Bu2Sn(L5H)2 (L5H = 5‐[(E)‐2‐(4‐chlorophenyl)‐1‐diazenyl]‐2‐hydroxybenzoate). Toxicity studies of the di‐ and tri‐organotin compounds on the second larval instar of Aedes aegypti mosquito larvae are reported. Copyright © 2003 John Wiley & Sons, Ltd.
Crystallographic report: Crystal and molecular structure of tetramethylammoniumdiisothiocyanatotriphenyltin(IV), [NMe4SnPh3(NCS)2]
Authors: Okio Kochikpa Y. A. , Diop Libasse , Barry Aliou H. , Jouini Tahar , Ortega Simòn H. 
Published: April 2003

AbstractThe structure of NMe4SnPh3(NCS)2 is molecular, without any significant intermolecular contacts in the lattice. The trigonal plane around the tin atom is defined by three carbon atoms from the phenyl groups and the axial positions occupied by the NCS groups. Copyright © 2003 John Wiley & Sons, Ltd.
Crystallographic report: Crystal structure of tetra(4‐methyl‐5‐imidazole‐carboxyaldehyde)zinc(II) diperchlorate
Authors: Long La‐Sheng , Ren Yan‐Ping , Huang Rong‐Bin , Zheng Lan‐Sun 
Published: April 2003

AbstractThe central zinc(II) atom in the title complex is tetrahedrally coordinated by four nitrogen atoms derived from 4‐methyl‐5‐imidazolecarboxyaldehyde ligands with Zn N in the range 2.007(3) to 2.026(4) Å. Copyright © 2003 John Wiley & Sons, Ltd.
Pendant functional group copolyether sulfones: III. Modified copolyether sulfones with bisphenolic copper chelate
Authors: Cozan Vasile , Butuc Elena , Avram Ecaterina , Airinei Anton 
Published: April 2003

AbstractNew copolyether sulfones having copper(II) chelate units as pendant groups were synthesized by a chemical modification reaction of chloromethylated polysulfones with the sodium salt of copper(II) bis(2,4‐dihydroxybenzaldehyde) in dichloromethane/dimethyl sulfoxide as solvent system, at room temperature. The resulting copolymers were confirmed by IR absorption spectra and characterized by softening points, solubilities, differential scanning calorimetry and thermogravimetric analysis measurements. A slow increase of glass transition temperature values was observed in comparison with the starting chloromethylated polysulfones, and the thermal stability in air showed a slow, but insignificant, decrease. A significant increase in solvent resistance was observed. The glass transition temperature values, which do not exceed 200 °C, provide processing possibilities. Copyright © 2003 John Wiley & Sons, Ltd.
New organotin(IV) derivatives of dipeptides as models for metal–protein interactions: in vitro anti‐tumour activity
Authors: Nath Mala , Pokharia Sandeep , Song Xueqing , Eng George , Gielen Marcel , Kemmer Martine , Biesemans Monique , Willem Rudolph , de Vos Dick 
Published: April 2003

AbstractNew organotin(IV) derivatives with general formulae R2SnL, where R = n−Bu and L is the dianion of glycyltyrosine (H2L‐1), glycyltryptophane (H2L‐2), leucyltyrosine (H2L‐3), leucylleucine (H2L‐4), valylvaline (H2L‐5) and alanylvaline (H2L‐6) have been synthesized in 1 : 1 molar ratio by the reaction of Bu2SnO with the respective dipeptide under azeotropic removal of water. Triphenyltin glycylleucinate was obtained by reacting Ph3SnCl and sodium glycylleucinate with filtration of NaCl formed. The bonding and coordination behaviour in these derivatives are discussed on the basis of IR, multinuclear 1H, 13C and 117Sn magnetic resonance and 119Sn Mössbauer spectroscopic studies. These investigations suggest that all the ligands in R2SnL act as dianionic tridentates coordinating through the COO−, NH2 and Npeptide groups, whereas in Ph3Sn(HL) the ligand acts as a bidentate coordinating through the COO− and NH2 groups. The 119Sn Mössbauer studies, together with the NMR data, indicate that, for the 1 : 1 monomeric derivatives, the polyhedron around tin in R2SnL is a trigonal bipyramid with the butyl groups and Npeptide in the equatorial positions, while the axial positions are occupied by a carboxylic oxygen and the amino nitrogen atom. In Ph3Sn(HL) the structure is intermediate between pseudotetrahedral and cis‐trigonal bipyramidal, with the Namino and two phenyl groups in the equatorial plane and the carboxylate oxygen and the third phenyl group in axial positions. All the complexes have been screened against seven cancer cell lines of human origin, viz. MCF‐7, EVSA‐T, WiDr, IGROV, M19, MEL A498 and H226. Ph3Sn(HL) displays the lowest ID50 values of the tin compounds tested and reported in this paper. Its activity is comparable to those of methotrexate and 5‐fluorouracil. All the di‐n‐butyltin compounds exhibit lower in vitro anti‐tumour activities than Ph3Sn(HL); however, they do provide significantly better activities than etoposide and cis‐platin. Copyright © 2003 John Wiley & Sons, Ltd.
Kinetics of thermal decomposition of unsaturated polyester resins with reduced flammability
Authors: Kicko‐Walczak Ewa 
Published: April 2003

AbstractIn this article, the kinetics of thermal decomposition of unsaturated maleic–phthalic polyester resins, flame‐retarded with zinc hydroxystannate, was studied by thermogravimetric analysis at different heating rates. At the first stage, it was found, on the basis of isoconversional analysis by the methods of Friedman and of Ozawa–Flynn–Wall, that the value of the (apparent) activation energy (E) characteristically changes in three steps during the degradation. Further kinetic studies using nonlinear regression methods revealed the best fits for both pristine and stabilized resins. It was observed that the course of E versus the degree of conversion (α) during degradation of zinc hydroxystannate‐containing resins (α > 0.8) was characterized by higher values of E—this phenomenon can be explained in terms of the flame‐retardation action of zinc hydroxystannate, which is believed to operate primarily in the condensed phase. At the next stage, kinetic analysis by the nonregression method was performed to find the kinetic model [f(α) function] of the decomposition process; hence, for pristine resin, the best fit was found for the Avrami–Yerofeeyev model (nuclei growth), and for stabilized samples, the nth‐order function with catalysis proved to be the best approximation. The obtained kinetic parameters in the form of E, the preexponential factor A, and the model function f(α) allow a prediction of the polyester resin's thermal behavior in an extrapolated range of degree of conversion, time, and temperature. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2851–2857, 2003
Preparation of asymmetric PVA membranes using ternary system composed of polymer and cosolvent
Authors: Kim Sang‐Gyun , Kim Yong‐Il , Yun Hyung‐Gu , Lim Gyun‐Taek , Lee Kew‐Ho 
Published: April 2003

AbstractIntegrally skinned PVA membranes have been prepared from PVA/NMP/water system by the phase inversion method in 2‐propanol bath, and the pervaporation characteristics of these membranes were investigated. With an increase in the NMP content in the polymer solution, the formation of skin layer depended on the NMP content in the cosolvent, and the overall morphology of membranes changed from porous to dense structure. Particularly, PVA membranes showed an asymmetric structure composed of a dense skin layer and a porous sublayer with finger‐like type and cellular structure in solvents of 50–60% NMP compositions. The experimental results from the pervaporation separation of MTBE and methanol mixtures were also in good agreement with the morphology for the formation of skin layer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2884–2890, 2003
The effect of reaction time and temperature during heterogenous alkali deacetylation on degree of deacetylation and molecular weight of resulting chitosan
Authors: Tsaih Ming Larng , Chen Rong H. 
Published: April 2003

AbstractThe objective of the study is to elucidate the effect of reaction time and temperature during heterogenous alkali reaction on degree of deacetylation (DD) and molecular weight (MW) of the resulting chitosans, and to establish the reaction conditions to obtain desired DD and MW chitosan products. Chitin was extracted from red shrimp process waste. DDs and MWs were determined by infrared spectroscopy (IR) and static light scattering, respectively. The results are as follow: The DD and MW of chitin obtained were 31.9% and 5637 kDa, respectively. The DD of the resulting chitosan increased along with reaction time and/or reaction temperature. The DDs of the resulting chitosan that were obtained from 140°C were higher than those reacted at 99°C. The highest DD of the resulting chitosans after alkali deacetylation at 99 and 140°C were 92.2 and 95.1%, respectively. The DDs of chitosans increased fast at the beginning of reaction process then slowed over time. The reaction rate and rate constant of the deacetylation reaction decreased with increasing DD of the reactant. The MWs of chitosans decreased along with the deacetylation time. MW of those chitosans reacted at 140°C are smaller than those at 99°C. The rate of chitosan degradation was above 43.6%/h in the initial stage, then decreased to about 20%/h. The degradation rate constants raised substantially in the late stage. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2917–2923, 2003
Dynamic mechanical properties of styrene‐butadiene rubber vulcanizate filled with electron beam modified surface‐treated dual‐phase filler
Authors: Shanmugharaj A. M. , Bhowmick Anil K. 
Published: April 2003

AbstractThe influence of the electron beam modification of a dual‐phase filler on the dynamic mechanical properties of styrene‐butadiene rubber (SBR) is investigated in the presence and absence of trimethylol propane triacrylate or triethoxysilylpropyltetrasulfide. Electron beam modification of the filler results in reduction of the tan δ at 70°C, a parameter for rolling resistance, and an increase in the tan δ at 0°C, a parameter for wet skid resistance of SBR vulcanizates. These modified fillers give significantly better overall performance in comparison with the control dual‐phase filler. This variation in properties is explained in terms of filler parameters such as the filler structure that leads to rubber occlusion and filler networking. These results are further corroborated using the master curves obtained by the time–temperature superposition principle. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2992–3004, 2003
Dielectric properties and morphology of polymer composites filled with dispersed iron
Authors: Zois Haralampos , Apekis Lazaros , Mamunya Yevgen P. 
Published: April 2003

AbstractThe dielectric properties and the structure of various metal–polymer composites, based on a polymer matrix of polyamide (PA), polyethylene (PE), polyoxymethylene (POM), or blend PE/POM filled with dispersed iron (Fe) particles, have been investigated in this work. In PE–Fe, PA–Fe, and POM–Fe composites the filler spatial distribution is random. In the PE/POM–Fe composites, the polymer matrix is two‐phase and the filler particles are localized only in the POM phase, resulting in an ordered distribution of the dispersed filler particles within the blend. The concentration and frequency dependence of the dielectric permittivity, ε′, and the dielectric loss tangent, tanδ, are described in terms of the percolation theory. The experimental values of the critical exponents (namely, s, r, and y) are in good agreement with those predicted by the theory for the composites with random filler distribution. The PE/POM–Fe composites demonstrate low value of the percolation threshold, PC, and high values of the critical exponents r and y. This is attributed to the specific structure of these composites. A schematic model for the morphology of the composites studied has been proposed. This model explains the peculiar behavior of the PE/POM–Fe composites by assuming ordered distribution of the filler particles in a binary polymer matrix. The proposed model is in good agreement with the results of optical microscopy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3013–3020, 2003
Network characterization and swelling behavior of chemical hydrogels based on acid‐containing poly(vinyl alcohol)
Authors: Ruiz J. , Mantecón A. , Cádiz V. 
Published: April 2003

AbstractPoly(vinyl alcohol) (PVA) was modified with phthalic and succinic anhydrides to give vinyl alcohol–vinyl ester copolymers that contain carboxylate groups. These half‐esters were then crosslinked by using the poly‐ (ethylene glycol) (PEG) 400 diglycidylether. Low crosslinker/carboxylate ratios were used to obtain low degrees of crosslinking, so the capacity of the resulting hydrogel to absorb water was high. Water absorption was determined gravimetrically as a function of time at room temperature. The equilibrium swelling ratio and compressive modulus were characterized for all the resulting PVA hydrogels and related to the network structure. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3026–3031, 2003
Age and sex differences in hip joint space among asymptomatic subjects without structural change: Implications for epidemiologic studies
Authors: Lanyon Peter , Muir Kenneth , Doherty Sally , Doherty Michael 
Published: April 2003

AbstractObjectiveThe prevalence of hip osteoarthritis (OA) increases significantly with age. Although it is not clear whether joint space loss at the hip is a feature of normal aging or a reflection of the OA process, epidemiologic criteria for OA are based on narrowing alone. The aim of this study was to determine whether changes in joint space width occur with age, and whether there are sex differences, in asymptomatic subjects without hip OA.MethodsWe identified a total of 1,806 subjects who had undergone intravenous urography between 1994 and 1996 and sent a questionnaire to the 1,527 of these subjects who were alive in 1998; 1,031 replies (68%) were received. All radiographs were read by an observer blinded to age, sex, and pain status. Individual radiographic features of OA (narrowing, osteophyte, sclerosis, and cysts) were graded, and an overall qualitative grade was allocated, according to a standard atlas. Minimum joint space width (JSW) was measured by metered caliper to within 0.1 mm. A total of 276 women (mean age 63 years) and 257 men (mean age 64 years) were identified who had never had hip pain (defined as having ever had pain on most days for at least 1 month) and who had no evidence of either joint space narrowing or osteophyte (grade 0, no structural changes). The minimum JSW in either hip was tabulated according to age.ResultsJSW measurement was reproducible (95% confidence limits of agreement) to within ±0.5 mm. At all ages, men had larger JSW than women (3.85 mm in women, 4.19 mm in men, mean difference 0.34 mm; 95% confidence interval [95% CI] 0.24, 0.44). A significant decline in JSW with age was seen in women, with a mean difference between ages 45–54 and 75–84 years of 0.36 mm (95% CI 0.15, 0.58; P = 0.001). No significant change in JSW with age was seen in men (mean difference 0.16 mm; 95% CI −0.11, 0.43). Analysis of an additional 64 women and 61 men who were without hip pain and had overall qualitative grade 1–2 changes gave similar results. Implementing these results to alter the threshold for definition of hip OA in women from ≤2.5 mm to ≤2.2 mm reduced the prevalence of hip OA from 10.6% to 5.6%.ConclusionThese sex differences in joint space have significant implications in terms of the major emphasis on joint space narrowing in definitions of hip OA. Women also have a significant progressive decline in joint space with age that is not seen in men. This suggests that in women, loss of cartilage may be an age‐related phenomenon that is independent of other aspects of structural change. Consideration should be given to the development of sex‐specific definitions of hip “OA.”