bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chlorocarbons and Chlorohydrocarbons, Toxic Aromatics
Authors: Safe Stephen H. 
Published: August 2004

AbstractPolychlorinated biphenyls (PCBs) and naphthalenes (PCNs) are halogenated aromatic industrial compounds produced and marketed for a wide variety of applications. PCBs were used as heat‐transfer fluids, organic diluents, lubricant inks, plasticizers, fire retardants, paint additives, sealing liquids, immersion oils, adhesives, dedusting agents, waxes, and as dielectric fluids for capacitors and transformers. PCNs were used as waxes and impregnants (for protective coatings), water repellents, and wood preservatives. PCBs have been identified as contaminants in almost every component of the global ecosystem including the air, water, sediments, fish, wildlife, and humans. PCNs are only infrequently detected because these products had been used much less than the commercial PCBs. The toxicology of PCBs has been extensively studied and the commercial mixtures elicit a broad spectrum of toxic and biochemical responses.γ‐Lindane is a chlorinated hydrocarbon pesticide that has also been widely identified in the environment. The toxic responses elicited by γ‐lindane in laboratory animals include hepato‐ and nephrotoxicity, reproductive and embryotoxicity, mutagenicity in some short termin vitrobioassays, and carcinogenicity. Only minimal data are available on the mammalian toxicities of hexachlorocyclopentadiene. The impact of environmental exposure to γ‐lindane is unknown and only minimal toxic effects have been observed in occupationally‐exposed individuals.
Fibers, Vegetable
Authors: Young Raymond A. 
Published: August 2004

Abstract
Plant‐derived vegetable fibers are classified according to their source in plants as bast, leaf, or seed‐hair. The fibers in bast and leaf plants are integral to the plant structure, providing strength and support. The principal chemical component of vegetable fibers is cellulose, with varying amounts of lignin and hemicelluloses also usually present; thus the fibers are also referred to as cellulosic or lignocellulosic. Vegetable fibers are usually stiffer but less tough than synthetic fibers. The fibers are grown throughout the world but mostly in tropical and subtropical climates in developing countries. The principal bast fibers are flax, jute, and hemp which are utilized primarily for fabrics (linen‐flax, hessian‐jute), bags, ropes, and as a source of papermaking fibers, principally cigarette papers. The primary leaf fibers are abaca and sisal, which have uses similar to bast fibers, except fabrics are not produced from the leaf fibers. Cotton, coir, and kapok are the principal seed‐hair fibers, with cotton by far the most important commercial vegetable fiber. Bast fibers are obtained from the plant, after harvest, by water retting (rotting) in ponds or streams. The leaf fibers are obtained by crushing and scraping followed by washing. Vegetable fibers are generally graded according to color, luster, cleanliness, strength, fineness, and uniformity. The world market for vegetable fibers has dropped over 30% in recent years because periods of economic recession and synthetic fiber replacements.
Modifying irregular titania powders in a low power microwave plasma torch
Authors: Vanamu Ganesh , Lester Kelvin , Datye Abhaya K. , Weigle John C. , Chen Chun‐Ku , Kelly Daniel , Phillips Jonathan 
Published: August 2004

AbstractRapid passage of titania powder as an aerosol through a plasma generated with a low power microwave torch, resulted in many changes to the powder. Some or all of the titania became spherical, its phase changed, the level of carbon impurity changed, and its surface area declined. The final state of the titania depended on plasma operating conditions. For example, all of the titania became spherical and converted to the rutile phase, only if the processing rate remained low. Complete spherodization occurred only if the energy absorbed by the particles was <2.5% of the total power applied. Excess solid loading reduced the fraction spherodized or otherwise modified, as well as the net rate of conversion. Passing titania through an oxygen plasma removed virtually all the carbon impurity. This process is similar to alumina studies in the same apparatus and suggests that many refractory oxides can be modified by low‐power plasmas. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2090–2100, 2004
Body fatness and clustering of cardiovascular disease risk factors in Portuguese children and adolescents
Authors: Ribeiro José Carlos , Guerra Sandra , Oliveira José , Andersen Lars Bo , Duarte José Alberto , Mota Jorge 
Published: August 2004

AbstractModifiable cardiovascular risk factors that increase the risk for cardiovascular diseases (CVD) in adult populations have also been observed in pediatric populations. Childhood and adolescence obesity has been strongly implicated in the clustering of risk factors. The aims of the present study were 1) to examine whether clustering of CVD risk factors, either biological risk factors (high blood pressure (HBP), percentage of high fat mass (%HBF), and high total cholesterol (HTC)) and one behavioral/lifestyle risk factor (low physical activity index (LPAI)) exist, and 2) to analyze the relationship between body fatness and the clustering of other risk factors. The cluster of CVD risk factors was determined in 1,533 (8–15 years of age) children, 731 males (age 10.8 ± 2.3 years; weight, 40.6 ± 12.7 kg; height, 143.1 ± 14.1 cm; BMI, 19.4 ± 3.4 kg−2) and 802 females (age, 11.0 ± 2.4; weight, 41.0 ± 12.4; height, 142.8 ± 13.2; BMI, 19.7 ± 3.5). Sex‐ and age‐specific “high risk” quartiles were formed for each of the biological risk factors and the lifestyle factor. Thus, for blood pressure (high blood pressure, HBP), cholesterol (high cholesterol, HTC), and obesity (high percent of body fat, HBF), the sex‐ and age‐adjusted 4th quartile (4Q) was defined as the “high risk” quartile, while for physical activity the 1st quartile (1Q) was defined as the “high risk” quartile. The majority of children (62% of boys and 62% of girls) at risk of obesity are at risk of another risk factor. In our sample, estimated ORs indicated that, compared with 1Q, the “risk of obesity” children and adolescents were two times as likely (P < 0.001) to have two or three risk factors. Our results suggest that children 8–15 years old in the highest quartile of body fatness are an increased risk of having a cluster of other risk factors, namely HBP, HTC, and LPAI. These data provide further evidence that juvenile obesity warrants early intervention because the patterns of unhealthy behavior are formed in adolescence and young adulthood. Am. J. Hum. Biol. 16:556–562, 2004. © 2004 Wiley‐Liss, Inc.
Peak oxygen uptake in relation to age, sex, and maturation in Hong Kong Chinese children
Authors: McManus Alison M. , Chung Yung Tak , Leung Maurice P. 
Published: August 2004

AbstractThis cross‐sectional study was designed to provide baseline information on peak oxygen uptake for Southern Chinese children in relation to age and sexual maturation. Sixty‐three boys and 84 girls, classified for stage of sexual maturation using Tanner's stages, successfully completed a peak oxygen uptake test. ANOVA was used to examine differences in absolute and mass‐related peak VO2. The least‐squares log‐linear relationship between mass and peak VO2 was examined using analysis of covariance. We found no difference between boys' and girls' peak VO2 prior to puberty. Absolute peak VO2 values for under‐10‐year‐old Chinese girls and boys were 17% and 19%, respectively, lower than Caucasian predicted values. Log‐linear adjusted means for prepubertal boys and girls were 34% and 33% lower than Caucasian boys and girls, respectively. By adolescence, values were comparable to Caucasian values. South Chinese children show a distinct pattern of development relative to Caucasian children, particularly in the younger age groups. Am. J. Hum. Biol. 16:602–605, 2004. © 2004 Wiley‐Liss, Inc.
Energetic factors and seasonal changes in ovarian function in women from rural Poland
Authors: Jasienska Grazyna , Ellison Peter T. 
Published: August 2004

AbstractFemale mammals can optimize their fitness by temporal suppression of reproductive function in response to unfavorable environmental conditions. Since reproduction is energetically demanding for a human female, ovarian function is expected to be sensitive to factors influencing energy availability and metabolism. Dieting and exercise in women from industrial countries, and low‐calorie diet and workload in women from developing countries, are often associated with ovarian suppression. This study shows that in Polish rural women seasonal changes in workload correlate with seasonal changes in indices of ovarian function (progesterone measured in saliva samples collected daily for six menstrual cycles for each subject). Mean levels of energy expenditure of the most work demanding weeks of the summer exceeded mean levels of energy expenditure during winter by 37%. Energy intake in this population was sufficient throughout the year. During the summer, when physical work was most intense, low values of progesterone levels were observed (178.2 pmol/L in July and 182.2 pmol/L in August), indicating ovarian suppression. Mean progesterone levels rose to 234.6 pmol/L in October when levels of energy expenditure were lower due to cessation of harvest‐related activities. As indicated by several causal models tested through path analysis, energy expenditure was the only variable responsible for suppressed progesterone levels during the summer. Variables describing the nutritional status and energy balance did not correlate significantly with progesterone levels; neither body weight nor body fat or seasonal changes of these variables seem to influence ovarian function in this population. Thus work‐related energy expenditure does not need to lead to negative energy balance in order to cause suppression of reproductive function in women. Am. J. Hum. Biol. 16:563–580, 2004. © 2004 Wiley‐Liss, Inc.
Ecogeographic size variations in sifakas: A test of the resource seasonality and resource quality hypotheses
Authors: Lehman Shawn M. , Mayor Mireya , Wright Patricia C. 
Published: August 2004

AbstractEcogeographic size variations have been documented in some but not all sifakas. Few morphometric or body weight data have been available for two critically endangered subspecies of diademed sifakas: Perrier's sifakas (Propithecus diadema perrieri) and silky sifakas (Propithecus diadema candidus). The objectives of our study were to determine size variations in sifakas and if these variations are related to resource quality and/or resource seasonality. P. d. perrieri and P. d. candidus were captured, weighed, and measured in northern Madagascar. Body weights and morphometrics were compared with other subspecies of diademed sifakas and indris (Indri indri). Differences in body weights and morphometrics between taxa are particularly pronounced for P. d. perrieri compared to P. d. diadema, P. d. edwardsi, and I. indri. Most morphometrics varied in comparisons between P. d. candidus and the other Indriidae (P. d. diadema, P. d. edwardsi, and I. indri). Average body size in sifakas is positively correlated with annual rainfall and negatively correlated with length of dry season. Sifaka body size is not correlated with protein‐to‐fiber ratios. Thus, size variations in sifakas are related to resource seasonality rather than resource quality. The relationships between the temporal availability of food resources and sifaka body size reflect complex and regionally varying causalities. Detailed, longitudinal information on the ecological factors underlying food selection and nutrient requirements in sifakas are needed to determine the relationship between ecogeographic variables and body size in sifakas. Am J Phys Anthropol, 2004. © 2004 Wiley‐Liss, Inc.
Glucose hypometabolism of hypothalamus and thalamus in narcolepsy
Authors: Joo Eun Yeon , Tae Woo Suk , Kim Jee Hyun , Kim Byung Tae , Hong Seung Bong 
Published: August 2004

AbstractIt has been hypothesized that hypothalamus is involved in narcolepsy. The relative difference between cerebral glucose metabolism of 24 narcoleptic patients and 24 normal controls was studied using 18F‐fluorodeoxy glucose positron emission tomography. Patients with narcolepsy showed significantly reduced cerebral glucose metabolism in bilateral rectal and subcallosal gyri, the medial convexity of right superior frontal gyrus, bilateral precuneus, right inferior parietal lobule, and in left supramarginal gyrus (uncorrected p < 0.001). Bilateral posterior hypothalami and mediodorsal thalamic nuclei showed hypometabolism with significance at the level of corrected p < 0.05, with small volume correction. This study showed cerebral glucose hypometabolism of the hypothalamus‐thalamus‐orbitofrontal pathways in the narcoleptic brain. Ann Neurol 2004
Crystallographic report: A synthetic precursor for hetero‐binuclear metal complexes, [Ru(bpy)(dppy)2(CO)2](PF6)2 (bpy = 2,2′‐bipyridine, dppy = 2‐(diphenylphosphino)pyridine)
Authors: Ooyama Dai , Sato Masahito 
Published: August 2004

AbstractIn the title complex, [Ru(bpy)(dppy)2(CO)2](PF6)2 (bpy = 2,2′‐bipyridine, dppy = 2‐(diphenylphosphino)pyridine), the ruthenium atom exhibits a slightly distorted octahedral coordination with the carbonyl ligands in cis positions. In addition, two dppy ligands coordinate to the ruthenium center through the phosphorus atoms in mutually trans positions and two pyridyl nitrogen atoms of the dppy direct toward two carbonyl ligands. Copyright © 2004 John Wiley & Sons, Ltd.
Crystallographic report: Crystal and molecular structure of triphenyltin thiazole‐2‐carboxylate
Authors: Yin Han‐Dong , Wang Chuan‐Hua 
Published: August 2004

AbstractThe tin atom in the title compound is in a distorted C3O tetrahedral geometry, as the carboxylate ligand is effectively monodentate. Copyright © 2004 John Wiley & Sons, Ltd.
Crystallographic report: catena‐Poly[aqua(phenyl‐1,3‐bisoxyacetato) tris(pyridine)cadmium(II)], [(H2O)(C5H5N)3 (O2CCH2OC6H4OCH2CO2)Cd]n
Authors: Gao Shan , Liu Ji‐Wei , Ng Seik Weng 
Published: August 2004

AbstractThe [O2CCH2OC6H4OCH2CO2]2− group bridges adjacent planar [(H2O)(C5H5N)3Cd]2+ units into a linear chain. The carboxyl groups occupy opposite sites in the octahedral environment of the cadmium atom. Copyright © 2004 John Wiley & Sons, Ltd.
Simulation and optimization of the continuous tower process for styrene polymerization
Authors: Bhat Shrikant A. , Sharma Rahul , Gupta Santosh K. 
Published: August 2004

AbstractThe continuous tower process, a popular industrial process for the manufacture of polystyrene, was simulated and optimized. A kinetic model for the thermal polymerization of styrene, which takes into account the Trommsdorff effect and the volume change accompanying the reaction, was developed. This was used to formulate model equations for the continuous flow stirred tank reactor (CSTR) and plug flow reactor (several sections) in the tower process. The model can predict monomer conversion, number‐ and weight‐average molecular weights, polydispersity index (PDI), and temperature at various locations in the unit, under specified operating conditions. Multiobjective optimization of this process was also carried out, for which an adaptation of a genetic algorithm (GA) was used. The two objectives were maximization of the final monomer conversion and minimization of the PDI of the product. The conversion in the CSTR was constrained to lie within a desired range, and polymer having a specified value of the number‐average molecular weight was to be produced. The optimal solution was a unique point (no Pareto sets were obtained). The optimal solutions indicated that the tower process is operated under near‐optimal conditions. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 775–788, 2004
Synthesis and characterization of novel polyesterimides
Authors: Shieh Jeng‐Yueh , Hsu Pei‐Hsuan , Wang Chun‐Shan 
Published: August 2004

AbstractA series of soluble novel polyesterimides was synthesized from diamines [a mixture of 2,2‐bis(4‐(4‐aminophenoxy)phenyl)propane (BAPP) with amine‐terminated polysiloxane (ATPS) in various mole ratios] and the ester‐group‐containing dianhydrides. The ester group containing dianhydrides in turn was synthesized by the transesterification reaction of trimellitic anhydride (TMA) with diacetate ester of hydroquinone (HQ), 4,4′‐dihydrophenyl (BP), 1,6‐hexanediol, or ethylene glycol. The resulted polyesterimides were characterized by using Fourier‐transform infrared spectroscopy, inherent viscosity, solubility, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The polyesterimides of BP and HQ had relatively high glass transition temperatures in the range of 214.7–227.2 and 195.7–210.5°C, respectively. The glass transitions decreased rather slowly with the increase in polysiloxane content. Thermal stability and the weight‐loss behavior of polyesterimides were studied by TGA. All polyesterimides of BP and HQ (BPI and HQI) showed no significant weight loss below 500°C in a N2 environment, and the decomposition temperatures (Td5%) of BPI and HQI were >520°C. Most polyesterimides were soluble in polar aprotic solvents and m‐cresol. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 730–738, 2004
Toward a basic framework for webometrics
Authors: Björneborn Lennart , Ingwersen Peter 
Published: August 2004

AbstractIn this article, we define webometrics within the framework of informetric studies and bibliometrics, as belonging to library and information science, and as associated with cybermetrics as a generic subfield. We develop a consistent and detailed link typology and terminology and make explicit the distinction among different Web node levels when using the proposed conceptual framework. As a consequence, we propose a novel diagram notation to fully appreciate and investigate link structures between Web nodes in webometric analyses. We warn against taking the analogy between citation analyses and link analyses too far.
Formally citing the Web
Authors: Wouters Paul , Vries Repke de 
Published: August 2004

AbstractHow do authors refer to Web‐based information sources in their formal scientific publications? It is not yet well known how scientists and scholars actually include new types of information sources, available through the new media, in their published work. This article reports on a comparative study of the lists of references in 38 scientific journals in five different scientific and social scientific fields. The fields are sociology, library and information science, biochemistry and biotechnology, neuroscience, and the mathematics of computing. As is well known, references, citations, and hyperlinks play different roles in academic publishing and communication. Our study focuses on hyperlinks as attributes of references in formal scholarly publications. The study developed and applied a method to analyze the differential roles of publishing media in the analysis of scientific and scholarly literature references. The present secondary databases that include reference and citation data (the Web of Science) cannot be used for this type of research. By the automated processing and analysis of the full text of scientific and scholarly articles, we were able to extract the references and hyperlinks contained in these references in relation to other features of the scientific and scholarly literature. Our findings show that hyperlinking references are indeed, as expected, abundantly present in the formal literature. They also tend to cite more recent literature than the average reference. The large majority of the references are to Web instances of traditional scientific journals. Other types of Web‐based information sources are less well represented in the lists of references, except in the case of pure e‐journals. We conclude that this can be explained by taking the role of the publisher into account. Indeed, it seems that the shift from print‐based to electronic publishing has created new roles for the publisher. By shaping the way scientific references are hyperlinking to other information sources, the publisher may have a large impact on the availability of scientific and scholarly information.
Transposition of the cocitation method with a view to classifying Web pages
Authors: Prime‐Claverie Camille , Beigbeder Michael , Lafouge Thierry 
Published: August 2004

AbstractThe Web is a huge source of information, and one of the main problems facing users is finding documents which correspond to their requirements. Apart from the problem of thematic relevance, the documents retrieved by search engines do not always meet the users' expectations. The document may be too general, or conversely too specialized, or of a different type from what the user is looking for, and so forth. We think that adding metadata to pages can considerably improve the process of searching for information on the Web. This article presents a possible typology for Web sites and pages, as well as a method for propagating metadata values, based on the study of the Web graph and more specifically the method of cocitation in this graph.
Understanding the Nature of the Molecular Mechanisms Associated with the Competitive Lewis Acid Catalyzed [4+2] and [4+3] Cycloadditions between Arylidenoxazolone Systems and Cyclopentadiene: A DFT Analysis
Authors: Arnó Manuel , Picher M. Teresa , Domingo Luis R. , Andrés Juan 
Published: August 2004

AbstractThe molecular mechanisms of the reactions between aryliden‐5(4H)‐oxazolone 1, and cyclopentadiene (Cp), in presence of Lewis acid (LA) catalyst to obtain the corresponding [4+2] and [4+3] cycloadducts are examined through density functional theory (DFT) calculations at the B3LYP/6‐31G* level. The activation effect of LA catalyst can be reached by two ways, that is, interaction of LA either with carbonyl or carboxyl oxygen atoms of 1 to render [4+2] or [4+3] cycloadducts. The endo and exo [4+2] cycloadducts are formed through a highly asynchronous concerted mechanism associated to a Michael‐type addition of Cp to the β‐conjugated position of α,β‐unsaturated carbonyl framework of 1. Coordination of LA catalyst to the carboxyl oxygen yields a highly functionalized compound, 3, through a domino reaction. For this process, the first reaction is a stepwise [4+3] cycloaddition which is initiated by a Friedel–Crafts‐type addition of the electrophilically activated carbonyl group of 1 to Cp and subsequent cyclization of the corresponding zwitterionic intermediate to yield the corresponding [4+3] cycloadduct. The next rearrangement is the nucleophilic trapping of this cycloadduct by a second molecule of Cp to yield the final adduct 3. A new reaction pathway for the [4+3] cycloadditions emerges from the present study.