bluuebunny/crossref_metadata_2025_split huggingface dataset:
Farming and the prevalence of non‐reversible airways obstruction—results from a population‐based study
Authors: Lamprecht B. , Schirnhofer L. , Kaiser B. , Studnicka M. , Buist A.S. 
Published: May 2007

AbstractIntroductionOccupational exposure to noxious dusts, gases, and fumes most likely contributes to obstructive lung disease. We studied whether self‐reported farming work is associated with non‐reversible airways obstruction.MethodsFollowing the burden of obstructive lung disease (BOLD) study protocol, we surveyed a gender‐stratified population‐based sample of 2,200 adults aged 40 years and over. Pre‐ and post‐bronchodilator spirometry, as well as information on smoking, occupation, and reported respiratory disease was recorded. According to GOLD criteria, non‐reversible airways obstruction was defined as a post‐bronchodilator forced expiratory volume (FEV1)/forced vital capacity (FVC) < 0.70. Occupational and smoking history was based on questionnaire. Farming was defined as ever working in this occupation for 3 months or longer.ResultsFor 1,258 participants with complete data (post‐bronchodilator spirometry and questionnaire data), 288 (=22.9%) reported farming. Among the 288 participants reporting farming, the prevalence of non‐reversible airways obstruction was 30.2%. Farming was significantly associated with airways obstruction: chronic obstructive pulmonary disease (COPD) GOLD stage I or higher (OR 1.5; 95% CI 1.1–2.0) and COPD GOLD stage II or higher (OR 1.8; 95% CI 1.2–2.7). The latter estimate was unchanged when adjustment for competing risks gender, age, and smoking was done. In this population the risk for non‐reversible airways obstruction attributable to farming was 7.7%.ConclusionFarming should be considered a risk factor for non‐reversible airways obstruction. Am. J. Ind. Med. 50:421–426, 2007. © 2007 Wiley‐Liss, Inc.
Behavioral phenotype of sex chromosome aneuploidies: 48,XXYY, 48,XXXY, and 49,XXXXY
Authors: Visootsak Jeannie , Rosner Beth , Dykens Elisabeth , Tartaglia Nicole , Graham John M. 
Published: May 2007

AbstractSex chromosomal aneuploidy is the most common disorder of sex chromosomes in humans, with an incidence of 1 in 400 newborns. The addition of more than one extra X and/or Y chromosome to a normal male karyotype is less frequent and has its own distinctive physical and behavioral profile. This study examines the behavioral similarities and differences in individuals with 48,XXYY compared to 48,XXXY and 49,XXXXY. The participants include 11 males with 48,XXYY and 13 males with 48,XXXY and 49,XXXXY. Using the Vineland Adaptive Behavior, the Achenbach Child Behavior Checklist, and the Reiss Personality Profiles, parents are asked to characterize the behavior and personality of their boys with sex chromosome tetrasomy and pentasomy. Males with 48,XXYY have higher overall adaptive scales in daily living skills, socialization, and communication compared to males with 48,XXXY and 49,XXXXY. Both groups are at risk for maladaptive behavior, although 48,XXYY males are at a higher risk for internalizing and externalizing symptoms. 48,XXXY and 49,XXXXY function at a lower cognitive level and their behavior is often immature for their chronological age. Both groups display interests in helping others, but have a low tolerance for being rejected or teased. Specific recommendations and interventional strategies are provided for individuals with 48,XXYY, 48,XXXY, and 49,XXXXY. © 2007 Wiley‐Liss, Inc.
Effect of molecular structure of hybrid precursors on the performances of novel hybrid zwitterionic membranes
Authors: Liu Junsheng , Xu Tongwen , Fan Guangneng , Fu Yanxun 
Published: May 2007

AbstractThree types of novel hybrid zwitterionic membranes were prepared via a coupling reaction between two silane‐coupling agents in a nonaqueous system and a subsequent reaction with 1,4‐butyrolactone to create ion pairs in the hybrid precursors. FT‐IR spectra corroborated the corresponding reactions. The synthesized membranes were characterized by thermal analyses, ion‐exchange capacities, streaming potentials, and pure water flux. Thermal analyses exhibited that the degradation temperature of the hybrid precursors decreased with an increase in zwitterionic extent because of the introduction of ion pairs. Ion‐exchange capacity measurements revealed that the anion‐exchange capacities and cation‐exchange capacities were in the range of 0.023–0.05 and 0.32–0.58 mmol g−1, respectively. Streaming potentials displayed that when the membranes coated for one or three times, the isoelectric points were in the pH range of 6.6–7.58 and 6.58–7.7, respectively. The pure water flux showed that it could be affected by the coating times and the ingredients of these zwitterionic membranes. This difference in membrane's characteristics can be ascribed to the effect of molecular structure of the hybrid precursors. Both the Coulombic interactions of ion pairs between the polymer chains and the hydrophilicity of these membranes were proposed to clarify the above phenomena. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Effect of layering pattern on the water absorption behavior of banana glass hybrid composites
Authors: Pothan L. A. , Cherian B. M. , Anandakutty B. , Thomas Sabu 
Published: May 2007

AbstractHybridization of Banana fibers with glass fibers has been found to reduce the water absorption behavior of the composites in an earlier work by us. Banana fibers were hybridized with glass and different layering patterns were followed in the preparation of the composites. The effect of the various layering patterns on the water absorption of the composites was studied. It was found that water diffusion occurs in the composite depending on the layering pattern as well as the temperature. In all the experiments, it has been found that composites with an intimate mixture of glass and banana show the maximum water uptake except for temperature of 90°C. At 90°C the maximum water uptake is found to be for composites where there is one layer of banana and another layer of glass. The water uptake follows the same trend as that in all other temperatures till a time span of 4900 min is reached. The kinetics of diffusion was found to be Fickian in nature. The various thermodynamic parameters like sorption coefficient, diffusion coefficient. Enthalpy change, entropy change, and activation energy of the various composites were calculated. From all the calculations it has been concluded that layering pattern is an important parameter which controls the water absorption of the composites. The layering pattern Cg‐b‐g was found to have the lowest water uptake. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Optimal operation of ethylene polymerization reactors for tailored molecular weight distribution
Authors: Asteasuain M. , Brandolin A. 
Published: May 2007

AbstractThis work presents a comprehensive steady‐state model of the high‐pressure ethylene polymerization in a tubular reactor able to calculate the complete molecular weight distribution (MWD). For this purpose, the probability generating function technique is employed. The model is included in an optimization framework, which is used to determine optimal reactor designs and operating conditions for producing a polymer with tailored MWD. Two application examples are presented. The first one involves maximization of conversion to obtain a given MWD, typical of industrial operation. Excellent agreement between the resulting MWD and the target one is achieved with a conversion about 5% higher than the ones commonly reported for this type of reactor. The second example consists in finding the design and operating conditions necessary to produce a polymer with a bimodal MWD. The optimal design for this case involves a split of the initiator, monomer, and modifier feeds between the main stream and two lateral injections. To the best of our knowledge, this is the first work dealing with the optimization of this process in which a tailored shape for the MWD is included. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Synthesis, characterization, and swelling behavior of alginate‐g‐poly(sodium acrylate)/kaolin superabsorbent hydrogel composites
Authors: Pourjavadi Ali , Ghasemzadeh Hossein , Soleyman Rouhollah 
Published: May 2007

AbstractA novel superabsorbent composite based on sodium alginate and the inorganic clay kaolin was synthesized via the graft copolymerization of acrylic acid (AA) in an aqueous medium with methylene bisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. The effects of reaction variables, such as the MBA, AA, and APS concentrations and the alginate/kaolin weight ratio, on the water absorbency of the composite were systematically optimized. Evidence of grafting and kaolin interactions was obtained by a comparison of the Fourier transform infrared spectra of the initial substrates with that of the superabsorbent composite, and the hydrogel structure was confirmed with scanning electron microscopy. The results indicated that with an increasing alginate/kaolin weight ratio, the swelling capacity and gel content increased. The effects of various salt media were also studied, along with the swelling kinetics. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Preparation of self‐standing polyaniline‐based membranes: Doping effect on the selective ion separation and reverse osmosis properties
Authors: Deligöz Hüseyin 
Published: May 2007

AbstractThe selective ion transport of aqueous salt solutions including mono‐, di‐, trivalent cations across both doped and undoped polyaniline (PAni) membranes was described. PAni‐based asymmetric membranes were prepared by the phase inversion method from the casting solution containing N‐methyl pyrrolidone. It was found that the permeation rates (PR) decline in the sequence of PR(NaCl) > PR(MgCl2) > PR(LaCl3). HCl‐doped PAni membrane exhibited higher permeation rates for the salts than undoped one due to its more hydrophilic nature. In reverse osmosis (RO) applications, it was observed no water permeation through undoped PAni due to less permeable and hydrophobic nature, under even at 40 bar pressure. Concerning HCl‐doped PAni, this membrane showed very low water flux (Jw) and it was found as 1.01 L m−2 h−1 under 40 bar pressure. On the other hand, the J increased linearly with the applied pressure. Furthermore, typical separation factor (α)values calculated from permeation rate ratios were found to be as 6.3 and 39 for Na+/Mg2+ and Na+/La3+ for HCl‐doped PAni, respectively. Especially, HCl‐doped PAni membrane can be used for removing rare‐earth metal salts due to its high separation efficiency in high temperature applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Liquid‐crystalline behavior of chitosan in malic acid
Authors: Chang Jenq Sheng , Chang Ke Liang B. , Tsai Min Lang 
Published: May 2007

AbstractThis report describes how the degree of deacetylation and molecular weight of chitosan and the concentrations of sodium chloride and malic acid affect the formation of lyotropic chitosan liquid crystals. Chitosan samples of various degrees of deacetylation were prepared from β‐chitin that was isolated from squid pens. They were degraded by ultrasonic irradiation to various molecular weights. The critical concentrations forming chitosan liquid crystals were determined with a polarized microscope. A chitosan sample with a degree of deacetylation of 67.2–83.6% formed cholesteric lyotropic liquid crystals when it was dissolved in 0.37–2.59M malic acid. The critical concentrations increased with increasing degrees of deacetylation of chitosan. They decreased with increasing molecular weights or increasing concentrations of sodium chloride and malic acid. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Radiation‐induced oxygen scavenging activity in EVOH copolymers
Authors: López‐Rubio Amparo , Lagarón José María , Yamamoto Tomoyuki , Gavara Rafael 
Published: May 2007

AbstractOxygen scavenging capacity has been observed for the first time in an ethylene‐vinyl alcohol (EVOH29, i.e., 29 mol % of ethylene) copolymer as a consequence of electron beam irradiation at doses of 30 and 90 kGy. This oxygen blocking activity is thought to arise from the reaction of oxygen with the free radicals formed during the irradiation process and it has been observed to be dependent of the irradiation dose, i.e., the higher the dose, the longer the time the polymer is able to react with oxygen. The characterization of the irradiated polymeric samples has been carried out through DSC and FT‐IR and the oxygen transmission rate has been measured as a function of time and compared with the properties of the nonirradiated material. A drop in the melting point and in the enthalpy of fusion and broader peaks were observed after irradiation, which indicated changes in the morphology of the copolymer. Through FT‐IR, a slight decrease in the crystallinity of the irradiated EVOH29 was observed at the highest irradiation dose and several bands arise which correspond to the formation of degradation products such as aldehydes and ketones after irradiation. Those radiolysis compounds were identified through gas chromatography coupled to mass spectroscopy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Chitosan graft copolymers‐HA/DBM biocomposites: Preparation, characterization, and in vitro evaluation
Authors: Mohamed Khaled R. , El‐Bassyouni Gehan T. , Beherei Hanan H. 
Published: May 2007

AbstractThe combination of biopolymer with a bioactive component takes advantage of the osteoconductivity and osteoinductivity properties. The studies on composites containing hydroxyapatite (HA), demineralized bone matrix (DBM) fillers and chitosan biopolymer are still conducted. In the present study, the bioactive fillers were loaded onto p(HEMA‐MMA) grafted chitosan copolymer to produce a novel biocomposites having osteoinductive and osteoconductive properties. The produced composites were assessed by TGA, XRD, FTIR, and SEM techniques to prove the interaction between both matrices. In vitro behavior of these composites was performed in SBF to verify the formation of apatite layer onto their surfaces and its enhancement. The results confirmed the formation of thick apatite layer containing carbonate ions onto the surface of biocomposites especially these containing HA‐DBM mixture and pMMA having bone cement formation in their structure. These a novel biocomposites have unique bioactivity properties can be applied in bone implants and tissue engineering applications as scaffolds in future. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Controlled geometry fabrication of polydimethylsiloxane nanofibers for biomimetics
Authors: Trofin Lacramioara , LeDuc Philip R. 
Published: May 2007

AbstractThe ability to have control of fabricated structures on the nanometer size scale is essential in interfacing inorganic technologies with biological systems in many scientific areas including biomimetics and cell topology studies. Here, we developed a simple and efficient method to produce polydimethylsiloxane (PDMS) nanofibers with controlled aspect ratios that could be used in biological studies. As PDMS is a well studied polymer system, this structure would enable a variety of diverse applications. A template synthesis technique was used to create the fibers by molding a polymer solution into an alumina membrane. The pressure and the template surface chemical characteristics were controlled to enable the easy creation of geometric configurations with up to a 30‐fold range of aspects ratios through the use of the same porous alumina template. These fibers can be also used in producing biomimetic synthetic column structures that are found in biological systems such as spider hairs and gecko feet. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Synaptosome behaviour is unaffected by weak pulsed electromagnetic fields
Authors: Aldinucci C. , Carretta A. , Maiorca S. , Rossi V. , Ciccoli L. , Pessina G.P. 
Published: May 2007

AbstractThe present study examined the effect on rat cortical synaptosomes of a 2 h exposure to 50‐Hz electromagnetic fields (EMFs) with a peak magnetic field of 2 mT. We measured modifications of synaptosomal mitochondrial respiration rate, ATP production, membrane potential, intrasynaptosomal Ca2+ concentration and free iron release. The O2 consumption remained unvaried in exposed synaptosomes at about 2 nM O2/min/mg proteins; ATP production was also unchanged. The intrasynaptosomal Ca2+ concentration decreased slowly and there was a slight, but non‐significant, depolarisation of the synaptosomal membrane. Finally, the free iron release by synaptosomal suspensions, a useful predictor of neuro‐developmental outcome, remained unchanged after EMF exposure. On the whole, our results indicate that the physiological behaviour of cortical synaptosomes is not affected by weak pulsed EMFs. Bioelectromagnetics 28:477–483, 2007. © 2007 Wiley‐Liss, Inc.
“Leben heißt ein Kämpfer sein” – Zum Verhältnis von Wissenschaft und Öffentlichkeit am Beispiel der modernen Eisenhüttenkunde an der Technischen Hochschule Aachen
Authors: Krebs Stefan 
Published: May 2007

Abstract“To Live is to be Fighter” – On the Relatioship of Science and Public Illustrated by the Example of Modern Ferrous Metallurgy at the Technical University Aachen. – The contribution pursues the question of how Fritz Wüst, professor of ferrous metallurgy at the Technische Hochschule Aachen (1901–1921), changed the configurations of influential agents, thus readjusting power structures in favour of the institute of metallurgy in Aachen. Science and the public are here understood as resources for one another. Through the establishment of his own technical journals, and cooperation with industry, interest groups, and the politics of Berlin, Wüst mobilised specific public relations for himself, and thus connected the Aachen iron metallurgy multifariously with the social network of the German Empire. He was well able to recognise the sensitive conditions of his times, using them for his own purposes in his lectures and publications. Thus, he stylised modern iron metallurgy to a motivating and formative force for the German Empire's world power ambitions. These politics for science demonstrate how at the institutional and intellectual level, the interweaving of scientific and political goals followed.
Design als ‘mediating interface’ Zur Zeugen‐ und Zeichenhaftigkeit des Radioapparates
Authors: Fickers Andreas 
Published: May 2007

AbstractDesign as Mediating Interface: Historical Evidence and Symbolic Enunciation of the Radio Set. – Based on a case study on the invention of the radio station scale in the late 1920's and early 1930's, this article pleads for an interdisciplinary look at the importance of design as a mediating interface in the production‐consumption junction. In this cultural history perspective on technology, the material artifact matters both as a witness of and a sign for the symbolic meaning and appropriation of the technical object, which transgresses the functional logic of instrumental rationality. In presenting five different perspectives on design offering some alternative looks for a cultural history of technology, this theoretically inspired essay wants to sound the critical potential of a multilayered semantic approach to the radio apparatus as a prominent representation of a radical innovation in media technology.
Large‐scale biodiesel production from microalga Chlorella protothecoides through heterotrophic cultivation in bioreactors
Authors: Li Xiufeng , Xu Han , Wu Qingyu 
Published: May 2007

AbstractAn integrated approach of biodiesel production from heterotrophic Chlorella protothecoides focused on scaling up fermentation in bioreactors was reported in this study. Through substrate feeding and fermentation process controls, the cell density of C. protothecoides achieved 15.5 g L−1 in 5 L, 12.8 g L−1 in 750 L, and 14.2 g L−1 in 11,000 L bioreactors, respectively. Resulted from heterotrophic metabolism, the lipid content reached 46.1%, 48.7%, and 44.3% of cell dry weight in samples from 5 L, 750 L, and 11,000 L bioreactors, respectively. Transesterification of the microalgal oil was catalyzed by immobilized lipase from Candidia sp. 99–125. With 75% lipase (12,000 U g−1, based on lipid quantity) and 3:1 molar ratio of methanol to oil batch‐fed at three times, 98.15% of the oil was converted to monoalkyl esters of fatty acids in 12 h. The expanded biodiesel production rates were 7.02 g L−1, 6.12 g L−1, and 6.24 g L−1 in 5 L, 750 L, and 11,000 L bioreactors, respectively. The properties of biodiesel from Chlorella were comparable to conventional diesel fuel and comply with the US Standard for Biodiesel (ASTM 6751). These results suggest that it is feasible to expand heterotrophic Chlorella fermentation for biodiesel production at the industry level. Biotechnol. Bioeng. 2007; 98: 764–771. © 2007 Wiley Periodicals, Inc.
Surgical treatment and outcome of iatrogenic bile duct lesions after cholecystectomy and the impact of different clinical classification systems
Authors: Bektas H , Schrem H , Winny M , Klempnauer J 
Published: May 2007

Abstract

Background
Different injury patterns of iatrogenic bile duct lesions after cholecystectomy have prompted the proposal of several different clinical classification systems. The aim of this study was to validate these systems comparatively.

Methods
Results after surgical intervention for iatrogenic bile duct lesions in 74 consecutive patients at a tertiary referral centre were reviewed retrospectively. A new classification (Hannover classification) for iatrogenic bile duct lesions is proposed and compared with four other systems using the present clinical data.

Results
Additional vascular lesions were found in 19 per cent. The hospital mortality rate was 3 per cent and the overall hospital complication rate after repair was 26 per cent. Sixteen of 74 patients required early surgical reintervention. The Hannover classification demonstrated a highly significant association between the discrimination of classifiable injury patterns and the different surgical treatments chosen (P &lt; 0·005). The Strasberg and Neuhaus classifications do not consider vascular involvement, whereas the Stewart–Way, Siewert and Neuhaus systems do not discriminate between lesions at or above the bifurcation of the hepatic duct.

Conclusion
Additional vascular involvement and location of the lesion at or above the bifurcation of the hepatic duct have a major impact on the extent of surgical intervention required and should be reflected in any classification of bile duct injuries.
Low‐Temperature Adsorption/Storage of Hydrogen on FAU, MFI, and MOR Zeolites with Various Si/Al Ratios: Effect of Electrostatic Fields and Pore Structures
Authors: Jhung Sung Hwa , Yoon Ji Woong , Lee Ji Sun , Chang Jong‐San 
Published: May 2007

AbstractSeveral zeolites, such as faujasite, mordenite, and ZSM‐5, with various aluminum contents have been used to analyze the effect of aluminum or cation concentration (strength of electrostatic field) on hydrogen adsorption at low temperature. Irrespective of the zeolite structure, the adsorption capacity, isosteric heat of adsorption (−ΔHads), surface coverage, and micropore occupancy increase with increasing aluminum content of a zeolite. Zeolites with a higher amount of aluminum favorably adsorb hydrogen at relatively low pressures. For zeolites with similar aluminum contents, the adsorption capacity, isosteric heat of adsorption, surface coverage, and micropore occupancy are in the order of mordenite>ZSM‐5>faujasite, probably due to differing pore sizes and the presence or absence of pore intersections. This work demonstrates that zeolites with strong electrostatic fields and narrow pores without intersections are beneficial for high hydrogen uptake.