bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative XPS and AFM surface analysis: Study of a patched gold overlayer on graphite
Authors: Gollion Ph. , Grenet G. 
Published: December 2004

AbstractA patched gold overlayer obtained by thermal evaporation on graphite was investigated by x‐ray photoelectron spectroscopy (XPS) and by atomic force microscopy (AFM). The fraction of the substrate area covered by gold and the overlayer thickness are deduced from XPS angular measurements. These results are compared with topo‐graphic data as given by AFM.
Direct morphological study of metal/polymer interfaces by scanning force microscopy
Authors: Akari Sabri , Esselink Eddy , Hadziioannou Georges 
Published: December 2004

AbstractUsing a scanning force microscope, direct imaging of the metal/polymer interface was achieved for the first time by removing the evaporated metal film from the deposited polymer and imaging the side that was exposed to the polymer. This technique allows direct sight of the metal/polymer interface and provides information about the possible effects related to metal deposition on polymers. For comparison, two different metals, gold and aluminium, with fairly different physical properties were evaporated on a spin‐coated poly‐3‐octylthiophene polymer. While the gold film exhibits fine granulates forming a semi‐homogeneous film, the aluminium film shows large elongated protrusions forming a network structure.
Measuring the bulk flow properties of PVC resins
Authors: Schwaegerle Paul R. 
Published: December 2004

AbstractThe flow characteristics of PVC resin are often judged by measuring the time required for a given amount of dry resin to flow through a standard funnel. However, considerable variation in test results have been found between laboratories though the test is conducted well within the procedural limits of ASTM 1895‐69, “Apparent Density, Bulk Factor and Pourability of Plastic Materials.” An examination has been made of the effects of funnel hole size, funnel alignment, its type metal and wall surface smoothness, filling technique, static generated, and degree of vibration. It was found that six of these seven variables need critical control, while one (alignment) has no measurable effect. It is suggested that the data presented be used for the development of an improved ASTM test for measuring the flowability of PVC resins.
Processability of rigid PVC compounds II. Comparions of extrusiometric and mixing head data. Effect of composition variables
Authors: Pukánszky Béla , Nagy Tibor Tamás , Turcsányi Béla , Tüdõs Ferenc , Krall György , Papp‐Tölgyesi E. 
Published: December 2004

AbstractVarious formulations of unplasticized PVC dry blends were investigated by extrusiometer and laboratory batch mixer (mixing chamber). Torque versus time curves of the mixing chamber experiments were characterized by three, essentially independent data: fusion time, equilibrium torque, and stability time, corresponding to the three distinct phases of the processing. Fair correlation was found between fusion characteristics of the compound and the energy required for its processing in the extrusiometer. The effect of composition on extrusiometric and mixing chamber data was investigated by multiple linear regression technique. The results allow prediction of the effect of recipe changes.
Stress cracking of rigid polyvinyl chloride by plasticizer migration
Authors: Lacatus Emilia , Summers James W. 
Published: December 2004

AbstractEnvironmental stress cracking (ESC) (failure caused by crack and craze formation at a stress less than the yield stress) reduces the service life of many plastic products. This paper is concerned with ESC of rigid PVC products which are in contact with a plasticized PVC material. The ESC affect (as measured by elongation to break) is reduced at faster strain rates and by higher plasticizer viscosity, which suggests a mechanism requiring flow of plasticizer into a growing craze. Well fused (gelled) PVC made at a higher melt temperature slowed but did not eliminate environmental stress cracking. Rubber impact modifier added to the rigid PVC had no effect on ESC. Environmental stress cracking can be avoided by using flexible PVC that has a non‐migrating plasticizer or by designing the product so that rigid PVC is not stressed while in contact with plasticized PVC.
Suspension stabilizers for PVC production II: Drop size distribution
Authors: Nilsson Holger , Norviit Toomas , Silvegren Christer , Törnell Bertil 
Published: December 2004

AbstractThe drop size distribution of vinyl chloride in water emulsions has been studied using a photographic technique. A large difference in coalescence stability was observed between emulsions stabilized by a poly(vinyl alcohol), Rhodoviol 5/270, and those stabilized by a cellulose ether, Methocel MF50. Experiments simulating the transport of a monomer soluble initiator to the monomer phase of a coalescence stable vinyl chloride in water emulsion showed that the manner of introducing the initiator may have large consequences on the polymerization process.
Dark time yellowing of white rigid vinyl outdoor weatherable compounds
Authors: Morris Raymond A. , Prejean Thomas G. , Green John Glass 
Published: December 2004

AbstractWhite PVC siding which has been exposed to sunlight will after removal from the sunlight develop a darker color (yellow‐brown). The longer this sample remains unexposed to sunlight the greater the color development. Testing has indicated that one or more photochemical mechanisms are occurring during this color development. A sample which appears yellow upon arrival at the home location after outside exposure can be re‐whitened by re‐exposing the sample to sunlight. Drastic color change will occur within a short period of time, usually less than 72 hours. This sample will have attained its white color with little or no yellowing visible when an original unexposed sample is held next to it. Testing conducted at an Arizona test site has confirmed these theories. Six months and one year weathered white siding samples, when measured at the test site, both experimental and commercial, showed that when the weathered samples are removed from the test racks and tristimulus values are measured daily, marked color changes occur rapidly. This paper addresses data which indicate that color development does occur but only in the very thin surface (5 to 10 micron layer) of the weathered samples. If these samples are washed and the abrasive action is sufficient to remove the surface layer, color development will no longer occur during non‐exposure to sunlight.
Thermodynamic interactions and nonlinear rheological properties of plasticized polyvinyl chloride
Authors: Foss Peter H. , Shaw Montgomery T. 
Published: December 2004

AbstractThe nature of thermodynamic interactions in plasticized semicrystalline materials has a profound effect on the rheological properties. In this work we investigated the effect of mixing thermodynamics on the linear and nonlinear rheological properties of plasticized poly(vinyl chloride). The stress‐dependent creep compliance has been modeled in terms of stress, temperature, concentration, and thermodynamic interaction strength.
Rheology of PVC. Part 5: Melt elasticity
Authors: Utracki L. A. 
Published: December 2004

AbstractThe behavior of PVC changes drastically with the temperature and the method of sample preparation. In the steady‐state shear mode, upon a decrease of the rate of deformation, the data may show either a steady increase of the shear viscosity or a leveling off to a Newtonian plateau. In the dynamic test mode, both the storage modulus, G′, and the loss modulus, G″, show an effect of the yield stress. Only at temperatures above 210°C are flow curves normal for polymer melts obtained. Rigid and nonrigid PVC formulations have been tested in Weissenberg Rheogoniometer, using steady‐state or dynamic test modes at temperatures from 140 to 220°C. It was observed that yield affects elasticity more (measured by the first normal stress difference or the storage modulus) than viscosity (expressed by the shear stress or the loss modulus). The corrected for yield plots of elastic vs. viscous parameter can be easily interpreted in terms of a composite flow.
Correlations between extrusion and injection molding process variables for PVC dry blends
Authors: Dalal V. F. , Palit K. 
Published: December 2004

AbstractAlthough thermoplastic extrusion and injection molding have been extensively studied by a large number of authors, very little is known about the correlations between the extrusion and injection molding process variables. This paper describes the various comparable process variables between extrusion and injection molding of PVC dry blends. The Brabender extruder of 19 mm diameter and 25:1 length to diameter ratio and the Szekeley reciprocating single screw injection molding machine were used. PVC dry blends of industrial importance were prepared using a high speed mixer. The four mix formulations based on a commercial grade of PVC were used. Process variables studied during the injection molding were the melt temperature near the nozzle, injection pressure, injection speed, and energy consumption. Process variables studied during extrusion were the melt pressure at the die, power consumption, and the melt temperature at the die orifice. The correlations between the extrusion and injection molding process variables for PVC dry blends have been established.
Selecting operating conditions for PVC plastisol fusion ovens
Authors: Poppe A. C. 
Published: December 2004

AbstractGelation and ultimate fusion of layers of plastisol is a major step in producing finished spread‐coated vinyl products. An analysis of the process has been made, concentrating on heat‐up, required conditions for adequate fusion, and the associated plasticizer evaporation losses. It is further shown how the developed model can be used to help select optimal process conditions.
Vinyl composites—fiberglass reinforced PVC
Authors: Summers James W. , Faber Edward , Kinson Philip L. , Rabinovitch Elvira B. 
Published: December 2004

AbstractGlass fiber reinforced PVC has several distinctive and useful properties. Its tensile strength can be twice that of unreinforced PVC. Excellent coupling of the glass fibers to the PVC matrix is required for good retention of tensile strength when exposed to warm water, Its modulus can be twice that of unreinforced PVC and equal to that of wood. PVC's high load carrying capability is not significantly increased to higher temperatures by adding glass fibers as judged by its 264 psi heat deflection temperature. However, by changing the polymeric matrix, glass reinforced vinyl with an increased HDT of 86°C has been produced for higher use temperature. The coefficient of linear thermal expansion of PVC can be cut in half by the addition of glass fibers and has a coefficient equal to that of aluminum. Glass fiber reinforced PVC has exceptionally good resistance to crack propagation and resists shattering as judged by sawing, punching, stapling, and hammering. When properly formulated for weathering resistance, glass fiber reinforced PVC has good color retention, impact retention, and outstanding dimensional stability. As for all glass fiber reinforced plastics, processing equipment must be built for high abrasion resistance for long economical manufacturing runs.
Infection of central nervous system after kidney transplantation
Authors: Lezaic V. , Radivojevic D. , Blagojevic‐Lazic R. , Djukanovic Lj. 
Published: December 2004

Editor's comment:Central nervous system (CNS) infection remains an important problem among transplant recipients. The recent review by Singh and Husain and this letter from Yugoslavia underline the following: a subacute‐chronic presentation is typical of fungal and bacterial CNS infections; early diagnosis is the key to effective therapy; the indication for a CNS evaluation is an unexplained headache, particularly in conjunction with a change in the level of consciousness (classical meningeal findings may not be present in a timely fashion); and the minimum CNS evaluation is a cranial computerized tomographic (CT) scan and a lumbar puncture. Robert H. Rubin, MD
Hamster‐to‐rat bone marrow xenotransplantation and humoral graft vs. host disease
Authors: Miki Toshio , Lee Yi‐Horng , Tandin Alessia , Subbotin Vladimir , Goller April , Kovscek Annastasia , Fung John J. , Valdivia Luis A. 
Published: December 2004

Abstract: Bone marrow transplantation (BMT) may induce tolerance across xenogeneic barriers. We have established a xenogeneic BMT model where hamster BM is transplanted into splenectomized LEW rat recipients resulting in high levels of engraftment. Unfortunately, graft vs. host disease (GVHD) with severe dermatitis developed in all rat recipients. We were successful in treating or preventing the dermatitis of this xenogeneic GVHD by the use of the T‐cell suppressant tacrolimus. However, this compound did not prevent the development of a fatal liver injury in the rat recipients. This study was designed to elucidate the pathogenesis of this liver injury appearing in T‐cell suppressed rat recipients of hamster BM.Splenectomized and irradiated (10 Gy) LEW rats received 300 × 106 unfractionated hamster BM cells. These BMT recipients were divided in 3 groups: Group I recipients (n = 8) did not receive further immunosuppression. Group II animals (n = 10) received tacrolimus 1 mg/kg/d for 7 d. Group III recipients (n = 6) were given the same daily dose of tacrolimus on a long‐term basis. Chimerism was detected by flow cytometry. Cytotoxicity of recipient's sera against rat and hamster lymph node cells was measured by complement‐dependent cytotoxicity (CDC) test. Immunofluorescence was used to detect hamster antirat antibodies on several recipient organs.In Group I, 2 out of 8 animals engrafted (25%) and survived for a median of 21 d showing the severe dermatitis characteristic of GVHD. In group II (n = 10), 9/10 rat recipients engrafted (90%) and survival was increased to a median of 53.7 days. However, these surviving recipients developed fatal GVHD not different from that observed in Group I recipients. All animals in Group III (n = 6) engrafted and did not show the characteristic dermatitis of GVHD. Their survival, however, was shortened to a median of 30.3 d by a severe liver injury. This injury was characterized by hepatocyte necrosis in zones 1 and 2 with polymorphonuclear (PMN) cell infiltration. Deposits of hamster immunoglobulins were present around the necrotic areas and in the portal veins. Moreover, antirat antibodies appeared in the circulation. These antibodies were sensitive to dithiothreitol (DTT) treatment indicating that they were of the IgM class.This study shows that xenogeneic GVHD may have a dual presentation in the hamster‐to‐rat model: a classical cellular GVHD not distinct to the allogeneic one and a humoral GVHD affecting solely the recipient liver. The degree of humoral injury is potentiated by T‐cell suppression.
Nutritional supplements in Norwegian elite athletes—impact of international ranking and advisors
Authors: Sundgot–Borgen J. , Berglund B. , Torstveit M. K. 
Published: December 2004

The aims of this study were to investigate (a) the use of nutritional supplements (NS) (vitamins, minerals, Omega 3, antioxidants, ginseng, amino acids, Creatine and energy supplements) in elite athletes of different international ranking (b) why athletes are using NS, and (c) who recommends the elite athletes to use NS.The total population of elite athletes in Norwegian National Teams (n = 1620, 960 males and 660 females aged 15–39 years) and randomly selected (n = 1681) (916 males and 765 females) controls from the general population, were given a questionnaire including questions about use of nutritional supplements (NS), and from whom athletes had received information about nutrition and recommendations to use NS. The response rate was 76% for male and 92% for female athletes and 75% and 81% for male and female controls, respectively. A similar percentage of female athletes (54%) and controls (52%) reported use of one or more NS, but more male athletes (51%) than male controls (32%) used NS (P < 0.001). However, independent of gender, more athletes as compared to controls used minerals (males 26% vs. 8%; females 42% vs. 20%), amino acids (males 12% vs. 4%; females 3% vs. 0), and Creatine (males 12% vs. 2%; females 3% vs. 0). A lower percentage of NS users were observed in the best female athletes (52%) as compared to female athletes with less experience of international competition (73%) (P < 0.01). In male athletes, NS use was independent of international ranking (49%−53%). The coach was the main advisor for use of NS for both male (58%) and female athletes (52%). For male and female athletes, the main reason for using NS was that they felt it was needed in addition to their daily intake (56% and 67%, respectively). Forty one percent of the male and 37% of the female athletes using NS felt they were well informed about nutrition in general and NS. However, 8% of the NS users did not know whether the NS they used was doping classified or not. In conclusion: we found that a similar percentage of female elite athletes and controls, but a higher percentage of male elite athletes than controls, reported the use of NS. There was a lower percentage of NS use among the top female athletes, but not the top male athletes as compared to the less successful elite athletes. The coach was the main advisor for NS use both for male and female elite athletes.
Evaluation of a new whole‐blood filter that allows preparation of platelet concentrates by platelet‐rich plasma methods
Authors: Lozano Maria L. , Pérez‐Ceballos Elena , Rivera Jose , Paunovic Dragica , Candela Maria J. , Vicente Vicente 
Published: December 2004

BACKGROUND: A novel WBC‐reduction in‐line whole‐blood (WB) filter that does not retain platelets was evaluated to assess the filtration performance and, after processing WB by the platelet‐rich plasma (PRP) method, to analyze the storage quality of filtered platelet concentrate (PC) units.STUDY DESIGN AND METHODS: To analyze the filter retention, blood was collected from random donors into quadruple blood packs with an integral in‐line filter (Imuflex WB‐SP, Terumo; n = 25) or in standard triple bag systems (n = 30). To assess the in vitro storage characteristics of platelets, 26 WB units were pooled in pairs and redistributed into 13 units that underwent WBC reduction and 13 units that were not WBC reduced. In all cases, WB was separated into RBCs, PCs, and plasma by the PRP method and platelet function was compared.RESULTS: The filtration procedure led to RBC and PC WBC‐reduced products that met the AABB and European requirements. The average filtration time was 30 minutes, the filter retained about 45 mL of WB, and there was no further loss of RBCs during the fractionation procedure. In vitro PC storage characteristics of the filtered units were similar to those of the nonfiltered units.CONCLUSION: A 4‐ and 3‐log WBC reduction was observed in RBC and PC units that were produced by the PRP method, with a mean residual WBC content of 0.24 ± 0.38 × 106 and 0.02 ± 0.03 × 106 per unit, respectively. The procedure, performed under relatively simple logistics, results in good‐quality, standard components that may reduce costs and ease the process of WBC reduction in transfusion services.
Expression of CD137 (4‐1BB) on Human Follicular Dendritic Cells
Authors: Lindstedt M. , Johansson‐Lindbom B. , Borrebaeck C. A. K. 
Published: December 2004

AbstractFollicular dendritic cells (FDCs) are the antigen (Ag)‐trapping accessory cells of the germinal centres (GCs), essential for the development of humoral immune responses and memory. FDCs reside in the microenvironment of secondary lymphoid tissue where Ag‐activated B cells expand, and undergo isotype switching and affinity maturation prior to becoming memory B cells. In addition to delivering Ag, FDCs also provide potent nonspecific accessory signals to the B cells, which are important for the GC reaction. In this report, we show that human tonsilar FDCs express the costimulatory molecule CD137. Surface expression of CD137 on FDCs was confirmed by immunofluorescent labelling and fluorescence‐activated cell sorter analysis. CD137 was also highly expressed by the human cell line HK, which displays many characteristics of in vivo FDCs. The interaction between B cells and FDCs is essential for the GC reactions, and our finding suggests that CD137 plays a role in FDC‐regulated B‐cell responses.
The Formyl Peptide N‐Formyl‐methionyl‐leucyl‐phenylalanine Downregulates the Expression of FcγRs in Interferon‐γ‐Activated Monocytes/Macrophages In Vitro and In Vivo
Authors: Beigier‐Bompadre M. , Barrionuevo P. , Alves‐Rosa F. , Rubel C. J. , Palermo M. S. , Isturiz M. A. 
Published: December 2004

Abstract N‐Formyl peptides are cleavage products of bacterial and mitochondrial proteins that have pro‐inflammatory activities and play an important role in antibacterial host defence. FcγRI is a receptor for the Fc portion of immunoglobulin G expressed in monocytes that mediates cytotoxicity and is upregulated by interferon‐γ (IFN‐γ) and interleukin‐10 (IL‐10). In this report, we demonstrate that N‐formyl‐methionyl‐leucyl‐phenylalanine (FMLP) downregulates the expression of FcγRI in IFN‐γ‐treated monocytes, but not in IL‐10‐treated monocytes. We determine that supernatants obtained from monocytes treated with IFN‐γ and then exposed to FMLP induce the downregulation of FcγRI in naïve monocytes. This effect is abrogated by the protease inhibitors phenylmethylsulphonyl fluoride and phosphoramidon, which inhibit serine and metalloproteases, respectively. Supernatants from FMLP‐treated neutrophils also induce the downregulation of FcγRI, when added to naïve monocytes. Similar observations were obtained in vivo in a mouse model of chronic inflammation. In vivo, FMLP also downregulates the expression of FcγRs in IFN‐γ‐activated macrophages. Our results support the existence of a new mechanism through which FMLP could modulate the activity of monocytes/macrophages during bacterial infections.
Cross‐Reaction of Anti‐Simian Immunodeficiency Virus Envelope Protein Antibodies with Human Immunoglobulins
Authors: Zigment‐Reed L. M. , Fairley C. A. , Chow K. H. , Yucel F. , Cirakoglu B. , Thompson K. M. , Suleyman S. , Pinchuk G. V. 
Published: December 2004

AbstractIt has been recently established that retroviral envelope proteins (REPs) have structural features similar to those of immunoglobulins (Igs). In this study, we asked whether anti‐REP antibodies cross‐react with human Igs (hIgs). To this end, murine monoclonal antibodies (mMoAbs) that had been raised against a simian immunodeficiency virus (SIV) envelope protein, SIVMac251gp120, were screened for their ability to react with human monoclonal Igs (HMIgs). We show that two HMIgs, RFSJ2 (a rheumatoid factor) and PAMLN6 (a human anti‐hIg V region antibody), but not a number of other HMIgs, could be weakly, but consistently, bound by anti‐SIVMac251gp120 mMoAbs KK17 and KK46, as judged by indirect enzyme‐linked immunosorbent assay and a liquid‐phase inhibition immunoassay. Both mMoAbs are specific to amino acid residues in the V3 loop of the SIVMac251gp120. The RFSJ2 Ig heavy‐chain V region (VH) is coded in part by a human VH gene, VH3–30.3 and includes the idiotope 7B4 (NKYY), which was previously shown to be present in the gp120 protein of a number of HIV‐2 and SIV strains. However, an entirely different VH gene codes the PAMLN6 VH region, opening the possibility that epitope(s) shared between SIVMac251gp120 and hIgs may not be limited to the 7B4 idiotope.