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1.
Bioresour Technol ; 100(8): 2444-51, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19117753

ABSTRACT

Exploitation of olive kernel for bioenergy production, with respect to the green house gases (GHGs) mitigation, is the main aim of this work. In this study, olive kernels were used as a solid biofuel, and high temperature steam gasification (HTSG) was investigated, in the fixed bed unit at KTH Sweden, with regard to hydrogen maximization in the produced gasification gas. Experiments were carried out in a temperature range of 750-1050 degrees C, with steam as the gasifying agent. The behaviour of olive kernels, under residence times from 120 up to 960 s, has been studied. At 1050 degrees C, a medium to high calorific value gas was obtained (LHVgas=13.62 MJ/Nm3), while an acquired H2/CO molar ratio equal to four proved that olive kernel HTSG gasification could be an effective technology for a hydrogen-rich gas production (approximately 40%vv H2 in the produced gasification gas at 1050 degrees C). The produced char contained 79%ww of fixed carbon, low chlorine and sulphur content, which enables it for further re-use for energetic purposes. Tar content in the produced gas at 750 degrees C was 124.07 g/Nm3, while a 1050 degrees C at 79.64% reduction was observed and reached the value of 25.26 g/Nm3.


Subject(s)
Gases/metabolism , Hot Temperature , Olea/metabolism , Steam , Benzene/analysis , Carbon Dioxide , Carbon Monoxide , Hydrogen , Methane/metabolism , Naphthalenes/analysis , Time Factors , Toluene/analysis
2.
Nature ; 420(6915): 482-5, 2002 Dec 05.
Article in English | MEDLINE | ID: mdl-12466837

ABSTRACT

Intense radiation from lasers has opened up many new areas of research in physics and chemistry, and has revolutionized optical technology. So far, most work in the field of nonlinear processes has been restricted to infrared, visible and ultraviolet light, although progress in the development of X-ray lasers has been made recently. With the advent of a free-electron laser in the soft-X-ray regime below 100 nm wavelength, a new light source is now available for experiments with intense, short-wavelength radiation that could be used to obtain deeper insights into the structure of matter. Other free-electron sources with even shorter wavelengths are planned for the future. Here we present initial results from a study of the interaction of soft X-ray radiation, generated by a free-electron laser, with Xe atoms and clusters. We find that, whereas Xe atoms become only singly ionized by the absorption of single photons, absorption in clusters is strongly enhanced. On average, each atom in large clusters absorbs up to 400 eV, corresponding to 30 photons. We suggest that the clusters are heated up and electrons are emitted after acquiring sufficient energy. The clusters finally disintegrate completely by Coulomb explosion.

3.
J Am Acad Dermatol ; 43(6): 1130-4, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11100038

ABSTRACT

The association of maternal pemphigus foliaceus (PF) with neonatal PF is rare and may be secondary to transplacental passage of PF autoantibodies. We describe a 25-year-old patient with PF who was delivered of two consecutive babies, one with classic skin lesions of PF and another that was normal. The neonate with PF was born when the mother had widespread skin disease; the normal newborn was born when the mother was in partial remission. The titers of PF autoantibodies were higher in the mother's serum and the cord serum of the baby with PF than in the mother during partial remission and the unaffected baby. The mother and affected baby had autoantibodies to desmoglein 1. Furthermore, cord blood from the baby with PF induced skin disease when injected into mice. In this case, maternal PF was associated with neonatal PF when the titers of maternal anti-desmoglein 1 autoantibodies were elevated. The cutaneous disease in neonatal PF is due to anti-desmoglein 1 autoantibodies.


Subject(s)
Autoantibodies/analysis , Immunity, Maternally-Acquired , Pemphigus/immunology , Pregnancy Complications, Infectious/immunology , Pregnancy Outcome , Adult , Animals , Female , Fetal Blood/immunology , Humans , Infant, Newborn , Maternal-Fetal Exchange , Mice , Mice, Inbred BALB C , Pemphigus/diagnosis , Pregnancy , Pregnancy Complications, Infectious/diagnosis
4.
Rev Rhum Engl Ed ; 65(3): 165-72, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9574473

ABSTRACT

PURPOSE AND METHODS: We investigated the expression and localization of topoisomerase I by Western blot and indirect fluorescent antibody assay, respectively, using anti-Scl-70/topo I from patients with diffuse scleroderma. The contribution of topoisomerase I to DNA replication was assessed using cells treated with the topoisomerase I inhibitor camptothecin. RESULTS: Scl-topo I was detected at all cell cycle phases as a single immunoreactive band of 100 kDa. Extracts from cells in the S phase contained the largest amount of immunoreactive Scl-70/topo I. Variations in the subcellular distribution of Scl-70/topo I were seen throughout the cell cycle, with a speckled nucleoplasmic distribution during G1 contrasting with concentration within the nucleolus during S. Camptothecin exposure blocked topoisomerase I expression and caused a significant decrease in DNA production. CONCLUSION: These data suggest (1) that topomerase I is active mainly during the S phase and contributes to DNA replication, and (2) that topoisomerase I may be involved in ribosomal gene transcription.


Subject(s)
DNA Topoisomerases, Type I/metabolism , Nuclear Proteins/metabolism , Antineoplastic Agents, Phytogenic/pharmacology , Autoantigens/analysis , Autoantigens/genetics , Autoantigens/metabolism , Blotting, Western , Camptothecin/pharmacology , Cell Cycle/drug effects , Cell Cycle/immunology , Cell Division/drug effects , DNA Replication/drug effects , DNA Replication/immunology , DNA Topoisomerases, Type I/analysis , Fluorescent Antibody Technique, Indirect , Humans , Hydroxyurea/pharmacology , Mitotic Index , Nuclear Proteins/antagonists & inhibitors , Nuclear Proteins/genetics , Nucleic Acid Synthesis Inhibitors/pharmacology , S Phase , Scleroderma, Systemic/enzymology , Scleroderma, Systemic/metabolism , Topoisomerase I Inhibitors , Tumor Cells, Cultured/chemistry , Tumor Cells, Cultured/cytology , Tumor Cells, Cultured/enzymology
5.
J Invest Dermatol ; 109(4): 592-6, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9326396

ABSTRACT

Pemphigus vulgaris is an autoimmune bullous disorder characterized by autoantibodies directed against desmoglein 3. A group of 19 pemphigus vulgaris sera were characterized by immunoblotting, immunofluorescence, immunoprecipitation, and the passive transfer mouse model. The aim of these studies was to determine the specificity of the autoantibody response in these patients. All patients had clinical and histologic evidence of pemphigus vulgaris. Fogo selvagem sera (n = 8), bullous pemphigoid sera (n = 8), antinuclear antibodies positive sera from patients with lupus erythematosus (n = 2), and normal human sera (n = 8) were used as controls. All pemphigus vulgaris patients showed titers of IgG autoantibodies by indirect immunofluorescence > or = 1:60, predominantly of the IgG4 subclass and immunoprecipitated recombinant desmoglein 3 expressed in the baculovirus system. Patients with disease localized to the mucous membranes showed no reactivity with desmoglein 1 and only one had weak reactivity with mouse skin by indirect immunofluorescence (titer = 1:20). Sera of four of these mucosal patients were tested in the mouse model and three of four did not elicit skin or mucosal disease in the animals. In contrast, sera from all seven patients with disease involving the skin and mucous membranes (generalized disease) produced disease in neonatal mice. In one patient the disease evolved from pure mucosal involvement associated with anti-desmoglein 3 antibodies to a disorder involving mucosas and skin. This transition was associated with the appearance of anti-desmoglein 1 antibodies in the patient's serum. These studies indicate that the autoantibody response in pemphigus vulgaris is heterogeneous. Epitopes recognized by some pemphigus vulgaris sera are species specific and others may be mucosal specific.


Subject(s)
Autoantibodies/analysis , Pemphigus/immunology , Animals , Animals, Newborn , Autoantibodies/immunology , Cadherins/immunology , Cross Reactions , Cytoskeletal Proteins/immunology , Desmoglein 1 , Desmoglein 3 , Desmogleins , Desmoplakins , Fluorescent Antibody Technique, Indirect , Humans , Immunoglobulin G/immunology , Mice/immunology , Mice, Inbred BALB C , Mucous Membrane
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