bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioleaching of copper and other metals from low‐grade oxidized mining ores by Aspergillus niger
Authors: Mulligan Catherine N , Kamali Mahtab 
Published: January 2005

AbstractA study was initiated to determine the feasibility of using the fungus Aspergillus niger for bioleaching metals from oxide low‐grade ore. Large quantities of the metals are embodied in the low‐grade ores and mining residues that can be recovered. Presently available techniques (pyrometallurgical and hydrometallurgical) are expensive or may have a negative impact on the environment. An oxidized mining ore containing mainly copper (7245 mg kg−1 residue) was studied. In this study, the fungus A niger produced a variety of organic acids. Addition of small quantities of sulfuric acid enhanced the organic acids, efficiency. Various agricultural wastes were evaluated as substrates and a maximum solubilization of 68% for copper for a medium containing potato peels was achieved. In conclusion, leaching of copper from a mining ore is technically feasible using A niger. Further research must be performed to increase the rate of copper removal. Copyright © 2003 Society of Chemical Industry
Modelling aspects of the biotechnological valorization of raw glycerol: production of citric acid by Yarrowia lipolytica and 1,3‐propanediol by Clostridium butyricum
Authors: Papanikolaou Seraphim , Aggelis George 
Published: January 2005

AbstractRaw glycerol, produced in significant quantities during several industrial processes, could be further considered as a potential substrate for microbial conversions. In the present report, modelling approaches are used in order to quantify the kinetic behavior of microorganisms capable of producing growth‐ and non growth‐associated metabolites when cultivated on raw glycerol. Citric acid production by Yarrowia lipolytica strain ACA‐DC 50109 was successfully simulated by Monod‐, Verhlust‐ and Williams‐type models, while the optimized parameter values were found to be similar to those experimentally measured. It has been demonstrated that the production of citric acid from raw glycerol, in terms of specific production rate and conversion yield, was similar or even better as compared with that obtained during cultivation of yeasts or molds on various conventional (eg sugar‐based) media. The production of 1,3‐propanediol by Clostridium butyricum strain F2b from raw glycerol was successfully simulated by a Contois‐type model. It was found that the maximum theoretical 1,3‐propanediol productivity was comparable with the highest one achieved during growth of various bacterial strains on pure glycerol in batch and continuous cultures. Raw glycerol could be used as an alternative substrate for citric acid and 1,3‐propanediol production, and possibly for other microbial products. Copyright © 2003 Society of Chemical Industry
Variation of intraparticle diffusion parameter during adsorption of p‐chlorophenol onto activated carbon made from apricot stones
Authors: Koumanova B , Peeva P , Allen SJ 
Published: January 2005

AbstractThe adsorption of para‐chlorophenol onto an active carbon made from waste apricot stones has been studied. The batch kinetic adsorption processes have been measured for a range of system variables including agitation rate, initial concentration of para‐chlorophenol, mass of carbon and particle size of carbon. The extent of adsorption is reported as plots of solid phase concentration against the square root of time. An intraparticle diffusion parameter is used to describe the mass transfer within the adsorbent. This parameter varies with the square root of time and can be related to the type of structure which occurs within an activated carbon. A correlation is proposed relating the process variable with the intraparticle diffusion parameter in each of the three mass transfer regions. Copyright © 2003 Society of Chemical Industry
Immunochemical detection of Lonomia obliqua caterpillar venom in rats
Authors: Da Silva Gustavo Henrique , Panunto Patrícia Costa , Hyslop Stephen , Da Cruz‐Höfling Maria Alice 
Published: January 2005

AbstractSevere cases of human envenoming by caterpillars of the saturniid moth Lonomia obliqua in Brazil can result in renal damage, leading to renal failure, and intracerebral hemorrhaging. In this work, we used immunohistochemical staining with rabbit antiserum raised against L. obliqua venom to examine venom distribution in selected tissues of the brain (cerebellum and hippocampus), kidneys, and liver of male Wistar rats injected with a single dose of venom (200 μg/kg, i.v.) and sacrificed 6, 18, 24, and 72 hours later. The immunolabeling of GFAP was also examined to assess the venom effects on perivascular astrocytic end‐feet in the microvasculature of the hippocampus and cerebellum. Venom was detected in the kidneys (6 and 18 hours) and in the liver (6 hours) but not in the brain at any of the time intervals examined. In contrast, immunolabeling for GFAP revealed astrogliosis in the cerebellum and enhanced expression of this protein in the glial processes of the cerebellum and hippocampus, with a maximum response from 24 hours onwards. The high immunoreactivity seen in the kidneys agreed with the renal damage and dysfunction reported for some patients. The lack of venom detection in the brain, despite the altered expression of GFAP in astrocytes, suggested either that the venom does not enter this organ or that its entrance is transient and fast. Alternatively, the circulating venom may induce the release of mediators that could serve as second messengers to provoke the late astrocytic reactivity and astrogliosis. It is possible that both of these mechanisms may contribute to the effects observed. Microsc. Res. Tech. 65:276–281, 2004. © 2005 Wiley‐Liss, Inc.
GFAP immunoreactivity and transcription in trigeminal and dental tissues of rats and transgenic GFP/GFAP mice
Authors: Byers Margaret R. , Maeda Takeyasu , Brown Angus M. , Westenbroek Ruth E. 
Published: January 2005

AbstractSensory mechanisms in teeth are not well understood and may involve pulpal–neural interactions. Tooth cells that proliferate in vitro have polyclonal immunoreactivity (IR) for glial fibrillary acidic protein (GFAP), growth‐associated protein (GAP‐43), and vimentin, plus glial‐like ion channels. Here, we analyzed GFAP‐IR patterns in dental and trigeminal tissues of rats, for comparison with green fluorescent protein (GFP) associated with GFAP transcription in transgenic mice, in order to better characterize glial‐like cells in dental tissues. Astrocytes, ganglion satellite cells, and epineurial Schwann cells were demonstrated by anti‐GFAP antibodies and GFP‐GFAP, as expected. Odontoblasts did not stain by any of these methods and cannot be the glial‐like cells. Fibroblasts and undifferentiated mesenchymal cells in pulp had polyclonal GFAP‐IR and vimentin‐IR, while nerve fibers reacted only with polyclonal antibody. Some Schwann cell subtypes in trigeminal nerve and oral mucosa were positive for GFP and for polyclonal anti‐GFAP, but not for monoclonal antibody. In pulp almost all Schwann cells were unstained, but many Schwann cells in periodontal ligament had polyclonal GFAP‐IR. These results show greater heterogeneity for Schwann cells than expected, and suggest that the glial‐like pulp cells are fibroblasts and/or undifferentiated mesenchymal cells or stem cells. We also found that polyclonal GFAP revealed intermediate filaments in preterminal sensory nerve fibers, thereby providing a useful marker for that neural subregion. GFP transcription by some Schwann cell subtypes in oral mucosae and trigeminal nerve, but not trigeminal root was a novel finding that reveals more complexity in peripheral glia than previously recognized. Microsc. Res. Tech. 65:295–307, 2004. © 2005 Wiley‐Liss, Inc.
Method for localization of sialic acid on cell surface and cell interior in peripheral blood: A pilot study
Authors: Pönniö Maritta , Soukka Jori , Sillanaukee Pekka , Franck Johan , Seveus Lahja 
Published: January 2005

AbstractThis article presents a method for identification and localization of cell surface and intracellular sialoglycoconjugates of peripheral blood cells. To reveal cell surface conjugates, a sample of peripheral blood was incubated with lectin after centrifugation and rinsing. For intracellular localization in leukocytes, RBCs were lysed and the membranes were permeabilized prior to cytochemical reaction. Fluorescein isothiocyanate conjugated lectins were used for visualization in fluorescence microscope. All lectins bound specifically to the surface of erythrocytes. Confocal microscopy showed surface and intracellular labeling of permeabilized leukocytes. A part of the signal in eosinophils originated from binding of anionic fluorophore to cationic granular proteins. Microsc. Res. Tech. 65:292–294, 2004. © 2005 Wiley‐Liss, Inc.
Bioimaging TOF‐SIMS of tissues by gold ion bombardment of a silver‐coated thin section
Authors: Nygren Håkan , Johansson Bengt R. , Malmberg Per 
Published: January 2005

AbstractThe imaging time‐of‐flight secondary‐ion‐mass‐spectrometry (TOF‐SIMS) method was utilized to address the problem of cholesterol localization in rat tissues. Rat kidneys were fixed, cryoprotected by sucrose, frozen, sectioned by cryoultramicrotomy, and dried at room temperature. The samples were either covered with a thin silver layer or analyzed uncovered in an imaging TOF‐SIMS instrument equipped with an Au‐source. The yield of desorbed secondary ions for some species was up to 600‐fold higher after silver coating of the samples. Reference samples of cholesterol were silver‐coated and analyzed by TOF‐SIMS to define significant peaks, specific for cholesterol. Such peaks were found at m/z = 386 (C27H46O+), m/z = 493 (C27H46O107Ag+), m/z = 495 (C27H46O109Ag+), m/z = 879 (C54H92O2107Ag+), and m/z = 881 (C54H92O2109Ag+). The silver‐cationized cholesterol (493 ≤ m/z ≤ 495) signal was localized by imaging TOF‐SIMS in the kidney sections and showed a high cholesterol content in the kidney glomeruli. A more diffuse distribution of cholesterol was also found over areas representing the cytoplasm or plasma membrane of the epithelial cells in the proximal tubules of rat kidney. Microsc. Res. Tech. 65:282–286, 2004. © 2005 Wiley‐Liss, Inc.
Technique to quantify local clustering of synaptic vesicles using single section data
Authors: Nikonenko Alexander G. , Skibo Galina G. 
Published: January 2005

AbstractSynaptic vesicles are organelles that specialize in the storage of a neurotransmitter that continuously undergo an exo‐endocytotic cycle. During this cycle vesicles change their positions within a presynaptic terminal and their numbers as well as spatial arrangement can provide insight into a neurotransmitter turnover. This article introduces a technique based on the nearest‐neighbor formalism to quantify the proximity of vesicles to active zones and vesicle clustering in different regions of a terminal. The technique, implemented in a software package, uses the two‐dimensional coordinates of features identified in digitized electron micrographs as an input. It has been validated in the analysis of asymmetric synapses of the rat hippocampal CA1 stratum radiatum affected by transient cerebral ischemia. It was shown that a 15‐minute‐long ischemic episode influenced the spatial arrangement of vesicles that were more distant from active zones and had larger intervesicle spacings with respect to the control. The latter effect was apparently stronger within 200 nm distance of active zones. Microsc. Res. Tech. 65:287–291, 2004. © 2005 Wiley‐Liss, Inc.
Glucose transport by english sparrow (Passer domesticus) skeletal muscle: Have we been chirping up the wrong tree?
Authors: Sweazea Karen L. , Braun Eldon J. 
Published: January 2005

AbstractGlucose uptake by mammalian skeletal muscle has been extensively covered in the literature, whereas the uptake of glucose by avian skeletal muscle has yet to be examined. As skeletal muscle provides the majority of postprandial glucose uptake in mammals, this study was designed to characterize the glucose transport mechanisms and glycogen content of avian skeletal muscle. In addition, plasma glucose levels were measured. English sparrow extensor digitorum communis (EDC) skeletal muscles were used for this study to quantify in vitro radiolabeled‐glucose uptake. Uptake of labeled glucose was shown to decrease in the presence of increasing unlabeled glucose and was maximal by 60 minutes of incubation. Various agents known to increase glucose transport in mammalian tissues, via the insulin and contraction‐responsive pathways, were used to manipulate and characterize in vitro transport in birds. The typical effectors of the mammalian insulin pathway, insulin (2 ng/ml) and insulin‐like growth factor‐1 (48 ng/ml), did not increase skeletal muscle glucose transport. Likewise, inducers of the mammalian contraction‐responsive pathway had no effect on glucose transport by in vitro avian skeletal muscle (5 mM caffeine, 2 mM AICAR (5'–aminoimidazole–4–carboxamide–1–b–D–ribofuranoside). Interestingly, 200µM phloretin, an agent used to block glucose transport proteins, significantly inhibited its uptake (P<0.001). These results suggest that a glucose transporter is responsible for glucose uptake by avian skeletal muscle, albeit at unexpectedly low levels, considering the high plasma glucose concentrations (265.9±53.5 mg/dl) and low skeletal muscle glycogen content (9.1±4.11 nM glucose/mg) of English sparrows. J. Exp. Zool. 303A:143–153, 2005. © 2005 Wiley‐Liss, Inc.
Function of the hepatic melanogenesis in the Newt, Triturus carnifex
Authors: Frangioni Giuliano , Santoni Mario , Bianchi Stefano , Franchi Marco , Fuzzi Giancarlo , Marcaccini Stefano , Varlani Carlo , Borgioli Gianfranco 
Published: January 2005

AbstractLike the majority of lower vertebrates, the newt Triturus carnifex holds varying quantities of melanin and hemosiderin in the Kupffer cells of the liver. Following hypoxic treatment, the amount of these two pigments can increase to such an extent that they can occupy nearly a quarter of the surface of histological sections. A group of six specimens, anesthetised with chlorbutol, were subjected to hypoxic treatment by keeping them in a respiratory chamber containing degassed water under vacuum, with only 1.1 ppm of residual oxygen, until they had consumed the oxygen completely (4 hours, at a temperature of 18°C). Using hematological and histochemical techniques and computerised image analysis, it has been shown that hypoxic animals not only increase the extent of the melanic areas of the liver from about 5–7% to almost 24% compared to control groups kept under two different respiratory conditions (6 anesthetised specimens exposed to the air and 6 submerged in normoxic water), they also went through a remarkable hemolytic process to justify a parallel increase in hemosiderin deposits. Melanin was extracted from the liver by keeping fragments of the organ for one hour at 37°C in an oxidising solution (20 mL of benzyl alcohol, 10 mL of acetone, 5 mL of 10% hydrogen peroxide, and 4 drops of concentrated ammonia solution), then quickly rinsing them in 50% acetone and subsequently letting them stand for 6 hours in 10mL of distilled water alkalised to pH 12 with a drop of ammonia solution. The extract was then left to sediment at pH 2.5 and the black precipitate washed and dried under vacuum. Elemental and spectrophotometric analyses revealed a significant presence of purines in the melanic pigment. This phenomenon can be explained by the animals' need under hypoxic crisis to rapidly neutralise purines resulting from lysis of the nucleated red blood cells by introducing them into an inert molecular complex. A partial model of structure is proposed here. Synthesis of the mixed polymer is possible through the well‐known capacity of ferrous iron to activate tyrosinase (the enzyme responsible for melanogenesis) even in the absence of DOPA. J. Exp. Zool. 303A: 123–131, 2005. © 2005 Wiley‐Liss, Inc.
Mixed reproductive strategy in Tubifex tubifex (Oligochaeta, Tubificidae)?
Authors: Baldo Laura , Ferraguti Marco 
Published: January 2005

AbstractDespite the wide use of the tubificid oligochaete Tubifex tubifex in eco‐toxicological studies, the reproductive strategy adopted by the species, that can reasonably be assumed to be the key to its ecological success, is still not well investigated. This study reports on breeding experiments analysed by allozyme markers (Pgi, Pgm, and Idh), accompanied by a study of the sperm production in the species, with the aim to: (1) clarify the type of uniparental reproduction adopted by the species, (2) test the hypothesis that uniparental reproduction is reversible, (3) investigate the occurrence of biparental reproduction in laboratory cultures. Studies of parent‐offspring comparison at polymorphic allozyme loci showed parthenogenetic reproduction and maintenance of asexuality in the parthenogenetic individuals. A cross‐breeding test performed with couples made up of randomly assorted individuals, whose genotype combinations were suitable for discriminating between sexual and asexual reproduction, failed to show biparental reproduction in laboratory cultures: T. tubifex always reproduced parthenogenetically. Unexpectedly, spermiogenetic analysis indicated that both kinds of sperm produced by the species (eusperm and parasperm) were differentiated in individuals raised either in cohort cultures or in isolation (first, second, and third parthenogenetic generations), with a similar pattern of sperm production correlated to the sexual stage. Interestingly, there was no avoidance of mating in any of the collective cultures analysed. Concomitance between parthenogenetic reproduction and a “normal” male functionality, which is typical of a sexually reproducing species, could be justified by a mixed reproductive strategy or a pseudogamy process occurring in T. tubifex. However, several aspects of the reproductive behaviour of the species deserve further investigation. J. Exp. Zool. 303A:168–177, 2005. © 2005 Wiley‐Liss, Inc.
Organic Crystal Rings Formed in Template Polymer Pores by Evaporation of Solvent
Authors: Yu Xiang , Pan Caiyuan 
Published: January 2005

AbstractSummary: The fabrication of organic crystals into useful forms might play an important role in future electronics technology. A method for fabricating organic crystal rings has been developed. The self‐assembly of six‐armed poly(methyl methacrylate) with a triphenylene core leads to the formation of pores homogeneously distributed in the polymer film. Because the solubility of this polymer in tetrahydrofuran (THF) is lower than that of 2,3,6,7,10,11‐hexamethacrylate triphenylene (HMTP), the holes initially formed and distributed in the polymer film are filled with a THF solution of HMTP. Crystallization nucleation occurs at the edge of holes and HMPT crystals grow at the contact line to form organic crystal rings.Schematic illustration of crystal‐ring formation.imageSchematic illustration of crystal‐ring formation.
Immobilization and Activation of a Single‐Site Chromium Catalyst for Ethylene Polymerization using MgCl2/AlRn(OEt)3 − n Supports
Authors: Severn John R. , Kukalyekar Nileshkumar , Rastogi Sanjay , Chadwick John C. 
Published: January 2005

AbstractSummary: The effective immobilization and activation of a single‐site chromium catalyst for ethylene polymerization has been achieved using MgCl2/AlRn(OEt)3 − n supports, without the use of methylaluminoxane (MAO) or a borate activator. High catalyst activity and a spherical polyethylene‐particle morphology is obtained. Furthermore, the single‐site characteristics of the catalyst are retained, the narrow molecular weight distribution of the polymers obtained are apparent from gel permeation chromatography (GPC) and confirmed by rheological characterization.Shear frequency dependence of the storage modulus of (♦ and ▴) polyethylene ($\overline M _{\rm w} /\overline M _{\rm n}$ = 1.8–1.9) prepared using an immobilized Cr catalyst, compared to (▪) a reference polymer having $\overline M _{\rm w} /\overline M _{\rm n}$ = 4.1.imageShear frequency dependence of the storage modulus of (♦ and ▴) polyethylene ($\overline M _{\rm w} /\overline M _{\rm n}$ = 1.8–1.9) prepared using an immobilized Cr catalyst, compared to (▪) a reference polymer having $\overline M _{\rm w} /\overline M _{\rm n}$ = 4.1.
1H NMR, FT‐IR and MS studies and PM5 semiempirical calculations of complexes between the Schiff base of gossypol with 2‐(aminomethyl)‐15‐crown‐5 and Ca2+, Pb2+ and Ba2+ cations
Authors: Przybylski Piotr , Schroeder Grzegorz , Brzezinski Bogumil , Bartl Franz 
Published: January 2005

AbstractA new Schiff base of gossypol with
2‐(aminomethyl)‐15‐crown‐5 (GSCB) was shown to be capable of complexation with Ca2+, Ba2+ and Pb2+ cations. This process of complex formation was studied by electrospray ionization mass spectrometry, 1H NMR and FT‐IR spectroscopy and by the PM5 semiempirical method. It was found that gossypol Schiff base can form a 1:2 complex with Ca2+, 1:1 or 1:2 complexes with Pb2+ and only a 1:1 complex with Ba2+ cation. In all complexes the Schiff base of gossypol exists as an enamine–enamine tautomer. The cations are coordinated through oxygen atoms from the crown part, lone pairs at the N‐atoms and O‐atoms of the O1H(O1′H) hydroxyl groups. The structures of these complexes were calculated by the PM5 semiempirical method and are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Control of blue mold (Penicillium expansum) by fludioxonil in apples (cv Empire) under controlled atmosphere and cold storage conditions
Authors: Errampalli Deena , Northover John , Skog Lisa , Brubacher Nichole R , Collucci Cheryl A 
Published: January 2005

AbstractA reduced risk fungicide, fludioxonil, was tested for its efficacy against blue mold caused by thiabendazole‐resistant and ‐sensitive Penicillium expansum (Link) Thom in apples under three storage conditions. In a co‐treatment, fludioxonil and inoculum were applied together to test the protective activity of the fungicide on wounds that had been aged for 1 or 2 days. The fungicide was also tested for its curative activity in post‐inoculation treatment on apples that had been inoculated for 1 or 2 days. Fludioxonil was very effective as co‐treatment and as post‐inoculation treatment. At a concentration of 300 mg litre−1, fludioxonil gave complete control of post‐harvest blue mold caused by the thiabendazole‐resistant and ‐sensitive P expansum for 105 days in controlled atmosphere (CA) storage at 2 (±1) °C, for 42 days in common cold storage at 4 (±1) °C and also in a shelf‐life study for 6 days at 20 (±1) °C. Comparison on the effect of fludioxonil in CA storage and common cold storage showed that higher concentrations of fungicide were needed in cold storage than in CA storage. Fludioxonil at a concentration of 450 mg litre−1, gave 98 and 92% control of blue mold of apples in the simulated shelf‐life studies after CA and common cold storages, respectively. Fludioxonil has a potential to be incorporated in the fungicide resistance management strategies for control of blue mold in apples stored for 105 days. Copyright © 2005 Society of Chemical Industry
Development of PPO inhibitor‐resistant cultures and crops
Authors: Li Xianggan , Nicholl David 
Published: January 2005

AbstractRecent progress in the development of protoporphyrinogen oxidase (PPO, Protox)1 inhibitor‐resistant plant cell cultures and crops is reviewed, with emphasis on the molecular and cellular aspects of this topic. PPO herbicide‐resistant maize plants have been reported, along with the isolation of plant PPO genes and the isolation of herbicide‐resistant mutants. At the same time, PPO inhibitor‐resistant rice plants have been developed by expression of the Bacillus subtilis PPO gene via targeting the gene into either chloroplast or cytoplasm. Other attempts to develop PPO herbicide‐resistant plants include conventional tissue culture methods, expression of modified co‐factors of the protoporphyrin IX binding subunit proteins, over‐expression of wild‐type plant PPO gene, and engineering of P‐450 monooxygenases to degrade the PPO inhibitor. Copyright © 2005 Society of Chemical Industry