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Prise en charge du spondylolisthesis par lyse isthmique a niamey, a propos de 20 cas
S Sanoussi, M Bawa, S Rabiou, M Boureima
African Journal of Neurological Sciences , 2008,
Abstract: Objectif Evaluer la prise en charge chirurgicale du spondylolisthésis par lyse isthmique à Niamey. Méthode Etude prospective en série continue réalisée dans le service de Neurochirurgie de Niamey de Janvier 1999 à Janvier 2006. Etaient inclus les spondylolisthésis par lyse isthmique. Les spondylolisthésis étaient classés selon la classification de Meyerding. L’indication opératoire était retenue après échec du traitement conservateur sur les radiculalgies. L’évaluation clinique préopératoire et post opératoire était basée sur la cotation fonctionnelle de Beaujon. Le traitement comprenait une décompression radiculaire associée à une ostéosynthèse par montage rigide et court. Résultats Il s’agissait de 11 hommes et 09 femmes. La moyenne d’age était de 27,231ans avec des extrêmes de 17ans et de 40 ans; les radiculalgies évoluaient depuis 1,01 ans en moyenne .La radiculalgie était systématisée dans 65% des cas. Sur le plan radiologique, 10 patients étaient au stade I selon Meyerdig, 7 au stade II et 3 au stade III. La lyse isthmique était sur L5 bilatérale chez 17cas patients (85% des cas), sur L4 dans 3 cas (15%). Le score moyen préopératoire était de 9.1/20 ; à 3 mois du postopératoire, il était évalué à 14.8 sur 20. Conclusion Après échec du traitement conservateur, l’indication opératoire basée sur la radiculalgie donne des résultats satisfaisants.
Widespread Disulfide Bonding in Proteins from Thermophilic Archaea  [PDF]
Julien Jorda,Todd O. Yeates
Archaea , 2011, DOI: 10.1155/2011/409156
Abstract: Disulfide bonds are generally not used to stabilize proteins in the cytosolic compartments of bacteria or eukaryotic cells, owing to the chemically reducing nature of those environments. In contrast, certain thermophilic archaea use disulfide bonding as a major mechanism for protein stabilization. Here, we provide a current survey of completely sequenced genomes, applying computational methods to estimate the use of disulfide bonding across the Archaea. Microbes belonging to the Crenarchaeal branch, which are essentially all hyperthermophilic, are universally rich in disulfide bonding while lesser degrees of disulfide bonding are found among the thermophilic Euryarchaea, excluding those that are methanogenic. The results help clarify which parts of the archaeal lineage are likely to yield more examples and additional specific data on protein disulfide bonding, as increasing genomic sequencing efforts are brought to bear. 1. Introduction The archaea inhabit incredibly diverse environments [1]. Many species thrive at temperatures exceeding 100°C. Growth at such high temperatures presents special challenges, among the most serious being the problem of stabilizing cellular proteins in their natively folded configurations. For many proteins, the folded configuration is only modestly favored energetically compared to the unfolded state [2], and high temperatures irreversibly unfold the vast majority of proteins derived from organisms that live at moderate temperatures. The question of how thermophilic proteins are stabilized has therefore attracted considerable attention over the years [3, 4]. Numerous studies have concluded that thermophilic proteins are stabilized by a wide array of forces and effects, which appear to present themselves to different degrees in different proteins and organisms [3, 5–8]. Increased atomic packing [9, 10], hydrophobic interactions [11], ionic interactions [9, 12–14], and shorter loops [15] have all been noted as providing additional noncovalent stabilization in thermophilic proteins. More unexpected was the realization that disulfide bonding—a much stronger, covalent force—might play an important role in some organisms [16, 17]. A striking clue came when the structure of the enzyme adenylosuccinate lyase from the hyperthermophilic Pyrobaculum aerophilum revealed that the six cysteines in the protein chain pair up to form three disulfide bonds [17]. This prompted the development by Mallick et al. [16] of genomic calculations, which supported the idea that some thermophiles use disulfide bonding as a major mechanism for protein
Totius en sy universiteit  [cached]
V. E. d ’Assonville
Koers : Bulletin for Christian Scholarship , 1977, DOI: 10.4102/koers.v42i3.1209
Abstract: As die digter S.J. Pretorius in 1950, ’n jaar voor die selfstandig- wording van die Potchefstroomse Universiteit vir Christelike Ho r Onderwys, ’n ,,Alma-Mater”-lied dig^), dan maak hy ’n kostelike historiese greep as hy die ontstaan van die Universiteit vertolk met die aanhef Gebore uit die nag van smaad” . Hierdie nag van smaad” word op sy donkerste as die Tweede Vryheids- oorlog die Teologiese Skool van Burgersdorp feitlik tot stilstand bring en die twee Boererepublieke ’n puinhoop gemaak word. Dan bevind J.D . du Toit, die Kaapse rebel, hom teen die einde van 1900 saam met ander Kapenaars in ballingskap in Amsterdam waar hy aan die Vrye Universiteit van Abraham Kuyper diep onder die indruk kom van die idee van ’n Christelike Universiteit en die Christelike wetenskap.
The impact of mesophilic and thermophilic anaerobic digestion on biogas production  [PDF]
P. Vindis,B. Mursec,M. Janzekovic,F. Cus
Journal of Achievements in Materials and Manufacturing Engineering , 2009,
Abstract: Purpose: of this paper is to compare mesophilic and thermophilic anaerobic digestion of three maize varieties. Parameters such as biogas production and biogas composition from maize silage were measured and calculated. The amount of biogas production (methane) was observed by the mini digester.Design/methodology/approach: Biogas production and composition in mesophilic (35 degrees C) and thermophilic (55 degrees C) conditions were measured and compared. The measurements were performed with mini digester according to DIN 38414 part 8. We used three different maize varieties (NK PAKO, PR34N43 and RAXXIA).Findings: Biogas yields ranged between 315 - 409 Nl kg VS-1 in mesophilic conditions and 494 – 611 Nl kg VS-1 in thermophilic conditions. The highest biogas yield was in case of NK PAKO (611 NI kg VS-1) in thermophilic conditions. The lowest biogas yield was in case of PR34N43 (315 NI kg VS-1) in mesophilic conditions. Biogas quality produced in thermophilic temperature range is better than biogas quality produced in mesophilic temperature range. Thermophilic digestion is 4 times more intense, has higher VSS removal efficiency and yields more biogas.Research limitations/implications: Thermophilic stabilization of energy plants at 55°C is truly economical, more biogas is produced. The only disadvantage of thermophilic stabilization is that more energy is used for heating fermenters. Therefore, further researches are necessary.Practical implications: For biogas plants with mesophilic digesters we suggest an upgrade of existing mesophilic digesters (35°C) to thermophilic digesters (55°C), which is an economically beneficial solution compared to construction of additional mesophilic digesters.Originality/value: The mini digester for biogas production was built as special equipment. It can be used in mesophilic and thermophilic conditions. The quality of the produced biogas is determined with a gas analyser GA 45.
Thermophilic Bateria
嗜热细菌

Wei Jun,Cai Miaoying Institute of Microbiology,Academia Sinica,Beijing,
卫军
,蔡妙英

生物多样性 , 1993,
Abstract: Thermophiles have been of interest for a long time both to scientists and to the general public, and are believed to have a great potential in biotechnology and some products are already on the markets. For present the current status of research, here we collect a great deal of new information on the thermophilic (eu)bacteria, discuss the main properties and differences of thermophilic bacteria and archaea, The diveristy, ecology, and evolution of thermophiles are also briefly reviewed.
Resensie: "Pik Botha en sy tyd"
C Villet
Tydskrif vir letterkunde , 2012,
Abstract: Pik Botha en sy tyd. Theresa Papenfus. Hatfield, Pretoria: Litera Publikasies, 2011. 991 pp. ISBN: 978-1- 920188-33-7.
Gamma-H2AX biodosimetry for use in large scale radiation incidents: comparison of a rapid lyse/fix protocol with a routine method  [PDF]
Jayne Moquet,Stephen G R Barnard,Kai Rothkamm
PeerJ , 2015, DOI: 10.7287/peerj.preprints.163v1
Abstract: Following a radiation incident, preliminary dose estimates made by γ-H2AX foci analysis can supplement the early triage of casualties based on clinical symptoms. Sample processing time is important when many individuals need to be rapidly assessed. A protocol was therefore developed for high sample throughput that requires less than 0.1 ml blood, thus enabling finger prick sampling. The technique combines red blood cell lysis and leukocyte fixation in one step on a 96 well plate, in contrast to the routine protocol, where lymphocytes are separated by Ficoll density gradient centrifugation with subsequent washing and fixation steps. The rapid lyse/fix method reduced the estimated sample processing time for 96 samples to about 4 h compared to 15 h using the routine protocol. However, scoring 20 cells in 96 samples prepared by the rapid protocol took longer than for the routine method (3.1 versus 1.5 h at zero dose; 7.0 versus 6.1 h for irradiated samples). Similar foci yields were scored for both protocols and reliable dose estimates were obtained for coded samples, with mean absolute differences from the actual doses of 0.26 and 0.27 Gy for the routine and lyse/fix method, respectively. The lyse/fix protocol can therefore facilitate high throughput processing for γ-H2AX biodosimetry for use in large scale radiation incidents, at the cost of somewhat longer foci scoring times.
Widespread Disulfide Bonding in Proteins from Thermophilic Archaea  [PDF]
Julien Jorda,Todd O. Yeates
Archaea , 2011, DOI: 10.1155/2011/409156
Abstract: Disulfide bonds are generally not used to stabilize proteins in the cytosolic compartments of bacteria or eukaryotic cells, owing to the chemically reducing nature of those environments. In contrast, certain thermophilic archaea use disulfide bonding as a major mechanism for protein stabilization. Here, we provide a current survey of completely sequenced genomes, applying computational methods to estimate the use of disulfide bonding across the Archaea. Microbes belonging to the Crenarchaeal branch, which are essentially all hyperthermophilic, are universally rich in disulfide bonding while lesser degrees of disulfide bonding are found among the thermophilic Euryarchaea, excluding those that are methanogenic. The results help clarify which parts of the archaeal lineage are likely to yield more examples and additional specific data on protein disulfide bonding, as increasing genomic sequencing efforts are brought to bear.
Investigation of the Effect of Heating, Vesicular Arbuscular Mycorrhiza and Thermophilic Fungus on Cotton Wilt Disease
L. Naraghi,H. Zareh-Maivan,A. Heydari,H. Afshari-Azad
Pakistan Journal of Biological Sciences , 2007,
Abstract: In this study, combinations of spores of a thermophilic fungus (Talaromyces flavus), Vesicular Arbuscular Mycorrhiza (VAM) and microsclerotia of Verticillium dahliae under various temperature treatment (31-38°C) in triplicate trial, were investigated and results were compared with those of non-treated controls. Five cotton seeds were planted in each pot containing 3 kg of pasteurized soil. In each pot, combinations of 4x103 VAM spores, 2.5x10 9 spores of thermophilic fungus (T. flavus ) and 5x105 microsclerotia of V. dahliae were added. Symptoms of Verticillium wilt were observed after 45 days. Index of disease severity was measured. Results indicated that pre-heating of microsclerotia at 31 and 35°C for 10 and 14 h, respectively, caused a 15% reduction in leaf infection index. Presence of VAM and thermophilic fungus (T. flavus) spores caused 23 and 50% reductions in the disease development , respectively. Concurrent presence of mycorrhiza and thermophilic fungus spores caused a 10-20% reduction in disease development. These findings provide a promising approach to the control of Verticillium wilt of cotton. However, heat treatment of soil may prove difficult. Further studies in this regard are required and useful agricultural practices such as seasonal heating may be applied in the cotton fields.
Extremely thermophilic microorganisms and their polymer-hidrolytic enzymes
Andrade, Carolina M.M.C.;Pereira Jr., Nei;Antranikian, Garo;
Revista de Microbiologia , 1999, DOI: 10.1590/S0001-37141999000400001
Abstract: thermophilic and hyperthermophilic microorganisms are found as normal inhabitants of continental and submarine volcanic areas, geothermally heated sea-sediments and hydrothermal vents and thus are considered extremophiles. several present or potential applications of extremophilic enzymes are reviewed, especially polymer-hydrolysing enzymes, such as amylolytic and hemicellulolytic enzymes. the purpose of this review is to present the range of morphological and metabolic features among those microorganisms growing from 70oc to 100°c and to indicate potential opportunities for useful applications derived from these features.
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