The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Michael A. Pfaller - One of the best experts on this subject based on the ideXlab platform.
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antifungal susceptibility testing technical advances and potential clinical applications
Clinical Infectious Diseases, 1997Co-Authors: Michael A. Pfaller, Michael G. RinaldiAbstract:: The clinical application of in vitro antifungal susceptibility testing has been limited by a lack of reproducibility and uncertain clinical relevance. As a result of several collaborative studies, the National Committee for Clinical Laboratory Standards (NCCLS) has proposed a standardized antifungal susceptibility test method, NCCLS M27-T. More convenient, user-friendly methods (microdilution broth and stable Gradient Technology) have been evaluated, and the potential for a similar process with a disk diffusion method is apparent. Adaptation of the standard method for susceptibility testing of filamentous fungi appears promising. The existence of a standardized method facilitates meaningful analysis of studies addressing the issue of clinical relevance of antifungal susceptibility testing. Correlation of MICs with clinical response to therapy is beginning to emerge, most notably in relation to fluconazole and itraconazole therapy for oropharyngeal candidiasis associated with infection with the human immunodeficiency virus. This accumulated experience with antifungal susceptibility testing allows us to provide several specific recommendations for antifungal susceptibility testing in the clinical laboratory. Application of this developing Technology to new antifungal agents and other disease states will enhance our ability to effectively deal with the emerging problem of fungal infection.
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Standardization of antifungal susceptibility testing
Journal of Antimicrobial Chemotherapy, 1996Co-Authors: Martin Cormican, Michael A. PfallerAbstract:The application of in-vitro antifungal susceptibility testing to clinical research and to the guidance of antifungal therapy has been limited by a lack of reproducibili ty and uncertain clinical relevance. As a result of studies of the identified variables impacting on in-vitro susceptibility results, the National Committee for Clinical Laboratory Standards have proposed a standardized antifungal susceptibility test method M27-P. The degree of intra- and inter-laboratory reproducibility which can be achieved with this method have been defined in multi-laborat ory collaborative studies. More convenient methods (microdilution broth and stable Gradient Technology) have been evaluated relative to the proposed standard method and the potential for a similar process with a disc diffusion method is apparent. A modification of this standard method for susceptibility testing of filamentous fungi appears promising. The existence of a standardized method and of alternative methods with a defined relationship to the proposed standard, facilitates meaningful analysis of published studies addressing the issue of clinical relevance of antifungal susceptibility testing. As a result of this process, correlation of MICs determined in vitro with clinical response to therapy is beginning to emerge, most notably in relation to fluconazole therapy for oropharyngeal candidosis associated with infection with the human immunodeficiency virus
Martin Cormican - One of the best experts on this subject based on the ideXlab platform.
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Standardization of antifungal susceptibility testing
Journal of Antimicrobial Chemotherapy, 1996Co-Authors: Martin Cormican, Michael A. PfallerAbstract:The application of in-vitro antifungal susceptibility testing to clinical research and to the guidance of antifungal therapy has been limited by a lack of reproducibili ty and uncertain clinical relevance. As a result of studies of the identified variables impacting on in-vitro susceptibility results, the National Committee for Clinical Laboratory Standards have proposed a standardized antifungal susceptibility test method M27-P. The degree of intra- and inter-laboratory reproducibility which can be achieved with this method have been defined in multi-laborat ory collaborative studies. More convenient methods (microdilution broth and stable Gradient Technology) have been evaluated relative to the proposed standard method and the potential for a similar process with a disc diffusion method is apparent. A modification of this standard method for susceptibility testing of filamentous fungi appears promising. The existence of a standardized method and of alternative methods with a defined relationship to the proposed standard, facilitates meaningful analysis of published studies addressing the issue of clinical relevance of antifungal susceptibility testing. As a result of this process, correlation of MICs determined in vitro with clinical response to therapy is beginning to emerge, most notably in relation to fluconazole therapy for oropharyngeal candidosis associated with infection with the human immunodeficiency virus
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Detection of extended-spectrum beta-lactamase (ESBL)-producing strains by the Etest ESBL screen.
Journal of Clinical Microbiology, 1996Co-Authors: Martin Cormican, Steven A. Marshall, R N JonesAbstract:Resistance to contemporary broad-spectrum beta-lactams, mediated by extended-spectrum beta-lactamase (ESBL) enzymes, is an increasing problem worldwide. The Etest (AB Biodisk, Solna, Sweden) ESBL screen uses stable Gradient Technology to evaluate the MIC of ceftazidime alone compared with the MIC of ceftazidime with clavulanic acid (2 micrograms/ml) to facilitate the recognition of strains expressing inhibitable enzymes. In the present study, ESBL-producing strains (17 Escherichia coli transconjugants) were studied to define "sensitive" interpretive criteria for the Etest ESBL screen. These criteria (reduction of the ceftazidime MIC by > 2 log2 dilution steps in the presence of clavulanic acid) defined a group of 92 probable ESBL-positive organisms among the 225 tested strains of Klebsiella species and E. coli having suspicious antibiogram phenotypes. With a subset of 82 clinical strains, the Etest ESBL screen was more sensitive (100%) than the disk approximation test (87%) and was more convenient. The MICs of ciprofloxacin, gentamicin, and tobramycin at which 50% of isolates are inhibited were 16- to 128-fold higher (coresistance) for the ESBL screen-positive group of strains than for the ESBL screen-negative group of strains. Some strains for which cephalosporin MICs were elevated and which were Etest ESBL screen negative were also cefoxitin resistant, i.e., consistent with a chromosomally mediated AmpC resistance phenotype. The Etest ESBL screen test with the ceftazidime substrate appears to be a useful method for detecting or validating the presence of enteric bacilli potentially producing this type of beta-lactamase.
Michael G. Rinaldi - One of the best experts on this subject based on the ideXlab platform.
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antifungal susceptibility testing technical advances and potential clinical applications
Clinical Infectious Diseases, 1997Co-Authors: Michael A. Pfaller, Michael G. RinaldiAbstract:: The clinical application of in vitro antifungal susceptibility testing has been limited by a lack of reproducibility and uncertain clinical relevance. As a result of several collaborative studies, the National Committee for Clinical Laboratory Standards (NCCLS) has proposed a standardized antifungal susceptibility test method, NCCLS M27-T. More convenient, user-friendly methods (microdilution broth and stable Gradient Technology) have been evaluated, and the potential for a similar process with a disk diffusion method is apparent. Adaptation of the standard method for susceptibility testing of filamentous fungi appears promising. The existence of a standardized method facilitates meaningful analysis of studies addressing the issue of clinical relevance of antifungal susceptibility testing. Correlation of MICs with clinical response to therapy is beginning to emerge, most notably in relation to fluconazole and itraconazole therapy for oropharyngeal candidiasis associated with infection with the human immunodeficiency virus. This accumulated experience with antifungal susceptibility testing allows us to provide several specific recommendations for antifungal susceptibility testing in the clinical laboratory. Application of this developing Technology to new antifungal agents and other disease states will enhance our ability to effectively deal with the emerging problem of fungal infection.
Seyed Javad Ahmadi - One of the best experts on this subject based on the ideXlab platform.
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application of ideal temperature Gradient Technology to optimize the chemical exchange and distillation process of boron isotopes separation by ch3 2o bf3 complex
Chemical Engineering and Processing, 2014Co-Authors: Mojtaba Abdollahi, Seyed Javad AhmadiAbstract:Abstract To exert the optimum effect, the chemical exchange process to boron isotope separation was investigated. In this enrichment method the distillation of dimethyl ether-boron trifluoride complex, which was one of the most efficient industrial methods for purification of isotope boron-10, was optimized. In chemical exchange process of boron isotopes separation two chemical reactions occur. The first one is the decomposition reaction that is an endothermic reaction. The second one is the exchange reaction that is a pyrogenic reaction. With increasing temperature, the decomposition reaction is speeded while the exchange reaction is slowed down. Affecting on both decomposition and exchange reactions, the temperature Gradient of column is very important. The separation column is covered by 18 tubular electrical heaters with 350 W power. Each electrical heater is controlled by a separated monitor controller. The monitor controlling system can apply accurate, continuous and various vertical temperature Gradients of distillation column. The highest separation factor for each theoretical stage was determined 1.026 at T bp = 92 °C and ∂ T /∂ Z = 7.56 °C/m. T bp of complex in industrial plant of boron enrichment is 97 °C and the maximum separation factor for a theoretical stage was recorded 1.016 in uncontrolled temperature Gradient of distillation column.
Andrea Cipollina - One of the best experts on this subject based on the ideXlab platform.
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thermolytic reverse electrodialysis heat engine model development integration and performance analysis
Energy Conversion and Management, 2019Co-Authors: Francesco Giacalone, F. Vassallo, Francesca Scargiali, Lyle Griffin, Mariachiara Ferrari, Giorgio Micale, Alessandro Tamburini, Andrea CipollinaAbstract:Abstract Salinity Gradient heat engines represent an innovative and promising way to convert low-grade heat into electricity by employing salinity Gradient Technology in a closed-loop configuration. Among the aqueous solutions which can be used as working fluid, ammonium bicarbonate-water solutions appear very promising due to their capability to decompose at low temperature. In this work, an experimentally validated model for a reverse electrodialysis heat engine fed with ammonium bicarbonate-water solutions was developed. The model consists of two validated sub-models purposely integrated, one for the reverse electrodialysis unit and the other for the stripping/absorption regeneration unit. The impact of using current commercial membranes and future enhanced membranes on the efficiency of the system was evaluated, along with the effect of operating and design parameters through sensitivity analyses. Results indicated that exergy efficiency up to 8.5% may be obtained by considering enhanced future membranes and multi-column regeneration units.
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Salinity Gradient engines
Sustainable Energy from Salinity Gradients, 2016Co-Authors: Alessandro Tamburini, Andrea Cipollina, Michael Papapetrou, Antonio Piacentino, Giorgio MicaleAbstract:Abstract This chapter is devoted to the description of a new class of heat engines based on salinity Gradient Technology and able to convert low-grade heat into power. The salinity Gradient power (SGP) process is employed within a closed loop composed of two different sections: (i) the SGP unit devoted to the energy production, and (ii) a regeneration unit fed by the solutions exiting from the SGP unit and able to restore the initial concentration, thus regenerating the salinity Gradient. The main features, limits and perspectives of this novel heat engine are described along with an overview of the state of the art presented in the literature and an example of exergetic analysis of the cycle. Also, additional information on the availability of the low-grade heat and on the economic evaluation of the produced energy is presented..
