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AccuCount™ 2000 automated colony counter Microscopic Automated Colony Counter

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  • 产品名称:AccuCount™ 2000 automated colony counter Microscopic Automated Colony Counter
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显微自动菌落计数器,AccuCount™ 2000 automated colony counter Microscopic Automated Colony Counter AccuCount 1000 Automated Colony Counter AccuCount 2000 Automated Counter

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AUTOMATED COLONY COUNTERS

| AccuCount | Accessories | How it Works | Applications | Published Papers |

 

Ultrasonic Homogenizer (Sonicator, Cell Disrupter, Sonifier, Sonic Dismembrator, Cell Disruptor)
AccuCount 1000
Automated Colony Counter

Ultrasonic Homogenizer (Sonicator, Cell Disrupter, Sonifier, Sonic Dismembrator, Cell Disruptor)
AccuCount 2000
Automated Counter

 

Many biological procedures depend on an accurate count of the bacterial colonies and other organisms. The enumeration of such colonies is a slow, tedious task. When counts are made by more than one technician, wide variations are often noted. Various attempts have been made to speed up the process and to improve counting precision.

With the development of the BioLogics' AccuCount™ family of counters, significant engineering advancements have been made to provide greater potential for accuracy and precision in a wide range of colony counting applications. Among the technological improvements that have enhanced accuracy and precision are: 1) Significant increase in sensitivity to detect smaller colonies in low contrast media; and 2) more sophisticated and expanded illumination systems to increase the range of visibility and broadens the scope of applications.

To a large extent, accurate colony counting depends on the ability to "see" colonies distinctly, whether viewed by the naked eye or by an automated instrument. Colony morphology is largely a result of the characteristics of the growth media and other environmental conditions. To enhance visibility of colonies and enhance the counting accuracy in an even broader range of applications, it is good practice to employ those procedures that form colonies that are readily discernible by their improved size, shape, distribution and contrast.

Typical Applications

Ames Testing Mouse Lymphoma Assay Bacillus Bacterial Colonies
Bacterial Mutation Assays E. Coli Bacterial Colonies Mammalian Cell Colonies
Salmonella Bacterial Colonies Staphylococcus Bacterial Colonies Plaque Forming Cell Colonies


The AccuCount™ series of automated colony counters are designed to count macroscopic and microscopic objects in a field displaying totals on a highly visible digital readout.

AccuCount™ 1000 

The AccuCount™ 1000 is ideal for the AMES Assayusing 35 to 100 mm petri dishes or 6, 12, and 24 format multi-well dishes. The transmitted illumination can be used whenever analyzing objects on a translucent or transparent background. Transmitted darkfield capability assists in analyzing transparent or low contrast objects. The reflected illumination makes it possible to analyze objects on opaque backgrounds, such as blood and chocolate agar.

The AccuCount's outstanding sensitivity and resolution permits counting of a wide range of object types and sizes, including bacterial colonies, cells, and industrial particles.


AccuCount™ 2000 automated colony counter 
Microscopic Automated Colony Counter
Automated Colony Counter, Colony Counters, Plaque Counter


AccuCount™ 2000 

The AccuCount™ 2000 automated counter is designed to automatically count microscopic objects in a field displaying totals on a highly visible digital readout. Its outstanding sensitivity and resolution permits counting of a wide range of object types and sizes, including bacterial colonies, cells, grains and industrial particles.

The AccuCount™ 2000 is ideal for scoring Unscheduled DNA Synthesis slides and the Mammalian Cell Mutation Assay. The external video camera can be easily interfaced to a wide number of microscopes.


Article No. Title
CLC1001 Evaluation of an Automated Colony Counter
  W. A. GOSS , R. N. MICHAUD, AND M. B. McGRATH
An automated colony counter was found to readily detect surface and subsurface bacterial colonies of 0.3 mm size or greater with a high degree of precision. On a logarithmic scale, counting efficiency consistently ranged from 89 to 95% of corresponding manual count determinations for plates containing up to 1,000 colonies. In routine application, however, automated plate counts up to approximately 400 colonies were selected as a more practical range for operation. The automated counter was easily interfaced with an automated data acquisition system.
 
CLC1002 The Use of Adult Rat Liver Cultures in the Detection of the Genotoxicity of Various Polycyclic Aromatic Hydrocarbons
  C. TONG, M. F. LASPIA, S. TELANG, AND G. M. WILLIAMS
The hepatocyte primary culture (HPC)-DNA repair test and the ***** rat liver epithelial cell (ARL)-hypoxanthine-guanine phosphoribosyl transferase (HGPRT) mutagenesis assay are two in vitro short-term tests that possess intrinsic capability for xenobiotic biotransformation. Both assays detected the genotoxicity of a variety of carcinogenic polycyclic aromatic hydrocarbons. Thus, these two tests, which embody intact cellular metabolism, are useful for the evaluation of this class of carcinogens and provide results that strengthen those obtained in tests dependent upon subcellular metabolism.
 
CLC1003 Health Effects Of Chemicals: V. Computer-Assisted Genetic Toxicology Testing
  LEON S. OTIS, ROSIE Mc CORMICK, AND BETTY STROMNESS
   Until recently manual grain counting took hours for each slide and made routine testing with this procedure impractical. With the new automated system, grains are counted using a "colony counter," which can detect the exposed silver grains using a contrast-discriminator. Grain counting, therefore, can be accomplished in the time it takes to focus the microscope on a cell, set an electronic aperture over the desired counting region (which is displayed on a TV monitor), and push a count button on the colony counter. The data are fed directly into a file in the computer, eliminating the need to record raw data manually. This system has reduced the time required to score 50 cells per slide from a few hours to an average of less than 10 minutes. In addition, all subsequent processing of data is accomplished by computer programs with no additional entry of data required.
 
CLC1004 A Rapid, Semi-Automated Counting Procedure for Enumeration of Antibody-Forming Cells in Gell and Nucleated Cells in Suspension
  DAVID H. KATZ, MERYL FAULKNER, LEE R. KATZ, ERIK LINDH, CHARLES C. LEONHARDT, KIMBERLEY HERR AND AMAR S. TUNG

Since the description by Jerne et al (1) of the hemolysis-in-gel technique for enumerating single antibody-producing cells, this procedure has become one of standard usage in most laboratories engaged in immunological research. Different laboratories use a variety of modifications of the technique, whether in a gel support medium as initially described or the suspension technique described by Cunningham and Szenberg (2). Irrespective of the modification employed, the final analysis involves enumeration of plaques which have developed in the indicator erythrocyte suspension. Typically, this has been done visually by examining either slides or petri dishes with an appropriate light source either with or without the aid of a suitable magnifying lens or stereozoom microscope.
 
CLC1005 Purification and Properties of a Rat Liver Protein that Specifically Inhibits the Proliferation of Nonmalignant Epithelial Cells from Rat Liver
  JAMES B. McMAHON, JAMES G. FARRELLY, AND P. THOMAS IYPE

In inhibitor of cell proliferation was purified from rat liver by alcohol precipitation, ultrafiltration, and DFAE-cellulose chromatography. The hepatic proliferation inhibitor was shown to be pure by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, analytical isoelectric focusing, and high-performance liquid chromatography. The hepatic proliferation inhibitor was found to have a'molecular weight of 26,000 and an isoelectric point of 4.65. This protein inhibited the proliferation of nonmalignant rat liver cells in culture, and removal of the protein reversed the inhibition produced by low doses. It exerted no effect on the proliferation of malignant rat liver cells.
 
CLC1006 Semi-Automated Grain and Cell Counting
  PAUL A. BRUNN JR., SHARON S. FORD, STANLEY E. SHACKNEY

A commercially available bacterial colony counter has been adapted for the counting of radioautographic grains over individual cells in smears, and for counting cells in histologic sections. For the counting of radioautographic grains, the correlation coefficients between counts obtained visually by two observers, and between counts obtained visually and using the instrument were similar (r = .999 and r = .998 respectively). The instrument counts were obtained more rapidly than the visual counts and were associated with less observer fatigue. While performance of the instrument in counting cells in mouse bone marrow sections was less accurate than in counting radioautographic grains, a good estimation of marrow cell number was obtained (r = .968). Data on bone marrow cellularity was obtained far more rapidly than with semi-quantitative methods.
 
CLC1007 Semi-Automated Autoradiographic Measurement of DNA Repair In Normal and Xeroderma Pigmentosum Cultured Human Fibroblasts
  KENNETH H. KRAEMER, JOSEPH K. BUCHANAN, AND SHERMAN F. STINSON

Assessment of DNA repair in cultured human fibroblasts by autoradiography may be facilitated by using semi-automated grain counting instruments. The instrument determined number of autoradiographic grains per nucleus in cultured human skin fibroblasts was found to be linear in comparison to visual counts up to only 30 grains per nucleus. However, with two different instruments a greater range of linearity (100 to 120 grains per nucleus) was attained by measuring the grain surface area per nucleus. Semi-automated analysis of the grain surface area per nucleus yielded measurements of relative rates of unscheduled DNA synthesis after ultraviolet irradiation in xeroderma pigmentosum and normal human fibroblasts, which were reproducible and rapid.
 
CLC1008 From Image to Analysis: Object Detection and Measurement
  MICHAEL K. BENDER

Image Analyzers, both manual and automated, allow users to identify objects and to categorize them using various geometric parameters. Densitometric identification and categorization is also possible with some image analysis equipment. Although image analyzers are not a recent development, many of their applications are new. Technological developments in the last decade have extended the capabilities of image analyzers by increasing speed, accuracy, and flexibility. The instruments have also become significantly more affordable.
 
CLC1009 Detection, Enumeration, and Sizing of Planktonic Bacteria by Image-Analyzed Epifluorescence Microscopy
  MICHAEL E. SIERACKI, PAUL W. JOHNSON, AND JOHN McN. SIEBURTH

Epifluorescence microscopy is now being widely used to characterize planktonic procaryote populations. The tedium and subjectivity of visual enumeration and sizing have been largely alleviated by our use of an image analysis system consisting of a modified Artek 810 image analyzer and an Olympus BHT-F epifluorescence microscope. This system digitizes the video image of autofluorescing or fluorochrome-stained cells in a microscope field. The digitized image can then be stored, edited, and analyzed for total count or individual cell size and shape parameters. Results can be printed as raw data, statistical summaries, or histograms. By using a stain concentration of 5 mg of 4'6-diamidino -2-phenylindole per ml of sample and the optimal sensitivity level and mode, counts by image analysis of natural bacterial populations from a variety of habitats were found to be statistically equal to standard visual counts. Although the time required to prepare slides, focus, and change fields is the same for visual and image analysis methods, the time and effort required for counting is eliminated since image analysis is instantaneous. The system has been satisfactorily tested at sea. Histograms of cell silhouette areas indicate that rapid and accurate estimates of bacterial biovolume and biomass will be possible with this system.
 
CLC1010 Automated Radiographic Grain Counting: Correction for Grain Overlap
  W.H. SCHUETTE, S.S. CHEN, S.J. OCCHIPINTI, H.S. MUJAGIC, AND S.E. SHACKNEY
An algorithm is described for the calculation of radioautographic cell grain count from measurements of total cell nuclear area and total grain area. This algorithm provide-s a statistical correction for grain overlap that is based on the solution to the occupancy problem in probability theory. This method permits the use of automated grain counting over a wide range of grain counts/cell, and extends the useful dynamic range of radioautographic grain counting to well over 200 grains/cell.
Article No. Title
CLC1011 Improvements to the Plaque Assay for Antibody Secreting Cells
  RONALD KISSINGER AND A. DAVID MYL
A capillary glass microslide has been adapted to function as a chamber for the determination of plaque forming cell responses. Comparisons with Cunningham chambers indicate no significant difference between methods. Further, microslides arrive clean and ready to use, thus eliminating the need to assemble chambers as necessitated by the Cunningham method. Used in conjunction with an electronically assisted enumerating device, the microslides provide a rapid and less tedious means for assaying large numbers of animals for PFC responses.
 
CLC1012 Quantification of unscheduled DNA synthesis by a whole cell counting method.
  HILL LE, YOUNT DJ, GARRIOTT ML, TAMURA RN, PROBST GS
  A procedure was developed for the quantification of the autoradiographic assay for unscheduled DNA synthesis. Relative to commonly used practices for grain counting, this procedure provides a more accurate net nuclear grain count by eliminating the subjectivity currently associated with selection of the areas to be counted for the cytoplasmic background count. Briefly, the object area and aperture area modes of an ARTEK 880 colony counter are used to collect values for the total number of silver grains over a particular cell (nuclear and cytoplasmic counts), as well as for the nuclear and cytoplasmic areas. These values are then employed in a short algorithm to determine the net nuclear grain count. This new method provides greater sensitivity for defining weak UDS responses and the data collected readily lends itself to statistical analysis.
 
CLC1013 Limb bud cell culture for in vitro teratogen screening: validation of an improved assessment method using 51 compounds.
  RENAULT JY, MELCION C, CORDIER A
  Rat embryo limb bud cells multiply and undergo chondrogenesis in micromass culture. Teratogenic agents are identified from their inhibition of chondrogenesis, which is quantified by determination of cartilaginous foci number or proteoglycan production. In other in vitro systems, the detection is based on their ability to affect cell proliferation. So far, these methods have failed to distinguish among true inhibition of differentiation, inhibition of cell proliferation, and nonspecific cytotoxicity. The improved technique involves simultaneous measurement of cartilage synthesis and cell multiplication. Differentiation was evaluated by measurement, using an Artek Counter, of nodule areas after Alcian blue staining and proliferation by spectrophotometric quantification of Crystal Violet bound to micromass cells. Using this method, retinoic acid was shown to inhibit chondrogenesis without affecting cell multiplication, whereas 6 aminonicotinamide preferentially inhibited cell multiplication without affecting nodule size. Doxylamine (succinate), a known nonteratogen, induced inhibition of chondrogenesis, but with a parallel inhibition of cell multiplication, reflecting a nonspecific toxic effect. This improvement increases the specificity of the micromass culture test. Validation was performed using 51 compounds. Compounds were classified according to their inhibitory activity and their active concentration. The sensitivity of the test was 61%; the specificity, 100%; and the final accuracy, 75%. The method is fully miniaturised, automated, and computerised, allowing numerous compounds to be rapidly tested at very low cost.
 
CLC1014 Automated autoradiographic grain counting of DNA repair in cultured human fibroblasts after ultraviolet irradiation.
  SATO K, IKENAGA M, YOSHIKAWA K, SANO S. KITAMURA H. KOSAKI G. HAMAOKA T. KONDO S
  Measurement of autoradiographic grains produced by the decay of incorporated radioisotopes is often used for a quantitative assay of the rate of DNA replication and DNA repair in cells or tissues. However, visual grain counting by microscopic observation is time-consuming and tedious process. Recently, Kraemer et al. reported that automated measurement of grains in cultured human cells may be facilitated by using appropriate grain counting instruments. Under their experimental conditions using Kodak NTB-3 emulsion, instrument determined grain number per nucleus was proportional to visual counts up to 30 grains, and then leveled off at much larger visual counts. The saturation phenomenon was due to counting-loss by the instrument caused by overlapping of neighboring grains. To prevent the counting-loss, we have used in the present study Japanese Sakura NR-M2 emulsion which is less sensitive to radiation exposure than Kodak NTB-3, thereby yielding smaller size of grains per radioactive decay. Samples were prepared from cultured skin fibroblasts derived from normal individuals and xeroderma pigmentosum (XP) patients defective in DNA repair. These cells were irradiated with 254 nm UV incubated for 3 h with culture medium containing 3H-thymidine, and autoradiograms were made by dipping in Sakura NR-M2 emulsion. The number of grains as well as grain surface area per nucleus was measured by using ARTEK CYTO TALLY MODEL 900 counting instrument, and compared with visual counts. The results showed that, under our optimum condition, the instrument-determined number of grains was directly proportional to visual counts, at least up to 150 grains per nucleus, with a correlation coefficient of 0.971.
 
CLC1015 Detection, enumeration, and sizing of planktonic bacteria by image analyzed epifluorescence microscopy.
  SIERACKI ME, JOHNSON PW, SIEBURTH JM
  Epifluorescence microscopy is now being widely used to characterize planktonic procaryote populations. The tedium and subjectivity of visual enumeration and sizing have been largely alleviated by our use of an image analysis system consisting of a modified ARTEK 810 image analyzer and an Olympus BHT-F epifluorescence microscope. This system digitizes the video image of autofluorescing or fluorochrome-stained cells in a microscope field. The digitized image can then be stored, edited, and analyzed for total count or individual cell size and shape parameters. Results can be printed as raw data, statistical summaries, or histograms. By using a stain concentration of 5 micrograms of 4'6-diamidino-2-phenylindole per ml of sample and the optimal sensitivity level and mode, counts by image analysis of natural bacterial populations from a variety of habitats were found to be statistically equal to standard visual counts. Although the time required to prepare slides, focus, and change fields is the same for visual and image analysis methods, the time and effort required for counting is eliminated since image analysis is instantaneous. The system has been satisfactorily tested at sea. Histograms of cell silhouette areas indicate that rapid and accurate estimates of bacterial biovolume and biomass will be possible with this system.
 
CLC1016 An in situ procedure for accurately detecting mutations using mammalian cells.
  CATTANACH PI, RIACH CG, MITCHELL A, WILLINGTON SE, ZAJAC WC, COMBES RD, CASPARY WJ
  Previously an in situ protocol to accurately measure mutation rates at the tk locus using l5178y mouse lymphoma cells has been described (genetics 126:435, '90). Rather than allowing cells to express the mutant Phenotype in liquid suspension, the cells were segregated and Immobilized for expression in semi solid medium. This procedure permitted a more accurate recovery of slowly growing mutants. Using the in situ method, spontaneous mutation rates 50 fold higher than those obtained in liquid suspension were observed. We now report the results of investigating the effects of medium composition (rpmi with 10% horse serum versus fischer's with 10% horse serum for growth and 20% for cloning), time of trifluorothymidine (tft) addition for mutant selection, and manual versus automatic colony counting on the yield of spontaneous tft resistant colonies as part of validating the assay in another laboratory. Under all conditions, the maximum number of mutant colonies that could be counted occurred at 48 hrs. Thereafter, the numbers counted declined, presumably because of nutrient depletion. Mutation frequencies (mf) were consistently slightly higher with rpmi medium (376 x 10( 6)) as compared with fischer's (345 x 10(6)). Irrespective of medium used, higher me values were obtained by manual counting at 48 and 60 hrs compared with enumeration using an ARTEK 880 colony counter. Manual counting was backed up where necessary by microscopic examination.
 
CLC1017 Evaluation of the potential of o-nitroaniline to induced unscheduled DNA synthesis in primary rat hepatocyte cultures with cover memo & sheet.
  SRI INTERNATIONAL, INC.
   The effects of ortho-nitroaniline were examined in the rat hepatocyte primary culture repair assay. Based on preliminary cytotoxicity tests o-nitroaniline was tested at concentrations of 0.1, 0.5, ], 5, 10, 50, 75, and 100 microgram/ml in one assay and at concentrations of 5, 10, 50 and 75 microliter/ml in a second assay. The net grain counts measured on autoradiographs by an ARTEK Model 830 or 980 colony counter were negative at each concentration of the test article and the solvent control while the positive control (2-acetylaminofluorene) produced a strong positive response.
 
CLC1018 Alternatives to the Use of Live Vertebrates in Biomedical Research and Testing: Second Annual Annotated Bibliography
  GEORGE J. COSMIDES, DEPUTY DIRECTOR, TOXICOLOGY INFORMATION PROGRAM, NATIONAL LIBRARY OF MEDICINE, NATIONAL INSTITUTES OF HEALTH, BETHESDA, MARYLAND ROBERT S. STAFFORD, INFORMATION ANALYST, OAK RIDGE NATIONAL LABORATORY, OAK RIDGE, TENNESSEE PO-YUNG LU, DIRECTOR, CHEMICAL HAZARD EVALUATION PROGRAM, OAK RIDGE NATIONAL LABORATORY, OAK RIDGE, TENNESSEE
Because of considerable interest from Congress, the National Institutes of Health (NIH), and the public about animal welfare and alternatives to animal testing, the National Library of Medicine (NLM) searches its online databases and prepares quarterly annotated bibliographies on alternative or in vitro methods for toxicity testing and biomedical research. The objective is to present current literature organized as citations with brief annotations for easy scanning. The Institute of Laboratory Animal Resources (ILAR) has invited NLM to publish in ILAR News this annual supplement, which is an edited, concatenated version of the quarterly bibliographies. The ILAR News Editorial Panel and outside reviewers edit and condense the quarterly bibliographies so the entries are appropriate for the ILAR News audience. The scientific community is concerned about humane animal care and is sensitive to public concerns about how and why animals are used in biomedical research and toxicity testing. The following events reflect the involvement of the public and the U.S. government in this issue: an array of federal legislation related to animal welfare and the use of laboratory animals, U.S. Public Health Service policy on the humane care and use of laboratory animals, and efforts at NIH to promote and support a search for alternative methods to the use of animals in biomedical research and testing. Scientists generally view the use of laboratory animals in biomedical research and toxicity testing as necessary except where valid scientific alternative methods will satisfy all testing requirements. Howevex, when animals must be used, the scientific community supports careful consideration of the number of animals used and encourages reductions when they are scientifically feasible.
 
CLC1019 Antiestrogenicity of environmental polycyclic aromatic hydrocarbons in human breast cancer cells
  KATHLEEN F. ARCARO A,B,*, PATRICK W. O'KEEFE A,B, YI YANG B, WILLIAM CLAYTON B, JOHN F. GIERTHY A,B
The total concentration of 14 polycyclic aromatic hydrocarbons (PAHs) was determined to be 3400-fold greater in a sediment sample from an industrial site on the St. Lawrence River (SLR), NY, than in a sediment sample from a non-industrial site on the Kinderhook Creek (KC), NY. PAH fractions from extracts of the two environmental samples and two reconstituted mixtures as well as the 14 individual PAHs were examined for their toxic, estrogenic, and antiestrogenic activities using MCF-7 focus, recombinant human estrogen receptor (ER) binding, whole-cell ER binding, and 17b-estradiol (E2) metabolism assays. PAH fractions from the KC and SLR were antiestrogenic; they significantly inhibited the formation of foci elicited in MCF-7 breast cancer cells by 1 nM E2. Eight of the 14 individual PAHs, and the reconstituted mixtures were also antiestrogenic. Results from the whole-cell ER binding assay and the radiometric analysis of E2 metabolism indicate that the PAHs detected in the KC and the SLR environmental samples induce antiestrogenic responses in metabolically intact human breast cancer cells through at least two mechanisms: one involving competition for the ER by a PAH metabolite and the other involving depletion of E2 through induction of metabolism. Published by Elsevier Science Ireland Ltd.t
 
CLC1020 BIOAVAILABILITY OF GENOTOXIC MIXTURES IN SOIL
  N. BORDELON, K. WASHBURN, L.-Y. HE, AND K.C. DONNELLY*, DEPARTMENT OF VETERINARY ANATOMY AND PUBLIC HEALTH, TEXAS A&M UNIVERSITY, COLLEGE STATION, TX, 77843-4458
Contaminated media at Superfund sites typically consist of complex mixtures of organic and inorganic chemicals which are difficult to characterize, both analytically and toxicologically. The current EPA approach to risk assessment uses solvent extraction to remove chemicals from the soil as a basis for estimating risk to the human population. However, contaminants that can be recovered with a solvent extract may not represent the mixture of chemicals that are available for human exposure. A procedure using an aqueous extraction was investigated to provide a more realistic estimate of what chemicals are bioavailable. A study was conducted with two soil types: creosote-contaminated sandy soil and coal tar-contaminated clay soil spiked with benzo(a)pyrene [B(a)P], and trinitrotoluene (TNT). Samples were extracted with hexane:acetone and water titrated to pH2 and pH7. HPLC analysis demonstrated up to 35% and 29% recovery of contaminants using the aqueous extracts. The estimated cancer risk for the aqueous extract was one order of magnitude less than that for solvent extracts. Analysis using the Salmonella/microsome assay demonstrated that solvent extracts were genotoxic (133 revertants/mg) with metabolic activation while aqueous extracts of clay soil were not genotoxic. Sandy soil showed genotoxicity both with and without metabolic activation. These results suggest that solvent extraction techniques may overestimate the concentration of contaminants that are available for human exposure and, hence, the risk associated with the presence of the contaminants in soil.


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