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Counting Method (counting + method)
Selected AbstractsUrban Textural Analysis from Remote Sensor Data: Lacunarity Measurements Based on the Differential Box Counting MethodGEOGRAPHICAL ANALYSIS, Issue 4 2006Soe W. Myint Lacunarity is related to the spatial distribution of gap or hole sizes. For low lacunarity, all gap sizes are the same and geometric objects are deemed homogeneous; conversely, for high lacunarity, gap sizes are variable and objects are therefore heterogeneous. Textures that are homogeneous at small scales can be quite heterogeneous at large scales and vice versa, and hence, lacunarity can be considered a scale-dependent measure of heterogeneity or texture. In this article, we use a lacunarity method based on a differential box counting approach to identify urban land-use and land-cover classes from satellite sensor data. Our methodology focuses on two different gliding box methods to compute lacunarity values and demonstrate a mirror extension approach for a local moving window. The extension approach overcomes, or at least minimizes, the boundary problem. The results from our study suggest that the overlapping box approach is more effective than the skipping box approach, but that there is no significant difference between window sizes. Our work represents a contribution to not only advances in textural and spatial metrics as used in remote-sensing pattern interpretation but also for broadening understanding of the computational geometry of nonlinear shape models of which lacunarity is the reciprocal of fractal theory. [source] A fatigue criterion for general multiaxial loadingFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 1 2000Jiang An incremental fatigue damage model is proposed. The model incorporates the critical plane concept in multiaxial fatigue, plastic strain energy and material memory in cyclic plasticity. With an incremental form the model does not require a cycle counting method for variable amplitude loading. The model is designed to consider mean stress and loading sequence effects. Features of the new model are discussed and the determination of material constants is detailed. Verification of the model is achieved by comparing the predictions obtained by using the new model and experimental data of four materials under different loading conditions. [source] Snorkelling as a method for assessing spawning stock of Atlantic salmon, Salmo salarFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2007P. ORELL Abstract, Reliability of underwater snorkel counts of adult Atlantic salmon, Salmo salar L., was analysed in the tributaries of the River Teno, close to the spawning period. In small (width 5,20 m) rivers, the replicated total counts of salmon were reasonably precise (CV = 5.4,8.5%), while in the medium-sized river (width 20,40 m) the precision of the counting method was considerably lower (CV = 15.3%). Low precision in a medium sized river was also observed in an experiment using marked live fish where the observation efficiency varied between 36.4% and 70.0%. In a small river, the detection efficiency of artificial fish silhouettes (test salmon) was almost perfect in pools (98%), but decreased in rapids (84%). Separate counts of males, females, grilse and large salmon were usually more variable than total counts, indicating that divers were more capable of locating a fish than properly identifying its sex and sea-age. The behaviour of adult salmon was favourable to conduct snorkel counts, as fish normally stayed still, or after hesitating, moved upstream (>95%of the cases) when encountering a diver. The high observation efficiency (>90%) and precision, favourable behaviour of salmon and congruence between snorkel counts and catch statistics in small rivers suggest that reliable data on Atlantic salmon spawning stock can be collected by snorkeling provided that the environmental conditions are suitable and the divers are experienced. [source] Do arthropod assemblages display globally consistent responses to intensified agricultural land use and management?GLOBAL ECOLOGY, Issue 5 2008S. J. Attwood ABSTRACT Aim, To determine whether arthropod richness and abundance for combined taxa, feeding guilds and broad taxonomic groups respond in a globally consistent manner to a range of agricultural land-use and management intensification scenarios. Location, Mixed land-use agricultural landscapes, globally. Methods, We performed a series of meta-analyses using arthropod richness and abundance data derived from the published literature. Richness and abundance were compared among land uses that commonly occur in agricultural landscapes and that represent a gradient of increasing intensification. These included land-use comparisons, such as wooded native vegetation compared with improved pasture, and a management comparison, reduced-input cropping compared with conventional cropping. Data were analysed using three different meta-analytical techniques, including a simple vote counting method and a formal fixed-effects/random-effects meta-analysis. Results, Arthropod richness was significantly higher in areas of less intensive land use. The decline in arthropod richness was greater between native vegetation and agricultural land uses than among different agricultural land uses. These patterns were evident for all taxa combined, predators and decomposers, but not herbivorous taxa. Overall, arthropod abundance was greater in native vegetation than in agricultural lands and under reduced-input cropping compared with conventional cropping. Again, this trend was largely mirrored by predators and decomposers, but not herbivores. Main conclusions, The greater arthropod richness found in native vegetation relative to agricultural land types indicates that in production landscapes still containing considerable native vegetation, retention of that vegetation may well be the most effective method of conserving arthropod biodiversity. Conversely, in highly intensified agricultural landscapes with little remaining native vegetation, the employment of reduced-input crop management and the provision of relatively low-intensity agricultural land uses, such as pasture, may prove effective in maintaining arthropod diversity, and potentially in promoting functionally important groups such as predators and decomposers. [source] Antibacterial effects of MDPB against anaerobes associated with endodontic infectionsINTERNATIONAL ENDODONTIC JOURNAL, Issue 8 2010N. Izutani Izutani N, Imazato S, Noiri Y, Ebisu S. Antibacterial effects of MDPB against anaerobes associated with endodontic infections. International Endodontic Journal. Abstract Aim, To investigate the antibacterial effects of 12-methacryloyloxydodecylpyridinium bromide (MDPB), an antibacterial monomer synthesized by combining quaternary ammonium with a methacryloyl group, against three anaerobes associated with endodontic infections using planktonic and biofilm cells. Methodology, The antibacterial activity of unpolymerized MDPB against Enterococcus faecalis, Fusobacterium nucleatum and Prevotella nigrescens was examined by agar-disc diffusion tests and determination of the minimum inhibitory/bactericidal concentrations (MIC/MBC). Rapid killing effects of MDPB against three bacteria in planktonic form were examined by a cell number counting method, and those against biofilm cells were assessed by a viability staining method. Results, MDPB demonstrated inhibition against all of the bacteria tested by agar-disc diffusion tests. The MIC/MBC values of MDPB for the three anaerobes were much smaller than those of other resin monomers, although greater compared with those of cetylpyridinium chloride or chlorhexidine diacetate for E. faecalis and F. nucleatum. Significant reduction in viable planktonic cells was obtained by contact with 250 ,g mL,1 of MDPB for 20 s (P < 0.05, Fisher's PLSD tests), and 40 s contact with 500 ,g mL,1 or 20 s contact with 1000 ,g mL,1 of MDPB resulted in more than 90% killing. Biofilm cells of all species were completely killed by application of 1000 ,g mL,1 of MDPB for 60 s. Conclusion, MDPB was found to have strong antibacterial effects against E. faecalis, F. nucleatum and P. nigrescens, and such effects were rapidly exhibited even against biofilm cells, suggesting the usefulness of application of MDPB to resin-based materials for root canal filling. [source] Dementia, cognitive impairment and mortality in persons aged 65 and over living in the community: a systematic review of the literatureINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2001Michael E. Dewey Abstract Background No recent attempt has been made to synthesise information on mortality and dementia despite the theoretical and practical interest in the topic. Our objective was to estimate the influence on mortality of cognitive impairment and dementia. Methods Data sources were Medline, Embase, personal files and colleagues' records. Studies were considered if they included a majority of persons aged 65 and over at baseline either drawn from a total community sample or drawn from a random sample from the community. Samples from health care facilities were excluded. The search located 68 community studies. Effect sizes were extracted from the studies and if they were not included in the published studies, effect sizes were calculated where possible: this was possible for 23 studies of cognitive impairment and 32 of dementia. No attempt was made to contact authors for missing data. Results For the studies of cognitive impairment Fisher's method (a vote counting method), gave a p -value (from eight studies) of 0.00001. For studies of dementia, age-adjusted confidence intervals (CI) were pooled (odds ratio (OR) 2.63 with 95% CI 2.17 to 3.21 from six studies). Conclusions Levels of cognitive impairment commonly found in community studies give rise to an increased risk of mortality, and this appears to be true even for quite mild levels of impairment. The analysis confirms the increased risk of mortality for dementia, but reveals a dearth of information on the causes of the excess mortality and on possible effect modification by age, dementia subtype or other variables. Copyright © 2001 John Wiley & Sons, Ltd. [source] Application of a microfluidic device for counting of bacteriaLETTERS IN APPLIED MICROBIOLOGY, Issue 3 2006K.-I. Inatomi Abstract Aims:, To develop a miniaturized analytical system for counting of bacteria. Methods and Results:,Escherichia coli cells were used throughout the experiments. The system consists of a microfluidic chamber, a fluorescence microscope with a charge-coupled device (CCD) camera and syringe pumps. The chamber was made of a silicone rubber (30 × 30 mm and 4 mm high). The E. coli cells were flowed from a micro-nozzle fabricated in the chamber and detected with the CCD camera. The individual cells were indicated as signal peaks on a computer. The cell counts showed a good correlation compared with that of a conventional plate counting method, and results of the simultaneous detection of live and dead cells were also presented. Conclusions, Significance and Impact of the Study:, The system having a small disposable nozzle has the advantages for low cost and safe medical or environmental analysis, when compared with a conventional flow cytometer. This is the first step of the development of a one-chip microbe analyzer. [source] Compliance of the bladder neck supporting structures: Importance of activity pattern of levator ani muscle and content of elastic fibers of endopelvic fasciaNEUROUROLOGY AND URODYNAMICS, Issue 4 2003Matija Barbi Abstract Aims Firm bladder neck support during cough, suggested to be needed for effective abdominal pressure transmission to the urethra, might depend on activity of the levator ani muscle and elasticity of endopelvic fascia. Methods The study group of 32 patients with stress urinary incontinence and hypermobile bladder neck, but without genitourinary prolapse, were compared with the control group of 28 continent women with stable bladder neck. The height of the bladder neck (HBN) and compliance of the bladder neck support (C) were assessed, the latter by the quotient of the bladder neck mobility during cough and the change in abdominal pressure. By using wire electrodes, the integrated full-wave rectified electromyographic (EMGave) signal of the levator ani muscle was recorded simultaneously with urethral and bladder pressures. The pressure transmission ratio (PTR), time interval between the onset of muscle activation and bladder pressure increment (,T), and area under the EMGave curve during cough (EMGcough) were calculated. From bioptic samples of endopelvic fascia connecting the vaginal wall and levator ani muscle, elastic fiber content was assessed by point counting method. Mann-Whitney test was used to compare all the variables. Correlations between the parameters were evaluated by using the Spearman correlation coefficient. Results In the study group, HBN was significantly lower (P,<,0.001), C was significantly greater (P,<,0.001), and PTR was significantly lower (P,<,0.001). In the study group, the muscular activation started later (median, ,Tl, ,0.147 second; ,Tr, ,0.150 second), and in the control group, it preceded (,Tl, 0.025 second; P,<,0.001; ,Tr, 0.050 second; P,<,0.001) the bladder pressure increment. EMGcough on the left side was significantly greater in the study group (P,<,0.046). Elastic fiber content showed no difference between the groups. The analysis of all patients revealed negative correlations between C and PTR (r,=,,0.546; P,<,0.001) and between C and ,Tl (r,=,,0.316; P,<,0.018). Conclusions Firm bladder neck support enables effective pressure transmission. Timely activation of the levator ani seems to be an important feature. Neurourol. Urodynam. 22:269,276, 2003. © 2003 Wiley-Liss, Inc. [source] Spontaneous platelet aggregation in Kawasaki disease using the particle counting methodPEDIATRICS INTERNATIONAL, Issue 6 2003Masashi Taki AbstractBackground:,Platelet aggregation is generally measured by the optical density method. This method is not very sensitive in detecting platelet activation because of the poor correlation between the formation of platelet aggregates and light transmission, and inability to detect small platelet aggregates. Recently, a new method was developed that detects small platelet aggregates formed in the early phase of platelet aggregation by means of a particle counting technique using light scattering. Methods:,The present study used the particle counting method to measure spontaneous platelet aggregation (SPA) produced by agitation with a stirrer bar without agonists in patients with Kawasaki disease (KD) and children's thrombotic disease, and compared the results with the conventional optical density method. Results:,Using the particle counting method, significantly higher SPA rates were found before treatment than in healthy adults and at the other stages of treatment. A similar tendency was noted with the optical density method; however, the positive rate of SPA was significantly higher with the particle counting method in each stage except the second stage, which was the period from the start of gamma-globulin therapy to 20 days. Conclusion:,These results indicate that enhanced platelet aggregation is noted at a high frequency before treatment of KD and that the particle counting method is superior to the optical density method in detecting enhanced platelet aggregation. [source] Antiproliferative effects of different plant parts of Panax notoginseng on SW480 human colorectal cancer cellsPHYTOTHERAPY RESEARCH, Issue 1 2009Chong-Zhi Wang Abstract The chemical constituents and antiproliferative effects on SW480 human colorectal cancer cells of different plant parts of P. notoginseng were evaluated. The contents of saponins in extracts from root, rhizome, flower and berry of P. notoginseng were determined using high performance liquid chromatography. The contents and proportions of saponins were different among the four plant parts. Using the cell counting method, the antiproliferative effects were evaluated and the results indicated all four extracts, at 0.05,1.0 mg/mL, showed concentration-related antiproliferative effects on the cancer cells. The flower extract had stronger effects compared with the other three extracts; at 1.0 mg/mL, it inhibited the cell growth by 93.1% (p < 0.01). The antiproliferative effects of major saponins in notoginseng, notoginsenoside R1, ginsenosides Rb1, Rb3 and Rg1, were also evaluated, and the observed effects of major constituents support the pharmacological activities of extracts. The effects of notoginseng extracts on cell cycle and apoptosis of SW480 cells were determined using flow cytometry. Notoginseng extract can arrest the cells in S and G2/M phases. Remarkably apoptosis induction activities of notoginseng extracts were observed with the flower extract possessing the most potent effect, supporting the antiproliferative effect. Copyright © 2008 John Wiley & Sons, Ltd. [source] High Numbers of Naked Amoebae in the Planktonic Waters of a Mangrove Stand in Southern Florida, USATHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 3 2000ANDREW ROGERSON ABSTRACT. This is the first study to examine the abundance of naked amoebae in the water column of a mangrove stand. A total of 37 different morphotypes was noted and at least 13 of these are probably new species. Over a one-year sampling interval, amoebae averaged 35,400 cells liter,1 (range 2,000,104,000) by an indirect enrichment cultivation method. Densities in the upper end of this range arc the highest ever reported for any planktonic habitat. Variation between samples was related to the quantity of suspended aggregates (floes) in the water column emphasizing that amoebae are usually floc-associated. The study also showed that it is essential to disrupt floc material prior to withdrawing sample aliquots for the indirect counting method since several amoebae can occupy the interstices of aggregates. There is concern that indirect enumeration methods that require organisms to be cultured in the laboratory seriously underestimate the true count. A direct counting method using acridine orange staining and epifluorescence microscopy was attempted to assess the possible magnitude of the error associated with indirect counting. While this direct method had limitations, notably the difficulty of unambiguously differentiating between small amoebae and nanoflagellates, the results suggested that the indirect method gave estimates that were close to the true count (within a factor of two). Mangrove waters are rich in heterotrophic protozoa (,3 × 106 liter1) and while the heterotrophic flagellates are by far the dominant group, naked amoebae outnumber ciliates some 20-foid. The ecological consequences of high numbers of amoebae, particularly the common small forms less than 10 ,m in length, need to be examined for these important coastal sites. [source] 4332: Determination of corneal endothelial cell density in French eye banks: second lookACTA OPHTHALMOLOGICA, Issue 2010N DELESALLE Purpose Considering the importance of having a precise, robust and especially reproducible ECD counting method, Afssaps organized from April 2008 to June 2009 a second assessment of the reliability of the routine cell count within the 18 french Eye banks. Methods The study design was similar to the first assessment driven by the laboratory ,Biology, engineering and imaging of Corneal Graft' in 2003 (Transplantation 2004; 78: 1299-1302).5 test corneas (1 mm2 of flat mounted, fixed and alizarin stained human corneal endothelium) were selected and sent to the 18 Eye banks. All the usual technicians of each bank had to count the test corneas using the routine method(s) employed to assess grafts. Results 430 counts were carried out by 70 eye banks technicians, by manual and/or image analysis system. 42% (180/430) deviated by more than 10% from the expected ECD. Among them, 128 were over-estimated (max +88%) and 52 were under-estimated (max -31%). 2 banks constantly over-estimated (in the mean +31,7% and +42,7%, no calibration and/or material problem) but the 16 other banks were in average within ±13% from expected ECDs. For manual methods, a statistically significant difference between banks was observed for the 5 test corneas, whereas no difference was observed with image analyzers. ECD obtained with the analysers were closer to expected values than with the manual methods. Compared to the 2003 study, reliability of ECD determination globally improved. Conclusion Image analysis systems prove more reliable (precise and with a lower intra and inter observer variability) than manual counting methods. This ,second look' of Eye banks will allow editing recommendations to improve ECD determination. [source] Blood basophil numbers in chronic ordinary urticaria and healthy controls: diurnal variation, influence of loratadine and prednisolone and relationship to disease activityCLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2003C. E. H. Grattan Summary Background The basopenia of chronic urticaria relates to histamine releasing autoantibodies in the serum of patients with autoimmune urticaria. This reduction in circulating basophils may be due to active recruitment into weals. If so, it might be expected that numbers in blood would be reduced when urticaria is active and increased after treatment. The primary aim of this study was to look at diurnal variation of basophil numbers in patients with chronic ordinary urticaria (not physical or vasculitic) in relation to disease activity and the effect of treatment with antihistamines and corticosteroids, and to compare the results with healthy controls. A secondary aim was to compare a standard manual counting method with automated basophil counts and to look at numbers of other circulating leucocytes that might be relevant to urticaria pathogenesis. Methods Manual basophil counts using a toluidine blue stain and automated 5-part differentials (Coulter® Gen. SÔ) were performed at 4-hourly intervals from 08.00 to 20.00 in 10 healthy controls (six women, age 24 to 63 years) and seven chronic urticaria patients (five women, 24 to 50 years). All chronic urticaria patients had severe daily or almost daily urticaria. Only one of six chronic urticaria sera showed in vitro basophil histamine releasing activity. Counts were performed without treatment, after a week of taking loratadine 10 mg daily and after 3 days of adding prednisolone at 0.6 mg/kg/day (maximum 40 mg). Daily urticarial activity scores (UAS) were derived from weal numbers and itch, maximum 7. Results There was no significant overall diurnal variation of basophil numbers in healthy controls or chronic urticaria patients. Mean (SE) manually counted basophil were higher in healthy controls than chronic urticaria (43.4/µL (2.1) vs. 4.4 (0.8), P < 0.001). Basophil counts were reduced in healthy controls on steroids (19.2 (1.9), P < 0.001) but increased in chronic urticaria (8.9 (1.9), P < 0.001). Loratadine did not influence them. UAS fell on treatment (3.3 (0.4) baseline, 1.4 (0.5) on loratadine and 0.5 (0.2) on prednisolone with loratadine, P < 0.001). There was a negative linear correlation between basophil numbers and UAS in untreated chronic urticaria patients (P = 0.001, Spearman rank correlation). Manual and automated basophil counts showed poor agreement. Lymphocyte numbers were lower in chronic urticaria than healthy controls. Neutrophils increased whereas lymphocytes and eosinophils decreased in all subjects on prednisolone. They were unaffected by loratadine. Conclusion The results are consistent with the hypothesis that circulating basophils may be recruited from blood into urticarial weals during disease activity. Automated counts are not suitable for assessing basophil numbers in chronic urticaria. The relevance of reduced lymphocyte numbers in chronic urticaria needs to be explored. [source] | |||||||||||||