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1.
Accurate measurement of the biomass and size distribution of picoplankton cells (0.2 to 2.0 microns) is paramount in characterizing their contribution to the oceanic food web and global biogeochemical cycling. Image-analyzed fluorescence microscopy, usually based on video camera technology, allows detailed measurements of individual cells to be taken. The application of an imaging system employing a cooled, slow-scan charge-coupled device (CCD) camera to automated counting and sizing of individual picoplankton cells from natural marine samples is described. A slow-scan CCD-based camera was compared to a video camera and was superior for detecting and sizing very small, dim particles such as fluorochrome-stained bacteria. Several edge detection methods for accurately measuring picoplankton cells were evaluated. Standard fluorescent microspheres and a Sargasso Sea surface water picoplankton population were used in the evaluation. Global thresholding was inappropriate for these samples. Methods used previously in image analysis of nanoplankton cells (2 to 20 microns) also did not work well with the smaller picoplankton cells. A method combining an edge detector and an adaptive edge strength operator worked best for rapidly generating accurate cell sizes. A complete sample analysis of more than 1,000 cells averages about 50 min and yields size, shape, and fluorescence data for each cell. With this system, the entire size range of picoplankton can be counted and measured. 相似文献
2.
Measurement of marine picoplankton cell size by using a cooled, charge-coupled device camera with image-analyzed fluorescence microscopy. 总被引:6,自引:5,他引:1
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Accurate measurement of the biomass and size distribution of picoplankton cells (0.2 to 2.0 microns) is paramount in characterizing their contribution to the oceanic food web and global biogeochemical cycling. Image-analyzed fluorescence microscopy, usually based on video camera technology, allows detailed measurements of individual cells to be taken. The application of an imaging system employing a cooled, slow-scan charge-coupled device (CCD) camera to automated counting and sizing of individual picoplankton cells from natural marine samples is described. A slow-scan CCD-based camera was compared to a video camera and was superior for detecting and sizing very small, dim particles such as fluorochrome-stained bacteria. Several edge detection methods for accurately measuring picoplankton cells were evaluated. Standard fluorescent microspheres and a Sargasso Sea surface water picoplankton population were used in the evaluation. Global thresholding was inappropriate for these samples. Methods used previously in image analysis of nanoplankton cells (2 to 20 microns) also did not work well with the smaller picoplankton cells. A method combining an edge detector and an adaptive edge strength operator worked best for rapidly generating accurate cell sizes. A complete sample analysis of more than 1,000 cells averages about 50 min and yields size, shape, and fluorescence data for each cell. With this system, the entire size range of picoplankton can be counted and measured. 相似文献
3.
The mechanical details of a working model of a proposed small-animal space station which is currently undergoing bench tests are briefly described together with supporting evidence pointing to the feasibility of the program. The one-third cubic meter canister weighs less than 250 kg when loaded for a 9-month period. It would transmit by slow-scan television data concerning mice which it is proposed would be born in the weightless state. Observation of their silhouettes would indicate their growth rates and study of the picture sequence their activity patterns. For example, their use and defense of the feeding and nesting areas and their care of their young.The device would also be used to determine whether the weightless state affected the development of a circadian rhythm or the periodicity of any rhythm that was observed. Recovery of the animals' special living compartment by rendezvous in orbit would permit testing of those born in the device in the earth's gravity field by familiar methods such as those that have been used for the assessment of negative geotactic responses and for the evaluation of rodents living in vertical, as opposed to horizontal mazes.This work was jointly supported by the National Aeronautics and Space Administration, Office of Advanced Research and Technology, and the United States Air Force's Aerospace Medical Division through United States Air Force Contract F29600-67-C-0010. 相似文献
4.
Remote monitoring service for elderly persons is important as the aged populations in most developed countries continue growing. To monitor the safety and health of the elderly population, we propose a novel omni-directional vision sensor based system, which can detect and track object motion, recognize human posture, and analyze human behavior automatically. In this work, we have made the following contributions: (1) we develop a remote safety monitoring system which can provide real-time and automatic health care for the elderly persons and (2) we design a novel motion history or energy images based algorithm for motion object tracking. Our system can accurately and efficiently collect, analyze, and transfer elderly activity information and provide health care in real-time. Experimental results show that our technique can improve the data analysis efficiency by 58.5% for object tracking. Moreover, for the human posture recognition application, the success rate can reach 98.6% on average. 相似文献
5.
《Journal of Biomedical Engineering》1990,12(5):383-388
A microcomputer-based video vector system has been developed to display the resultant ground reaction force vector on a television image of the subject in real-time. For each television field the force platform signals are acquired and processed and the resultant force vector superimposed on the video image of the walking subject. The force platform results are stored on disc and the composite video signals recorded on video tape for further analysis. The system is easy to set up and use and the results can be readily interpreted. The external moments produced at the joint centres by the ground reaction forces can be observed visually and, if required, quantification of the external moments can be achieved following data collection. The spatial resolution of the system is 0.342% vertically and 0.156% horizontally. The force vector visualization technique has routine applications in orthotics and prosthetics. It is also a useful technique for the teaching of biomechanics. 相似文献
6.
Raymond A. Folen Larry C. James Jay E. Earles Frank Andrasik 《Applied psychophysiology and biofeedback》2001,26(3):195-204
Psychophysiological diagnostic and therapeutic methods, to include biofeedback, have been found to be empirically effective in the treatment of a variety of physical disorders. In many areas of the country, however, certified biofeedback practitioners are not well distributed, limiting patient access to this treatment modality. Psychologists at Tripler Army Medical Center have pioneered efforts to develop and provide these needed services via a telehealth venue. Such capability significantly improves access to care, particularly for patient's located at considerable distance from the provider. As the telecommunications infrastructure in rural and remote areas is often quite basic, such a system must be capable of operating within these limited parameters. The system developed by the authors provides real-time video and audio interactivity and allows the therapist to monitor and control biofeedback equipment located at the remote site. The authors discuss the clinical applications, the technology, and relevant practical and ethical issues. 相似文献
7.
Hoglund DH 《Biomedical instrumentation & technology / Association for the Advancement of Medical Instrumentation》2005,(Z1):30-1, 33-4
A standards-based wireless patient monitoring technology can lead to significant improvements in productivity and workflow, provide the potential for reduced errors, and decrease the costs of patient care. A properly implemented wireless patient monitoring system can provide caregivers with increased access to vital patient information at all times. This will help health care institutions build a real-time care process, provide a continuous patient record across the continuum of care, and improve outcomes by creating an environment where clinicians can make evidence-based decisions. 相似文献
8.
We use a 6.8-fs laser as the light source for broad-band femtosecond pump-probe real-time vibrational spectroscopy to investigate both electronic relaxation and vibrational dynamics of the Qy-band of Chl-a at 293 K. More than 25 vibrational modes coupled to the Qy transition are observed. Eleven of them have been clarified predominantly due to the excited state, and six of them are concluded to be nearly exclusively resulting from the ground-state wave-packet motion. Moreover, thanks to the broad-band detection over 5000 cm−1, the modulated signals due to the excited state vibrational coherence are observed on both sides of the 0-0 transition with equal separation. The corresponding nonlinear process has been studied using a three-level model, from which the probe wavelength dependence of the phase of the periodic modulation can be calculated. The probe wavelength dependence of the vibrational amplitude is interpreted in terms of the interaction between the “pump” or “laser,” Stokes, and anti-Stokes field intermediated by the molecular vibrations. In addition, an excited state absorption peak at ∼709 nm has been observed. To the best of our knowledge, this is the first study of broad-band real-time vibrational spectroscopy in Chl-a. 相似文献
9.
I Foche-Perez R Ramirez-Payba G Hirigoyen-Emparanza F Balducci-Gonzalez FJ Simo-Reigadas J Seoane-Pascual J Corral-Peñafiel A Martinez-Fernandez 《Biomedical engineering online》2012,11(1):57
ABSTRACT: BACKGROUND: Acute respiratory infections are the leading cause of childhood mortality. The lack of physicians in rural areas of developing countries makes difficult their correct diagnosis and treatment. The staff of rural health facilities (health-care technicians) may not be qualified to distinguish respiratory diseases by auscultation. For this reason, the goal of this project is the development of a tele-stethoscopy system that allows a physician to receive real-time cardio-respiratory sounds from a remote auscultation, as well as video images showing where the technician is placing the stethoscope on the patient's body. METHODS: A real-time wireless stethoscopy system was designed. The initial requirements were: 1) The system must send audio and video synchronously over IP networks, not requiring an Internet connection; 2) It must preserve the quality of cardiorespiratory sounds, allowing to adapt the binaural pieces and the chestpiece of standard stethoscopes, and; 3) Cardiorespiratory sounds should be recordable at both sides of the communication. In order to verify the diagnostic capacity of the system, a clinical validation with eight specialists has been designed. In a preliminary test, twelve patients have been auscultated by all the physicians using the tele-stethoscopy system, versus a local auscultation using traditional stethoscope. The system must allow listen the cardiac (systolic and diastolic murmurs, gallop sound, arrhythmias) and respiratory (rhonchi, rales and crepitations, wheeze, diminished and bronchial breath sounds, pleural friction rub) sounds. RESULTS: The design, development and initial validation of the real-time wireless tele-stethoscopy system are described in detail. The system was conceived from scratch as open-source, low-cost and designed in such a way that many universities and small local companies in developing countries may manufacture it. Only free open-source software has been used in order to minimize manufacturing costs and look for alliances to support its improvement and adaptation. The microcontroller firmware code, the computer software code and the PCB schematics are available for free download in a subversion repository hosted in SourceForge. CONCLUSIONS: It has been shown that real-time tele-stethoscopy, together with a videoconference system that allows a remote specialist to oversee the auscultation, may be a very helpful tool in rural areas of developing countries. 相似文献
10.
Kinetics of the main phase transition of hydrated lecithin monitored by real-time X-ray diffraction. 总被引:4,自引:4,他引:0
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A method is described for observing and recording in real-time x-ray diffraction from an unoriented hydrated membrane lipid, dipalmitoylphosphatidylcholine (DPPC), through its thermotropic gel/liquid crystal phase transition. Synchrotron radiation from the Cornell High Energy Synchrotron Source (Ithaca, New York) was used as an x-ray source of extremely high brilliance and the dynamic display of the diffraction image was effected using a three-stage image intensifier tube coupled to an external fluorescent screen. The image on the output phosphor was sufficiently intense to be recorded cinematographically and to be displayed on a television monitor using a vidicon camera at 30 frames X s1. These measurements set an upper limit of 2 s on the DPPC gel----liquid crystal phase transition and indicate that the transition is a two-state process. The real-time method couples the power of x-ray diffraction as a structural probe with the ability to follow kinetics of structural changes. The method does not require an exogenous probe, is relatively nonperturbing, and can be used with membranes in a variety of physical states and with unstable samples. The method has the additional advantage over its static measurement counterpart in that it is more likely to detect transiently stable intermediates if present. 相似文献
11.
A 35 mm Robot Royal camera and an electronic flash unit were used at 20–40 m depth in an attempt to identify fish shown on echo-sounder traces. No photographs were obtained. An 8 mm Eumig automatic electric-drive cine camera system was used with daylight at 2–8 m depth to test if the equipment served as a deterrent to the fish. Fish were filmed and their behaviour was unaffected by the presence of the equipment. A simple closed-circuit television system was used with daylight at 0–3 m depth. Low contrast, inherent in the particular equipment, prevented its use at greater depths. Meaningful observations of perch were possible. The use of television camera tubes sensitive to extremely low levels of daylight, and of infra-red sensitive tubes with an infra-red light source is briefly discussed. It is concluded that such systems might help to identify problems of netting technique and assist with observations of fish behaviour. 相似文献
12.
胡坤生 《生物化学与生物物理进展》1994,21(5):421-425
冷却慢扫描电荷耦合器件照相机附在荧光显微镜上组成了一个系统,可把一系列成象进行贮存,通过标记颗粒的位置、强度以及强度分布的差别,在每幅象上可区分500个荧光点.荧光点的运动可以跟踪,通过分析可区分不同的运动方式,在活细胞表面,已观察到受体有直接扩散,随机扩散和局部随机扩散三种运动方式.电荷耦合器件的高灵敏度使观察过程中只产生少量的漂白.现介绍这系统的测量原理和它在生物学上的应用. 相似文献
13.
Objectives To draw on narrative interviews with patients with lung cancer and to explore their perceptions and experience of stigma.Design Qualitative study.Setting United Kingdom.Participants 45 patients with lung cancer recruited through several sources.Results Participants experienced stigma commonly felt by patients with other types of cancer, but, whether they smoked or not, they felt particularly stigmatised because the disease is so strongly associated with smoking. Interaction with family, friends, and doctors was often affected as a result, and many patients, particularly those who had stopped smoking years ago or had never smoked, felt unjustly blamed for their illness. Those who resisted victim blaming maintained that the real culprits were tobacco companies with unscrupulous policies. Some patients concealed their illness, which sometimes had adverse financial consequences or made it hard for them to gain support from other people. Some indicated that newspaper and television reports may have added to the stigma: television advertisements aim to put young people off tobacco, but they usually portray a dreadful death, which may exacerbate fear and anxiety. A few patients were worried that diagnosis, access to care, and research into lung cancer might be adversely affected by the stigma attached to the disease and those who smoke.Conclusion Patients with lung cancer report stigmatisation with far reaching consequences. Efforts to help people to quit smoking are important, but clinical and educational interventions should be presented with care so as not to add to the stigma experienced by patients with lung cancer and other smoking related diseases. 相似文献
14.
Bayesian phylogenetics has gained substantial popularity in the last decade, with most implementations relying on Markov chain Monte Carlo (MCMC). The computational demands of MCMC mean that remote servers are increasingly used. We present Beastiary, a package for real-time and remote inspection of log files generated by MCMC analyses. Beastiary is an easily deployed web-app that can be used to summarize and visualize the output of many popular software packages including BEAST, BEAST2, RevBayes, and MrBayes via a web browser. We describe the design and implementation of Beastiary and some typical use-cases, with a focus on real-time remote monitoring. 相似文献
15.
Non-destructive detection of firefly luciferase (LUC) activity in single plant cells using a cooled, slow-scan CCD camera and an optimized assay 总被引:1,自引:1,他引:0
Benedikt Kost Martin Schnorf Ingo Potrykus Gunther Neuhaus 《The Plant journal : for cell and molecular biology》1995,8(1):155-166
A flexible, comparatively inexpensive system based on a liquid nitrogen-cooled slow-scan CCD (charge coupled device) camera is presented, which can be employed for quantitative low-light (bioluminescence, chemiluminescence or fluorescence) imaging. Using this camera system and the firefly luciferase (LUC) as a screenable marker, transgenic tobacco lines have been produced by direct gene transfer. Bioluminescence emitted from single tobacco cells transiently expressing the firefly luciferase gene (Luc) as well as from stably transformed calli, regenerated shoots, plantlets and T1 seedlings could be monitored in vivo with no effect on the viability of the material analysed. The patterns of light emission from sections through Luc -expressing leaves and bioluminescent single protoplasts isolated from such leaves were also imaged microscopically. The assay used to detect in vivo LUC activity was optimized by quantifying bioluminescence emitted from Luc -expressing tobacco protoplasts and leaves incubated in different substrate solutions and determining the kinetics of light emission during incubation in the substrate solution. 相似文献
16.
Detection of very low light levels arising from individual cells of the naturally bioluminescent bacterium Vibrio fischeri as well as from a luminescence-marked Pseudomonas putida strain was achieved by the aid of two different camera systems. Using a liquid nitrogen-cooled slow-scan CCD (charge-coupled device) camera we were able to detect single-cell bioluminescence within 1 min, and the pictures obtained were of good resolution. In contrast, employing a photon-counting video camera we were able to detect bioluminescent cells within 10 seconds, but at the expense of spatial resolution. This study demonstrates the feasibility of microscopic single cell analysis employing bioluminescence as reporter system. © 1997 John Wiley & Sons, Ltd. 相似文献
17.
BackgroundItapúa is a rural department in Paraguay with a population of about 500,000 and a high degree of agro-mechanization for the production of soybean and other crops. So far, only basic health care is provided. Here we analyzed the cancer mortality in this region as a first step towards epidemiological data for cancer prevention.MethodsWe calculated the age-adjusted mortality rates according to world standard (AMRWs) for the major cancer sites in both males and females between 2003 and 2012, and estimated the differences between the capital and more central districts of Itapúa vs. remote districts.ResultsThere were about 2000 cancer deaths in the decade studied, with AMRWs for all malignancies of 90.9/100,000 in males from central vs. 49.1/100,000 in remote districts and 69.0/100,000 vs. 45.0/100,000 in women. Cancer was mentioned in 12.4% of all death certificates and outweighed mortality from certain infectious and parasitic diseases (3.6%). Cause of death was ill-defined in 19.6% of all death certificates, especially in remote regions and among the elderly. The part of cancer located in the uterus (47.8%) or cell type of neoplasm of the lymphatic or hematopoietic system (73.1%) were often not specified. The uterus (mainly the cervix) (C53–C55) was the leading cancer site in women with AMRWs of 17.2/100,000 in central and 14.0/100,000 in remote districts, followed by the breast. Lung and prostate were the leading cancer sites among men. The lung cancer mortality rate was 19.3/100,000 in the central region but 9.5/100,000 in remote districts. Although children comprised 36% of the population, only 24 death certificates listed cancer as cause of death in this decade.ConclusionsAnalysis of cancer mortality in this rural region of Paraguay, which lacks resources for diagnostics and care, revealed an already large number of cases, with higher rates in the central region than in remote districts. Lung and uterus (primarily the cervix) are common cancer sites and indicate the potential for prevention. However, the quality of the vital statistics needs to be improved. The true cancer burden is most likely underestimated, especially in remote regions and children. 相似文献
18.
A R Turner-Smith 《Journal of biomechanics》1988,21(6):515-529
An optical scanner is described which has been designed primarily for the measurement of human back shape. A projector and television camera were mounted together in a box which could rotate about a horizontal axis. The projector shone a horizontal plane of light, which was viewed at an angle from below by the television camera, linked directly to a minicomputer. The shape of the line of light formed by the plane as it fell on an object, together with a knowledge of the geometry of the system, enabled three-dimensional coordinates of points on the line to be calculated. A record of a surface shape was built up by scanning the object in about 2 s. Calibration of the system was achieved by scanning an object of known dimensions. Sets of algorithms are described which derive geometric parameters from the calibration scan and which sort surface shape coordinates, outline them and detect special markers from the surface shape scan. The accuracy of measurement exceeded the design aim of +/- 3 mm in each axis within a volume of 400 mm x 500 mm x 300 mm. 相似文献
19.
Hyun-Ok Song Je-Hyoung Kim Ho-Sun Ryu Dong-Hoon Lee Sun-Jin Kim Deog-Joong Kim In Bum Suh Du Young Choi Kwang-Ho In Sung-Woo Kim Hyun Park 《PloS one》2012,7(12)
It is clinically important to be able to detect influenza A/H1N1 virus using a fast, portable, and accurate system that has high specificity and sensitivity. To achieve this goal, it is necessary to develop a highly specific primer set that recognizes only influenza A viral genes and a rapid real-time PCR system that can detect even a single copy of the viral gene. In this study, we developed and validated a novel fluidic chip-type real-time PCR (LabChip real-time PCR) system that is sensitive and specific for the detection of influenza A/H1N1, including the pandemic influenza strain A/H1N1 of 2009. This LabChip real-time PCR system has several remarkable features: (1) It allows rapid quantitative analysis, requiring only 15 min to perform 30 cycles of real-time PCR. (2) It is portable, with a weight of only 5.5 kg. (3) The reaction cost is low, since it uses disposable plastic chips. (4) Its high efficiency is equivalent to that of commercially available tube-type real-time PCR systems. The developed disposable LabChip is an economic, heat-transferable, light-transparent, and easy-to-fabricate polymeric chip compared to conventional silicon- or glass-based labchip. In addition, our LabChip has large surface-to-volume ratios in micro channels that are required for overcoming time consumed for temperature control during real-time PCR. The efficiency of the LabChip real-time PCR system was confirmed using novel primer sets specifically targeted to the hemagglutinin (HA) gene of influenza A/H1N1 and clinical specimens. Eighty-five human clinical swab samples were tested using the LabChip real-time PCR. The results demonstrated 100% sensitivity and specificity, showing 72 positive and 13 negative cases. These results were identical to those from a tube-type real-time PCR system. This indicates that the novel LabChip real-time PCR may be an ultra-fast, quantitative, point-of-care-potential diagnostic tool for influenza A/H1N1 with a high sensitivity and specificity. 相似文献
20.
A method for the rapid detection and quantification of Newcastle disease virus (NDV) produced in an animal cell culture-based production system was developed to enhance the speed of the NDV vaccine manufacturing process. A SYBR Green I-based real-time RT-PCR was designed with a conventional, inexpensive RT-PCR kit targeting the F gene of the NDV LaSota strain. The method developed in this study was validated for specificity, accuracy, precision, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The validation results satisfied the predetermined acceptance criteria. The validated method was used to quantify virus samples produced in an animal cell culture-based production system. The method was able to quantify the NDV samples from mid- or late-production phases, but not effective on samples from the early-production phase. For comparison with other quantifiable methods, immunoblotting, plaque assay, and tissue culture infectious dose 50 (TCID50) assay were also performed with the NDV samples. The results demonstrated that the real-time RT-PCR method is suitable for the rapid quantification of virus particles produced in an animal cell-culture-based production system irrespective of viral infectivity. 相似文献