Article View: sci.techniques.microscopy
Article #2Re: A framework for Cytome exploration
From: GTO
Date: Wed, 19 Jan 2005 00:53
Date: Wed, 19 Jan 2005 00:53
229 lines
14626 bytes
14626 bytes
May I inquire if it might be possible to summarize your questions with a slightly shorter expose? I am not familiar with the concept of reviewing entire articles posted as a single newsgroup message. Especially the paragraph about "Copyright notice and disclaimer" appears a little long. No? Maybe I am just missing the point of your inquiry. Gregor "Peter Van Osta" <pvosta_NO_SPAM_@_NO_SPAM_cs.com> wrote in message news:pan.2005.01.18.15.44.33.226234@_NO_SPAM_cs.com... > Hi, > > Besides my on-line version of my article on the Human Cytome Project and > the application of cytomics in medicine and drug discovery I now start an > article on a concept for large scale cytome exploration. It is at this > moment just the beginning > > URL: > http://ourworld.compuserve.com/homepages/pvosta/hcpframe.htm and > http://ourworld.compuserve.com/homepages/pvosta/humcyt.htm > > A framework for cytome exploration > > By Peter Van Osta > Introduction > > Here I want to present and discuss some ideas on the exploration of the > cytome and the conversion of the spatial, spectral and temporal properties > of the cytome and its cells into their in-silico digital representation. > We want to go from physics to quantitative features and finally come to an > interpretation and understanding of the underlying biological process. We > want to extract attributes from the physical process which are giving us > information about the status and development of the process and its > underlying structures. > > First we have to create an in-silico digital representation starting from > the analogue reality captured by an instrument. The second stage (after > creation of an in-silico representation) is to extract meaningful parts > (objects) related to biologically relevant structures and processes. > Thirdly we apply features to the extracted objects, such as area and > (spectral) intensity, which represent (relevant) attributes of the > observed structure and process. Finally we have to separate and cluster > objects based on their feature properties into biologically relevant > subgroups, such as healthy versus disease. > > > > In order to quantify the physical properties of space and time of a > biological sample we must be able to create an appropriate digital > representation of these physical properties in-silico. This digital > representation is then accessible to algorithms for content extraction. > The content or objects of interest are then to be presented to a > quantification engine which associates physical meaningful properties or > features to the extracted objects. These object features build a > multidimensional feature space which can be inserted into feature > analysers to find object/feature clusters, trends, associations and > correlations. Managing the flow > > > > My personal interest is to build a framework in which acquisition, > detection and quantification are designed as modules each using plug-ins > to do the actual work and which operate on objects being transferred > through the framework. Data representing space, time and spectral sampling > are distributed throughout a data management system to be processed. The > focus is not on the individual device to create the data or on individual > algorithms, but on the management of the dataflow through a distributed > system to convert spatial, spectral and temporal data into a feature > (hyper-) space for quantitative analysis. A software framework manages the > flow and transformation of data from physics to features. Up- and > downscaling of cell-based research is dynamically managed by the system as > the scale of processing does not require a change in basic design. I will > mostly focus on imaging technology, but the basic principles should be > applicable on any digitized content extraction process. Images are digital > information matrixes of a higher order; they only become images as such > when we want to look at them. Probing the sample > > When applying digital imaging technology to a biological sample, a clear > understanding of the physical characteristics of the sample and its > interaction with the �?osampling�?� device is a prerequisite for a > successful application of technology. > > The basic principle of a digital imaging system is to create a digital > in-silico representation of the spatial, temporal and spectral physical > process which is being studied. In order to achieve this we try to let > down an equidistant sampling grid on the biological specimen. The physical > layout of this sampling grid in reality is never a precise isomorphic > cubical sampling pattern. The temporal and spectral sampling inner and > outer resolution is determined by the physical characteristics of the > sample (electromagnetic spectral range and spectral sampling layout) and > the interaction with the detection technology being used. > > The instrument which converts the spatial (scale, dimensions), spectral > (electromagnetic energy, wavelength) and temporal continuum of the sample > into its digital representation allows us to take a view on biology beyond > the capacity of our own perceptive system. It rescales space, spectrum and > time into a digital representation accessible to human perception > (contrast-range, colour) and ideally also to quantification. Instruments > rescale spatial dimensions, spectral ranges and time into a scale which is > accessible to the human mind. The digital image acts as a see-through > window on a part of the physical properties of the biological sample, not > on the instrument as such. > > > > We want to insert a probe system into the sample which changes its state > according to the physical characteristics of the sample. The changes in > the probe system are ideally perfectly aligned in a spatial-spectral and > temporal space with the physical properties of the sample itself. Each > probe system senses the state of the specimen with a finite aperture and > so provides us with a view on the biological structure. As such all > sensing is done in XYZ, spectrum and time, it is the inner an outer > resolution of our sampling which changes. When we do 2D imaging, this the > same as 3D with the 3rd dimension collapsed to one layer, but due to the > Depth of Focus (D.O.F.) this represents a physical Z-slice. > > > > In the spectral domain we probe electromagnetic energy along the spectral > axis with a certain inner and outer resolution. We slide up and down the > spectral axis within the limits of one spectral probing system, which > transforms electromagnetic energy. A single CCD camera probes the visible > spectrum in one sweep. A 3CCD camera uses 3 probes to do its spectral > sampling. However increasing or decreasing the density of the spectral > sampling is only a matter of spectral dynamics. We tend to use �?ospectra > imaging�?� for anything which samples the visible spectrum with more than > the spectral resolution of a 3CCD camera. Up-and downscaling our spectral > sampling from broad to narrow, parallel or sequential, continuous or > discontinuous is a matter of applying an appropriate detector array. A > system can manage 1 to n spectral probing devices such as cameras or > PMT�?Ts each sampling a part of the spectrum and spatially aligned allows > to probe the spectrum in a dynamic way. > > > > The time axis is also probed with a varying temporal inner and outer > resolution and depending on the characteristics of the detection device; > the time-slicing can be collapsed or expanded. Time can be sampled > continuously or discontinuously (time-lapse). > > The result is a 5-dimensional system expanding or collapsing each > dimension (XYZ, lambda, time) according to the requirements of > exploration. The device attached to the exploration core, imposes the > inner and outer resolution limits upon the system. In-silico these are > only high-order matrix arrays representing a 5D space. We could call this > a continuously variable in-silico representation. > > The inner an outer resolution of the probing system is determined by the > physical XYZ sampling characteristics of the sampling device, such as its > point spread function (PSF). For a digital microscope the resolving power > of the objective (XYZ) and its depth of view/focus are important issues in > experimental design and determining the application range of a device. The > interaction of the detection device with the image created by the optics > of the system such as Nyquist sampling demands, distribution of spectral > sensitivity, dynamic range, also plays an important role. The pixel or > voxel representation in-silico however is basically �?ounaware�?� of this > meta-information about how the digital density pattern was created. > Detection and quantification algorithms act on the digital information as > such and only the back-translation into physical meaningful data requires > a back-propagation into the real-world layout and dimensions. > > How do we physically organize the sampling of biological specimen? The > exploration of cellular or tissue samples is organised in an > array-pattern, ranging form a single tissue slice on a glass slide up to a > large scale grid of for instance a cell or tissue expression arrays. The > granularity or density of the array pattern is determined by the > experimental demands and upstream and downstream processing capacity. Of > course the optical characteristics of the sample carrier (glass, plastic) > will determine the spatial sampling limits in its inner and outer > resolution. The optical and mechanical characteristics of the device used > to explore the (sub) cellular physical domain will also lead to a spatial, > spectral and temporal application domain. The coarse grid-like pattern of > samples on a sample carrier is being explored at each array position at > the appropriate inner and outer resolution, within the optical physical > boundaries of the device used to capture the data. The outer resolution > barrier of the individual detector in space and time is extended by both > spatial and temporal tiling at a range of intervals. Spectral multiplexing > is being done by using spectral selection devices with the appropriate > spectral characteristics for the spectral profile of the sample. > > The resulting discrete representation of the sampled spatial, spectral and > temporal grid at each array position is being sent to a storage medium to > provide an audit trail for quality assessment and data validation. > > The detection of appropriate objects for further quantification is done > either in-line within the acquisition process or distributed to another > process dealing with the object selection. > > The selected objects are sent to a quantification module which attaches an > array of quantitative descriptors (shape, density �?�) to each object. > Objects belonging to the same biological entity are tagged to allow for a > linked exploration of the feature space created for each individual > object. The resulting data arrays can be fed into analytical tools > appropriate for analysing a high dimensional linked feature space or > feature hyperspace. > > > Copyright notice and disclaimer > > My web pages represent my interests, my opinions and my ideas, not those > of my employer or anyone else. I have created these web pages without any > commercial goal, but solely out of personal and scientific interest. You > may download, display, print and copy, any material at this website, in > unaltered form only, for your personal use or for non-commercial use > within your organization. Should my web pages or portions of my web pages > be used on any Internet or World Wide Web page or informational > presentation, that a link back to my website (and where appropriate back > to the source document) be established. I expect at least a short notice > by email when you copy my web pages, or part of it for your own use. Any > information here is provided in good faith but no warranty can be made for > its accuracy. As this is a work in progress, it is still incomplete and > even inaccurate. Although care has been taken in preparing the information > contained in my web pages, I do not and cannot guarantee the accuracy > thereof. Anyone using the information does so at their own risk and shall > be deemed to indemnify me from any and all injury or damage arising from > such use. To the best of my knowledge, all graphics, text and other > presentations not created by me on my web pages are in the public domain > and freely available from various sources on the Internet or elsewhere > and/or kindly provided by the owner. If you notice something incorrect or > have any questions, send me an email. > > First on-line version published on 9 Jan. 2005, last update on 10 Jan. > 2005 > > Email: pvosta_NOJUNK_@_NOJUNK_cs.com remove the _NOJUNK_ before sending > an email. > > The author of this webpage is Peter Van Osta, MD.
Technical Details
Message-ID:
<HciHd.3294$8Z1.1927@newssvr14.news.prodigy.com>Path:
arc1-ca.pugleaf.net!g2news1.google.com!news4.google.com!newsfeed2.dallas1.level3.net!news.level3.com!newsfeed-00.mathworks.com!newscon06.news.prodigy.com!prodigy.net!newsmst01a.news.prodigy.com!prodigy.com!postmaster.news.prodigy.com!newssvr14.news.prodigy.com.POSTED!481dd867!not-for-mailReferences:
<pan.2005.01.18.15.44.33.226234@_NO_SPAM_cs.com>Show Full Headers
Complete Article Headers
X-Google-Thread: 106237,2d6c5cf3fc9ad6f1 X-Google-Thread: f8e22,2d6c5cf3fc9ad6f1 X-Google-Attributes: gid106237,gidf8e22,public X-Google-Language: ENGLISH,ASCII Path: arc1-ca.pugleaf.net!g2news1.google.com!news4.google.com!newsfeed2.dallas1.level3.net!news.level3.com!newsfeed-00.mathworks.com!newscon06.news.prodigy.com!prodigy.net!newsmst01a.news.prodigy.com!prodigy.com!postmaster.news.prodigy.com!newssvr14.news.prodigy.com.POSTED!481dd867!not-for-mail From: "GTO" <gregor_o@NOSPAMyahoo.com> Newsgroups: sci.techniques.microscopy,bionet.cellbiol References: <pan.2005.01.18.15.44.33.226234@_NO_SPAM_cs.com> Subject: Re: A framework for Cytome exploration Lines: 231 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2900.2180 X-RFC2646: Format=Flowed; Original X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 Message-ID: <HciHd.3294$8Z1.1927@newssvr14.news.prodigy.com> NNTP-Posting-Host: 69.107.106.79 X-Complaints-To: abuse@prodigy.net X-Trace: newssvr14.news.prodigy.com 1106096039 ST000 69.107.106.79 (Tue, 18 Jan 2005 19:53:59 EST) NNTP-Posting-Date: Tue, 18 Jan 2005 19:53:59 EST Organization: SBC http://yahoo.sbc.com X-UserInfo1: FKPO@MC@@S@IRRDY\ZHB^WHAEBZFBL@MAHU^_BAMEH]TCDYG^WHC@EK[WDXJHVKHGFFIZHBL@FX\NIOC@FWYNV\DMNS[HTLIXX\^BUGBXLR@PB@\FKCLXSWAIDFOKG^MFT[GZN^NWY_GVLSRGDYY^AW_MS_RW][KBYZMADO@Y[ABPSPE_TA@LTLFXVTC@RJM Date: Wed, 19 Jan 2005 00:53:59 GMT