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Microdevices enable clinical diagnostics to be miniaturized for use at the point-of-care (POC). Microdevices can be composed of microfilters, microchannels, microarrays, micropumps, microvalves, and microelectronics, and these mechanical and electrical components can be integrated onto chips to analyze and control biological objects at the microscale. The miniaturization of diagnostic tests offers many advantages over centralized laboratory testing, such as small reagent volumes, rapid analysis, small size, low power consumption, parallel analysis, and functional integration of multiple devices. Here, we review work on the development of microdevices to diagnose disease at POC settings.

Biological objects are multiheterogeneous, but at the same time complex and ordered systems. Synergetics is a science that studies processes of self-organization in open dynamic systems. It is based on physical and mathematical methods and seeks to define and generalize laws of emergence and development of organized structures. This approach allows scientists to focus on conditions of lability and mechanisms of emergence and rearrangement of structures.

The results of investigation and development of software and hardware tools for processing images of ring objects under diffusive dissipation are presented. The proposed algorithm was demonstrated to be efficient in endoscopy for measuring the sizes of biological objects. A principal scheme of a hardware system for the implementation of the new method is presented. A plan of clinical testing of the new system is developed.

Rapid prototyping tools exist in many fields of science and engineering, but not as much in biology, especially not general tools that can handle the diversity and complexity of the many spatial and temporal scales in nature. In this paper we introduce and describe a tool that emulates biology and helps to create rapid prototypes of many diverse biological objects. It is anticipated that it can be used to provide support for theories, create “virtual” experiments that would be impossible to undertake or physically measure and emulate in vivo experimentation in a highly cost-effective fashion. An emulation of cancer is also introduced to test the rapid prototyping capability of the Virtual Living Organism (VLO) library. Creating the virtual versions of first chromosomes, then aneuploidy, it became possible to watch the creation of not only benign cancer as expected, but over many test runs the spontaneous emergence of a malignant version. These unexpected results show how building emulations can give insights into biology in theoretical and practical areas.

Texture is a powerful method to describe the appearance of different biological objects in images. The most used texture descriptor is the wellknown Haralick's texture descriptor. We propose a texture descriptor based on random sets. This descriptor gives us more freedom in describing different textures. In this paper we compare the two texture descriptors based on a medical data set. We review the theory of the two texture descriptors and describe the procedure for the comparison of the two methods. A medical data set is used that is derived from colon examination. Decision tree induction is used to learn a classifier model. Cross-validation is used to calculate the error rate. The comparison of the two texture descriptors is based on the error rate, the properties of the two best classification models, the runtime for the feature calculation, the selected features, and the semantic meaning of the texture descriptors.

A convenient mechanism to refer to large biological objects such as sequences, structures and networks is the use of identifiers or handles, commonly called IDs. IDs function as a unique place holder in an application for objects too large to be of immediate use in a table which is retrieved from a secondary archive when needed. Usually, applications use IDs of objects managed by remote databases that the applications do not have any control over such as GenBank, EMBL and UCSC. Unfortunately, IDs are generally not unique and frequently change as the objects they refer to change. Consequently, applications built using such IDs need to adapt by monitoring possible ID migration occurring in databases they do not control, or risk producing inconsistent, or out of date results, or even face loss of functionality. In this paper, we develop a wrapper based approach to recognizing ID migration in secondary databases, mapping obsolete IDs to valid new IDs, and updating databases to restore their intended functionality. We present our technique in detail using an example involving NCBI RefSeq as primary, and OCPAT as secondary databases. Based on the proposed technique, we introduce a new wrapper like tool, called IDChase, to address the ID migration problem in biological databases and as a general platform.

Indirect polysegmental methods of bioimpedance analysis enable to minimize the number of electrodes placed on biological objects with complex geometry (such as human body).However, the borders of investigated regions and their anatomical structure have to be accurately described. For this, the mathematical method of sensivity analysis for various body regions and visualization of their borders using 7-segment BIA analysis with electrode placements at distal zones of the head and extremities is suggested. The model enables to visualize senstivity of various body segments using flat projection of the human body. Graphical examples are shown for the senstivity distribution of impedance parameters in torso, abdominal and aortal regions, as well as in arms, legs, and head. Also, the results of the central blood flow visualization in thoracic region by Kubicek are represented. In general, senstivity analysis can be used as a valuable tool for the substantiating the various diagnostic purposes in polysegmental and whole-body bioimpedance analysis.

In the paper we present the employment of the direction field for contour detection and the segmentation of cylindrical objects, especially an eye iris. We propose a method of calculating the direction field for this kind of objects and present the obtained results. An analysis of the possibility of extending this approach on objects of different kinds is also included.

We have developed a cryo Scanning Transmission X-ray Microscope at the X1A beamline at the NSLS. The system is designed to image hydrated biological objects of a thickness of several micrometers at temperatures of around 110 K at a resolution of ultimately 30 nm or less. A description of the setup of the cryo-STXM is given. We have started to commission the system and present some results, including first images of biological samples.

The boundaries of many biological objects are two-dimensional curves which evolve non-rigidly with time. This paper contains a theory and experiments for estimating motion of such curves using local shape. Beginning from first principles, a symmetric and explicitly non-rigid formulation is developed. The formulation uses the topology of correspondences and its associated geometry.

In this chapter several methods for modelling biological objects are discussed. The methods described in this chapter have the potentiality to serve as morphological models of biological objects. In the first section a model for pattern formation, based on diffusing chemicals, is described. In Sect. 2.2 the iteration processes and fractals which form the general base of the methods described in the Sects. 2.3, 2.4, 2.5 and, 2.6 are discussed. In the last section of this chapter a review is given of the methods mentioned in the chapter and arguments are given as to which method is the most applicable for morphological models of growth processes.

The ability to interact with the environment is an essential feature of living biological systems and corresponds critically to their sensitivity to changes of environmental conditions. The investigation of biological objects and in particular preparation methods have to take into account this genuine lack of rigidity of living biological systems in order to avoid artefacts, i.e. unwanted changes of function or structure. In many cases x-ray microscopy is a well suited tool to investigate supramolecular structures of biological specimens in their natural state.

Homology between biological objects (DNA sequences, species, etc.) can be measured by genetic distance data. A genetic distance may be computed from aligned genetic sequence data; e.g. DNA sequences. We discuss the dot-matrix plot as a possible graphical check of the goodness of the alignment. The assumption of identical distributions along the sequence positions is often inappropriate. Therefore, we discuss aspects of an heuristic which allows the combined exploration of genetic distance between the sequences and of different positional variation. A tree structure is not assumed for such an exploration. Having computed a genetic distance, phylogenetic relations may be analysed by three- and four-objects methods. The approach is illustrated by a set of tRNA sequences.

Microwave influences on biological objects have often been reported in the literature. Most of them were explained on the basis of microwave-induced heating. There are some reports, however, where the microwave-induced heating is so small that a non-thermal mechanism of interaction has to be invoked. Several such mechanisms have been put forward theoretically.1–4 They are based on either high-amplitude molecular vibrations or on spin-flip induced biochemical dynamics.

Two optothermal methods: 1) pulsed photothermal radiometry (PPTR), and 2) the reflection of light from biological objects, for observation of nonequilibrium processes during powerful laser heating are discussed. The results of preliminary experiments with these techniques are presented. The influence of powerful laser irradiation on biotissues can be optimized through feedback, using optothermal techniques as detectors of object states.

Reconstruction of biological objects should, ideally, demonstrate the significance of structures in terms of their dynamic roles in a functional system, such as a cell membrane or a brain. This is the main concern of neuroanatomical illustration, and it is equivalent to graphical modelling in molecular biology. Indeed, three-dimensional manipulation by a computer need not distinguish a molecule from a neuron.

Direct observation of biological structure made possible by electron microscopy has always played an important role in structural research. Modern electron microscopes render biological objects directly visible on the fluorescent screen and in many cases the electron micrographs of the objects are sufficient to support the observations. For example, if the question concerns the determination of the shape of a virus particle, spherical or elongated, the answer can be obtained in a straightforward way. If the details to be derived are small compared to the size of the biological structure a much more elaborate approach will be required. In that case, many electron micrographs have to be recorded and the result will be based on the analysis of many micrographs. In the field of molecular biology, an example is the electron microscopy of nucleic acids, in which the localization of a non base-paired region within a double helical structure has to be mapped.

The discovery of rotating spiral concentrational waves in the B–Z reaction and in some biological objects, such as retina, colonies of microorganisms, cardiac tissue, has provoked a great number of studies of this interesting phenomenon [l]. The problem of structure and properties of such waves in three dimensions remains among the least studied. However, it is of particular interest in the case of myocard because the rotating waves are of the key importance in the genesis of most dangerous heart diseases [2]. Myocard is essentially three-dimensional, the heart wall thickness being comparable with the wavelength.

In this paper, we will describe how electronic speckle pattern interferometry — ESPI — has been used to study and measure the movements of biological objects like the human body both in vitro and in vivo. The main part will deal with work on the human hearing mechanism, in particular recent experiments on vibration analysis of the basilar membrane.

The effects of restricted molecular diffusion in the cavities of various geometrical forma and dimensions with permeable walls on the echo signal amplitude in NMR pulsed field gradient method are studied theoreticalynd experimentaly. The method of the pore size distribution parameter measurements and the method for estimating of permeability of pore materials are proposed. It is shown that pulsed field gradient method permits to find out character of water molecule movement in biomembranes.membranes from the point of water permeability.

Using absorption edges for contrast enhancement or microchemical analysis has been often claimed as one of the main advantages of the soft x-ray microscopy; the K edges of carbon to aluminium and L23 edges of phosphorus to bromine are located in the 0, 8–9 nm wavelength range which is very favourable to image biological objects. But in practice, this opportunity has been very seldom used [26.1]. As a matter of fact, none of the common techniques of x-ray microscopy is really suitable for this purpose.

Medical imaging has long needed a good method of shape description, both to quantitate shape and as a step toward object recognition. Despite this need none of the shape description methods to date have been sufficiently general, natural, and noise-insensitive to be useful. We have developed a method that is automatic and appears to have great hope in describing the shape of biological objects in both 0 and 3D.

Thermal measurements of biological objects are gaining increasing importance in molecular-biological studies (see, e.g., reviews [1–9]. This is due both to recent developments in the field of thermophysical instruments (including scanning differential microcalorimeters [10–18], and to advances in configurational statistics and statistical mechanics of macromolecules, the statistical-thermodynamic theory of phase transitions in biopolymers, and the theory of solutions of macromolecules.

Before initiating quantitative mass determination of biological objects in one’s own laboratory, the following prerequisites must be available: Electron Microscope Any electron microscope is suitable for quantitative work.

The purpose of these remarks is to present a brief description of some techniques of image processing and to offer a few illustrative examples of the ways in which image processing might contribute to studies of red cell shape. Image processing refers to the application of automatic techniques, both digital and analog, to visual images so as to transform the images or to extract quantitative information from them. While it has been known for some time that one can adequately represent a visual image by a mathematical function, it is only within the past 10–15 years that the electronic technology has made it practicable for images to be translated into numerical form and manipulated by computer programs. A number of working groups [8, 9] have already applied image processing to a variety of problems of biological and medical interest; the applications to health science appear to be particularly attractive and numerous, perhaps because so much life science research depends upon visual inspection of biological objects.

The nucleus, both during interphase and mitosis, has come to be regarded as one of the most difficult of biological objects to study by methods of electron microscopy. Apart from the nuclear envelope there are few land marks and little evidence of order such as we find in collagen or muscle. What organization there may be is distributed in depth in the whole nucleus and so defies all but the most painstaking efforts in serial thin sectioning. It is not surprising, therefore, that the problem has proved discouraging except for the most cfetermined and interested investigators. Of these we have a representative few on the program of this symposium and they will give you some measure of the progress that has been made to date. In view of the difficulties, their achievements must be regarded as impressive.

Standardization in fluorometry is still connected with difficulties. The theoretical and practical reasons for this have recently been discussed during the National Bureau of Standards conference in Washington (Conference on Accuracy). In the field of microscope fluorometry standardization is even more difficult because of the tiny volumes and amounts of substances involved and their correlation to microscopic objects to be measured. Previous attempts at the calibration of instruments and standardization of fluorescence intensities were mainly based on, (a) fluorescent glass plates or crystals for calibration of instruments, (b) biological standards such as spermatozoa (Ruch 1961), and (c) microdroplets (Rotman 1966, Rigler 1966, Jongsma et al. 1971) or microspheres. All these attempts claim to produce reproducible fluorescence signals and permit the measured intensities to be correlated with the amounts of fluorescent substances in biological objects.