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Using carbon nanotubes for sensing the mass in a biosensor is recently proven as an emerging technology in healthcare industry. This study investigates relative frequency shifts and sensitivity studies of various biological objects such as insulin hormone, immunoglobulin G (IgG), the most abundant type of antibody, and low-density lipoproteins (LDL) masses using the single-wall carbon nanotubes as a biomass sensor via continuum mechanics. Uniform distributed mass is applied to the single-wall carbon nanotube mass sensor. In this study, fixed-free and fixed-fixed type single-wall carbon nanotubes with various lengths of relative frequency shifts are studied. Additionally, the sensitivity analysis of fixed-free and fixed-fixed type CNT biological mass sensors is carried out. Moreover, mode shapes studies are performed. The sensitivity results show better, if the length of the single-wall carbon nanotube is reduced.

Ways of making precise magnetic measurements and the corresponding magnetometric equipment are promising for practical use in studying electromagnetic processes that occur in biological objects. Analysis of the magnetic component of the electromagnetic activity of different human organs using superconducting quantum magnetometers can be used to develop new medical technologies for the early diagnosis and effective treatment of cardiovascular, oncological, and other major diseases.

Stereology is the method of choice for the quantitative assessment of biological objects in microscopy. It takes into account the fact that, in traditional microscopy such as conventional light and transmission electron microscopy, although one has to rely on measurements on nearly two-dimensional sections from fixed and embedded tissue samples, the quantitative data obtained by these measurements should characterize the real three-dimensional properties of the biological objects and not just their “flatland” appearance on the sections. Thus, three-dimensionality is a built-in property of stereological sampling and measurement tools. Stereology is, therefore, perfectly suited to be combined with 3D imaging techniques which cover a wide range of complementary sample sizes and resolutions, e.g. micro-computed tomography, confocal microscopy and volume electron microscopy. Here, we review those stereological principles that are of particular relevance for 3D imaging and provide an overview of applications of 3D imaging-based stereology to the lung in health and disease. The symbiosis of stereology and 3D imaging thus provides the unique opportunity for unbiased and comprehensive quantitative characterization of the three-dimensional architecture of the lung from macro to nano scale.

Atomic absorption spectrometry (AAS) is one of the most widely used and available methods for analysis of substances and materials. It allows one to determine about 70 elements from the periodic table and is characterized by rapidity, high accuracy and sensitivity, as well as simplicity of analytical techniques. A feature of AAS is simultaneous determination of only one element due to the use of a measurement design with a line source (hollow-cathode lamps, high-frequency electrodeless lamps, optical quantum generators, etc.). To make AAS more competitive, the first commercially available continuum source atomic absorption spectrometer was designed in 2004. Unique analytical capabilities of the new instruments found application first of all in the analysis of food, pharmaceuticals, waste and drinking water, oil and petrochemicals, biological objects, etc. This review covers publications on the application of continuum source AAS in analytical chemistry and provides a development outlook of the method.

Subject and Purpose. Synthesis of biological sorbents has become one of the ways to solve the problem of environment contamination with heavy metals. Today, studying properties of biosorbents with injection of magnetic nanoparticles is important. Thus, injection of magnetic nanoparticles of magnetite (Fe3O4) improves absorption properties of biosorbents. The subject of the present work is magnetic resonance properties of nanoparticles inside biosorbents, such as macromycetes like Pleurotus ostreatus. The purpose is to examine these magnetic resonance properties and analyze the state of magnetite nanoparticles inside Pleurotus ostreatus. Methods and Methodology. The X-band Electron Spin Resonance (ESR) method is employed to register ferromagnetic resonance (FMR) spectra at T = 294 K. TEM-images of magnetic nanoparticles are made in the transmission electron microscope. Mathematical modeling for the properties of the arising clusters of magnetic Fe3O4 nanoparticles inside macromycetes Pleurotus ostreatus is performed using a phenomenological model upon the well-known Kittel equation. A model enhancement is proposed in the case of interacting nanoparticles inside an ellipsoidal magnetic cluster. Results. It has been shown that Fe3O4 nanoparticles are well absorbed by macromycetes and gather into structural clusters regardless of the concentration of magnetic nanoparticles injected. These magnetic clusters of magnetic nanoparticles have ellipsoidal shapes with an aspect ratio of 3:1:1. The developed mathematical model makes it possible to obtain dimensions of magnetic clusters from the FMR spectra and evaluate their shape and mutual magnetic interaction. The mathematical modeling results are in good agreement with TEM-images of these clusters inside Pleurotus ostreatus. As a result of modeling are in good agreement with the TEM-images of these clusters inside Pleurotus ostreatus. Conclusion. The presented results will contribute to the development of non-destructive testing of the state of biological sorbents using magnetic resonance radio spectroscopy methods.

To substantiate the quantitative values of the process of destruction of weeds by means of electric impulse and to elucidate the mechanism of damage and the sequence of disturbances that occur in the internal structure of the processed plants, it is necessary to know not only the design of the electrical circuit of the plant tissue substitution but also to have information on the nature of the change in the parameters of the elements of this scheme during electric damage. The presented technique allows (with the help of inexpensive and accessible technical means) to control the damage to the tissues of a weed plant and to calculate quantitative values using developed mathematical apparatus. The analysis shows that the damage to weed plant tissues can be characterized, first of all, by the loss of cell membranes in their semipermeable functions and an increase in the active conductivity of the processed areas of plants. Such changes in the internal structure of plant tissue lead to loss of cell viability in the areas subjected to the electric impulse treatment. The presented analysis fits the current thinking of biophysicists on the electrical damage to the internal structure of biological objects. The technological studies of the process of the electric impulse irreversible damage to plant tissues conducted, based on the analysis presented in the article, allow us to limit the supplied electric energy that makes it possible to make electric impulse weeding an energy-saving means of combating weeds.

The biological activity of laser radiation (wavelength, 632.8 nm) when it interacts with human serum albumin is demonstrated. The most noticeable effect of exposure to laser radiation is observed when the energy density is 28.8 J cm−2. It is assumed that three-photon absorption is the main mechanism of biological stimulation.

Detection systems with deferred registration of luminescence signals are promising for performing complex tasks of imaging of biological objects due to their simplicity and low cost. In the present work, β‑NaYF4:Tm3+Yb3+/NaYF4 nanocrystals with anti-Stokes photoluminescence have been used in deferred registration systems. It has been shown that there is a significant time delay between the exciting laser pulse and luminescence signal, which makes it possible to use this class of nanoparticles in the creation of wide-field imaging systems with deferred registration. The possibility of using nanoparticles for detecting a photoluminescence signal in the second transparency window of biotissue has been demonstrated. This system can be based on the resonance excitation and detection of the photoluminescence signal of Yb3+ ions.

Classification of methods and means of laser polarimetry of biological tissues (liquids) is described, methods and means of imaging mueller-matrix polarimetry for reproduction of anisotropic characteristics of biological layers are analyzed. According to the results of the analysis factors of possible increase of reliability of diagnostics of pathological changes of biological objects in application of polarization technologies are determined.

This article discusses the possibility of applying the principles of Fourier polarimetry to the study of optically anisotropic networks of biological objects. The possibility of using statistical analysis to study the coordinate distributions of polarization states in the Fourier plane, the field of scattered laser radiation by virtual polycrystalline networks is demonstrated. The polarization-inhomogeneous structure of the Fourier transform of laser images of ensembles of optical-anisotropic biproenescent crystals has been revealed.

Purpose: Extension of the method of surface plasmon resonance spectroscopy to the case of polarized laser radiation.

The article describes the basics of microwave diagnostics from the point of view of creating a new method for obtaining data to detect pathologies in biological objects, as well as sensors and computational human phantoms for preliminary modeling of experimental equipment.

Light can be employed as a tool to alter and manipulate matter in many ways. An example has been the implementation of optical trapping, the so called optical tweezers, in which light can hold and move small objects with 3D control. Of interest for the Life Sciences and Biotechnology is the fact that biological objects in the size range from tens of nanometers to hundreds of microns can be precisely manipulated through this technology. In particular, it has been shown possible to optically trap and move genetic material (DNA and chromatin) using optical tweezers. Also, these biological entities can be severed, rearranged and reconstructed by the combined use of laser scissors and optical tweezers. In this review, the background, current state and future possibilities of optical tweezers and laser scissors to manipulate, rearrange and alter genetic material (DNA, chromatin and chromosomes) will be presented. Sources of undesirable effects by the optical procedure and measures to avoid them will be discussed. In addition, first tentative approaches at cellular-level genetic and organelle surgery, in which genetic material or DNA-carrying organelles are extracted out or introduced into cells, will be presented., Spanish Nuclear Security Council (CSN-UAM15112018).

Plenoptic cameras use arrays of micro-lenses to capture multiple views of the same scene in a single compound image. They enable refocusing on different planes and depth estimation. However, until now, all types of plenoptic computational imaging have been limited to visible light. We demonstrate an x-ray plenoptic microscope that uses a concentrating micro-capillary array instead of a micro-lens array and can simultaneously acquire from one hundred to one thousand x-ray projections of imaged volumes that are located in the focal spot region of the micro-capillary array. Hence, tomographic slices at various depths near the focal plane can be reconstructed in a way similar to tomosynthesis, but from a single x-ray exposure. The microscope enables depth-resolved imaging of small subvolumes in large samples and can be used for imaging of weakly absorbing artificial and biological objects by means of propagation phase-contrast., Comment: The following article has been accepted by Applied Physics Letters

Advances in laser and optoelectronic technologies have brought the general concept of optomechanical manipulation to the level of standard biophysical tools, paving the way towards controlled experiments and measurements of tiny mechanical forces. Recent developments in direct laser writing (DLW) have enabled the realization of new types of micron-scale optomechanical tools, capable of performing designated functions. Here we further develop the concept of DLW-fabricated optomechanically-driven tools and demonstrate full-3D manipulation capabilities over biological objects. In particular, we resolved the long-standing problem of out-of-plane rotation in a pure liquid, which was demonstrated on a living cell, clamped between a pair of forks, designed for efficient manipulation with holographic optical tweezers. The demonstrated concept paves the way for the realization of flexible tools for performing on-demand functions over biological objects, such as cell tomography and surgery to name just few.

The optoacoustic effect leading to excitation of acoustic waves upon absorption of a variable light flux is considered. This effect is of interest from the viewpoint of practical application in biomedical measurements as a promising noninvasive method for diagnostics of biological objects. The results of experimental flow diagnostics based on laser excitation of an optoacoustic signal in liquid are presented. An algorithm of the flow cytometry procedure is developed.

The study of biological objects using a light microscope is one of the main methods of diagnostic practice in many areas of natural science. Most modern methods of researching objects using a light microscope include preliminary preparation of objects. However, in this case it is impossible to achieve a high degree of reliability of information about the object under study.

A possibility of detecting biogenic gases by the laser optoacoustic gas-analysis method is shown. The construction and specifications of instruments, developed for this purpose, are described. Examples of the analysis of gas samples of various biological objects, like air, expired by patients, suffered from different illnesses, and residual gases in the wood of year rings of conifers are given together with recommendations on applying the received information.

A new approach to the use of nanotubes as an alloying tool for living biological objects is proposed. The basis of the mechanism of doping is chemical detonation in the nanotube. A procedure for the accelerated calculation of nanotube parameters for the purpose of doping is proposed. The possibilities of parallel programming in calculating the parameters of a detonation gas mixture are shown.

Holographic tomography (HT) is an advanced label-free optical microscopic imaging method used for biological studies. HT uses digital holographic microscopy to record the complex amplitudes of a biological sample as digital holograms and then numerically reconstruct the sample’s refractive index (RI) distribution in three dimensions. The RI values are a key parameter for label-free bio-examination, which correlate with metabolic activities and spatiotemporal distribution of biophysical parameters of cells and their internal organelles, tissues, and small-scale biological objects. This article provides insight on this rapidly growing HT field of research and its applications in biology. We present a review summary of the HT principle and highlight recent technical advancement in HT and its applications.

By fusing manifold embedding with machine learning, the researchers create an algorithm that can pick out X-ray diffraction patterns of single particles from an ocean of data.

Researches on an optimization of the filtration process of DNA nucleotides gene expression profiles are presented in the article. The data of lung cancer patients E-GEOD-68571 of Array Express database were used as experimental data. Filtration was carried out under the terms of the expression detecting of corresponding gene, herewith the variance of gene expression, the absolute value of expression and the Shannon entropy were used as criteria. The value of thresholding coefficient was estimated on the basis of average (of) proximity measure of objects within the homogenous group and between groups. 470 columns were removed in the process of data filtering, and the matrix dimension of the test data has changed from (96´7129) to (96´6659). Estimation of the quality of information processing was performed by the comparative analysis of the clustering results of processed and unprocessed data.

An original experimental stand is presented, aimed at studying the impact of high-energy protons, produced by the laser-plasma interaction at a petawatt power level, on biological objects. In the course of pilot experiments with the energy of laser-accelerated protons up to 25 MeV, the possibility is demonstrated of transferring doses up to 10 Gy to the object of study in a single shot with the magnetic separation of protons from parasitic X-ray radiation and fast electrons. The technique of irradiating the cell culture HeLa Kyoto and measuring the fraction of survived cells is developed. The ways of optimising the parameters of proton beams and the suitable methods of their separation with respect to energy and transporting to the studied living objects are discussed. The construction of the stand is intended for the improvement of laser technologies for hadron therapy of malignant neoplasms.

The problem of digital holographic imaging of optically transparent objects in arbitrary spectral intervals is discussed. An optical scheme based on Mach−Zehnder interferometer with acousto-optic filtration of broadband light is proposed, and an experimental setup is described. Digital holograms of test patterns and real biological objects are presented.

A laser medical device has been created to conduct an exact photodestruction of the vascular formations of the skin and subcutaneous tissue. Conducted studies on model biological objects for confirmation the possibility of realizing the optimal parameters of laser radiation providing photodestruction of hemoglobin containing tissues.

The possibility of noninvasive detection of magnetic particles in biological objects has been investigated. It has been found that magnetic particles, including magnetite, hematite, and catalytic iron particles in carbon nanotubes, can be detected by ultrasensitive magnetic field sensors with resolutions of 10−8-10−14 T. This research direction is shown to be promising for noninvasive monitoring of organs, implants, prosthesis, and other elements of biological systems.

It is analyzed ways and methods of contrast improvements of biological objects images, which are created by television optical microscope. Advantages of TV scanning microscope usage for biological objects images formations are reviewed. Methods of research stages which allow to improve microscope parameters are shown in this paper.

The German inventor and developer of the electron microscope, Ernst Ruska, characterised the period 1933 to 1937 as an incubation period for the commercial launch of the instrument by Siemens. Although it was only in this latter year that Ruska and his friend Bodo von Borries succeeded in finding a business ally, the brief interval saw remarkable developments in the visualisation of biological objects by means of an electron beam. Here this history is charted, in Europe and North America, for these critical years. The roles of the principal scientists involved are portrayed in detail. What emerges from this analysis is the separate development of the transmission electron microscopes and the instrument based on emission. This article extends van Gorkom's previous account in these Advances of the work of Ernst Ruska and others by relating how the instrument builders finally got backing from industry.

It was shown /1,2/ that laser FIR emission has an influence on biological objects, in particular it has the effect on cells growth velocity /2/. Investigation of FIR emission - biological object interaction mechanism needs to carry out experiments on biological macromolecules.

Electrical Impedance of biological tissues changes with the change in tissue anatomy and tissue physiology. Electrical Impedance Spectroscopy (EIS) has been studied to characterize the biological objects like fruits and vegetables for assessing their freshness. In this direction, the EIS studies have been conducted as a nondestructive investigation evaluation method to study the electrical impedance variations in banana ripening. The aim of the work is to correlate the impedance variation with the ripening process in banana. A small amount of alternating current is injected to the banana attached to impedance analyzer board AD 5933. The banana impedance and phase angles are measured from 100 Hz and 12 KHz. The results demonstrate that the electrical impedance of banana varies significantly during its ripening. From the experimental studies, it is observed that the impedance and imaginary part of the impedance are decreased and real part of the impedance was increased with the progresses in the banana ripening process.

In this article, modern technical means of obtaining, processing and analysis of images for biological objects are studied. Whole process from recording the image, to processing it, is dissected both in hardware and technical details. Information about automated systems of processing for general purpose researched, and also confocal laser scanning microscope specialized system of image processing and techniques behind the analysis for micro objects are considered. The confocal approach made it much easier to obtain images of living microobjects, made it possible to automate the accumulation of three-dimensional data, and improved images of drugs using simultaneously several fluorescent markers.

The overview demonstrates how the use of only one physico-chemical approach, viz., the electron paramagnetic resonance method, allowed detection and identification of dinitrosyl iron complexes with thiol-containing ligands in various animal and bacterial cells. These complexes are formed in biological objects in the paramagnetic (electron paramagnetic resonance-active) mononuclear and diamagnetic (electron paramagnetic resonance-silent) binuclear forms and control the activity of nitrogen monoxide, one of the most universal regulators of metabolic processes in the organism. The analysis of electronic and spatial structures of dinitrosyl iron complex sheds additional light on the mechanism whereby dinitrosyl iron complex with thiol-containing ligands function in human and animal cells as donors of nitrogen monoxide and its ionized form, viz., nitrosonium ions (NO+).

Carbon allotropes-based nanomaterials possess unique physical and chemical properties including high surface area, the possibility of pi-stacking interaction with a wide range of biological objects, rich availability of oxygen-containing functional groups in graphene-oxide (GO), and excellent optical properties, which make them an ideal candidate for use as a universal immobilization platform in SPR biosensing. Here, we propose a new surface plasmon resonance (SPR) biosensing interface for sensitive and selective detection of small molecules. This interface is based on the GO linking layers deposited on the gold/copper surface of SPR sensor chips. To estimate the binding capacity of GO layers, modification of carboxyl groups to N-Hydroxysuccinimide esters was performed in the flow cell of SPR instrument. For comparison, the same procedure was applied to commercial sensor chips based on linking layers of carboxymethylated dextran.

A microcantilever has attracted interest in an application of high sensitivity sensor for chemical, physical, or biological objects. In this paper, we investigate a possibility of a piezoresistive microcantilever for gas sensing using a static and a dynamic modes operation. The gas used here is a liquefied petroleum gas (LPG). The measurement was performed by a Wheatstone bridge circuit in order to measure the microcantilever deflection or resonance frequency shift of the microcantilever vibration. The result shows that in the static mode, an output of Wheatstone bridge circuit, which attributes to the microcantilever deflection, changes due to the gas detection. For the dynamic mode, a voltage of peak-to-peak, which represents the microcantilever vibrations, decreases with increasing the gas flow time. This occurs due to the resonance frequency shift caused by the addition of gas molecules on the microcantilever surface. These results indicate that the developed system can be used as the gas sensor.

We clearly show the existence of an example of non-contact effect in which the “presence” of a meditator affects bio-samples without physical contact. This is the first report in the world to show this type of effect by scientific measurements. We used edible cucumber slices as bio-sensors and measured the concentrations of gas emitted from the slices by a technique developed by our group. The concentrations of gas emitted from cucumber slices were measured for a total of 672 sample petri dishes; each dish contained four cucumber slices so that a statistically meaningful comparison could be made. We found a statistically significant difference (p=3.13×10-10, t-test, two-tails) in the concentrations of emitted gas between the “presence” and the “absence” of the meditator. Our experimental results clearly indicated that there was a scientifically measurable effect on biological objects with which the meditator had no direct physical contact. Key words: Non-contact effect, meditator, bio-sensor, cucumber, gas.

Results of numerical 2D and 3D-simulations of the performance of nanowire sensors on the basis of silicon-on-insulator structures aimed at determining the optimum conditions for the response to dielectric particles, are given. The effect of screening of nanowires by dielectric particles in solutions with pH = 7 used as a medium for transporting biological objects is considered.

The work contains feasibility study of independent components analysis (ICA) in bioradar data processing. The method was tested on separation of respiratory and heart beat patterns in bioradar signals. A mathematical model of a bioradar signal reflected from biological objects is presented. Mathematical simulation confirmed that ICA is appropriate if observing a single person for separating vital signs patterns even in most challenging cases (e.g., sports bradycardia). In addition, the possibility of respiration pattern extraction from bioradar data in case of biological objects observed simultaneously by means of ICA was tested on models, which confirmed the effectiveness of the proposed method.

Biological objects are composed of submicrometer structures such as cells and organelles that are essential for their functions. Here, we report on three-dimensional X-ray visualization of cells and organelles at resolutions up to 100 nm by imaging microtomography (micro-CT) equipped with Fresnel zone plate optics. Human cerebral tissue, fruit fly cephalic ganglia, and Escherichia coli bacteria labeled with high atomic-number elements were embedded in epoxy resin and subjected to X-ray microtomography at the BL37XU and BL47XU beamlines of the SPring-8 synchrotron radiation facility. The obtained results indicated that soft tissue structures can be visualized with the imaging microtomography.

A compressed sensing/sparse-recovery procedure is adopted to obtain enhanced range resolution capability from the processing of data acquired with narrow-band SFCW radars. A mathematical formulation for the proposed approach is reported and validity limitations are fully discussed, by demonstrating the ability to identify a great number of targets, up to 20, in the range direction. Both numerical and experimental validations are presented, by assuming also noise conditions. The proposed method can be usefully applied for the accurate detection of parameters with very small variations, such as those involved in the monitoring of soil deformations or biological objects.

We succeeded in 3-D motion-picture imaging for dynamic motion of biological objects swimming at different depths by parallel phase-shifting digital holographic microscopy (PPSDHM). PPSDHM is a technique for high-quality instantaneous 3-D imaging of specimens in the microscopic field of view by single-shot recording of multiple phase-shifted holograms. We constructed a PPSDHM for recording high-speed dynamic phenomena and then motions of biological objects in water were recorded at 20 000 and 150 000 frames/s, respectively, which is the fastest among the previous reports on 3-D imaging of biological objects.

The coherent phase microscopy (CPM) provides a convenient and non-invasive tool for imaging cells and intracellular organelles. In this article, we consider the applications of the CPM method to imaging different cells and energy-transducing intracellular organelles (mitochondria and chloroplasts). Experimental data presented below demonstrate that the optical path length difference of the object, which is the basic optical parameter measured by the CPM method, can serve as an indicator of metabolic states of different biological objects at cellular and subcellular levels of structural organization.

Newly constructed 4th generation sources of intense synchrotron radiation in ultrafast pulses of only 10–50 fs and wavelengths up to X-rays, the free electron lasers, are expected to revolutionize development of biological science. To take full advantage of unique properties of the sources, new imaging techniques of molecular and microscopic biological objects are developed. Present article provides a short review of a stormy development of bioimaging with incoming soon 4th generation synchrotron radiation X-ray sources. Some implications for the future of new sources and techniques are discussed as well.

Acoustothermometrical measurements were carried out for the model biological objects. As model objects we used the plasticine bodies placed in the water. In the experiment the model objects were being heated up and cooled down. The temporal dependences of their acoustobrightness temperatures were obtained and the reconstruction of the 2-D temperature distribution was made. The position, size and temperature of the thermal source were detected. The reconstruction error was about 1{2mm for the position and size and about 1K for the temperature. These results were obtained when the measurement time was about 50s. As well we carried out the acoustothermometrical control during the laser hyperthemia of the mammary gland. The medicine procedure was continued 10min and the maximum gland acoustobrightness temperature was increased at about 7degrees.

PurposeThe purpose of this paper is to present a novel microbiological lab robot that facilitates high through‐put sample preparation for rapid state‐of‐the‐art identification.Design/methodology/approachDevelopment concentrated on two main points: research initially focused on various methods for picking a micro‐organism colony from a petri dish without any medium adhering; and subsequently on completely documenting sample handling with little effort.FindingsA sensorless system for picking micro‐organisms from a petri dish was engineered and prototyped. A documented process in the demonstrator demonstrates its usability even for certified clinical operations.Research limitations/implicationsThe handling of solid phase biological objects is only in its infancy. This research focused on the preparation of samples from micro‐organism colonies for MALDI‐TOF MS. A specific type of gripper was developed to do this. The handling of other biological objects, e.g. from cell cultures or intermediate stages of tissue engineering, is still a largely open field for future research.Practical implicationsNew analysis methods often only become accepted when the preparatory processes are also taken into account – highly parallel operations (e.g. MALDI‐TOF MS) are particularly impractical for humans and difficult for data handling to manage. Given the specific demands, only an interdisciplinary team can adapt the automation engineering successfully.Originality/valueThis paper presents an approach to and implementation of the automation of manual operations in biotechnology. It is intended to encourage health professionals, biologists and engineers to jointly research and interdisciplinarily automate complex operations.

Thanks to the use of autofluorescent proteins, cell biologists are now able to observe and study the evolution of the volumetric content of live cells through time sequences of 3D images (also called 4D images). We present in this paper 4DReAM a tracking framework based on a deformable model, and how we apply it in cell biology to understand, describe, explain, in addition to interactively visualize and analyze the evolution of structures enclosed one in another, at different levels in the cell: proteins, nucleoli and nucleus. This deformable model, defined as a triangulated mesh, can automatically adapt its topology to fit the splits and merges of the biological objects. The usefulness of 4DReAM is illustrated on experimental results from different 4D images acquired by confocal microscopy.

Accepted: 2014-11-06, 資料番号: SA1150030000

In an optical tweezers system, the output signal of a photodiode quadrant detector and the temperature in a sample cell are two key factors for the quantitative measurements of mechanical properties of living biological objects such as cells, organelles and macro-molecules. In order to enhance the output of a quadrant detector and effectively control the temperature in a sample cell, the dependence of the temperature in the sample cell and the output of the quadrant detector for different illumination conditions are studied. The results show that appropriate illumination conditions can ensure both nearly constant temperatures in the cell and the desired output signal, which provides for the possibility of high precision and damage-free analysis of living biological objects.