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Machine learning-based cell classifiers use cell images to automate cell-type discrimination, which is increasingly becoming beneficial in biological studies and biomedical applications. Brightfield or fluorescence images are generally employed as the classifier input variables. We propose to use Raman spectral images and a method to extract features from these spatial patterns and explore the value of this information for cell discrimination. Raman images provide information regarding distribution of chemical compounds of the considered biological entity. Since each spectral wavelength can be used to reconstruct the distribution of a given compound, spectral images provide multiple channels of information, each representing a different pattern, in contrast to brightfield and fluorescence images. Using a dataset of single living cells, we demonstrate that the spatial information can be ranked by a Fisher discriminant score, and that the top-ranked features can accurately classify cell types. This method is compared with the conventional Raman spectral analysis. We also propose to combine the information from whole spectral analyses and selected spatial features and show that this yields higher classification accuracy. This method provides the basis for a novel and systematic analysis of cell-type investigation using Raman spectral imaging, which may benefit several studies and biomedical applications.

This study explored the performance characteristics of a cuff-leak test (CLT) combined with interventional fiberoptic bronchoscopy (FBS) for evaluating whether early nasoendotracheal extubation was possible for patients who had received transoral atlantoaxial reduction plate (TARP) internal fixation surgery. 318 patients who underwent surgery were retrospectively analyzed (between January 2006 and December 2012). Extubation was performed by conventional approach (CA group, until December 2008) and improved approach (IA group, from January 2009) including CLT and an interventional FBS procedure. The extubation success within 1–3 days after surgery, incidence of postextubation stridor and tracheal reintubation were examined. More IA-treated patients experienced extubation during the first 2 days than those CA-treated, median extubation time was 3 (2, 3) days in the CA group and 2 (1, 2) days in the IA group (all P

Raman spectral imaging is gaining more and more attention in biological studies because of its label-free characteristic. However, the discrimination of overlapping chemical contrasts has been a major challenge. In this study, we introduce an optical method to simultaneously obtain two orthogonally polarized Raman images from a single scan of the sample. We demonstrate how this technique can improve the quality and quantity of the hyperspectral Raman dataset and how the technique is expected to further extend the horizons of Raman spectral imaging in biological studies by providing more detailed chemical information. The dual-polarization Raman images of a HeLa cell.

Raman microscopy is a powerful tool for analytical imaging. The wavelength shift of Raman scattering corresponds to molecular vibrational energy. Therefore, we can access rich chemical information, such as distribution, concentration, and chemical environment of sample molecules. Despite these strengths of Raman microscopy, the spatial resolution has been a limiting factor for many practical applications. In this study, we developed a large-area, high-resolution Raman microscope by utilizing structured illumination microscopy (SIM) to overcome the spatial resolution limit. A structured line-illumination (SLI) Raman microscope was constructed. The structured illumination is introduced along the line direction by the interference of two line-shaped beams. In SIM, the spatial frequency mixing between structured illumination and Raman scattering from the sample allows access to the high spatial frequency information beyond the conventional cut-off. As a result, the FWHM of 40-nm fluorescence particle images showed a clear resolution enhancement in the line direction: 366 nm in LI and 199 nm in SLI microscope. Using the developed microscope, we successfully demonstrated high-resolution Raman imaging of various kinds of specimens, such as few-layer graphene, graphite, mouse brain tissue, and polymer nanoparticles. The high resolution Raman images showed the capability to extract original spectral features from the mixed Raman spectra of a multi-component sample because of the enhanced spatial resolution, which is advantageous in observing complex spectral features. The Raman microscopy technique reported here enables us to see the detailed chemical structures of chemical, biological, and medical samples with a spatial resolution smaller than 200 nm.

Indium oxide (In2O3) nanorods, nanotowers and tin-doped (Sn:In = 1:100) indium oxide (ITO) nanorods have been fabricated by thermal evaporation. The morphology, microstructure and chemical composition of these three nanoproducts are characterized by FE-SEM, HRTEM and XPS. To further investigate the optoelectronic properties, the I–V curves and cathodoluminescence (CL) spectra are measured. The electrical resistivity of In2O3 nanorods, nanotowers and ITO nanorods are 1.32 kΩ, 0.65 kΩ and 0.063 kΩ, respectively. CL spectra of these three nanoproducts clearly indicate that tin-doped (Sn:In = 1:100) indium oxide (ITO) nanorods cause a blue shift. No doubt ITO nanorods obtain the highest performance among these three nanoproducts, and this also means that Sn-doped In2O3 nanostructures would be the best way to enhance the optoelectronic properties. Additionally, the growing mechanism and the optoelectronic properties of these three nanostructures are discussed. This study is beneficial to the applications of In2O3 nanorods, nanotowers and ITO nanorods in optoelectronic nanodevices.

Shortly after its development, the white light supercontinuum laser was applied to confocal scanning microscopy as a more versatile substitute for the multiple monochromatic lasers normally used for the excitation of fluorescence. This light source is now available coupled to commercial confocal fluorescence microscopes. We have evaluated a supercontinuum laser as a source for a different purpose: confocal interferometric imaging of living cells and artificial models by interference reflection. We used light in the range 460–700 nm where this source provides a reasonably flat spectrum, and obtained images free from fringe artefacts caused by the longer coherence length of conventional lasers. We have also obtained images of cytoskeletal detail that is difficult to see with a monochromatic laser.

In the last couple of decades, the spatial resolution in optical microscopy has increased to unprecedented levels by exploiting the fluorescence properties of the probe. At about the same time, Raman imaging techniques have emerged as a way to image inherent chemical information in a sample without using fluorescent probes. However, in many applications, the achievable resolution is limited to about half the wavelength of excitation light. Here we report the use of structured illumination to increase the spatial resolution of label-free spontaneous Raman microscopy, generating highly detailed spatial contrast from the ensemble of molecular information in the sample. Using structured line illumination in slit-scanning Raman microscopy, we demonstrate a marked improvement in spatial resolution and show the applicability to a range of samples, including both biological and inorganic chemical component mapping. This technique is expected to contribute towards greater understanding of chemical component distributions in organic and inorganic materials., Raman imaging provides visualization of molecular content in a sample, but has been practically limited in resolution. Here, the authors implement structured line illumination in slit-scanning Raman microscopy, expanding its resolvable spatial frequencies without spoiling the advantage of the Raman approach.

In this paper, the Lateral Positive-Intrinsic-Negative (LPIN) diode and its application in the high efficiency silicon-based plasma antenna are introduced. A LPIN diode can be employed as a plasma island when sufficient DC power is supplied, which can be used for reconfigurable antennas. The conductivity of intrinsic layer is simulated using the finite element method (FEM). The frequency reconfigurable dipole antenna is design based on LPIN diode array, which comprises 24 LPIN diodes. These research results of this paper can provide theoretical basis for further development of high efficiency frequency reconfigurable silicon-based plasma antenna.

Using Raman spectral imaging, we visualized the cell state transition during differentiation and constructed hypothetical potential landscapes for attractors of cellular states on a state space composed of parameters related to the shape of the Raman spectra. As models of differentiation, we used the myogenic C2C12 cell line and mouse embryonic stem cells. Raman spectral imaging can validate the amounts and locations of multiple cellular components that describe the cell state such as proteins, nucleic acids and lipids; thus, it can report the state of a single cell. Herein, we visualized the cell state transition during differentiation using Raman spectral imaging of cell nuclei in combination with principal component analysis. During differentiation, cell populations with a seemingly homogeneous cell state before differentiation showed heterogeneity at the early stage of differentiation. At later differentiation stages, the cells returned to a homogeneous cell state that was different from the undifferentiated state. Thus, Raman spectral imaging enables us to illustrate the disappearance and reappearance of an attractor in a differentiation landscape, where cells stochastically fluctuate between states at the early stage of differentiation.

Raman spectral imaging has become a more and more popular technique in biological studies because it can extract chemical information from living cells in a label-free manner. One of the most challenging issues in the label-free Raman imaging of biological samples is to increase the molecular specificity in the spectra for better chemical contrast. Usually, the Raman spectrum from a cell is dominated by a few strong Raman bands such as the amide I band around 1650 cm -1 , CH 2 bend around 1445 cm -1 or the amide III band around 1300 cm -1 and it is not easy to get chemical contrast from other Raman bands that overlap with them. In this study, we aim to manipulate the chemical contrast in a living cell by exploiting the polarisation effects in Raman spectroscopy. By simply putting an analyser before the spectrometer, we can take the Raman image at the parallel and perpendicular polarisation against the incident light at the sample. The Raman spectra at the two orthogonal polarisations represent the Raman signals with different molecular orientation and symmetry of vibrations. Our experimental results demonstrate that at certain Raman shifts the two orthogonal polarisations indeed present different chemical contrasts. This indicates that polarized Raman imaging can help us visualise the different chemical contrasts that overlap at the same Raman shift and therefore increase the amount of chemical information we can get from cells.

Protein-protein interactions (PPIs) are central for most biological processes. Much effort has been put into the development of methodology for predicting PPIs and the construction of PPIs networks. Though a high accurate rate those methods have achieved, it was found that the accurate rate strongly depends on the balance of datasets. Compare to negative datasets, positive datasets contain some proteins which are called hub protein intact more proteins. And the unbalance between datasets leads to an excellent performance of PPIs prediction. But when one used balance datasets, the performance is disappointed. Different Biological functions are supported by different local PPIs network. Does it mean that local PPIs network has its own feature? In this paper, we managed to catch features of local networks in three species on the condition that there is no unbalance between positive dataset and negative dataset. Features of local PPIs network fades as the network extended. The associate rules method is used to analyze features of local PPI network. All the datasets used in this study are derived from public available database.

The traditional spatial distributions of GDP(Gross domestic product) are calculated on the basis of administrative boundaries. This paper establishes a simulated spatial GDP model and update model instead of the traditional statistical distributions of social and economic output value which based on administrative boundaries. We use the grid analysis technology and statistical analysis technology, studies the pertinence between the land-use situation and the spatial distribution of GDP through researching the relationships among all kinds of geographical variable, then establishes the spatial distributed model of GDP. Based on the analysis of the key part of grid GDP update, the paper puts forward a grid GDP update model based on administrative polygon borders according to the simple scale model and the environmental terms' area scale model. It resolves those problems exiting in the old method which made the spatial orientation inaccurate, inexactitude, not unification, and a series of spatial data incompact integration.

The shot based clustering and retrieval is very important for video database organization and access. We can take advantage of semantic clustering to enhance the performance of traditional content-based video retrieval. In this paper, text feature and color feature are first extracted directly from shots. Subsequently, a two-level hierarchical clustering structure that provides indexing scheme for retrieval is constructed by incorporating text and color features. The top level is clustered by text features while the bottom level is clustered by color features. The constructed structure is then used for the cluster-based retrieval. The effectiveness and efficiency of our approach are demonstrated by the experimental results in retrieving and ranking similar video shots.

A fiber-optic surface plasmon resonance sensor (SPR) based on tapered structure probe is studied. The incentive mode of tapered probe calculated by finite-difference time-domain method serves as design references, and the tapered structure of sensor probe fabricated by polishing and grinding at the end of a fiber is similar to Kretschmann prism SPR model, which can realize the modulation of SPR wave. The results show that in the refractive index detection range from 1.3330 to 1.4215, tapered structure FO-SPR sensor has a sensitivity of 1-6 times higher than common FO-SPR sensor and it still keeps a limiting resolution level of 10-5 RIU. The designed tapered structure SPR sensor, which has the advantages of tapered incentive mode, design flexibility, user practical applicability, simple preparation process, a relatively small sample need, and high stability, will fulfill different environment and measuring conditions of biochemical testing and environment monitoring.

The influence of the monitoring point wavelength on the axial strain sensitivity of high-birefringence fiber loop mirror is investigated. The theoretical expression for the axial strain sensitivity of high-birefringence fiber loop mirror is developed. The results show that the sensitivity increases with the wavelength of the monitoring point increasing when the high-birefringence fiber material is certain, that the sensitivity is constant and the wavelength shift is linear versus strain for the certain monitoring point. The axial strain sensitivities of the different wave peaks are monitored in experiment. The experimental results of data fitting are in good agreement with the theoretical ones. The research results help to improve the strain sensitivity, the temperature sensitivity, etc. of high-birefringence fiber loop mirror.