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Fourier transform infrared microscopy imaging (FT-IRI) can be used to collect the infrared spectra and morphology of the samples. As combined with chemometric method, the content and spatial distribution of the principal components in biological tissues can be studied quantitatively. In this study, FT-IRI combined with principal component analysis (PCA) and Fisher discriminant analysis (FDA) was applied to identify healthy and degenerated articular cartilage samples. First, FT-IRI and spectral analysis on articular cartilage specimens were achieved, as well as PCA on the infrared spectra in SPSS software. And then FDA was adopted to construct the classification function based on the principal component score matrix for classifying the articular cartilage samples. The healthy and degenerated cartilage samples were effectively discriminated with very high accuracy of 95.7% for initial samples and 94.3% for cross-validation, respectively. It is indicated that the hyphenated technique can be used to effectively discriminate the healthy and degenerated cartilages, which opens a newly effective way of monitoring osteoarthritis generation and reparation.

This paper used solidworks software to build 3-D model of a certain Heavy Vehicle Part, then analyzed the model strain state under typical operation condition by ANSYS

Grain boundaries hinder twin boundary motion in magnetic shape-memory alloys and suppress magnetic-field-induced deformation in randomly textured polycrystalline material. The quest for high-quality single crystals and the associated costs are a major barrier for the commercialization of magnetic shape-memory alloys. Adding porosity to polycrystalline magnetic-shape memory alloys presents solutions for (i) the elimination of grain boundaries via the separation of neighboring grains by pores, and (ii) the reduction of production cost via replacing the directional solidification crystal growth process by conventional casting. Ni-Mn-Ga foams were produced with varying pore architecture and pore fractions. Thermo-magnetic training procedures were applied to improve magnetic-field-induced strain. The cyclic strain was measured in-situ while the sample was heated and cooled through the martensitic transformation. The magnetic field-induced strain amounts to several percent in the martensite phase, decreases continuously during the transformation upon heating, and vanishes in the austenite phase. Upon cooling, cyclic strain appears below the martensite start temperature and reaches a value larger than the initial strain in the martensite phase, thereby confirming a training effect. For Ni-Mn-Ga single crystals, external constraints imposed by gripping the crystal limit lifetime and/or magnetic-field-induced deformation. These constraints are relaxed for foams.

SiCw/Al-18Si composites were prepared by squeeze casting technique. SiCw/Al-18Si composites were remelted before solidification. The effects of volume fraction of SiC whisker on solidification behavior of SiCw/Al-18Si composites were investigated by means of differential scanning calorimetry (DSC) technique and microstructure observation. DSC results indicated that the start solidification temperature and primary silicon peak temperature decreased gradually and the degree of supercooling increased with the increasing of SiC whisker content. SiC whisker and Sr decreased the average size of Si phases and improved the mechanical properties of the composites.

It is attractive to use multi-wall carbon nanotubes (MWNTs), which has a high modulus and strength, to enhance the properties of metal matrix composites by hybrid strategy. In this paper, novel aluminum borate whisker (ABOw) and MWNTs hybrid composites were prepared by squeeze cast technique and the properties were investigated. The results show that hybrid preforms may be made by co-deposition of ABOw and MWNTs in a solution by wet method. MWNTs separate the ABOw from whisker-to-whisker contact and decrease the compressive deformation of the hybrid preforms during squeeze cast processing. MWNTs distribute along mainly in the grains of aluminum matrix, making the mechanical properties of the hybrid composites higher than singularly reinforced composite.

Fourier transform infrared imaging (FTIRI) combined with chemometrics algorithm has strong potential to obtain complex chemical information from biology tissues. FTIRI and partial least squares-discriminant analysis (PLS-DA) were used to differentiate healthy and osteoarthritic (OA) cartilages for the first time. A PLS model was built on the calibration matrix of spectra that was randomly selected from the FTIRI spectral datasets of healthy and lesioned cartilage. Leave-one-out cross-validation was performed in the PLS model, and the fitting coefficient between actual and predicted categorical values of the calibration matrix reached 0.95. In the calibration and prediction matrices, the successful identifying percentages of healthy and lesioned cartilage spectra were 100% and 90.24%, respectively. These results demonstrated that FTIRI combined with PLS-DA could provide a promising approach for the categorical identification of healthy and OA cartilage specimens.

Solidification behavior of SiCw/Al-18Si metal matrix composites (MMCs) was studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and differential scanning calorimeter (DSC) in order to reveal the effects of strontium addition and whisker content. The results show that the Si phase does not nucleate on SiC whisker surface. With the increasing of SiC whisker content, solidification onset and peak temperatures of primary Si decrease. Sr addition lowers solidification onset and peak temperatures of primary Si, and reduces its size. Whisker content has larger effects on solidification onset and peak temperatures of primary Si without Sr addition than that of primary Si with Sr addition.But solidification onset and peak temperatures of eutectic are barely affected by whisker content and Sr addition.

Two discriminant methods, partial least squares-discriminant analysis (PLS-DA) and Fisher’s discriminant analysis (FDA), were combined with Fourier transform infrared imaging (FTIRI) to differentiate healthy and osteoarthritic articular cartilage in a canine model. Osteoarthritic cartilage had been developed for up to two years after the anterior cruciate ligament (ACL) transection in one knee. Cartilage specimens were sectioned into 10 [Formula: see text]m thickness for FTIRI. A PLS-DA model was developed after spectral pre-processing. All IR spectra extracted from FTIR images were calculated by PLS-DA with the discriminant accuracy of 90%. Prior to FDA, principal component analysis (PCA) was performed to decompose the IR spectral matrix into informative principal component matrices. Based on the different discriminant mechanism, the discriminant accuracy (96%) of PCA-FDA with high convenience was higher than that of PLS-DA. No healthy cartilage sample was mis-assigned by these two methods. The above mentioned suggested that both integrated technologies of FTIRI-PLS-DA and, especially, FTIRI-PCA-FDA could become a promising tool for the discrimination of healthy and osteoarthritic cartilage specimen as well as the diagnosis of cartilage lesion at microscopic level. The results of the study would be helpful for better understanding the pathology of osteoarthritics.

Fourier transform infrared imaging (FTIRI) combined with chemometrics can be used to detect the structure of bio-macromolecule, measure the concentrations of some components, and so on. In this study, FTIRI with Partial Least-Squares (PLS) regression was applied to study the concentration of two main components in bovine nasal cartilage (BNC), collagen and proteoglycan. An infrared spectrum library was built by mixing the collagen and chondroitin 6-sulfate (main of proteoglycan) at different ratios. Some pretreatments are needed for building PLS model. FTIR images were collected from BNC sections at 6.25μm and 25μm pixel size. The spectra extracted from BNC-FTIR images were imported into the PLS regression program to predict the concentrations of collagen and proteoglycan. These PLS-determined concentrations are agreed with the result in our previous work and biochemical analytical results. The prediction shows that the concentrations of collagen and proteoglycan in BNC are comparative on the whole. However, the concentration of proteoglycan is a litter higher than that of collagen, to some extent.

Fourier transform infrared spectroscopic imaging (FTIRI) technique can be used to obtain the quantitative information of content and spatial distribution of principal components in cartilage by combining with chemometrics methods. In this study, FTIRI combining with principal component analysis (PCA) and Fisher's discriminant analysis (FDA) was applied to identify the healthy and osteoarthritic (OA) articular cartilage samples. Ten 10-μm thick sections of canine cartilages were imaged at 6.25μm/pixel in FTIRI. The infrared spectra extracted from the FTIR images were imported into SPSS software for PCA and FDA. Based on the PCA result of 2 principal components, the healthy and OA cartilage samples were effectively discriminated by the FDA with high accuracy of 94% for the initial samples (training set) and cross validation, as well as 86.67% for the prediction group. The study showed that cartilage degeneration became gradually weak with the increase of the depth. FTIRI combined with chemometrics may become an effective method for distinguishing healthy and OA cartilages in future.

To investigate the effects of bleomycin (BLM) on the apoptosis of type II alveolar epithelial cell (AT II) in lung fibrotic rats and its possible mechanisms.Totally 32 male Sprague-Dawley rats were randomly divided into sham group (n = 8) and BLM group (n = 24). Rats in sham group or BLM group were intratracheally instillated with saline or 5 mg/kg of bleomycin, respectively. One, three, and seven days after the instillation of bleomycin, 8 rats in BLM group were taken for AT II isolation and purification. Rats in sham group were used to isolate and purify AT II on 7 days after the instillation of saline. The cell cycle and apoptosis, intracellular free calcium concentration, and mitochondrial membrane potential (MMP) in AT II were determined by flow cytometry. Immunohistochemistry was performed to observe the expressions of Bax, Bcl-2, and Fas. Caspase-3, Caspase-8, and Caspase-9 activities were measured by Caspase activity detection kit.The ratio of S phase AT II in BLM group was significantly lower than in sham group (P0.05). AT II apoptosis rates on day 1 and 3 were significantly higher in BLM group than in sham group (P0.01). Intracellular free calcium concentrations in BLM group were significantly higher than in sham group (P0.05). However, MMP was significantly lower than sham group (P0.05). The positive rates of Bax, Fas and Caspase-3, Caspase-8, and Caspase-9 activities of BLM group were significantly higher than those of sham group (P0.05, P0.01). The positive rates of Bcl-2 on day 1 and 3 were significantly lower than those of sham group (P0.05).Early AT II apoptosis may be induced by bleomycin, which may be explained by the increase of intracellular free calcium concentration, depression of MMP, increased expressions of Fas and Bax, and increase of Caspase-3, Caspase-8, and Caspase-9 activities.

Image segmentation based on graph theory is mainly used for gray image now, and thresholding of segmentation should be predefined. Combining with maximum between -and- within -class in statistics theory, this paper suggests an unsupervised method for color image segmentation. The image is mapped into an weighted undirected graph, the pixels are considered as nodes, and minimum spanning tree is constructed by Kruskal algorithm .The best thresholding is obtained by maximum objective function to realize unsupervised segmentation. Experiment results show that the new algorithm ensures the color image segmentation excellent disturbance attenuation performance and better separability.

Objective To summarize the experience and method of endovascular treatment of unilateral A1 segment anterior communicating artery aneurysm with detachable coils.Methods Forty-eight patients with unilateral A1 anterior communicating artery aneurysm(23 males and 25 females,age ranged from 32 to 72 years with mean of 53.4,hospitalized in Xijing hospital from Jan.2009 to Apr.2010) were involved in present study.All of the aneurysms were measured with rotational digital subtraction angiography(RDSA) and image post-processing techniques,and they were embolized with Guglielmi detachable coils(GDCs).The patency of the parent arteries was monitored by catheterization in both carotid arteries in the process of treatment.Stent-assisted,balloon remodeling,microcatheter and microwire assisted techniques were used in the treatment of wide-necked aneurysm to keep patency of parent arteries.Cerebral angiography was performed in 38 cases 6 months after the operation to observe the patency of embolized aneurysms and anterior communicating arteries.Results Of the 48 cases,total occlusion was achieved in 39(81.3%),more than 90% occlusion was achieved in 6(12.5%),and 3(6.3%) with less than 90% occlusion;1 had hemorrhage during embolization,3 had anterior communicating artery occlusion,and 2 had contralateral internal carotid artery compensation after anterior communicating artery occlusion.No re-bleeding was found during the 6 months follow-up period.Cerebral angiography showed total occlusion of aneurysms and patency of anterior communicating arteries in 38 cases during re-examination.Conclusion The anterior communicating arteries should be kept patent in embolization treatment of the major unilateral blood supply anterior communicating artery aneurysms,and it is helpful to use microcatheter or microwire assisted techniques.