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1.
A highly flexible, stretchable, and mechanically robust low‐cost soft composite consisting of silicone polymers and water (or hydrogels) is reported. When combined with conventional acoustic transducers, the materials reported enable high performance real‐time monitoring of heart and respiratory patterns over layers of clothing (or furry skin of animals) without the need for direct contact with the skin. The approach enables an entirely new method of fabrication that involves encapsulation of water and hydrogels with silicones and exploits the ability of sound waves to travel through the body. The system proposed outperforms commercial, metal‐based stethoscopes for the auscultation of the heart when worn over clothing and is less susceptible to motion artefacts. The system both with human and furry animal subjects (i.e., dogs), primarily focusing on monitoring the heart, is tested; however, initial results on monitoring breathing are also presented. This work is especially important because it is the first demonstration of a stretchable sensor that is suitable for use with furry animals and does not require shaving of the animal for data acquisition.  相似文献   
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This paper describes the design and fabrication of electrically controlled paper actuators that operate based on the dimensional changes that occur in paper when the moisture absorbed on the surface of the cellulose fibers changes. These actuators are called “Hygroexpansive Electrothermal Paper Actuators” (HEPAs). The actuators are made from paper, conducting polymer, and adhesive tape. They are lightweight, inexpensive, and can be fabricated using simple printing techniques. The central element of the HEPAs is a porous conducting path (used to provide electrothermal heating) that changes the moisture content of the paper and causes actuation. This conducting path is made by embedding a conducting polymer (PEDOT:PSS) within the paper, and thus making a paper/polymer composite that retains the porosity and hydrophilicity of paper. Different types of HEPAs (straight, precurved, and creased) achieved different types of motions (e.g., bending motion, accordion type motion). A theoretical model for their behavior is proposed. These actuators have been used for the manipulation of liquids and for the fabrication of an optical shutter.  相似文献   
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With more than 25 million people affected, heart failure (HF) is a global threat. As energy production pathways are known to play a pivotal role in HF, we sought here to identify key metabolic changes in ischemic- and non-ischemic HF by using a multi-OMICS approach. Serum metabolites and mRNAseq and epigenetic DNA methylation profiles were analyzed from blood and left ventricular heart biopsy specimens of the same individuals. In total we collected serum from n = 82 patients with Dilated Cardiomyopathy (DCM) and n = 51 controls in the screening stage. We identified several metabolites involved in glycolysis and citric acid cycle to be elevated up to 5.7-fold in DCM (p = 1.7 × 10−6). Interestingly, cardiac mRNA and epigenetic changes of genes encoding rate-limiting enzymes of these pathways could also be found and validated in our second stage of metabolite assessment in n = 52 DCM, n = 39 ischemic HF and n = 57 controls. In conclusion, we identified a new set of metabolomic biomarkers for HF. We were able to identify underlying biological cascades that potentially represent suitable intervention targets.  相似文献   
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The development of multifunctional nanoscale systems that can mediate efficient tumor targeting, together with high cellular internalization, is crucial for the diagnosis of glioma. The combination of imaging agents into one platform provides dual imaging and allows further surface modification with targeting ligands for specific glioma detection. Herein, transferrin (Tf)-decorated niosomes with integrated magnetic iron oxide nanoparticles (MIONs) and quantum dots (QDs) were formulated (PEGNIO/QDs/MIONs/Tf) for efficient imaging of glioma, supported by magnetic and active targeting. Transmission electron microscopy confirmed the complete co-encapsulation of MIONs and QDs in the niosomes. Flow cytometry analysis demonstrated enhanced cellular uptake of the niosomal formulation by glioma cells. In vitro imaging studies showed that PEGNIO/QDs/MIONs/Tf produces an obvious negative-contrast enhancement effect on glioma cells by magnetic resonance imaging (MRI) and also improved fluorescence intensity under fluorescence microscopy. This novel platform represents the first niosome-based system which combines magnetic nanoparticles and QDs, and has application potential in dual-targeted imaging of glioma.  相似文献   
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In this study, Generalized Regression Neural Networks (GRNN) and Feed Forward Neural Networks (FFNN) approaches are used to predict the scour depth around circular bridge piers. Hundred and sixty five data collected from various experimental studies, are used to predict equilibrium scour depth. The model consisting of the combination of dimensional data involving the input variables is constructed. The performance of the models in training and testing sets are compared with observations. Then, the model is also tested by Multiple Linear Regression (MLR) and empirical formula. The results of all approaches are compared in order to get more reliable comparison. The results indicated that GRNN can be applied successfully for prediction of scour depth around circular bridge piers.  相似文献   
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Abstract: In this study, ophthalmic arterial Doppler signals were obtained from 200 subjects, 100 of whom suffered from ocular Behcet disease while the rest were healthy subjects. An adaptive neuro-fuzzy inference system (ANFIS) was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by the fast Fourier transform method for determining the ANFIS inputs. The ANFIS was trained with a training set and tested with a testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the ANFIS. The correct classification rate was 94% for healthy subjects and 90% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the ANFIS was effective at detecting ophthalmic arterial Doppler signals from subjects with Behcet disease.  相似文献   
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This study investigates an application of genetic programming (GP) for the prediction of peak ground acceleration (PGA) using strong-ground-motion data from Turkey. The input variables in the developed GP model are the average shear-wave velocity, earthquake source to site distance and earthquake magnitude, and the output is the PGA values. The proposed GP model is based on the most reliable database compiled for earthquakes in Turkey. The results show that the consistency between the observed PGA values and the predicted ones by the GP model yields relatively high correlation coefficients (R2=0.75). The proposed model is also compared with an existing attenuation relationship and found to be more accurate.  相似文献   
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In this paper, a notch analysis model is presented for the numerical prediction of multiaxial strains of a notched 1070 steel specimen under combined axial and torsion loadings. The proposed model is based on the notion of a structural yield surface and uses a small-strain cyclic plasticity model to describe stress–strain relations. A notch load–strain curve is calculated with Neuber’s rule and incremental nonlinear finite element analysis. The presented model is applied to simulate the notch root deformations of a circumferentially notched specimen under cyclic tension–compression–torsion loading histories. The model predictions are evaluated with strain measurements at the notch root of the specimen in a comprehensive set of cyclic tests. The computed strain loops were in accord with experimental data and matched qualitatively with measured shear–axial strain histories irrespective of loading path of the test. In proportional balanced torsion-axial loading, the nonlinear shear strain–axial strain loops were calculated properly. The modeling errors were determined to be a function of the loading path shape, and compared to shear strains, axial strain predictions were more accurate.  相似文献   
10.
The aim of this study was to evaluate the ex vivo expansion of normal CD34+ cells in gas-permeable polypropylene bags suitable for clinical use. Cells were cultured for 14 days in serum-free medium supplemented with SCF, IL3, IL6, FLT3-1, G-CSF + MGDF or Epo. The bags supported the expansion of hematopoietic cells in a similar manner to small scale well or flask systems, allowing mean expansions of up to 2193-fold for total nucleated cells, 140-fold for CFU-GM and 66-fold for LTC-IC. Increasing the initial cell concentration from 5 x 10(3) to 1 x 10(5)CD34+ cells/ml induced the production of granulocytic cells with terminal differentiation while simultaneously decreasing the overall extent of expansion of the white blood cells produced. We tested the phagocytic activity and oxidative metabolism of the white blood cells produced. The percentage of phagocytic cells was 39+/-0.5% in expanded cultures derived from fractions initiated at 5 x 10(3), 10(4) or 10(5) cells/ml and 45+/-6% in cultured cells obtained from starting fractions containing 5 x 10(4) cells/ml, as compared to 58+/-4% in normal controls. A study of the potential for oxygen-dependent microbe killing showed that the expanded cells produced H2O2, although in lesser quantities than control cells. We subsequently investigated the possibility of freezing expanded cells. Total cell recovery after thawing was 45+/-4%, while recoveries of progenitors and stem cells ranged from 65 to 90%, without any influence of the initial cell concentration. This new approach could be of major interest for clinical practice, as it would allow evaluation of the quality of a graft prior to its infusion and employs experimental conditions which meet the criteria for potential clinical use.  相似文献   
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