Multivariate statistical methods were applied to data sets of measured gelling properties of blue whiting mince with several hydrocolloids added (locust bean gum, guar gum, xanthan gum, carboxymethylcellulose, 1-carrageenan, 3-carrageenan or alginate) induced under different pressure-time-temperature gelling conditions. The main differences between gels were attributed to the process; all the gels were classified in three clusters on the basis of gelling treatment: (1) high-pressure at moderate heating, (2) high-pressure at cold temperature and (3) heating at atmospheric pressure. Cluster 1 was characterized by very elastic, light gels with high water holding capacity. In cluster 2, gels presented high puncture test properties (breaking deformation, breaking force, work of penetration) and high cohesiveness and water holding capacity. Cluster 3 gels presented low penetration test properties and cohesiveness; high adhesiveness and hardness; high lightness and yellowness. Each cluster was subdivided to describe the gel properties between the hydrocolloid groups, attributing the differences mainly to yellowness (b*), breaking deformation, breaking force and work of penetration. 相似文献
The Smithsonian Institution's National Museum of American History houses the largest remaining collection of inter-positive composite glass plate images from the production of Eadweard Muybridge's Animal Locomotion series. These photographs, which are approximately 150 years old, exhibit a wide range of degradation phenomena and products, including alteration of the glass plates. Compositions of both the image-bearing glass plates and support glass panels were obtained through quantitative scanning electron microscope–energy-dispersive spectrometry. Electron imaging of cross-sectioned samples of the image-bearing glass plates reveals a visible sodium-depleted glass alteration layer. Furthermore, electron imaging shows delamination of the image-containing gelatin layer and captures evidence that suggests that interfacial stresses between the glass alteration layer and the unaltered glass contribute to the delamination of this layer along with the overlaid gelatin. 相似文献
The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system offers great opportunities for the treatment of numerous diseases by precise modification of the genome. The functional unit of the system is represented by Cas9/sgRNA ribonucleoproteins (RNP), which mediate sequence-specific cleavage of DNA. For therapeutic applications, efficient and cell-specific transport into target cells is essential. Here, Cas9 RNP nanocarriers are described, which are based on lipid-modified oligoamino amides and folic acid (FolA)-PEG to realize receptor-mediated uptake and gene editing in cancer cells. In vitro studies confirm strongly enhanced potency of receptor-mediated delivery, and the nanocarriers enable efficient knockout of GFP and two immune checkpoint genes, PD-L1 and PVR, at low nanomolar concentrations. Compared with non-targeted nanoparticles, FolA-modified nanocarriers achieve substantially higher gene editing including dual PD-L1/PVR gene disruption after injection into CT26 tumors in vivo. In the syngeneic mouse model, dual disruption of PD-L1 and PVR leads to CD8+ T cell recruitment and distinct CT26 tumor growth inhibition, clearly superior to the individual knockouts alone. The reported Cas9 RNP nanocarriers represent a versatile platform for potent and receptor-specific gene editing. In addition, the study demonstrates a promising strategy for cancer immunotherapy by permanent and combined immune checkpoint disruption. 相似文献
To provide respiratory motion correction for free-breathing myocardial T1 mapping using a pilot tone (PT) and a continuous golden-angle radial acquisition.
Materials and methods
During a 45 s prescan the PT is acquired together with a dynamic sagittal image covering multiple respiratory cycles. From these images, the respiratory heart motion in head-feet and anterior–posterior direction is estimated and two linear models are derived between the PT and heart motion. In the following scan through-plane motion is corrected prospectively with slice tracking based on the PT. In-plane motion is corrected for retrospectively. Our method was evaluated on a motion phantom and 11 healthy subjects.
Results
Non-motion corrected measurements using a moving phantom showed T1 errors of 14 ± 4% (p < 0.05) compared to a reference measurement. The proposed motion correction approach reduced this error to 3 ± 4% (p < 0.05). In vivo the respiratory motion led to an overestimation of T1 values by 26 ± 31% compared to breathhold T1 maps, which was successfully corrected to an average difference of 3 ± 2% (p < 0.05) between our free-breathing approach and breathhold data.
Discussion
Our proposed PT-based motion correction approach allows for T1 mapping during free-breathing with the same accuracy as a corresponding breathhold T1 mapping scan.
Railway Engineering Science - Given that the current ballasted tracks in Australia may not be able to support faster and significantly heavier freight trains as planned for the future, the imminent... 相似文献
Abstract: Tropical cyclones (TC) are often associated with severe weather conditions which cause great losses to lives and property. The precise classification of cyclone tracks is significantly important in the field of weather forecasting. In this paper we propose a novel hybrid model that integrates ontology and Support Vector Machine (SVM) to classify the tropical cyclone tracks into four types of classes namely straight, quasi-straight, curving and sinuous based on the track shape. Tropical Cyclone TRacks Ontology (TCTRO) described in this paper is a knowledge base which comprises of classes, objects and data properties that represent the interaction among the TC characteristics. A set of SWRL (Semantic Web Rule Language) rules are directly inserted to the TCTRO ontology for reasoning and inferring new knowledge from ontology. Furthermore, we propose a learning algorithm which utilizes the inferred knowledge for optimizing the feature subset. According to experiments on the IBTrACS dataset, the proposed ontology based SVM classifier achieves an accuracy of 98.3% with reduced classification error rates. 相似文献
Fetoscopic interventions to treat fetal anomalies are currently performed for a variety of conditions. Depending on the procedure, preterm rupture of the fetal membranes (FMs) happens in around 30% of the cases, potentially leading to preterm birth and fetal morbidity and mortality. Here, the capacity of modular transglutaminase crosslinked poly(ethylene glycol) (TG-PEG) hydrogels that release platelet-derived growth factor (PDGF)-BB to promote FM healing is described. In vitro, such growth factor-loaded hydrogels are able to stimulate amniotic cell migration and proliferation. When applied in vivo, these TG-PEG hydrogels tightly seal the FM and uterus defects created by a fetoscope and remain stable for 10 days. The migration of healing-related cells into such hydrogels in the myometrium, endometrium, and FM areas is only possible in soft TG-PEG hydrogels. Importantly, bioengineered hydrogels releasing PDGF-BB promote recruitment of host cells from the myometrium and the endometrium, and to a lesser extent from FM areas. In such hydrogels, the potent proliferation and matrix production of the recruited cells at the site of treatment into the biomaterial initiates a robust early healing response. PDGF-BB-loaded TG-PEG hydrogels hold great promise for the treatment of fetoscopy-induced FM defects and for the prevention of preterm birth. 相似文献
Tungsten is an important material for high-temperature applications due to its high chemical and thermal stability. Its carbide, that is, tungsten carbide, is used in tool manufacturing because of its outstanding hardness and as a catalyst scaffold due to its morphology and large surface area. However, microstructuring, especially high-resolution 3D microstructuring of both materials, is a complex and challenging process which suffers from slow speeds and requires expensive specialized equipment. Traditional subtractive machining methods, for example, milling, are often not feasible because of the hardness and brittleness of the materials. Commonly, tungsten and tungsten carbide are manufactured by powder metallurgy. However, these methods are very limited in the complexity and resolution of the produced components. Herein, tungsten ion-containing organic–inorganic photoresins, which are patterned by two-photon lithography (TPL) at micrometer resolution, are introduced. The printed structures are converted to tungsten or tungsten carbide by thermal debinding and reduction of the precursor or carbothermal reduction reaction, respectively. Using TPL, complex 3D tungsten and tungsten carbide structures are prepared with a resolution down to 2 and 7 μm, respectively. This new pathway of structuring tungsten and its carbide facilitates a broad range of applications from micromachining to metamaterials and catalysis. 相似文献
In chemical engineering and other areas of mathematics and engineering sciences, systems of non-linear algebraic equations often must be solved, and a problem is that these types of systems often cannot be solved analytically. Homotopic continuation methods are globally convergent and can find several solutions to the analyzed algebraic system and consist of a predictive step followed by a corrective step, which can cause reversion of homotopic path tracking. Therefore, in this work, the use of a homotopy continuation method (HCM) based on a purely predictive methodology is proposed; that is, it only makes use of predictor vectors (without correction vectors) to find the solution to several systems of non-linear algebraic equations with a multiplicity of solutions, employing lower central proccessing unit (CPU) time in comparison with standard homotopic tracking algorithms. 相似文献