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31.
Rita Bonfiglio Annarita Granaglia Raffaella Giocondo Manuel Scimeca Elena Bonanno 《International journal of molecular sciences》2021,22(1)
The presence of calcium deposits in human lesions is largely used as imaging biomarkers of human diseases such as breast cancer. Indeed, the presence of micro- or macrocalcifications is frequently associated with the development of both benign and malignant lesions. Nevertheless, the molecular mechanisms involved in the formation of these calcium deposits, as well as the prognostic significance of their presence in human tissues, have not been completely elucidated. Therefore, a better characterization of the biological process related to the formation of calcifications in different tissues and organs, as well as the understanding of the prognostic significance of the presence of these calcium deposits into human tissues could significantly improve the management of patients characterized by microcalcifications associated lesions. Starting from these considerations, this narrative review highlights the most recent histopathological and molecular data concerning the formation of calcifications in breast, thyroid, lung, and ovarian diseases. Evidence reported here could deeply change the current point of view concerning the role of ectopic calcifications in the progression of human diseases and also in the patients’ management. In fact, the presence of calcifications can suggest an unfavorable prognosis due to dysregulation of normal tissues homeostasis. 相似文献
32.
Qianyu Yang Chen Gao Xuemei Zhang Chihui Tsou Xingyu Zhao Manuel Reyes De Guzman Zejun Pu Xinyue Li Yue Lu Chunyan Zeng Li Yuan Yiqing Xia Yuping Sheng Yiqing Fu 《大分子材料与工程》2021,306(7):2100093
Hydrogels with excellent stiffness, toughness, anti-fatigue, and self-recovery properties are regarded as promising water-containing materials. In this work, a dual physically cross-linked (DPC) sodium alginate (SA)/poly[acrylamide (AAm)-acrylic acid (AAc)-octadecyl methacrylate (OMA)]-Fe3+ hydrogel is reported, which is constructed by hydrophobic association (HA) and ionic coordination (IC). The optimal DPC hydrogel demonstrates excellent mechanical performance: tensile modulus of 0.65 MPa, tensile strength of 3.31 MPa, elongation at break of 1547%, and toughness of 27.8 MJ m–3. SA/P(AAm-AAc-OMA)-Fe3+ DPC hydrogels also exhibit prominent anti-fatigue and self-recovery performance (99.1–109.7% modulus recovery and 90.4–108.9% dissipated energy recovery after resting for 5 min without additional stimuli at ambient temperature) through the reconstruction of reversible physical cross-linking. Some of the SA/P(AAm-AAc-OMA)-Fe3+ DPC hydrogels even exhibit a stretching-induced strengthening effect, which is similar to the performance of muscle—“the more training, the more strength.” Hence, the combination of HA and IC will provide an effective approach to design DPC hydrogels with desirable mechanical performances and a longer service life for wider applications of soft materials. 相似文献
33.
34.
Luis A. Pérez-Maqueda José Manuel Criado Concepción Real 《Journal of the American Ceramic Society》2002,85(4):763-768
A new method for the kinetic analysis of the initial stage of sintering for constant-heating-rate data has been proposed. Unlike all of the methods previously reported in the literature, this new method proposed here allows the simultaneous determination of the activation energy and the kinetic model from a single dilatometric curve recorded under a linear-heating-rate program. The proposed method has been tested with simulated sintering curves and experimental results have been obtained for the sintering of a rutile sample. 相似文献
35.
Manuel Belmonte Vitor A. Silva Antonio José Fernandes Florinda Costa Rui Silva 《Journal of the American Ceramic Society》2003,86(5):749-754
The efficiency of different surface pretreatments (four standard chemical etchings and four diamond powder abrasive procedures) on silicon nitride (Si3 N4 ) substrates for chemical vapor deposition (CVD) of diamond has been systematically investigated. Blank Si3 N4 samples were polished with colloidal silica (∼0.25 μm). Diamond nucleation and growth runs were conducted in a microwave plasma chemical vapor deposition apparatus for 10 min and 6 h, respectively. Superior results concerning nucleation density ( N d ∼ 1010 cm−2 after 10 min), film uniformity, and grain size (below 2 μm after 6 h) were obtained for the mechanically microflawed samples, revealing that chemical etchings (hot and cold strong acids, molten base or CF4 plasma) are not crucial for good CVD diamond quality on Si3 N4 . 相似文献
36.
Rana M. Tubaileh Antonio Garrido-Fernández M. Victoria Ruiz-Méndez Manuel León-Camacho Enrique Graciani-Constante 《Journal of the American Oil Chemists' Society》2002,79(1):101-104
Changes in the contents of waxes and fatty alcohols during deodorization/physical refining of bleached olive oil were studied.
Experiments were carried out with 1.85% acidity oil, which was physically refined in a discontinuous deodorizer of 250-kg
maximum capacity using nitrogen as stripping gas instead of steam. The variables studied were load and temperature of oil
in the deodorizer as well as N2 flow. Analyses of waxes and alcohols were carried out at different operation times. The maximum content of wax was always
observed when the oil reached the deodorization temperature. The variation in the wax content depended on temperature and
N2 flow. Wax decomposition started and continued during the operating time, and a progressive decrease, which was pronounced
between 3 and 4 h, was observed. Small changes in waxes were observed between 4 and 5 h. Total content of fatty alcohols diminished
throughout the operating time, and changes did not depend on the variables studied. 相似文献
37.
One of the leading time of flight imaging technologies for depth sensing is based on Photonic Mixer Devices (PMD). In PMD sensors each pixel samples the correlation between emitted and received light signals. Current PMD cameras compute eight correlation samples per pixel in four sequential stages to obtain depth with invariance to signal amplitude and offset variations. With motion, PMD pixels capture different depths at each stage. As a result, correlation samples are not coherent with a single depth, producing artifacts. We propose to detect and remove motion artifacts from a single frame taken by a PMD camera. The algorithm we propose is very fast, simple and can be easily included in camera hardware. We recover depth of each pixel by exploiting consistency of the correlation samples and local neighbors of the pixel. In addition, our method obtains the motion flow of occluding contours in the image from a single frame. The system has been validated in real scenes using a commercial low-cost PMD camera and high speed dynamics. In all cases our method produces accurate results and it highly reduces motion artifacts. 相似文献
38.
Poly(vinyl chloride)/wood fiber (flour) composites are currently experiencing a dramatic increase in use. Most of them are used to produce window/door profiles, decking, railing, and siding by using conical counterrotating intermeshing twin‐screw extruders. Heat stabilizers, processing aids, impact modifiers, lubricants, and pigments are still important for PVC/wood composite formulations. Poly[methylene(polyphenyl isocyanate)] (PMPPIC), γ‐aminopropyltriethoxysilane, maleated polypropylene (MAPP), and copper metallic complex have proved to be effective coupling agents for this composite system. Mechanical properties of PVC/wood composites can be enhanced by combining wood with mica or glass fibers to form hybrid reinforcements. Ultraviolet light resistance and weathering dimensional stabilities of PVC/wood composites are superior to those of natural wood. Density reduction can be achieved through the microcellular foaming technique by using chemical blowing agents, such as azodicarbonamide and sodium bicarbonate, or physical blowing agents, such as carbon dioxide. J. Vinyl Addit. Technol. 10:59–69, 2004. © 2004 Society of Plastics Engineers. 相似文献
39.
For heterogeneous distributed computing systems, important design issues are scalability and system optimization. Given such systems, it is crucial to develop low computational complexity algorithms to schedule tasks in a manner that exploits the heterogeneity of the resources and applications. In this paper, we report and evaluate three scalable, and fast scheduling heuristics for highly heterogeneous distributed computing systems. We conduct a comprehensive performance evaluation study using simulation. The benchmarking outlines the performance of the schedulers, representing scalability, makespan, flowtime, computational complexity, and memory utilization. The set of experimental results shows that our heuristics perform as good as the traditional approaches, for makespan and flowtime, while featuring lower complexity, lower running time, and lower used memory. The experimental results also detail the various scenarios under which certain algorithms excel and fail. 相似文献
40.