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1.
Maria Luisa Calabr Nayana Lazzari Giulia Rigotto Marco Tonello Antonio Sommariva 《International journal of molecular sciences》2020,21(23)
The mechanisms by which neoplastic cells disseminate from the primary tumor to metastatic sites, so-called metastatic organotropism, remain poorly understood. Epithelial–mesenchymal transition (EMT) plays a role in cancer development and progression by converting static epithelial cells into the migratory and microenvironment-interacting mesenchymal cells, and by the modulation of chemoresistance and stemness of tumor cells. Several findings highlight that pathways involved in EMT and its reverse process (mesenchymal–epithelial transition, MET), now collectively called epithelial–mesenchymal plasticity (EMP), play a role in peritoneal metastases. So far, the relevance of factors linked to EMP in a unique peritoneal malignancy such as pseudomyxoma peritonei (PMP) has not been fully elucidated. In this review, we focus on the role of epithelial–mesenchymal dynamics in the metastatic process involving mucinous neoplastic dissemination in the peritoneum. In particular, we discuss the role of expression profiles and phenotypic transitions found in PMP in light of the recent concept of EMP. A better understanding of EMP-associated mechanisms driving peritoneal metastasis will help to provide a more targeted approach for PMP patients selected for locoregional interventions involving cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. 相似文献
2.
In this paper, we investigate the best attainable performance for filtered multitone modulation (FMT) in time-variant frequency-selective fading channels when optimal maximum-likelihood (ML) detection is deployed. FMT generalizes the popular orthogonal frequency division multiplexing (OFDM) scheme through the deployment of subchannel shaping filters. The performance limits are derived by extending to this multichannel context the matched filter bounding technique. We first conduct an exact calculation for the average and the distribution of the matched filter error rate bound. Then, we follow a numerical procedure that overcomes the problems of accuracy and ill conditioning in the implementation of the exact method. This study allows for an analytical treatment of the diversity effect on performance as a function of the time/frequency selectivity of the channel. It is found that FMT is a diversity transform that is capable of yielding coding gains and time/frequency diversity gains as a function of the subcarrier spacing and the subchannel filter shape. 相似文献
3.
Botjan Brank Lamberto Briseghella Nicola Tonello Frano B. Damjani 《International journal for numerical methods in engineering》1998,42(3):409-442
Continuum and numerical formulations for non-linear dynamics of thin shells are presented in this work. An elastodynamic shell model is developed from the three-dimensional continuum by employing standard assumptions of the first-order shear-deformation theories. Motion of the shell-director is described by a singularity-free formulation based on the rotation vector. Temporal discretization is performed by an implicit, one-step, second-order accurate, time-integration scheme. In this work, an energy and momentum conserving algorithm, which exactly preserves the fundamental constants of the shell motion and guaranties unconditional algorithmic stability, is used. It may be regarded as a modification of the standard mid-point rule. Spatial discretization is based on the four-noded isoparametric element. Particular attention is devoted to the consistent linearization of the weak form of the initial boundary value problem discretized in time and space, in order to achieve a quadratic rate of asymptotic convergence typical for the Newton–Raphson based solution procedures. An unconditionally stable time finite element formulation suitable for the long-term dynamic computations of flexible shell-like structures, which may be undergoing large displacements, large rotations and large motions is therefore obtained. A set of numerical examples is presented to illustrate the present approach and the performance of the isoparametric four-noded shell finite element in conjunction with the implicit energy and momentum conserving time-integration algorithm. © 1998 John Wiley & Sons, Ltd. 相似文献
4.
E Nisoli E Clementi C Tonello C Sciorati L Briscini MO Carruba 《Canadian Metallurgical Quarterly》1998,125(4):888-894
1. In the present work, we study the effect of NO on the proliferation and differentiation of brown fat cells in primary cultures. 2. Brown fat precursor cells isolated from rat brown adipose tissue were cultured for 8 days until confluence and treated daily with the NO donating agents, S-nitroso-acetyl penicillamine (SNAP) or S-nitroso-L-glutathione (GSNO). Both agents (300 microM) decreased cell proliferation approximately 8 fold on day 8. The inhibitory effect of NO was unlikely to be due to cytotoxicity since (i) cells never completely lost their proliferation capacity even after 8 days of exposure to repeated additions of SNAP or GSNO, and (ii) the inhibitory effect was reversible after removal of the media containing NO donors. 3. Daily treatment with nitric oxide synthase inhibitors, such as NG-nitro-L-arginine methyl ester (L-NAME, 300 microM), led to the stimulation of cell proliferation by 44+/-5%, n=3, suggesting that NO, endogenously produced in brown adipocytes, may be involved in modulating cell growth. 4. Daily treatment with both SNAP or GSNO induced significant mitochondriogenesis, measured as the mitochondrial conversion of 3-[4,5-dimethylthiazol-2-yl-]-2,5-diphenyl tetrazolium bromide (MTT) to formazan, whilst daily treatment with L-NAME was without effect. 5. The inhibition of cell proliferation by NO donors was accompanied by the expression of two genes coding for peroxisome proliferator activated receptor-gamma and uncoupling protein-1, which are upregulated during differentiation. 6. Increasing cyclic GMP in cells by 8-bromo-cyclic GMP (100-1000 microM) did not reproduce the observed NO effects on either cell number or gene expression. On the other hand, chronic treatment with the inhibitor of the NO-stimulated guanylyl cyclase, 1H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one (ODQ), reduced the expression of peroxisome proliferator activated receptor-gamma and uncoupling protein-1. 相似文献
5.
In this letter we study filtered multitone modulation (FMT) for broadband multiuser power line communications. We address the implementation problem, and we derive a novel efficient digital implementation of both the synthesis and the analysis filter bank. A simple fractionally spaced multiuser receiver is also proposed. 相似文献
6.
High-Pressure Processing Technologies for the Pasteurization and Sterilization of Foods 总被引:2,自引:0,他引:2
Hugo M��jica-Paz Aurora Valdez-Fragoso Carole Tonello Samson Jorge Welti-Chanes J. Antonio Torres 《Food and Bioprocess Technology》2011,4(6):969-985
The food-processing industry has made large investments in processing facilities relying mostly on conventional thermal processing
technologies with well-established reliability and efficacy. Replacing them with one of the novel alternatives recently developed
is a decision that must be carefully approached. Among them, high-pressure processing (HPP), at room or refrigerated temperature,
is now a well-established option experiencing worldwide commercial growth. Surveys have shown an excellent consumer acceptance
of HPP technology. For financial feasibility reasons, HPP treatments must be kept short, a challenge that can be met by some
of the alternatives here reviewed such as the use of the hurdle technology concept. Although HPP technology is limited to
pasteurization treatments, the combination of high pressure and high temperature used in pressure-assisted thermal processing
(PATP) can be used to sterilize foods. An analysis of alternatives to achieve the inactivation of bacterial spores at the
lowest temperature possible highlights the need for additional research on the use of germinants. Because of incomplete research,
PATP presents several implementation challenges, including the modeling of food temperature, the determination of inactivation
kinetics particularly for bacterial spores, and the prediction of chemical changes including the potential formation of toxic
compounds. 相似文献
7.
Edmond Wai Yan So Matteo Munaro Stefano Michieletto Stefano Tonello Emanuele Menegatti 《Computers in Industry》2013
In this paper, we present a low-cost and highly configurable quality inspection system capable of capturing 2.5D color data, created using off-the-shelf machine vision components, open-source software libraries, and a combination of standard and novel algorithms for 2.5D data processing. The system uses laser triangulation to capture 3D depth, in parallel with a color camera and a line light projector to capture color texture, which are then combined into a color 2.5D model in real-time. 相似文献
8.
This article aims to address two aspects of lighting often treated intuitively by designers in charge of creating retail atmospheres, that is, the impact of color and light distribution, as design variables. The study comprised a controlled experiment with a repeated measure design with three directions of lighting (front, overhead, and wallwasher), as the within‐subject factor and four color combinations of the walls (yellow‐blue, magenta, gray, and green‐magenta), as the between‐group variable. The perceptual (visually) and emotional responses of 184 participants revealed the interplay between light and color on these psychological outcomes. Specifically, the results showed that the overhead direction of lighting improves the appearance of the less favored color conditions, either in terms of lack of visual complexity (monochromatic) or color itself (gray). In turn, the wallwasher lighting emphasized these attributes, differing according to visual or emotional aspects. In retailing, emotional dimensions such as activation and evaluation are desired, and they were confirmed across all the lighting and color conditions of this study. The results provide designers with certain perceptual cues regarding colors and their lighting mode to create desirable impressions and affect in retail spaces. 相似文献
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10.
In this letter, we propose two new Nyquist (intersymbol interference free) pulses that exhibit better error probability performance in the presence of sampling errors than the popular raised-cosine and a recently proposed pulse by Beaulieu, Tan, and Damen. The new pulses are also robust to the root and truncation operations. 相似文献