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81.
An infostation is an isolated pocket area, with small coverage of high bandwidth connectivity, which collects information requests of mobile users and delivers data while users are going through the coverage area. In this paper, the performance of infostations networks with single, double and triple frequencies is studied. The two-slope propagation loss model is used to calculate the signal-to-interference plus noise ratio. The effect of the propagation parameters on the infostation performance is studied. 相似文献
82.
Miguel A. Otaduy Rasmus Tamstorf Denis Steinemann Markus Gross 《Computer Graphics Forum》2009,28(2):559-568
We present an algorithm for robust and efficient contact handling of deformable objects. By being aware of the internal dynamics of the colliding objects, our algorithm provides smooth rolling and sliding, stable stacking, robust impact handling, and seamless coupling of heterogeneous objects, all in a unified manner. We achieve dynamicsawareness through a constrained dynamics formulation with implicit complementarity constraints, and we present two major contributions that enable an efficient solution of the constrained dynamics problem: a time stepping algorithm that robustly ensures non-penetration and progressively refines the formulation of constrained dynamics, and a new solver for large mixed linear complementarity problems, based on iterative constraint anticipation. We show the application of our algorithm in challenging scenarios such as multi-layered cloth moving at high velocities, or colliding deformable solids simulated with large time steps. 相似文献
83.
Miguel-González Celia García-Díaz Manuel Pereiras Bruno Vigil Miguel Rodríguez de Castro Alejandro 《Journal of Mechanical Science and Technology》2021,35(7):2929-2938
Journal of Mechanical Science and Technology - The present study focuses on the numerical modelling of gas-jet wiping process. Many processes involving liquids are necessary during steel... 相似文献
84.
Cleomacio Miguel da Silva Carlos Eduardo de Oliveira Costa Júnior 《The International journal of environmental studies》2019,76(3):357-369
The counties of Pedra and Venturosa have one of the largest natural radioactive occurrences of Brazil. The large farms producing milk in the state of Pernambuco are located in these counties. The forage plants cultivated on those farms have high concentrations of 228Ra, a naturally occurring descending radionuclide from the 232Th series. The 228Ra is transferred to the forage plants, and once ingested by the lactating cow, this radionuclide is rapidly transferred to the milk. Thus, milk intake is an important route for 228Ra of incorporation by the human consumer and may induce the appearance of bone sarcoma. Accordingly, the aim of the present study was to determine the concentrations of 228Ra in milk produced in the Pedra and Venturosa farms, in order to estimate the risk of ingestion in the local population. The 228Ra was determined by actin-228 (228Ac) using the radiochemical technique of barium sulphate precipitate (BaSO4). The milk samples had concentrations of 228Ra ranging from 61 to 1338 mBq.l?1, which corresponded to the cumulative equivalent dose ranging from 0.04 to 0.1 Sv. Although the doses were low, regulatory and protective measures should be taken to study the radiotoxic effects of 228Ra in subjects in the public. 相似文献
85.
Juan Manuel Enrique Jos Manuel Andújar Eladio Durn Miguel Angel Martínez 《Progress in Photovoltaics: Research and Applications》2015,23(12):1940-1955
This paper presents a new, simple, accurate, and inexpensive practical methodology and experimental solution for the modeling of conventional (domestic and commercial facilities) photovoltaic generators (PVG), so that they can work at their maximum power point (MPP). The PVG may be a panel, an array of panels, or a photovoltaic field. As a starting restriction (actual) it has to be assumed that it is not possible to isolate the PVG variables dependence (mainly current, voltage, and hence power) with solar radiation and temperature, because they are highly correlated. This methodology proposes the modeling facility on its MPP by its MPP resistance (RMPP = VMPP/IMPP), being VMPP and IMPP the voltage and current of the PVG, respectively, at its MPP. The analysis shows, by simulation first and then experimentally, that RMPP does not present significant temperature dependencies, at least in the usual range. This important result allows us to model the PVG only in terms of solar radiation. From a set of experimental data, different models to estimate RMPP are proposed. The obtained results are very accurate. These models allow an immediate practical application that it is also developed in the paper: MPP tracker (MPPT) design by the calculation of the DC/DC converter duty cycle which places the PVG at its MPP directly and continuously. This new methodology and experimental system has been registered in the Spanish Patent and Trademark Office with the number P201530352. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
86.
Miguel A. Otero María del C. Vasallo Olga Verdecia Víctor Fernndez Dionisio Betancourt 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1996,67(1):67-71
A process for the preparation of yeast-derived food additives was developed. The four products obtained, yeast protein concentrate (YPC), cell-wall protein (CWP), semi-pure glucomannan (SPG) and yeast extract, compared well with similar products, present in the current market, with respect to functional properties. YPC and CWP exhibited improved water-holding and oil-binding properties over those of soy-protein isolate (SPI). The emulsifying capacity was very close to that observed in commercial samples. A one-step alkaline extraction enhanced the functional properties of primary yeast glycan to match traditional food hydrocolloid sources. SPG showed oil-binding properties significantly greater than commercial glucomannan. 相似文献
87.
Lucía Monteoliva Miguel Snchez Jesús Pla Concha Gil Csar Nombela 《Yeast (Chichester, England)》1996,12(11):1097-1105
The yeast SEC14 gene product is required for the transport of proteins from the Golgi complex. We have cloned the homologous Candida albicans SEC14 gene (CaSEC14) by functional complementation of a Saccharomyces cerevisiae thermosensitive mutant, sec14. Some putative TATA boxes have been identified in CaSEC14 and, contrary to S. cerevisiae SEC14, no introns were found in the Candida homologue. Sequence analysis revealed that CaSec14p is a 301 amino acid protein, 67% identical to S. cerevisiae and Kluyveromyces lactis Sec14p, and 61% identical to the 300 amino-terminal residues of Yarrowia lipolytica Sec14p. Hydrophatic profile analysis of CaSec14p suggests a soluble protein without transmembrane domains, as has been described for the S. cerevisiae counterpart. While it was easy to disrupt one allele of SEC14 in C. albicans, repeated attempts to disrupt the second allele were unsuccessful, thus suggesting that the gene could be essential for vegetative growth in C. albicans. The sequence has been deposited in the EMBL data library under Accession Number X81937. 相似文献
88.
Maria Sofia Vieira-Rocha Pilar Rodriguez-Rodriguez Mariana Ferreira-Duarte Miguel Faria Joana Beatriz Sousa Manuela Morato Silvia Magdalena Arribas Carmen Diniz 《International journal of molecular sciences》2022,23(3)
Fetal stress is known to increase susceptibility to cardiometabolic diseases and hypertension in adult age in a process known as fetal programming. This study investigated the relationship between vascular RAS, oxidative damage and remodeling in fetal programming. Six-month old Sprague-Dawley offspring from mothers that were fed ad libitum (CONTROL) or with 50% intake during the second half of gestation (maternal undernutrition, MUN) were used. qPCR or immunohistochemistry were used to obtain the expression of receptors and enzymes. Plasma levels of carbonyls were measured by spectrophotometry. In mesenteric arteries from MUN rats we detected an upregulation of ACE, ACE2, AT1 receptors and NADPH oxidase, and lower expression of AT2, Mas and MrgD receptors compared to CONTROL. Systolic and diastolic blood pressure and plasma levels of carbonyls were higher in MUN than in CONTROL. Vascular morphology evidenced an increased media/lumen ratio and adventitia/lumen ratio, and more connective tissue in MUN compared to CONTROL. In conclusion, fetal undernutrition indices RAS alterations and oxidative damage which may contribute to the remodeling of mesenteric arteries, and increase the risk of adverse cardiovascular events and hypertension. 相似文献
89.
90.
Catarina Almeida-Ferreira Rafael Silva-Teixeira Ana Cristina Gonalves Carlos Miguel Marto Ana Bela Sarmento-Ribeiro Francisco Caramelo Maria Filomena Botelho Mafalda Laranjo 《International journal of molecular sciences》2022,23(3)
Breast cancer (BC) is a malignant neoplasia with the highest incidence and mortality rates in women worldwide. Currently, therapies include surgery, radiotherapy, and chemotherapy, including targeted therapies in some cases. However, treatments are often associated with serious adverse effects. Looking for new options in BC treatment, we evaluated the therapeutic potential of cold atmospheric plasma (CAP) in two cell lines (MCF7 and HCC1806) with distinct histological features. Apoptosis seemed to be the most prevalent type of death, as corroborated by several biochemical features, including phosphatidylserine exposure, the disruption of mitochondrial membrane potential, an increase in BAX/BCL2 ratio and procaspase 3 loss. Moreover, the accumulation of cells in the G2/M phase of the cell cycle points to the loss of replication ability and decreased survival. Despite reported toxic concentrations of peroxides in culture media exposed to plasma, intracellular peroxide concentration was overall decreased accompanying a reduction in GSH levels shortly after plasma exposure in both cell lines. In HCC1806, elevated nitric oxide (NO) concentration accompanied by reduced superoxide levels suggests that these cells are capable of converting plasma-derived nitrites into NO that competes with superoxide dismutase (SOD) for superoxide to form peroxinitrite. The concomitant inhibition of the antioxidative activity of cells during CAP treatment, particularly the inhibition of cytochrome c oxidase with sodium azide, synergistically increased plasma toxicity. Thus, this in vitro research enlightens the therapeutic potential of CAP in the treatment of breast cancer, elucidating its possible mechanisms of action. 相似文献