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271.
272.
Armando Soares Nuno Souto João C. Silva Patrícia Eusébio Américo Correia 《Wireless Personal Communications》2007,42(2):185-211
Broadcast and multicast offer a significant improvement of spectrum utilization, and becomes particularly important where
information channels are shared among several users. Mobile cellular environments are expected to evolve with the technological
approaches necessary to facilitate the deployment of multimedia services, such as streaming, file download and carousel services.
The perspective that video streaming in wireless networks services is an attractive service to end-users has spurred the research
in this area. To provide for a video delivery platform in UMTS, the Third Generation Partnership Project (3GPP) addressed
this problem with the introduction of the Multimedia Broadcast and Multicast Services (MBMS) in 3GPP Release 6. In this document
we analyse several effective radio resource management techniques to provide MBMS, namely, use of non-uniform QAM constellations,
multi-code and macro-diversity to guarantee the optimal distribution of QoS depending on the location of mobiles. 相似文献
273.
Incorporation of sunscreens into lipid carriers with an increased sun protection factor (SPF) has not yet been fully accomplished. In the present paper, the effectiveness of a sunscreen mixture, incorporated into the novel topical delivery systems, i.e. solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC), used as ultraviolet (UV) protector enhancers with a distinctly higher loading capacity has been developed and evaluated. SLN and NLC were produced by hot high pressure homogenization technique in lab scale production. Size distribution and storage stability of formulations were investigated by laser diffractometry and photon correlation spectroscopy. Nanoparticles were characterized by their melting and recrystallization behaviour recorded by differential scanning calorimetry. Lipid nanoparticles produced with a solid matrix (SLN and NLC) were established as a UV protection system. The loading capacities for molecular sunscreens reported before now were in the range of 10-15%. It was possible to load NLC with up to 70% with molecular sunscreen, which is appropriate to obtain high SPFs with this novel UV protection system. The developed formulations provide a beneficial alternative to conventional sunscreen formulations. The UV protective efficacy of the lipid particles varied with the nature of lipid and UV wavelength. 相似文献
274.
Elida Fernanda Xavier Julio ;Simplicio Amaud da Silva ;Cicero da Rocha Souto ;Isaac Soares de Freitas 《机械工程与自动化:英文版》2014,(6):511-520
In this paper, it presents a project of a fuzzy controller and a neural estimator to control a coordinate table powered by three-phase induction motor, aiming to implement an intelligent milling system. The position/speed control is performed using vector techniques of three-phase induction machines. The estimation of the motor electromagnetic torque is used for setting the feedrate of the table. The speed control is developed using TS (Takagi-Sugeno) fuzzy logic model and electromagnetic torque estimation using neural network type LMS (least mean square) algorithm. The induction motor is powered by a frequency inverter driven by a DSP (digital signal processor). Control strategies are implemented in DSP. Simulation results are presented for evaluating the performance of the system. 相似文献
275.
Clare Murray Eva Galvan Carlos Ontiveros Yilun Deng Haiyan Bai Alvaro Souto Padron Kathryn Hinchee-Rodriguez Myrna G. Garcia Anand Kornepati Jose Conejo-Garcia Tyler J. Curiel 《International journal of molecular sciences》2022,23(9)
The interaction between tumor surface-expressed PDL1 and immune cell PD1 for the evasion of antitumor immunity is well established and is targeted by FDA-approved anti-PDL1 and anti-PD1 antibodies. Nonetheless, recent studies highlight the immunopathogenicity of tumor-intrinsic PDL1 signals that can contribute to the resistance to targeted small molecules, cytotoxic chemotherapy, and αPD1 immunotherapy. As genetic PDL1 depletion is not currently clinically tractable, we screened FDA-approved drugs to identify those that significantly deplete tumor PDL1. Among the candidates, we identified the β-lactam cephalosporin antibiotic cefepime as a tumor PDL1-depleting drug (PDD) that increases tumor DNA damage and sensitivity to DNA-damaging agents in vitro in distinct aggressive mouse and human cancer lines, including glioblastoma multiforme, ovarian cancer, bladder cancer, and melanoma. Cefepime reduced tumor PDL1 post-translationally through ubiquitination, improved DNA-damaging-agent treatment efficacy in vivo in immune-deficient and -proficient mice, activated immunogenic tumor STING signals, and phenocopied specific genetic PDL1 depletion effects. The β-lactam ring and its antibiotic properties did not appear contributory to PDL1 depletion or to these treatment effects, and the related cephalosporin ceftazidime produced similar effects. Our findings highlight the rapidly translated potential for PDDs to inhibit tumor-intrinsic PDL1 signals and improve DNA-damaging agents and immunotherapy efficacy. 相似文献
276.
Roberto Pinto Souto Carla Osthoff Douglas Augusto Oswaldo Trelles Ana Tereza Ribeiro de Vasconcelos 《通讯和计算机》2013,(12):1522-1528
High-density oligonucleotide microarrays allow several millions of genetic markers in a single experiment to be observed. Current bioinformatics tools for gene-expression quantile data normalization are unable to process such huge data sets. In parallel with this reality, the huge volume of molecular data produced by current high-throughput technologies in modern molecular biology has increased at a similar pace, challenging our capacity to process and understand data. On the other hand, the arrival of CUDA (compute unified device architecture) has unveiled the extraordinary power of GPUs (graphics processing units) to accelerate data intensive general purpose computing more and more as time goes by. In this work, we have evaluated the use of dynamic parallelism for ordering gene-expression data, where the management of kernels launching can be done not only by the host, but also by the device. Each sample has more than 6.5 million genes. We optimized the Quicksort parallel implementation available in the CUDA-5.5 Toolkit Samples and compared the performance of the sequential Quicksort algorithm from the GNU C Library (glibc) and with the parallel radix sort implementation available in the CUDPP-2.1 library. The Quicksort parallel implementation is designed to run on the GPU Kepler architecture, which supports dynamic parallelism. The results show that in the studied application the GPU parallel version with dynamic parallelism attains speed-ups in the data-sorting step. However, to achieve an effective overall speed-up considering the radix sort algorithm, performance of the whole application needs further optimizations. 相似文献
277.
Silicon - In this work, we propose a Germanium Fin Buried Oxide (FinBOX) Fin Electron-Hole Bilayer Tunnel FET (FBF-EHBTFET) structure. The proposed structure eliminates the gated underlaps and... 相似文献
278.
Silicon - In this paper, we propose, design and simulate a new double gate (DG) tunnel field effect transistor (TFET), using germanium (Ge) source, dual dielectric gate oxide, gate/drain underlap... 相似文献
279.
Manuela Carvalho Baptista Hesham Khalifa Adão Araújo Beatriz Arouca Maia Manuel Souto Maria Helena Braga 《Advanced functional materials》2023,33(10):2212344
The advent of new solid-state energy storage devices to tackle the electrical revolution requires the usage of nonlinear behavior leading to emergent phenomena. The ferroelectric analyzed herein belongs to a family of electrolytes that allow energy harvesting and storage as part of its self-charging features when thermally activated. The Na2.99Ba0.005ClO electrolyte shows quasi-adiabatic behavior with a continuous increase in polarization upon cycling, displaying almost no hysteresis. The maximum polarization obtained at a weak electric field is giant and similar to the remanent polarization. It depends on the temperature with a pyroelectric coefficient of 5.37 C m−2 °C−1 from −5 to 46 °C. The emergence occurs via negative resistance and capacitance. The glass transition is found to have its origins in the sharp depolarization at 46 – 48 °C. Above –10 °C, at ≈ –5 °C, another thermal anomaly may rely on the topologic characteristics of the A3–2xBaxClO (A = Li, Na, K) glass electrolytes enabling positive feedback of the current of electrons throughout the surface of the inner cell. The phenomena may pave the way toward a better understanding of dipolar nanodomain fragile glasses with exceptional ferroelectric characteristics to architect energy harvesting and storage devices based on multivalent thermally activated Na+-ion-ion electrolytes. 相似文献