Tumor microenvironment models: ex vivo, in vitro and in silico approaches to address targeted therapies

"Cancer is the second leading cause of mortality worldwide, despite the extraordinary advances in the last two decades due to the development of targeted therapies. These target particular molecules required for cell growth and tumorigenesis; nonetheless, de novo or acquired resistance to therapy often lead to patient relapse and disease progression. There is cumulating evidence supporting the importance of tumor microenvironment (TME)-driven mechanisms in cancer progression and drug resistance. Therefore, there is a need for cancer models in which critical components of the TME, such as the non-malignant cell types and the extracellular matrix (ECM), are represented and tissue architecture is maintained. (...)"N/

On the use of the Gaussian approach for the performance evaluation of direct-detection OFDM receivers impaired by in-band crosstalk

The Gaussian approach (GA) is used to assess the impact of in-band crosstalk on the performance of direct-detection orthogonal frequency division multiplexing (OFDM) optical communication systems. The GA accuracy is compared with estimates of the bit error probability (BEP) and crosstalk penalty obtained using Monte Carlo (MC) simulation. The GA revealed a reduced accuracy when estimating the BEP. However, when estimating the 1 dB crosstalk penalty, the GA exhibited a good accuracy (less than 0.5 dB in comparison with the crosstalk level estimated using MC simulation), for 16-quadrature amplitude modulation (QAM) and 64-QAM mappings in the OFDM subcarriers. The GA leads to very discrepant estimates of the crosstalk penalty for high crosstalk levels.info:eu-repo/semantics/acceptedVersio

Moment Generating Function for the Rigorous Performance Assessment of Direct-Detection Baseband OFDM Communication Systems

WOS:000312036100008 (Nº de Acesso Web of Science)“Prémio Científico ISCTE-IUL 2013”A new moment generating function (MGF) is proposed to assess rigorously the performance of optically preamplified receivers with direct-detection employing baseband orthogonal frequency division multiplexing (OFDM). By comparison with Monte Carlo simulation, the proposed MGF-based method shows very good accuracy when predicting the bit error probability for arbitrary optical and electrical filters, different numbers of OFDM subcarriers, and double sideband and single sideband optical OFDM signals. Its good accuracy when estimating the bit error probability in each individual subcarrier is also demonstrated. The new MGF-based method exhibits a significant improvement of accuracy when compared to the MGF-based method previously reported in the literature, especially for filter bandwidths not exceeding the OFDM signal bandwidth, which is the range corresponding to the optimum filter bandwidth

Influence of the SSBI mitigation on the in-band crosstalk tolerance of virtual carrier-assisted DD multi-band OFDM metro networks

In this work, the tolerance to in-band crosstalk of virtual carrier (VC)-assisted direct detection (DD) multi-band orthogonal frequency division multiplexing (MB-OFDM) metro networks, with and without signal-to-signal beat interference (SSBI) mitigation, is compared numerically for 4-ary, 16-ary and 64-ary quadrature amplitude modulation (QAM) formats in the OFDM subcarriers. Our results show that the tolerance to in-band crosstalk is improved for lower modulation format orders. The tolerance to in-band crosstalk of DD OFDM receivers considering 4-QAM modulation format at the DD OFDM subcarriers is above 14 dB higher than the one obtained for the 64-QAM modulation format, regardless the receiver configuration. We have also shown that, the tolerance to in-band crosstalk for a given modulation format order depends on the difference between the virtual carrier-to-band power ratio (VBPR) of the selected and interfering signals, as interferers with same VBPR as the selected signal leads to equal tolerance to in-band crosstalk, independently from the DD OFDM receiver configuration and the subcarrier modulation format order considered.info:eu-repo/semantics/acceptedVersio

Transmission of CPRI signals along weakly-coupled multicore fibers for support of 5G networks

The impact of intercore crosstalk (ICXT) of weakly-coupled multicore fibers on the transmission performance of a Common Public Radio Interface (CPRI) signal in 5G networks is studied by numerical simulation. The results show that forward error correction-supported CPRI signals (accepting higher bit error rates) have more tolerance to ICXT, which increases with the skew between cores. Improvement of the tolerance of CPRI signals to the ICXT, due to the increase of the skew, by 1.7 dB is shown.info:eu-repo/semantics/publishedVersio

Tolerance to in-band crosstalk of virtual carrier-assisted direct detection multi-band OFDM system

The tolerance to in-band crosstalk of virtual carrier (VC)-assisted direct detection (DD) multi-band orthogonal frequency division multiplexing (MB-OFDM) system is assessed numerically through Monte-Carlo simulation and considering a single interferer. The influence of the virtual carrier-to-band power ratio (VBPR) and the virtual carrier-to-band gap (VBG) of the interferer on the in-band tolerance is also studied. We show that, for interferers with the same VBG as the selected signal, the increase of the VBPR of the interferer leads to lower optical signal-to-noise ratio (OSNR) penalties. The increase of the VBG of the interferer with central frequency different from the selected signal also leads to lower OSNR penalties. When the central frequencies of the interferer and selected bands are the same, the variation VBG of the interferer can lead to 11 dB less tolerance to in-band crosstalk of the VC-assisted DD OFDM system.info:eu-repo/semantics/acceptedVersio

Assessment of the combined effect of laser phase noise and intercore crosstalk on the outage probability of DD OOK Systems

We study the influence of the combined effect of laser phase noise and intercore crosstalk on the outage probability of direct-detection 10 Gbit/s on-off keying optical communication systems. We show that the laser phase noise can affect significantly the outage probability, for lasers with linewidths in the MHz range, for low and high skew-bit rate products. We also show that the laser phase noise effect on the received eye-pattern is qualitatively similar to the one found for high skew-bit rate product in the absence of laser phase noise.info:eu-repo/semantics/acceptedVersio

Inter-core crosstalk dependence on design parameters in coherent detection weakly-coupled multicore fiber systems

We assess, through numerical simulation, the dependence of the variance of the inter-core crosstalk (ICXT) and the maximum allowable ICXT level on the design parameters of coherent detection MCF systems. The analysed design parameters are the order of the quadrature amplitude modulation (QAM) signals, roll-off factor, time misalignment between the signal in different cores and skew between cores. The results show that, when the roll-off factor is 0, the maximum allowable ICXT level is independent of the skew and decreases for higher QAM orders. For a roll-off factor of 1, the maximum allowable ICXT level depends on the skew and time misalignment of core signals. In this case, the maximum allowable ICXT level increases by 3.6 dB relative to the case of roll-off factor of 0 with null skew, and by 2 dB, when the skew is much higher than the symbol period.info:eu-repo/semantics/acceptedVersio

Characterization of crosstalk-impaired OOK signals in WC-MCF systems with high and low skew×bit rate

The received amplitudes of crosstalk-impaired on-off keying signals in weakly-coupled multicore fibre (WC-MCF) systems are experimentally assessed for high and low skew×bit-rate. Gaussian-distributed crosstalk-induced amplitudes are shown for high skew×bit-rate. The mean of these amplitudes can also be modelled by Gaussian distributions.info:eu-repo/semantics/acceptedVersio