2D Optical CDMA Technique Dedicated to Multimedia transmission

International audienceIn this paper, we investigate the application of optical code division multiple access (OCDMA) to multimedia transmission (voice, data, video). The various services are differentiated by assigning to each user a specific two-dimensional (2D) code signature. The coding method used is adapted from 2D multi-wavelength optical orthogonal codes (MWOOC). We first generate 2D multi-weight codes to differentiate the quality of service (QoS). Then, by applying a parallel mapping technique, we achieve multi-rate services. The theoretical error probability corresponding to the quality of each service is established in the noiseless case. This permits evaluating the potentiality of such systems in terms of number of communicating users and data rates. This study has been realized considering a conventional correlation receiver (CCR) with and without hard limiting (HL) device

2-Dimensional Optical CDMA system performances with Parallel Interference Cancellation

International audienceIn this paper, we investigate the feasibility of a 2-Dimensional Optical Code Division Multiple Access (2D-OCDMA) system, with electronic coding and decoding functions. We develop a modified construction method of Multi-Wavelength Optical Orthogonal Codes (MWOOC) that permits high flexibility in the code parameters choice. The 2D code performance is calculated for a Conventional Correlation Receiver (CCR) and a more complex one, named Parallel Interference Cancellation (PIC) receiver. For example, for a Bit Error Rate (BER) =<10^-^9, and 30 simultaneous users, we show that contrary to the CCR, the use of a PIC receiver leads to workable 2D electric coding solutions

Optimal code design for multi wavelength OOC optical CDMA systems

International audienceThe objective of this work is to design optimal codes for a 2 Dimensional Optical Code Division Multiple Access system (2D-OCDMA), and to test their robustness to noise perturbation. 2D coding is performed by Multi-Wavelength Optical Orthogonal Codes (MWOOC). They are obtained with our new construction method which permits to choose the code parameters with high flexibility. Different receiver structures are studied: a Conventional Correlation Receiver (CCR), and a Parallel Interference Cancellation receiver (PIC). For each structure, the optimal code parameters are evaluated, in order to obtain a Bit Error Rate (BER) 10-9, for 30 active users, with a minimal temporal code length, and a minimal number of wavelengths. Finally, we show that, compared to the CCR, the PIC receiver permits to reduce the temporal code length and the number of wavelength, and that it also permits to reduce the required SNR for noisy signal

2-Dimensionnal code design for an optical CDMA system with parallel interference cancellation receiver

International audienceThe objective of this paper is to design a two-Dimensional Optical Code Division Multiple Access system (2D-OCDMA) for application in access networks, with coding and decoding functions performed by electronic devices. We present a new construction method of Multi-Wavelength Optical Orthogonal Codes (MWOOC), which permits a high flexibility in the code parameters choice. This work evaluates in the noiseless case, the MWOOC potentialities for two receiver structures: a Conventional Correlation Receiver (CCR) and a Parallel Interference Cancellation receiver (PIC). We show that with a PIC receiver, it is possible to design two-Dimensional codes that respect the access specification

Inventory of armourstone

Natural armourstone is widely used for hydraulic works, both in the coastal domain and in border of rivers and torrents, especially to protect against flood and the effects of waves and currents. To meet the expectations associated with this resource, an inventory of armourstone quarries was realized on a national scale in France. This inventory informs not only about the localization of quarries but also about the quality and the availability of materials. To fully optimize this inventory in a dynamic format, the association of all actors of the sector was preferred to archival research. This partnership approach led to project deliverables that can constitute durably a shared reference. The database can indeed be updated regularly thanks to the contacts established with the professionals of quarries. The access to this database is offered to a wide public: maritime and fluvial ports, local authorities in charge of planning and managing structures that protect against flood and other hydraulic hazards. This new database was organized considering its importance on the operational plan. This led to a hierarchical organization at two levels for each quarry face: first level, a synthesis sheet brings the essential information to realize choices upstream to the operational phases. Second level, a detailed specification sheet presents the technical characteristics observed in the past on the considered face. The atlas has two information broadcasting formats: a pdf file with browsing functions and a geographical information system that allows remote request of the database. These two media have their own updating rhythms, annual for the first and continue for the second

Inventory of armourstone

Natural armourstone is widely used for hydraulic works, both in the coastal domain and in border of rivers and torrents, especially to protect against flood and the effects of waves and currents. To meet the expectations associated with this resource, an inventory of armourstone quarries was realized on a national scale in France. This inventory informs not only about the localization of quarries but also about the quality and the availability of materials. To fully optimize this inventory in a dynamic format, the association of all actors of the sector was preferred to archival research. This partnership approach led to project deliverables that can constitute durably a shared reference. The database can indeed be updated regularly thanks to the contacts established with the professionals of quarries. The access to this database is offered to a wide public: maritime and fluvial ports, local authorities in charge of planning and managing structures that protect against flood and other hydraulic hazards. This new database was organized considering its importance on the operational plan. This led to a hierarchical organization at two levels for each quarry face: first level, a synthesis sheet brings the essential information to realize choices upstream to the operational phases. Second level, a detailed specification sheet presents the technical characteristics observed in the past on the considered face. The atlas has two information broadcasting formats: a pdf file with browsing functions and a geographical information system that allows remote request of the database. These two media have their own updating rhythms, annual for the first and continue for the second

Clonal Dynamics of FLT3 -ITD Positive Acute Myeloid Leukemia Patients with Relapsed/Refractory Disease Following Intensive Chemotherapy +/- Midostaurin

International audienceIntroduction: Despite the wider use of midostaurin (MIDO) in combination with intensive chemotherapy (ICT) as the 1st-line treatment for FLT3-mutated acute myeloid leukemia (AML), complete remission (CR) rates are close to 60%, and relapses occur in over 40% of cases, demonstrating the ability of leukemic cells to resist and evade therapy ( Stone et al., NEJM 2017). Conventional fragment-length analyses of paired diagnosis/relapse samples have shown that FLT3-internal tandem duplications (ITDs) are retained in 80% and 50% of cases following ICT alone and MIDO+ICT respectively ( Schmalbrock et al., Blood 2021). Only limited data are available on the dynamics of FLT3-ITDs or other co-mutations in refractory patients (pts). Here, we conducted a retrospective study involving 115 pts with relapsed/refractory AML harboring FLT3-ITD at diagnosis. Materials and methods: Clonal evolution was examined in paired diagnosis/progression blood or bone marrow samples from 115 pts with FLT3-ITD+ AML treated with MIDO+ICT (n=33) or ICT alone (n=82). Among them, 21 pts had primary refractory disease (MIDO+ICT, n=8; ICT, n=13) and 94 pts relapsed after achieving CR (MIDO+ICT, n=25; ICT, n=69). FLT3-ITDs and co-mutations were screened on genomic DNA by high-throughput sequencing at both timepoints using a custom-designed panel. For accurate annotation and quantification of FLT3-ITDs from sequencing data, we used the recentlypublished FiLT3r algorithm ( Boudry et al., BMC Bioinformatics 2022). For each ITD detected, FiLT3r allelic ratio (AR) was assessed by the ratio between the mutated allele and the wild-type allele. Results: A total of 226 FLT3-ITDs were detected in 115 pts at AML diagnosis, among which 120 (53%) ITDs were found with an AR below 0.05 ( Figure 1). Among pts who achieved CR and experienced relapse (n=94), 48 had multiple FLT3-ITDs at diagnosis and 46 had a single FLT3-ITD at diagnosis. Overall, we observed a simplification of the FLT3-ITD repertoire upon relapse with the persistence of at least one initial clone in 8/12 [67%] and 24/36 [67%] pts with multiple ITDs receiving MIDO+ICT and ICT alone respectively. In relapsed pts who initially had a single FLT3-ITD clone at diagnosis, the addition of MIDO to ICT was associated with a higher rate of FLT3-ITD negativity compared to pts receiving ICT alone (6/13 [46%] vs 5/33 [15%]; P = 0.05) ( Figure 2). Interestingly, among 21 pts with primary refractory AML, we observed that FLT3-ITD mutation status became negative in 5/8 pts (62%) and 2/13 pts (15%) after induction with MIDO+ICT and ICT alone respectively. We then compared the initial characteristics between retained and lost FLT3-ITDs at AML relapse. Lost FLT3-ITDs had significantly lower AR than retained clones in both treatment groups. In order to limit the impact of sample dilution on the allele burden, we defined adjusted variant allele frequencies (VAFs) as the VAFs of FLT3-ITDs normalized to the VAFs of NPM1 mutations, whenever applicable. In so doing, we observed that adjusted VAFs of retained FLT3-ITDs increased at relapse, regardless of the treatment group (adjusted VAF, diagnosis vs relapse: 0.28 vs 0.86 and 0.88 vs 1.6 in the MIDO+ICT group and ICT alone group; P = 2.3e-03 and P = 2.4e-04). Importantly, an adjusted VAF higher than 1 was strongly suggestive of a homozygous state of FLT3-ITD. Such situation was found to be more prevalent at relapse in both treatment groups. Besides the selection of a dominant FLT3-ITD clone, other relapse-related changes including the acquisition of additional mutations will be presented. Conclusion: Our study of the clonal dynamics of AML with FLT3-ITD mutations provides insights into the mechanisms underlying therapy escape. Our data suggest that clonal interference characterized by multiple FLT3-ITD clones is associated with a greater ability to select a FLT3-ITD-positive clone at relapse in pts receiving MIDO+ICT. Although the addition of MIDO to ICT increases the probability of eradicating a single FLT3-ITD clone, FLT3-ITD+ relapses remain common following this combination, often with the selection of homozygous FLT3-ITD clones and/or the emergence of new mutations. Finally, our data in refractory situation emphasize the need to reassess mutational status at each stage of progression before implementing targeted therapy