Signal Design and Machine Learning Assisted Nonlinearity Compensation for Coherent Optical Fibre Communication Links

This thesis investigates low-complexity digital signal processing (DSP) for signal design and nonlinearity compensation strategies to improve the performance of single-mode optical fibre links over different distance scales. The performance of a novel ML-assisted inverse regular perturbation technique that mitigates fibre nonlinearities was investigated numerically with a dual-polarization 64 quadrature amplitude modulation (QAM) link over 800 km distance. The model outperformed the heuristically-optimised digital backpropagation approach with <5 steps per span and mitigated the gain expansion issue, which limits the accuracy of an untrained model when the balance between the nonlinear and linear components becomes considerable. For short reach links, the phase noise due to low-cost, high-linewidth lasers is a more significant channel impairment. A novel constellation optimisation algorithm was, therefore, proposed to design modulation formats that are robust against both additive white Gaussian noise (AWGN) and the residual laser phase noise (i.e., after carrier phase estimation). Subsequently, these constellations were numerically validated in the context of a 400ZR standard system, and achieved up to 1.2 dB gains in comparison with the modulation formats which were optimised only for the AWGN channel. The thesis concludes by examining a joint strategy to modulate and demodulate signals in a partially-coherent AWGN (PCAWGN) channel. With a low-complexity PCAWGN demapper, 8- to 64-ary modulation formats were designed and validated through numerical simulations. The bit-wise achievable information rates (AIR) and post forward error correction (FEC) bit error rates (BER) of the designed constellations were numerically validated with: the theoretically optimum, Euclidean (conventional), and low-complexity PCAWGN demappers. The resulting constellations demonstrated post-FEC BER shaping gains of up to 2.59 dB and 2.19 dB versus uniform 64 QAM and 64-ary constellations shaped for the purely AWGN channel model, respectively. The described geometric shaping strategies can be used to either relax linewidth and/or carrier phase estimator requirements, or to increase signal-to-noise ratio (SNR) tolerance of a system in the presence of residual phase noise

Little evidence for fast mapping in adults with developmental amnesia.

Cooper, Greve, and Henson (this issue) conclude that hippocampal-independent learning, as operationalised by 'fast mapping' (FM), is unlikely to facilitate learning in adults. We provide evidence from patients with Developmental Amnesia (DA), who acquire language and semantic knowledge despite early hippocampal pathology. We administered an FM paradigm to three patients with DA and controls. Patients showed no benefit of FM compared to explicit encoding. These data support the conclusion that FM is unlikely to facilitate learning in amnesia, regardless of age at onset. Hippocampal-independent learning may be possible in adults with DA, but such learning requires a prolonged consolidation period

Precise Coulomb wave functions for a wide range of complex l, eta and z

A new algorithm to calculate Coulomb wave functions with all of its arguments complex is proposed. For that purpose, standard methods such as continued fractions and power/asymptotic series are combined with direct integrations of the Schrodinger equation in order to provide very stable calculations, even for large values of |eta| or |Im(l)|. Moreover, a simple analytic continuation for Re(z) < 0 is introduced, so that this zone of the complex z-plane does not pose any problem. This code is particularly well suited for low-energy calculations and the calculation of resonances with extremely small widths. Numerical instabilities appear, however, when both |eta| and |Im(l)| are large and |Re(l)| comparable or smaller than |Im(l)|

Geometric Shaping of 2-D Constellations in the Presence of Laser Phase Noise

In this article, we propose a geometric shaping (GS) strategy to design 8, 16, 32, and 64 -ary modulation formats for the optical fibre channel impaired by both additive white Gaussian (AWGN) and phase noise. The constellations were optimised to maximise generalised mutual information (GMI) using a mismatched channel model. The presented formats demonstrate an enhanced signal-to-noise ratio (SNR) tolerance in high phase noise regimes when compared with their quadrature amplitude modulation (QAM) or AWGN-optimised counterparts. By putting the optimisation results in the context of the 400ZR implementation agreement, we show that GS alone can either relax the laser linewidth (LW) or carrier phase estimation (CPE) requirements of 400 Gbit/s transmission links and beyond. Following the GMI validation, the performance of the presented formats was examined in terms of post forward error correction (FEC) bit-error-rate (BER) for a soft decision (SD) extended Hamming code (128, 120), implemented as per the 400ZR implementation agreement. We demonstrate gains of up to 1.2 dB when compared to the 64 -ary AWGN shaped formats

Ensino da disciplina de matemática a distância : é possível?

Orientador : Profº. Carlos RoballoMonografia (especialização) - Universidade Federal do Paraná, Setor de Educação, Curso de Especialização em Educação a DistânciaInclui referênciasResumo: A Educação Matemática vem sofrendo constantes mudanças, mesmo achando-se que a disciplina de matemática é algo imutável, a grande diferença ou talvez problema é saber reconhecer o que vem a ser a educação matemática, uma vez que tem-se falado muito nela, porém nas formas de aprendizagem e disciplina. Confunde-se também os papeis de matemático e educador matemático, existe sim, suas diferenciações. Neste trabalho de monografia foi feito um breve relato sobre a história da educação á distância e a evolução da educação matemática. E é nesse cenário de grandes controvérsias, que surge agora a Educação a distância, uma nova modalidade de ensino com suas normas, legislações, metodologias, tecnologias e desafios. Busca-se com essa pesquisa uma comparação entre as dificuldades do ensino presencial com o ensino a distância, pois se no ensino presencial da disciplina de matemática há uma dificuldade enorme na aprendizagem, imagina-se que no ensino a distância tende a ser maior pela falta de contato direto em professor e aluno.Abstract: Mathematics education has been undergoing constant changes, even though I think that the discipline of mathematics is something unchangeable, or maybe the big difference problem is knowing how to recognize what comes to mathematics education, since it has been much talk about it, but forms of learning and discipline. It also confuses the roles of mathematician and mathematics educator, is yes, their differentiation. In this thesis work was done a brief account of the history of distance education and the evolution of mathematics education. And it is in this context of great controversy, which now appears to distance education, a new type of education with its rules, laws, methodologies, technologies and challenges. Search this research with a comparison between the difficulties of classroom learning with distance learning, because if the person teaching the discipline of mathematics there is a huge difficulty in learning, it is thought that in distance education tends to be greater lack direct contact with teacher and student

A novel real-time PCR assay for specific detection and quantification of Mycobacterium avium subsp. paratuberculosis in milk with the inherent possibility of differentiation between viable and dead cells

<p>Abstract</p> <p>Background</p> <p><it>Mycobacterium avium </it>subsp. <it>paratuberculosis </it>(MAP) is the etiological agent of paratuberculosis (Johne's disease) in ruminants and is suggested to be one of the etiologic factors in Crohn's disease in humans. Contaminated milk might expose humans to that pathogen. The aim of the present study was to develop a novel real-time PCR assay providing the additional possibility to detect viable <it>Mycobacterium avium </it>subsp. <it>paratuberculosis </it>(MAP) based on the MAP-specific Mptb52.16 target. The design included an internal amplification control to identify false negative results.</p> <p>Findings</p> <p>Inclusivity and exclusivity tested on 10 MAP strains, 22 non-MAP mycobacteria, and 16 raw milk microflora strains achieved 100%. The detection limit in artificially contaminated raw milk was 2.42 × 10¹MAP cells/ml milk. In a survey of naturally contaminated samples obtained from dairy herds with a known history of paratuberculosis, 47.8% pre-milk and 51.9% main milk samples tested positive. Real-time PCR-derived MAP-specific bacterial cell equivalents (bce) ranged from 1 × 10⁰to 5.1 × 10²bce/51 ml; the majority of samples had less than one bce per ml milk. Expression of the chosen target was detected in artificially contaminated raw milk as well as inoculated Dubos broth, thus confirming the real-time PCR assay's potential to detect viable MAP cells.</p> <p>Conclusions</p> <p>Concentrating the DNA of a large sample volume in combination with the newly developed real-time PCR assay permitted quantification of low levels of MAP cells in raw milk and pasteurized milk. The selected target - Mptb52.16 - is promising with regard to the detection of viable MAP. Future studies integrating quantitative DNA- and RNA-based data might provide important information for risk assessment concerning the presence of MAP in raw milk and pasteurized milk.</p

Cannabinoid receptors expression in bone marrow trephine biopsy of chronic lymphocytic leukaemia patients treated with purine analogues

Background: Cannabinoid receptors CB1 and CB2 are part the endocannabinoid system that plays an important role in the process of proliferation and apoptosis of different neoplastic cells. B-cell chronic lymphocytic leukaemia is one of the diseases in which these processes are altered. Aim: The aim of our study was the assessment of cannabinoid receptor expression on the B-lymphocytes in bone marrow trephine biopsy from leukaemic patients at diagnosis and after purine analogue treatment. Methods: The biopsy was taken routinely and standard immunohistochemical staining procedure for paraffin embedded sections was applied. The cannabinoid receptors were detected using specific primary polyclonal antibody anti-CB1 and anti-CB2. Additionally, an existence of cannabinoid receptors was confirmed by flow cytometry. Results: The results showed that the expression of CB1 receptor on the surface of neoplastic cells was lower than that of CB2 (17.0 ± 3.1% and 92.1 ± 1.7% respectively, p < 0.001). Nine of the patients responded to applied treatment with a reduction in leukaemic infiltration (77.2 ± 6.9% to 30.2 ± 6.5%, p = 0.007) and CB1 receptor expression (24.4 ± 4.8% to 8.6 ± 2.9%, p = 0.01), but there was no change in CB2 expression (91.7 ± 2.7% vs 90.9 ± 2.8%, p = 0.69). Four patients without remission expressed even greater number of the receptors. In all of the cases both cannabinoid receptor types antibodies gave positive reaction. Furthermore, the existence of cannabinoid receptors on neoplastic lymphocytes was confirmed by flow cytometry. Conclusion: The study provides original evidence for the existence of cannabinoid receptors on B-lymphocytes in chronic lymphocytic leukaemia patients. The receptors are thought to be a new structure that can modify the course of the disease and may be considered as a new target in leukaemia treatment.Обоснование: рецепторы каннабиноидов CB1 и CB2 яв ляются частью системы эндоканнабиноидов, которая играет важную роль в процессах пролиферации и апоптоза различных неопластических клеток. Одним из заболеваний, при которых происходит нарушение этих процессов, является В-клеточный хронический лимфлейкоз. Цель: оценка экспрессии рецепторов каннабиноидов на В-лимфоцитах в трепанобиоптатах у больных лейкозом до и после проведения лечения с использованием пуриновых аналогов. Методы: биоптаты получили рутинными методами; иммуногистохимическое исследование депарафинизированных срезов проводили по стандартной процедуре. Рецепторы каннабиноидов определяли с использованием специфических моноклональных антител анти-CB1 и анти-CB2. Кроме того, наличие рецепторов подтверждено при по- мощи проточной цитофлуориметрии. Результаты: показано, что экспрессия рецептора CB1 на поверхности опухолевых клеток ниже, чем экспрессия CB2 (17,0  ± 3,1% и 92,1 1,7% твенно, p < 0,001). После проведенного лечения у 9 пациентов отмечалось уменьшение лейкозного инфильтрата (77,2 6,9% до 30,2 6,5%, p = 0,007) и снижение экспрессии рецептора CB1 (24,4 4,8% до 8,6 2,9%, p = 0,01), однако различий в экспрессии CB2 не отмечали (91,7 2,7% против 90,9 2,8%, p = 0,69). У 4 пациентов, у которых не удалось достичь ремиссии, определяли даже повышение экспрессии рецепторов. Во всех случаях маркировки антителами к обоим типам рецепторов каннабиноидов отмечали поло- жительную реакцию. Более того, присутствие рецепторов каннабиноидов на злокачественных клетках подтверждали при помощи проточной цитометрии. Выводы: в ходе исследования показано изначальное наличие рецепторов каннабиноидов на В-лимфоцитах у больных хроническим лимфолейкозом. Указанные рецепторы могут быть новой структурой, которая может быть модифицирована в течение болезни, и могут считаться новой мишенью при лечении больных лейкозом

The Partially-Coherent AWGN Channel: Transceiver Strategies for Low-Complexity Fibre Links

Carrier phase estimation (CPE) is one of the key requirements to perform intradyne coherent detection in optical communication systems. Residual errors in the phase estimation at the receiver, also known as residual phase noise (RPN), follow the so-called Tikhonov distribution. In the digital domain, a channel where the phase has already been estimated by the CPE is generally known as a partially-coherent additive white Gaussian noise (PCAWGN) channel. Herein, we present a joint strategy to modulate and demodulate a 2-dimensional (2D) signal in a PCAWGN channel. Using a low-complexity demapper, we geometrically shape (GS) 8- to 64- ary modulation formats for a PCAWGN channel. Through numerical simulations, we then assess the bit-wise achievable information rates (AIRs) and post forward error correction (FEC) bit error rates (BER) of the presented constellations with the: theoretical optimum model, Euclidean model and the low-complexity PCAWGN model. The resulting constellations are shown to be tolerant to a significant amount of RPN and are therefore applicable to coherent optical communication systems using high linewidth lasers (e.g., &gt;500 kHz) and/or lower symbol rates. Moreover, we demonstrate that shaped PCAWGN constellations combined with a low-complexity demapper can either significantly relax laser linewidth (LW) or carrier phase estimation (CPE) requirements. Assuming a rate-9/10 LDPC scheme, we demonstrate post-FEC BER shaping gains of up to 2.59 dB and 2.19 dB versus uniform 64QAM and 64-ary constellations shaped for the purely AWGN channel, respectively

O PROGRAMA DE GUARDA RESPONSÁVEL DE ANIMAIS DE CURITIBA E SUA APLICAÇÃO NO ACANTONAMENTO ECOLÓGICO

Many animals are abandoned and maltreated. In Brazil and the world there are animals of defense programs. This study aimed to examine the effectiveness of the Program of Responsible Animal Guardian of the City of Curitiba and see if after carrying out activities of marionettes and delivery of the booklet through the use of questionnaires before and after testing the children participated in the Ecological Cantonment, assimilated the importance of responsible ownership. Questionnaires were administered to 126 students. In answering the pretest questionnaire on what they understood by responsible pet ownership 59 of the 93 students analyzed at this stage (the ones with pet) responded that was quality of life of the animal. After the activities in the post-test questionnaire with the participation of 126 students, 118 responded correctly on what responsible pet ownership and animal welfare. With respect to microchip and register only 90 students understood how to do it, demonstrating that the approach to this particular topic should be reconsidered. In other aspects the approach used by the program proved to be efficient and able to sensitize students to the understanding that pets deserve respect and quality of life.Muitos animais são abandonados e sofrem maus tratos. No Brasil e no mundo existem programas de defesa de animais. Este trabalho teve como objetivo analisar a eficácia do Programa da Rede de Defesa e Proteção Animal de Curitiba e verificar se depois de realizadas as atividades de teatro de fantoches e entrega da cartilha educativa, através da aplicação de questionários pré e pós teste as crianças que participaram do Acantonamento Ecológico, assimilaram a importância da guarda responsável. Os questionários foram aplicados a 126 alunos da Rede Municipal de Ensino de Curitiba. Ao responder o questionário pré teste sobre o que entendiam por guarda responsável 59 alunos dos 93 analisados nesta etapa (os que possuem animal de estimação) responderam que era a qualidade de vida do animal. Após as atividades, no questionário pós teste com a participação dos 126 alunos, 118 responderam corretamente o que é guarda responsável e bem estar animal. Com relação à microchipagem e cadastramento apenas 90 alunos compreenderam como se faz, mostrando assim, que a abordagem para este tema específico deve ser reavaliada. Nos demais aspectos a abordagem utilizada pelo programa mostrou-se eficiente e capaz de sensibilizar os alunos para a compreensão que os animais de estimação merecem respeito e qualidade de vida.