Photonic integration enabling new multiplexing concepts in optical board-to-board and rack-to-rack interconnects

New broadband applications are causing the datacenters to proliferate, raising the bar for higher interconnection speeds. So far, optical board-to-board and rack-to-rack interconnects relied primarily on low-cost commodity optical components assembled in a single package. Although this concept proved successful in the first generations of optical-interconnect modules, scalability is a daunting issue as signaling rates extend beyond 25 Gb/s. In this paper we present our work towards the development of two technology platforms for migration beyond Infiniband enhanced data rate (EDR), introducing new concepts in board-to-board and rack-to-rack interconnects. The first platform is developed in the framework of MIRAGE European project and relies on proven VCSEL technology, exploiting the inherent cost, yield, reliability and power consumption advantages of VCSELs. Wavelength multiplexing, PAM-4 modulation and multi-core fiber (MCF) multiplexing are introduced by combining VCSELs with integrated Si and glass photonics as well as BiCMOS electronics. An in-plane MCF-to-SOI interface is demonstrated, allowing coupling from the MCF cores to 340x400 nm Si waveguides. Development of a low-power VCSEL driver with integrated feed-forward equalizer is reported, allowing PAM-4 modulation of a bandwidth-limited VCSEL beyond 25 Gbaud. The second platform, developed within the frames of the European project PHOXTROT, considers the use of modulation formats of increased complexity in the context of optical interconnects. Powered by the evolution of DSP technology and towards an integration path between inter and intra datacenter traffic, this platform investigates optical interconnection system concepts capable to support 16QAM 40GBd data traffic, exploiting the advancements of silicon and polymer technologies

Stability at the half pin-frame interface on external fixation constructs

Abstract A mechanical study investigating the use of two different methods (grub and bolt screws) to secure external fixation half pins to circular frames. A four part experiment: (1) Grub and bolt screws were used to secure half pins in Taylor Spatial frames. Loosening torques were measured using a calibrated torque wrench. (2) Using universal testing machine (UTM), axial loading was applied to establish thresholds for loosening in grub and bolt screw constructs. (3) We established the application torque to produce failure at the head–driver interface using these two methods. (4) Grub and bolt screw constructs were created controlling torque. Using UTM, axial loading was applied to establish thresholds for loosening. Statistical analysis was conducted using SPSS v20.0.0. (1) Higher torque is employed when bolt rather than grub screws is used to secure half pins on Rancho cubes (p < 0.05). (2) Loading threshold for loosening is higher in bolt screw constructs when the torque applied to secure the constructs is not controlled (p < 0.05). (3) Torque required for failure at the head–driver interface was 5.3 Nm for grub screws and 9.9 Nm for bolts. (4) Loading threshold for loosening is higher in grub screw constructs when the same torque was applied to secure them (p < 0.05). Bolt screws can be employed to secure the half pin–frame interface. They offer good stability and reduce failure at the head–driver interface. Further research is needed to determine the mechanical properties of such constructs in vivo

Optimizing Druggability through Liposomal Formulations: New Approaches to an Old Concept

Developing innovative delivery strategies remains an ongoing task to improve both efficacy and safety of drug-based therapy. Nanomedicine is now a promising field of investigation, rising high expectancies for treating various diseases such as malignancies. Putting drugs into liposome is an old story that started in the late 1960s. Because of the near-total biocompatibility of their lipidic bilayer, liposomes are less concerned with the safety issue related to the possible long-term accumulation in the body of most nanoobjects currently developed in nanomedicine. Additionally, novel techniques and recent efforts to achieve better stability (e.g., through sheddable coating), combined with a higher selectivity towards target cells (e.g., by anchoring monoclonal antibodies or incorporating phage fusion protein), make new liposomal drugs an attractive and challenging opportunity to improve clinical outcome in a variety of disease. This review covers the physicochemistry of liposomes and the recent technical improvements in the preparation of liposome-encapsulated drugs in regard to the scientific and medical stakes

Hyperparameter optimization in deep multi-target prediction

As a result of the ever increasing complexity of configuring and fine-tuning machine learning models, the field of automated machine learning (AutoML) has emerged over the past decade. However, software implementations like Auto-WEKA and Auto-sklearn typically focus on classical machine learning (ML) tasks such as classification and regression. Our work can be seen as the first attempt at offering a single AutoML framework for most problem settings that fall under the umbrella of multi-target prediction, which includes popular ML settings such as multi-label classification, multivariate regression, multi-task learning, dyadic prediction, matrix completion, and zero-shot learning. Automated problem selection and model configuration are achieved by extending DeepMTP, a general deep learning framework for MTP problem settings, with popular hyperparameter optimization (HPO) methods. Our extensive benchmarking across different datasets and MTP problem settings identifies cases where specific HPO methods outperform others.Comment: 17 pages, 4 figures, 1 tabl

Ο αυτοαναφορικός Γιάννης Ρίτσος

Στόχος της διπλωματικής εργασίας είναι η ιστορικο-φιλολογική προσέγγιση κειμένων του Γιάννη Ρίτσου, στα οποία εντοπίζεται η μεγάλη λειτουργική σημασία της αυτοαναφορικότητας για τον σχηματισμό της ποιητικής του ιδεολογίας. Θα εξεταστούν δύο κατηγορίες κειμένων: πεζά/δοκιμιακά και ποιητικά. Η εμπλοκή του Ρίτσου εντός ενός πλαισίου μαχητικής ιδεολογικής πάλης, από την αφετηρία ακόμη της καλλιτεχνικής του πορείας, τον οδηγεί στην κατάθεση πολλών αυτοαναφορικών κειμένων, που υπερασπίζονται τόσο συγκεκριμένες αισθητικές επιλογές, όσο και την ίδια του την πολιτική στράτευση ως καλλιτέχνη. Επιπλέον, επεξεργάζεται ένα πλήθος ποιημάτων ποιητικής που αναφέρονται στη διαδικασία και τους αναβαθμούς της ποιητικής γραφής, την περιγραφή του ποιητικού εργαστηρίου, αλλά και τα εγγενή χαρακτηριστικά του ποιητικού γλωσσικού κώδικα. Στο πρώτο μέρος της διατριβής θα επιχειρηθεί μια συστηματική θεωρητική προσέγγιση της έννοιας της αυτοαναφορικότητας αλλά και της στράτευσης, και θα αναλυθεί η ιδιαίτερη αποτύπωσή τους σε δοκιμιακά αλλά και ποιητικά κείμενα του συγγραφέα. Το δεύτερο μέρος θα αφιερωθεί στη μελέτη της ιδιότυπης αντίληψης που οικοδομεί ο Ρίτσος γύρω από τη στράτευση, προσεγγίζοντάς την αιρετικά μέσα από το πρίσμα μιας ιδιότυπης προσωπικής μορφής Αισθητισμού, η οποία και αποτελεί ένα από τα σημαντικότερα σημεία για την κατανόηση της ποιητικής του ιδεολογίας σε όλες της τις εκφάνσεις. Σε μεθοδολογικό επίπεδο, εκτός της κειμενοκεντρικής προσέγγισης, η διατριβή θα εγκολπώσει και την αρχειακή έρευνα αξιοποιώντας πρωτότυπο υλικό που έχει εντοπιστεί σε οργανωμένες δομές και στην κατοχή ιδιωτών, και το οποίο θα παρουσιαστεί διεξοδικά. Η έκταση, η θεματική και η μορφολογία της ποιητικής παραγωγής του Ρίτσου είναι τέτοιες που εμποδίζουν οποιαδήποτε αίσθηση συνοχής ή ποιητικού κέντρου. Εντούτοις, μέσω της αναλυτικής αξιοποίησης της έννοιας της αυτοαναφορικότητας είναι δυνατόν να εντοπιστεί η ύπαρξη μιας αφανούς ποιητικής θεωρίας οι μαρτυρίες της οποίας διατρέχουν το έργο του σε όλη του την έκταση.This dissertation aims at analyzing the functionality of the textual and rhetorical status of self-referentiality in the critical and poetic texts of Yannis Ritsos and the ways through which the construction of his poetic ideology takes place. We will read the texts through an historical and philological approach. From the beginning of his artistic trajectory, Ritsos engaged in the ideological and political battle and was characterized as a politically committed poet. He thus wrote many critical self-referential texts that sought to defend certain aesthetic choices, and also his political engagement within his poetic work. He also produced many “poems of poetics”, which refer directly to the thematics of poetic discourse and the peculiar characteristics of the poetic language code. The first part of the dissertation will undertake a systematic theoretical analysis of the concepts of self-referentiality and intellectual commitment. Furthermore, we will try to explore the ways in which these two key-concepts are depicted in the poetic and critical texts of the greek poet. The second part will include the study of the poet’s conscious awareness of political commitment through poetic practice, and his perception of it as part of a distinctive personal Aestheticism –a perception that is vital for the overall interpretation of his poetic ideology. Methodologically, except from the close textual analysis, the dissertation will engage with archival research, making use of master documents from the poet’s literary archive that have been detected in public and private collections. The tremendous range of thematics and forms of Ritsos’ poetry usually obscures the possibility of locating a certain “poetic centre” in his production. Nonetheless, through the analytical deployment of the concept of self-referentiality, it is possible to identify the presence of an inconspicuous poetic theory within his work, which characterizes his production as a whole