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A novel connection-based multicasting router for programmable photonic circuits
No full textIn the rapidly evolving domain of Photonic Integrated Circuits, reconfigurability is making strides through tunable waveguide elements, facilitating ‘general-purpose’ programmable waveguide grids. Routing in modern programmable photonic networks is challenging due to the numerous possibilities that exist for assigning photonic circuits in the grid. Especially the necessary scaling to devices with many more photonic elements calls for more advanced routing heuristics. We can leverage on the existing routers for electronic reconfigurable systems (FPGAs), such as the PathFinder. However, it is crucial to connect network elements while adhering to optical signals' physical restrictions. This complexity requires careful planning for smooth, error-free connections in the network infrastructure. This paper proposes a novel algorithm addressing routing challenges in programmable photonic circuits, specifically multicasting (single-source-multiple-sink) scenarios. Efficiently conserving the overall utilized routing resources stands as a crucial objective in programmable photonics routing. Our algorithm adeptly tackles multicasting routing problems with a particular focus on shortest pathlength multicasting routing. In contrast to the PathFinder, our algorithm demonstrates notable performance in optimization speed and the utilization of routing resources.In the rapidly evolving domain of Photonic Integrated Circuits, reconfigurability is making strides through tunable waveguide elements, facilitating ‘general-purpose’ programmable waveguide grids. Routing in modern programmable photonic networks is challenging due to the numerous possibilities that exist for assigning photonic circuits in the grid. Especially the necessary scaling to devices with many more photonic elements calls for more advanced routing heuristics. We can leverage on the existing routers for electronic reconfigurable systems (FPGAs), such as the PathFinder. However, it is crucial to connect network elements while adhering to optical signals' physical restrictions. This complexity requires careful planning for smooth, error-free connections in the network infrastructure. This paper proposes a novel algorithm addressing routing challenges in programmable photonic circuits, specifically multicasting (single-source-multiple-sink) scenarios. Efficiently conserving the overall utilized routing resources stands as a crucial objective in programmable photonics routing. Our algorithm adeptly tackles multicasting routing problems with a particular focus on shortest pathlength multicasting routing. In contrast to the PathFinder, our algorithm demonstrates notable performance in optimization speed and the utilization of routing resources.A
A novel theoretical analysis on mechanical properties of bolted joints under torsional loads considering service torque
No full textBolted joint is one of the most widely used connection forms in various kinds of engineering applications. However, the presence of service torque, which is generated after tightening and easily neglected, will affect the mechanical properties of bolted joints under torsional loads. In this work, the mechanical properties of bolted joints under torsional loads, as well as the corresponding torque thresholds, are theoretically analyzed. Firstly, the torque state analysis under torsional loads about the typical form of bolted joint is carried out and followed by the bolted joint with multiple plates. Torsional loads in two opposite directions along the thread axis are considered, namely loosening torsional load and tightening torsional load. Results show that the mechanical properties of bolted joints exhibit distinct characteristics in different load directions. Loss of clamping force and structural failure may be induced by loosening torsional load under specific circumstances. In contrast, the clamping force may increase under tightening torsional load. The mechanical behavior of bolted joints is determined by the friction torque combinations of various contact surfaces and the loosening or tightening torque threshold. Therefore, the torque thresholds can be used as performance characterization and control parameters to further improve the mechanical properties.Bolted joint is one of the most widely used connection forms in various kinds of engineering applications. However, the presence of service torque, which is generated after tightening and easily neglected, will affect the mechanical properties of bolted joints under torsional loads. In this work, the mechanical properties of bolted joints under torsional loads, as well as the corresponding torque thresholds, are theoretically analyzed. Firstly, the torque state analysis under torsional loads about the typical form of bolted joint is carried out and followed by the bolted joint with multiple plates. Torsional loads in two opposite directions along the thread axis are considered, namely loosening torsional load and tightening torsional load. Results show that the mechanical properties of bolted joints exhibit distinct characteristics in different load directions. Loss of clamping force and structural failure may be induced by loosening torsional load under specific circumstances. In contrast, the clamping force may increase under tightening torsional load. The mechanical behavior of bolted joints is determined by the friction torque combinations of various contact surfaces and the loosening or tightening torque threshold. Therefore, the torque thresholds can be used as performance characterization and control parameters to further improve the mechanical properties.A
Demonstration of a photonic integrated circuit for quantitative phase imaging
No full textQuantitative phase imaging (QPI) is an optical microscopy method that has been developed over nearly a century to rapidly visualize and analyze transparent or weakly scattering objects in view of biological, medical, or material science applications. The bulky nature of the most performant QPI techniques in terms of phase noise limits their large-scale deployment. In this context, the beam shaping properties of photonic chips, combined with their intrinsic compact size and low cost, could be beneficial. Here, we demonstrate the implementation of QPI with a photonic integrated circuit (PIC) used as an add-on to a standard wide-field microscope. Combining a 50 mm x 50 mm footprint PIC as a secondary coherent illuminating light source with an imaging microscope objective of numerical aperture 0.45 and implementing a phase retrieval approach based on the Kramers-Kronig relations, we achieve a phase noise of 5.5 mrad and a diffraction limited spatial resolution of 400 nm. As a result, we retrieve quantitative phase images of Escherichia coli bacteria cells and monolayers of graphene patches from which we determine a graphene monolayer thickness of 0.45 f 0.15 nm. The current phase noise level is more than five times lower than that obtained with other state-of-the-art QPI techniques using coherent light sources and comparable to their counterparts based on incoherent light sources. The PIC-based QPI technique opens new avenues for low-phase noise, miniature, robust, and cost-effective quantitative phase microscopy. (c) 2024 Chinese Laser PressQuantitative phase imaging (QPI) is an optical microscopy method that has been developed over nearly a century to rapidly visualize and analyze transparent or weakly scattering objects in view of biological, medical, or material science applications. The bulky nature of the most performant QPI techniques in terms of phase noise limits their large-scale deployment. In this context, the beam shaping properties of photonic chips, combined with their intrinsic compact size and low cost, could be beneficial. Here, we demonstrate the implementation of QPI with a photonic integrated circuit (PIC) used as an add-on to a standard wide-field microscope. Combining a 50 mm x 50 mm footprint PIC as a secondary coherent illuminating light source with an imaging microscope objective of numerical aperture 0.45 and implementing a phase retrieval approach based on the Kramers-Kronig relations, we achieve a phase noise of 5.5 mrad and a diffraction limited spatial resolution of 400 nm. As a result, we retrieve quantitative phase images of Escherichia coli bacteria cells and monolayers of graphene patches from which we determine a graphene monolayer thickness of 0.45 f 0.15 nm. The current phase noise level is more than five times lower than that obtained with other state-of-the-art QPI techniques using coherent light sources and comparable to their counterparts based on incoherent light sources. The PIC-based QPI technique opens new avenues for low-phase noise, miniature, robust, and cost-effective quantitative phase microscopy. (c) 2024 Chinese Laser PressA
Assessment of algae growth models : a response-based analysis of climate and material parameters in China
No full textBiofouling has always been a crucial issue in the deterioration of masonry construction, which can result in an aesthetic problem, compromise the mechanical quality of historic and archaeological sites and consequently cause a significant economic loss due to the need for façade maintenance and repair. As multiple climate parameters and material properties interact in a complex way and influence algae growth independently, this research aims to have a comprehensive understanding of how both material characteristics and climate parameters influence algae growth (green algae) on brick substrate. Two prediction models were employed and assessed to determine the effect of various conditions on algae growth curve. The results indicate that generally higher wind-driven rain indicates a higher risk of algae development. However, the prevailing impact of wind-driven rain is limited beyond 200 mm annual rain load. Moreover, bricks with more than 90% large pores are the most vulnerable to algae growth, while bricks with uneven pore size distribution are the most resistant.Biofouling has always been a crucial issue in the deterioration of masonry construction, which can result in an aesthetic problem, compromise the mechanical quality of historic and archaeological sites and consequently cause a significant economic loss due to the need for façade maintenance and repair. As multiple climate parameters and material properties interact in a complex way and influence algae growth independently, this research aims to have a comprehensive understanding of how both material characteristics and climate parameters influence algae growth (green algae) on brick substrate. Two prediction models were employed and assessed to determine the effect of various conditions on algae growth curve. The results indicate that generally higher wind-driven rain indicates a higher risk of algae development. However, the prevailing impact of wind-driven rain is limited beyond 200 mm annual rain load. Moreover, bricks with more than 90% large pores are the most vulnerable to algae growth, while bricks with uneven pore size distribution are the most resistant.C
Incorporating epistemic agency in UN Peacebuilding Fund Projects: Success Stories, Silences and Contestations in Liberia
No full textThe UN Sustaining Peace agenda adopted in 2016 and its UN Peacebuilding Fund projects have sought to centre Indigenous knowledges and expertise to foster sustainable peace. Drawing on an analysis of the initial, mid-term and final reports of two UN Peacebuilding Fund projects on women’s rights implemented in Liberia, and focus groups with beneficiaries, this chapter shows how reports easily accept and adopt women’s narrative epistemic agency but are unable to capture the embodied epistemic agency of the rural women, craft a simplistic idea of community, land and property and do not consider a much larger repertoire of knowledge that is legible within customary practices, performances of motherhood and religion. Ultimately, the chapter argues that the emphasis on narrative epistemic agency is problematic because it overlooks other forms of knowing, and reproduces the very gendered hierarchies of knowledge and authority that presume that material or corporeal expressions of epistemic agency are lesser than narration. With this, the chapter contributes to the feminist and postcolonial literature that seeks to uncover the violent ways in which the international order is reproduced through the disciplining of experiences and ways of knowing.The UN Sustaining Peace agenda adopted in 2016 and its UN Peacebuilding Fund projects have sought to centre Indigenous knowledges and expertise to foster sustainable peace. Drawing on an analysis of the initial, mid-term and final reports of two UN Peacebuilding Fund projects on women’s rights implemented in Liberia, and focus groups with beneficiaries, this chapter shows how reports easily accept and adopt women’s narrative epistemic agency but are unable to capture the embodied epistemic agency of the rural women, craft a simplistic idea of community, land and property and do not consider a much larger repertoire of knowledge that is legible within customary practices, performances of motherhood and religion. Ultimately, the chapter argues that the emphasis on narrative epistemic agency is problematic because it overlooks other forms of knowing, and reproduces the very gendered hierarchies of knowledge and authority that presume that material or corporeal expressions of epistemic agency are lesser than narration. With this, the chapter contributes to the feminist and postcolonial literature that seeks to uncover the violent ways in which the international order is reproduced through the disciplining of experiences and ways of knowing.
The revolutionary road to me : identity politics and the western left /
No full text"This book examines why so much of the Western political left has foundered because of identity politics. Identity issues have deflected many good organisations from their purpose in the world and diverted their energies inwards into intractable conflicts. The Western left lost its way: it has ignored real people and their lives"--"This book examines why so much of the Western political left has foundered because of identity politics. Identity issues have deflected many good organisations from their purpose in the world and diverted their energies inwards into intractable conflicts. The Western left lost its way: it has ignored real people and their lives"-
A f entanyl hapten-displaying lipid nanoparticle vaccine that non-covalently encapsulates a TLR7/8 agonist and T-helper epitope induces protective anti-fentanyl immunity
No full textOpioid use disorder - particularly involving fentanyl - has precipitated a public health crisis characterized by a significant increase in addiction and overdose-related deaths. Fentanyl-specific immunotherapy, which aims at inducing fentanyl-specific antibodies capable of binding fentanyl molecules in the bloodstream, preventing their entry in the central nervous system, is therefore gaining momentum. Conventional opioid designs rely on the covalent conjugation of fentanyl analogues to immunogenic carrier proteins that hold the inherent capacity of mounting immunodominant responses. Here, we present an alternative fentanyl vaccine design that utilizes a non-covalent assembly of lipid nanoparticles (LNPs) to deliver fentanyl haptens in conjunction with a CD4+ T-helper peptide epitope and an imidazoquinoline TLR7/8 agonist. Our results demonstrate that a single intramuscular administration of the LNP-based nanovaccine elicits fentanyl-specific antibodies, significantly mitigating the effects of opioid overdose in preclinical mouse models. Furthermore, we analyzed the immunobiological behavior of the vaccine in vivo in mouse models, providing evidence that covalent attachment of a fentanyl hapten to a carrier proteins or peptide epitope is not necessary for inducing an effective immune response. However, co-delivery - specifically, the physical assembly of all immune cues into an LNP - remains essential for inducing hapten-specific immunity.Opioid use disorder - particularly involving fentanyl - has precipitated a public health crisis characterized by a significant increase in addiction and overdose-related deaths. Fentanyl-specific immunotherapy, which aims at inducing fentanyl-specific antibodies capable of binding fentanyl molecules in the bloodstream, preventing their entry in the central nervous system, is therefore gaining momentum. Conventional opioid designs rely on the covalent conjugation of fentanyl analogues to immunogenic carrier proteins that hold the inherent capacity of mounting immunodominant responses. Here, we present an alternative fentanyl vaccine design that utilizes a non-covalent assembly of lipid nanoparticles (LNPs) to deliver fentanyl haptens in conjunction with a CD4+ T-helper peptide epitope and an imidazoquinoline TLR7/8 agonist. Our results demonstrate that a single intramuscular administration of the LNP-based nanovaccine elicits fentanyl-specific antibodies, significantly mitigating the effects of opioid overdose in preclinical mouse models. Furthermore, we analyzed the immunobiological behavior of the vaccine in vivo in mouse models, providing evidence that covalent attachment of a fentanyl hapten to a carrier proteins or peptide epitope is not necessary for inducing an effective immune response. However, co-delivery - specifically, the physical assembly of all immune cues into an LNP - remains essential for inducing hapten-specific immunity.A
Molecular fingerprints of cell size sensing and mating type differentiation in pennate diatoms
No full textA unique cell size-sensing mechanism is at the heart of the life cycle of diatoms. During population growth, cell size decreases until a sexual size threshold (SST) is reached, below which cells become sexually competent. In most pennate diatoms, the two mating types undergo biochemical and behavioral differentiation below the SST, although the molecular pathways underlying their size-dependent maturation remain unknown. Here, we developed a method to shorten the generation time of Cylindrotheca closterium through single-cell microsurgery, enabling the transcriptomic comparison of genetically identical large and undifferentiated cells with small, sexually competent cells for six different genotypes. We identified 21 genes upregulated in small cells regardless of their mating type, revealing how cells undergo specific transcriptional reprogramming when passing the SST. Furthermore, we revealed a size-regulated gene cluster with three mating type-specific genes susceptible to sex-inducing pheromones. In addition, comparative transcriptomics confirmed the shared mating type specificity of Mating-type Related Minus 2 homologs in three pennate diatoms, suggesting them to be part of a conserved partner recognition mechanism. This study sheds light on how diatoms acquire sexual competence in a strictly size-dependent manner, revealing a complex machinery underlying size-dependent maturation, mating behavior, and heterothally in pennate diatoms.A unique cell size-sensing mechanism is at the heart of the life cycle of diatoms. During population growth, cell size decreases until a sexual size threshold (SST) is reached, below which cells become sexually competent. In most pennate diatoms, the two mating types undergo biochemical and behavioral differentiation below the SST, although the molecular pathways underlying their size-dependent maturation remain unknown. Here, we developed a method to shorten the generation time of Cylindrotheca closterium through single-cell microsurgery, enabling the transcriptomic comparison of genetically identical large and undifferentiated cells with small, sexually competent cells for six different genotypes. We identified 21 genes upregulated in small cells regardless of their mating type, revealing how cells undergo specific transcriptional reprogramming when passing the SST. Furthermore, we revealed a size-regulated gene cluster with three mating type-specific genes susceptible to sex-inducing pheromones. In addition, comparative transcriptomics confirmed the shared mating type specificity of Mating-type Related Minus 2 homologs in three pennate diatoms, suggesting them to be part of a conserved partner recognition mechanism. This study sheds light on how diatoms acquire sexual competence in a strictly size-dependent manner, revealing a complex machinery underlying size-dependent maturation, mating behavior, and heterothally in pennate diatoms.A
Animals and Greek cinema : an inquiry into the nonhuman
No full textThis book offers a non-anthropocentric account of a national cinema. Drawing on cutting-edge developments in Animal (film) studies, the book gathers a wide range of species and genres to discuss the Greek cinematic animal. This en-tails recalibrating the readers’/viewers’ gazes to include particular nonhumans, often displaced in the frame’s margins. While acknowledging the cost paid in animal suffering for Greek cinema to rise, the book features instances of animal-human bonding. Combining close readings with interviews with directors, human actors, screenwriters, cinematographers, producers, special effects artists, and animal wranglers, this book proposes a paradigm of human-animal praxis, arguing that revisiting nonhuman images can lead to renewed ethical relations, and to less speciesist cinemas, film industries, and societies.This book offers a non-anthropocentric account of a national cinema. Drawing on cutting-edge developments in Animal (film) studies, the book gathers a wide range of species and genres to discuss the Greek cinematic animal. This en-tails recalibrating the readers’/viewers’ gazes to include particular nonhumans, often displaced in the frame’s margins. While acknowledging the cost paid in animal suffering for Greek cinema to rise, the book features instances of animal-human bonding. Combining close readings with interviews with directors, human actors, screenwriters, cinematographers, producers, special effects artists, and animal wranglers, this book proposes a paradigm of human-animal praxis, arguing that revisiting nonhuman images can lead to renewed ethical relations, and to less speciesist cinemas, film industries, and societies.B