bluuebunny/crossref_metadata_2025 huggingface dataset:
The Conception of Morality in Moral Realism
Authors: Zhang Feng
Published: January 2024

Moral realism is one of the most distinctive and influential Chinese theories of international relations (IR) to have emerged in recent years. This chapter explores the conception of morality in moral realism by situating it within broad intellectual approaches to morality. It offers a critique by pointing out its narrowness and instrumentality. The conception is explicitly instrumental in accordance with realist commitments. It is narrow in that it is restricted to governmental morality judged by the extent to which policies serve national interests and capabilities. Subjects of genuine moral significance, such as justice and care, are left out of the picture. The chapter suggests the value of a broader conception of morality and pinpoints avenues for the further development of the theory.
Moral Realism and Hegemonic Transition
Authors: Platias Athanasios , Trigkas Vasilis
Published: January 2024

Yan Xuetong’s agent-centric theory of hegemonic transition has brought leadership back into the strategic equation. In this chapter we first utilize Yan’s theory to evaluate perspectives about hegemonic transition between China and the US. Second, we further elaborate on how a theory of hegemonic transition built on political leadership could be possibly refined within a neoclassical realist framework where the system conditions and delimits strategic action. Third, we approach Yan’s theory from a classical realist perspective: we draw from the Hellenic classical tradition to highlight parallel concepts to Yan’s core ideas on strategic credibility and moral realism that can help us sketch teachable character traits in support of reformist political leadership. Developed independently into two heterogenous interstate systems (the Sinic and the Hellenic), these leadership personality attributes have an air of universality capable of both educating and inspiring strategic elites in pursuit of political reform. We conclude by extrapolating the theory of moral realism on the future of Sino–US strategic competition and China’s potential to lead globally.
Neoliberalism, Creativity and Cities
Authors: Hollands Robert G.
Published: January 2024

This opening chapter begins with some illustrative examples of cities around the world attempting to brand themselves as creative through reference to various aspects of their cultural economy. It then introduces the concept of neoliberalism and shows how it is closely related to the debate about creativity and urban cultural regeneration. This is followed by a short discussion of the limits of the neoliberal city generally before introducing the book’s main themes and chapter contents. It concludes by arguing that there is a case for moving beyond the existing neoliberal creative city and considering the possibility of an alternative urban future.
Association
Authors: Kaufmann Mareile
Published: January 2024

Association has become a central aspect of surveillance and a key practice of making information matter. It is critical to any kind of profiling that we experience on an everyday basis. To associate is to join, to make a connection ‘in an interest, object, employment or purpose’ (Harper, nd). One of the most widespread ways of analysing information is indeed to make a connection between different datasets. In her work on data derivatives Louise Amoore speaks of an ‘ontology of association’ (2011: 27). This means that associating data is not just a knowledge practice, but it describes a specific way in which data materialize and come to exist together. The most common approach of associating different datasets with each other follow a Boolean logic (Kitchin, 2016), named after the mathematician George Boole. We know them as if-then rules, that is: when if is true, then is executed. By means of if-then instructions disaggregated data are associated ‘to derive a lively and alert new form of data derivative – a flag, map or score that will go on to live and act in the world’ (Amoore, 2011: 27). The aim of associative practices is to connect different sets of information and to derive patterns from them (Kaufmann, Egbert, and Leese, 2019). What is more, such patterns, again, are likely to be associated with actions that matter to society. Whether a pattern is considered meaningful and actionable depends on many aspects, not least those involved in associating. Association is a classic analytic practice, which is also used to process analogue information. With the rise of digital information, however, association has shifted in terms of reach and quality.
Secrecy
Authors: Kaufmann Mareile
Published: January 2024

Information is not always out there, waiting to be accessed, collected, processed, and revealed. We may be under the impression that information matters because it is made seen, associated and known. After all, the word information describes an act of informing, communicating, and instructing. On closer inspection one may find that most practices of making information matter, however, are exercised and known by few, even if the actual practice may affect many. Thus, information matters not only when it is accessed and explored for patterns, or when it is converted in order to question association. Information matters, too, when it resists being known, when it is shared among few or when it remains inaccessible. One engagement with information is to actively keep it from being out in the open, to make it known to select people only. Secrecy is a practice of making information matter. However, secrecy is not the opposite of making information seen or known. The relationship between secrecy and seeing, knowing or watching is not a dialectical one. Secrecy is more about how information is seen, known, accessed, and watched, by whom, and how that matters. Georg Simmel argued that the interplay of knowing and not knowing matters as it shapes social relations. Not only ‘knowledge of each other’ (1906: 444) is a socializing force, but secrecy and concealment disrupt and vitalize socializing forces (Simmel, 1906: 448). Or as Susanne Krasmann puts it: ‘In an imagined world without secrets, there would be no curiosity or confidentiality, no sincerity or trust, and no political possibility of thinking otherwise’ (2019: 690).
Speculation
Authors: Kaufmann Mareile
Published: January 2024

What will happen to the Internet in the future? ‘I will answer very simply that the Internet will disappear’, is what then-Google Chairman Eric Schmidt famously answered at the World Economic Forum 2015 (Schmidt in Szalai, 2015: online). Two years earlier, filmmaker, artist, and writer Hito Steyerl asked ‘Is the internet dead?’ (2013: online). Eric Schmidt and Hito Steyerl could not be more different in the ways in which they engage with questions concerning the presence of the Internet. While Schmidt envisions a seamless transition to a trans-societist condition via ‘devices, sensors, things that you are wearing, things that you are interacting with that you won’t even sense’ (Schmidt in Szalai, 2015: online), Steyerl asks whether that kind of Internet actually ‘stopped being a possibility’ (2013: online), because it is left to those who commercialize and racialize instead of forming potentials. While the Internet and more general processes of digitization should not be confused, these discourses about the future of the Internet also illustrate how digital information matters and may come to matter. Hito Steyerl is one of many artists who calls attention to the ethics and politics of the Internet. Since the early 2000s many post-Internet art projects emerged, but only some of them take a stance on what it means to make online or digital information matter through art. Furthermore, not all who create artistic content through, with or in relation to the Internet consider themselves part of the post-Internet art community.
Tales of Machismo and Motherhood: Gendered Changes across War and Peace
Authors: Weber Sanne
Published: January 2024

This chapter describes gender roles of survivors and ex-combatants before, during and after Colombia’s conflict. Rather than understanding ‘gender’ solely through the lens of sexual violence, it instead focuses on the everyday experiences of conflict and post-conflict lives, and how these are defined by structures of gender inequality. The chapter describes how conflict disrupted traditional gender relations, producing emancipatory experiences for women in both groups, as well as changes in models of masculinities. Such changes could be building blocks for post-conflict gender equality. Unfortunately, the chapter also identifies the continuities of structural gendered inequalities and traditional female roles in the post-agreement situation. It specifically zooms in on women’s participation in community structures during and after conflict, as well as their own organizational spaces. Such organizational processes could provide building blocks for active citizenship.
‘#RoeVsWadeOverturned: Any Idea How Fast Your #PeriodtrackingApp Can Lead To Jail?’: Digital Disengagement and the Repeal of Roe vs Wade
Authors: Martin Sam
Published: January 2024

This chapter frames the situation regarding menstrual and fertility apps in the context of post-pandemic health app-ization and datafication, which lead to increased digital surveillance and digital authoritarianism. This chapter shows how acutely aware women are becoming of how vulnerable apps and the personal data contained therein are making them in relation to state surveillance capitalism. Social media discourse and sentiment analysis are used to understand how, in the immediate aftermath of the overturning of Roe vs Wade in the US, women and their allies strove to effectively delete data, digitally disengage, algorithmically disrupt data or opt-out of sharing their data via period-tracking apps. Tracking practices of deletion, disruption and opt-out, this chapter theorizes digital disengagement as a form of resistance, addressing the ongoing tensions that can arise between a more technologically informed public and the authorities in terms of the need to protect rights to self-track health without criminalization.
Data Minimalism and Digital Disengagement in COVID-19 Hacktivism
Authors: Richterich Annika
Published: January 2024

This chapter discusses data minimalism as means of digital disengagement. It focuses on the case of the Chaos Computer Club (CCC), a German hacker association that is known for high levels of digital skills and tech-political expertise. Specifically, it examines members’ ‘hacktivism’ during the first two years of the COVID-19 pandemic. Responding to COVID-related technology such as contact-tracing apps, the CCC presented recommendations and strategies for digital disengagement through data minimalism and technological downgrading. Advocating for partial or more substantial digital disengagement, the hacker association stressed that digital approaches are not preferable per se: instead, their adequacy should be assessed in relation to the specific problem, while also considering the advantages of low(er)-tech options. In this way, the hacker association confronted data expansionism and tech solutionism, which were flourishing under the pretext of epidemiological urgency. In exploring the CCC’s hacktivism, this chapter elaborates on digital disengagement as an informed choice and a matter of agency rather than an involuntary ‘anomaly’.
Digital Solutionism Meets Pandemic Imaginaries
Authors: Kuntsman Adi
Published: January 2024

This chapter discusses environmental impacts of the COVID-19 pandemic, and, more specifically, the impact of the overall shift towards digital technologies during the pandemic and in post-pandemic times. Drawing on small-scale observations of UK media coverage and a pilot systematic review of academic publications, the chapter focuses on the striking absence of intersections between discussions around pandemic digitization and questions of climate change and environmental degradation. The chapter considers two key elements of the digital disengagement paradigm: denaturalizing the digital, and using digital reduction and refusal as a starting point, rather than as an afterthought. In doing so, the chapter foregrounds digital reduction, refusal and opt-out, seeking new visions that promote climate-driven digital disengagement, instead of merely documenting digital harms or ways in which they are ignored.
State Violence, Digital Harms and the COVID-19 Pandemic: Imagining Refusal, Resistance and Community Self-Defence
Authors: Gangadharan Seeta Peña , Williams Patrick , Kuntsman Adi , Martin Sam , Miyake Esperanza
Published: January 2024

In exploring the relationships between the COVID-19 pandemic, digital technologies and social injustices, this book strives to go beyond individual acts and practices of refusal and opt-out, and address these in broader socio-political contexts. As editors, we were privileged to learn of, and be inspired by, the work of Seeta Peña Gangadharan and Patrick Williams. In true pandemic fashion, we met over a Zoom call to ask them about their work and their thoughts on the rise of digitization during the pandemic years, and the shrinking of possibilities to escape or refuse the prescribed use of technology. Transcribed and lightly edited, the conversation is presented in the chapter.
Real-time phase retrieval in division of aperture microscopy with the transport of intensity equation
Authors: Fernández Ariel , Llaguno Juan M. , Silva Alejandro , Alonso Julia R.
Published: January 2024

The transport of intensity equation (TIE) allows to recover the phase of a microscopy sample from differently focused intensity measures along the axial direction of its optical field. In the present work, we propose a cost-effective technique for snapshot phase retrieval with TIE. The optics of a commercially available camera is replaced with a doublet system consisting of a microscope objective and a lenslet array with an extra lens mask attached to it. The system allows to obtain, in real-time and with no mechanical shift of either the sample or the sensor, the in-focus as well as a defocused image of the sample. From these two sub-aperture images, the intensity derivative term in TIE can then be approximated after image rectification. Phase is then retrieved for static as well as dynamic samples over the common view area. Validation experiments are presented.
Improving energy efficiency: a highly efficient coaxial design for a laser ranging system with a splicing lens
Authors: Pan Shuixin , Cui Jinlin , Zhang Yueqiang , Hu Biao , Liu Xiaolin , Yu Qifeng
Published: January 2024

Light detection and ranging (LiDAR) systems have made significant contributions in different applications. The laser ranging (LR) system is one of the core components of LiDARs. However, existing coaxial LR systems suffer from low energy efficiency due to obstruction of the reflection mirror. In this study, we carefully design a laser transmitter and receiver subsystem and consequently propose a highly energy-efficient coaxial design for a time of light-based LR system, where a perforated mirror and splicing lens account for the promotion of energy efficiency. The small hole in the perforated mirror is located on the object focus of the focusing lens to ensure the laser beam will pass through the perforated mirror without obstructions. The ring-shape splicing lens, consisting of two parts, is used for laser collimation and laser reception simultaneously. Laboratory experiments proved that the proposed design eliminates the complex calibration process for noncoaxial LR systems while reaching a comparable energy efficiency, which is higher than 98%. We believe it is an economical yet efficient way to promote the energy efficiency of coaxial LR systems.
Prediction of metallo-dielectric transmission filter performance based on underlying dispersion relations
Authors: Banerjee Partha P. , Al-Ghezi Hammid , Chen Guo , Slagle Jonathan , Rumi Mariacristina , Gnawali Rudra , Evans Dean R.
Published: January 2024

The dispersion relation for electromagnetic/optical wave propagation based on the
Helmholtz equation for an infinite one-dimensional metallo-dielectric
structure is derived using the Bloch theorem and heuristically
modified to include material dispersion. We investigate the connection
between the dispersion relation of an infinite metallo-dielectric
structure with the transmittance characteristics of finite
metallo-dielectric structures. The dispersion relation is used to
determine the center wavelength and bandwidth as a function of the
material properties and the thicknesses of the metal and dielectric
layers. These estimates are found to be in excellent agreement with
the values obtained from numerically calculated transmittance spectra
using the transfer matrix method for finite metallo-dielectric
structures with the same building units. The dispersion relation
calculations and simulations for the transmittance are done for an
ideal case where the real part for the
refractive index of the metal and imaginary part for the refractive
index of the dielectric are zero, and also with actual values of the real and imaginary parts of the
refractive index for the metal and dielectric obtained from
literature, instead of using the canonical Drude model for the metal.
It is shown that the real part of the dispersion relation for the
actual case is almost identical to the
ideal case in the visible and NIR range,
implying that essential information on the center wavelength and
bandwidth can be obtained from the ideal
dispersion relation. It is also found that an ideal metal and
dielectric give near-unity transmittance in the passband. It is
predominantly the presence of a finite real part of the refractive
index of the metal that introduces attenuation. The effective
refractive index of the structure can also be determined. Oscillations
present in the transmittance spectrum can be explained as a
Fabry–Perot effect. Approximate simple estimates of the center
wavelength and bandwidth can be useful in initiating intelligent
designs of finite metallo-dielectric filter structures for fabrication
and characterization.
Adaptive phase-shifting interferometry based on a phase-shifting digital holography algorithm
Authors: Han Xianxin , Wang Yuheng , Bu Zhengyang , Bu Xiaoya , Li Hongyun , Liu Shengde , Zhong Liyun , Lu Xiaoxu
Published: January 2024

Phase-shifting interferometry (PSI) requires accurate phase shifts between interferograms for realizing high-accuracy phase retrieval. This paper presents an adaptive PSI through synchronously capturing phase shifts measurement interferograms and phase measurement interferograms, in which the former is a series of spatial carrier frequency phase-shifting interferograms generated by an additional assembly and the phase shifts are calculated with the single-spectrum phase shifts measurement algorithm (SS-PSMA), the latter is employed for phase retrieval with an adaptive phase-shifting digital holography algorithm (PSDHA) based on complex amplitude recovery. In addition to exhibiting excellent reliability, high-accuracy phase retrieval (0.02 rad), and short calculation time (<25 ms), the proposed adaptive PSDHA is suitable for various interferograms with different fringe shapes and numbers. Importantly, both simulation analysis and experimental result demonstrate that this adaptive PSI based on PSDHA can effectively eliminate phase-shifting errors caused by phase shifter and external disturbance, ensuring high-accuracy phase shifts measurement and phase retrieval, meanwhile significantly reducing phase-shifting interferograms acquisition time and phase retrieval calculation time.
Laser frequency stabilization by modulation transfer spectroscopy and balanced detection of molecular iodine for laser cooling of 174Yb
Authors: de Melo Álvaro M. G. , Letellier Hector , Apoorva Apoorva , Glicenstein Antoine , Kaiser Robin
Published: January 2024

We report laser frequency stabilization by the combination of modulation transfer spectroscopy and balanced detection of a relatively weak hyperfine transition of the R(158)25-0 line of molecular iodine (127I2), which is used as a new frequency reference for laser trapping and cooling of 174Yb on the 1S0 − 3P1 transition. The atomic cloud is characterized by time-of-flight measurements, and an on-resonance optical depth of up to 47 is obtained. We show laser noise reduction and characterize the short-term laser frequency instability by the Allan deviation of the laser fractional frequency. The minimum measured value is 3.9 ×10−13 at 0.17 s of averaging time.
General framework for ultrafast nonlinear photonics: unifying single and multi-envelope treatments [Invited]
Authors: Phillips C. R. , Jankowski M. , Flemens N. , Fejer M. M.
Published: January 2024

Numerical modeling of ultrashort pulse propagation is important for designing and understanding the underlying dynamical processes in devices that take advantage of highly nonlinear interactions in dispersion-engineered optical waveguides. Once the spectral bandwidth reaches an octave or more, multiple types of nonlinear polarization terms can drive individual optical frequencies. This issue is particularly prominent in χ(2) devices where all harmonics of the input pulse are generated and there can be extensive spectral overlap between them. Single-envelope approaches to pulse propagation have been developed to address these complexities; this has led to a significant mismatch between the strategies used to analyze moderate-bandwidth devices (usually involving multi-envelope models) and those used to analyze octave-spanning devices (usually involving models with one envelope per waveguide mode). Here we unify the different strategies by developing a common framework, applicable to any optical bandwidth, that allows for a side-by-side comparison between single- and multi-envelope models. We include both χ(2) and χ(3) interactions in these models, with emphasis on χ(2) interactions. We show a detailed example based on recent supercontinuum generation experiments in a thin-film LiNbO3 on sapphire quasi-phase-matching waveguide. Our simulations of this device show good agreement between single- and multi-envelope models in terms of the frequency comb properties of the electric field, even for multi-octave-spanning spectra. Building on this finding, we explore how the multi-envelope approach can be used to develop reduced models that help build physical insights about new ultrafast photonics devices enabled by modern dispersion-engineered waveguides, and discuss practical considerations for the choice of such models. More broadly, we give guidelines on the pros and cons of the different modeling strategies in the context of device design, numerical efficiency, and accuracy of the simulations.
Simultaneous generation and manipulation of terahertz waves based on nonlinear leaky-waveguide antennas with integrated bianisotropic metasurfaces
Authors: Upcraft Daniel , Oh Sang-Hyun , Kim Minseok
Published: January 2024

We hereby propose and theoretically investigate a new scheme for simultaneous generation and manipulation of terahertz (THz) waves through difference frequency generation facilitated by a metasurface-assisted nonlinear leaky waveguide antenna. The proposed structure integrates a nonlinear optical waveguide, composed of multiple Al
x
Ga1−xAs layers, with a THz leaky waveguide, wherein a bianisotropic metasurface realizes the radiating aperture. By explicitly utilizing the electric, magnetic, and magnetoelectric coupling responses of the metasurface, we demonstrate that the generated THz wave can be induced as a tightly confined, phase-matched guided mode for efficient generation of the THz wave. Additionally, this approach allows the THz wave to be transformed into a directive beam, radiating at a user-defined leakage rate and direction. Our numerical analyses suggest that THz beams ranging from 2.85 THz to 3.05 THz can be steered from 4∘ to 40∘, utilizing the inherent beam-steering capabilities of the leaky-waveguide antenna. Within this THz frequency spectrum, the phase matching condition is achieved by adjusting the optical wavelengths between 1.6μm and 1.52μm. In particular, the nonlinear conversion efficiency is 2.9 × 10−5 [1/W] at 3 THz.
Pulse buildup dynamics in a self-starting Mamyshev oscillator
Authors: Liu Jingxue , Wang Chaoran , Li Xingliang , Han Mengmeng , Zhang Shumin
Published: January 2024

The Mamyshev oscillator (MO) can generate high-performance pulses. However, due to their non-resonant cavities, they usually are not self-starting, and there is almost no effort to reveal the pulse buildup dynamics of the MO. This paper investigates the dynamic of single pulse (SP) and multi-pulse formation in a self-starting MO. It indicated that both SP self-starting and multi-pulse self-starting can be obtained by adjusting the oscillator parameters. More importantly, increasing pump power could only result in bound state pulses (BSPs) if SP self-starting was formed. With the increase of the pump power, the pulse number in BSPs would increase. However, multiple pulses could not be formed only by increasing the pump power, and the BSPs obtained here underwent SP generated from noise, amplified, and then bounded, which is different from conventional passive mode-locked fiber lasers (CPMLFLs). On the other hand, if multiple pulses were self-initiated, BSPs, pulse bunch, and harmonic mode-locked pulses (HMLPs) could be obtained by adjusting the polarization state and pump power in the cavity. Furthermore, once any of the above states are formed, if the oscillator polarization state and filter interval are unchanged, only increasing the pump power from zero, the original state can still be obtained, which is consistent with the characteristics of the CPMLFLs. These findings will provide new insights into the pulse dynamics of self-starting MO, which will be significant for studying ultrafast laser technology and nonlinear optics.
Operation-robust SiO2-based memristive application in air
Authors: Su Linlin , Li Xinwei , Yang Chengdong , Liu Yilong , Xu Lihua
Published: January 2024

In recent years, neuromorphic computing is recognized as a promising path to further improve the efficiency of integrated computing system in the post-Moore era, relying on its high parallelism. As a key fundamental element in hardware-implementing neuromorphic system, the synaptic device has made substantial research progress. Among these, SiO2 trapping-based memristive devices generally have systematically integrated merits, such as ease of fabrication and high CMOS process compatibility, but electrochemical activity to oxygen makes them unreliable for operating in air. Here, by using ultrathin Si3N4 as a physical isolation layer, we have obtained a robust memristive device based on SiO2 trapping although operating in air. Further study of Si3N4 thickness dependence has demonstrated that 7 nm is suggested as the most favorable thickness for reliable and flexible programming, and that an inherent isolating mechanism is ‘switching-on’ for an electron but ‘switching-off’ for large-sized oxygen molecules. Based on a device with 7 nm Si3N4, we have mimicked various modes of synaptic plasticities. These results could thus not only increase the prospects of using SiO2 trapping in memristive applications but also provide an effective path to improve the robustness of these SiO2-based applications against ambient air.
Phase noise matching in resonant metasurfaces for intrinsic sensing stability
Authors: Barth Isabel , Conteduca Donato , Dong Pin , Wragg Jasmine , Sahoo Pankaj K. , Arruda Guilherme S. , Martins Emiliano R. , Krauss Thomas F.
Published: January 2024

Interferometry offers a precise means of interrogating resonances in dielectric and plasmonic metasurfaces, surpassing spectrometer-imposed resolution limits. However, interferometry implementations often face complexity or instability issues due to heightened sensitivity. Here, we address the necessity for noise compensation and tolerance by harnessing the inherent capabilities of photonic resonances. Our proposed solution, termed “resonant phase noise matching,” employs optical referencing to align the phases of equally sensitive, orthogonal components of the same mode. This effectively mitigates drift and noise, facilitating the detection of subtle phase changes induced by a target analyte through spatially selective surface functionalization. Validation of this strategy using Fano resonances in a 2D photonic crystal slab showcases noteworthy phase stability (σ<10−4π). With demonstrated label-free detection of low-molecular-weight proteins at clinically relevant concentrations, resonant phase noise matching presents itself as a potentially valuable strategy for advancing scalable, high-performance sensing technology beyond traditional laboratory settings.
Single-peak and narrow-band mid-infrared thermal emitters driven by mirror-coupled plasmonic quasi-BIC metasurfaces
Authors: Yang Sen , He Mingze , Hong Chuchuan , Nordlander Josh , Maria Jon-Paul , Caldwell Joshua D. , Ndukaife Justus C.
Published: January 2024

Wavelength-selective thermal emitters (WS-EMs) hold considerable appeal
due to the scarcity of cost-effective, narrow-band sources in the
mid-to-long-wave infrared spectrum. WS-EMs achieved via dielectric
materials typically exhibit thermal emission peaks with high quality
factors (Q factors), but their optical responses
are prone to temperature fluctuations. Metallic EMs, on the other
hand, show negligible drifts with temperature changes, but their Q factors usually hover around 10. In
this study, we introduce and experimentally verify an EM grounded in
plasmonic quasi-bound states in the continuum (BICs) within a
mirror-coupled system. Our design numerically delivers an
ultra-narrowband single peak with a Q factor of approximately 64 and
near-unity absorptance that can be freely tuned within an expansive
band of more than 10 µm. By introducing air slots symmetrically, the Q factor can be further augmented to
around 100. Multipolar analysis and phase diagrams are presented to
elucidate the operational principle. Importantly, our infrared
spectral measurements affirm the remarkable resilience of our designs’
resonance frequency in the face of temperature fluctuations over
300°C. Additionally, we develop an effective impedance model based on
the optical nanoantenna theory to understand how further tuning of the
emission properties is achieved through precise engineering of the
slot. This research thus heralds the potential of applying plasmonic
quasi-BICs in designing ultra-narrowband, temperature-stable thermal
emitters in the mid-infrared. Moreover, such a concept may be
adaptable to other frequency ranges, such as near-infrared, terahertz,
and gigahertz.
MEMS-integrated metasurfaces for dynamic linear polarizers
Authors: Deng Yadong , Meng Chao , Thrane Paul C. V. , im Sande Sören , Bozhevolnyi Sergey I. , Ding Fei
Published: January 2024

Optical metasurfaces (OMSs), planar arrays of meticulously designed meta-atoms, are renowned for remarkable capabilities in manipulating the polarization state of light at subwavelength scales. Nevertheless, most OMS-empowered polarization optics remain static, featuring well-defined optical responses determined by their configurations set during fabrication. Here, we demonstrate a MEMS-OMS-based dynamic linear polarizer (DLP) with an electrically controlled extinction ratio, which is tunable in a fast and reversible fashion, by combining an anisotropic plasmonic OMS with a thin-film piezoelectric MEMS mirror. Capitalizing on the MEMS-OMS DLP, we further implement voltage-controlled grayscale imaging and vector vortex beam generation under linearly and circularly polarized excitations, respectively. Our MEMS-OMS DLP design could enable adaptive photonic systems for advanced applications in optical image encryption, displays, and beyond.
FindAdapt: A python package for fast and accurate adapter detection in small RNA sequencing
Authors: Chen Hua-Chang , Wang Jing , Shyr Yu , Liu Qi
Published: January 2024

Adapter trimming is an essential step for analyzing small RNA sequencing data, where reads are generally longer than target RNAs ranging from 18 to 30 bp. Most adapter trimming tools require adapter information as input. However, adapter information is hard to access, specified incorrectly, or not provided with publicly available datasets, hampering their reproducibility and reusability. Manual identification of adapter patterns from raw reads is labor-intensive and error-prone. Moreover, the use of randomized adapters to reduce ligation biases during library preparation makes adapter detection even more challenging. Here, we present FindAdapt, a Python package for fast and accurate detection of adapter patterns without relying on prior information. We demonstrated that FindAdapt was far superior to existing approaches. It identified adapters successfully in 180 simulation datasets with diverse read structures and 3,184 real datasets covering a variety of commercial and customized small RNA library preparation kits. FindAdapt is stand-alone software that can be easily integrated into small RNA sequencing analysis pipelines.
Predicting primate tongue morphology based on geometrical skull matching. A first step towards an application on fossil hominins
Authors: Alvarez Pablo , El Mouss Marouane , Calka Maxime , Belme Anca , Berillon Gilles , Brige Pauline , Payan Yohan , Perrier Pascal , Vialet Amélie
Published: January 2024

As part of a long-term research project aiming at generating a biomechanical model of a fossil human tongue from a carefully designed 3D Finite Element mesh of a living human tongue, we present a computer-based method that optimally registers 3D CT images of the head and neck of the living human into similar images of another primate. We quantitatively evaluate the method on a baboon. The method generates a geometric deformation field which is used to build up a 3D Finite Element mesh of the baboon tongue. In order to assess the method’s ability to generate a realistic tongue from bony structure information alone, as would be the case for fossil humans, its performance is evaluated and compared under two conditions in which different anatomical information is available: (1) combined information from soft-tissue and bony structures; (2) information from bony structures alone. An Uncertainty Quantification method is used to evaluate the sensitivity of the transformation to two crucial parameters, namely the resolution of the transformation grid and the weight of a smoothness constraint applied to the transformation, and to determine the best possible meshes. In both conditions the baboon tongue morphology is realistically predicted, evidencing that bony structures alone provide enough relevant information to generate soft tissue.
Regulus infers signed regulatory relations from few samples’ information using discretization and likelihood constraints
Authors: Louarn Marine , Collet Guillaume , Barré Ève , Fest Thierry , Dameron Olivier , Siegel Anne , Chatonnet Fabrice
Published: January 2024

Motivation

Transcriptional regulation is performed by transcription factors (TF) binding to DNA in context-dependent regulatory regions and determines the activation or inhibition of gene expression. Current methods of transcriptional regulatory circuits inference, based on one or all of TF, regions and genes activity measurements require a large number of samples for ranking the candidate TF-gene regulation relations and rarely predict whether they are activations or inhibitions.

We hypothesize that transcriptional regulatory circuits can be inferred from fewer samples by (1) fully integrating information on TF binding, gene expression and regulatory regions accessibility, (2) reducing data complexity and (3) using biology-based likelihood constraints to determine the global consistency between a candidate TF-gene relation and patterns of genes expressions and region activations, as well as qualify regulations as activations or inhibitions.

Results

We introduce Regulus, a method which computes TF-gene relations from gene expressions, regulatory region activities and TF binding sites data, together with the genomic locations of all entities. After aggregating gene expressions and region activities into patterns, data are integrated into a RDF (Resource Description Framework) endpoint. A dedicated SPARQL (SPARQL Protocol and RDF Query Language) query retrieves all potential relations between expressed TF and genes involving active regulatory regions. These TF-region-gene relations are then filtered using biological likelihood constraints allowing to qualify them as activation or inhibition. Regulus provides signed relations consistent with public databases and, when applied to biological data, identifies both known and potential new regulators. Regulus is devoted to context-specific transcriptional circuits inference in human settings where samples are scarce and cell populations are closely related, using discretization into patterns and likelihood reasoning to decipher the most robust regulatory relations.
Inferred regulons are consistent with regulator binding sequences in E. coli
Authors: Qiu Sizhe , Wan Xinlong , Liang Yueshan , Lamoureux Cameron R. , Akbari Amir , Palsson Bernhard O. , Zielinski Daniel C.
Published: January 2024

The transcriptional regulatory network (TRN) of E. coli consists of thousands of interactions between regulators and DNA sequences. Regulons are typically determined either from resource-intensive experimental measurement of functional binding sites, or inferred from analysis of high-throughput gene expression datasets. Recently, independent component analysis (ICA) of RNA-seq compendia has shown to be a powerful method for inferring bacterial regulons. However, it remains unclear to what extent regulons predicted by ICA structure have a biochemical basis in promoter sequences. Here, we address this question by developing machine learning models that predict inferred regulon structures in E. coli based on promoter sequence features. Models were constructed successfully (cross-validation AUROC > = 0.8) for 85% (40/47) of ICA-inferred E. coli regulons. We found that: 1) The presence of a high scoring regulator motif in the promoter region was sufficient to specify regulatory activity in 40% (19/47) of the regulons, 2) Additional features, such as DNA shape and extended motifs that can account for regulator multimeric binding, helped to specify regulon structure for the remaining 60% of regulons (28/47); 3) investigating regulons where initial machine learning models failed revealed new regulator-specific sequence features that improved model accuracy. Finally, we found that strong regulatory binding sequences underlie both the genes shared between ICA-inferred and experimental regulons as well as genes in the E. coli core pan-regulon of Fur. This work demonstrates that the structure of ICA-inferred regulons largely can be understood through the strength of regulator binding sites in promoter regions, reinforcing the utility of top-down inference for regulon discovery.
Genetic drift promotes and recombination hinders speciation on holey fitness landscapes
Authors: Kalirad Ata , Burch Christina L. , Azevedo Ricardo B. R.
Published: January 2024

Dobzhansky and Muller proposed a general mechanism through which microevolution, the substitution of alleles within populations, can cause the evolution of reproductive isolation between populations and, therefore, macroevolution. As allopatric populations diverge, many combinations of alleles differing between them have not been tested by natural selection and may thus be incompatible. Such genetic incompatibilities often cause low fitness in hybrids between species. Furthermore, the number of incompatibilities grows with the genetic distance between diverging populations. However, what determines the rate and pattern of accumulation of incompatibilities remains unclear. We investigate this question by simulating evolution on holey fitness landscapes on which genetic incompatibilities can be identified unambiguously. We find that genetic incompatibilities accumulate more slowly among genetically robust populations and identify two determinants of the accumulation rate: recombination rate and population size. In large populations with abundant genetic variation, recombination selects for increased genetic robustness and, consequently, incompatibilities accumulate more slowly. In small populations, genetic drift interferes with this process and promotes the accumulation of genetic incompatibilities. Our results suggest a novel mechanism by which genetic drift promotes and recombination hinders speciation.
Updating estimates of Plasmodium knowlesi malaria risk in response to changing land use patterns across Southeast Asia
Authors: Tobin Ruarai J. , Harrison Lucinda E. , Tully Meg K. , Lubis Inke N. D. , Noviyanti Rintis , Anstey Nicholas M. , Rajahram Giri S. , Grigg Matthew J. , Flegg Jennifer A. , Price David J. , Shearer Freya M.
Published: January 2024

Background

Plasmodium knowlesi is a zoonotic parasite that causes malaria in humans. The pathogen has a natural host reservoir in certain macaque species and is transmitted to humans via mosquitoes of the Anopheles Leucosphyrus Group. The risk of human P. knowlesi infection varies across Southeast Asia and is dependent upon environmental factors. Understanding this geographic variation in risk is important both for enabling appropriate diagnosis and treatment of the disease and for improving the planning and evaluation of malaria elimination. However, the data available on P. knowlesi occurrence are biased towards regions with greater surveillance and sampling effort. Predicting the spatial variation in risk of P. knowlesi malaria requires methods that can both incorporate environmental risk factors and account for spatial bias in detection.

Methods & results

We extend and apply an environmental niche modelling framework as implemented by a previous mapping study of P. knowlesi transmission risk which included data up to 2015. We reviewed the literature from October 2015 through to March 2020 and identified 264 new records of P. knowlesi, with a total of 524 occurrences included in the current study following consolidation with the 2015 study. The modelling framework used in the 2015 study was extended, with changes including the addition of new covariates to capture the effect of deforestation and urbanisation on P. knowlesi transmission.

Discussion

Our map of P. knowlesi relative transmission suitability estimates that the risk posed by the pathogen is highest in Malaysia and Indonesia, with localised areas of high risk also predicted in the Greater Mekong Subregion, The Philippines and Northeast India. These results highlight areas of priority for P. knowlesi surveillance and prospective sampling to address the challenge the disease poses to malaria elimination planning.
Evolution of the global terrorist organizational cooperation network
Authors: Cui Donghao , Ou Chaomin , Lu Xin
Published: January 2024

Terrorism has shown a trend of organizational cooperation in a large number of terrorist attacks around the world, posting a great challenge to counter-terrorism efforts. To investigate the trend and pattern of global terrorist organizational cooperations and to propose effective measures for effectively enforcing and restricting terrorist attacks, based on the Global Terrorism Database and the UN sanctions list of terrorist groups, this study constructs a cooperative evolutionary network of terrorist organizations from 119,803 terrorist attacks that occurred globally between 2001 and 2018. The evolution of worldwide terrorist cooperation is evaluated in terms of network characteristics, including key nodes, cohesion, and motifs. The network keeps expanding, with a large number of new nodes emerging each year. On average, there are 13 additional organizations entering in the collaboration network each year, with a yearly survival rate of about 34.66%, and the rank of node importance iterate and update frequently. Through k-core decomposition, for which the breakdown of the network has increased from three to five partitions, we find that the core of the terrorist organization’s cooperation network changes much less frequently than the edges. The dominating modal structure of the network is the "star" motif (90%), and "triadic closed" motif (9%). We conclude that, over time, the cooperative network of terrorist groups has gradually evolved into a cluster of star-shaped networks, with various organizations serving as the centers of the networks and showing core-periphery structure in their individual communities. The core organizations are highly connected and stable, whereas the periphery organizations are loosely connected and highly variable.
Information seeking behavior on hepatitis B virus, and its associated factors among pregnant women at teaching and specialized hospitals, Northwest Ethiopia: A cross-sectional study
Authors: Shibabaw Adamu Ambachew , Tegegne Masresha Derese , Walle Agmasie Damtew , Wubante Sisay Maru , Baykemagn Nebebe Demis , Sisay Melaku Molla , Weldeab Adane Nigusie
Published: January 2024

Introduction

Hepatitis B virus (HBV) infection continues to be a major public health issue worldwide. Health information-seeking behavior is critical to obtain information about health, diseases such as the Hepatitis B virus, health risks, and health promotion and it has become a major concern of health policymakers. However, there is little evidence of information-seeking behavior on the Hepatitis B virus in Ethiopia. So, this study aimed to assess Hepatitis B virus information-seeking behavior and its associated factors among pregnant women at teaching and Specialized Hospitals, in Northwest Ethiopia.

Methods

An institution-based cross-sectional study was conducted among pregnant women at teaching and specialized hospitals, in Northwest Ethiopia from May 01 to June 01, 2022. A total of 423 participants were selected using a systematic random sampling method. The data was collected through an interview-administered questionnaire by kobo-collect software. Then export into SPSS version 20 for analysis. Descriptive statistics, bi-variable, and multivariable logistic regression analyses were done to identify factors associated with Hepatitis B virus information-seeking behavior.

Results

The proportion of information-seeking behavior on the Hepatitis B virus among pregnant women was 40.5% (CI = 35.7, 45.6). Education(diploma and above) [AOR = 3.3, 95% CI (1.31, 8.16)], more than one ANC visit [AOR = 5.99, 95% CI (3.20, 12.31)], smart-phone ownership [AOR = 4.1, 95%CI (1.35, 12.31)], internet access [AOR = 5.1, 95%CI (1.35, 15.60)], perceived susceptibility [AOR = 2.7, 95%CI (1.38, 5.31)], perceived severity [AOR = 3.7, 95%CI (2.06, 6.55)], and self-efficacy [AOR = 1.9, 95%CI (1.03, 3.73)] were factors influencing information seeking on Hepatitis B virus.

Conclusion

The overall proportion of information-seeking behavior on HBV among pregnant women was low. To improve information-seeking behavior on HBV among pregnant women we should connect the women to the internet and technology. Creating women’s awareness about the Hepatitis B virus severity and their venerability and increasing their antenatal care (ANC) visits, self-efficacy, internet access, and women’s education can improve information seeking about the Hepatitis B virus.