bluuebunny/crossref_metadata_2025 huggingface dataset:
Accountability Advocates: Representing Victims
Authors: White Sabrina
Published: January 2025

This chapter contributes to critical reflections on the political meanings embedded in claims to represent victims and survivors of sexual exploitation and abuse (SEA) and the nature of the platforms meant to share their voices. It problematizes the role of victims’ rights advocates in light of the United Nations (UN’s) victim-centred approach to SEA. It reflects on the constitution of the political space within which UN advocacy on SEA emerged from 2004 to 2021, analysing how victims have been discursively represented in official UN policy documents. It then explores the status of the practice of the victim-centred approach through the work of the Office of the Victims’ Rights Advocate. The author argues: first, that advocating on behalf of victims/survivors and paternity claimants is restricted conceptually and practically by the limited political will evidenced by the underprioritization of resourcing for and access to complaints mechanisms and support; and, second, that the UN’s new advocacy efforts are both necessary for advancing political will and a problematic filter through which the voices of victims, survivors, children fathered by peacekeepers and the mothers of those children are heard.
Power, Consent and Peacekeeping Economies
Authors: Jennings Kathleen M.
Published: January 2025

This chapter problematizes how the United Nations’ zero-tolerance policy (ZTP) against sexual exploitation and abuse represents the notion of consent by both peacekeepers and ‘beneficiaries of assistance’. I argue that the ZTP writes into regulation narrow understandings of sexual intimacy against puritanical and contested conditions for consent, in contexts characterized by complex power relations between interveners and residents. However, this assumption of where power lies and how it operates does not always map onto peacekeepers’ and local residents’ experiences and interactions. This has the potential effect of undermining the ZTP’s legitimacy and complicating its implementation.
Gender, Race, Sexuality and PSEA
Authors: Bian Junru , Daigle Megan , Martin Sarah , Myrttinen Henri
Published: January 2025

Since the 2018 Oxfam sexual abuse scandal, many new protection from sexual exploitation and abuse (PSEA) initiatives were launched to address an endemic problem in the humanitarian sector. The same year, revelations of sexual harassment inside Save the Children sparked the #AidToo movement, which highlighted abuses against aid workers themselves. Amid ongoing efforts to decolonize and rebuild a more just aid sector, the authors consider whose protection really matters, who gets to define PSEA, and how committed the humanitarian sector is to achieving it. ‘Local culture’ is much discussed in this context, but how the colonial, patriarchal and heteronormative foundations of the mainstream humanitarianism system enable abuse and stall meaningful change is much less discussed. The authors argue that the dominant self-image of the humanitarian sector and its formal and informal institutional cultures stand in the way of serious preventing sexual exploitation, abuse and harassment committed by humanitarians, be it against intended beneficiaries or their own colleagues. We suggest that PSEA efforts must go far beyond trainings and guidelines, and instead address fundamental gendered and racialized power imbalances, practices and structures in the humanitarian sector.
‘We Don’t Have a Word for That’: Issues in Translating PSEA Communication
Authors: Elderfield Emily , Kemp Ellie
Published: January 2025

Organizations rarely adequately factor language into the design of protection from sexual exploitation and abuse (PSEA) interventions. Yet people talk about sex and sexual abuse in different ways between cultures, contexts and even groups within the same community. Power dynamics related to language marginalization also deter survivors from reporting. In some highly segregated communities or among excluded groups, people may use coded terms where being understood by others presents a risk to their safety. And interventions focused largely on reaching adult women reinforce barriers for men, children and adolescents to report or seek protection from abuse. Understanding how to listen effectively to survivors and communities is the critical first step that will help organizations overcome what is lost in translation in current global PSEA approaches. In this chapter, the authors synthesize evidence from several humanitarian contexts to discuss language and communication barriers in information campaigns and reporting mechanisms, how language choices impact discussions of transactional sex and contextual drivers of sexual exploitation and abuse and harassment, and how language awareness supports inclusive prevention efforts.
From ‘Cultural Sensitivity’ to ‘Structural Sensitivity’
Authors: Abu-Assab Nour
Published: January 2025

This chapter proposes the need for a paradigm shift from ‘cultural sensitivity’ to ‘structural sensitivity’ in safeguarding frameworks. It is argued that although international organizations claim that their safeguarding systems are culturally sensitive, those systems are usually built around the experience of those inside the international organizations and fail to take understandings of local contexts and dynamics into account. This poses an obstacle to addressing sexual exploitation and abuse (SEA), with instances of abusive and oppressive practices such as gender-based discrimination being dismissed or justified under the umbrella of cultural sensitivity. It also silences victims and survivors and creates barriers to restorative and transformative justice processes. A shift in focus from cultural sensitivity to structural sensitivity would allow for a more effective response to abusive practices within organizational structures by taking into account a broader set of factors that often create or exacerbate SEA contexts.
Classifying Colonial Crime: Seven Deadly Sins
Authors: Castellino Joshua
Published: January 2025

Colonial history is so diverse and its devastation so widespread that it is often deemed too complex to discuss as a single phenomenon. This chapter, based on historical and contemporary readings of challenges in a range of societies that came under colonial influence, traces patterns across this vast edifice in a bid to offer a typology of the phenomenon. It identifies seven broad categories, including crimes committed in the process of territorial acquisition and during colonial rule, and others that contribute to the maintenance of colonial hegemonies post decolonization.
Financing System Change: A Recovery-Based International Law Response to Colonial Crime
Authors: Castellino Joshua
Published: January 2025

The scale of finance required for the sharp systemic change needed is referenced as a brake on why system change is difficult to achieve. This chapter advocates a perpetrator-based rather than victim-centred approach, that calls for tracking extracted wealth that drove environmental damage by mainstreaming the crime of unjust enrichment that already exists within legal systems. Extending this to tackling unfairly accumulated wealth that transferred into private hands during and after the colonial era, not least to shareholders and executives of extractive industries would stop harmful activities, strike a blow for justice, fund the transition and lay down a clear marker for acceptable economic behaviour within a sustainable society.
From Vicious Cycle to Virtuous Circle
Authors: Castellino Joshua
Published: January 2025

This concluding chapter identifies ten statements that characterize the international financial architecture. It argues these animate a vicious cycle that enable impunity for the climate and social crises. The chapter addresses how this cycle can be disrupted by halting specific economic activities, addressing colonial and contemporary crimes, unlocking wealth and looking beyond sovereign States that are deeply implicated in the problem and therefore resistant to change. It demonstrates how a virtuous cycle can be constructed through situation-specific pragmatic collaboration and cooperation across national boundaries in a world composed of 16 inhabited regions.
Nozick, the Pandemic and Fear: A Contractualist Justification of the COVID-19 Lockdown
Authors: Moser Elias
Published: January 2025

As a reaction to COVID-19, many democratic countries around the world imposed a curfew on their entire population. Schools, shops, public and private buildings were shut down while all forms of public assembly were temporarily banned. Strong restrictions were imposed on liberties in many domains of the quotidian life of citizens to preclude a collapse of the health system. From the perspective of political philosophy, the normative legitimacy of lockdown policies needs to be investigated. Under which conditions can large-scale interventions in the private and public spheres be justified? In this chapter, I discuss contractualist political theory as a potential framework for assessing the restrictions as a response to the menace of a global pandemic. I will apply the reflections of Robert Nozick in the first part of his famous Anarchy, State, and Utopia. His reflections on how a society should deal with risks are of great value in assessing policies to combat the spread of viruses. Nozick introduces a surprising element in his theory that is an important factor for a potential justification of lockdown policies - the incidence of fear. Because people are afraid of the worst outcome, they are willing to prohibit conduct that includes risks, and they are willing to restrict their own liberty to engage in that conduct.
The Pandemic, Freedom and Fear: A Reply to Moser
Authors: Jones Peter
Published: January 2025

Elias Moser (2021) takes on a challenging task. He aims to show that we can derive from Robert Nozick's natural rights theory, and its associated contractarianism, a justification for the lockdowns that governments have used to contain the current pandemic. Lockdowns have been controversial. They have provoked loud and vigorous complaints from some quarters that they deprive people, unnecessarily and unjustifiably, of several of their fundamental liberties and Nozick's Anarchy, State, and Utopia (1974), with its defence of the minimal state, is just the sort of text to which we might expect the protestors to turn for support. Showing that lockdowns can find a defence in the foundations of Nozick's libertarianism is therefore no mean task. A commentator on Moser's argument might begin by challenging the Nozickian premises on which it depends. That is not a path I shall take. Nozick's thinking is highly controversial but, even if we dissent from it, there is much we can learn from his penetrating and intricate analysis of the issues we confront when we strive to reconcile people's liberties with the threats and insecurities they may face. He presents his analysis as part of hypothetical history that plots the way in which individuals might move out of a state of nature and into a minimal state while suffering no violation of their natural rights; in truth, however, much that he has to say in Part I of Anarchy, State, and Utopia has a much larger compass. It can be exploited for its relevance.
A Reply to Castration Anxiety, COVID-19 and the Extremist Right by Claudia Leeb
Authors: McAfee Noëlle
Published: January 2025

Claudia Leeb's important essay, 'Castration anxiety, COVID-19 and the extremist right' (2021), contributes to our growing understanding of the logics of right-wing populism and conspiracy theories, here as exemplified by former US President Donald Trump's and Austrian politician Norbert Hofer's responses to the COVID-19 pandemic. Both Trump and Hofer have portrayed themselves as more powerful than the virus and the virus as nothing to fear, encouraging their followers to disregard public health measures as they are unnecessary and emasculating. Leeb draws on Theodor Adorno's 1967 lecture, Aspekte des Neuen Rechtsradikalismus (Aspects of New Right Extremism; republished in 2019), for a psychoanalytic account of the castration anxieties that COVID-19 has provoked. Closer to Lacan's rather than Freud's account, castration here means being metaphorically 'cut down to size', diminished, a subject with a hole at its centre that, having entered the symbolic realm, will always suffer from a lack and incessant but elusive desire for wholeness. Anyone who has entered into the Symbolic, trading away presence for representation is, as Calvin Thomas puts it, suffering from 'symbolic castration,' which 'is for Lacan the universal condition of anyone who speaks' (Thomas, 2019: 134). With Adorno, Leeb sees castration further as a matter of capitalism's 'mutilating conditions', which, with the pandemic, have led to castration anxieties over economic precarity, interpersonal isolation and personal bodily health; as well as how COVID-19 has left many people vulnerable to the lure of the culture industry, especially through the internet, leading to diminished critical thinking and heightened vulnerability to being captured by far right extremism.
Fear and the Importance of Race-Based Data in COVID-19 Policy Implementation
Authors: Harper Leland
Published: January 2025

This chapter distinguishes between the experiences of Black Americans and white Americans during the COVID-19 pandemic and how this different experience relates to fear. This chapter ultimately argues that policymakers ought to fund the collection and analysis of race-based data, as it pertains to COVID-19, and that these policymakers ought to appeal to the findings of this race-based data to guide their policy and implementation strategy. Without gathering or appealing to such data, policymakers are being negligent in working to protect their constituents.
Lockdown: A Case Study in How to Lose Trust and Undermine Compliance
Authors: Faulkner Paul
Published: January 2025

To protect against COVID-19, the UK Government imposed a national lockdown that shut schools and business, and required people to stay at home. This lockdown instituted a social coordination problem: it demanded the individual bear a cost - a significant restriction to their movement - in order to achieve a collective good. Initially there were remarkably high levels of social compliance with the lockdown restrictions, but the Government defense of Mr. Cummings corresponded with a notable drop in both levels of compliance and levels of trust in government. By considering the logic of social coordination problems, this chapter offers an explanation as to why these drops in compliance and trust were to be expected.
Relevancia e injerencia política del poder democrático en la épica arcaica: un abordaje desde el pensamiento homérico
Authors: Prada Gastón Alejandro
Published: January 2025

Existe entre los historiadores un consenso generalizado en que el advenimiento de la democracia griega se dio a partir de la transformación de las prácticas y el espacio plebiscitarios del período arcaico en una configuración más estable y lógico-jurídica del oficio y de la ley que tiene lugar en la Atenas clásica. Estas dinámicas asamblearias constituyen uno de los pilares fundamentales de la narrativa homérica, lo que ha sugerido que la Ilíada y la Odisea expresan la mentalidad igualitaria y protodemocrática griega. Sin embargo, se ha sostenido que el pueblo conlleva una atenuada injerencia política, en tanto que solo condiciona exiguamente o, a lo sumo, sirve como un órgano consultivo. Este artículo analiza el abordaje filosófico-político de los problemas presentados en los poemas homéricos en torno a una concepción democrática del ejercicio soberano. Se pretende mostrar el planteo y posicionamiento de la épica homérica en torno al poder democrático no tanto desde una perspectiva ideológica, sino más bien desde mirada problematizante. Esto es: puede advertirse en los poemas un intento de reflexión filosófico-política por parte del poeta sobre la relevancia, los alcances, los límites y las tensiones que presentan las prácticas políticas y sociales que pueden denominarse “democráticas”.
La còpia aramea de la inscripció de Bisitun revisitada: una narració de l'ascens de Dàrius des d'Elefantina
Authors: Martín Pons Jordi
Published: January 2025

Amb aquest article fem una aproximació a la versió aramea de la Inscripció de Bisitun, tot proposant-ne una traducció en llengua catalana i analitzant la seva importància i la seva història. Aquesta versió, que es compta entre els papirs arameus d’Elefantina, datats en l’època aquemènida d’Egipte, i en el context d’aquella comunitat jueva al Nil, ens permetran accedir a un conjunt d’informacions molt valuoses sobre el judaisme pre-exílic i pre-bíblic. Podrem analitzar una comunitat jueva a Egipte a través de la seva realitat filològica, cultural i religiosa i capir la manera en la qual van entendre el seu paper dintre del nou esquema aquemènida creat a partir de la mort de Cambises i el tumultuós ascens de Darios I.
crítica macrofilosófica de Adorno a Hegel
Authors: Picuș Leonard
Published: January 2025

Un modelo de la macrofilosofía es un intento de pensar la unidad de la filosofía, su actualidad para la cultura universal. Filosofía, como cualquier forma creativa de cultura, es un conocimiento en evolución, que puede ser apreciado según su capacidad de reflejar el espíritu humano. Un tal modelo macrofilosófico mediría, también, la evolución de la forma de la filosofía y tendría la relevancia de una metafilosofía. La macrofilosofía de G. Mayos supone la razón dialéctica; por consiguiente, la determinación de lo dialéctico prepara la reflexión sobre la cualidad dialéctica del concepto en macrofilosofía. G. Mayos ve en la dialéctica hegeliana un paradigma para la macrofilosofía, porque es una dialéctica del concepto, adecuada para un pensamiento filosófico macrocategorial. Por otra parte, dos problemas básicos determinan la actitud filosófica de Adorno frente a la filosofía de Hegel: el concepto dialéctico y la relación espíritu-individuo. El pensamiento filosófico es modelo, pero el objeto de este modelo es inmanente, porque, para Adorno, todo es socialidad. Sin embargo, el sentido de la crítica que Adorno hace a Hegel es macrofilosófico. A partir de todas estas consideraciones, propondremos un modelo disciplinario de la macrofilosofía y, en consecuencia, un debate para una teoría actual de la razón dialéctica.
Visita de indios y expedientes judiciales en el Nordeste del Río de la Plata: Corrientes, siglo XVII
Authors: Valenzuela Fatima , Salinas María Laura
Published: January 2025

Una tarea vinculada a la digitalización y catalogación del fondo judicial del Archivo General de la Provincia de Corrientes (Argentina) permitió hallar y recuperar fuentes de significativo valor histórico para la historia de la población de la región nordeste del Río de la Plata. Las fuentes encontradas fueron dos visitas de indios que se desarrollaron en 1671 y 1672 por petición del gobernador de Buenos Aires a los funcionarios locales. Para contextualizarlas, el trabajo recuperará las fuentes demográficas conocidas y trabajadas por la historia de la población en el territorio correntino de los siglos XVII y XVIII. Luego el análisis se orientará a presentar y caracterizar el fondo judicial del archivo mencionado, para centrarnos en las visitas de 1671-1672 analizando su origen, su naturaleza, los actores intervinientes y los datos demográficos que arrojan estas fuentes.
La moral pública y el Estado en Paraguay a mediados del siglo XIX
Authors: Potthast Barbara
Published: January 2025

En este artículo, debatimos el carácter del Estado paraguayo a mediados del siglo XIX bajo la perspectiva de su política administrativa y sociocultural a partir de regulaciones estatales, pleitos judiciales y datos demográficos.  Analizamos la voluntad del presidente Carlos Antonio López de reconstruir el poder de la Iglesia y de hacer de esta un agente importante en su objetivo de fortalecer el Estado patriarcal. Su intento de mejorar la «moral pública» y el comportamiento sexual de la población no tuvo, sin embargo, mucho éxito. No obstante, los altos números de hijos ilegítimos y de mujeres cabeza de familia no desmienten el carácter patriarcal de las estructuras familiares y de la sociedad paraguaya.
La quimera de la igualdad. Algunas puntualizaciones sobre afrodescendencia, derechos y racismo estructural en Buenos Aires (1873-presente)
Authors: Geler Lea
Published: January 2025

En este artículo esbozaré unas breves reflexiones acerca de la compleja relación histórica entre derechos, racismo y afroargentinidad en Buenos Aires, desde 1870 hasta la actualidad, a partir de argumentos surgidos principalmente de mis propias investigaciones histórico-antropológicas. Los objetivos son mostrar que la relación entre derechos e igualdad no es transparente, exhibir la pervivencia del racismo en la ciudad (racismo estructural) y poner de relieve la importancia de contar con investigaciones que se centren en las vivencias, acciones y discursos de quienes soportan las consecuencias de la desigualdad racializada.
evolució de les tècniques de pesca al llevant espanyol i la comercialització del peix fresc a la ciutat de Barcelona: 1890-1930
Authors: Muntané i Pueyo Daniel
Published: January 2025

A inicis del segle xx la majoria de la pesca capturada arreu del litoral català s’enviava a la ciutat de Barcelona. La millora en els mitjans de transport i els avenços en els sistemes de conservació, així com l’evolució de les tècniques de pesca en el llevant espanyol, facilitaven la comercialització del peix fresc cap a la capital catalana. Al mateix temps, aquesta concentració de la pesca afavoria directament els intermediaris establerts a la ciutat, que especulaven amb el preu del peix segons l’hora d’arribada i el volum de les captures.
Curatorial Activism and Practices of Listening: Revisiting Kuratorisk Aktion’s Rethinking Nordic Colonialism (2006)
Authors: Ellegaard Line
Published: January 2025

This article critically discusses the collective and collaborative curatorial practice of Kuratorisk Aktion, consisting of Danish curators Fred (previously Frederikke) Hansen and Tone Olaf Nielsen, though the case of their first exhibition project Rethinking Nordic Colonialism: A Postcolonial Exhibition Project in Five Acts (2006). The exhibition was a pioneering effort, which addressed systemic discrimination and racial silences in relation to minorities and Indigenous people in the Nordic region, through a focus on amnesia in the collective memory around Nordic colonial history. This article examines how the white Danish curators addressed and negotiated asymmetrical power relations between Denmark and Greenland, as well as asymmetries in relation to their own practice as curators and their position as Danes. Further, it analyses how the project assembled practicians from both the so-called Global North and the Global South, to enhance strategies of resistance across geographical divides and create alliances of solidarity across common differences, as suggested by feminist theorist Chandra T. Mohanty (2003). Through this historical example, the article contributes to ongoing discussions of creative forms of resistance, and alliances between arts and social movements in which assemblies and gatherings form generative strategies. This case study suggests how curatorial activism seeking to prevent forms of cognitive extractivism might be understood in relation to practices of listening, whilst reflecting on issues of privilege and authorship in collective and collaborative practices.
Aprender desde la práctica: ecofeminismo y procesos artísticos colectivos. Una conversación con LaFundició
Authors: Sgaramella Chiara , Rubio Francisco
Published: January 2025

Chiara Sgaramella conversa con Francisco Rubio, integrando de LaFundició, una cooperativa creada en 2006 que impulsa procesos colectivos de construcción de conocimiento, prácticas culturales y formas de relación, entendidos como recursos de uso común. El diálogo se centra en las principales ideas y motivaciones que mueven el colectivo artístico, su implicación en el territorio de l'Hospitalet de Llobregat (Barcelona), y profundiza en el análisis de algunas iniciativas culturales como el proyecto de producción agroecológica y simbólica Las Cabasses.
What's in a Name?: Naomi Shihab Nye's "Blood" and the Unspeakable Ordeal of the Real; A Lacanian Reading
Authors: Abouddahab Redouane
Published: January 2025

Abstract: "Blood" celebrates the possibility of overcoming the experience of ethnic othering, thanks to the symbolizing process undertaken by the speaker's father, a Palestinian refugee. Naomi Shihab Nye thus underscores the efficiency of the Symbolic and the liberating potentialities of the Imaginary. Yet, the poem introduces a dialectical reversal as the symbolic structure put in place by the Shihabs is threatened with collapse by the disruptive forces of the Real. The sociopsychological family portrait Nye's poem is focused on can thus be understood in broader terms as a composite of systems put under tension and stabilized through writing. The testimonial task of this Arab American poet is coupled with the necessity to repair a deficiency in the relation between the Real, the Symbolic, and the Imaginary. Poetically examining the paternal function gives the daughter the possibility to repair a flaw in structure, and to probe the ontological knot that constitutes the human subject.
Fabrication of micro-bulge structures by a chemically assisted spatially shaped femtosecond laser and investigation of their surface anti-icing performance
Authors: Wang Yang , Wang Qian , Yuan Yanping
Published: January 2025

To address the anti-icing performance requirements of superhydrophobic surfaces, this study adopts a manufacturing method that combines Bessel femtosecond laser and chemical modification techniques to fabricate a superhydrophobic micro-protrusion structure on a nickel-based high-temperature alloy surface. The micro-protrusion structure consists of micro-scale elevations and nano-scale wrinkles, which results in a contact angle as high as 152.4∘±0.1∘. This allows the static freezing time of the surface to be extended from 31 to 228 s, which is 7.3 times longer than the untreated nickel-based alloy sample. This is because the micro-protrusion structure, in collaboration with the silanization modification technique, significantly reduces the surface-free energy of the material, which can effectively regulate the wettability of the material surface, transitioning it from hydrophilic to superhydrophobic. This study provides a new approach for anti-icing technology, to our knowledge, that can be widely applied in the fields of energy, military, and aerospace.
In-situ holographic characterization of thin liquid film thickness evolution during boundary-constrained motion
Authors: Wang Zhe , Ferraro Vincenzo , Maffettone Pier Luca , Coppola Sara
Published: January 2025

Digital holography, a remarkably effective tool for in-situ measurements of thin liquid film thickness, was employed to investigate the evolution of a vertically moving soapy water film under boundary constraints. Our comprehensive experiments, conducted across four distinct pumping rates, unveiled the intricate process of central thinning and accurately measured its expansion rate through a rigorous spatiotemporal analysis. To address the complexities of asymmetric flow motion, we developed a novel diagonal spatiotemporal analysis strategy, to our knowledge, that significantly enhanced the precision and accuracy of our findings.
Polarization beam splitter based on a double-groove slanted grating under normal incidence
Authors: Wang Yi-han , Wang Jin , Chen Yu-da , Huang Zhi-sen , Jia Wei , Zhou Chang-he
Published: January 2025

In this paper, we propose a one-dimensional polarization beam splitting grating under normal incidence with excellent polarization characteristics and a high diffraction efficiency. The main structure is a double-groove slanted grating. We employed a rigorous coupled-wave analysis and simulated annealing algorithm for numerical calculations of the grating. The optimized grating structure can concentrate the energy of TE-polarized light at the −1st order and the energy of TM-polarized light at the 0th order under normal incidence. The analysis results indicate that at the incident wavelength of 1550 nm, the diffraction efficiency is 93.549% for TE polarization and 93.522% for TM polarization, with an extinction ratio greater than 14 dB. To the best of our knowledge, this is the first report of a one-dimensional polarization beam splitter grating with a transmissive double-groove slanted grating under normal incidence. This grating shows great potential for applications in polarization measurement, imaging, and grating encoders.
Phase-limited quantization-aware training for diffractive deep neural networks
Authors: Wang Yu , Sha Qi , Qi Feng
Published: January 2025

In recent years, all-optical diffractive deep neural networks (D2NNs) have demonstrated exceptional performances in many fields. Discretizing the grating height can reduce the complexity and enhance the network manufacturing efficiency. For this purpose, we propose a phase-limited quantization-aware training (PLQAT) method and construct an all-optical D2NN to discretize the network for the MNIST image classification task. Our results indicate that the PLQAT method improves the classification performance of the D2NN by 0.11–27.96% across different bit levels compared to the classical algorithm. Furthermore, we identified 3-bit quantization as the optimal choice, discretized the phase values in five layers to eight levels within [0,2π], and achieved a test accuracy of 96.22%. This method discretizes the height of gratings of D2NNs, effectively reducing the difficulty of grating etching while maintaining good network performance.
Narrowband reflector based on a side-coupled transverse-mode-conversion Bragg grating resonator
Authors: Shen Jixiang , Zhao Yong , Wang Ruxin , Zhao Dehui , Ni Yi
Published: January 2025

We propose a narrowband reflector (NBR) on the Si3N4 platform based on a side-coupled transverse-mode-conversion Bragg grating resonator. The NBR is constructed of the bus waveguide consisting of two S-bends, and the resonator waveguide consisting of two anti-symmetric Bragg gratings (ASBGs) and a uniform Bragg grating (UBG). Due to the support of UBG, two ASBGs can form two resonant modes, in which the fundamental transverse electric (TE0) and the first order transverse electric (TE1) modes are interconnected in different propagation directions. The backward TE1 mode can be coupled to the bus waveguide and converted to TE0 mode, resulting in reflection at the input port. The proposed NBR does not require tuning with the Vernier effect. The reflection spectrum is not Lorentzian in shape. It can achieve a box-like reflection spectrum when the resonant splitting is introduced. The NBR remains effective even when the laser wavelength undergoes slight chirping. The proposed NBR can serve as an external cavity for emitting narrow linewidth lasers at specific wavelengths. The simulation results demonstrate that the reflection of 0.829 (−0.814dB), full width at half maximum (FWHM) of 0.34 nm, and side lobe suppression ratio (SLSR) of 44 dB are achieved for the proposed reflector when the grating length is 476.8 µm.
Particle positioning and characterization using wavefront curvature with a convolutional neural network in digital holography
Authors: Hasegawa Shin-ya , Nakashige Shota
Published: January 2025

Accurately and simultaneously determining the axial position, radius, and refractive index of spherical particles remains challenging in digital holography (DH). Applications such as fluid dynamics, fuel droplet evaporation, and aerosol characterization often require low-numerical-aperture (NA) optical setups to capture a broad field of view. However, the reduced number of interference fringes hinders accurate parameter estimation using conventional holographic interference pattern analysis. To address this limitation, we present a method that employs a one-dimensional convolutional neural network trained on wavefront curvature profiles along the optical axis. This approach enables the accurate and simultaneous determination of all three parameters for low- and high-NA systems. In a low-NA (0.02) setup, our method achieves accuracies of 0.3%, 2.0%, and 7.0% for radius, axial position, and refractive index estimation, respectively, outperforming conventional methods. Experimental validation confirmed the effectiveness of our approach, enhancing the capabilities of DH for particle characterization across diverse applications requiring any NA setup.
Diode-pumped Nd:YVO4 system for hundreds nanosecond high-power high beam quality laser generation
Authors: Yuan Junjie , Yang Houwen , Cheng Wenyong
Published: January 2025

In this study, we successfully developed a high beam quality Q-switched pulsed laser operating at a wavelength of 1064 nm, featuring a repetition frequency of 25 kHz and an power output of 150.2 W. The system comprises a seed laser oscillator coupled with a four-stage traveling-wave amplifier, utilizing Nd:YVO4 crystals as the medium for both oscillation and amplification stages. To mitigate the thermal effects on the crystal, we meticulously selected an appropriate laser diode (LD) wavelength, optimized the concentration and length of the crystals, and applied indium welding techniques. Additionally, we implemented thermal spherical aberration compensation to further enhance the beam quality and overall output power. We conducted an extensive analysis on the beam quality and amplification efficiency across each stage of the system. Ultimately, we achieved a frequency doubling power of 49 W using a type-I non-critical phase matching LiB3O5 crystal, resulting in a conversion efficiency of 32.6%. Our findings illustrate the viability of employing Nd:YVO4 crystals in multi-stage amplification setups to produce high-power lasers with pulse durations on the order of hundreds of nanoseconds.
Optimization of a weight matrix calculation for computed tomography of chemiluminescence imaging
Authors: Ren Chengsheng , Jin Yi , Zhai Chao , Sha Xinguo , Song Huazhen
Published: January 2025

Computed tomography of chemiluminescence (CTC) reconstructs unknown physical quantities in 3D fluids by capturing 2D projections, and the imaging model must accurately describe the mathematical relationship between the volume of interest (VoI) and the projections. This paper addresses the optimization of the weight matrix calculation in CTC imaging and introduces the Monte Carlo subpixel (MC-subpixel) method. The method is applied to dynamic imaging scenarios where frequent camera position adjustments are required, such as scenes with limited projection angles or opaque optical obstructions. It improves computational efficiency and maintains reconstruction accuracy. Simulative studies show that compared to subpixel segmentation methods, the MC-subpixel method maintains the same order of magnitude (approximately 0.05 s) per voxel computation time while reducing the reconstruction cumulative error by 41.39%. Additionally, compared to the voxel spread function (VSF) method, this algorithm reduces the time complexity by an order of magnitude while ensuring comparable reconstruction errors. Supported by this algorithm, 3D measurements of the Bunsen flame successfully yielded key parameters of flame combustion, including the 3D volume, surface area, and convexity. These measurements suggest the spatial structure, the evolution process of the flame growth, and the interaction between the flame and the flow.
Transformer-based self-supervised learning of pixel- and frequency-domain features for DMI grading on OCTA images
Authors: Chen Zailiang , Zhong Wenyan , Yu Feiyang , Shen Hailan , Meng Yongan , Xiong Wanqing , Luo Jing
Published: January 2025

Diabetic macular ischemia (DMI) is a critical vision-threatening complication of diabetic retinopathy. While optical coherence tomography angiography (OCTA) enables non-invasive DMI progression diagnosis, acquiring labeled datasets remains challenging. This study proposes a self-supervised learning framework for DMI grading that leverages both pixel- and frequency-domain features. By using a pixel-level transformer and global filter transformer, the approach extracts aggregated features from OCTA images through contrastive pretext tasks. Experimental validation on three retinal disease benchmarks demonstrates superior performance compared to state-of-the-art methods, with the framework showing promising capabilities in lesion area recognition and potential clinical diagnostic assistance.
Independently tunable dual-channel angle-sensitive narrow-band perfect absorber
Authors: Yang Qilong , Zeng Lili , Li Boxun
Published: January 2025

In this correspondence, we introduce a versatile adjustable absorber featuring two distinct channels. Its primary composition includes strontium titanate (STO) and graphene. The refractive index of STO is influenced by temperature variations and the existence of the structural cavity, allowing for dynamic regulation of the absorption spectrum through external temperature changes and the angle of incident light. The developed device is capable of achieving dual-channel narrow-band perfect absorption at frequencies of 0.394 and 1.24 THz, demonstrating absorption rates of 99% and 98%, respectively. Importantly, we examined the Fermi level transition from 0 to 0.5 eV, revealing that the first resonance absorption peak can be adjusted within a range of 60% to 99%, accompanied by a redshift. This phenomenon is attributed to the local surface plasmon resonance induced by the graphene layer. The absorption characteristics of the second resonance remain relatively stable due to the peak formations within the Fabry–Perot cavity situated inside the STO layer. Given that the formant is influenced by temperature, it can be utilized as a temperature sensor. Furthermore, the absorptivity can be modified by altering the angle of the incident light. As a result of this angle dependence, optical switching can be achieved with a 22 dB ON/OFF ratio and a modulation depth close to 100%. Due to the symmetry of the absorption structure, the device remains unaffected by the polarization of the incoming light. The proposed tunable absorber has potential applications in electromagnetic absorption, optical switching, and various other domains.
Design of on-chip coded X-ray sensors for high-confidence super-resolution radiological imaging
Authors: Mao Tianyi , Wang Lei , Jiang Yuqi , Ma Xu , Zhu Shujin , Dai Xiubin , Arce Gonzalo R.
Published: January 2025

Robustness and confidence are crucial
in super-resolution tasks for
X-ray radiological imaging, both in terms of X-ray sensors and image
processing techniques. Due to the extremely short wavelengths of
X-rays, optical modulation in X-ray imaging systems is highly
challenging. Consequently, single-image super-resolution techniques in
computer vision have become a popular approach in medical imaging.
However, these methods can lead to artifacts and the plasticity
phenomenon, potentially compromising image quality and diagnostic
accuracy. In this manuscript, we introduce an on-chip coded aperture
design that is both cost-effective and helps overcome the additional
constraints and limitations commonly found in traditional
computational-imaging-based super-resolution X-ray systems. This
design generates sub-pixel physical coding on X-ray sensors, and thus
a three-dimensional (3D) computational decoding approach is presented
that transforms the two-dimensional (2D) super-resolution
reconstruction into a 3D compressed sensing problem. Unlike
super-resolution restoration in computer vision, this problem can be
mathematically solved to yield interpretable reconstructions under the
constraints of the restricted isometry property. Our experimental
results, complemented by qualitative analysis, demonstrate the
superiority of our design in X-ray radiological imaging, effectively
mitigating artifacts and the “plastic-like” appearance frequently
associated with conventional super-resolution techniques.
Phase fusion in multi-frequency phase-shifting fringe projection profilometry for minimizing effects of random noise
Authors: Xie Tao , Guo Hongwei
Published: January 2025

In fringe projection profilometry, random noise is recognized as one of
the most crucial error-inducing factors. This paper presents a phase
fusion strategy for minimizing the effects of noise on measurement
results in multi-frequency phase-shifting profilometry. The
multi-frequency profilometry captures several sequences of
phase-shifted fringe patterns with different fringe frequencies for
phase-unwrapping purposes. In it, the phase map of a lower-frequency
fringe pattern has a larger unambiguous phase range, thus being used
to form a reference for unwrapping the phases of a higher-frequency
fringe pattern, and only the phases of the highest-frequency fringe
pattern are retained as the final phase-measuring result because of
its highest phase-sensitivity to object height variations. However,
this traditional approach is not the optimal choice for suppressing
the impact of noise. To solve this problem, we analyze the statistics
such as biasedness and variance of noise-induced phase errors in a
general case about phase shifts. Using the phase error model, we
suggest a phase fusion strategy that calculates a linear combination
of all the available phase maps with different frequencies, instead of
discarding the low-frequency phase maps, to minimize the effects of
noise. The optimum weight for each phase map, which is related to the
fringe frequency and phase shifts, is deduced, and the minimized phase
error variance is derived. Simulation and experimental results
demonstrate the correctness of this principle and the effectiveness of
this method in improving measurement accuracies.
Evaluation of participants’ awareness of color vision deficiency: a comparative analysis of self-reported diagnosis and objective diagnostic testing
Authors: Jansone-Langina Zane , Truksa Renars
Published: January 2025

Despite the extensive literature on the challenges faced by people with color vision deficiency (CVD), significant gaps persist in participant awareness of the age of CVD diagnosis. This study aimed to investigate the extent to which participants are aware of CVD, focusing on their understanding of the deficiency. A total of 283 participants participated in a study designed to assess the age at which they became aware of their CVD, what color vision test their diagnosis was based on, and the challenges they faced. In addition, 190 participants underwent color vision testing using the Color Assessment and Diagnosis (CAD) test, compared to their knowledge of the type of CVD they have. The findings showed that 55% of the participants had found out about their CVD in adulthood, predominantly within occupational contexts. A substantial discrepancy was observed between self-reported diagnoses and clinical findings, with 43% of the participants being unable to specify their type of CVD. There is a necessity for enhanced early diagnostic practices, improved participant education about CVD, and increased public awareness to optimize the quality of life for affected individuals.
Performance enhancement in AlGaN deep ultraviolet light-emitting diodes with step doping n-AlGaN contact layer
Authors: Chen Qiushuang , Wei Yaju , Gao Jianghong , Gao Ge , Liu Hongyu , Lou Mingyue , Qi Shengli , Ye Jichun , Guo Wei
Published: January 2025

Optimizing the strain level within n-AlGaN contact layer is crucial for achieving high-efficiency deep ultraviolet light-emitting diodes (DUV-LEDs). In this study, a step doping strategy in n-AlGaN containing a lightly-doped bottom layer and a heavily-doped upper layer was proposed. The introduction of the lightly doped bottom layer mitigates issues such as strain accumulation and defect generation associated with heavily-doped n-AlGaN which traditionally impairs epitaxial quality and electrical performance of DUV-LEDs, even though similar dislocation density was identified between two LED samples. Thanks to the more uniform distribution of electron concentration and radiative recombination rate in the quantum well region, DUV-LEDs with step-doped layer exhibits 40% higher light output power compared with traditional structure. This work underscores the potential of doping engineering in advancing the performance of DUV-LEDs.
Data-based modeling of the light source color indicators on the Color Discrimination Index of the Forbidden City typical color paintings
Authors: Dang Rui , Wang Dongying , Wang Shuning , Tan Huijiao
Published: January 2025

The Forbidden City, one of the most magnificent palace architectural complexes in the world, has rich color details in the color paintings adorning the beams, plazas, and ceilings of its buildings, which hold high historical and cultural value. How to optimize the light source color indices to improve the color discrimination capability of the Forbidden City typical color paintings in a dim lighting environment is an urgent issue that needs to be addressed. In this study, based on the TM-30-20 standard, we set up 24 lighting conditions with different IES TM-30 fidelity index (Rf), IES TM-30 gamut index (Rg), IES TM-30 hue-angle bin local chroma shift values (Rcs,hj), and correlated color temperature (CCT). Forty-one observers standing at near and far observation distances conducted subjective evaluation experiments on the Color Discrimination Index of three typical Forbidden City architectural color painting samples. The results identified the light source color indices that significantly affect the Color Discrimination Index under different observation distances (near: Rg, Rcs,h7, Rcs,h12, Rcs,h15, CCT; far: Rcs,h12, CCT). The analysis of these indicators’ influence on the Color Discrimination Index of the Forbidden City typical color paintings led to the establishment of a corresponding mathematical model. Combined with defined evaluation levels for color discrimination capability, this provides a scientific basis for the evaluation and selection of light sources in the lighting design of the Forbidden City typical color paintings.
Robust multimode interference and conversion in topological unidirectional surface magnetoplasmons
Authors: Liu Chao , Zhao Ziyang , Guo Tianjing , Xu Jie , Deng Xiaohua , Yuan Kai , Tang Rongxin , Tsakmakidis Kosmas L. , Hong Lujun
Published: January 2025

We have theoretically investigated surface magnetoplasmons (SMPs) in an yttrium-iron-garnet (YIG) sandwiched waveguide. The dispersion demonstrated that this waveguide can support topological unidirectional SMPs. Based on unidirectional SMPs, magnetically controllable multimode interference (MMI) is verified in both symmetric and asymmetric waveguides. Due to the coupling between the modes along two YIG–air interfaces, the asymmetric waveguide supports a unidirectional even mode within a single-mode frequency range. Moreover, these modes are topologically protected when a disorder is introduced. Utilizing robust unidirectional SMP MMI (USMMI), tunable splitters have been achieved. It has been demonstrated that mode conversion between different modes can be realized. These results provide many degrees of freedom to manipulate topological waves.