bluuebunny/crossref_metadata_2025 huggingface dataset:
Trafficking of Migrants for Sexual and Labour Exploitation
Authors: Becucci Stefano
Published: October 2024

This chapter deals with the different forms of migrant trafficking in Southern European countries. It starts by pointing out the great discrepancy between estimates of trafficked people and official evidence, both worldwide and in the EU, with more specific reference to Spain, Italy and Greece. It follows an analysis of sexual-exploitation trafficking, considering the main changes that have occurred in each national sex market over the last three decades. It follows the recruitment, transportation and placement of victims into the new country, and the characteristics of the criminal organizations, both national and foreign, involved in this activity. The final part addresses the analysis of trafficking and the severe exploitation of migrants in the agriculture and textile sectors to highlight how the criminal dynamics and economic needs in Spain, Italy and Greece underlie labour exploitation.
Precarious Intimacies
Authors: MacNeil Taylor Faith
Published: October 2024

This book is about the reproduction of relationships amidst economic precarity. In it, the author focuses on the precarity that is generated by neoliberal rentier capitalism in Britain, homing in on the experiences of millennials living in both privately and socially rented accommodation in London. The book’s focus on millennials speaks to the intergenerational ruptures that have accompanied the advancement of neoliberalism in Britain in the 40 years preceding this book’s creation, whereby the nuclear homeowning family model is no longer as economically viable owing to the scarcity of affordable housing. Taking this phenomenon as its premise, albeit critically, this book explores the different ways that relational reproduction is imagined and practised by millennial Londoners living in both privately and socially rented accommodation, with a particular focus on the Borough of Hackney.
Precarious Intimacy
Authors: MacNeil Taylor Faith
Published: October 2024

This chapter provides a conceptual overview of the theoretical literature and research on precarity, intimacy and reproduction. It unites these concepts to formulate a theory of precarious intimacy as the ‘place between difficulty and desire’ in insecure rented accommodation. This chapter also offers a geo-historical account of the assetisation of housing in Britain and specifically in London, with emphasis on the imperialist politics undergirding this process.
Migration, Crisis and Temporality at the Zimbabwe-South Africa Border
Authors: Vanyoro Kudakwashe
Published: October 2024

This book is an empirical and theoretical enquiry into the constitution of Zimbabwean migrants at the Zimbabwe–South Africa border as political subjects. This focus is situated in a dynamic context of crisis where state and non-state perspectives on the situation in Zimbabwe have varied since Robert Mugabe’s demise from power. The enquiry necessitates taking an interest in the experiences of Zimbabwean migrant men crossing the border through irregular means who end up waiting in a transit shelter under the care of humanitarian and religious actors. This allows the book to make three arguments which contribute to wider theorising of migration governance and borders, challenging a) binary understandings of how power operates on the lives of Africa’s border dwellers, and b) the dominance of spatial perspectives in thinking about African borders. First, the making of the Zimbabwe–South Africa border and migration governance regime is not merely a territorial process but one situated in time and space. Second, we are seeing in the context at hand, as elsewhere, not merely direct regulation of mobility by the state but also through bureaucratisation of displacement in humanitarian institutions that have stepped into matters regarding the management and care of migrant lives. Third, the Zimbabwe–South Africa border is not as knowable as the common power–agency binary may suggest but a site of ambiguity that produces paradoxical effects for immobile migrants in different places and times. This temporal engagement takes us to a place of understanding that this paradox occurs through an intricate entanglement of practices of government and subversion, even if it is in ways that may not always allow the governed to shape and transform regimes of government.
The Neurodynamics of Technically Mediated Motion: Perceptual vs. Conceptual Animation in Artworks of Nam June Paik and Bill Viola
Authors: Hayles N. Katherine
Published: October 2024

Stillness has always been the dark other to animation’s motion, providing the foundation for motion when the frame rate reaches 24 fps. These well-known facts have recently been given an empirical foundation by neurological research into nonconscious cognition. A deeper understanding of how nonconscious process works together with conscious perception highlights the importance of recursive dynamics to animation’s effects and leads to a theoretical framework distinguishing between perceptual and recursive animation. This framework sheds light on the complex recursive dynamics that Nam June Paik explored through several of his artworks. Through the work of video artist Bill Viola, it also opens new ways to understand how stillness and motion may be seen as a continuum rather than a binary either/or perception. Together, these developments suggest that recursive dynamics constitute a relatively unexplored area within animation theory, providing a basis of rethinking the relation of theory and practice in artworks using stillness as well as motion to achieve their effects.
Moving Images and Human Perception: Affect in Hand-Drawn Animation and Computer-Generated Imagery
Authors: Tamari Tomoko
Published: October 2024

The paper discusses the human perception of animation by scrutinizing ‘the affective effect’ in the dynamic relations between moving images and human conscious–nonconscious cognition. While computer-generated imagery (CGI) refers to the process that involves mathematical calculations within computers to create verisimilar naturalistic images, the hand-drawn animation method involves symbolic expressive forms created by the animator’s spatiotemporal sensitivities. Drawing on Hayles’s discussion of the ‘cognitive nonconscious’, Simondon’s notion of ‘technical mentality’, and biosemiotics, the paper argues that there might be an inevitable incompatibility in the image formation process between human perception and algorithm-based CGI. To explore this assumption, the paper focuses on the questions of ‘selectivity’ and ‘abstraction’ in both the neuronal and the technical, and emphasizes the significance of ‘noise’ (incompleteness and ambiguity) and ‘time’ (speed, duration, and delay) for human perception by exploring the nature of cognitive systems. The paper further considers the expansion of digital computer technology and its integration within human life by analysing the ‘recursive dynamism’ of human perception and CGI, and argues that digital experience becomes a significant part of the constitution of human perception in a digital computational society.
On Pixar’s Marvellous Astonishment: When Synthetic Bodies Meet Photorealistic Worlds
Authors: Jenkins Eric S.
Published: October 2024

This chapter shows how the affective relation of character body and world has presented problems for Pixar specifically and computer animation generally, and how Pixar’s ‘feel’ stems from their unique solution. Pixar’s solution consistently constructs photorealistic worlds inhabited by synthetic characters. Pixar’s ‘feel’ is labelled marvellous astonishment, a phrase that indicates the combination of astonishing photorealism with marvellous animation. This relation can be found most directly in ‘impact images’, which are those filmic moments where the synthetic characters collide with or otherwise contact the photorealistic world, as illustrated through an analysis of Incredibles 2. The chapter concludes by illustrating how Pixar’s marvellous astonishment constitutes an ideological translation fit for control society.
Player and Avatar in Motion: Affective Encounters
Authors: Bruns Daniela
Published: October 2024

This chapter examines the complex interactions between player, game mechanics, hardware, and narrative, leading to affective experiences in video gaming. First it explores the relationship between human bodies and video game controls, emphasizes that players develop a deep understanding of the control interfaces, transforming them into an extension of their bodies. Then it discusses the interplay between players and avatars, focusing on embodiment, identification, and emotional investment, concluding that this relationship evolves throughout gameplay, oscillating between moments of affiliation and alienation. Finally it presents situations of machinic interludes without direct input from the player and finds that these moments nevertheless maintain the players’ bodily tension because the game’s environment is always charged with the promise to act.
The Isolation of the Island: The Social Impasse in Ischia after the Earthquake and Tourism Crises (2017–22)
Authors: Gugg Giovanni
Published: October 2024

Ischia is a volcanic island that became a popular tourist destination in the 20th century. However, this caused a sharp increase in anthropogenic pressure. No earthquakes were recorded for over 130 years, until in August 2017 an earthquake shook the municipality of Casamicciola, causing two deaths and thousands of displaced persons. Five years later, despite announcements by politicians, reconstruction has not begun, 1,400 people are still displaced, and at least 400 have changed residence. The institutional machine has had three ‘extraordinary commissioners’ and has produced many studies and plans, but many citizens have decided to reconstruct without the support of the government. The long delay in reconstruction has caused a general disillusionment, so that some believe that the ‘phantom reconstruction’ is like a ‘second death’. The crisis of the tourism sector since 2020 is added to this, due to the Covid-19 pandemic, the war in Ukraine (with the collapse of international tourism, especially from Russia) and a landslide that killed 12 people on 26 November 2022. The ‘latency time’ that always follows a disaster is further subjected to further slackening from a bureaucratic system that, to guarantee control and equity, not only generates uncertainty towards the future but also fragments local communities.
Local Communities as Strangers In-Between: The Paradigm of Aleatory Politics in Post-earthquake Central Italy (2016–17)
Authors: della Sala Francesco Danesi
Published: October 2024

This chapter deals with the political reflection of the 2016–17 Italian Apennine seismic disaster. Specifically, it focuses on disaster governance to ethnographically explore the contradictory and uncertain experiences that it may produce within a paradigm of deregulation, exception and legal undecidability. Post-disaster contexts often unveil the ordinary vulnerabilities and disparities that have historically afflicted local communities. Moreover, discourses and representations of the disaster shed light on the relations between decision-making centres and stricken areas. In our case, the earthquake and its political double have led to an ‘in-between’ condition of spectrality, which local inhabitants have elaborated as an intentional abandonment strategy by the national government. Thus, we analyse how deceptive expertise and total bureaucratization of the reconstruction process are inherently dependent both on top-down abstract representations of the space and the consequent production of idealized scenarios. Furthermore, we retrace the long-term unintended consequences produced by State-led interventions in three of the most severe Italian earthquakes of the last century, showing how the disconnected ‘aleatory’ politics of disaster governance constitutes a heterogeneous paradigm of socio-economic experimentations and failures.
When the Unexpected Becomes Frequent
Authors: Bertin Mattia
Published: October 2024

The impact of disasters usually has a national echo, with a sensationalization that attracts extraordinary funds and ad-hoc recovery policies. Much less spectacular, but potentially even more dangerous for local systems, are the increasingly frequent minor events. Far from being newsworthy, however, these events can in the long run become the main source of disaster. The direct damage caused by an event is only one part of their negative externalities. There are other important indirect damages caused by this multitude of frequent events. The sequence of these events could collapse the system in question much more than a single major event by acting on the breakdown of collective trust in the affected local system. Climate change also entails an increase of disaster risk related to the frequent repetition of minor events. This chapter describes the progress of landslide and high wind events effects in the Italian northeastern mountains before, during, and after the 2018 VaiaStorm. The paper will show how minor events precede and follow the known disaster, and prevent a real recovery, causing ancillary damages that in the long run negatethe possibility of local communities and territories recovering.
“He’s Never Even Had a Magnum!”
Authors: Herrity Kate
Published: October 2024

This chapter considers the challenges of rejoining life beyond the wall, and the time signature of life on the out. Using temporal vertigo as a starting point, this goes on to explore the jarring temporal dissonance of balancing awareness of both here and there and the challenges of leaving the prison behind for both prisoners and staff.
A Night Inside
Authors: Herrity Kate
Published: October 2024

This chapter discusses the way time and space distort and expand during the course of a night spent inside the prison. It explores the difficulty of navigating spaces rendered alien in the solitude of night patrol, and details an account of self-harm, considering the perils of keeping the count.
Emotional Contagion
Authors: Herrity Kate
Published: October 2024

This chapter considers what sound reveals about how the emotional climate is assessed and ‘feeling’ can spread around the prison. What does a ‘bubbly’ day sound like and what are the implications of this for how we understand when trouble is coming? Changes in the environment following the tobacco ban and implications for mamba use offer illustration.
Singing Frogs, Looping the Slam
Authors: Herrity Kate
Published: October 2024

This chapter considers the role of sound in processes of institutionalization, revisiting Goffman’s concept of ‘looping’ to explore how modified behaviours can indicate degree of immersion in the prison system and how these processes can be mitigated – or indicated – by shifting relationships.
Bells, Whistles, Ships and Prisons
Authors: Herrity Kate
Published: October 2024

The symbolic potency of the prison and how this manifests in the bells, whistles and ships of everyday life are considered here, before a broader picture of the problems and challenges facing Midtown and a creaking prison system. The relationship between Midtown and its broader community are reflected on, as well as the array of social problems threatening stability in the rip tide, both inside and out.
Shipping Out
Authors: Herrity Kate
Published: October 2024

The final chapter explores the complexities of ‘shipping out’ or leaving and accompanying rituals, both for those living and working in the prison, and the researcher. Goodbyes have an additional weight inside, where seeing someone again can indicate life has not gone well. How to say goodbye when so many songs remain unheard?
Extensions as Infrastructure: The Temporalities between Subjugation and Liberation in Jayapura, West Papua
Authors: Simone AbdouMaliq
Published: October 2024

This chapter engages Jayapura – West Papua’s largest urban region – as a site to explore how the infrastructural intersections of multiple temporalities give specific shape to the city. These temporalities emerge from a tense interplay of continuously revised modalities of domination and resistance, as well as registers that are more ambiguous. The chapter develops an account of ‘Papuan time’ that exposes tensions between contracting and protracting temporalities: between modern development narratives portraying indigenous Papuans as ‘frozen in time’, the lived experience of time as ‘broken’ with the loss of national self-determination, and the extension of differential infrastructures that attempt to reclaim time amid the uncertainty of an ‘interminable present’. It is argued that these vital processes and relations shaping Jayapura serve as an infrastructure for inhabitations that suspend clear trajectories of either subjugation or liberation. Urban ‘extensions’ constitute spatio-temporal infrastructures that lend support to Papuan configurations of temporality, of momentary experiences of freedom enabling at least affective rehearsals for a national liberation that is continuously deferred.
Desynchronized Infrastructures of Care: Suburban Imaginaries Re-Examined
Authors: Biglieri Samantha , Keil Roger
Published: October 2024

Abstract This chapter examines the temporalities of infrastructure at the intersection of health, disease, and urbanization through two cases focusing on care and wellbeing in seemingly unchanging suburbia. The first case assesses the experiences of peripheral immigrant communities in Brampton, Ontario, during the COVID-19 pandemic, detailing how swift real-time community action counteracted structural infrastructure deficiencies in healthcare and governmental pandemic response. The second case explores the ‘forever present’ everyday lives of people living with dementia in the suburbs of Greater Toronto. In thinking across these examples, the chapter demonstrates how the experience of suburban life has changed, both as the COVID-19 pandemic accelerated the need to respond to healthcare deficiencies, and as changing mobility infrastructures have tested the ability of people living with dementia to cope with shifting rhythms of daily life in their community. Utilizing the lens of infrastructural temporality, the chapter makes connections across Toronto’s ‘sick suburbs’ to (1) demonstrate the incompatibility of existing urban infrastructures with the needs of people who have fallen out of the ‘normal’ time frames for which those infrastructures were designed, while (2) indicating how quotidian agency can enable alternative temporalities and infrastructure futures to manifest.
‘Seeing for Real’: Forensic Pathologists Testing the Demonstrative Power of Postmortem Imaging
Authors: Schnegg Céline , Rey Séverine , Dominguez Alejandro
Published: October 2024

Modern postmortem imaging is increasingly being used to complement conventional autopsy. The integration of these radiological techniques into the forensic investigation process challenges the examination of the corpse and the cause of death investigations. During our long-term ethnography in a Swiss forensic medicine centre, we observed forensic pathologists’ and radiologists’ practices and their regular discussions about discrepancies between radiological interpretations and direct observations of bodies and organs. We argue that these two techniques enact two ‘realities’ of the body and its lesions that are not necessarily congruent. Thus, when radiology and scalpels do not tell the same truth, forensic pathologists work to test and reconcile these two ‘versions’ of the body: they make a distinction between the ‘real’ elements and the ‘artefactual’ ones, discussing the respective demonstrative power of radiological techniques and autopsy. We demonstrate that radiological images have a lower degree of reality within forensic expertise as they must be confirmed by the senses of the forensic pathologist during autopsy, which remains the ultimate visualization technique.
Rehabilitate or Euthanize? Biopolitics and Care in Seal Conservation
Authors: Hoerst Doortje
Published: October 2024

The common seal population in the Dutch Wadden Sea is at carrying capacity, meaning that the population is at its maximum considering currently available food resources. It follows that life and death blur together as the life of one seal might mean the death of another, albeit in different temporalities. While a seal centre was established to care for the common seal population through rehabilitation, ecologists argue that seal rehabilitation might be an act that can weaken, rather than strengthen, the population. Therefore, lungworm parasites as drivers of ‘natural selection’ processes for seals in the Wadden Sea would need to be respected. I argue that lungworm parasites resituate the biopolitical power of the seal rehabilitation centre. Through science and technology, the seal centre explores options of multispecies ‘collaboration’ with lungworms to decide which seal should be rehabilitated and which one should die through euthanasia. This collaboration has the potential to put lungworms in a leading biopolitical role, while the seal centre can assist in medically alleviating the seals’ pain throughout the process. While the seal centre tries to evade public questioning of decisions about life and death through the centring of facts and science, ethical implications and considerations remain complex.
Material Entanglements of the Corpse
Authors: Trabsky Marc , Flore Jacinthe
Published: October 2024

This chapter examines how the recycling of cadaveric tissue in the 21st century problematizes legal epistemologies of the corpse. The chapter begins by unpacking the development of legal doctrine on proprietary interests in the corpse since the 17th century. It then explores how doctrinal perspectives have increasingly become challenged by technologies that repurpose cadaveric flesh, skin and bone for a global market of medical devices, implants, treatments and pharmaceuticals. The technologies involved in recycling necro-waste in the creation of biomedical products invite an alternative perspective of knowing the corpse. They do so by revealing the human cadaver to be fragmented, relational and materially entangled. Drawing on the writings of feminist new materialism, the chapter rethinks epistemological conceptualizations of the corpse through discourses of waste and recycling. It calls for a rethinking of how the corpse is conceptualized in law, not in terms of whether it is a person or a thing, but through its intra-activity with matter, discourse and institutions.
Opening the Sweatbox: Purgatory and Debt Advice
Authors: Roche Zach
Published: October 2024

The time when the debtor ought to declare bankruptcy but does not do so has come to be called the sweatbox. In this chapter I unpack the experience of the sweatbox through the economic theology of purgatory. Purgatory is a timeless experience where those confined must submit to endless tests and trials to show penitence and reform. Time in the sweatbox has this character, with their willingness to pay in this period being used later during their insolvency application to show how apologetic they truly are. Eventually, however, their time in the purgatorial sweatbox comes to an end as they accept they need help. Using Foucault’s concept of pastoral power, this chapter covers how debtors choose which experts (or pastors) to listen to. Debt advisors emerge as the key pastor in question, as they give the debtor crucial information and the language they need to navigate their ongoing negotiations with their creditors. The chapter concludes with debtors investigating insolvency for the first time as they prepare to meet with a Personal Insolvency Practitioner.
Applying for Insolvency
Authors: Roche Zach
Published: October 2024

This chapter closely examines the meeting between the Personal Insolvency Practitioner and the debtor who wishes to be made insolvent. From a distance, this appears to be a bureaucratic meeting based on rules, but in reality it is a carefully negotiated series of micro-interactions that takes the form of a Foucauldian confession. The practitioner lacks the time or resources to fully investigate the financial case of each client. Instead, they bring the debtor to their office and ask them to explain everything that has happened in the form of a moral story, seeking to gauge how contrite and apologetic the debtor is. A strong element of class and gender emerges here, with working-class debtors attempting to placate the middle-class gaze of the practitioner, while women must choose to either adopt or resist the negative stereotypes associated with women in financial distress. This chapter unravels the implications this has for the governmentality of debt and debtors as they navigate this system and are increasingly pushed to embody entrepreneurial norms and become responsibilized subjects.
Facts and Narratives of the UK Drug Policy Context
Authors: Stevens Alex
Published: October 2024

This chapter provides the context for understanding recent developments in drug policy in the UK. It discusses patterns and trends in drug policy, in harms related to drug use, and in levels and types of illicit drug use in the UK. It shows the competing narratives for framing and explaining the observable facts of the case. This includes the long-standing dominance of policy actors concerned with public health and social control, known as the medico-penal framework. It shows the struggle to define drugs as either a problem of health or of crime. And it shows the remarkable stability of illicit drug use, despite narratives of dramatic increases, and decades of effort to eradicate this use.
Policy Constellation: A Critical Realist Approach
Authors: Stevens Alex
Published: October 2024

This chapter presents a new approach for explaining the outcomes of policy processes: the policy constellations approach. This is based on the assumptions of critical realism. It also draws from existing theories of the policy process, such as the advocacy coalition framework. Policy constellations are described as fluid sets of actors who gravitate towards each other on the basis of shared preferences and norms. Their ethico-political bases provide a ‘shared mission’ which brings them together but repels them from other actors, in different constellations, who have different ethico-political bases. In loosely concerted actions, they deploy the various forms of political and social power. The chapter also discusses the reflexivity of the policy constellations approach.
Moralities in Action: The Ethico-Political Bases of UK Drug Policy
Authors: Stevens Alex
Published: October 2024

The chapter describes and exemplifies the five main ethico-political bases observed in UK drug policy making. These are derived from abductive analysis of data on UK drug policy as informed by existing theories on moral intuitions. They show the foundations of drug policy in different forms of morality. These ethico-political bases are compassion, traditionalism, paternalism, progressive social justice and liberty. The compatibilities and oppositions between them are used to draw a modified circumplex of ethico-political bases. This helps explain the overlaps and gaps between policy constellations, based on underlying cultural structures of moral attraction and repulsion.
Learning Convivencia at School: Lessons on Peaceful Coexistence Policy Enactment from El Salvador
Authors: Martin Pauline
Published: October 2024

Policies and programmes on school convivencia (peaceful coexistence/positive school environment) have been broadly promoted in Latin America in recent decades, particularly in contexts of high levels of social violence, such as in El Salvador. In these settings, education is considered an essential instrument for strengthening peace and democracy. This chapter examines three unsuccessful attempts in El Salvador to achieve fundamental changes in interpersonal relationships in school convivencia. These attempts related to student participation in school governance, bullying, and sexual violence. Findings are derived from a comparative analysis of studies on each of these initiatives. An analytical framework centred on the interaction of ideas, actors, and institutions is used to examine the concept of convivencia, the role of actors at and across various levels of the education system, and the institutional strengths and weaknesses that affect the ability to formulate, implement, and evaluate these policies. The cross-case analysis demonstrates the complexity of addressing reforms focused on interpersonal relationships in schools that are, in turn, immersed in a broader cultural context. This chapter suggests the need to strengthen the role of multiple social actors, such as teachers, families, and local communities, in recognition of their power to enact or block a policy.
What Are Social Change Makers and Social Change Organisations?
Authors: Roth Silke , Saunders Clare
Published: October 2024

This chapter develops the core concepts of the book – social change makers (SCM) and social change organisations (SCO). The first part of the chapter focuses on the SCMs and explains that a biographical perspective is needed to understand their involvement in SCOs. The second part of the chapter reviews the ways in which SMOs, NGOs, and not-for-profit organisations have been conceptualised in the existing literature. The work stresses the overlapping functions and remits of organisations that are often pigeon holed leading to siloed knowledge of SCOs. The chapter makes the case for why SCOs is a better concept than previous conceptualisations of such organisations. Furthermore, a variety of SCOs are introduced and our argument is situated vis-à-vis existing scholarship. The third part of the chapter reviews different forms of SCM involvement in SCOs.
No Such Thing as a Free Gift: The Sources and Consequences of Resource Choices
Authors: Roth Silke , Saunders Clare
Published: October 2024

To carry out their work, SCOs need to mobilise a variety of resources. This chapter considers the different types of resources that SCOs require that are related to the tactics they perform and their organisational structures. Roth and Saunders illustrate how all resource choices have a cost-benefit balance, which – true to the interactionist approach that underpins the book – leads to further sets of actions and reactions among SCOs. The chapter demonstrates that every resourcing choice involves compromises and that none can ever be perfect. The first section of the chapter considers how resource demands are related to the strategies and tactics of SCOs. Organisations with different primary functions, goals and specialisms require different combinations of material and non-material resources. The second part discusses the sources from which SCOs obtain resources and how this relates to their goals and values. The third part focuses on the consequences of resource choices, including organisational pathways and technological change. How do organisations that seek upward accountability (towards donors) fare – are they more at risk of organisational demise? And do SCOs that side-step downward accountability (towards communities) risk distancing themselves from their constituencies (value accountability)?
Generation of frequency-shift keying (FSK) and amplitude-shift keying (ASK) RF signals by diode-tuned Fourier domain mode-locked opto-electronic oscillator
Authors: Hao Peng , Huang Yijing , Chen Guangyu , Dong Ziyi , Niu Jiaqi , Yao X. Steve
Published: October 2024

An approach to the generation of frequency-shift keying (FSK) and amplitude-shift keying (ASK) RF signals with a diode-tuned Fourier domain mode-locked opto-electronic oscillator (FDML OEO) is proposed and demonstrated. We use a low-cost varactor diode tuned phase shifter to form a high speed tunable bandpass filter (TBF) to implement the FDML-OEO. When a square wave modulation signal is used to drive the TBF, FSK RF signals are generated, with the flexibility to easily change the center frequency and tuning bandwidth of the FSK signals. For the ASK RF signal generation, a band-pass filter (BPF) with a bandwidth less than the TBF tuning range is added to the FDML OEO RF feedback loop. When the TBF center frequency hops in and out of the BPF bandwidth within a mode locking period, the FDML OEO generates ASK RF signals. The phase noises of the FSK and ASK RF signals generated by our FDML-OEO are both measured to be −123dBc/Hz at 10 kHz offset frequency. The key significance of this approach is that no microwave source is required to generate the ASK signal and reconfigurable FSK and signals, which may find wide applications in future radar and communications systems.
Introduction of a modified anomalous vortex beam with self-focusing properties
Authors: Al-Ahsab Hassan , Cheng Mingjian , Cao Yuancong , Zhang Huan , Yi Xiang , Yan Xu , Guo Lixin
Published: October 2024

This study introduces and experimentally demonstrates the concept of a modified anomalous vortex beam (MAVB), which carries orbital angular momentum (OAM) and exhibits unique self–focusing properties. By utilizing holographic techniques and customizing phase masks, we precisely control the beam’s phase and intensity distribution, enhancing self-focusing behavior while preserving traditional anomalous vortex beam features. We derive an analytical formula to describe MAVB propagation within a paraxial ABCD optical system. The self–focusing characteristics are influenced by initial parameters such as beam order, quantum number, beam waist, wavelength, and the modification parameter. Additionally, we simulate MAVB propagation and their OAM spectrum in maritime atmospheric turbulence. Through comprehensive theoretical analysis and experimental validation, we show how MAVBs achieve controlled self–focusing, leading to enhanced beam control and stability. Our study explores the mechanisms, design principles, and practical implications of MAVBs, emphasizing their potential to revolutionize optical applications.
Visible-light fiber Bragg grating-based wearable optical sensor
Authors: Peng Bo , Yue Xu , Song Enlai , Ran Yang
Published: October 2024

In this work, we proposed, for what we believe to be the first time, a wearable optical sensor based on the higher-order harmonic fiber Bragg grating (FBG), which has the advantages of easy fabrication, visible window operation and cross-talk removal. The fifth-order harmonic Bragg grating was inscribed by use of the conventional C-band phase masks and excimer laser but resonated in the visible spectrum. The visible window FBG can not only significantly improve the bandwidth of utilization, but also endow the sensor with visual perception. As was encapsulated by the PDMS pad, the wearable FBG held the temperature and bending sensitivity of 7.16 pm/°C and 4 pm/deg, respectively. Furthermore, taking advantage of the abundant resonances in harmonic FBG, a sensitivity matrix was established based on the orchestration of fifth and second-order harmonic resonances to discriminate the cross-sensitivity between temperature and bending. Our research provides new sight for the future development of wearable optical sensors.
Signal-to-noise ratio enhancement for digitalizing low amplitude wideband signals in photonic analog-to-digital converters
Authors: Qin Ruiheng , Zhou Defu , Chen Xinpei , Zhang Le , Wu Jiaxing , Zou Weiwen
Published: October 2024

Photonic analog-to-digital converters (PADCs) have been investigated for nearly five decades as a promising approach to overcome the bandwidth and jitter problem and bring ADC performance to new levels. However, low-amplitude signals often struggle to achieve full-scale quantization accuracy, posing a basic challenge for achieving high signal-to-noise ratio (SNR) digitization. Here, we established an optical carrier-to-sideband ratio (OCSR) based sampler model to achieve the optimal combination of the modulation, loss compensation, and photoelectric detection processes. The OCSR-based sampler features the advantages of high useful signal gain, low noise figure, and the ability to function over a very wide frequency range. The low-bias region is investigated, and the corresponding OCSR is selected as the transfer function for the Mach-Zehnder modulator (MZM). The OCSR-based sampler enables a higher gain of the radio frequency (RF) information signal sidebands. After the beating at the photodetector, the useful signal power reaches the digitizer's full scale to fully utilize the quantization accuracy, thereby enhancing the SNR of the whole system. In the experiment, a 20 GSa/s PADC with 4 interleaved sub-channels is configured out. Considerable advantages of the proposed OCSR-based sampler over conventional quadrature-biased sampler are demonstrated in comparative tests. A ∼5 dB enhancement in SNR and an increase of ∼0.8 effective number of bits (ENOB) are achieved under sinusoidal signals, and linear frequency modulation (LFM) signals with 8 GHz instantaneous bandwidth as well.
Suppression of Brillouin scattering-induced noise in long-haul high-power RoF links via non-uniformly distributed four-tone phase modulation
Authors: Chen Shengkun , Zhang Yaowen , Zou Xinhai , Tian Huan , Lyu Weiqiang , Xu Ying , Zhang Zhiyao , Li Heping , Liu Yong
Published: October 2024

An approach to suppressing Brillouin scattering-induced noise in long-haul high-power radio-over-fiber (RoF) links is proposed via non-uniformly distributed four-tone phase modulation. Four single-tone signals with uneven frequency intervals are utilized to phase modulate the optical signal before transmission. The power transferring from the optical carrier to the non-uniformly distributed modulation sidebands largely suppresses the Brillouin scattering-induced relative intensity noise (RIN). In the experiment, transmission of a 64-QAM wireless communication signal centered at 10 GHz and with a bandwidth of 100 MHz is demonstrated. The threshold of the stimulated Brillouin scattering (SBS) in a high-power RoF link involving a spool of a single-mode fiber (SMF) with a length of 20.5 km is increased by 11 dB based on this scheme, compared with that without phase modulation. Under an input optical power of 19 dBm, the error vector magnitude (EVM) and the adjacent channel leakage ratio (ACLR) are optimized from 34.39% to 1.32% and from −20.73 dBc to −35.32 dBc, without and with phase modulation, respectively. This scheme paves a way to realizing long-haul high-power RoF links for efficiently transmitting broadband wireless communication signals in cloud radio access networks (C-RANs).
Research on the aperture angle-matched collimated illumination method for the dark-state light leakage of LCD target simulators
Authors: Peng Yutian , Sun Gaofei , Zhang Jierui , Yang Jianhua , Xu Da , Meng Yao , Liu Shi
Published: October 2024

Aiming at the problem of overbrightness of the target simulator background for LED backlight panel illumination, a 5° aperture angle-matched collimated illumination method for the target simulator is proposed based on the study of the dark-state leakage of the LCD display device and the scattered stray light of the system. After simulation analysis the method can make the display contrast increase by 3.1 times and solve the problem of dark targets being drowned by the background bright light, which exists in the LED illumination target simulator. It is experimentally verified that the target simulator using the aperture angle-matched collimated illumination method shows a 2.8 times improvement in SNR and effectively reduces the energy of the dark-state background.
1.8 mJ pulses at 1560 nm based on a 55 µm core pure-erbium-doped VLMA fiber
Authors: Leconte B. , Leventoux Y. , Dauliat R. , Freysz V. , Vidal S. , Castaing M. , Février S. , Wondraczek K. , Jamier R. , Roy P.
Published: October 2024

Despite the increasing demand for high-energy erbium lasers for LIDAR imaging applications, the scaling of the current Er-Yb co-doped technology is still hindered by a 1 µm parasitic emission. In this study, we present the first, to the best of our knowledge, utilization of the REPUSIL powder synthesis method to fabricate a 55 µm double-clad fiber with a remarkably large modal area. Doped solely with erbium and free of ytterbium, its estimated cladding absorption is 2 dB/m at 976 nm, enabling short amplification lengths. We demonstrate its potential through direct amplification of a GHz femtosecond laser (M2 = 1.12) and notably, the generation of 1.8 mJ, 37 ns Q-switched pulses in oscillator configuration (M2 = 1.46).
Realization of robust high-Q resonances of BICsvia eigenfield perturbations in a multiple-notched nanocube metasurface
Authors: Huang Lei , Ding Chuanqi , Ren Jiduo , Sun Siyi , Wang Weiqing , Lai Wen-Yong
Published: October 2024

Non-radiative bound states in the continuum (BICs) allow the construction of resonances with high-quality (Q) factors and have emerged as an attractive platform for manipulating light–matter interactions on the nanoscale. However, current studies on symmetry-protected BICs (SP-BICs) suffer from a fundamental trade-off between the Q factor and asymmetric parameters, presenting a significant hurdle for practical applications. Here, utilizing the eigenfield perturbations, we successfully break the conventional inverse quadratic law of the SP-BICs and realize the robust high-Q resonances against the asymmetric parameters. We find the introductions of the central notch can efficiently boost the resonance of the electric quadrupole, which results in the enhancement of multiple-mode interference, and thus improving Q factors, while the constant effective refractive index guarantees the resonance with a stable wavelength. Our findings provide a promising strategy for modulating the light–matter interaction and may pave the way for applications in future high-performance optoelectronic devices.
Acoustic vortex-based dynamic lens for light focusing and steering
Authors: Hu Chia-Wen , Hsieh Zong-Han , Huang Chung-Han , Li Meng-Lin , Yeh Chih-Kuang
Published: October 2024

This study explores a technique for light manipulation using an acoustic vortex generated by a high-intensity focused ultrasound transducer. The acoustic vortex forms a ring of bubble wall near the high-pressure region, creating a lens-like structure that can effectively focus a laser beam. The effects of varying acoustic pressures and dissolved oxygen content on the focused ultrasound and vortex waveforms were tested. Results showed that the vortex waveform could enhance the laser beam peak intensity by 55.6% and reduce its full width at half maximum from 1.16 mm to 0.91 mm. Additionally, the study demonstrated the capability to dynamically steer the laser beam at angles ranging from 0° to 0.7°, achieving precise control without the need for mechanical components. This technique offers a stable, real-time, and on-demand method for light manipulation, with potential applications in various liquid environments and heterogeneous media. The study also highlights current hardware limitations and suggests future improvements for optimizing parameters and further exploring related mechanisms.
Speckle-decoded temperature-insensitive strain identification in a multimode optical fiber
Authors: Sun Hanchao , Wu Jixuan , Song Binbin , Wang Jifang , Liu Xiao
Published: October 2024

Fiber-optic sensing systems are significant tools for measuring various physical or biochemical parameters. However, temperature cross-sensitivity prevents accurate recognition of the target input signal when optical sensors are applied in practical scenarios. Herein, leveraging a deep learning algorithm, a speckle-decoded temperature-insensitive strain sensor is proposed and experimentally demonstrated. Scattering patterns are utilized to estimate the axial strain since the external force could change the coherent superposition of the amplitudes of propagating modes. The experimental results show that the recognition accuracy of the sensing system based on a classification model can reach 99.28% within a wide strain range of 0–0.3 N in the presence of temperature cross talk. In addition, the strain prediction demonstrates an average root-mean-square error of 1.02 N%. Such an intelligent speckle sensing strategy has the potential to broaden the applications of fiber-optic sensors in various engineering applications.
The expectations humans have of a pleasurable sensation asymmetrically shape neuronal responses and subjective experiences to hot sauce
Authors: Luo Yi , Lohrenz Terry , Lumpkin Ellen A. , Montague P. Read , Kishida Kenneth T.
Published: October 2024

Expectations shape our perception, profoundly influencing how we interpret the world. Positive expectations about sensory stimuli can alleviate distress and reduce pain (e.g., placebo effect), while negative expectations may heighten anxiety and exacerbate pain (e.g., nocebo effect). To investigate the impact of the (an)hedonic aspect of expectations on subjective experiences, we measured neurobehavioral responses to the taste of hot sauce among participants with heterogeneous taste preferences. By identifying participants who “liked” versus those who strongly “disliked” spicy flavors and by providing contextual cues about the spiciness of the sauce to be tasted, we dissociated the effects of positive and negative expectations from sensory stimuli (i.e., visual and gustatory stimuli), which were the same across all participants. Our results indicate that positive expectations lead to modulations in the intensity of subjective experience. These modulations were accompanied by increased activity in brain regions previously linked to information integration and the placebo effect, including the anterior insula, dorsolateral prefrontal cortex, and dorsal anterior cingulate cortex, as well as a predefined “pleasure signature.” In contrast, negative expectations decreased hedonic experience and increased neural activity in the previously validated “Neurological Pain Signature” network. These findings demonstrate that hedonic aspects of one’s expectations asymmetrically shape how the brain processes sensory input and associated behavioral reports of one’s subjective experiences of intensity, pleasure, and pain. Our results suggest a dissociable impact of hedonic information: positive expectations facilitate higher-level information integration and reward processing, while negative expectations prime lower-level nociceptive and affective processes. This study demonstrates the powerful role of hedonic expectations in shaping subjective reality and suggests potential avenues for consumer and therapeutic interventions targeting expectation-driven neural processes.
Assessing attitudes toward LGB people in young adolescents
Authors: Stiekema Elise , Warrens Matthijs J. , van Bergen Diana D. , Parlevliet Sanne
Published: October 2024

Since people’s attitude toward lesbians, gay men and bisexual people (LGB) affects young LGB people’s mental health and subsequently their quality of life, it is important to establish people’s attitudes toward LGB people. The current study examined attitudes toward lesbian, gay and bisexual people among Dutch students and the psychometrical characteristics of adapted instruments measuring attitudes toward sexual diversity. The students in the sample (N = 1.633) were recruited from secondary schools. The participants completed questionnaires with scales measuring attitudes toward LGB people. The results indicate that participants hold positive attitudes overall, but there are differences with regard to gender and educational level. In addition, the used instruments prove to be psychometrically sound for measuring LGB attitudes and this work contributes to the empirical debate about whether adolescents’ attitudes toward lesbians, gay men and bisexual people underly domains of a general attitude toward LGB people. Our results indicate that students do not seem to distinguish among sexually diverse subgroups much, possibly a sign of increased awareness and knowledge of LGB groups. The use of one general measure of attitudes of sexually diverse people may be considered in future research.