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Microsurgery is a particularly impactful yet challenging form of surgery. Robot assisted microsurgery has the potential to improve surgical dexterity and enable precise operation on such small scales in ways not previously possible. Intraocular microsurgery is a particularly challenging domain in part due to the lack of dexterity that is achievable with rigid instruments inserted through the eye. In this work, we present a new design for a millimeter-scale, dexterous wrist intended for microsurgery applications. The wrist is created via a state-of-the-art two-photon-polymerization (2PP) microfabrication technique, enabling the wrist to be constructed of flexible material with complex internal geometries and critical features at the micron-scale. The wrist features a square cross section with side length of 1.25 mm and total length of 3.75 mm. The wrist has three tendons routed down its length which, when actuated by small-scale linear actuators, enable bending in any plane. We present an integrated gripper actuated by a fourth tendon routed down the center of the robot. We evaluate the wrist and gripper by characterizing its bend-angle. We achieve more than 90 degrees bending in both axes. We demonstrate out of plane bending as well as the robot's ability to grip while actuated. Our integrated gripper/tendon-driven continuum robot design and meso-scale assembly techniques have the potential to enable small-scale wrists with more dexterity than has been previously demonstrated. Such a wrist could improve surgeon capabilities during teleoperation with the potential to improve patient outcomes in a variety of surgical applications, including intraocular surgery., Comment: 2 pages, 3 figures, published in the proceedings of the 2023 Hamlyn Symposium on Medical Robotics (HSMR) conference

Data and code for the article: Cutler, J., Wittmann, M.K., Abdurahman, A., Hargitai, L.D, Drew, D., Husain, M. & Lockwood, P.L. Ageing is associated with disrupted reinforcement learning whilst learning to help others is preserved. Nat Commun 12, 4440 (2021). https://doi.org/10.1038/s41467-021-24576-w

All data and analysis materials to reproduce results from "Ageing increases prosocial motivation for effort" (accepted in Psychological Science). Files 'K_values_2k1b', 'lme_data_PM_young_old_final' and 'PM_debrief_final' contain all the raw data. File 'analysis_code_PM_ageing_OSF' contains R code with comments for running statistical tests reported in the manuscript and 'Reproduce_figures_prosocial_ageing' contains R code for plotting the figures in the manuscript. Please contact Patricia Lockwood (patricia.l.lockwood@gmail.com) and Anthony Gabay (GabayAS@adf.bham.ac.uk) for any questions.

Decentralized control in multi-robot systems is dependent on accurate and reliable communication between agents. Important communication factors, such as latency and packet delivery ratio, are strong functions of the number of agents in the network. Findings from studies of mobile and high node-count radio-frequency (RF) mesh networks have only been transferred to the domain of multi-robot systems to a limited extent, and typical multi-agent robotic simulators often depend on simple propagation models that do not reflect the behavior of realistic RF networks. In this paper, we present a new open source swarm robotics simulator, BotNet, with an embedded standards-compliant time-synchronized channel hopping (6TiSCH) RF mesh network simulator. Using this simulator we show how more accurate communications models can limit even simple multi-robot control tasks such as flocking and formation control, with agent counts ranging from 10 up to 2500 agents. The experimental results are used to motivate changes to the inter-robot communication propagation models and other networking components currently used in practice in order to bridge the sim-to-real gap., 9 pages, 8 figures

At once omnipresent and undertheorized, genre is what nobody really believes in but everyone tacitly relies upon, whether they are writing literary criticism or consulting a pull-down menu on Netfl...

Social cohesion relies on prosociality in increasingly aging populations. Helping other people requires effort, yet how willing people are to exert effort to benefit themselves and others, and whether such behaviors shift across the life span, is poorly understood. Using computational modeling, we tested the willingness of 95 younger adults (18-36 years old) and 92 older adults (55-84 years old) to put physical effort into self- and other-benefiting acts. Participants chose whether to work and exert force (30%-70% of maximum grip strength) for rewards (2-10 credits) accrued for themselves or, prosocially, for another. Younger adults were somewhat selfish, choosing to work more at higher effort levels for themselves, and exerted less force in prosocial work. Strikingly, compared with younger adults, older people were more willing to put in effort for others and exerted equal force for themselves and others. Increased prosociality in older people has important implications for human behavior and societal structure.

In this study, we use a k-mean clustering approach to investigate the weather patterns responsible for extreme wind speed events throughout Mexico using 40 years of the ERA-5 atmospheric reanalysis. Generally, we find a large geographical split between the weather patterns that generate the strongest winds across the country. The highest wind power production periods therefore occur at different times in different regions across the country. In the South, these are associated with cold surge events, where an anticyclone is present in the Gulf of Mexico resulting in a strong Northerly flow across the Isthmus of Tehuantepec. In the North-East, Easterly trade winds are responsible for the strongest wind events, whereas in the North-West, it is the proximity of the North Pacific High. However, the weakest winds and lowest power production periods occur at the same times for all stations with the exception of Baja California Sur, meaning that low wind power production may be unavoidable at these times. The El Niño Southern Oscillation is found to influence wind speeds at some locations across Mexico at sub-seasonal time-scales. We report that statistically stronger wind speeds are observed during the Summer during El Niño months than during La Niña months for both sites in Chiapas and Oaxaca.

Supplemental material, sj-docx-1-pss-10.1177_0956797620975781 for Aging Increases Prosocial Motivation for Effort by Patricia L. Lockwood, Ayat Abdurahman, Anthony S. Gabay, Daniel Drew, Marin Tamm, Masud Husain and Matthew A. J. Apps in Psychological Science

Supplemental material, sj-docx-1-pss-10.1177_0956797620975781 for Aging Increases Prosocial Motivation for Effort by Patricia L. Lockwood, Ayat Abdurahman, Anthony S. Gabay, Daniel Drew, Marin Tamm, Masud Husain and Matthew A. J. Apps in Psychological Science

A rapid decarbonisation of power systems is underway in order to limit greenhouse gas emissions and meet carbon reduction targets. Renewable energy is a key ingredient to meet these targets, however, it is important that national power systems still maintain energy security with increasing levels of renewable penetration. The operating potential of renewable generation at times of peak demand (a critical time for power system stress) is not well understood. This study therefore uses a multi-decadal dataset of national demand, wind power and solar power generation to identify the meteorological conditions when peak demand occurs, and the contribution of renewables during these events. \ud \ud Wintertime European peak power demand events are associated with high atmospheric pressure over Russia and Scandinavia and are accompanied by lower than average air temperatures and average wind speeds across Europe. When considering power demand extremes net of renewable power production, the associated meteorological conditions are shown to change. There is considerable spatial variability in the dates of national peak demand events, and amount of renewable generation present. Growth in renewable generation has the potential to reduce peak demands. However these impacts are also not uniform with much larger reductions in peak demand seen in Spain than in central Europe. The re-analysis derived energy models have allowed for recent peak demand events to be put into a longer-term context.

Global growth in variable renewable generation has brought significant attention to the challenge of balancing electricity supply and demand. However, inter-annual variability of energy resources has only recently begun to feature in energy system assessments and receives limited recognition in policy discussion, let alone policy design. Meteorological reanalysis datasets that blend modern modelling techniques with historic weather records are seeing increased application in energy system studies. This practice offers insights for market and policy design implications as governments seek to manage the changing energy landscape, as seen with the UK’s introduction of the Electricity Market Reform policy package. Here we apply a concise, Load Duration Curve based approach to consider the market and policy implications of increasing variability in the Great Britain (GB) energy system. Our findings emphasise the growing inter-annual variability in operating opportunity for residual mid-merit and even baseload generation, alongside implications for capacity assurance approaches. The growth in wind generation is seen to bring an accompanying opportunity for increased solar generation, with its lower inter-annual variability and largely uncorrelated annual characteristic. The results underscore the need for an increased recognition of inter-annual variability when addressing market design and incentive mechanisms.

Rapid expansion of wind and solar capacity in Great Britain presents challenges for managing electricity systems. One concern is the reduction in system inertia during periods where renewables provide a high proportion of demand which has led to some networks imposing system nonsynchronous penetration limits. However, given the lack of operational data, the relationship between\ud renewable generation and demand for the full range of meteorological conditions experienced in Great\ud Britain is poorly understood. This study uses reanalysis datasets to determine the proportion of\ud demand from renewable generation on an hourly resolution for a 36-year period.\ud The days with highest penetration of renewables tend to be sunny, windy weekend days between May\ud and September, when there is a significant contribution of both wind and solar generation and demand\ud is suppressed due to human behaviour. Based on the current distribution of wind and solar capacity,\ud there is very little curtailment for all system non-synchronous penetration limits considered. However,\ud as installed capacity of renewables grows the volume of generation curtailed also increases with a\ud disproportionate volume occurring at weekends. The total volume of curtailment is highly dependent\ud on ratio of wind and solar capacity, with the current blend close to the optimum level.

Building upon the queer phenomenology of Sarah Ahmed and recent work in sound studies, this chapter examines two related practices (field recording and the transcription of field recording) to argue for a general position: sound, as such, is queer. The author transcribes two field recordings, rendering their immanent flow of recorded sound and speech into written form, and comments upon moments of inadequate transcription that are said to demonstrate the queerness of sound. Focusing on moments in which an object or event fails to generate a legible sonic trace, the resistance of sound to transcription functions as a test case for the theoretical assertion, widely held at present in queer theory, that queerness denotes the nonnormative.

Apathy is a common and under-recognized disorder that often emerges in the prodromal phase of Parkinsonian diseases. The mechanism by which this occurs is not known, but recent evidence from patients with established Parkinson’s disease suggests that serotonergic dysfunction may play a role. The integrity of the raphe serotonergic system can be assessed alongside dopaminergic basal ganglia imaging using the radioligand 123I-ioflupane, which binds both serotonin and dopamine transporters. To investigate the relative roles of these neurotransmitters in prodromal parkinsonism, we imaged patients with idiopathic rapid eye movement sleep behaviour disorder, the majority of whom will develop a parkinsonian disorder in future. Forty-three patients underwent brain imaging with 123I-ioflupane single photon emission computed tomography and structural MRI. Apathy was quantified using the Lille Apathy Rating Scale. Other clinical parkinsonian features were assessed using standard measures. A negative correlation was observed between apathy severity and serotonergic 123I-ioflupane signal in the dorsal raphe nucleus (r = −0.55, P < 0.001). There was no significant correlation between apathy severity and basal ganglia dopaminergic signal, nor between dorsal raphe signal and other neuropsychiatric scores. This specific association between apathy and raphe 123I-ioflupane signal suggests that the serotonergic system might represent a target for the treatment of apathy.

BACKGROUND: Apathy is an important neuropsychiatric feature of Parkinson's disease (PD), which often emerges before the onset of motor symptoms. Patients with rapid eye movement sleep behaviour disorder (RBD) have a high probability of developing Parkinson's disease in future. Neuropsychiatric problems are common in RBD, but apathy has not previously been detailed in this key prodromal population.METHODS: 88 patients with polysomnographically proven RBD, 65 patients with PD and 33 controls were assessed for apathy using the Lille Apathy Rating Scale (LARS). Cognition and depression were also quantified. The sensitivity of the Unified Parkinson's Disease Rating Scale screening questions for apathy and depression was calculated.RESULTS: 46% of Patients with RBD were apathetic, compared with 31% of Parkinson's patients in our sample. Most RBD patients with depression were apathetic but more than half of apathetic patients were not depressed. The sensitivity of the single UPDRS screening question was only 33% for mild apathy and 50% for severe apathy.CONCLUSIONS: Apathy is common in RBD and is underestimated by a single self-report question. Recognition of apathy as a distinct neuropsychiatric feature in RBD could aid targeted treatment interventions and might contribute to understanding of prodromal Parkinson's disease. This article is protected by copyright. All rights reserved.

Pratique embarrassante du journalisme en ligne, contestable dans la forme comme dans le fond, les listicles (neologisme obtenu par la contraction des mots liste et article) sont le douloureux quotidien de l’amateur de musique du troisieme millenaire. Attrape-clics, auto-promo, raccourcis problematiques… Ils condensent a eux seuls a peu pres toutes les tares de la presse en ligne dediee a la musique. En septembre 2014, dans les pages de The Quietus, Drew Daniel, moitie du duo electronique Matmos, professeur de litterature americaine et musicophage insatiable, retournait l’exercice, l’eventrait et en extirpait toutes les humeurs, pour mieux en exposer la profonde perversion.

This chapter interweaves Jasbir Puar’s foundational work on “homonationalism” and “terrorist assemblages” with discussions about Samson Agonistes and the War on Terror. Combining this with early modernist work on effeminacy, Daniel argues that a resemblance between Samson as an emasculated male and Dagon as a monstrous hybrid or “queer assemblage” provokes Samson’s razing of the Philistine temple. In this analysis, Samson’s final act of religious violence is an act of anxious displacement. Anxiety likewise explains critics’ painstaking efforts to distance Milton from Samson’s terrorist act. From this shared logic of displacement, we can perceive Daniel’s urgent call for a queer Milton criticism attentive to the manifestations and effects of anxiety, including its transformation into terror.

Enabling a future full of insect-scale robots will require progress on a huge number of fronts, one of which is the development of mobility platforms designed to operate beyond the scaling frontier of commercially available solutions. The vast majority of researchers seeking to create functional centimeter-scale flying robots have turned towards biomimetic propulsion mechanisms, specifically flapping wings. In this work I take a very different tack, investigating a propulsion mechanism with no natural analogue --- electrohydrodynamic thrust. Electrohydrodynamics (EHD), specifically in the context of corona discharge based systems, has been a long studied and, until relatively recently, often poorly understood phenomenon. The beginning of this dissertation focuses on the theoretical underpinnings of the thrust mechanism. The bulk of my work has focused on developing proof of concept demonstrators for EHD at the meso-scale. Starting with rapidly prototyped materials and quickly moving to microfabricated electrodes, a series of prototypes elucidate the potential for EHD to yield high thrust-to-weight ratio fliers. Initial demonstrations have been backed up by more rigorous investigations of electrode geometric and density effects. Quadrotor systems begin to suffer from decreased performance at and below the centimeter scale, especially with regards to increasing demands on durability of rotory components (which may not exist at scale), efficiency of available DC motors, and propeller figures of merit. Simply replacing the rotors with EHD thrusters, however, allows us to sidestep some of the unfavorable scaling laws of propeller-based propulsion while maintaining the ability to transfer domain knowledge from the rich world of quadcopter design and control. Demonstrating repeatable takeoff and rudimentary (open-loop) attitude control is trivial with external power supplied to the simple quad-thruster design. Through a combination of design and methodology (e.g., with regards to assembly) improvements, functional EHD-based ``ionocraft'' can now be built in about half an hour, with near 100% success rate. Controlled flight is now within reach. Merely hovering with tethered power and an off-board controller is only the beginning. The final sections of this work outline a variety of paths forward, towards better performance of a meso-scale ionocraft, autonomous operation, and further miniaturization. Ultimately, I believe the future is bright for ionocraft. While electrohydrodynamics may not be the most power efficient mechanism, nor the easiest to grasp conceptually, it is certainly the simplest to design; put two asymmetric electrodes close to eachother, apply a high voltage, and away it goes! In the words of a respected professor, how hard could it be?

We present a regime-switching vector-autoregressive method for very-short-term wind speed forecasting at multiple locations with regimes based on large-scale meteorological phenomena. Statistical methods short-term wind forecasting out-perform numerical weather prediction for forecast horizons up to a few hours, and the spatio-temporal interdependency between geographically dispersed locations may be exploited to improve forecast skill. Here we show that conditioning spatio-temporal interdependency on `atmospheric modes' can further improve forecast performance. The modes are defined from the atmospheric classification of wind and pressure fields at the surface level, and the geopotential height field at the 500hPa level. The data fields are extracted from the MERRA-2 reanalysis dataset with an hourly temporal resolution over the UK, atmospheric patterns are classified using self-organising maps and then clustered to optimise forecast performance. In a case study based on 6 years of measurements from 23 weather stations in the UK, a set of three atmospheric modes are found to be optimal for forecast performance. The skill in the one- to six-hour-ahead forecasts is improved at all sites compared to persistence and competitive benchmarks. Across the 23 test sites, one-hour-ahead root mean squared error is reduced by between 0.3% and 4.1% compared to the best performing benchmark, and by and average of 1.6% over all sites; the six-hour-ahead accuracy is improved by an average of 3.1%.

This essay focuses upon a single dramatic scene in order to address a general problem: what is the relationship between theoretical abstraction and emotional display? William Shakespeare and Thomas Middleton's collaborative play Timon of Athens seemingly insists upon the isometric correlation between affective service and the capacity to pay. Against this backdrop, there stands the ethical counterexample of Flavius, the “one good man” who, with tears in his eyes, remains loyal to his destitute master. Flavius’ affect prompts Timon to deploy a peculiar and symptomatic form: the logical syllogism. In what sense do Timon's syllogisms constitute a response to Flavius’ tears? In pursuit of answers to this question, this essay contextualizes the ambient tension between rhetoric and logic within early modern England, and considers the intersection of this dramatic scene with Hegel's account of the dynamic interdependence of lord and bondsman, and with Hegel's account of the relationship between logic and sexual ...

If the stoic tradition valorized self-killing as the ultimate example of the rational control of the passions, Christian thought regarded self-killing as a sin and a crime. Yet there is a third level at which medieval and early modern persons understood such actions as neither a moral quandary nor a philosophical exemplum but a medical problem for the emerging Renaissance sciences of life, vitality, and matter. What role might “affect” have in the understanding of self-killing as both an object of thought and a completed action when the explanatory force of humoral theory began to wane? This chapter examines two exemplary early modern texts that reveal the categorical problems and conceptual challenges posed by self-killing to emergent materialist accounts of the passions.

For early modern Christian subjects, Christ’s crucifixion and death fixes at the heart of things a momentary submission to decreation and destruction, replenished by the Resurrection and the promise of the Second Coming, but present all the same as a kind of absolute eclipse in ontotheology. With reference to the reworked “Nicene Creed” that closes Jane Bennett’s Vibrant Matter , this essay asks: what happens to political ecologies of vibrant matter when they confront the corpse of God? How might Renaissance political ecologies speak to contemporary political dynamics, and what stands to occupy the vacant place of suicide, then and now, within this communal nexus? This essay pursues answers to these questions by placing an early modern text on suicide, John Donne’s Biathanatos , into conversation with a contemporary theorization of community—Roberto Esposito’s Communitas: The Origin and Destiny of Community . Donne’s scandalous, even blasphemous, presentation of Christ as a “self-killer” in Biathanatos raises the possibility that Christian community is founded in the shadow of an originary yet occulted moment of self-destructive will, at once inferred yet unrepresentable. The socially binding consequences of this sacrificial dynamic are further explored in relation to contemporary politics, with reference to the focalizing effect of the suicide of Mohammed Bouazizi, the Tunisian street vendor whose self-immolation catalyzed the “Arab Spring” of widespread popular revolt.

This essay reads Antonio's mysterious sadness psychoanalytically but bypasses overfamiliar, and potentially reductive, translations of early modern melancholy into Freudian melancholia. Instead, Antonio's sacrificial longing to enter into the contract with Shylock and surrender the pound of flesh on behalf of Bassanio is read as a form of masochistic fantasy (via Deleuze, Silverman, Krafft-Ebbing, and Torok). The structure of subjection and desire at work within Antonio's melancholy and his masochism bears a wider family resemblance to the buried contradictions that drive the turning worlds of Venice and Belmont. The extraction of the pound of flesh is not Antonio's masochistic fantasy alone, but the political and ethical fantasy of subjection at the heart of the playtext that surrounds him. Articulating fault lines between Christian and Jew, master and bondsman, Venice and Belmont, letter and spirit, Antonio's simultaneously melancholic and masochistic cry—"Let me have judgment, and the Jew his will"—breaks open the economic and political conflicts at the core of The Merchant of Venice .

QUEER THEORY'S ANTI-ANTI RELATIONAL TURN Drew Daniel Jose Esteban Munozs new book fights for the future of a field— queer theory—arguably defined by the differences between two works from its recent past: Mu noz's own Disidentif cations: Queers of Color and the Performance of Pol itics (1999) and Lee Edelman's No Future: Queer Theory and the Death Drive (2004).' Insofar as Cruising Utopia marries an argument of crankily counterintuitive original ity to whipsmart readings of both familiar and underground queer artworks, it more than succeeds in living up to the high standard set by his previous book. Just as Dis identifications broke with then-pre vailing critical orthodoxies of gay affirmation and belonging in its evocation of the anti-identitarian

Lingering controversy about anti-Semitism has kept The Merchant of Venice off the screen. Michael Radford's 2004 film adaptation creates a critique of anti-Semitic violence revealingly at odds with the play's comic form. This review considers the challenge Shakespeare's art poses to the ethical imperatives of contemporary filmmaking.

Early modern studies has recently witnessed a striking resurgence of interest in Lucretius as a crucial figure for the dissemination of Epicurean atomism into the cultural bloodstream. Alison Brown, Catherine Wilson, Jonathan Goldberg, Stephen Greenblatt, and Gerard Passannante have all contributed distinctive book-length studies that track this process and theorize Lucretian after effects, echoes and resonances in the theology, history, painting, and poetry of the period.2 If there was ever a candidate for a “return of theory within early modernity,” then the return of the theory of atoms and void from medieval desuetude into the shocked, tantalized awareness of a particularly crucial galaxy of early modern readers from Machiavelli to Montaigne to Spenser offers a case in point of the uncannily necromantic return of dead ideas to virulent, conta- gious new life.