Surgical conditions in experimental laparoscopy: effects of pressure, neuromuscular blockade, and pre-stretching on workspace volume.

BACKGROUND: Establishing a pneumoperitoneum for laparoscopy is common surgical practice, with the goal to create an optimal surgical workspace within the abdominal cavity while minimizing insufflation pressure. Individualized strategies, based on neuromuscular blockade (NMB), pre-stretching routines, and personalized intra-abdominal pressure (IAP) to enhance surgical conditions are strategies to improve surgical workspace. However, the specific impact of each factor remains uncertain. This study explores the effects and side-effects of modifying intra-abdominal volume (IAV) through moderate and complete NMB in a porcine laparoscopy model. METHODS: Thirty female Landrace pigs were randomly assigned to groups with complete NMB, regular NMB and a control group. Varying IAP levels were applied, and IAV was measured using CT scans. The study evaluated the maximum attainable IAV (Vmax), the pressure at which the cavity opens (p0), and the ease of expansion (λexp). Cardiorespiratory parameters, including peak inspiratory pressure (PIP), mean arterial pressure (MAP), heart rate (HR), and cardiac output (CO), were continuously recorded to evaluate side-effects. RESULTS: There were no significant weight differences between NMB groups (median 21.1 kg). Observed volumes ranged from 0 to 4.7 L, with a mean Vmax of 3.82 L, mean p0 of 1.23 mmHg, and mean λexp of 0.13 hPa-1. NMB depth did not significantly affect these parameters. HR was significantly increased in the complete NMB group, while PIP, MAP, and CO remained unaffected. Repeated insufflation positively impacted Vmax; ease of opening; and expanding the cavity. CONCLUSION: In this porcine model, the depth of NMB does not alter abdominal mechanics or increase the surgical workspace. Cardiorespiratory changes are more related to insufflation pressure and frequency rather than NMB depth. Future studies should compensate for the positive effect of repeated insufflation on abdominal mechanics and surgical conditions.

Workspace Layout for Resilient Performance using Social Network Analysis: A Case Study.

Purpose: To present the social network analysis-based approach used to create a new workspace layout for three hospital services as part of a campus expansion at a large tertiary care public hospital. Objective: To analyze the relationships among service members across four healthcare resilience abilities (monitor, anticipate, respond, and learn) and utilize network metrics to indicate the suitability of a shared workspace layout for the services. Background: The hospital expanded by 70%, providing space for relocating key services-the rapid response team, medical on-call team, and nursing supervision. Initial observations suggested a shared workspace layout based on anecdotal evidence. Method: Stakeholders have reached a consensus on a three-stage process to assess the suitability of a shared workspace layout for these services: first, collecting data on social interactions with a focus on resilience abilities; second, presenting layout alternatives based on sociograms; and third, evaluating these alternatives and devising a strategy for allocating personnel to shifts based on a resilience score derived from social network metrics. Case Study: The examination of social network metrics allowed identifying key individuals contributing to the overall resilience of the three services. Sociograms provided visual representations of how these individuals were spatially distributed within the shared layout. Discussion: The process was designed to shape a resilient layout and incorporated initial data, preferences, and constraints into layout proposals. Additionally, it utilized a resilience score from existing literature to formulate a strategy for staff allocation to shifts, ensuring consistent collective resilience ability across all shifts.

Functional and structural brain connectivity in disorders of consciousness.

Brain connectivity, allowing information to be shared between distinct cortical areas and thus to be processed in an integrated way, has long been considered critical for consciousness. However, the relationship between functional intercortical interactions and the structural connections thought to underlie them is poorly understood. In the present work, we explore both functional (with an EEG-based metric: the median weighted symbolic mutual information in the theta band) and structural (with a brain MRI-based metric: fractional anisotropy) connectivities in a cohort of 78 patients with disorders of consciousness. Both metrics could distinguish patients in a vegetative state from patients in minimally conscious state. Crucially, we discovered a significant positive correlation between functional and structural connectivities. Furthermore, we showed that this structure-function relationship is more specifically observed when considering structural connectivity within the intra- and inter-hemispheric long-distance cortico-cortical bundles involved in the Global Neuronal Workspace (GNW) theory of consciousness, thus supporting predictions of this model. Altogether, these results support the interest of multimodal assessments of brain connectivity in refining the diagnostic evaluation of patients with disorders of consciousness.

The influence of feature-based attention and response requirements on ERP correlates of auditory awareness.

In search for the neural correlates of consciousness (NCCs), it is important to isolate the true NCCs from their prerequisites, consequences, and co-occurring processes. To date, little is known about how attention affects the event-related potential (ERP) correlates of auditory awareness and there is contradictory evidence on whether one of them, the late positivity (LP), is affected by response requirements. By implementing a GO-NOGO design with target and nontarget stimuli, we controlled for feature-based attention and response requirements in the same experiment, while participants rated their awareness using a perceptual awareness scale. The results showed a prolonged auditory awareness negativity (AAN) for aware trials, which was influenced neither by attention nor by response requirement. The LP was affected by both attention and response requirements. Consistent with the levels of processing hypothesis, the LP was related to consciousness as a correlate of the processing of higher-level stimulus features, likely requiring access to a "global workspace." Our findings further suggest that AAN is a proper ERP correlate of auditory consciousness and thus a true NCC in the auditory modality.

A synergistic workspace for human consciousness revealed by Integrated Information Decomposition.

How is the information-processing architecture of the human brain organised, and how does its organisation support consciousness? Here, we combine network science and a rigorous information-theoretic notion of synergy to delineate a 'synergistic global workspace', comprising gateway regions that gather synergistic information from specialised modules across the human brain. This information is then integrated within the workspace and widely distributed via broadcaster regions. Through functional MRI analysis, we show that gateway regions of the synergistic workspace correspond to the human brain's default mode network, whereas broadcasters coincide with the executive control network. We find that loss of consciousness due to general anaesthesia or disorders of consciousness corresponds to diminished ability of the synergistic workspace to integrate information, which is restored upon recovery. Thus, loss of consciousness coincides with a breakdown of information integration within the synergistic workspace of the human brain. This work contributes to conceptual and empirical reconciliation between two prominent scientific theories of consciousness, the Global Neuronal Workspace and Integrated Information Theory, while also advancing our understanding of how the human brain supports consciousness through the synergistic integration of information.

The human brain consists of billions of neurons which process sensory inputs, such as sight and sound, and combines them with information already stored in the brain. This integration of information guides our decisions, thoughts, and movements, and is hypothesized to be integral to consciousness. However, it is poorly understood how the brain regions responsible for processing this integration are organized in the brain. To investigate this question, Luppi et al. employed a mathematical framework called Partial Information Decomposition (PID) which can distinguish different types of information: redundancy (available from many regions) and synergy (which reflects genuine integration). The team applied the PID framework to the brain scans of 100 individuals. This allowed them to identify which brain regions combine information from across the brain (known as gateways), and which ones transmit it back to the rest of the brain (known as broadcasters). Next, Luppi et al. set out to find how these regions compared in unconscious and conscious individuals. To do this, they studied 15 healthy volunteers whose brains were scanned (using a technique called functional MRI) before, during, and after anaesthesia. This revealed that the brain integrated less information when unconscious, and that this reduction happens predominantly in gateway rather than broadcaster regions. The same effect was also observed in the brains of individuals who were permanently unconscious due to brain injuries. These findings provide a way of understanding how information is organised in the brain. They also suggest that loss of consciousness due to brain injuries and anaesthesia involve similar brain circuits. This means it may be possible to gain insights about disorders of consciousness from studying how people emerge from anaesthesia.

Design and evaluation of a global workspace agent embodied in a realistic multimodal environment.

As the apparent intelligence of artificial neural networks (ANNs) advances, they are increasingly likened to the functional networks and information processing capabilities of the human brain. Such comparisons have typically focused on particular modalities, such as vision or language. The next frontier is to use the latest advances in ANNs to design and investigate scalable models of higher-level cognitive processes, such as conscious information access, which have historically lacked concrete and specific hypotheses for scientific evaluation. In this work, we propose and then empirically assess an embodied agent with a structure based on global workspace theory (GWT) as specified in the recently proposed "indicator properties" of consciousness. In contrast to prior works on GWT which utilized single modalities, our agent is trained to navigate 3D environments based on realistic audiovisual inputs. We find that the global workspace architecture performs better and more robustly at smaller working memory sizes, as compared to a standard recurrent architecture. Beyond performance, we perform a series of analyses on the learned representations of our architecture and share findings that point to task complexity and regularization being essential for feature learning and the development of meaningful attentional patterns within the workspace.

Design and evaluation of a symmetric amplification mechanism based anthropomorphic shoulder.

Shoulder joints determine the motion range of the upper limb. Thus, the compact and well-stiffened spherical parallel mechanism (SPM) has emerged as the mainstream shoulder prosthesis design approaches. However, the SPM's moving pairs of redundant motions impose excessive constraints that limit its workspace. Therefore, amplifying the workspace of the SPM to cover the motion range required by human daily activities is a pressing problem in shoulder prosthesis design. To address this challenge, this study proposed a workspace amplification approach through the kinematic analysis of a symmetrically arranged 2 degrees of freedom (DoFs) passive mechanism, together with the designed and optimized 3-RRR SPM, to construct an anthropomorphic shoulder. The effectiveness and reliability of the proposed mechanism was verified through thorough analyses. Simulation and experiment results demonstrated that the workspace amplification mechanism could significantly increase the maximum motion match index between the shoulder prosthesis and the daily workspace of the human shoulder from only 26.3% to 94.79%, solving the problem that the traditional SPM-based prostheses cannot satisfy the motion range required by daily activities. Moreover, the proposed mechanism has the potential to amplify the workspace of most parallel mechanisms with multiple DoFs after proper modification.

Toward a universal theory of consciousness.

While falsifiability has been broadly discussed as a desirable property of a theory of consciousness, in this paper, we introduce the meta-theoretic concept of "Universality" as an additional desirable property for a theory of consciousness. The concept of universality, often assumed in physics, posits that the fundamental laws of nature are consistent and apply equally everywhere in the universe and remain constant over time. This assumption is crucial in science, acting as a guiding principle for developing and testing theories. When applied to theories of consciousness, universality can be defined as the ability of a theory to determine whether any fully described dynamical system is conscious or non-conscious. Importantly, for a theory to be universal, the determinant of consciousness needs to be defined as an intrinsic property of a system as opposed to replying on the interpretation of the external observer. The importance of universality originates from the consideration that given that consciousness is a natural phenomenon, it could in principle manifest in any physical system that satisfies a certain set of conditions whether it is biological or non-biological. To date, apart from a few exceptions, most existing theories do not possess this property. Instead, they tend to make predictions as to the neural correlates of consciousness based on the interpretations of brain functions, which makes those theories only applicable to brain-centric systems. While current functionalist theories of consciousness tend to be heavily reliant on our interpretations of brain functions, we argue that functionalist theories could be converted to a universal theory by specifying mathematical formulations of the constituent concepts. While neurobiological and functionalist theories retain their utility in practice, we will eventually need a universal theory to fully explain why certain types of systems possess consciousness.

The use of digital tools in rare neurological diseases towards a new care model: a narrative review.

Rare neurological diseases as a whole share peculiar features as motor and/or cognitive impairment, an elevated disability burden, a frequently chronic course and, in present times, scarcity of therapeutic options. The rarity of those conditions hampers both the identification of significant prognostic outcome measures, and the development of novel therapeutic approaches and clinical trials. Collection of objective clinical data through digital devices can support diagnosis, care, and therapeutic research. We provide an overview on recent developments in the field of digital tools applied to rare neurological diseases, both in the care setting and as providers of outcome measures in clinical trials in a representative subgroup of conditions, including ataxias, hereditary spastic paraplegias, motoneuron diseases and myopathies.

Unlocking educational frontiers: Exploring higher educators' adoption of google workspace technology tools for teaching and assessment in Lesotho dynamic landscape.

The rapid integration of google workspace tools in higher education has the potential to transform education. To fully realize this potential, it is crucial to understand the factors that influence educators' attitudes and intentions toward adopting these tools. However, current research has mainly focused on specific contexts, highlighting the need for a comprehensive examination in different educational settings. This study delves into the complexities of the Technology Acceptance Model and expands its scope by considering additional external variables. Data was collected through an online survey, with 396 educators sharing their perspectives and intentions regarding google workspace tools. We used composite-based structural equation modeling, implemented by the SEMinR package in the R programming language, to rigorously assess the measurement and structural models of the constructs. The study's findings reveal significant relationships among the factors that shape educators' perceptions and behaviors in relation to google workspace tools. Notably, all paths show significant influence, except those connecting social influence to perceived usefulness and ease of use to attitude. Additionally, the research identifies the moderating impacts of gender, which do not significantly contribute to the observed relationships. This study contributes substantially to the growing knowledge of technology adoption in higher education. Furthermore, it offers valuable insights that can benefit educators, institutions, and policymakers who want to leverage the potential of google workspace tools for teaching and assessment. Lastly, the study provides clear directions for future research in this area.

A global neuronal workspace model of functional neurological disorders.

We introduce here a general model of Functional Neurological Disorders based on the following hypothesis: a Functional Neurological Disorder could correspond to a consciously initiated voluntary top-down process causing involuntary lasting consequences that are consciously experienced and subjectively interpreted by the patient as involuntary. We develop this central hypothesis according to Global Neuronal Workspace theory of consciousness, that is particularly suited to describe interactions between conscious and non-conscious cognitive processes. We then present a list of predictions defining a research program aimed at empirically testing their validity. Finally, this general model leads us to reinterpret the long-debated links between hypnotic suggestion and functional neurological disorders. Driven by both scientific and therapeutic goals, this theoretical paper aims at bringing closer the psychiatric and neurological worlds of functional neurological disorders with the latest developments of cognitive neuroscience of consciousness.

A measure centrality index for systematic empirical comparison of consciousness theories.

Consciousness science is marred by disparate constructs and methodologies, making it challenging to systematically compare theories. This foundational crisis casts doubts on the scientific character of the field itself. Addressing it, we propose a framework for systematically comparing consciousness theories by introducing a novel inter-theory classification interface, the Measure Centrality Index (MCI). Recognizing its gradient distribution, the MCI assesses the degree of importance a specific empirical measure has for a given consciousness theory. We apply the MCI to probe how the empirical measures of the Global Neuronal Workspace Theory (GNW), Integrated Information Theory (IIT), and Temporospatial Theory of Consciousness (TTC) would fare within the context of the other two. We demonstrate that direct comparison of IIT, GNW, and TTC is meaningful and valid for some measures like Lempel-Ziv Complexity (LZC), Autocorrelation Window (ACW), and possibly Mutual Information (MI). In contrast, it is problematic for others like the anatomical and physiological neural correlates of consciousness (NCC) due to their MCI-based differential weightings within the structure of the theories. In sum, we introduce and provide proof-of-principle of a novel systematic method for direct inter-theory empirical comparisons, thereby addressing isolated evolution of theories and confirmatory bias issues in the state-of-the-art neuroscience of consciousness.

Anesthesia and the neurobiology of consciousness.

In the 19th century, the discovery of general anesthesia revolutionized medical care. In the 21st century, anesthetics have become indispensable tools to study consciousness. Here, I review key aspects of the relationship between anesthesia and the neurobiology of consciousness, including interfaces of sleep and anesthetic mechanisms, anesthesia and primary sensory processing, the effects of anesthetics on large-scale functional brain networks, and mechanisms of arousal from anesthesia. I discuss the implications of the data derived from the anesthetized state for the science of consciousness and then conclude with outstanding questions, reflections, and future directions.

Long-Travel 3-PRR Parallel Platform Based on Biomimetic Variable-Diameter Helical Flexible Hinges.

Technological advancements across various sectors are driving a growing demand for large-scale three-degree-of-freedom micro-nano positioning platforms, with substantial pressure to reduce footprints while enhancing motion range and accuracy. This study proposes a three-prismatic-revolute-revolute (3-PRR) parallel mechanism based on biomimetic variable-diameter helical flexible hinges. The resulting platform achieves high-precision planar motion along the X- and Y-axes, a centimeter-level translation range, and a rotational range of 35° around the Z-axis by integrating six variable-diameter flexible helical hinges that serve as rotational joints when actuated by three miniature linear servo drives. The drives are directly connected to the moving platform, thereby enhancing the compactness of the system. A kinematic model of the motion platform was established, and the accuracy and effectiveness of the forward and inverse kinematic solutions were validated using finite element analysis. Finally, a prototype of the 3-PRR parallel platform was fabricated, and its kinematic performance was experimentally verified visually for improved endpoint displacement detection. The assessment results revealed a maximum displacement error of 9.5% and confirmed that, judging by its favorable workspace-to-footprint ratio, the final system is significantly more compact than those reported in the literature.

Design Optimization of a Soft Robotic Rehabilitation Glove Based on Finger Workspace Analysis.

The finger workspace is crucial for performing various grasping tasks. Thus, various soft rehabilitation gloves have been developed to assist individuals with paralyzed hands in activities of daily living (ADLs) or rehabilitation training. However, most soft robotic glove designs are insufficient to assist with various hand postures because most of them use an underactuated mechanism for design simplicity. Therefore, this paper presents a methodology for optimizing the design of a high-degree-of-freedom soft robotic glove while not increasing the design complexity. We defined the required functional workspace of the index finger based on ten frequently used grasping postures in ADLs. The design optimization was achieved by simulating the proposed finger-robot model to obtain a comparable workspace to the functional workspace. In particular, the moment arm length for extension was optimized to facilitate the grasping of large objects (precision disk and power sphere), whereas a torque-amplifying routing design was implemented to aid the grasping of small objects (lateral pinch and thumb-two-finger pinch). The effectiveness of the optimized design was validated through testing with a stroke survivor and comparing the assistive workspace. The observed workspace demonstrated that the optimized glove design could assist with nine out of the ten targeted grasping posture functional workspaces. Furthermore, the assessment of the grasping speed and force highlighted the glove's usability for various rehabilitation activities. We also present and discuss a generalized methodology to optimize the design parameters of a soft robotic glove that uses an underactuated mechanism to assist the targeted workspace. Overall, the proposed design optimization methodology serves as a tool for developing advanced hand rehabilitation robots, as it offers insight regarding the importance of routing optimization in terms of the workspace.

Assessing the commensurability of theories of consciousness: On the usefulness of common denominators in differentiating, integrating and testing hypotheses.

How deep is the current diversity in the panoply of theories to define consciousness, and to what extent do these theories share common denominators? Here we first examine to what extent different theories are commensurable (or comparable) along particular dimensions. We posit logical (and, when applicable, empirical) commensurability as a necessary condition for identifying common denominators among different theories. By consequence, dimensions for inclusion in a set of logically and empirically commensurable theories of consciousness can be proposed. Next, we compare a limited subset of neuroscience-based theories in terms of commensurability. This analysis does not yield a denominator that might serve to define a minimally unifying model of consciousness. Theories that seem to be akin by one denominator can be remote by another. We suggest a methodology of comparing different theories via multiple probing questions, allowing to discern overall (dis)similarities between theories. Despite very different background definitions of consciousness, we conclude that, if attention is paid to the search for a common methological approach to brain-consciousness relationships, it should be possible in principle to overcome the current Babylonian confusion of tongues and eventually integrate and merge different theories.

Prevalence of computer vision syndrome: A systematic review and meta-analysis.

PURPOSE: This review aimed to estimate the prevalence of computer vision syndrome (CVS) in the general population and subgroups. METHODS: A search was conducted in the following the databases: PubMed, SCOPUS, EMBASE, and Web of Science until February 13, 2023. We included studies that assessed the prevalence of CVS in any population. The Joanna Briggs Institute's critical appraisal tool was used to evaluate the methodological quality. A meta-analysis of the prevalence of CVS was done using a random-effects model, assessing the sources of heterogeneity using subgroup and meta-regression analyses. RESULTS: A total of 103 cross-sectional studies with 66 577 participants were included. The prevalence of CVS was 69.0% (95% CI: 62.3 to 75.3; I2: 99.7%), ranging from 12.1 to 97.3% across studies. Point prevalence was higher in women than in men (71.4 vs. 61.8%), university students (76.1%), Africa (71.2%), Asia (69.9%), contact lens wearers (73.1% vs. 63.8%) in studies conducted before the COVID-19 pandemic (72.8%), and in those that did not use the CVS-Q questionnaire (75.4%). In meta-regression, using the CVS-Q scale was associated with a lower prevalence of CVS. CONCLUSION: Seven out of ten people suffer from CVS. Preventive strategies and interventions are needed to decrease the prevalence of this condition which can affect productivity and quality of life. Future studies should standardize a definition of CVS.

Are emergency departments leader identity workspaces? A qualitative study of emergency physicians.

OBJECTIVE: Emergency medicine is a discipline with complex leadership demands, which are experienced by junior and senior emergency physicians alike. In this environment, emergency physicians can struggle to work out what it means to be a leader and develop professional identities as leaders, necessitating a leader identity workspace. The aim of the present study is to explore whether emergency physicians view their work environment as leader identity workspaces. METHODS: An online qualitative survey was used that included open-ended questions about emergency physicians' experience of their workplace as a 'space' to craft their leadership identity. Participants' responses were analysed using reflexive thematic analysis. RESULTS: Three themes, comprising several subthemes, were identified that related to emergency physicians' ideal leader selves (leader dreams and desired leader selves), their experience of the community of clinicians in hospitals (confrontational sentient communities) and the types of rituals emergency physicians yearn for to support and legitimate their leadership (seeking vital leadership rites of passage). CONCLUSION: Our results suggest that neither EDs nor hospitals more generally exhibit the properties of, or are experienced by emergency physicians, as leader identity workspaces.

Anesthesia Workspaces for Safe Medication Practices: Design Guidelines.

BACKGROUND: Studies show that workspace for the anesthesia providers is prone to interruptions and distractions. Anesthesia providers experience difficulties while performing critical medication tasks such as medication preparation and administration due to poor ergonomics and configurations of workspace, equipment clutter, and limited space which ultimately may impact patient safety, length of surgery, and cost of care delivery. Therefore, improving design of anesthesia workspace for supporting safe and efficient medication practices is paramount. OBJECTIVES: The objective of this study was to develop a set of evidence-based design guidelines focusing on design of anesthesia workspace to support safer anesthesia medication tasks in operating rooms (ORs). METHODS: Data collection was based on literature review, observation, and coding of more than 30 prerecorded videos of outpatient surgical procedures to identify challenges experienced by anesthesia providers while performing medication tasks. Guidelines were then reviewed and validated using short survey. RESULTS: Findings are summarized into seven evidence-based design guidelines, including (1) locate critical tasks within a primary field of vision, (2) eliminate travel into and through the anesthesia zone (for other staff), (3) identify and demarcate a distinct anesthesia zone with adequate space for the anesthesia provider, (4) optimize the ability to reposition/reconfigure the anesthesia workspace, (5) minimize clutter from equipment, (6) provide adequate and appropriately positioned surfaces for medication preparation and administration, and (7) optimize task and surface lighting. CONCLUSION: This study finds many areas for improving design of ORs. Improvements of anesthesia work area will call for contribution and cooperation of entire surgical team.

Evaluation of Upper Extremity Reachable Workspace in Children With Brachial Plexus Birth Injury.

PURPOSE: Brachial plexus birth injury (BPBI) results in upper extremity (UE) movement limitations. Current assessments of UE function used to inform clinical decision-making only evaluate a limited set of static postures and/or movements and have been criticized for being insensitive to certain meaningful differences in function. Reachable workspace provides a numeric and visual assessment of global UE movement ability by quantifying the regions in space that patients can reach with their hands, and it can be collected using real-time feedback to elicit a best-effort acquisition of function. This study evaluated the ability of a real-time feedback reachable workspace tool to assess UE movement in BPBI. METHODS: Twenty-two children with BPBI participated. Reachable workspace data were collected with three-dimensional motion capture using real-time visual feedback to measure UE reaching ability in all regions surrounding the body. All outer, far-from-body points reached by the hand were recorded and analyzed by region. A two-way, within-subjects analysis of variance was used to assess interlimb differences in percentage workspace reached and median reach distance for each of the six regions. RESULTS: The affected limb had significantly less percentage workspace reached than the unaffected limb for all six regions (mean interlimb differences by region, 5.7%-38.6%). The affected limb had significantly less median reach distance than the unaffected limb for all six regions (mean interlimb differences by region, 3.1%-36.8%). CONCLUSIONS: The workspace approach was capable of detecting UE movement impairments of the BPBI-affected limb. The reported deficits in workspace on the affected limb correspond to common movement impairments in BPBI, such as limitations in shoulder elevation, external rotation, extension, and elbow extension. CLINICAL RELEVANCE: The real-time feedback reachable workspace tool is sufficiently robust for assessing UE movement impairments in children with BPBI.