Multiple Levels Research Articles

Improved Topology and Control Strategies for DC Converters in Wind Power Full DC Systems

This study presents an enhanced composite modular DC/DC converter topology designed to address critical technical requirements in wind power full DC systems, including high capacity, high conversion ratio, and fault isolation. The proposed topology combines MMC circuits and module combination circuits, allowing for exceptional modularity and configurability. Through the serial and parallel connection of multiple modules, the voltage or current levels can be further enhanced. Regarding the control strategy, the paper adopts SOGI phase-locked and coordinate transformation technology to precisely measure and control the differential and common-mode voltages within the MMC modules. A mathematical model is established, providing a theoretical foundation for experimental analysis. The research emphasizes the implementation of key strategies such as circulating current suppression, nearest level approximation, and capacitor voltage sorting. To validate the practicality and effectiveness of the proposed converter topology and control strategy, an experiment is conducted using a ±30 kV/±300 kV, 300 MW model constructed within the MATLAB/Simulink simulation environment.

Childhood obesity prevention in general practice: supporting implementation through co-ideation.

Childhood obesity is associated with physical and psychological complications thus the prevention of excess weight gain in childhood is an important health goal. Relevant to the prevention of childhood obesity, Australian general practice-specific, preventive care guidelines recommend General Practitioners (GPs) conduct growth monitoring and promote a number of healthy behaviours. However, challenges to providing preventive care in general practice may impact implementation. In October and November, 2022, a series of three workshops focusing on the prevention of childhood obesity were held with a group of Australian GPs and academics. The objective of the workshops was to determine practical ways that GPs can be supported to address barriers to the incorporation of obesity-related prevention activities into their clinical practice, for children with a healthy weight. This paper describes workshop proceedings, specifically the outcomes of co-ideation activities that included idea generation, expansion of the ideas to possible interventions, and the preliminary assessment of these concepts. The ecological levels of the individual, interpersonal, and organisation were considered. Possible opportunities to support childhood obesity prevention were identified at multiple ecological levels within the clinic. The preliminary list of proposed interventions to facilitate action included GP education and training, clinical audit facilitation, readily accessible clinical guidelines with linked resources, a repository of resources, and provision of adequate growth monitoring tools in general practice. Co-ideation with GPs resulted in a number of proposed interventions, informed by day-to-day practicalities, to support both guideline implementation and childhood obesity prevention in general practice.

The CDK Pho85 inhibits Whi7 Start repressor to promote cell cycle entry in budding yeast.

Pho85 is a multifunctional CDK that signals to the cell when environmental conditions are favorable. It has been connected to cell cycle control, mainly in Start where it promotes the G1/S transition. Here we describe that the Start repressor Whi7 is a key target of Pho85 in the regulation of cell cycle entry. The phosphorylation of Whi7 by Pho85 inhibits the repressor and explains most of the contribution of the CDK in the activation of Start. Mechanistically, Pho85 downregulates Whi7 protein levels through the control of Whi7 protein stability and WHI7 gene transcription. Whi7 phosphorylation by Pho85 also restrains the intrinsic ability of Whi7 to associate with promoters. Furthermore, although Whi5 is the main Start repressor in normal cycling cells, in the absence of Pho85, Whi7 becomes the major repressor leading to G1 arrest. Overall, our results reveal a novel mechanism by which Pho85 promotes Start through the regulation of the Whi7 repressor at multiple levels, which may confer to Whi7 a functional specialization to connect the response to adverse conditions with the cell cycle control.

A constitutional reflector? Assessing societal and digital constitutionalism in Meta’s Oversight Board

Abstract This article explores the use of constitutional narratives in social media platform governance, addressing the concept of digital constitutionalism. It aims to elucidate how digital constitutionalism manifests in platforms and the implications for democratizing these governance environments. It argues that digital constitutionalism exposes three goals toward platform governance: (1) an analogous application of constitutional values in private landscapes; (2) an ideological framework permeating multiple normativity levels; and (3) a policy consideration framing the symmetry of regulatory efforts with fundamental values. These three objectives hinge on a liberal and normative approach to constitutionalism, detaching from the political and social considerations at the centre of constitutional democracy. The article argues that this leads to extensive legitimacy issues when considering the transnational character of social media platforms and the localized issues of its users, as explored through an analysis of Meta’s Oversight Board. It is argued that a societal perspective of (digital) constitutionalism must guide the institution’s goals and procedures to promote legitimacy and accountability. This societal approach exposes the reliability issues of the established self-referencing system. It also allows an analysis of the hybridization of traditional constitutional principles in the emerging societal constitution developed by the corporation.

Phosphatase to kinase switch of a critical enzyme contributes to timing of cell differentiation.

The process of cell differentiation is highly regulated in both prokaryotic and eukaryotic organisms. The aquatic bacterium, Caulobacter crescentus, undergoes programmed cell differentiation from a motile swarmer cell to a stationary stalked cell with each cell cycle. This critical event is regulated at multiple levels. Kinase activity of the bifunctional enzyme, PleC, is limited to a brief period when it initiates the molecular signaling cascade that results in cell differentiation. Conversely, PleC phosphatase activity is required for pili formation and flagellar rotation. We show that PleC is localized to the flagellar pole by the scaffold protein, PodJ, which is known to suppress PleC kinase activity in vitro. PleC mutants that are unable to bind PodJ have increased kinase activity in vivo, resulting in premature differentiation. We propose a model in which PodJ regulation of PleC's enzymatic activity contributes to the robust timing of cell differentiation during the Caulobacter cell cycle.

Rapid cycle deliberate practice to improve airway skills and performance of trainees in a pediatric emergency department.

The study objective was to determine the effect of a rapid cycle deliberate practice (RCDP) program on simulated and actual airway skills by pediatric emergency medicine (PEM) fellows. We designed and implemented a 12-month RCDP airway skills curriculum for PEM fellows at an academic pediatric institution. The curriculum was designed using airway training literature, RCDP principals, and internal quality assurance airway video review program. Simulation training scenarios increased in complexity throughout the curriculum. PEM fellows participated in monthly sessions. Two PEM faculty facilitated the sessions, utilizing a step-by-step objective structured clinical evaluation (OSCE)-style tool for each scenario. Data were collected for all four levels of the Kirkpatrick Model of Training Evaluation-participant response (reaction, pre-post session survey), skills performance in the simulation setting (learning, pre-post OSCE), skills performance for actual patients (behavior, video review), and patient outcomes (results, video review). During the study period (August 2021 to June 2022), 13 PEM fellows participated in 112 sessions (mean nine sessions per fellow). PEM fellows reported improved comfort in all domains of airway management, including intubation performance. Participant OSCE scores improved posttraining (pretraining median score for trainees 57 [IQR 57-59], posttraining median 61 [IQR 61-62], p = 0.0005). Over the 12 months, PEM fellows performed 45 intubation attempts in the pediatric emergency department (median patient age 4 years [IQR 1-9 years]). Compared to a 5-year historical cohort, participants had higher first-pass success (87% vs. 71%, p = 0.028) and shorter attempt duration (22 s vs. 29 s, p = 0.018). There was no significant difference in the frequency of oxyhemoglobin desaturation in the training period versus the historical period (7% vs. 15%, p = 0.231). At multiple levels of educational outcomes, including participant behavior and patient outcomes, an RCDP program was associated with improved airway skills and performance of PEM fellows.

The time-evolving epileptic brain network: concepts, definitions, accomplishments, perspectives.

Epilepsy is now considered a network disease that affects the brain across multiple levels of spatial and temporal scales. The paradigm shift from an epileptic focus-a discrete cortical area from which seizures originate-to a widespread epileptic network-spanning lobes and hemispheres-considerably advanced our understanding of epilepsy and continues to influence both research and clinical treatment of this multi-faceted high-impact neurological disorder. The epileptic network, however, is not static but evolves in time which requires novel approaches for an in-depth characterization. In this review, we discuss conceptual basics of network theory and critically examine state-of-the-art recording techniques and analysis tools used to assess and characterize a time-evolving human epileptic brain network. We give an account on current shortcomings and highlight potential developments towards an improved clinical management of epilepsy.

Linear and nonlinear receptivity mechanisms in boundary layers subject to free-stream turbulence

Large-eddy simulations of a flat-plate boundary layer, without a leading edge, subject to multiple levels of incoming free-stream turbulence are considered in the present work. Within an input–output model, where nonlinear terms of the incompressible Navier–Stokes equations are treated as an external forcing, we manage to separate inputs related to perturbations coming through the intake of the numerical domain, whose evolution represents a linear mechanism, and the volumetric nonlinear forcing due to triadic interactions. With these, we perform the full reconstruction of the statistics of the flow, as measured in the simulations, to quantify pairs of wavenumbers and frequencies more affected by either linear or nonlinear receptivity mechanisms. Inside the boundary layer, different wavenumbers at near-zero frequency reveal streaky structures. Those that are amplified predominantly via linear interactions with the incoming vorticity occur upstream and display transient growth, while those generated by the nonlinear forcing are the most energetic and appear in more downstream positions. The latter feature vortices growing proportionally to the laminar boundary layer thickness, along with a velocity profile that agrees with the optimal amplification obtained by linear transient growth theory. The numerical approach presented is general and could potentially be extended to any simulation for which receptivity to incoming perturbations needs to be assessed.

An analysis of the Aesthetics in Horror Artworks

Aesthetics in horror art works is also an important field of aesthetic research. The study of color, image, emotion, music and so on of horror art works also collide with unexpected sparks and make people feel the unique charm. This paper takes one of Lin Zhengying's masterpieces, "New Mr. Zombie", as an example, and analyzes it from multiple dimensions and levels of the film to explore the aesthetics in horror artworks and the unique artistic charm it gives.

STICAP : Spatio-temporal Interactive Attention for Citywide Crowd Activity Prediction

Accurate citywide crowd activity prediction (CAP) can enable proactive crowd mobility management and timely responses to urban events, which has become increasingly important for a myriad of smart city planning and management purposes. However, complex correlations across the crowd activities, spatial and temporal urban environment features and their interactive dependencies, and relevant external factors (e.g., weather conditions) make it highly challenging to predict crowd activities accurately in terms of different venue categories (for instance, venues related to dining, services, and residence) and varying degrees (e.g., daytime and nighttime). To address the above concerns, we propose STICAP , a citywide spatio-temporal interactive crowd activity prediction approach. In particular, STICAP takes in the location-based social network check-in data (e.g., from Foursquare/Gowalla) as the model inputs and forecasts the crowd activity within each time step for each venue category. Furthermore, we have integrated multiple levels of temporal discretization to interactively capture the relations with historical data. Then, three parallel Residual Spatial Attention Networks ( RSAN ) in the Spatial Attention Component exploit the hourly, daily, and weekly spatial features of crowd activities, which are further fused and processed by the Temporal Attention Component for interactive CAP . Along with other external factors such as weather conditions and holidays, STICAP adaptively and accurately forecasts the final crowd activities per venue category, enabling potential activity recommendation and other smart city applications. Extensive experimental studies based on three different real-world crowd activity datasets have demonstrated that our proposed STICAP outperforms the baseline and state-of-the-art algorithms in CAP accuracy, with an average error reduction of 35.02%.

Experiences of alcohol use during pregnancy: A qualitative study of pregnant women at risk of acquiring HIV in Cape Town, South Africa

In South Africa, alcohol use during pregnancy is prevalent and associated with increased HIV risk. Developing locally sensitive and contextually appropriate evidence-based interventions to address alcohol use among pregnant and breastfeeding women in South Africa requires comprehensive understanding of the context of perinatal alcohol use and how relationships and lived environments may serve as barriers or supports for alcohol reduction. We conducted twenty in-depth qualitative interviews with isiXhosa speaking women who reported alcohol use during their recent pregnancy and/or recent intimate partner violence in Cape Town, South Africa between September and November 2022. We describe patterns and drivers of ongoing alcohol use during pregnancy and map them onto levels of the socioecological model. Data were analyzed utilizing the interpretivist paradigm and interpretive thematic analysis. Eight women reported alcohol use during pregnancy, sixteen reported experiencing recent IPV, and four women reported both alcohol use during pregnancy and recent IPV. In interviews, commonly cited reasons for continued alcohol use in pregnancy included stress (e.g., due to financial concerns), peer pressure, the central role of alcohol use in socialization and the persistence of misconceptions regarding the safety of alcohol use in pregnancy. Still, despite women reporting social norms that supported continued alcohol use in pregnancy, many altered who they drank with due to fear of judgement from close friends and family, leaving them isolated from their social support system. Interventions aimed at increasing interpersonal support, such as the use of peer mentors, could prove beneficial. Although the clinic provides messaging around the harms of alcohol use in pregnancy, these messages conflict with messaging received from their peers, limiting their impact on behavior. Locally sensitive tailored, relevant programming that intervenes on barriers to reducing alcohol use in pregnancy at multiple levels of the socioeconomic model are vital to effectively addressing this public health issue.

'Against all floods': plant adaptation to flooding stress and combined abiotic stresses.

Current climate change brings with it a higher frequency of environmental stresses, which occur in combination rather than individually leading to massive crop losses worldwide. In addition to, for example, drought stress (low water availability), also flooding (excessive water) can threaten the plant, causing, among others, an energy crisis due to hypoxia, which is responded to by extensive transcriptional, metabolic and growth-related adaptations. While signalling during flooding is relatively well understood, at least in model plants, the molecular mechanisms of combinatorial flooding stress responses, for example, flooding simultaneously with salinity, temperature stress and heavy metal stress or sequentially with drought stress, remain elusive. This represents a significant gap in knowledge due to the fact that dually stressed plants often show unique responses at multiple levels not observed under single stress. In this review, we (i) consider possible effects of stress combinations from a theoretical point of view, (ii) summarize the current state of knowledge on signal transduction under single flooding stress, (iii) describe plant adaptation responses to flooding stress combined with four other abiotic stresses and (iv) propose molecular components of combinatorial flooding (hypoxia) stress adaptation based on their reported dual roles in multiple stresses. This way, more future emphasis may be placed on deciphering molecular mechanisms of combinatorial flooding stress adaptation, thereby potentially stimulating development of molecular tools to improve plant resilience towards multi-stress scenarios.

GIGANTEA Unveiled: Exploring Its Diverse Roles and Mechanisms.

GIGANTEA (GI) is a conserved nuclear protein crucial for orchestrating the clock-associated feedback loop in the circadian system by integrating light input, modulating gating mechanisms, and regulating circadian clock resetting. It serves as a core component which transmits blue light signals for circadian rhythm resetting and overseeing floral initiation. Beyond circadian functions, GI influences various aspects of plant development (chlorophyll accumulation, hypocotyl elongation, stomatal opening, and anthocyanin metabolism). GI has also been implicated to play a pivotal role in response to stresses such as freezing, thermomorphogenic stresses, salinity, drought, and osmotic stresses. Positioned at the hub of complex genetic networks, GI interacts with hormonal signaling pathways like abscisic acid (ABA), gibberellin (GA), salicylic acid (SA), and brassinosteroids (BRs) at multiple regulatory levels. This intricate interplay enables GI to balance stress responses, promoting growth and flowering, and optimize plant productivity. This review delves into the multifaceted roles of GI, supported by genetic and molecular evidence, and recent insights into the dynamic interplay between flowering and stress responses, which enhance plants' adaptability to environmental challenges.

Multi-granularity retrieval of mineral resource geological reports based on multi-feature association

Massive geologic report contains all kinds of multimodal geologic data information (geologic text, geologic maps, geologic tables, etc.), which contain a lot of rich geologic basic knowledge and expert experience knowledge about rocks and minerals, stratigraphic structure, geologic age, geographic location, and so on. Accurate retrieval of specific information from massive geologic data has become an important need for geologic information retrieval. However, the majority of existing research primarily revolves around extracting and associating information at a single granularity to facilitate geological semantic retrieval, which ignores many potential semantic associations, leading to ambiguity and fuzziness in semantic retrieval. To solve these problems, this paper proposes a multi-granularity (document-chapter-paragraph) geological information retrieval framework for accurate semantic retrieval. The framework firstly extracts topic feature information, spatiotemporal feature information, figure and table feature information based on the multi-granularity of geological reports. Then, an improved apriori algorithm is used to mine and visualize the associations among the feature information to discover the semantic associations of the geological reports at multiple levels of granularity. Finally, experiments are designed to validate the application of the proposed multi-granularity information retrieval framework on the accurate retrieval of geological reports. The experimental results show that the proposed multi-granularity information retrieval framework in this paper can dig deeper into underlying geo-semantic information and realize accurate retrieval.

Comprehensive Assessment of Graphene Oxide Nanoparticles: Effects on Liver Enzymes and Cardiovascular System in Animal Models and Skeletal Muscle Cells.

The growing interest in graphene oxide (GO) for different biomedical applications requires thoroughly examining its safety. Therefore, there is an urgent need for reliable data on how GO nanoparticles affect healthy cells and organs. In the current work, we adopted a comprehensive approach to assess the influence of GO and its polyethylene glycol-modified form (GO-PEG) under near-infrared (NIR) exposure on several biological aspects. We evaluated the contractility of isolated frog hearts, the activity of two rat liver enzymes-mitochondrial ATPase and diamine oxidase (DAO), and the production of reactive oxygen species (ROS) in C2C12 skeletal muscle cells following direct exposure to GO nanoparticles. The aim was to study the influence of GO nanoparticles at multiple levels-organ; cellular; and subcellular-to provide a broader understanding of their effects. Our data demonstrated that GO and GO-PEG negatively affect heart contractility in frogs, inducing stronger arrhythmic contractions. They increased ROS production in C2C12 myoblasts, whose effects diminished after NIR irradiation. Both nanoparticles in the rat liver significantly stimulated DAO activity, with amplification of this effect after NIR irradiation. GO did not uncouple intact rat liver mitochondria but caused a concentration-dependent decline in ATPase activity in freeze/thaw mitochondria. This multifaceted investigation provides crucial insights into GOs potential for diverse implications in biological systems.

Circular value creation through environmental entrepreneurship initiatives: A case‐based exploration

AbstractThe present study builds on the domain of circular economy and its subdomain circular value creation to explore the entrepreneurial process of a small business in India. It aims to find how circular entrepreneurship as a process may unfold and how it may lead to value creation at different levels. The case study method is used to address the research objectives and a case study of a small entrepreneur based in India is selected for the same purpose. The analysis of the case and within case patterns (three subcases) illustrates circular entrepreneurship as a process with motivation, action and value creation as three main stages. The motivation of the entrepreneur leads to several actions related to business processes that are aimed at circular value creation. Subsequently, this leads to value creation at multiple levels such as the economy, business and society. Hence, the findings support the circular economy concept and its role in the creation of value at the small business level. The findings support the theoretical tenets of circular value creation and circular entrepreneurship using an interpretive approach.

Enhancing LiDAR performance using threshold photon-number-resolving detection.

Single-photon light detection and ranging (LiDAR) is widely used to reconstruct 3D scenes. Nevertheless, depth and reflectivity maps obtained by single-photon detection usually suffer from noise problems. Threshold LiDAR techniques using photon-number-resolving detectors were proposed to suppress noise by filtering low photon numbers, but these techniques renounce multiple levels of information and could not be compatible when it comes to high-noise low-signal regime. In this manuscript, we propose a detection scheme which combines the noise suppression of threshold detection with the signal amplification of photon-number-resolving detectors to further enhance LiDAR performance. The enhancement attained is compared to single-photon and threshold detection schemes under a wide range of signal and noise conditions, in terms of signal-to-noise-ratio (SNR), detection rate and false alarm rate, which are key metrics for LiDAR. Extensive simulations and real-world experiments show that the proposed scheme can reconstruct better depth and reflectivity maps. These results enable the development of high-efficient and low-noise LiDAR systems.

Nociplastic Pain and Pain-Motivated Drinking in Alcohol Use Disorder

Heavy chronic alcohol use may produce pain amplification through neurochemical and neuroplastic changes at multiple levels of the nervous system. Similar changes are thought to underlie nociplastic pain. The American College of Rheumatology Fibromyalgia Survey has been used as a surrogate for nociplastic pain, including among individuals with alcohol use disorder (AUD). However, studies linking nociplastic pain to pain-motivated drinking are lacking. The present study aimed to determine if nociplastic pain is associated with pain-motivated drinking in AUD. To achieve this aim, a new scale—the Pain-Motivated Drinking Scale (PMDS)—was developed to measure how often participants were motivated by pain to drink alcohol. Measurement properties of this new scale were determined, including its factor structure, internal consistency reliability, and construct validity. In this cross-sectional observational study, participants with AUD (n = 138) were consecutively recruited from the patient pool at an academic addiction treatment facility. Seventy-two percent (95, 72.0%) reported they drank alcohol “to get relief from physical pain” at least some of the time, and over forty-two percent (56, 42.4%) reported pain relief motivated their drinking at least half of the time. PMDS had a single-factor structure, strong internal consistency reliability, and construct validity. A multiple hierarchical linear regression was run to determine if nociplastic pain was associated with pain-motivated drinking. Nociplastic pain was associated with PMDS even after controlling for potential confounders and pain severity. These findings suggest nociplastic pain is uniquely associated with pain-motivated drinking in AUD. PerspectiveNociplastic pain is independently associated with pain-motivated drinking in alcohol use disorder (AUD). The Pain-Motivated Drinking Scale (PMDS) is a new scale to measure how often people drink to cope with pain. PMDS has promising psychometric properties. Nociplastic pain may be uniquely associated with pain-motivated drinking in AUD.

N-acetyltransferase NAT10 controls cell fates via connecting mRNA cytidine acetylation to chromatin signaling.

Cell fate transition involves dynamic changes of gene regulatory network and chromatin landscape, requiring multiple levels of regulation, yet the cross-talk between epitranscriptomic modification and chromatin signaling remains largely unknown. Here, we uncover that suppression of N-acetyltransferase 10 (NAT10), the writer for mRNA N4-acetylcytidine (ac4C) modification, can notably affect human embryonic stem cell (hESC) lineage differentiation and pluripotent reprogramming. With integrative analysis, we identify that NAT10-mediated ac4C modification regulates the protein levels of a subset of its targets, which are strongly enriched for fate-instructive chromatin regulators, and among them, histone chaperone ANP32B is experimentally verified and functionally relevant. Furthermore, NAT10-ac4C-ANP32B axis can modulate the chromatin landscape of their downstream genes (e.g., key regulators of Wnt and TGFβ pathways). Collectively, we show that NAT10 is an essential regulator of cellular plasticity, and its catalyzed mRNA cytidine acetylation represents a critical layer of epitranscriptomic modulation and uncover a previously unrecognized, direct cross-talk between epitranscriptomic modification and chromatin signaling during cell fate transitions.

Regulating antimicrobial use within hospitals: A qualitative study

To examine how regulatory structures and processes focused on antimicrobial stewardship and antimicrobial resistance are experienced by hospital managers and clinicians. Forty-two hospital managers and clinicians working within accreditation and antimicrobial stewardship teams in three Australian hospitals participated in individual in-depth interviews. Thematic analysis was performed. Thematic analysis revealed participants' experiences of hospital antimicrobial regulation and their perceptions of what would be required for meaningful antimicrobial optimisation. Theme 1: Experience of regulation of antimicrobials within hospitals: Participants described an increased profile of antimicrobial resistance with inclusion in regulatory requirements, but also the risks of bureaucratic manoeuvring to meet standards rather than governance-inducing systemic changes. Theme 2: Growth of accreditation processes and hospitals over time: Both regulatory requirements and hospitals were described as evolving over time, each manoeuvring in response to each other (e.g. development of short notice accreditation). Theme 3: Perceived requirements for change: Participants perceived a need for top-down buy-in, resource prioritisation, complex understanding of power and influence on clinician behaviour, and a critical need for medical engagement. This study around antimicrobials shows the tension and dynamic relationship between regulatory processes and hospital responses, bringing to light the enduring balance of a system that positions itself to meet regulatory requirements and emerging "demands", without necessarily addressing the key underlying concerns. Antimicrobial resistance-related solutions are perceived as likely to require further resourcing and buy-in across multiple levels, engagement across professional streams and require strategies that consider complex systems change in order for regulatory structures to have potency.