Coherent Group Research Articles

Charting the course of ferroptosis research in lung cancer: Insights from a bibliometric analysis

BackgroundLung cancer, a major cause of cancer-related mortality globally, necessitates innovative therapeutic strategies. Ferroptosis, an iron-dependent, non-apoptotic cell death form, has risen as a crucial therapeutic target. This study aims to conduct a comprehensive bibliometric analysis of ferroptosis in lung cancer, highlighting principal research trends, influential publications, and prospective future directions. MethodsThis study utilized bibliometric tools such as VOSviewer, CiteSpace, and the R package “bibliometrix” to thoroughly analyze 488 articles on ferroptosis in lung cancer from 2014 to October 2023. Data from the Web of Science Core Collection were analyzed to determine spatial and temporal trends, identify prominent authors and seminal works, and uncover emerging hotspots and frontiers of the field. The literature was segmented into coherent thematic groups through cluster analysis. ResultsOur analysis revealed a significant exponential growth in publications from 2019 to 2023, mirroring the increasing interest in this area. Predominantly, the influential research was published in high-impact journals, with Scott J. Dixon's works being the most cited. The study identified four primary research themes: Lung Cancer Specifics; Biomarker Identification and Prognosis; Cellular Death Mechanisms and Metabolic Regulation; and Cancer Stem Cells and Therapeutic Resistance. Recent studies have increasingly focused on areas such as the immune microenvironment and mitochondrial dysfunction. Furthermore, the analysis highlighted the field's global collaborative nature, with significant contributions from China, the USA, and Germany. ConclusionThis extensive bibliometric analysis emphasizes the growing importance of ferroptosis in lung cancer research. The identified themes and emerging topics underline the field's complexity and suggest new research avenues. This study promotes a holistic research approach, advocating for the exploration of innovative ferroptosis-targeting therapies that could revolutionize lung cancer treatment.

A Predictive Out-of-Step Identification Method Based on Wide-Area Velocity-Acceleration Trajectory

Online identification of the transient instability is essential in power system analysis, as it facilitates the grid operator to decide and coordinate system failure correction control actions. The rapid technological development of phasor measurement units (PMUs) provides an opportunity for online transient out-of-step identification in real-time. This paper analyzes the characteristics of angular velocity-acceleration trajectories in detail, and then proposes a predictive transient out-of-step identification method among coherent groups of generators based on the velocity-acceleration trajectory sampled by PMUs. To prove that the method can distinguish the transient out-of-step event following disturbance reliably, a mathematical proof of the criterion extended to multi-machine system is made, and the influences of the exciter and emergency control are taken into consideration to a certain extent. Finally, the effectiveness and predictability of the proposed method are demonstrated on a 39-bus New England test system and two large-scale power system simulation models of China by numerical studies.

Bronze Art, Cultural Norms, and Group Identity: A Group of Late Western Zhou and Early Spring and Autumn He Vessels Analyzed in Their Temporal and Spatial Contexts

abstract: A new generation of scholars has called into question the homogeneous nature of Western Zhou culture and the sweeping imposition of this culture over a large region that covers much of present-day China. Our study contributes to this debate by focusing on a coherent group of bronze vessels dated to the end of the Western Zhou and beginning of the Spring and Autumn periods. He (盉) vessels with drum-shaped bodies, bird-like lids, and human-like legs are among the most unique and artistically innovative artifacts of this period. While these unique artifacts have been found in and near the center of the Western Zhou polity, they are not associated with the rituals of the royal house, but rather with those of other aristocratic lineages. We argue that the artistic style of the vessels was part of the culture developed around the royal Zhou house and in areas close to it, although it is not strictly representative of the royal culture of the Western Zhou, being instead associated with minor lineages. A multi-dimensional analysis of this group of vessels, addressing their geographical distribution, location within their archaeological context, and social associations, combined with an analysis of their decorative scheme and the inscriptions cast inside them, enables us to better understand the sociocultural landscape of this period. Our study suggests that diversity existed not only in remote border areas or among the lower strata of society, but also within the cultural core of the Western Zhou polity and among the highest echelons of the aristocracy. Such processes of diversification are associated with the development of local and regional identities and with the growth of the political independence of aristocratic lineages during the final years of the transition from the Western Zhou to the Spring and Autumn periods.

Metamorphosis. A Portrait of a man holding gloves by the Master of the 1540s

This Portrait of a man by the Master of the 1540s has known a remarkable history, both in terms of ownership and especially in its change of outlook, hence the title Metamorphosis. Since 1907 it has been part of a stylistically coherent group of portraits, given by Max J. Friedländer to the so-called Master of the 1540s in 1936. In this article I have tried to give a full account of the picture’s provenance history, the various restorations it underwent and the changes in its outlook which were the result of these restorations, making use of historical photographs as well as modern methods of examination, including infrared reflectography (IRR), X-radiography and Macro X-ray Fluorescence (MA-XRF). In addition the portrait is used as a tool to understand more of the artist’s working methods, including the possible use of detailed portrait drawings, a tool that must have been used by most active portrait painters at the time, although only drawings (and connected portrait paintings) by Hans Holbein the Younger and Jean Clouet have survived in such numbers that something useful can be said on the functions of both drawing and underdrawing. Finally, I have proposed an identification of the artist in question as Cornelis van Cleve, who was born in 1520 as the only son of Joos van Cleve. Together with Willem Key, Cornelis was probably trained in his father’s studio as a portrait painter. After his father passed away in 1540-41, the young Cornelis took over his father’s thriving studio.

The Redox Stress Test: A novel technique reveals oxidative stress in Parkinson’s disease

A novel Redox Stress Test has been developed to identify symptoms of diseases associated with oxidative stress by observing symptom changes induced by short-term activation of the transcription factor Nrf2, to restore redox homeostasis. The Nrf2 pathway is triggered by a herbal preparation, Broccoli Seed Tea, developed to deliver a therapeutic dose of highly bioavailable sulforaphane, a potent activator of Nrf2. We discuss the rationale behind the tea and describe the methods used to optimise the bioavailability of sulforaphane to match the pharmacodynamics of Nrf2 activation. When consumed by people with Parkinson’s disease, the Redox Stress Test induced powerful and concurrent attenuation of a diverse group of Parkinson’s non-motor symptoms, including fatigue, constipation and urinary urgency. Motor symptoms were strictly unaffected. This observation indicates that oxidative stress may be a common factor contributing to non-motor symptoms involving sites in the CNS and peripheral organs. We tentatively interpret the results in terms of a hypothetical model for Parkinson’s Syndrome which we describe as a multisystem redox disorder with reservoirs of the disease in peripheral organs as well as in the brain. Eliminating the disease in peripheral organs is therefore a prerequisite to stopping disease progression in the brain. According to this model, the redox disorder in the brain provokes progressive neurological damage, which is not recognised as such in the early years. More specific neurological symptoms only come to light many years later, when damage to dopaminergic neurons creates a dopamine deficiency which eventually exceeds the threshold required for normal motor control, generating a new coherent group of neurological symptoms which define movement disorder. Given the apparent ease with which oxidative stress can be quenched in several locations simultaneously, we briefly discuss possible implications for public health, medical research, patients and patient advocacy groups. We note that the Redox Stress Test may have the potential to explore symptoms of other diseases where oxidative stress is believed to play a major role, although this remains subject to validation by further research.

CURRENT TRENDS OF MILITARY OUTSOURCING DEVELOPMENT: INSTITUTIONAL AND ECONOMIC ASPECTS

Defence outsourcing is a complex and controversial issue that arises for a variety of reasons, including a lack of military resources, the need for specialised expertise, and the desire to reduce political influence and risks. However, today the practice of military outsourcing raises many questions about security, regulation, control, ethics, accountability and transparency. This requires deeper research into the economics of military outsourcing in terms of adopting its development as a strategic goal.
 The purpose of the study is to summarise the theoretical and methodological basis and deepen the conceptual foundations of the military outsourcing economy, to substantiate the determinants of the formation of an effective institutional environment for the military outsourcing market, based on the analysis of global trends and national practices. The research methodology is based on systematic, comparative and economic analysis. It has been determined that the methodological basis of the outsourcing concept is the theory of the firm and contractual relations, transaction cost economics, public choice and organisational economics, the historical evolutionary combination of which has influenced the formation of approaches to the implementation of outsourcing as a component of the management model. The high efficiency of implementation of the outsourcing concept in commercial companies has led to its penetration into the armed forces and has led to the development of military outsourcing, the purpose of which is to optimise national military budgets on the basis of maximising economic, military, social and political effects. The generalisation of theoretical and methodological foundations allowed the author to substantiate the principles and build a composite structure of the concept of military outsourcing, as well as to identify coherent groups of objects and subjects of participation.
 An assessment of the current world practice of military outsourcing has made it possible to identify segmental trends in its development in the context of the urgent need to optimise national military budgets and to conclude that the pragmatic incentive is, on the one hand, the dilemma of growing military budgets and the importance of their optimisation, and, on the other hand, the urgent need to reduce costs. The author proves that military outsourcing is of great importance in the system of performing security functions of the State. A comparative analysis, identifying the advantages and disadvantages of the concepts of military outsourcing implemented by countries around the world, has revealed the dependence of their success on the quality of the institutional environment and substantiated the feasibility of applying a situation-based approach to its formation. According to this approach, the structuring of tasks assigned to the national armed forces should be implemented based on the principles of security priority and efficiency. The application of this approach makes it possible to increase the efficiency of military (combat) tasks without significantly reducing the degree of success in achieving the planned result, since the balance between the use of outsourcing and state self-sufficiency in this case is derived from adaptation to the current security situation. Proposals for building an operational framework for an effective institutional environment for military outsourcing in Ukraine are presented, outlining the main determinants, based on the analysis of global trends and national practices. It is noted that its formation should include: justification of the set of military and security functions that should be outsourced to private companies; description of the mechanisms of state control over the activities of private military companies and organisation of state response to cases of violations of human rights and/or humanitarian law.

Dependence of star formation rate on different properties of molecular clouds

Properties of molecular clouds (MCs) lying in our Galaxy and their star formation scenarios have been investigated with the help of multivariate unsupervised machine learning techniques concerning several observable parameters. At first, the MCs have been classified into four coherent groups using the standard K-means clustering method. Subsequently, the optimum number of groups has been estimated by applying the Elbow method as well as the computation of Silhouette widths for a robustness check. Later, the properties of the groups are studied through several observable parameters as mentioned along with computed ones e.g. star formation rates (SFRs), virial masses, mass-spectra, dynamical time scales (Td), etc. to get a deeper understanding of the star formation process and dynamical evolution of these clouds. It is found that cluster 1 is suitable for the formation of field stars, binary pairs, or stellar associations, whereas the clouds in cluster 2 and cluster 3 are favorable sites for the formation of Galactic clusters of moderate masses, and cluster 4 may produce massive Galactic clusters as well as a few globular clusters. Surprisingly, for each cluster, clouds at around Galacto-centric radius ∼8 kpc, and on the near Galactic plane has a significantly low SFR. These occurrences indicate that the star formation phenomenon has yet not started or the proneness to start in that region.

Discover, Explain, Improve: An Automatic Slice Detection Benchmark for Natural Language Processing

Abstract Pretrained natural language processing (NLP) models have achieved high overall performance, but they still make systematic errors. Instead of manual error analysis, research on slice detection models (SDMs), which automatically identify underperforming groups of datapoints, has caught escalated attention in Computer Vision for both understanding model behaviors and providing insights for future model training and designing. However, little research on SDMs and quantitative evaluation of their effectiveness have been conducted on NLP tasks. Our paper fills the gap by proposing a benchmark named “Discover, Explain, Improve (DEIm)” for classification NLP tasks along with a new SDM Edisa. Edisa discovers coherent and underperforming groups of datapoints; DEIm then unites them under human-understandable concepts and provides comprehensive evaluation tasks and corresponding quantitative metrics. The evaluation in DEIm shows that Edisa can accurately select error-prone datapoints with informative semantic features that summarize error patterns. Detecting difficult datapoints directly boosts model performance without tuning any original model parameters, showing that discovered slices are actionable for users.1

Bronze Art, Cultural Norms, and Group Identity: A Group of Late Western Zhou and Early Spring and Autumn He Vessels Analyzed in Their Temporal and Spatial Contexts

A new generation of scholars has called into question the homogeneous nature of Western Zhou culture and the sweeping imposition of this culture over a large region that covers much of present-day China. Our study contributes to this debate by focusing on a coherent group of bronze vessels dated to the end of the Western Zhou and beginning of the Spring and Autumn periods. He (盉) vessels with drum-shaped bodies, bird-like lids, and human-like legs are among the most unique and artistically innovative artifacts of this period. While these unique artifacts have been found in and near the center of the Western Zhou polity, they are not associated with the rituals of the royal house, but rather with those of other aristocratic lineages. We argue that the artistic style of the vessels was part of the culture developed around the royal Zhou house and in areas close to it, although it is not strictly representative of the royal culture of the Western Zhou, being instead associated with minor lineages. A multi-dimensional analysis of this group of vessels, addressing their geographical distribution, location within their archaeological context, and social associations, combined with an analysis of their decorative scheme and the inscriptions cast inside them, enables us to better understand the socio-cultural landscape of this period. Our study suggests that diversity existed not only in remote border areas or among the lower strata of society, but also within the cultural core of the Western Zhou polity and among the highest echelons of the aristocracy. Such processes of diversification are associated with the development of local and regional identities and with the growth of the political independence of aristocratic lineages during the final years of the transition from the Western Zhou to the Spring and Autumn periods. KEYWORDS: homogeneous culture, ritual and identity, bronze art, he vessels, winged animal and human figurines, Western Zhou and Spring and Autumn periods

Profiles of tobacco smokers and ex-smokers in a large-scale random sample survey across Wales: an unsupervised machine-learning cluster analysis

BackgroundThe Welsh government recently set a target to be smoke-free by 2030, which means reducing the prevalence of tobacco smoking in adults to 5% by then. The goal is to improve health and population life expectancy. To support this strategy, we identified profile groups with different sets of socioeconomic and demographic characteristics within the population of smokers. We compared these profiles to those identified in the ex-smoker population to provide a broader understanding of smokers and inform targeting of interventions and policy. MethodsWe did a cross-sectional study using data from the National Survey for Wales. This survey is a random sample telephone survey of individuals aged 16 years and older across Wales carried out from Sept 1, 2021 to Jan 31, 2022, weighted to be representative of the Welsh population. For the smoking subgroup, we did a weighted hierarchical cluster analysis with multiple imputation to impute missing data and repeated it for ex-smokers. In total, 63 survey variables were used in the analysis. These variables included smoking history, e-cigarette use, sociodemographics, lifestyle factors, individual-level deprivation, general health and long-term conditions, mental health, and wellbeing. FindingsAmong the 6407 respondents (weighted proportions: 49% male, 51% female; 28% aged 16–34 years, 46% aged 35–44 years, 26% aged ≥65 years; 95% white, 5% other ethnicity), 841 (13%) smoked and 2136 (33%) were ex-smokers. Four distinctive profiles of smokers were identified, the groups were of relatively comparable size and characterised by similarities described as (1) high-risk alcohol drinkers and without children; (2) single, mostly in social housing, and poor health and mental health; (3) mostly single, younger, tried e-cigarettes, and poor mental health; (4) older couples and poor health; when comparing the groups with each other. Cluster quality and validation statistics were considered fair: silhouette coefficient=0·09, Dunn index (Dunn2)=1·06. Generally, ex-smoker clusters differed from smoking clusters because of themes related to increased sickness, better affluence, employment, and older age (≥75 years). InterpretationThis study suggests that not all smokers are the same, and they do not fall into one coherent group. Smoking cessation interventions to improve the health of ageing populations might need a different approach to consider a wider context or motivations to inform targeted quitting. It is acknowledged that smoking might be underreported because of perceived social unacceptability. FundingPublic Health Wales.

The two-stage molecular scenery of SARS-CoV-2 infection with implications to disease severity: An in-silico quest.

The two-stage molecular profile of the progression of SARS-CoV-2 (SCOV2) infection is explored in terms of five key biological/clinical questions: (a) does SCOV2 exhibits a two-stage infection profile? (b) SARS-CoV-1 (SCOV1) vs. SCOV2: do they differ? (c) does and how SCOV2 differs from Influenza/INFL infection? (d) does low viral-load and (e) does COVID-19 early host response relate to the two-stage SCOV2 infection profile? We provide positive answers to the above questions by analyzing the time-series gene-expression profiles of preserved cell-lines infected with SCOV1/2 or, the gene-expression profiles of infected individuals with different viral-loads levels and different host-response phenotypes. Our analytical methodology follows an in-silico quest organized around an elaborate multi-step analysis pipeline including: (a) utilization of fifteen gene-expression datasets from NCBI's gene expression omnibus/GEO repository; (b) thorough designation of SCOV1/2 and INFL progression stages and COVID-19 phenotypes; (c) identification of differentially expressed genes (DEGs) and enriched biological processes and pathways that contrast and differentiate between different infection stages and phenotypes; (d) employment of a graph-based clustering process for the induction of coherent groups of networked genes as the representative core molecular fingerprints that characterize the different SCOV2 progression stages and the different COVID-19 phenotypes. In addition, relying on a sensibly selected set of induced fingerprint genes and following a Machine Learning approach, we devised and assessed the performance of different classifier models for the differentiation of acute respiratory illness/ARI caused by SCOV2 or other infections (diagnostic classifiers), as well as for the prediction of COVID-19 disease severity (prognostic classifiers), with quite encouraging results. The central finding of our experiments demonstrates the down-regulation of type-I interferon genes (IFN-1), interferon induced genes (ISGs) and fundamental innate immune and defense biological processes and molecular pathways during the early SCOV2 infection stages, with the inverse to hold during the later ones. It is highlighted that upregulation of these genes and pathways early after infection may prove beneficial in preventing subsequent uncontrolled hyperinflammatory and potentially lethal events. The basic aim of our study was to utilize in an intuitive, efficient and productive way the most relevant and state-of-the-art bioinformatics methods to reveal the core molecular mechanisms which govern the progression of SCOV2 infection and the different COVID-19 phenotypes.

Inflammatory Rhabdomyoblastic Tumor: Clinicopathologic and Molecular Analysis of 13 Cases

Inflammatory rhabdomyoblastic tumors (IRMTs) are newly recognized skeletal muscle tumors with uncertain malignant potential. We investigated 13 IRMTs using clinicopathologic, genetic, and epigenetic methods. The cohort included 7 men and 6 women, aged 23 to 80 years (median, 50 years), of whom 2 had neurofibromatosis type 1. Most tumors occurred in the deep soft tissues of the lower limbs, head/neck, trunk wall, and retroperitoneum/pelvis. Two tumors involved the hypopharyngeal submucosa as polypoid masses. Eight tumors showed conventional histology of predominantly spindled cells with nuclear atypia, low mitotic activity, and massive inflammatory infiltrates. Three tumors showed atypical histology, including uniform epithelioid or plump cells and mitotically active histiocytes. The remaining 2 tumors demonstrated malignant progression to rhabdomyosarcoma; one had additional IRMT histology and the other was a pure sarcoma. All 11 IRMTs without malignant progression exhibited indolent behavior at a median follow-up of 43 months. One of the 2 patients with IRMTs with malignant progression died of lung metastases. All IRMTs were positive for desmin and PAX7, whereas myogenin and MyoD1 were expressed in a subset of cases. Targeted next-generation sequencing identified pathogenic mutations in NF1 (5/8) and TP53 (4/8). All TP53 mutations co-occurred with NF1 mutations. TP53 variant allele frequency was much lower than that of NF1 in 2 cases. These tumors showed geographic (subclonal) strong p53 immunoreactivity, suggesting the secondary emergence of a TP53-mutant clone. DNA methylation–based copy number analysis conducted in 11 tumors revealed characteristic flat patterns with relative gains, including chromosomes 5, 18, 20, 21, and/or 22 in most cases. Widespread loss of heterozygosity with retained biparental copies of these chromosomes was confirmed in 4 tumors analyzed via allele-specific profiling. Based on unsupervised DNA methylation analysis, none of the 11 tumors tested clustered with existing reference entities but formed a coherent group, although its specificity warrants further study.

Severe arterial injury heals with a complex clonal structure involving a large fraction of surviving smooth muscle cells

Background and aimsSmooth muscle cell (SMC) lineage cells in atherosclerosis and flow cessation-induced neointima are oligoclonal, being recruited from a tiny fraction of medial SMCs that modulate and proliferate. The present study aimed to investigate the clonal structure of SMC lineage cells healing more severe arterial injury. MethodsArterial injury (wire, stretch, and partial ligation) was inflicted on the right carotid artery in mice with homozygous, SMC-restricted, stochastically recombining reporter transgenes that produced mosaic expression of 10 distinguishable fluorescent phenotypes for clonal tracking. Healed arteries and contra-lateral controls were analyzed after 3 weeks. Additional analysis of cell death and proliferation after injury was performed in wildtype mice. ResultsThe total number of SMC lineage cells in healed arteries was comparable to normal arteries but comprised significantly fewer fluorescent phenotypes. The population had a complex, intermixed, clonal structure. By statistical analysis of expected versus observed fractions of fluorescent phenotypes and visual inspection of coherent groups of same-colored cells, we concluded that >98% of SMC lineage cells in healed arteries belonged to a detectable clone, indicating that nearly all surviving SMCs after severe injury at some point undergo proliferation. This was consistent with serial observations in the first week after injury, which showed severe loss of medial cells followed by widespread proliferation. ConclusionsAfter severe arterial injury, many surviving SMCs proliferate to repair the media and form a neointima. This indicates that the fraction of medial SMCs that are mobilized to repair arteries increases with the level of injury.

STATCOM-Based Intelligent Wide-Area Controller for Damping Interarea Oscillation

This article presents an online scheme of static synchronous compensator (STATCOM)-based wide-area damping controller for interarea oscillation based on the oscillatory signals from a wide-area measuring system. For this purpose, by evaluating the rotor angles and speed deviations between coherent groups and providing them into the center-of-inertia frame, interarea signals are provided. For estimating controlling gains, using two classification and regression techniques (CART <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> and CART <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) as intelligent gain estimators, controlling gains <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">K</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">K</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> are estimated. In this case, each wide-area damping controller (WADC) consists of an intelligent STATCOM with global control signals for adjusting the line susceptance. The proposed classification and regression trees (CARTs) are trained offline in which by using interarea signal (IASs) through real-time evaluations, global controlling signals (GCGs) are estimated. It is an online nonmodel-based controller that estimates the STACOM susceptance based on the interarea oscillations. The effectiveness of the proposed STATCOM-based wide-area controller (SWADC) is evaluated on the New England 39-bus test system and practical Iran nation power grid with the potential of different interarea oscillation patterns. Results present the promising effects for damping the interarea oscillations.

Design of a decentralized wide-area control system to tolerate the loss of communication paths based on coherency analysis

The objective of this article is to design a wide-area control (WAC) system based on coherent groups of generators to overcome the loss of data and communication failures. In the conventional approach, the wide-area controller is designed by employing the state feedback control. It requires all the states on the controller input side and sending signals to all generators’ excitation systems on the output side. Therefore, good communication paths are necessary to get quality data every time. In addition, there should not be any data loss or false data due to phasor measurement units (PMUs) installed at every generator. However, it is not possible to get quality data without losing anything. Hence, it leads to the unstable condition of the entire power system. To address this problem, the area-wise coherency-based WAC system is proposed in this article to overcome the above-mentioned problems. The entire power system is divided into different areas based on coherency. Therefore, the centralized WAC system is divided into decentralized WAC systems based upon coherent groups of generators. This can be achieved by employing structurally constrained H2-norm optimization. Moreover, to validate the strength of the proposed controller, it is compared with different existing controllers reported in the literature by considering different case studies on IEEE-39 and IEEE-68 bus systems.

When Is Work Unjust? Confronting the Choice between ‘Pluralistic’ and ‘Unifying’ Approaches

ABSTRACTIndividuals have different experiences of work when they are self‐employed, when they perform tasks in the gig economy, and when they follow directives from managers. But such differences are not represented in some of the most prominent non‐ideal theories of work. These describe workers as a coherent group, with a position in the structure of the liberal capitalist economy. I present an alternative that does better at acknowledging difference, through a description of work and workers that has greater ‘pluralism’ and less ‘unifying coherence’. Some might insist that their ‘unifying’ description has superior empirical plausibility. But if ‘pluralistic’ descriptions are valid rivals to provide an accurate characterization of our current condition, then we should consider whether their use in theory can serve valuable aims. I identify the distinctive and valuable non‐ideal aims – epistemic, evaluative, and normative – that can be pursued with ‘pluralistic’ descriptions of work and workers.

Compositional clustering: Applications to multi-label object recognition and speaker identification

We consider a novel clustering task in which clusters can have compositional relationships, e.g., one cluster contains images of rectangles, one contains images of circles, and a third (compositional) cluster contains images with both objects. In contrast to hierarchical clustering in which a parent cluster represents the intersection of properties of the child clusters, our problem is about finding compositional clusters that represent the union of the properties of the constituent clusters. This task is motivated by recently developed few-shot learning and embedding models (Alfassy et al., 2019; Li et al., 2021) that can distinguish the label sets, not just the individual labels, assigned to the examples. We propose three new algorithms – Compositional Affinity Propagation (CAP), Compositional k-means (CKM), and Greedy Compositional Reassignment (GCR) – that can partition examples into coherent groups and infer the compositional structure among them. We show promising results, compared to popular algorithms such as Gaussian mixtures, Fuzzy c-means, and Agglomerative Clustering, on the OmniGlot and LibriSpeech datasets. Our work has applications to open-world multi-label object recognition and speaker identification & diarization with simultaneous speech from multiple speakers.

Segmentation of interconnected power systems considering microgrids and the uncertainty of renewable energy sources

AbstractThis paper proposes an approach for segmentation of power systems to prevent uncontrolled islanding. With the development of microgrids (MGs) and increased penetration of renewable energy sources (RESs) in the power system, it is necessary to consider the effect of MGs and the stochastic behaviour of RESs in the controlled islanding process. First, the enormous search space for finding the boundary points is reduced by the clustering of the coherent generators and the buses which are placed in sections that cannot be separated from the coherent groups. Then, linear AC power flow is defined as a sub‐problem and solved by linear programming to satisfy the power system and MG constraints. In this step, an optimization model is defined, and a mixed‐integer linear programming (MILP)‐based model is suggested to find cut‐sets and islands arrangement with reduced load shedding. In view of the fact that the fluctuation of RESs may have the significant effects on the power imbalance, to cover the uncertainties a scenario based stochastic simulation is considered. Finally, the effect of uncertainties on cut‐sets and load curtailment is evaluated. The effectiveness of the proposed methodology is demonstrated by the simulation on the test system.

High-mountain phylogeography in the Balkan Peninsula: isolation pattern in a species of alpine siliceous grasslands and its possible background

Although the Balkan Peninsula belongs to the most mountainous regions of Europe, phylogeographic structure of its alpine flora remains insufficiently understood, especially for species distributed both in the western and eastern parts of the Peninsula. We analyzed Campanula orbelica, a Balkan endemic typical of high-mountain siliceous grasslands, based on the population genetic structure, climatic niche modeling at the species- and intraspecific level, and niche hindcasting back to the Last Glacial Maximum (LGM; 20 kya). Our data reveal a clear phylogeographic pattern with three geographically coherent genetic groups: (i) the most divergent and spatially restricted lineage of the Pirin mountains (east), (ii) neighboring Rila mountains and other eastern Balkan massifs (Rhodopes, Stara Planina, Vitoša), and (iii) the most geographically disjunct mountains of the Scardo-Pindhic range (Šar Planina and Korab) in the west. This pattern indicates multiple refugia and isolated evolutionary centers within the Balkan Peninsula mountains, with the eastern part of the range as likely ancestral area, and an early dispersion into the western region, which formed the main geographical disjunction. The genetic divergence was only partly correlated with geographical isolation, clear dispersal barriers, or climatic niche shifts, suggesting contrasting isolation/dispersal dynamics in various parts of the range. Climatic niche overlap was low among eastern vs. western groups, which correlates with the longest spatial distance and significant genetic divergence, while niche characteristic of the Pirin lineage was a subset of the adjacent Rila lineage niche. High genetic divergence of the Pirin populations was also not correlated with persistent gaps in potential distributions but hypothetically may have been triggered by diversified (limestone/silicate) bedrock conditions. Our results highlight the need for high-mountain phylogeographic surveys in the eastern part of the Balkan Peninsula, to assess the biogeographical relevance of isolation patterns and definition of evolutionarily important units in the high-mountain flora.

Intentional Controlled Islanding Strategy for Wind Power Plant Integrated Systems

The concept of intentional controlled islanding (ICI) is introduced as a proactive measure to safeguard the power system against blackouts in the event of significant disturbances. It involves strategically partitioning the system into self-healing islands, thereby mitigating the impact of such disturbances. This study introduces a new framework for creating stable, controlled islands in power systems with large-scale wind power plants. The proposed islanding strategy takes into account the impact of wind power plants on the coherency grouping of generators as a constraint in the ICI problem. The proposed algorithm employs the Virtual Synchronous Motion Equation (VSME) model of asynchronous generators to replace wind power plants in power systems and groups all generators, including synchronous generators and wind turbine generators, based on their dynamic coupling. Support Vector Clustering is employed in the ICI problem to determine the coherent generator clusters as the cores of the formed islands. The algorithm can identify the optimal number of islands without prior information about the number of clusters. In this study, a Mixed Integer Linear Programming (MILP) model is formulated to address the ICI problem with the objective of minimising the power imbalance in each island after splitting while ensuring the transient stability and dynamic frequency stability of ICI. Simulation results on modified 39-bus and 118-bus test power systems demonstrate that integrating a Virtual Inertia Controller into the wind-integrated power systems results in a high-inertia power system that behaves similarly to a conventional power system with only synchronous generators during the islanding procedure.