bluuebunny/crossref_metadata_2025 huggingface dataset:
Ανθρωποκεντρικές τεχνικές υπολογιστικής όρασης για αυτόνομα συστήματα
Authors: Κακαλέτσης Ευστράτιος
Published: July 2024

Στόχος της παρούσας διδακτορικής διατριβής ήταν η ανάπτυξη και μελέτη τεχνικών υπολογιστικής όρασης και μηχανικής μάθησης που αφορούν στην ανάλυση εικόνων και εικονοσειρών που απεικονίζουν ανθρώπους (μεμονωμένους ή σε πλήθη). Οι τεχνικές αυτές, με την εξαίρεση μιας τεχνικής που αφορά στην διάδοση ετικετών ταυτότητας ατόμου σε εικόνες προσώπου, έχουν σαν στόχο να επικουρήσουν στην λειτουργία και την πλοήγηση αυτόνομων συστημάτων (ρομπότ, μη επανδρωμένα αεροχήματα, UAVs) ή εμπλέκουν τέτοια συστήματα για την αποτελεσματικότερη συλλογή δεδομένων (ενεργητική όραση). Το πρώτο κεφάλαιο καταπιάνεται με το θέμα της αναγνώρισης προσώπων και συγκεκριμένα με την επιτάχυνση και αύξηση της απόδοσης του (δημοσιευμένου στην βιβλιογραφία) αλγορίθμου διάδοσης ετικετών ταυτότητας ατόμου σε πολλαπλούς γράφους με βάση την ομαδοποίηση και τις προβολές που διατηρούν την τοπικότητα (Multiple-graph Locality Preserving Projections - Cluster-based Label Propagation, MLPP-CLP). Προτείνεται επίσης μια τεχνική επαυξητικής (incremental) διάδοσης ετικετών η οποία μπορεί να μειώσει την υπολογιστική πολυπλοκότητα της διάδοσης ετικετών σε εικόνες προσώπου όταν αυτή εφαρμόζεται σε δεδομένα των οποίων το πλήθος αυξάνεται με τον χρόνο. Στο δεύτερο κεφάλαιο παρέχεται μια επισκόπηση τεχνικών υπολογιστικής όρασης (π.χ. τεχνικών σημασιολογικής κατάτμησης εικόνας, χαρτογράφησης εξωτερικών χώρων για ανίχνευση τοποθεσίας προσγείωσης, σημασιολογικής χαρτογράφησης για ΣμηΕΑ και κινούμενα ρομπότ κλπ) που συμβάλλουν στην ασφάλεια πτήσεων, θέμα κρίσιμο για την πλοήγηση μη-επανδρωμένων αεροσκαφών. Δίνεται επίσης μια σύνοψη της σχετικής νομοθεσίας και κανονισμών ανά τον κόσμο. Οι τεχνικές αυτές είναι σχετικές με οποιοδήποτε είδος πτήσης αυτόνομων ΣμηΕΑ (π.χ., για την παραγωγή ταινιών/ τηλεόρασης, έρευνας/διάσωσης, επιθεώρησης, χαρτογράφησης, διαχείριση πλήθους) καθιστώντας το θέμα αυτό ευρέος ενδιαφέροντος. Στο τρίτο κεφάλαιο παρουσιάζονται εργαλεία που μπορούν να περιληφθούν σε αλγοριθμικές αλληλουχίες ασφάλειας πτήσεων των UAVs. Αρχικά, παρουσιάζεται μια τεχνική για τον εντοπισμό πιθανής τοποθεσίας προσγείωσης Μη Επανδρωμένων Αεροσκαφών (UAV) με χρήση πληροφοριών εδάφους μέσω αναγνώρισης επίπεδων περιοχών. Επίσης, προτείνεται μία μέθοδος αυτόματης επισημείωσης τρισδιάστατων χαρτών με περιοχές πλήθους, μέσω προβολής δισδιάστατων επισημειώσεων που προέρχονται από την οπτική ανάλυση βίντεο UAV. Στο τέταρτο κεφάλαιο παρουσιάζεται μια μέθοδος για εύρωστο, εν κινήσει 3D εντοπισμό και χαρτογράφηση πλήθους ανθρώπων σε μεγάλης κλίμακας εξωτερικά περιβάλλοντα. Η μέθοδος προϋποθέτει (και χρησιμοποιεί) την ανεξάρτητη οπτική ανίχνευση του πλήθους από αντίστοιχους ανιχνευτές στα βίντεο από τις κάμερες πολλαπλών ΣμηΕΑ. Το τελευταίο κεφάλαιο καταπιάνεται με ένα θέμα ενεργητικής υπολογιστικής όρασης που εμπλέκει ρομποτικά αυτόνομα συστήματα. Συγκεκριμένα, προσπαθώντας να αντιμετωπίσουμε την έλλειψη αλγορίθμων ενεργητικής αναγνώρισης προσώπου, σε αυτήν την Ενότητα, προτείνουμε μια προσέγγιση που χρησιμοποιεί φωτορεαλιστικές συνθετικές όψεις προσώπου που παράγονται από μία όψη.
A cure worse than the disease? The controversy on Twitter around a fake COVID-19 treatment from France
Authors: Smyrnaios Nikos , Tsimpoukis Panos , Papaevangelou Charis
Published: July 2024

This paper analyzes both the network of actors and the network of the discourses mobilized in the controversy around Professor Didier Raoult and his Hydroxychloroquine-based therapeutic proposal against COVID-19. To confirm our hypothesis, we implement a sophisticated and innovative research method on a corpus of 1.2 million Tweets, which consists of applying a network analysis combined with a lexicometrics analysis. We show that the reaction peaks on Twitter were linked to important media events. Moreover, many groups clustered around the accounts of political figures and media outlets that received numerous mentions. Trump's and Bolsonaro's supporter groups also connected with the French-speaking pro-Raoult groups. The messages of the pro-Raoult combined anti-science conspiracy theories and a critique of the political economy of liberalism and its impasses
Configuring, optimizing and enhancing Dataverse: The case of SoDaNet Repositories
Authors: Linardis Apostolos , Kondyli Dimitra , Alexandris Konstantinos , Papagiannopoulos Konstantinos , Nisiotis Konstantinos – Symeon , Mastoris Nikolaos , Klironomos Nicolas
Published: July 2024

Current trends in computational social sciences and data-driven research require access to reliable data sources. Data repositories fulfil this role, providing high-quality data services, since they satisfy certain requirements that can be briefly summarized as complying with the FAIR data principles. In this context, we outline the measures undertaken by SoDaNet to enhance the data repositories within our infrastructure. Through the adoption and implementation of the Dataverse software, along with a series of adaptations and customizations, we have improved the Findability, Accessibility, Interoperability, and Reusability (FAIR) of the data hosted in these repositories. This effort has resulted in data repositories responding effectively to the demands of the research community, improving the user experience both nationally and internationally.
Metaverse Framework Designing for Energy Scheduling in Energy Internet of Things Considering Emergence
Authors: HAN Yechen , He Xing , ZHANG Haihong , ZUO Yuanjun , ZHANG Wenjing , Ai Qian , CHEN Zhuo
Published: July 2024

The traditional scheduling approach, which primarily considers energy oligarchs like large-scale loads and large-scale generators, is challenged by the rapid rise of distributed energy resources (DERs) in energy internet of things (EIoT). Metaverse is emerging as one of the most promising technologies considering emergence from DERs in EIoT. Our work, from a macro perspective in the virtual space, provides a metaverse framework to harness the swarm intelligence that emerges from the aggregation behavior of massive diverse DERs in EIoT. The presented framework is built upon virtual twins, data science, systems theory, and 4th-Paradigm (data-intensive scientific discovery paradigm), enabling a novel energy scheduling mode. Our goal is to achieve data empowerment and intelligence improvement through data connectivity, virtual and real interaction, which will ultimately result in a new theory on complex system scheduling.
Clinical and pathological characteristics of blastoid mantle cell lymphoma: a single institution experience
Authors: Monappa Vidya , Prabhu Swathi , Kudva Ranjini , Godkhindi Vishwapriya Mahadev , Pai Kanthilatha , Pai Ananth , Mailankody Sharada
Published: July 2024

Background Blastoid mantle cell lymphoma (B-MCL) is a rare aggressive lymphoma. It is characterized by blastoid morphology with high proliferation and inconsistent immunohistochemistry (IHC), making it a diagnostic challenge for the pathologist. Methods This is a retrospective analytical cohort study. We reviewed biopsy confirmed cases of B-MCL diagnosed over a period of 10 years (January 2012 to December 2022). The clinical presentation, histopathological and IHC findings, treatment received, and survival outcomes were studied. Randomly selected cases of classic MCL (n=12), diagnosed during the same period served as controls. Results A total of 12 cases were studied. Four cases were transformed from previously diagnosed MCL; 8 cases arose de novo. Mean age was 61.17 years and the male: female ratio was 5:1. Half of the cases showed extra nodal extension and 81.8% had bone marrow involvement. Gastrointestinal tract was the most common site of extra nodal involvement. Histopathological examination showed diffuse involvement of the lymph node with medium sized cells. On immunohistochemistry, one of the cases showed loss of CD5 expression while the other had aberrant CD10 expression. Mean Ki-67 index was 58.09% in the cases and 16.33% in controls and was statistically significant (p=0.005). The median overall survival (OS) for cases was 2 years vs 8 years in controls. The p53 over expression (>30% nuclear positivity) was seen in 66.6% cases (4/6). Conclusion There are several factors that contribute to the aggressiveness of B-MCL, and new treatment approaches might be required to improve patient outcomes.
Analysis of the dynamics of transition from non-colonization to colonization and Staphylococcus aureus bacteremia in hemodialysis patients using Markov models.
Authors: Montoya-Urrego Daniela , Vanegas Johanna M , Jiménez J Natalia , González-Gómez Difariney
Published: July 2024

Background Hemodialysis patients are frequently colonized by Staphylococcus aureus, leading to severe infections with high mortality rates. However, little is known about transition from non-colonization to colonization or bacteremia over time. The aim was to analyze the behavior of S. aureus colonization, identifying the probability of transition from non-colonized to colonized state or bacteremia, and the influence of some covariates. Methods The study was conducted in a dialysis unit associated with a high complexity hospital in Medellín between October 2017 and October 2019. An initial measurement was taken to evaluate S. aureus colonization, and follow-up measurements were performed 2 and 6 months later. Bacteremia evolution was monitored for 12 months. A two-state recurrent continuous-time Markov model was constructed to model transition dynamics from non-colonization to S. aureus colonization in hemodialysis patients. Subsequently, the model was applied to a third state of bacteremia. Results Of 178 patients on hemodialysis, 30.3% were colonized by S. aureus. Transition intensity from non-colonization to colonization was three times higher (0.21; CI: 0.14-0.29) than from colonization to non-colonization (0.07; CI: 0.05-0.11). The colonization risk increased in patients with previous infections (HR: 2.28; CI: 0.78-6.68), hospitalization (HR: 1.29; CI: 0.56-2.99) and antibiotics consumption (HR: 1.17; CI: 0.53-2.58). Mean non-colonized state duration was 10.9 months, while in the colonized state was 5.2 months. In the 3-state model, it was found that patients colonized were more likely to develop S. aureus infection (13.9%). Conclusion A more likely transition from non-colonization to colonization was found, which increases with factors such as previous infection. In addition, the development of bacteremia was more likely in colonized than in non-colonized patients. These results underline the importance of surveillance and proper management of S. aureus colonization to prevent serious complications, such as bacteremia, and improve prognosis in this vulnerable population.
A scoping review of health models for the community mental health needs of the United Arab Emirates: Nurturing the social determinants of mental health through social prescribing in the Middle East
Authors: Mottershead Richard , AL-Fayyadh Sadeq , Al-Yateem Nabeel , Subu Muhammad Arsyad , Bani-Issa Wegdan , Taha Mohamed Hassan , Ahmed Fatma Refaat , Dias Jacqueline Maria , Adams Shukri , Wali Adil Farooq , Shahrour Ghada , Al Mutair Abbas , Murendo Conrad , Alonaizi Nafi , Alhaiti Ali , Alruwaili Majed Mowanes , Alruwaili Abeer Nuwayfi , McManus Jim
Published: July 2024

Despite the growing interest in social prescribing the diversification of health and social care strategies to support the well-being of patients has remained entrenched with a focus on the hospital setting within the Middle East. The United Arab Emirates has commenced progressing community mental health care to lead changes in how care and treatment are delivered within the United Arab Emirates. The authors adopted the use of the framework of Arksey and O’Malley (2005) to provide a systematic approach to searching the literature and creating a comprehensive foundation to guide the review. This scoping review provides a better understanding of the compatibility, content and outcomes of a selection of health models. The scoping review findings will inform the proposed use of social prescribing as an actionable approach to create a focus on the need to include and empower the social determinants of mental health. This article proposes an evidence-based health strategy that supports and enhances recent additions to national legislation on the inclusion of the Mental Health Law within the United Arab Emirates to meditate and prevent inequities in addressing the mental health needs of citizens and residents within the nation’s diverse communities.
The genome sequence of a braconid wasp, Aleiodes testaceus (Telenga, 1941)
Authors: Broad Gavin R. , Cunningham-Eurich Iona ,   Natural History Museum Genome Acquisition Lab,   Darwin Tree of Life Barcoding collective,   Wellcome Sanger Institute Tree of Life Management, Samples and Laboratory team,   Wellcome Sanger Institute Scientific Operations: Sequencing Operations,   Wellcome Sanger Institute Tree of Life Core Informatics team,   Tree of Life Core Informatics collective,   Darwin Tree of Life Consortium
Published: July 2024

We present a genome assembly from an individual female Aleiodes testaceus (braconid wasp; Arthropoda; Insecta; Hymenoptera; Braconidae). The genome sequence spans 110.70 megabases. Most of the assembly is scaffolded into 19 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 28.0 kilobases in length. Gene annotation of this assembly on Ensembl identified 10,520 protein-coding genes.
Bienestar Animal: políticas y sociedad.
Authors: Sánchez-Herrera Francisco
Published: July 2024

Los países europeos están reconociendo gradualmente los derechos de los animales e implementando políticas sociales específicas. Particularmente en España, el debate se intensifica con la aprobación de la ley 17/2021 sobre bienestar animal. Esta investigación busca analizar los principales argumentos sobre los animales como sujetos de derecho en nuestras sociedades. La metodología consiste en una revisión sistemática de la literatura especializada. Los resultados revelan cuatro ejes argumentativos. El primero se enfoca en políticas europeas y nacionales que desde la década de 1980 consideran a los animales como seres sintientes, vinculando su buen trato con las ayudas de la PAC. El segundo destaca los beneficios físicos y psicológicos de la relación humano-animal. Un tercer eje aborda la inclusión social de los animales por parte de partidos políticos socialdemócratas. Finalmente, un cuarto eje surge con la ampliación del concepto de ciudadanía a los animales, liderado por “Zoopolis” en 2011. Como principales conclusiones, el bienestar animal se vislumbra como un concepto revisable, que se aproxima hacia el de ciudadanía, en conexión y sinergia con el de bienestar social.
"Integración del marketing interno para optimizar la felicidad en el trabajo y reducir la intención de rotar en la era de la Industria 5.0": "Integration of internal marketing to optimise workplace happiness and reduce turnover intentions in the era of Industry 5.0".
Authors: Salazar-Altamirano Mario Alberto , Martínez-Arvizu Orlando Josué , Gómez Sánchez David
Published: July 2024

This study is set within the context of Industry 5.0, where organisations must balance economic objectives with sustainability, ethics, and justice, in accordance with the Sustainable Development Goals (SDGs). Using a non-experimental, cross-sectional quantitative approach, an online questionnaire was employed to collect data from 233 employees across various industries in Mexico. The findings indicate that internal marketing positively affects job happiness and reduces job stress, while job happiness decreases the intention to turnover. However, no significant direct relationship was found between internal marketing and turnover intention. Limitations include the cross-sectional design and geographically restricted sample, suggesting the need for longitudinal studies and more diverse samples. The study’s original contribution lies in demonstrating how internal marketing can optimise job happiness and, thereby, influence employee retention and stress reduction, providing a robust theoretical framework for future research in the era of Industry 5.0.
Posicionamiento de las operadoras de telefonía móvil en Venezuela después de la hiperinflación.
Authors: Baskin Roberto
Published: July 2024

El objetivo de este estudio fue lograr una aproximación empírica dirigida al posicionamiento mercadotécnico de las operadoras/marcas de telefonía móvil en Venezuela después de la etapa de hiperinflación que duró aproximadamente cuatro años (2017-2020). Fundamentalmente, se trabajó con datos de fuente primaría generados por un estudio ad hoc de metodología cuantitativa (técnica encuesta online). Resultó que los posicionamientos de las tres operadoras/marcas que funcionan en el país perceptualmente lucen lejos de la marca ideal. Años de desinversión en actualización tecnológica causaron significativos problemas de atención al cliente que se revirtieron negativamente en la imagen de todas las entidades. El mercado ofrece oportunidades para las operadoras que mejoren la prestación de servicio desde el punto de vista técnico (cobertura/conectividad y calidad) y se enfoquen en CX (customer experience).
The effect of influencer interactivity on customer brand engagement: An interactivity theory perspective: The effect of influencer interactivity on customer brand engagement: An interactivity theory perspective.
Authors: Ligaraba Neo , Mohammed Aqeelah , Mohamed Husnaa
Published: July 2024

TikTok has become highly popular among young consumers, offering a valuable platform for brands to partner with influencers. This paper investigates the effect of TikTok fashion influencer interactivity on brand and behavioural outcomes of young consumers. The quantitative data were collected from 233 TikTok fashion influencer followers, using convenience sampling technique. The relationships among variables were tested using structural equation modelling Smart PLS 4.0 and the Statistical Package for the Social Sciences version 28. The results indicate that influencer interactivity has a positive and significant effect on brand credibility. Furthermore, brand credibility significantly and positively influenced customer brand engagement. Customer brand engagement is found to be a significant mediate between brand image and purchase intention. Leveraging interactive influencers can enhance brand credibility, and as brand credibility increases, so will customer brand engagement, brand image and purchase intention. These findings can guide marketers to make informed decisions when choosing effective interactive influencers. This study provides a better understanding of the impact of influencer interactivity which will be helpful to marketers in developing an effective TikTok marketing strategy. This study contributes the influencer marketing literature by proposing a model to understand how influencer interactivity can influence behavioural outcomes.
Optimal Policies and Heuristics to Match Supply with Demand for Online Retailing
Authors: Deng Qiyuan , Li Xiaobo , Lim Yun Fong , Liu Fang
Published: July 2024

Problem definition: We consider an online retailer selling multiple products to different zones over a finite horizon with multiple periods. At the start of the horizon, the retailer orders the products from a single supplier and stores them at multiple warehouses. The retailer determines the products’ order quantities and their storage quantities at each warehouse subject to its capacity constraint. At the end of each period, after random demands in the period are realized, the retailer chooses the retrieval quantities from each warehouse to fulfill the demands of each zone. The objective is to maximize the retailer’s expected profit over the finite horizon. Methodology/results: For the single-zone case, we show that the multiperiod problem is equivalent to a single-period problem and the optimal retrieval decisions follow a greedy policy that retrieves products from the lowest-cost warehouse. We design a nongreedy algorithm to find the optimal storage policy, which preserves a nested property: Among all nonempty warehouses, a smaller-index warehouse contains all the products stored in a larger-index warehouse. We also analytically characterize the optimal ordering policy. The multizone case is unfortunately intractable analytically, and we propose an efficient heuristic to solve it, which involves a nontrivial hybrid of three approximations. This hybrid heuristic outperforms two conventional benchmarks by up to 22.5% and 3.5% in our numerical experiments with various horizon lengths, fulfillment frequencies, warehouse capacities, demand variations, and demand correlations. Managerial implications: A case study based on data from a major fashion online retailer in Asia confirms the superiority of the hybrid heuristic. With delicate optimization, the heuristic improves the average profit by up to 16% compared with a dedicated policy adopted by the retailer. The hybrid heuristic continues to outperform the benchmarks for larger networks with various structures.

Funding: X. Li is supported by the Singapore Ministry of Education [Tier 1 Grant 23-0619-P0001]. Y. F. Lim is grateful for the support from the Singapore Management University under the Maritime and Port Authority Research Fellowship and the Singapore Ministry of Education [Tier 1 Grant MSS23B001].

Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2021.0394 .
School-based indicated prevention interventions for anxiety in children and adolescents: A commentary on a systematic review
Authors: Harris Catherine , Packwood Dave , Wood Amy , Loughran Lynn , Wheeler Paula , Hill James Edward
Published: July 2024

Mental health problems such as anxiety are on the increase in children and adolescents. However, rising demand and cuts to mental health services make it difficult for young people to access the support they need. School-based interventions aimed at preventing or reducing anxiety have the potential to provide help to large numbers of children and adolescents. However, the effectiveness of these interventions for different groups is somewhat unclear. This commentary summarises and critically appraises a recent systematic review which investigated the effectiveness of school-based interventions to prevent and reduce anxiety symptoms in indicated groups of children and adolescents.
Anxiety in infancy: Implication for the teenage years
Authors: Thornton Stephanie
Published: July 2024

Anxiety in infancy and early childhood can be a predictor of mental health problems in adolescence and very early intervention may help mitigate these. Stephanie Thornton looks at the causes, diagnosis and management of anxiety in young children.
Purpose-Driven Involvement for College Students of Color
Authors: Luedke Courtney L. , Garcia Crystal E.
Published: July 2024

Abstract: Using data from a longitudinal study on a first-year program for college Students of Color, this study examines students’ purposeful engagement in extracurricular activities. We engage Bourdieu’s Social Reproduction Theory to understand how students’ existing capital and new forms of capital were acquired and nurtured through their student involvement. We explored what attracts students to organizational opportunities and what keeps them engaged in these organizations. Findings showed the importance of connections with other minoritized students in dominant spaces, organizational values and racial capital, and access to spaces that provided resources and professional development. Implications for research, practice, and theory are discussed.
Limits to Negotiated Accountability of Economic Accomplices: The Case of Volkswagen do Brasil
Authors: Bohoslavsky Juan Pablo , Goñi Juan Cruz
Published: July 2024

ABSTRACT: This article critically analyzes the agreement signed in 2020 between Volkswagen do Brasil and the Federal Prosecutor’s Office, which marked the closure of previous civil claims filed by a group of employees who were victims of gross violations of their human rights and alleged the complicity of the company during the dictatorship in Brazil. The conclusions challenge the triumphant story provided by both the State and the company itself and highlight the dark side of using negotiated agreements in the context of civil litigation as a way to achieving guarantees of justice, truth, memory, reparation, and non-repetition.
Sieyès’s Constitutional Jury, the Pennsylvania Council of Censors, and the Debate on the Conservative Power in the French Revolution
Authors: Brown Angus Harwood
Published: July 2024

Abstract: Emmanuel-Joseph Sieyès’s 1795 proposal for a Constitutional Jury is usually portrayed as the first proposal for an institution to control the constitutionality of laws, and thus the ancestor of the modern constitutional court. Challenging this view, this article resituates the Constitutional Jury in a broader transatlantic tradition concerned with creating a conservative power, a non-judicial and explicitly political constitutional guardian, and demonstrates the influence of the 1776 Pennsylvania Council of Censors on Sieyès’s Constitutional Jury. Drawing upon the insights provided by this tradition, it then reevaluates the history of constitutionalism and the contemporary crisis of constitutional guardianship.
The Analysis of Dyes in Textiles
Authors: Laursen Richard
Published: July 2024

Abstract: This article discusses the more useful instrumental methods for the analysis and identification of natural (non-synthetic) dyes in textiles, specifically so-called invasive methods that require removal of a sample from the textile or other object, and the non-invasive ones that do not. The invasive methods usually include a separation step, primarily using high-performance liquid chromatography and provide much more information about the dyes than do non-invasive ones. On the other hand, instrumentation for some non-invasive methods is significantly less expensive and gives fast results, without altering the object. A third category that can be called minimally invasive shares advantages and disadvantages of the previous two. Also discussed are the classes of dyestuffs used for dyeing different colors, along with specific examples, and how identification of them can give clues as to the site of production of the textile.
Arkilla , Kaasa , and Nsaa : The Many Influences of Wool Textiles from the Niger Bend in West Africa
Authors: Gardi Bernhard , Gilbert Michelle
Published: July 2024

Abstract: Wool from the Massina sheep was used to create a dozen or so kinds of textiles patterned by extra (supplementary) weft and tapestry weave in the Niger Bend region. This constellation makes the region the foremost center of technical and visual diversity in West African treadle-loom weaving traditions. Two major categories of wool textiles can be identified: kaasa and arkilla , both heavy covers of different sizes. Whereas the visual appearance of kaasas changed greatly over the twentieth century, that of the ceremonial marriage covers, arkilla, stayed the same. A third category, with wool ornamentation on a cotton ground, was woven in the northeastern part of Burkina Faso. The history of these woolen textiles is intimately linked to the social system of the Fulani people who own the sheep. Highly specialized male weavers called maabuuɓe, who form a kind of “caste,” made the kaasas and arkillas. The wool-cotton covers were made by weavers of enslaved status. The abolishment of slavery by the French in their West African territories in 1905 had profound consequences. A generation or more later, weaving traditions started to change in the Niger Bend: formerly enslaved weavers versed in traditional techniques started their own weaving businesses supported by women who bought industrial threads. New cover types came into being, with new combinations of colors and patterns, which were woven in the same techniques as with handspun wool. This is how extra-weft patterns and tapestry weave were slowly introduced to the huge region to the east, stretching from the eastern part of the Niger Bend to Lake Chad, and also how the rich Zarma weaving of the Republic of Niger came into being and Hausa weavers in Nigeria “discovered” tapestry weaving. Another, albeit much older, line of influence goes straight into Ewe weaving of Togo and Ghana. For several hundred years, these so-called wool covers were traded to the Akan kingdoms of southern Ghana and Côte d’Ivoire, 1000 kilometers to the south, where they were called nsaa : there, they were reused and attained great ritual significance. This article seeks to correlate loom and weaving technologies with terminology to better reveal this diffusion of pattern weaving throughout important parts of West Africa. As most weaving was originally done with cotton—but mostly without extra weft—the tradition of wool weaving might shed new light on ornamentation in other West African weaving traditions.
Reconstructing the Historic Akhnif : A Semi-Circular Woven-to-Shape Cloak of Southern Morocco
Authors: Naji Myriem
Published: July 2024

Abstract: This article gives a detailed account of akhnif making. An akhnif is a woven-to-shape semi-circular man’s black hooded cloak with a characteristic “eye” design, which was worn in southern Morocco until the 1950s. It combines insights gained from ethnographic fieldwork among the Ayt Waghrda mountain dwellers of the Sirwa in the High Atlas mountain range (2002–2003), the commissioning of an akhnif in 2003 that was filmed for over 30 hours, and the study of historic objects in European and Moroccan museums. By focusing on the loom and specific weaving and finishing techniques, the article considers how this garment is closely related to others in North Africa. It also contributes to the understanding of the wider history of the Mediterranean traditions of weaving clothes to shape.
An Amazon in Antinoë: Contextualizing a Late Antique Textile from Egypt
Authors: McDonald Malik Max
Published: July 2024

Abstract: The collection of late antique Egyptian objects housed in The George Washington University Museum and The Textile Museum’s Cotsen Textile Traces Study Center number in the hundreds, but not many have been the subject of in-depth art historical research. One such textile is a small square fragment, identified with its accession number, T-0690. Previous documentation within the museum’s collection database on T-0690 only includes past social media posts highlighting the artifact, one of which refers to its central figure as a male warrior while the other focuses on the weaver’s use of red-purple dye to color the figure’s Phrygian cap. A closer look at the fragment, woven sometime in the fifth or sixth century CE, reveals the central figure to be an Amazon, one of a race of female warriors thought by the ancient Greeks and Romans to inhabit the Scythian lands, roughly modern Russia and Central Asia. This emerging research note will attempt to place this late antique textile within its archaeological and art historical context through a brief discussion of the culture in which it was made, a reconstruction of its object biography, and a comparative study with other Greco-Roman artistic depictions of Amazons. When all of these aspects of its history are considered, it becomes clear that the weaver of this textile was broadly aware of the many ways in which the Amazons were portrayed in the art of previous ancient Mediterranean civilizations. He or she likely employed multiple visual characteristics, which normally do not coexist on a single piece, in order to give the figure unmistakably “Amazonian” traits.
Implementation of atomic layer deposited AZO films in SLM structures
Authors: Marinova Vera , Petrov Stefan , Chau Nguyen Hong Minh , Petrova Dimitrina , Napoleonov Blagovest , Videva Vladimira , Hsu Ken-Yuh , Dimitrov Dimitre , Lin Shiuan-Huei
Published: July 2024

Here, we demonstrate the implementation of transparent conductive aluminum-doped zinc oxide (AZO) thin films deposited on glass substrate (AZO/glass) by the atomic layer deposition technique in liquid crystal (LC) spatial light modulator (SLM) devices. Structural, optical, and electrical properties as well as surface free energy reveal the high quality and uniformity of deposited AZO layers. We present two types of structures that highlight the multifunctional role of AZO thin films in SLM configurations: (i) as a transparent conductive layer for assembling regular antiparallel LC cells and (ii) as a transparent conductive layer and alignment layer allowing vertical alignment in LC display devices. A comparison of the electro-optical parameters such as pre-tilt angle, phase modulation, driving voltage, and response time of both devices is presented and discussed. AZO thin films prove superior performance, indicating a growing demand for the next generation indium tin oxide-free technology, including advanced display devices and dynamic flat-panel functionalities.
Multi-plane imaging technology with constant imaging quality
Authors: Zhai Zhongsheng , Yu Xiatian , Zeng Zhen , Zhang Yi , Lv Qinghua , Liu Da , Tu Jun
Published: July 2024

To realize three-dimensional microscopic imaging with high time resolution and high space resolution at the same time, a multi-plane imaging method with constant axial multi-plane imaging quality is proposed. The optical theory to ensure that different axial sections have consistent lateral resolution has been analyzed. In the system, it is proposed to superimpose a spatial light modulator with programmable ability and wavefront control function on the focal plane of the image square of the front group of the infinite tube length microscope objective and load a digital multiplexing lens with multi-focus and multi-diffraction angle to form a new combined imaging system. The system can clearly image any axial section or multiple target planes within a certain imaging range without compensating the imaging aberration of the axial section, so that each axial section has the same imaging quality. With the help of the USAF 1951 resolution chart, it is verified that different axial object planes have consistent lateral resolution up to 57.0 lp/mm. For samples with different thicknesses, multi-plane layer-by-layer imaging and multi-plane simultaneous imaging experiments were performed using single-focus lens, multi-focus Fresnel lens, and digital multiplexing lens phase grayscale images, respectively. Experimental results show that this scheme can achieve some degree of simultaneous multiplanar imaging with an axial spacing of up to 0.2 mm, which is potentially useful in research areas where samples should not be moved or where relative motion is not desirable.
Non-selective reflection broadening of a cholesteric liquid crystal at oblique incidence
Authors: Chang Li-Min , Guo Duan-Yi , Lin Kuan-Wu , Tseng Heng-Yi , Li Cheng-Chang , Feng Ting-Mao , Jau Hung-Chang , Wang Chun-Ta , Lin Tsung-Hsien
Published: July 2024

Cholesteric liquid crystals (CLCs) are one-dimensional chiral photonic crystals known for their high tunability. Due to the chirality of the helical superstructure, CLCs exhibit selective Bragg reflection, reflecting only the circular polarization that matches the handedness of the CLC at normal incidence. This characteristic limits the optical performance of CLCs. The total reflection of both circular polarizations (right- and left-handed) can be observed in CLCs at large oblique incidences. However, the narrow bandwidth of this total reflection limits its applications. In this work, we propose a CLC layer with asymmetrical alignment layers to achieve stable bandwidth broadening of the CLC at oblique incidence. The total reflection of both circular polarizations in the CLC is examined experimentally. Compared to conventional planar CLCs, a fourfold increase in the total reflection bandwidth is observed using the proposed method. Additionally, the tunability of the proposed broadening CLC is demonstrated.
Design and manufacture of a modified freeform Offner spectrometer with 0.6× magnification
Authors: Song Lingling , Chen Xinhua , Zhao Zhicheng , Wen Jiawang , Shen Weimin
Published: July 2024

The Offner spectrometer is characterized by a lower F/#, excellent imaging quality, and small distortion, which are beneficial for symmetry and concentricity. However, its 1:1 magnification imposes a constraint on the design, manufacture, and alignment of foreoptics, especially with small F/# applications. The modified Offner spectrometer is hence proposed, and its design and manufacture are introduced in this paper. The initial structure parameters of the modified Offner spectrometer are solved with the wave aberration theory of a plane-symmetrical system. The primary and tertiary mirrors use the Zernike polynomial freeform surfaces to improve the imaging quality during optimization. The components of the designed modified Offner spectrometer are fabricated, and the spectral performance is measured after alignment. The measured spectral resolution is 3.91 nm, and the maximum smile and keystone are 1.37 and 1.8 µm, respectively, which are both less than 10% of the spatial and spectral dimension pixels.
Mechanically sheared axially swept light-sheet microscopy
Authors: Lin Jinlong , Mehra Dushyant , Marin Zach , Wang Xiaoding , Borges Hazel M. , Shen Qionghua , Gałecki Seweryn , Haug John , Abbott Derek H. , Dean Kevin M.
Published: July 2024

We present a mechanically sheared image acquisition format for upright and open-top light-sheet microscopes that automatically places data in its proper spatial context. This approach, which reduces computational post-processing and eliminates unnecessary interpolation or duplication of the data, is demonstrated on an upright variant of axially swept light-sheet microscopy (ASLM) that achieves a field of view, measuring 774 × 435 microns, that is 3.2-fold larger than previous models and a raw and isotropic resolution of ∼460 nm. Combined, we demonstrate the power of this approach by imaging sub-diffraction beads, cleared biological tissues, and expanded specimens.
SkipNet: an adaptive neural network equalization algorithm for future passive optical networking
Authors: Murphy Stephen L. , Townsend Paul D. , Antony Cleitus
Published: July 2024

In this paper, we propose an original adaptive neural network equalizer (NNE) algorithm named SkipNet, which is suitable for rapid training on a packet-by-packet basis for burst-mode non-linear equalization in upstream PON transmission. SkipNet uses the simple LMS algorithm and avoids complex neural network training algorithms such as backpropagation and mini-batch training. We demonstrate SkipNet on captured continuous mode 100 Gbit/s PAM4 signals using an SOA preamplifier to achieve the challenging 29 dB PON optical loss budget. The adaptive SkipNet equalizer is shown to overcome combinations of severe SOA patterning effects and fiber dispersion impairments to achieve >29dB dynamic range back-to-back and >22.9dB dynamic range for up to 81.6 ps/nm accumulated dispersion. It can adapt in as little as 250 training symbols to each impairment scenario, which is equivalent to existing FFE/DFE solutions, while matching the non-linear performance of previously proposed static NNE solutions. To the best of our knowledge, SkipNet is the first ever adaptive NNE framework that can realistically be trained and adapted on a packet-by-packet basis and within strict PON packet preamble lengths.
Study of the interference fringes–caustic region interaction in a topological Young’s interferometer
Authors: Saldivia-Gomez E. , Martinez J. A. , Cubillos-Morales F. , Julian-Macias I. , Martinez-Vara P. , Martinez-Niconoff G.
Published: July 2024

Herein, an analysis of the optical field emerging from a topological Young’s interferometer is conducted. The interferometer consists of two 3D-slit shape curves and is studied by projecting it onto a trihedral reference system. From the projection, Airy, Pearcey, and cusped-type beams emerge. The optical field of these beams is organized around its caustic region. The interference between these types of beams presents interesting physical properties, which can be derived from the interaction between the interference fringes and the caustic regions. One property of the interaction is the irradiance flow, which induces a long-distance interaction between the caustic regions. Another property is the bending of the interference fringes toward the caustic regions, which acts as a sink. Due to the adiabatic features of the caustic regions, the interaction between the fringes–caustic and caustic irradiance is studied using a predator–prey model, which leads to a logistic-type differential equation with nonlinear harvesting. The stability analysis of this equation is in good agreement with the theoretical and experimental results.
Tutorial 2.0: computing topological invariants in 3D photonic crystals
Authors: Devescovi Chiara , Morales-Pérez Antonio , Blanco de Paz Maria , Luis Mañes Juan , Bradlyn Barry , Vergniory Maia G. , García-Etxarri Aitzol
Published: July 2024

The field of topological photonics has been on the rise due to its versatility in manufacturing and its applications as topological lasers or unidirectional waveguides. Contrary to 1D or 2D photonic crystals, the transversal and vectorial nature of light in 3D precludes using standard methods for diagnosing topology. This tutorial describes the problems that emerge in computing topological invariants in 3D photonic crystals and the diverse strategies for overcoming them. Firstly, we introduce the fundamentals of light propagation in 3D periodic media and expose the complications of directly implementing the usual topological diagnosis tools. Secondly, we describe the properties of electromagnetic Wilson loops and how they can be used to diagnose topology and compute topological invariants in 3D photonic crystals. Finally, we apply the previously described methods to several examples of 3D photonic crystals showing different topological phases, such as Weyl nodes and walls, 3D photonic Chern insulators, and photonic axion insulators.
Approaching the optimal phase estimation sensitivity of the lossy Mach-Zehnder interferometer with coincidence measurements
Authors: Li J. H. , Feng X. N. , He D. , Hu W. Y. , Song H. Z. , Wei L. F.
Published: July 2024

How to find the specific measurement scheme to approach the quantum Cramér-Rao bound (QCRB) is an important issue in quantum metrology, especially for the continuous-variable optical interferometers input with non-classical states. In the ideal situation (i.e., without any photon loss), this can be usually achieved by using the parity measurement, which, however, does not work well when the photon loss occur. Alternatively, in this work we find that the coincidence measurements are more robust to the photon loss than the parity measurement. Importantly, in certain cases, the sensitivity with the coincidence measurement can even approach very closely to the QCRB despite of the photon loss. Though the results are obtained based on the analysis with the typical two-photon twin-Fock state, it might be also generalized for the other input ones. Thus, our work may provide an effective measurement scheme for beating the shot-noise limit in practical experiments.
X-ray dark-field via spectral propagation-based imaging
Authors: Ahlers Jannis N. , Pavlov Konstantin M. , Kitchen Marcus J. , Morgan Kaye S.
Published: July 2024

Dark-field X-ray imaging visualizes scattering from unresolved microstructure. Most dark-field imaging techniques rely on crystals or structured illumination, but recent work has shown that dark-field effects are observable in straightforward propagation-based imaging (PBI). Based on the single-material X-ray Fokker–Planck equation with an a priori dark-field energy dependence, we propose an algorithm to extract phase and dark-field effects from dual-energy PBI images. We successfully apply the dark-field retrieval algorithm to simulated and experimental dual-energy data, and show that by accounting for dark-field effects, projected thickness reconstruction is improved compared to the classic Paganin algorithm. With the emergence of spectral detectors, the method could enable single-exposure dark-field imaging of dynamic and living samples.
Wavefront-corrected high-intensity vortex beams exceeding 1020  W/cm2
Authors: Lee Sunwoo , Yoon Jin Woo , Sung Jae Hee , Lee Seong Ku , Kim Seung Yeon , Yang Jeong Moon , Hwang Sung In , Nam Chang Hee , Yeo Woo-Jong , Jeong Seok-Kyeong , Jeon Minwoo , Choi Hwan-Jin , Kim Mincheol , Kim Dong Uk , Lee Kye-Sung , Chang Ki Soo , Pak Soojong , Choi Il Woo , Kim I Jong
Published: July 2024

The use of vortex laser beams has increased in various areas of optics and photonics, necessitating enhanced beam quality for wide usage. In the field of high-power lasers, a range of methods to implement vortex laser beams has been proposed. Nonetheless, enhancing beam quality becomes more challenging as the laser power increases. This study presents the successful implementation of a high-quality, high-intensity vortex laser beam exceeding 1020W/cm2—an essential advancement for enhancing the performance and applicability of high-power lasers. We achieved this by integrating a spiral phase mirror (SPM) with an orbital angular momentum of l=1, specially designed for the vortex beam, along with an adaptive optical system, into a 150-TW femtosecond Ti:sapphire laser. Importantly, SPM, featuring a modulation structure to correct for a 45° incidence angle, was utilized to produce the vortex beam. The adaptive optical system, comprising a Shack–Hartmann wavefront sensor and a deformable mirror, employed a feedback loop to correct wavefront aberrations distorting the vortex beam. Notably, the negligible difference between the Hartmanngrams of the Gaussian and vortex beams (l=1) allowed the Gaussian beam’s Hartmanngram to serve effectively as the input reference for wavefront correction, resulting in a successfully corrected vortex beam wavefront. Experimental results, both pre- and post-wavefront correction, were compared with simulation results obtained via field-tracing. The peak intensity of the focused high-quality vortex laser beam ultimately reached 1.8×1020W/cm2, exceeding previously reported experimental results. The results of this study could significantly contribute to the exploration of high-intensity angular momentum transfer in relativistic laser-plasma interactions.
Physics-informed generative network for phase retrieval from a single intensity measurement
Authors: Yang Xiaogang , Hailu Dawit , Kulvait Vojtech , Jentschke Thomas , Wong Tak Ming , Flenner Silja , GREVING IMKE , Hagemann Johannes , Campbell Stuart , Schroer Christian , Moosmann Julian
Published: July 2024

This study presents a deep learning algorithm for solving the inverse problem of phase retrieval in the optical near-field (Fresnel) regime using a single intensity measurement (in-line hologram). The algorithm was developed in a self-learning fashion based on generative adversarial networks (GANs) for tomographic reconstruction (GANrec). In this paper, the original GANrec algorithm is adapted to solve the phase retrieval problem. From a single hologram, GANrec can recover both phase and amplitude of the unpropagated exit wave field. Compared with other state-of-the-art deep learning approaches for phase retrieval, it does not need any training data. GANrec combines the advantage of an optimization-based reconstruction with the ideas of machine learning and generative models. It iteratively minimizes the difference between the measured hologram and generated hologram. The results of the validation show good quality of the phase recovery. The idea can work universally for many ill-posed inverse problems if the forward model is well defined.