bluuebunny/crossref_metadata_2025 huggingface dataset:
Validation of the diagnostic accuracy of neutrophil to lymphocyte ratio (NLR) and mean platelet volume (MPV) in cirrhotic patients with spontaneous bacterial peritonitis
Authors: Abudeif Ahmed , Elbadry Mahmoud Ibrahim , Ahmed Nesma Mokhtar
Published: February 2023

Background

Spontaneous bacterial peritonitis (SBP) is a significant complication among cirrhotic patients with ascites and is associated with high mortality. Early diagnosis and treatment of SBP are crucial, as they are associated with better outcomes and lower mortality. The neutrophil-to-lymphocyte ratio (NLR) and mean platelet volume (MPV) are routine, inexpensive, easily measured markers readily obtained from a complete blood count (CBC). Several studies have addressed the diagnostic role of NLR and MPV in patients with SBP but with different cutoff values, sensitivity, and specificity. Therefore, we conducted this study to validate the clinical utility of NLR and MPV in diagnosing SBP.

Methods

This study included 332 cirrhotic patients with ascites who were admitted to Sohag University Hospitals in Egypt between April 2020 and April 2022. Of these patients, 117 had SBP, and 215 did not. Both NLR and MPV were measured in all patients, and the ability of NLR and MPV to diagnose SBP was assessed using the receiver operator characteristic (ROC) curve analysis.

Results

NLR and MPV were significantly elevated in patients with SBP compared to those without SBP (P < 0.001). At a cutoff value of 5.6, the sensitivity and specificity of the NLR in detecting SBP were 78% and 81%, respectively. In contrast, MPV, at a cutoff value of 8.8 fL, had a sensitivity of 62% and a specificity of 63%. The combination of NLR and MPV did not provide significant additional diagnostic value beyond only using NLR.

Conclusion

Although NLR and MPV allow the detection of SBP, the NLR has higher clinical utility and is superior to MPV in diagnosing SBP.
Machine-learning inversion via adaptive learning and statistical sampling: Application to airborne micro-TEM for seismic sand corrections
Authors: Colombo Daniele , Turkoglu Ersan , Sandoval-Curiel Ernesto , Rovetta Diego , Li Weichang
Published: February 2023

We develop a novel physics-adaptive machine-learning (ML) inversion scheme showing optimal generalization capabilities for field data applications. We apply the physics-driven deep-learning inversion to a massive helicopter-borne transient electromagnetic (TEM) field data set. The objective is the accurate modeling of the near surface for enhancing the exploration of low-relief structures in a sand covered desertic area. Enhanced generalization of a neural network (NN) or other ML techniques is obtained from automatic physics-based adaptive training using images of real-world data. Data reduction schemes, based on statistical sampling techniques, enable the use of small and fully informative data sets for accelerated training. Adaptive learning is implemented via an iterative physics-driven data augmentation strategy. A deterministic inversion is regularized by a penalty term built from the difference between the inverted models and the models predicted by ML. The resulting inverted models and calculated responses are used for augmenting the ML training base. The automated procedure converges rapidly, producing a trained network model, which captures the general background data statistics as well as the characteristics of field-specific geophysical data as embedded in the augmented samples. The high-resolution ML inversions with acceptable levels of data misfit are obtained for large volumes of the field geophysical data. We test several different learning models, such as artificial NNs, convolutional NN (U-Net), and the Gaussian process, which provide stable and comparable results with network-specific characteristics. The developed scheme is successfully applied to micro-TEM data providing accurate near-surface seismic corrections for the exploration of low-relief structures.
Erector Spinae Plane Block for Scapulothoracic Arthrodesis for Facioscapulohumeral Dystrophy Patients: A Case Series
Authors: Gürkan Yavuz , Sincer Yasemin , Manici Mete , Gedik Cemil Cihad , Eren İlker , Demirhan Mehmet
Published: February 2023

Facioscapulohumeral dystrophy (FSHD) typically affects the periscapular muscles, resulting in scapular winging. Scapulothoracic arthrodesis (STA) stabilizes the scapula to provide better movement for these patients. Analgesia regimen for FSHD patients who received a single-shot erector spinae plane block (ESPB) and a catheter at the area were retrospectively analyzed in this study. Patients were asked to rate their pain postoperatively and only 5 of 10 patients needed rescue analgesic. No complications occurred. Our experience suggests that continuous ESPB may be helpful for providing analgesia in FSHD patients undergoing STA.
How to Read The Pentagon Papers
Authors: Puckett Kent
Published: February 2023

This essay understands what it meant and what it means to read The Pentagon Papers in a few related ways. First, when it appeared in 1971, there were at least three different versions of the Papers available. Because, in other words, the reader had to choose between versions from the very start, The Pentagon Papers had to be read both as a text and as a textual event. Second, although the Papers are often remembered as an unmediated document dump, the whole was, in fact, a highly mediated and intensely narrative document, an effort to present the incoherent story—the violence—of Vietnam as a coherent discourse. As a result, they not only demand but also assume interpretation. Finally, the fact that Leslie Gelb, the Department of Defense editor of the Papers, officially introduced its more than seven thousand pages with a pointed reference to Moby-Dick encourages us to look for and to understand how something unexpectedly novelistic supports and maybe subverts the documentary force of The Pentagon Papers.
Open-Circuit Narrative: Programmed Reading in Richard Powers
Authors: Stewart Garrett
Published: February 2023

Long before the eight-stranded weave of ecocritical plot in Richard Powers's Pulitzer Prize–winning The Overstory (2018) and, since then, the interlace between inset astrobiological bedtime stories and the environmentalist passions of family psychodrama in his Booker-nominated Bewilderment (2021), an important turn-of-the-millennium work by this MacArthur-lauded novelist, Plowing the Dark (2000), remains his most strenuous venture in what this article calls the open-circuit structure of his typical multi-plot narratives. Scenes of secretly funded VR aesthetics in the high-tech America of “research and development” are pitted against the contrasting affect, emphatically detached in space and time, of savage sensory deprivation suffered by an Arab American US citizen as jihadist prisoner in Beirut. Only at the eleventh hour of plot time is this man's plight revealed, by proximate cause, to render him, in retrospect, the indirect victim (spoiler alert) of electronic sophistication in American's “wired wars.” Until then, reading swerves between alternate and seemingly unrelated spaces of cyber-optic volatility and cognitive evacuation, virtual over against vitiated—with an all-too-real network of violence hard-wiring them imperceptibly to each other. Beyond the latent dialectic of these disjunct prose episodes, the novel critiques a world “formed” on quite different principles, whose geopolitical systems it confronts on fiction's own resistant verbal terms. To argue the contrary—that literary and societal forms are different from each other only in degree or scale—is, in an especially leveling sense, to rescind crucial differences between the force of depiction and world of force, which every lucid nuance of Powers's unique narrative style would resist.
Keeping Quiet in Tove Jansson's Fair Play
Authors: Yamaguchi Liesl
Published: February 2023

As a follow-up to the Common Knowledge symposium “Apology for Quietism” (15:1 to 16:3), this guest column asks what it means to say nothing. Strictly speaking, to “say nothing” is a contradiction in terms (unless, of course, one says “Nothing,” which is another thing entirely and generally not nothing). This essay explores what it means to say nothing in Tove Jansson's novella Fair Play (first published in Finland Swedish as Rent spel, 1989), an episodic account of the intertwined lives of two elderly artists. Through its careful staging of saying nothing, the text calls attention to the many vital functions that silence serves: exposing tacit expectations, opening up creative and psychological space, enabling otherwise impossible relations. Bringing forth the diversity, complexity, and mystery behind hesitation and reticence, Jansson's novella emerges here as a quiet celebration of conversational practices associated with weakness, redefining the genre of the “love story” along the way.
Contingency All the Way Up
Authors: Mutter Matthew
Published: February 2023

This review-essay examines two books about the history of the modern humanities: Permanent Crisis: The Humanities in a Disenchanted Age by Paul Reitter and Chad Wellmon and Battle of the Classics: How a Nineteenth-Century Debate Can Save the Humanities Today by Eric Adler. Both studies reconstruct genealogies of discourse and practice by which to understand the “crisis” of the humanities, yet they draw disparate lessons from these reconstructions. The review traces the two monographs’ competing accounts of the historical continuity of humanities practices and the moral dimension of humanistic inquiry. Together, Permanent Crisis and Battle of the Classics describe an antinomy that can be neither resolved nor ignored: the methodological norms of the modern university tend to subvert the humanities’ investment in meaning and value, but without that investment, humanistic study loses the motivations and purposes that define it.
Rereading a Poetics of Divination: Oracular Visuality and Iterations of Landscape in Wei-Jin Lyricism
Authors: Noel Thomas Donnelly
Published: February 2023

While Chinese poets of the early medieval period have long been credited with the development of shanshui 山水 (landscape) poetry, the precursors of the prosody they employed merit further scrutiny. This article argues that an ancient poetics of visual augury informed early medieval shanshui lyricism and that similar iterations of nature writing emerged earlier than is often recognized. By tracing the use of the divinatory utterance yangfu 仰俯 (looking up and looking down) in earlier depictions of the natural world, the author reconsiders the visual poetics of later shanshui literature alongside texts that use analogous mantic terminology. This study concludes that, while China's first “nature poets” constructed imagery, lyrics, and personae that appear distinct if not even contradictory to one another, the poets relied on a common visual prosody derived from preestablished mantic approaches to the natural world and its representation. In so doing, this article also further highlights the underappreciated prosodic and ideological indebtedness of later shanshui poets to the authors of the Eastern Han and provides insight into the correlations that ran between diverse forms of linguistic visuality and the poetic explorations of the natural world in early China.
Space and Identity: Self-Representation of a Ming Nanjing Courtesan in Transformation
Authors: Chen Jiani
Published: February 2023

This article examines the poetic collections of the Ming woman writer Yang Wan 楊宛 (ca. 1600–ca. 1647), whose transformation of identity from a courtesan celebrity to a gentry wife was one of the most representative in the category of courtesan turned concubine/wife. Her marriage lasted for decades, and her role as a family woman fully developed over time. By approaching her writings from the perspective of space, it reveals how a woman perceived and interpreted her changing status by framing her self-representation and emotional expression within two feminine spaces: the pleasure quarter and the inner chamber. Yang Wan's identity transformation and her strategic exploration of the gendered spaces along with their diverse symbolic codes contribute to our knowledge of the social, textual, and cultural mobility of late imperial China.
Development of advanced methodologies based on high resolution mass spectrometry for food of animal origin authenticity characterization
Authors: Κρητικού Αναστασία
Published: February 2023

Η οικονομικά υποκινούμενη αντικατάσταση συστατικών των τροφίμων με πιο άφθονες και φθηνότερες, έχει οδηγήσει σε επιτακτική ανάγκη ανάπτυξης αναλυτικών μεθοδολογιών για τη διασφάλιση της αυθεντικότητας τους. Τα τρόφιμα ζωικής προέλευσης, ειδικότερα εκείνα που φέρουν ενδείξεις όπως Προστατευόμενης Ονομασίας Προέλευσης (ΠΟΠ), βρίσκονται στο επίκεντρο τέτοιων δόλιων πρακτικών λόγω της υψηλής διατροφικής τους αξίας και της ευρείας κατανάλωσής τους. Ως προς αυτή την πτυχή, έχει θεσπιστεί ένα ευρύ φάσμα κανονισμών για τη διασφάλιση της αυθεντικότητας και την προστασία των καταναλωτών, ωστόσο, υπάρχει ακόμη περιθώριο για τη βελτίωση των υπαρχουσών μεθοδολογιών. Η Φασματομετρία Μαζών Υψηλής Διακριτικής Ικανότητας (HMRS) αποτελεί μείζονος σημασίας αναλυτική τεχνική ως προς τη συνεισφορά της σε ζητήματα αυθεντικότητας, παρέχοντας γρήγορα, αναπαραγώγιμα και αξιόπιστα αποτελέσματα.Σε αυτή τη διατριβή, παρουσιάζεται μια εκτενής εισαγωγή στις μελέτες αυθεντικότητας τροφίμων ζωικής προέλευσης με βάση τις ωμικές προσεγγίσεις, καθώς και το αντίστοιχο νομοθετικό πλαίσιο. Περιγράφονται αναλυτικά οι υπάρχουσες HRMS μεθοδολογίες σε συνδυασμό με χημειομετρικά εργαλεία, ενώ παράλληλα γίνεται εκτενής αναφορά στις δυνατότητες των σύγχρονων HRMS τεχνικών. Το πειραματικό μέρος αποτελείται από τα ακόλουθα τρία μέρη: (i) Αξιοποίηση τεχνολογίας MALDI-HRMS για την ανάπτυξη γρήγορων και αξιόπιστων προηγμένων μεθοδολογιών για τη διερεύνηση αυθεντικότητας γαλακτοκομικών προϊόντων (Κεφάλαιο 3), (ii) RP- & HILIC-HRMS αναλυτικές πλατφόρμες 3D-μεταβολομικής για μελέτες αυθεντικότητας γαλακτοκομικών προϊόντων (Κεφάλαιο 4) και (iii) Στοχευμένη και μη στοχευμένη 4D-μεταβολομική για τη διερεύνηση αυθεντικότητας ζωικών μυϊκών ιστών, αξιοποιώντας RP- & HILIC-HRMS αναλυτικές πλατφόρμες ενσωματωμένες με Φασματομετρία Ιοντικής Ευκινησίας (LC-TIMS-TOFMS) (Κεφάλαιο 5).Η αξιοποίηση των HRMS μεθοδολογιών, που παρουσιάζεται σε αυτή τη διατριβή, δίνει τη δυνατότητα δημιουργίας ολιστικών προσεγγίσεων τεκμηρίωσης της αυθεντικότητας, συμβάλλοντας στην διαλεύκανση του περίπλοκου αναλυτικού τοπίου, όσον αφορά τα τρόφιμα ζωικής προέλευσης.
Introducing the Tele-OCS: A validated remotely administered version of The Oxford Cognitive Screen
Authors: Webb Sam S. , Carrick Chloe , Kusec Andrea , Demeyere Nele
Published: February 2023

Background

Remote cognitive assessments are increasingly used with the rising popularity of teleneuropsychology. Here, we evaluated the performance of the remotely administered Oxford Cognitive Screen (Tele-OCS) compared to in-person administration in adult stroke survivors.

Methods

40 stroke survivors (M age = 69.30, SD = 10.44; sex = 30% female) completed in-person and remote versions of the OCS on average 30 days apart, with different trained examiners. The order of administration was counterbalanced. Cohen’s d estimates were used to compare performance between modalities.

Results

We found that the proportion of OCS subtasks impaired did not differ across modalities (d = 0). With regards to raw subtask scores, only the picture naming subtask and executive score from the trail making subtask were found to be statistically different across modalities, though raw differences were minimal (<1 point difference on average). These statistical differences did not affect impairment classifications.

Conclusions

The Tele-OCS classified cognitive impairments in a comparable way to the in-person version. The validation of the Tele-OCS allows for remote assessment to increase accessibility and pragmatically aid in addressing the clinical need for stroke-specific cognitive screening in a wider population.
Criticism of media speech
Authors: Vasil'eva Viktoriya , Duskaeva Liliya , Ivanova Lyubov' , Konyaeva Yuliya , Malyshev Aleksandr , Samsonova Anastasiya , Cvetova Natal'ya , Basovskaya Evgeniya
Published: February 2023

Criticism of media speech is one of the directions in media linguistics based on the assessment of the quality of speech activity in the mass media. Within the framework of this direction, several subdisciplines have already been formed, each of which has its own approaches to the development of problems of the norm and the assessment of compliance with it. The manual contains two sections. The first one is devoted to the praxiolinguistic criticism of media speech. It shows how the use of the axiological scale of speech behavior in the media "effectively — permissible (unsuccessful — unacceptable — prohibited)" can assess the quality of business, art and sports journalistic discourse. The second section explains how to assess conflict media and diagnose speech crimes in the media. In the course of working with the book, students are taught to separate professional and non—professional speech in the media, to assess the quality of language and speech in media texts, or rather, the quality of the selection of language tools and speech resources, correlating the result of journalistic activity with social, general cultural language and speech norms — appropriate, permissive, binding, prohibiting. The work with the manual is designed to form eco-speech competence in the media and contributes to the formation of speech media literacy.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
For students of educational departments studying in the areas of "Journalism", "Advertising" and "Public Relations".
Budget and budget system of the Russian Federation
Authors: Arkad'eva Ol'ga , Berezina Nataliya , Tat'yana Vital'evna.
Published: February 2023

The textbook discusses the theoretical and practical aspects of the functioning of the budget system, the organization and implementation of the budget process.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
For students enrolled in bachelor's degree programs in the areas of preparation 38.03.01 "Economics", 38.03.04 "State and municipal administration" and specialty programs in the direction of preparation 38.05.01 "Economic security", university teachers, as well as for a wide range of readers interested in the organization of the budget system.
Applied neuro-fuzzy computing systems and devices
Authors: Bobyr' Maksim , Emel'yanov Sergey , Arhipov Aleksandr , Milostnaya Natal'ya , Ronzhin Andrey , Mescheryakov Roman
Published: February 2023

The monograph is devoted to the analysis and development of applied neuro-fuzzy systems and devices. The issues related to the training of neuro-fuzzy inference systems are outlined. There are many examples and algorithms that explain the essence of the functioning of the developed methods.
It is intended for students, postgraduates, researchers, engineers engaged in the development of intelligent systems and devices for controlling mechanisms.
Electronic voting: Russian and foreign experience
Authors: Fedorov Vladislav , Sel'cer Dmitriy , Bykov Il'ya , Alekseev Roman
Published: February 2023

The monograph is devoted to the problems of the development of electronic voting abroad and in Russia. Based on the materials of 12 countries (Belgium, Brazil, Bhutan, Venezuela, India, Kyrgyzstan, Mongolia, Namibia, Philippines, Switzerland, Estonia, Russia), where the electoral legislation provides for the use of electronic voting in national elections throughout the country, the issues of the impact of electronic voting on voter turnout and confidence in the elections are considered, identified trends in the development of electronic voting and factors influencing the choice of its form.
It is intended for students, postgraduates, teachers of political science and constitutional law, for training election organizers and other participants in the electoral process, as well as for a wide range of readers interested in modern political processes.
Flat farms. Schemes and calculation formulas: a reference book. Volume 3
Authors: Kirsanov Mihail , Kozlov Vladimir
Published: February 2023

The reference book contains diagrams of flat regular statically definable arched, frame and cantilever trusses. Formulas are given for calculating the forces in the rods and deflection of structures depending on the number of panels. An algorithm for obtaining analytical solutions in the Maple computer mathematics system is described. Cases of kinematic variability of some truss schemes are considered.
Designed for engineers, researchers, students and postgraduates of technical universities.
Efeito agudo da prática esportiva com engajamento cognitivo nas funções executivas em crianças
Authors: Florêncio Júnior Públio Gomes , Nascimento Tárcio Amancio do , Silva Harrison Vinicius Amaral da , Costa André dos Santos
Published: February 2023

O objetivo do presente estudo foi avaliar o efeito agudo da prática de uma sessão de futsal com engajamento cognitivo na memória de trabalho e no controle inibitório de crianças. Trata-se de um estudo controlado e randomizado com abordagem quantitativa do tipo Crossover. Foram recrutadas 33 crianças (com idade entre 8 e 10 anos) de ambos os sexos que foram submetidas a duas sessões experimentais: 1) Sessão jogo com duração de 15 min baseada no futsal com maiores demandas de engajamento cognitivo. 2) Sessão controle que consistiu em 15 min de repouso em uma sala. Foram aplicados imediatamente antes e após as sessões o DigitSpan e o Stroop Test para avaliar a memória de trabalho e o controle inibitório, respectivamente. As equações de estimativas generalizadas foram utilizadas para verificar a interação entre o tempo e as intervenções. Os resultados indicaram interação sessão*tempo significativa para a memória de trabalho, precisamente na ordem direta do DigitSpan, indicando aumento significante de pré para pós-intervenção para a sessão jogo com um tamanho de efeito pequeno (p = 0,012; d = 0,38). Após a sessão jogo, as crianças também apresentaram melhora significativa, com tamanho do efeito médio na acurácia da fase incongruente (p = 0,008; d = 0,63) do Stroop Test e menor tempo para resposta em comparação à sessão controle (p = 0,029). O estudo apontou que a atividade física com engajamento cognitivo teve efeito sobre o controle inibitório de crianças.
Oral Health Status and Dental Care of Disable Children
Authors: Ankhi Rumana Nahid , Hoque Mohima Benojir , Bhuiyan Md Amanul Islam , Akter Mahmuda , Saha Sujoy
Published: February 2023

Now a days disability has becomes a great problem. But in dental care, facilities for them are very rare. For the purpose of doing something for disable children a study on oral health status and dental care of disable children was conducted in CRP, Mirpur, Bangladesh. To identify the oral health status of disable children in Dhaka city, Bangladesh. A cross sectional study to assess the oral health condition of disable children was conducted. Data were collected from 125 disable children attending in CRP, Mirpur, Dhaka, Bangladesh through purposive sampling technique. Study shows that there was very poor knowledge on brushing technique. 55% brushed their teeth like brush upper teeth from above downward, lower from below upward and side to side movement.64.8% brushed their teeth before breakfast and 17.4% before breakfast and after dinner and others brushes their tooth in other times. 60% had halitosis, and caries rate was 49%. Most of them had abnormal oral habit.80% children had bruxism, 75% had multiple abnormal oral habit. 38.9% had mouth breathing. 63% never visit to a dentist and 20% had visit dentist when they suffered from dental pain.12% visit dentist once a year and only 4% visited dentist for regular check-up. 34% of respondents did not follow proper oral health hygiene. They took care of their teeth by their own method. 20% informed by dental health professional, 18.4% by dentist, 1.6% by radio, 24% by television and 0.8% from printed materials. Most of the participants did not have proper hygienic knowledge as a result they did not take proper dental care. Caries rate was increased with the increase of their age because they did not brush their teeth regularly. Dental health professionals and dentist should work to aware people about oral health status and proper dental care especial program should be arranged for disable children.
Effect of Sawing Variation on Hardwood Lumber Recovery—Part II: Board Count
Authors: Thomas Edward , Buehlmann Urs
Published: February 2023

Sawing variation (SV) describes all variations that exist in the production of lumber due to machine, material, set works, feed works, and cutting parameters. The necessary oversizing of board thickness due to SV diminishes sawmill profits and hence efforts must be made to reduce the variation. However, such efforts are costly and sawmill personnel generally do not know at which point efforts to reduce (SV) become more costly than oversizing the boards. In an accompanying paper we examined the impact of SV on lumber volume recovery and found that volume recovery increased comparatively more for thinner than for thicker kerfs and that the effect of reduced SV became more pronounced as diameter increased. In this second manuscript, the effect of SV on the quantity of boards sawn for a range of hardwood log diameters using the US Forest Service's LOg ReCovery Analysis Tool sawmill simulation software was researched and compared with the volume improvement from an earlier paper. Results showed that significant differences in the number of boards obtained was dependent on the log diameters sawn, the lumber target thickness, and the change (reduction) in SV. A minimal average recovery improvement of 3 percent due to reduced SV was observed across all kerf thicknesses, equating to a potential production value improvement of $336,000 for an 8 million board feet mill. All sawmills can benefit from reducing SV, but mills that saw large-diameter logs might consider pursuing SV reduction more aggressively than a sawmill sawing mostly small-diameter logs.
Confusion Lines of Protanopes and Deuteranopes
Authors: Fry Glenn A.
Published: February 2023

Let us use a rectangular coordinate diagram (Fig. 1) to represent mixtures of three primary colors 700, 600 and 400 nm. The diagram applies to any given individual who may be a protanope, a deuteranope or a normal observer. R, G and B represent the amounts of the three primaries in a given mixture expressed in luminance units.
Novel Adaptive Optics with the Durham University ELECTRA System
Authors: Buscher D.F. , Andrews N. , Dunlop C. , Morris P.W. , Myers R.M. , Sharpies R.M. , Vick A.J.A. , Zadrozny A. , Haniff C.A. , Wilson R.W.
Published: February 2023

We present the status of the Durham University ELECTRA visible-light adaptive optics system and describe novel imaging strategies to be used with this instrument.
Low Light Level Fringe Visibility Estimation with Adaptive Optics
Authors: Gamiz Victor L.
Published: February 2023

The source image spectrum obtained by imaging interferometry is derived from measurements of the interference fringe visibility and phase from pairs of apertures. Most interesting sources are dim and of small angular extent requiring observations in the low light level regime over large baselines. The use of large individual apertures increases the amount of light but requires some form of adaptive optics to mitigate the effects of the atmosphere and maintain the spatial coherence across baselines. We outline the mathematical formalism for quantifying the error in estimating the fringe visibility and phase with varying amounts of spectral bandwidth, radiometric signal-to-noise, atmospheric seeing, individual aperture diameter, baseline dimension, fringe tracking, tilt removal, and higher order Zernike mode removal. This work describes the proper aperture wavefront covariances across arbitrary baselines with the proper Kolmogorov atmospheric statistics, assumed independent by other works. Photon noise, detector noise, and spectral bandwidth dependent photon counting statistics are included. The effects from the use of single mode fiber optics to transport the beams are also described. Numerical results describing the sensitivity of the fringe estimates to the above parameters are presented for typical array geometries for observing geosyncronous satellites.
Adaptive optics requirements for a ground-to-space laser communications system
Authors: Tyson Robert K.
Published: February 2023

Advances in adaptive optics have made it possible to consider their use to enhance ground-to-space laser communications systems. Adaptive optics are used to counteract the effects of atmospheric turbulence and deliver a beam undistorted through the atmosphere. This paper examines the system level requirements of an adaptive optical system in terms of communication parameters. An optical communications link must deliver a modulated beam to a receiving sensor with minimal distortion of the modulated signal. Distortion which stretches pulses, distorts pulse shapes, or otherwise randomizes the pulse intensity or location contributes to a higher bit error rate. The ability of adaptive optics to compensate for atmospheric scintillation is studied with respect to its effect on signal fade and surge.
A Computationally Efficient Method for Wavefront Reconstruction
Authors: Browne Stephen , Vaughn Jeff , Tyler Glenn , Gonglewski John D.
Published: February 2023

A fast algorithm for measuring Hartmann spot positions is combined with a computationally efficient reconstructor running on a pair of i860XP processors to achieve 1000 reconstructions per second. The full-featured reconstructor removes unobservable modes, as well as tilt which is handed to a steering min or with high dynamic range. Moreover, the reconstructor can perform much of its processing on the fly while the frame is being transferred from the pupil plane camera, resulting in significantly reduced servo phase lag. Details of the fast reconstructor are described with particular emphasis on the creative use of computational resources.
Simulation of Adaptive Secondary Mirror Dynamic Response
Authors: Biasi R. , Gallieni D. , Mantegazza P.
Published: February 2023

This work is part of a study that aims at implementing adaptive optics on a secondary mirror of an 8 m class astronomical telescope for atmospheric compensation at visible wavelength. The secondary mirror to be controlled is a continuous thin facesheet type. The goal is to fulfill operational specifications by using voice coils actuators coupled to collocated capacitive position transducers.
Control Loop Analysis and Characterization for an Adaptive Optics Experiment on the Starfire 3.5m Telescope
Authors: Browne Stephen , Vaughn Jeff , Tyler Glenn , Gonglewski John D. , Dayton David , Sandven Steven , Laughlin Darren , Highland Ron
Published: February 2023

Au experiment with a nasmyth adaptive optics system mounted on the SOR 3.5m telescope employs an adaptive optical imager. A 148-subaperture hexagonal lenslet array provides a Hartmann wavefront sensor for the 163 actuator mirror to which it is mated. Our analysis of the control loop of the adaptive optical system is edified, and the actual implementation is explained. Performance tradeoffs between various subaperture geometries, based on reconstructor noise gain and stability considerations, are presented. A fast algorithm for measuring Hartmann spot positions is combined with a computationally efficient reconstructor running on a pair of i860XP processors to achieve 1000 reconstructions per second. Moreover, the reconstructor can perform much of its processing on the fly while the frame is being transferred from the pupil plane camera, resulting in significantly reduced servo phase lag. We describe the control loop design, with particular emphasis on the creative use of hardware data paths.
Diffraction-Limited Wide-Field Sky Camera
Authors: Bingham Richard G.
Published: February 2023

I show the optical design for a wide-field sky camera of two meters aperture diameter. It has much better performance than existing cameras and can be diffraction limited over a field of view of two degrees diameter, and over a wide range of wavelengths. I point out the problems of implementing such a high performance optical system. I discuss how it might conceivably be exploited, for example, by using more than one adaptive optics system.
Potential Application of Coherent Population Trapping to Adaptive Optics and Turbulence Metrology
Authors: Hemmer P. R.
Published: February 2023

Coherent population trapping (CPT) in multilevel Raman resonant atomic systems is a fast, efficient process which produces large optical nonlinearities at low laser intensities. These properties are potentially useful in turbulence metrology and adaptive optics, especially for severe turbulence. To illustrate this, three experimentally demonstrated properties of CPT will be described and their possible application will be outlined.
Laser beacon compensated images of Saturn using a high speed near infrared correlation tracker
Authors: Fugate Robert Q. , Riker James F. , Roark J. Timothy , Stogsdill Steve , O’Neil Burt D.
Published: February 2023

The 1.5 m telescope at the Starfire Optical Range, USAF Phillips Laboratory, Albuquerque, NM, USA is equipped with laser beacon adaptive optics and a high speed full aperture tilt correction system. The laser beacon is formed by a copper vapor laser propagated out the full 1.5 m aperture and focused at 14 km range. The laser operates at 5,000 pulses per second, 50 ns per pulse, with approximately 60-70 watts average power into the atmosphere. Light backscattered from the laser beacon between the ranges of 12 and 16 km is sensed by an unintensified, Pockels-cell-gated, silicon-based CCD Shack-Hartmann wave front sensor. The optics are configured such that it is also possible to use natural stars as beacons for the higher-order adaptive optics. Wave front corrections are applied to a 241 actuator continuous facesheet deformable mirror operated at approximately 100 Hz closed loop bandwidth.
Keck Adaptive Optics: Test of a Deformable Mirror in a Freezing Environment
Authors: Acton D. S. , Stomski P. , Wizinowich P. , Maute J. , Gregory T. , Ealey M. , Price T.
Published: February 2023

The W. M. Keck Observatory and Lawrence Livermore National Labs are currently developing an adaptive optics system for use on Keck II--a 10.8-meter segmented telescope. This AO system will make use of a 349-actuator deformable mirror (DM). The Keck II telescope sits atop Hawaii’s Mauna Kea, where the ambient nighttime temperature varies between -5 and 5 degrees C. In order to reduce dome seeing, and to minimize the thermal emissivity, the AO system (and hence the DM) will be cooled to the ambient temperature of the outside air. Therefore, we are motivated to use actuators in the DM that are optimized for operation at 0 degrees C.
A Modular Adaptive Optics System
Authors: Toledo-Quinones Manuel , Nagano Junko , Landers Frank , Weibel Steve , Levine B. Martin
Published: February 2023

A modular, commercially available adaptive optics system is described. Appropriate for small laboratories exploring new applications of adaptive optics, the system combines advances in the construction of high speed computers and deformable mirrors to offer closed loop bandwidths of up to 50 Hz with 37 actuators of control.
Focal Enlarger for the CFHT Adaptive Optics Bonnette
Authors: Barrick Gregory
Published: February 2023

SUMMARY: The Canada-France-Hawaii Telescope (CFHT) has recently tested, on the sky, our new adaptive optics bonnette (PUEO). PUEO, in the process of correcting the incoming wavefront, converts the f/8 beam of the telescope into an f/20 beam. To ensure well-sampled images at 0.07 arc-second, the best expected images with PUEO, a focal enlarger was built to convert the f/20 beam, with at plate scale of 0.043 arc-seconds/pixel on a 15 μm pixel CCD, to an f/40 beam, with a plate scale of 0.021 arc-seconds/pixel.
Aluminum Gallium Arsenide/Gallium Arsenide Photon Counting Cameras for Very Low Light Level Wavefront Sensing
Authors: Loos Gary C. , Sinor Timothy W. , Abraham J. M.
Published: February 2023

The feasibility of using adaptive optics (AO) systems on large ground based optical telescopes for producing compensated images of both astronomical sources and artificial earth satellites has been demonstrated by a number of research groups. AO systems consist conceptually of a wavefront sensor (WFS) which measures atmospherically induced wavefront phase perturbations faster than the rate at which they occur and a wavefront phase compensation device, typically a deformable mirror, which takes the WFS data and produces a conjugate phase correction nulling the distortion. In the case of faint sources, the ability of an AO system to produce phase corrections is limited by the signal-to-noise ratio (SNR) in the WFS. In the case of the Shack Hartmann (SH) WFS this limit is a function of the SNR required to estimate with sufficient accuracy the centroid positions of unresolved images of the source formed by a lenslet array on an array of quadrant detectors composing the subapertures of the WFS. Although the use of laser guidestars may allow the substitution of faint source radiation with a bright artificial AO beacon, considerations of cost and complexity motivate a continuing interest in improving the detection sensitivity of a source referenced, low light level (LLL) WFS. This paper explores the promise of aluminum gallium arsenide/gallium arsenide (AlGaAs/GaAs) heterostructure photocathodes coupled to shot noise limited photon counting (PC) cameras and compares their performance with the read noise limited charge coupled device (CCD) cameras often used in this application. Figure (1) illustrates the quantum efficiency of the various detectors to be considered in the study, including two high performance AlGaAs/GaAs photocathodes recently obtained from Litton Electro-Optical Systems.
Fast CCD Imaging Systems for Tilt-Tip and Wavefront Sensing Applications
Authors: Mackay Craig D.
Published: February 2023

New generations of fast, low-noise CCDs and their controllers are achieving the read-out noise and high frame rates that are critical to the successful completion of true adaptive optics systems. We describe the performance achieved for a variety of systems from those on COAST (Cambridge Optical Aperture Synthesis Telescope), the site evaluation program on the William Herschel Telescope on La Palma, and the results from the latest fast CCDs and new generation of CCD controllers.
Scan–Hartmann Wavefront Sensor
Authors: Tartakovski Valeri A. , ukin Vladimir P.
Published: February 2023

Lomonosov and Descartes had known about the first principles of the Hartmann measurements. There are many references1 to a classical version of this method concerning testing the telescope optics. At the modern stage the Shack–Hartmann sensor is used.
High Resolution Adaptive System with a Phase Knife in the Optical Feedback Loop
Authors: Larichev A.V. , Nikolaev I.P. , Violino P.
Published: February 2023

Conventional adaptive systems, whose key elements are wavefront sensor and electromechanical wavefront corrector, face considerable difficulties, when high-order aberrations’ correction is required [1]. The increase of number of adaptive mirror’s control elements (up to several hundreds, recently [2]) inevitably leads to the sophistication of the sensor for measuring the wavefront “fine structure” and to intensive computations at the stage of wavefront reconstruction. Therefore, new techniques controlling light with light, which do not violate the distributed nature of light wave, attract attention of researchers [3, 4, 5]. There are a number of optically controllable hybrid devices (microchannel modulator [3], liquid crystal light valve (LCLV) [4], and membrane mirror [5]) that may be used for distributed wave front correction. However, the adequate control methods for such correctors should be developed.
Liquid crystal displays as programmable adaptive optical elements
Authors: Gregory Don A. , McClain John L. , Hudson Tracy D.
Published: February 2023

Most common optical elements employ some sort of phase delay in order to manipulate wavefronts. These optical elements (lenses, prisms, etc.) are well known and have fixed phase delays. Using a pixelated, phase modulating device, such as a liquid crystal television (LCTV), it is possible to design tunable lenses, prisms, and gratings.
Report on the optical quality of ADONIS* DM and relay optics: Is the Mirror Aging ?
Authors: Tighe R. , Prieto E.
Published: February 2023

November 1992 the Deformable Mirror (DM) for ESO's Near Infrared Adaptive Optics System (ADONIS), was delivered with a measured specification of surface flatness better than λ/2 without voltage applied on the actuators, and better than λ/4 when offset voltages are applied such that the first 8 Zemike terms are removed(1).
Combined Wavefront Sensor with Internal Reference Source: experimental study
Authors: Podoba Vladimir I. , Parfenov Vadim A. , Seregin Alexander G.
Published: February 2023

A wavefront sensor (WFS) is the key element of ground and space-based adaptive telescopes that provides a high accuracy and reliability of the operation of an adaptive mirror control system. We developed a new WFS in the scope of the project of a 3.2 m adaptive astronomical telescope with a wide angular field of view [1]. It has two parts - channels: an autocollimation-point sensor and interferometric (or Hartmann) one. The WFS is to be installed at the autocollimation point of low efficiency hologram structure on the controllable surface of the adaptive mirror [2]. Such a WFS combines two useful features: a high accuracy of interferometers and a wide angular range of operation in comparison with ordinary interferometers. Therefore, it provides the necessary information for initial alignment of the mirror and allows to diminish requirements to the rigidity of a telescope construction.
Models and measurements of atmospheric turbulence characteristics and their impact on AO design
Authors: Lukin Vladimir P.
Published: February 2023

1. DEVELOPMENT OF MODELS OF TURBULENCE SPECTRA Using the experimental data we would suggested to investigate behavior of spectral density of atmospheric turbulence in the region of large spatial scales. Special efforts will be done to detect the variability of large optical inhomogeneities as manifestation of the influence of thermodynamic instability of the atmosphere.
LiDAR-assisted accuracy improvement strategy for binocular visual measurement
Authors: Chen Junfeng , Bai Jingjing , Cheng Yunpeng , Ma Yunpeng , Li Qingwu
Published: February 2023

The measurement model of
binocular vision is inaccurate when the measurement distance is much
different from the calibration distance, which affects its
practicality. To tackle this challenge, we proposed what we believe to
be a novel LiDAR-assisted
accuracy improvement strategy for binocular visual measurement. First,
the 3D points cloud and 2D images were aligned by the
Perspective-n-Point (PNP) algorithm to realize calibration between
LiDAR and binocular camera. Then, we established a nonlinear
optimization function and proposed a depth-optimization strategy to
lessen the error of binocular depth. Finally, the size measurement
model of binocular vision based on the optimized depth is built to
verify the effectiveness of our strategy. The experimental results
show that our strategy can improve the depth accuracy compared to
three stereo matching methods. The mean error of binocular visual
measurement decreased from 33.46% to 1.70% at different distances.
This paper provides an effective strategy for improving the
measurement accuracy of binocular vision at different distances.
Inverse design of polarization conversion metasurfaces by deep neural networks
Authors: Chen Wanglei , Li Runkun , Huang Zetian , Wu Hao , Wei Jingyang , Wang Shu , Wang Le , Li Yanghui
Published: February 2023

To address the problem of multiple solutions and improve the calculating speed, we construct a tandem architecture consisting of a forward modeling network and an inverse design network. Using this combined network, we inversely design the circular polarization converter and analyze the effect of different design parameters on the prediction accuracy of the polarization conversion rate. The average mean square error of the circular polarization converter is 0.00121 at an average prediction time of 1.56×10−2s. If only the forward modeling process is considered, it takes 6.15×10−4s, which is 2.1×105 times faster than that using the traditional numerical full-wave simulation method. By slightly resizing the network input and output layers, the network is adaptable to the design of both the linear cross-polarization and linear-to-circular polarization converters.
Parallel unambiguous generalized phase-shifting and T-spline fitting algorithms for optical micro-structured surface 3D topography metrology
Authors: Duan Yiting , Zhang Xiaodong
Published: February 2023

3D topography metrology of optical micro-structured surfaces is critical for controlled manufacturing and evaluation of optical properties. Coherence scanning interferometry technology has significant advantages for measuring optical micro-structured surfaces. However, the current research faces difficulties of designing high accuracy and efficient phase shifting, and characterization algorithms for optical micro-structured surface 3D topography metrology. In this paper, parallel unambiguous generalized phase-shifting and T-spline fitting algorithms are proposed. To avoid phase ambiguity and improve the accuracy of the phase-shifting algorithm, the zero-order fringe is determined by the iterative envelope fitting with Newton’s method, and the accurate zero optical path difference is determined by a generalized phase-shifting algorithm. In particular, the calculation procedures of the multithreading iterative envelope fitting with Newton’s method and generalized phase shifting are optimized with the graphics processing unit-Compute Unified Device Architecture kernel function. Additionally, to fit the base form of optical micro-structured surfaces and characterize the surface texture and roughness, an effective T-spline fitting algorithm is proposed by optimizing the preimage of the T-mesh with image quadtree decomposition. Experimental results show that the surface reconstruction of optical micro-structured surfaces using the proposed algorithm is more accurate, and the efficiency is 10 times higher than that of current algorithms; the time of the surface reconstruction is less than 1 s. Compared with the current B-spline method, the accuracy of roughness characterization using the proposed T-spline algorithm is improved by more than 10%.