bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcomes following external beam radiotherapy to the prostate and pelvic lymph nodes in addition to androgen deprivation therapy in non-metastatic prostate adenocarcinoma with regional lymph node involvement: a retrospective cohort study
Authors: Mohamad Roji Akmal , Sandhu Rahul , Zarkar Anjali
Published: February 2023

Objective

There is a paucity of evidence for external beam radiotherapy (EBRT) in patients with non-metastatic prostate adenocarcinoma with regional lymph nodes (cN1) as primary treatment in addition to androgen deprivation therapy (ADT). We present the retrospective outcomes of cN1 patients treated with prostate and pelvic nodal (PPLN) EBRT and ADT.

Methods

The clinical records of cN1 patients given PPLN EBRT from January 2012 to January 2020 were retrospectively reviewed. Primary outcomes of overall survival, prostate cancer-specific survival, and failure-free survival were analysed. Secondary outcomes of biochemical relapse-free survival, locoregional recurrence-free survival, and distant metastases-free survival were also reviewed. The prognostic values of clinicopathological parameters were investigated. Treatment toxicity was also reviewed.

Results

We identified 121 cN1 patients treated with PPLN EBRT and ADT. Treatment was well tolerated, with only a minority (1.7%) having Grade 3 toxicities. 5-year overall survival and prostate cancer-specific survival were 74.4 and 89.1% respectively. 5-year failure-free survival was 55.4%; with 5-year biochemical relapse-free survival, locoregional recurrence-free survival, and distant metastases-free survival at 56.2%, 85.2%, and 65.4% respectively. The benefits of PPLN EBRT were seen in most patients, with prolonged failure-free period and good loco-regional control.

Conclusion

Patients with cN1 disease should be considered for PPLN EBRT, in addition to ADT. Treatment is well tolerated with low toxicity, good locoregional control, and prolonged time to disease progression.

Advances in knowledge

We report real-world experience of cN1 patients treated with PPLN EBRT in addition to ADT, with good outcomes following treatment and low toxicity.
Business planning: a workshop using the Project Expert program
Authors: Aliev Vagif , Kononenko A.F. , Ross G.V.
Published: February 2023

The tutorial uses practical examples to describe the technology of developing and analyzing acceptable investment projects, as well as the process of creating business plans for these projects using the popular Project Expert 7 program.
The issues of computer implementation of financial management elements in the MS Excel PPP environment related to investment design are considered.
To understand the methods used in the Project Expert 7 program, the issues of calculating performance indicators and financial indicators of investment projects using MS Excel PPP using financial reporting tables that are automatically created by the Project Expert 7 program are studied. The risks of investment projects in the MS Excel PPP environment are analyzed.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
It is intended for students studying in the field of Economics and Management; teachers and postgraduates of economic universities; heads of enterprises, organizations and firms involved in the preparation of expertise and implementation of business plans, including for advanced training courses in the direction of "Development and analysis of investment projects using modern information technologies".
Strategic management in the hotel and restaurant service.
Authors: Krupina Nadezhda , Moskalev Mihail , Omarov Magomed
Published: February 2023

The textbook is structured on topics that are relevant in the practice of strategic management at modern enterprises of the hospitality industry and for the formation of professional competencies of students in the direction of "Service".
A wide range of theoretical issues, factual data and illustrative materials are presented, which reveal the nature and essential content of the strategy, strategic management, develop ideas about the organizational environment and methods of its qualified analysis, form skills of strategic planning, development, formalization, implementation and evaluation of the effectiveness of the chosen strategy, taking into account the peculiarities of production in hotel and restaurant complexes. Each topic ends with a variety of tasks for self-examination and self-control of the quality of assimilation of the material.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
For those who want to increase the level of knowledge and understanding of strategic management in the hotel and restaurant business, to develop practical skills of strategic analysis and planning.
The legal regime of lands and its regulation
Authors: Lipski Stanislav , Muhlynina Mariya , Cypkin Yuriy
Published: February 2023

The textbook describes the essence of the legal regime of lands and the ways to ensure its observance by the participants of land legal relations. The general characteristics of land plots and the land fund as a whole are given, its composition is considered (by target categories, land and forms of ownership). The features of the legal regime of all seven target categories of land provided for by the current legislation, as well as the main tools for its provision are disclosed: land supervision and land control, monitoring of the use and condition of land, their transfer to another category, etc. Attention is paid to bringing to responsibility for non-compliance with the legal regime established for lands and land plots. In addition, an overview of domestic (pre-revolutionary, Soviet, early post-Soviet) and modern foreign experience in determining the legal regime of lands is provided.
The study of the presented material will allow you to master the competencies provided for by the relevant educational standard and form a systematic perception of the legal regime of lands established in accordance with the legislation and the ways of its regulation among students.
Complies with the federal state educational standards of secondary vocational education of the latest generation.
For students of secondary vocational education institutions studying in the specialty 21.02.04 "Land management".
Antimonopoly and tariff regulation in the system of state control of the Russian Federation
Authors: Korolev Vitaliy , Berdnikov Dmitriy , Geller Aleksandr , Kirillova Oksana , Vasin Sergey , Kirillov Roman , Kapitonov Ivan , Gavrilenko Dmitriy , Orlova Lyubov' , Filimonenko Anna , Antonov Viktor
Published: February 2023

The textbook extensively covers the most pressing issues of antimonopoly and tariff regulation.
The basics of antimonopoly and tariff regulation are outlined, the main activities of the Federal Antimonopoly Service as a state regulator, its functions, powers and responsibilities in the implementation of state antimonopoly control and tariff policy, as well as issues of sectoral tariff regulation and control over economic concentration are considered.
Separate chapters are devoted to: types of unfair advertising and measures of responsibility for its placement; control of procurement activities. Various approaches to assessing the prospects for the development of corporations in a competitive environment are presented, for example, PPP, which, on the one hand, acts as a development tool, and on the other — as an object of antimonopoly regulation. The essence of the antimonopoly compliance method, which is used to prevent regulatory risks, is disclosed.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
For students studying in the areas of training "Management" and "Jurisprudence" (bachelor's and master's levels), studying issues of competition, antimonopoly control and tariff policy from the point of view of management in these areas.
Consideration of disputes arising from land legal relations. Workshop
Authors: Pozdnyakova Elena , Tarnavskiy Oleg , Bogolyubov Sergey , Nahratov Vitaliy
Published: February 2023

The workshop is designed to assist students in mastering the discipline "Consideration of disputes arising from land legal relations". The course is a complex discipline, the content of which includes the norms of previously studied disciplines. This publication allows you to consolidate the theoretical knowledge of students by conducting seminars, solving tests, tasks on them, as well as listening to reports. To help students prepare for classes and pass the test, a list of regulatory legal acts, judicial practice and relevant literature is provided.
Meets the requirements of the federal state educational standards of higher education of the latest generation.
For students of higher educational institutions studying in legal fields, as well as teachers.
Sources and forms of law in modern financial and legal science
Authors: Peshkova (Belogorceva) , Miroshnik Svetlana , Zapol'skiy Sergey , Shohin Sergey , Kudryashova Ekaterina , Belikov Evgeniy , Ivanyuzhenko Andrey , Karcov Aleksey , Komyagin Dmitriy , Bochkareva Ekaterina , Evsikova Elena , Reut Anna
Published: February 2023

The monograph is devoted to the most urgent problems of the theory of sources and forms of financial law that require a new understanding in modern legal reality. The work was prepared by well-known scientists in the field of financial law science.
Special attention is paid to the content and limits of constitutional regulation of financial legal relations, constitutional norm control, the history of the formation of forms and sources of financial law, methodologically significant categories of financial law.
The problems of establishing legal institutions and sub—branches of financial law, as well as complex legal entities - banking law, insurance law, currency law - in regulatory legal acts are investigated.
The issues of formation of sources of legal regulation of money circulation and settlements, banking activities are considered.
The issues of sources of international financial law are revealed and the correlation of national and international financial and legal regulation is determined.
It is intended for researchers of research organizations, university professors, practitioners, students of law and financial universities, as well as anyone interested in the subject of financial and legal science.
Genetic research: legal and ethical aspects
Authors: Rustambekov Islambek , Madreymova Asem , Gulyamov Said , Narziev Otabek , Bozarov Sardor
Published: February 2023

The monograph discusses the theory and legal regulation of genetic research on gene editing, the use of stem cells in medicine, as well as biotechnology.
It is the first publication on legal issues of genetic engineering in the Republic of Uzbekistan.
For undergraduates, researchers and teachers of law schools and faculties of other educational institutions specializing in the field of law.
ESG export project support tools based on international experience
Authors: Perskaya Viktoriya , Starodubceva Elena , Homyakova Lyubov' , Mamedov Tural , Rybakov Vitaliy , Zvereva Aleksandra , Chizhova Alina , Ogryzov Andrey
Published: February 2023

The monograph presents a toolkit for supporting export-oriented ESG projects and complete capital construction facilities for industrial and social purposes based on compliance with the principles of ESG, its applicability to support export-oriented projects in the context of the goals and objectives of the foreign economic policy of the Russian Federation.
It can be useful in the implementation of international development assistance programs, as well as in the educational process of bachelors and undergraduates and in the research work of postgraduates and doctoral students.
Management of the development of a high-tech industrial complex
Authors: Daneykin Yuriy , Doroshenko Yuriy , Erznkyan Bagrat , Tumin Valeriy
Published: February 2023

The monograph is devoted to topical issues of managing the development of high-tech industrial complexes in order to achieve technological sovereignty of the Russian Federation. The author's concept of managing the development of a high-tech industrial complex at the meso-level is presented, the issues of assessing the contribution of innovative ecosystems and high-tech industrial complexes to the development of the region are highlighted. Special attention is paid to innovative scientific and technological centers in achieving the goals of innovative and technological development of industry. The role of INTC "Intelligent Electronics — Valdai" in the development of the electronic industry and the Novgorod region is considered on a specific material. Methodological provisions for the classification of innovative behavior of electronic industry enterprises, a matrix of models of innovative behavior of industry enterprises have been formed.
For specialists in the field of management, researchers, teachers and university students of specialized areas of training.
Replacement of Missing Anterior with Maryland Bridge using Ribbond: A Case Report
Authors: Sharma Anjali , Motwani Rashi , Singh Santosh Kumar , Mishra Pankaj , Narang Anu
Published: February 2023

Replacement of missing mandibular central incisor is difficult challenge in esthetic dentistry. Resin bonded bridges or maryland bridges can be considered as a treatment of choice in such conditions, which restore the oral function and esthetic of the patient. Maryland bridge preparation requires minimal preparation of the tooth and the bridge can be attached to the periodontally sound adjacent teeth.The combined use of polyethylene fibre and resin composite help achieve durable and functional result.This case report describes the case of esthetic restoration of a young women with midline spacing of mandibular anterior teeth.
Spectral Sensitivity and Light Adaptation in Primate Photoreceptors
Authors: Schnapf J. L. , Kraft T. W. , Baylor D.A.
Published: February 2023

For a complete description of the mechanisms underlying human color vision it is obviously necessary to include the spectral absorption properties of human photoreceptors. We have determined the action spectra of human rods and cones by recording the photocurrent.
Adaptation of human cone receptors: Recordings of cone a-waves
Authors: Hood Donald C. , Birch David G.
Published: February 2023

Boynton and Whitten1 were the first to attempt a quantitative description of the physiology of of primate cone adaptation. Using Brown's technique2 to isolate the summed receptor potential responsible for the cone a-wave of the monkey's ERG, they concluded that substantial adaptation occurred at the level of the cone receptor. The amount of adaptation and the mechanisms involved, however, are still open to debate. Here we focus on the mechanisms of adaptation of human cone receptors.
Isolation of Color Mechanisms Using a Silent-Substitution Method
Authors: Van Toi Vo , Burckhardt C.W. , Grounauer P.A.
Published: February 2023

In an investigation of the temporal modulation transfer function (De Lange curve), Kelly found three peaks instead of one and suggested that these peaks are related to the three mechanisms B, G, and R of color vision (ref 1). Although the existence of these peaks was statistically confirmed it is still unclear whether they relate to the color mechanisms (ref 2). If this relation does exist at least two facts would be proved: (a) the De Lange curve of each isolated mechanism should have only one peak and (b) these peaks should be located at 5, 10 and 20 Hz respectively.
Individual differences in rayleigh matches are related to differences in L cone pigment structure
Authors: Lindsey Delwin T. , Winderickx Joris , Sanocki Elizabeth , Teller Davida , Deeb Samir S. , Motulsky Arno G.
Published: February 2023

Our study was concerned with the molecular basis of psychophysically-established individual differences in L cone photopigment absorption spectra. We approached the question from two different but related directions and obtained converging results. The first approach was to compare L pigment gene structure with Rayleigh matches in a group (N=50) of color normal males. The second was to compare Nagel anomaloscope intensity settings in deuteranopes (N=10) who, by molecular analysis, were shown to have only a single L pigment gene. Prior signed consent was required of subjects who participated in either study.
Contrast Sensitivity for Isoluminant and Isochromatic Interference Fringes
Authors: Sekiguchi Nobutoshi , Williams David R.
Published: February 2023

There has been recent interest in comparing the efficiency with which chromatic and luminance information is processed in the visual system. This comparison has been made with many different tasks including spatial and temporal contrast sensitivity, stereopsis, motion, and vernier acuity. Performance is generally worse for isoluminant than isochromatic stimuli, which has led to the view that chromatic information is processed less efficiently than luminance information. However, the overlap in the spectral sensitivity of cones limits the the highest contrast that can be realized in the L and M cones with isoluminant stimuli, a limitation that does not apply to isochromatic gratings. We sought to determine how much of the difference between contrast sensitivity for isoluminant and isochromatic stimuli can be attributed to this overlap and how much to post-receptoral factors. It is well established that isoluminant and isochromatic contrast sensitivity differ at low spatial frequencies due to the presence of a low-frequency cut for isochromatic stimuli Our interest was to determine whether the performance at high spatial frequencies is also different.
Relative abundance of the cone types: Analysis of absolute threshold evidence
Authors: Tyler Christopher W. , Liu Lei
Published: February 2023

The relative number of the R (or long-wavelength-sensitive) and G (or middle-wavelength-sensitive) cone types in human retina is not known, since no differential histological stain has been developed for human or any other species. A cumulation of evidence from indirect studies summarized in Vimal et al. (1989) suggests that there may be about twice as many R cones as G cones in human fovea. In particular, the additive model of Smith and Pokorny (1975) with their R and G fundamentals derived from the photometric Vλ function (solid circles) is shown in Fig. 1A. However, those studies were all conducted under light-adapted conditions, where various suprathreshold influences and nonlinearities may have contaminated the results (e.g. Boynton and Whitten, 1970; Guth, 1991). Moreover, at least one of the studies (Rushton and Baker, 1964) was based on flicker photometric matches at high frequency, which we have shown to be contaminated by different temporal properties of the R and G cone systems (Hamer and Tyler, submitted). Moreover, Guth’s (1991) current version of his "vector model" requires the initial weights of the R to G mechanisms to be 0.66:1 rather than 2:1. Although Guth disavows any implication for receptor densities, it is important to note that this rather complete model disagrees with the other evidence under the same assumptions about the relation between psychophysical sensitivity and cone densities.
Color processing in visual cortex
Authors: Gilbert Charles
Published: February 2023

Wavelength specific cells in visual cortex are grouped together into compartments that are interdigitated between other compartments specializing in form, movement and depth. The first evidence for a functional organization of color based on cortical area came from the work of Semir Zeki, who described an area prestriate cortex, known as area V4, that was enriched for color specific cells. Other cortical areas also contained wavelength selective cells, but the precise distribution of these cells eluded investigators for a number of years until the discovery by Margaret Wong- Riley that in area VI the enzyme cytochrome oxidase (CO) was distributed in a regular series of patches, as seen in tangential sections through the superficial cortical layers. Using CO histochemistry, David Hubei and Margaret Livingstone found that wavelength selective cells were located within these patches or "blobs", with broadband, orientation selective cells being found predominantly outside them. This lent support to the idea that color, as represented by wavelength selective cells, and form, as represented by orientation selective cells, were analyzed by separate, parallel pathways in the visual system. This left open, however, the question of how information about form and color might be attributed to a particular object, the so called "binding" problem, and also about how boundaries made by different colors could provide information about form. In fact, the existence of cells selective both for wavelength and for orientation had been known from a number of studies, and Ts'o and Gilbert found that such cells tended to lie at the boundaries of the CO blobs. With regard to the color selectivity found within the blobs, they found that cells sharing similar color opponency were grouped into columns, and that individual blobs specialized in either red-green or blue-yellow opponency.
Equivalent Lightness of Colored Charts at Various Illuminance Levels
Authors: Ikeda Mitsuo
Published: February 2023

When a gray object and a colored object are equated in their lightness as defined by, for example, L* in the CIE l976L*u*v* system, and observed side by side, the colored object looks always brighter than that of gray. A need arises for a new concept, equivalent lightness for these objects so that when both objects are equated in the equivalent lightness, they look equally bright. Equivalent lightness of an object may be defined as the lightness of a gray scale that matches with the colored object in brightness. We have experimentally determined the equivalent lightness of various colored charts at various illuminance levels including scotopic, mesopic and photopic levels to understand the underlying mechanism for brightness perception of colored objects.
Quasi - Mechanistic Accounts of Color Constancy
Authors: MacLeod Donald I.A.
Published: February 2023

We can perceive the lightness and color of surfaces fairly accurately despite large variations in the intensity and spectral composition of the illumination. This color constancy is a form of visual adaptation in a general sense. But it is a different aspect of light adaptation--the associated change in visual sensitivity--that has been most completely documented in psychophysical and physiological experiments, and it is not yet clear to what extent the phenomena of constancy can be traced to the operation of known or plausible sensitivity regulating processes in the visual system. This paper will present an analysis of some of the evidence bearing on that issue.
Chromatic Adaptation and Color Constancy
Authors: Fairchild Mark D.
Published: February 2023

The spectral power distribution reaching the eye from an object varies with the spectral output of the illumination source and the spectral reflectance of the object. If color vision is to serve in the identification of objects, it is desirable to have a system that responds to the spectral reflectance of the object, a stable attribute, independent of the spectral characteristics of the illumination. The significant stability of object color appearance despite changes in illumination conditions is commonly referred to as color constancy.
Color Constancy
Authors: Reeves Adam , Arend Lawrence E
Published: February 2023

We have investigated the extent of color constancy in complex (Mondrian) and simple (center-surround) displays. Our critical finding is that the extent of lightness and color constancy in such displays depend heavily on the instructions given to subjects. We also find, not surprisingly, that adaptation has a powerful effect on color constancy. Stimulus conditions, particularly spatial complexity, which have been thought critical in lightness and color constancy, however have little or no effect. This is true for judgments made with successive as well as with simultaneous displays.
Brightness-to-Luminance Ratio, Saturation, and Hue of Colored Lights
Authors: Ayama Miyoshi , Ikeda Mitsuo
Published: February 2023

It is well known that luminance of colored light is not always equal to that of a given reference light in the heterochromatic brightness matching. A number of studies have shown this brightness-luminance discrepancy with various experimental conditions, however, only a few studies have measured the amount of the discrepancy, using a field size of about 2 degrees, for a large number of test stimuli sampled systematically in a wide region of the chromaticity diagram [1-3]. Therefore, in the present study, we used 195 test stimuli distributed uniformly in the whole area of the CIE 1976 (u',v') chromaticity diagram. We measured the luminances (L) of these lights that appeared equally bright as the achromatic reference light with a fixed luminance (B), and determined the brightness-to- luminance ratios, the B/L ratios, for the stimuli. Simultaneously, we measured perceived saturation and hue of the test stimuli to investigate how the B/L ratio is related to the saturation and hue.
Application of the Single-hue Naming Method to the Determination of Elemental Hues
Authors: Miller David L. , Wooten Bill R.
Published: February 2023

Elemental (unique) hues are those which cannot be perceptually analyzed into more basic hue components, and thus cannot be further described by other hue names. The most popular method for investigating the appearance of elemental hues is the method of Stemheim and Boynton (1966). In this method observers are given a set of hue terms with which to describe spectral lights. If a hue term is both necessary and sufficient to describe a stimulus, the hue is determined to be elemental.
On increments-decrement differences in multiplicative gain control
Authors: Mausfeld Rainer J. , Niederée Reinhard M.
Published: February 2023

Center-surround stimuli evoke color appearances resembling surface colors which cannot be produced by a single homogeneous spot of light alone (e.g. brown, grey). Although this seems of great impact to a general theory of color (incl. color constancy), the psychophysics of these ‘minimal relational stimuli’ is still less well understood than often assumed. On the basis of empirical as well as theoretical observations concerning center-surround-type stimuli we introduce a relational model of color coding. The proposed model takes into account results on “discounting the background” mechanisms by Whittle, Walraven and Shevell and it is closely related to ratio-based relational concepts (Wallach, Land) and certain opponent color theories. Comprising the Young-Helmholtz, respectively Grassmann theory of color vision as a special case, this model provides an analogue to the classical distinction between light and object colors as well.
Readability Of Colored Tele-Texts And Visual Color Responses Of The Aged And The Young At Different Viewing Distances
Authors: Hasegawa Takashi , Kadowaki Miyuki
Published: February 2023

In order to recommend preferable color-sets of low luminance contrast in tele-texts, four elder subjects (61-65 years old) and four young subjects (21-22) subjectively evaluated readability of texts at two different viewing distances (6H and 12H, H: picture height) and psychophysical tests were conducted of their color discrimination, luminosity function (non-spectral) and spatial frequency function (brightness).
Psychological Evaluation of the Colored Pictures
Authors: Takeichi Keishiro
Published: February 2023

The purpose of this study is to see psychological effects of colored pictures in art and nature. Semantic differential method was employed for this evaluation to extract possible evaluation components.
On the Possibility of Visually Significant Intraocular Photoluminescence
Authors: Kandel Gillray L. , Eklund Neil H. , Schroeder John
Published: February 2023

Photoluminescence (PHL) of the human lens in vitro is well documented in the biochemistry literature (for a review, see Bloemendal, 1978 ). This PHL has been independently confirmed in our laboratories in in vitro human lenses.
Perception of translucent colors with binocular parallax
Authors: Okajima Katsunori , Takase Masanori , Takahashi Sumio
Published: February 2023

There are some kinds of color appearance mode: luminous color mode, surface color mode and so on. Translucent color mode is also a kind of them. For example, when we look a colored object or a colored light through a frosted glass, we perceive a translucent color. In this mode, it is different from other modes that a plural color perception is caused by visual system. Therefore it is suggested that translucent perception relates to functions of higher level in color vision. The purpose of this work is to analyze the mechanism of translucent perception by simulating translucent colors with binocular parallax.
Categorical Characteristics of Color Discrimination in Memory
Authors: Uchikawa Keiji
Published: February 2023

Colors can be systematically represented, based on their appearance, in a three-dimensional color space. They change continuously in any direction in the color apace so that we could discriminate a million of colors when two color are simultaneously compared in juxtaposed fields. It is unlikely, however, that we can utilize so many colors in our everyday situations where some color memory seems to be necessarily involved.1-5 Color appearance may not be precisely retained in memory, and colors may be categorically organized in memory.6,7,8 In the present paper, I will focus on color discrimination or identification tasks using memory. Some of our recent studies, which indicate categorical influences on color discrimination in memory, are described here.
The Constancy of Equiluminant Red-Green Thresholds Examined in Two Color Spaces
Authors: Eskew Rhea T. , Stromeyer Charles F. , Kronauer Richard E.
Published: February 2023

Chromatic detection by the L or long-wavelength cones and M or middle-wavelength cones can be conveniently represented in the diagram shown in Fig. 1. The vertical axis represents the change in the quantal catch of the M cones, produced by a test light modulation, divided by the quantal catch in the M cones produced by all of the steady field components. The horizontal axis represents the analogous quantity for the L cones. Fig. 2 shows the simple model which justifies this representation. The cone classes adapt independently of one another before being combined into the red-green chromatic and luminance mechanisms. The model requires that adaptation take place within each cone pathway, but not necessarily in the cones themselves. Adaptation also occurs at the opponent stage. The linear combinations of cone contrasts shown in the model of Fig. 2 imply that detection contours in cone contrast space should be four straight line segments (only three of which are shown in Fig. 1). Each vector in Fig. 1 represents the threshold for a particular ratio of red to green light modulations, corresponding to a particular ratio of L-to-M cone modulations. The 45° vector represents a test stimulus with the same chromaticity as the adapting field. If there is a detection mechanism which combines cone contrasts linearly and has a response which is independent of luminance modulation, it must have a detection contour which is parallel to the 45° line - that is, it must have a slope of +1.0 — regardless of the adapting chromaticity. No such simple constraint governs the slope of the luminance detection contour. The 45°-225° direction will be here referred to as the “equichromatic” direction.
Minimally Distinct Border: 1824 -1990 A Tribute to RMB
Authors: Kaiser Peter K.
Published: February 2023

Although the distinctness of a border was already used by Fraunhofer as a visual photometric criterion in 18241, it is only during the last 25 years that it has been extensively used and explored.
Luminance is the intensity dimension of shading
Authors: Shioiri Satoshi , Sunaga Shoji , Kubo Soichi
Published: February 2023

Luminance, which is measured by the heterochromatic flicker photometry with high-temporal frequency stimuli, is often referred as the intensity dimension of the achromatic form pathway. This is supported by the fact that sharpness of the edges is minimized at isoluminance as has been suggested by minimally distinctness border (MDB) experiments. On the other hand, brightness measured by direct brightness matchings is another intensity dimension for an achromatic process. It may be that brightness is the achromatic dimension for low-spatial and low-temporal frequency domain while luminance is that for high-spatial and high-temporal frequency domain. However, there are two reports that suggest that luminance controls achromatic form perception in relatively lower spatial and temporal frequency stimuli; i.e. the strength of blurred edges 1), subjective contours2) and shadows2) is minimized at isoluminance. We used shading figure in two colors (Fig. 1) whose spatial frequency was controlled by the slope of the gradual luminance change. The iso-achromatic point could be measured by the relative luminance at which the impression of shading was minimized or disappeared completely.
Short-Exposure Measurements of Anisoplanatism using Binary Stars
Authors: Ellerbroek Brent L. , Christou Julian C. , Riker James F. , Roark J. Timothy
Published: February 2023

The compensated field-of-view of a ground-based adaptive-optics system is limited because the phase distortions introduced by atmospheric turbulence vary with the direction of the source. This effect is referred to as anisoplanatism. More specifically, tilt anisoplanatism denotes the differential image motion of two separated point sources observed through a common aperture, while higher-order anisoplanatism refers to variations between the shapes of the two point spread functions. Previous long-exposure observations of a multiple star system [1] have measured the combined effect of these two degradations upon the imaging performance of an adaptive-optics system, but the individual values of these two separate error sources have never been independantly determined. Such measurements would provide a sharper test for theoretical models of anisoplanatic effects, and enable sky coverage calculations for laser guide star adaptive-optics systems to be based upon measured data.
Low Order Adaptive Optics at the Anglo-Australian Telescope
Authors: O’Byrne J. W. , Bryant J. J. , Minard R. A. , Fekete P. W. , Cram L. E.
Published: February 2023

The adaptive optics (AO) project at the Anglo-Australian Telescope (AAT) is sponsored by a consortium of Australian universities and the Anglo-Australian Observatory (AAO) and funded by the Australian Research Council (ARC). The program has two objectives: 1. to prove the usefulness of adaptive optics at the AAT site, and 2. to rapidly implement an adaptive system, providing a scientifically valuable gain in the resolution and efficiency of the telescope.
The 6.5 m MMT Infrared Adaptive Optics System: Detailed Design and Progress Report
Authors: Sandler D. G. , Lloyd-Hart M. , Gray P. , Martinez T. , Angel R. , Barrett T. , Bruns D. , Stahl S.
Published: February 2023

In late 1996, the Multiple Mirror Telescope will be replaced by a 6.5 m telescope with a single borosilicate honeycomb primary mirror. Earlier we showed [1] that an adaptive optics system using a low-power sodium laser guide star could provide diffraction-limited performance for infrared imaging in H and K bands, yielding the equivalent 0.05 arcsec resolution of Hubble Space Telescope optical images over most of the sky. Our approach used a continuous-wave sodium dye laser of a few watts, projected from a flat above the secondary mirror. To yield the highest efficiency and lowest emissivity, we proposed using an adaptive secondary mirror for full correction of the wavefront. In addition, the use of an infrared field star sensor to sense the global atmospheric tilt was shown to give very good sky coverage. A schematic of the system concept for the 6.5 m MMT is shown in Fig. 1.
The Potential Accuracy of Segmented Mirror Figure Stabilisation with Two-Stage Testing
Authors: Sidorov Victor I.
Published: February 2023

The set of two independent testing subsystem of segmented mirror figure based on heterodine interferometer and local sensors of angle and linear moving makes it possible to solve the 2nπ problem and reduce demands to the stability of local sensors zero point.
ADONIS Disclosure of Ultracompact HII Regions
Authors: Stecklum B. , Hayward T. L. , Feldt M. , Löwe M.
Published: February 2023

Near-infrared adaptive optics observations of the ultracompact HII region G45.45+0.06 using ADONIS revealed a compact star cluster at this site of massive star formation.
Performance Test of the slow Wavefront Sensor for the Large Earthbased Solar Telescope LEST
Authors: Owner-Petersen Mette , Jensen Michael , Engvold Oddbjørn
Published: February 2023

The LEST wavefront sensor described here is intended for control of the aberrations induced by slow variations in the mechanical structure of the telescope. Hence the effects of atmospherical fluctuations must be averaged out. Active control of LEST based on the sensor signals will be performed tilting the main mirror M1 (eliminating misalignment coma), translating M3 (eliminating defocus) and adjusting the supports of the active M1 (modal compensation of other aberrations). The sensor works according to the Shack-Hartmann principle. Hartmann shifts are determined from a least squares estimate of the slope of the cross correlation spatially spectral phase. The algorithm adapts automatically to the actual spectral content of the subimages, ie to both object structure and seeing conditions.
Characterization of the Wavefront Produced by a Two-Dimensional Spatial Liquid Opto-Electronical Light Modulator*
Authors: Bourimborde Lea V. , Zerbino Lía M. , Aguirre Eduardo , Liquidara Anibal P. , Garavaglia Mario
Published: February 2023

The characterization of the wavefront produced by a two-dimensional spatial liquid opto-electronical light modulator was made by simple diffraction and interference experiments. The electrical video signal is injected in the thin oil film by an electron gun as in a CRT. This signal contains both the RGB carriers and their modulations. The electron activated area of the liquid opto-dectronical device is illuminated by a xenon arc discharge lamp. To get an uniform illumination on that area, the light from the lamp is refracted in two lenticular plates. The thin oil film is located between the grids of a schlieren optical system. Then, the video signal injected in the active area is projected onto a screen by a projection lens. By varying the illumination of the active area and the schlieren and projection optical systems, it is possible to select appropriate experimental conditions to determine the coherence of the light emitted by the liquid opto-electronical device. Then, very interesting interferential and diffractive experiences can be performed in order to test the ability of the device to project computer synthetic wavefronts.
Liquid Crystal over VLSI Silicon Spatial Light Modulators for Adaptive Optics
Authors: Gourlay J. , O’Hara A. , Vass D.G.
Published: February 2023

Liquid Crystal (LC) over Very Large Scale Integration (VLSI) electrically addressed reflective Spatial Light Modulators (SLM) have been identified as very powerful, combining the very attractive features of both the LC and VLSI technologies [1]. LC has very low power requirements for high optical modulation effects and VLSI can allow high yield and compact modulators with a high level of functionality on-chip. The device has an LC cell fabricated on top of a custom designed VLSI silicon backplane (see figure 1). The backplane contains an array of pixel memory elements, pixel mirrors and addressing circuitry. The controllable pixels in the SLM can switch the liquid crystal to achieve modulation. A number of these devices have been developed and demonstrated in a variety of optical systems such as compact displays [2], optical correlators [3] and as reconfigurable holograms [4]. A constructed SLM device in a standard chip package is shown in figure 2. In this example, the chip in the center is 1cm2 (the package itself is ≈ 3 × 3 cm2.
Bispectral Imaging Toolbox
Authors: Negrete-Regagnon Pedro
Published: February 2023

For centuries, astronomers have built larger telescopes attempting to collect more light so fainter objects could be studied, but resigned to the fact that such larger telescopes would not provide higher resolution. It was until 1970, when Antoine Labeyrie notice the significant difference between short-exposure and the long-exposure images astronomers were used to see. Labeyrie reasoned that each speckle present in the short-exposure image was actually a diffraction-limited image formed by the telescope. He concluded that a short-exposure image contains high resolution information not present in the long-exposure counterpart, and invented a method to extract such high resolution information that is termed speckle interferometry.
Fractional moments for investigating laser atmospheric scintillation statistics
Authors: Consortini A. , Rigal F. , Cochetti F.
Published: February 2023

The problem is the determination of the probability density function of intensity fluctuations from experimental data of laser propagation through atmospheric turbulence. The proposed solution is very general and appears to be applicable to any statistical problem.
The algorithms for measurement of displacement of white-light fringes
Authors: Butenko Lev N. , Seregin Alexander G. , Fridman Peter A.
Published: February 2023

A white-light source is used so that good interference occurs only when
the two paths are equal, that is, when both primary mirror’s segments
are the same distance away from the interferometer, e.g. with a
double-image prism in the adaptive telescope. When observing a
small step between surfaces with comparable reference dimensions,
interference fringes are usually formed in white light that are
perpendicular to the boundary line between the surfaces. An
interferometer with white-light source is based on a prism design
that includes a rectangular prism with a beamspliter hypotenuse face
to which an additional prism is cemented to form a double-image
compound pentaprism. It makes possible to monitor the step between the
elements of a compound primary mirror more simply than in an
interferometer with Kosters prism. This is because of the almost
complete compensation of the optical path length in a system with
counterpropagation of the interfering beams. Preliminary phasing of
primary mirror segments during assembling process may be accomplished
with help of a such ambiguity sensor. The experimental investigations
with visual control showed a possibility to recognize displacement of
1/20 wavelength. This investigation was fulfilled at the special test
bench with high resolution laser interferometer. The interferometer
resolution is 1 nm.
One-channel deformable mirrors for low-order adaptive optical compensation
Authors: Safronov Andrei G.
Published: February 2023

The adaptive optics for low order correction, the so-called "small" adaptive optics, is of particular actuality and interest because of its simplicity and low cost. The present paper is dedicated to one-channel deformable mirrors designed for use in above mentioned systems including industrial ones.
Test and analysis of low-light characterisation of the ICCD Hartmann-Shack wavefront sensor
Authors: Zhang Qiang , Xu Bing , Chen Li
Published: February 2023

Hartmann-Shack wavefront sensors (Hartmann WFS) are widely used for optical wavefront measurement in adaptive optics. They are especially useful in the conjunction with laser guide stars that provide a quasi-point-source reference with continuous and pulse operating patterns. The principle of the sensor is that an array of lenslets is used to divide the coming wavefront into subaperatures and form images at their focal planes where the detector is placed. If the wavefront is plane, each lenslet forms an image of the source at its focus. If the wavefront is disturbed, each lenslet receives a tilted wavefront and forms an image out of axis in its focal plane. The measure of the image position gives the angle of arrival of the wave for each lenslet. The Hartmann WFS generally consists of a lenslet array, a detector which is a CCD or an intensified CCD, and an image processing system. For both natural and guide stars, a very low-light photo-counting level characterisation of the sensor is needed. And the knowledge on the low-light performance of the sensor for the both operating patterns is useful for the AO system design.
Atmosphere Potentialities of the Methods of the Posteriory Processing of Incoherently Illuminated Objects through the Turbulent
Authors: Lukin Igor P.
Published: February 2023

Optical transfer function (OTF) and the integral resolution of the optical system "turbulent atmosphere - telescope" are treated theoretically by different methods of posteriory processing of incoherently illuminated objects observed through the turbulent atmosphere. The following processing methods are examined: the averaged image recording ("very long" averaging times) and short-exposure images ("very short" averaging times), namely, Labeyrie, Knox-Thompson, and triple correlation of image intensity methods. The influence of the finite value of the turbulent atmosphere outer and inner scales on the OTF's under consideration is also estimated.
Numerical Simulation and Test Of A Model Thermo-Adaptive Mirror
Authors: Reznichenko Vladimir V. , Kotov Victor V. , Leonov Yury V. , Smirnov Vladislav N. , Zvezdina Marina E.
Published: February 2023

The majority of wavefront disturbances of space reflector and space telescopes are due to external thermal fields variations and the optical surface deformations.
Optics Design of Compact Deformable Mirror Experiment
Authors: Dayton David , Laughlin Darren , Gonglewski John
Published: February 2023

Optical Design of a compact adaptive optics systems, to be mounted on the side of a large telescope presents special problems. In particular the limited space requires fast optics. Signal to noise requirements for the wave-front sensor also require that the optics work over a wide optical band. In this paper we describe the design and layout of such an adaptive optics experiment performed on the SOR 3.5 meter telescope.
CRICS - Confusion Rejection Image Compensation System
Authors: Wirth Allan , Jankevics Andrew
Published: February 2023

A novel concept for the compensation of aberrated images has been developed. It is based on the idea of introducing a pupil mask that blocks the most highly tilted portions of the incoming wavefront. Such a mask might consist of a spatial light modulator. The SLM would be driven by a binary Hartmann sensor. Subapertures with low tilt would turn on their corresponding SLM pixels allowing the nearly flat portions of the wavefront to propagate. Subapertures with larger tilts would act to turn off their SLM pixels, eliminating those portions of the pupil that don not contribute to the core of the image.
Liquid Crystals for Adaptive Optics
Authors: Restaino Sergio R. , Carreras Richard A. , Love Gordon D.
Published: February 2023

Adaptive optics components have been used for almost twenty years without major modifications of the basic hardware. Problems connected with cost, power consumption and reliability have pushed several groups to start, investigating the possibility of using different technologies. Of the many technologies under investigation two, in our opinion, demonstrate a high possibility of being an alternative to conventional adaptive mirrors. They are liquid crystal spatial light modulators and and micro-machined mirrors. The USAF Phillips Laboratory, is investigating both these technologies, however here we report, on the results of the liquid crystal work, which has a slightly longer history and more maturity.