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An efficient protocol for the asymmetric synthesis of unnatural amino acids is realized through photoredox-mediated C–O bond activation of oxalate esters derived from aliphatic alcohols as the radical precursors. The developed system uses chiral glyoxylate-derived N-sulfinyl imine as the radical acceptor and allows quick access to a range of functionalized unnatural amino acids through an atom-economical redox-neutral process with CO2 as the only stoichiometric by-product.

The article presents the results of research on the bioecological assessment of the effectiveness of the fertilizing properties of metallurgical waste in nutrient soils. As a result of studies to assess the toxic effects of water extracts from nutrient soils on the vital activity of daphnia (Daphnia magna), changes in the reaction of this test object were established depending on the composition of the components in the nutrient substrate. The degree of influence of the fertilizing effect of various types of nutrient soils based on soil, slag and zeolite on the germination, growth and development of seedlings of small-seeded vegetable culture of lettuce has been determined. Seed germination, plant growth and development are influenced by the water-physical properties of soils and the amount of available macroand microelements. The effectiveness of the use of visual and computer assessment of the color gamut of lettuce leaves for assessing the level of soil contamination by the intensity of nutrient consumption by plants is shown.

This research focuses on the discriminatory experiences that young African American women in the American South report as a function of their actual and perceived skin tone. Participants (N = 76) were given the Pantone Skin Tone guide (Pantone, 2017) and asked to find the best color (varying on undertone and lightness) that matched closely to their skin tone. Following that, an experimenter identified participants’ skin tone and they completed several questionnaires assessing perceived racism, discrimination, and self-esteem. Participants reported discrimination and biases that they regularly experience based on their skin tone and race. While qualitative data suggests that colorism does exist, the quantitative data did not establish a link between lightness of one’s skin tone and levels of perceived discrimination. Individuals who reported a high frequency of experiencing racism in their lives also perceived their skin tone darker without the mirror than with it. This finding establishes a link between negative race-based experiences and one’s self-perception of skin tone. While self-esteem did not moderate or mediate the skin tone-discrimination relationship, it was strongly related to reports of racism and colorism.

The article deals with the question of cancer myth representation in the popular science medical discourse. This study is carried out according to the linguocultural approach to the study of the cancer myth, which is based on the reconsideration of linguocultural phenomena. Myths about diseases are of linguistic and cultural significance and they are passed down from generation to generation. Those of phenomena that are incomprehensible and frightening are considered to cause additional associations. Cancer diseases refer to such linguocultural phenomena. Myths about diseases reflect the results of this or that form of reconsideration or experience of some phenomena by a particular linguocultural society. The work provides the definitions of the notions myth and disease. The methodology of the study is based on the research by foreign and Russian scientists in the field of study of the notions of myth and disease as semiotic systems. The popular science medical survey The Emperor of All Maladies: A Biography of Cancer by Siddhartha Mukherjee served as a research background. It analyses the way the disease myth actualizes in the popular science medical discourse. It shows a mythological plot (or mythological information) to get actualized in a particular situation by means of reference, and the way it contributes to the explication of a particular disease myth. Neither the subject of the message nor the plot of the myth is of importance for the reader, only the influence of the myth on the patients representations of disorder and his emotional state and on the society as a whole makes sense. The study helps conclude that mythological information representing the disease myth is nationally and socially marked, and is characterized by a particular conceptual presentation and is expressed by different linguistic means.

This work examines whether racial attitudes—when measured by both explicit and implicit measures— are driven primarily by skin tone, facial physiognomy, or both in 5 to 12-year-old children. Participants evaluated faces varying in skin tone (from dark to light) and facial physiognomy (from Afrocentric to Eurocentric). In an explicit task, children rated how much they liked each face. In an implicit task, participants completed a child-friendly version of the Affect Misattribution Procedure, where they rated a Chinese character as “good” or “bad” following a racial prime. Results suggest that pro-White attitudes (especially those measured by the explicit task) are driven by both factors, vary by perceivers’ race, and are present in both White and non-White children, though skin tone exerts a larger influence than other features, at least in explicit evaluations. Our results also raise the possibility that pro-White biases might be more internalized by non-White children in the American South.

A protocol for stereoselective C-radical addition to a chiral glyoxylate-derived N-sulfinyl imine was developed through visible light-promoted photoredox catalysis, providing a convenient method for the synthesis of unnatural α-amino acids. The developed protocol allows the use of ubiquitous carboxylic acids as radical precursors without prior derivatization. The protocol utilizes near-stoichiometric amounts of the imine and the acid radical precursor in combination with a catalytic amount of an organic acridinium-based photocatalyst. Alternative mechanisms for the developed transformation are discussed and corroborated by experimental and computational studies., A protocol for stereoselective C-radical addition to a chiral glyoxylate-derived N-sulfinyl imine was developed through visible light-promoted photoredox catalysis, providing a convenient method for the synthesis of unnatural α-amino acids.

In the tenth-century Byzantine sigillography, along with the classical iconographic repertoire (images of the Mother of God, saints, and cross potent), there appeared images of birds, real animals and monsters, and even portraits of the owners of seals. An important place among them belongs to the seals showing griffin, an imaginary monster combining the features of an eagle and a lion. Its images on seals comprise three variants: 1) single image of a griffin, 2) griffin trampling an animal, 3) paired griffins in the flight scene of Alexander the Great. Among the lead seals in the State Hermitage Museum collection, the first variant is represented by the seals of Theophylaktos Argyros, anthypatos patrikios; Stephen, protospatharios, episkeptites and the anagrapheus of the imperial domains protected by God; Constantine, imperial spatharokandidatos and kommerkiarios of Thessalonike; Theophylaktos, patrikios, imperial protospatharios, ἐπὶ τοῦ Χρυσοτρικλίνου and chartoularios of the dromos; Demetrios, imperial spatharokandidatos and ἐπὶ τῆς μεγάλης ἑταιρείας; George; and Theophilus (?). The second variant occurs on the seals of Leo, imperial protospatharios, ἐπὶ τῆς μεγάλης ἑταιρείας, and Staurakios, imperial protospatharios, ἐπὶ τῶν οἰκειακῶν and ἐπὶ τῶν βαρβάρων. The third variant shows a unique seal from the State Hermitage Museum featuring an image of SS. Constantine and Helena on the obverse. Taking the seals from other collections along with the sigillographic monuments from the State Hermitage Museum into account, the author of this paper has run to the conclusion that the appearance of the image of a griffin in the tenth century coincided with the Macedonian Renaissance and was connected mainly with the revival of interest in the antique past. It was the time when this image retained only its apotropaic and decorative function. It was placed on the seals of secular officials, civilian and the military persons.

Herein is reported the first total synthesis of benzyl salicylate and benzyl gentisate glucosides present in various plant species, in particular the Salix genus, such as Populus balsamifera and P. trichocarpa. The method permits the synthesis of several natural phenolic acid derivatives and their glucosides starting from salicylic or gentisic acid. The divergent approach afforded access to three different acetylated glucosides from a common synthetic intermediate. The key step in the total synthesis of naturally occurring glycosides-the selective deacetylation of the sugar moiety-was achieved in the presence of a labile benzyl ester group by employing mild deacetylation conditions. The protocol permitted synthesis of trichocarpine (4 steps, 40% overall yield), isotrichocarpine (3 steps, 51% overall yield), trichoside (6 steps, 40% overall yield), and deoxytrichocarpine (3 steps, 42% overall yield) for the first time (>95% purity). Also, the optimized mild deacetylation conditions allowed synthesis of 2-O-acetylated derivatives of all four glycosides (5-17% overall yield, 90-95% purity), which are rare plant metabolites.

This article analyzes the frequency and features of cardiac amyloidosis in the elderly. The morphology and pathogenesis of amyloid cardiomyopathy are presented. The features of the clinical picture of the heart and aortic lesions in systemic and local variants of amyloidosis are analyzed. Polymorbidity in older people, which complicates the diagnosis of cardiac amyloidosis and leads to a delay in treatment, is reviewed. The diagnostic methods of various types of cardiac amyloidosis are evaluated. Modern trends in the treatment of amyloidosis are presented.

In the present work, the synthesis of acetylated salicins, which occur naturally in many Salicaceae species, is reported. The preparation of 2-O-acetylsalicin, 2-O-acetylchlorosalicin, and 2-O-acetylethylsalicin from peracetylated bromosalicin with selective acid-catalyzed deacetylation and one-pot nucleophilic substitution of bromine as the key steps is described. The base-catalyzed O-2 → O-6 acetyl migration afforded 6-O-acetylsalicin derivatives in good yields. Thus, the first synthesis of 6-O-acetylsalicin (fragilin) using acetyl group migration is reported as well as the synthesis of 6-O-acetylchlorosalicin and 6-O-acetylethylsalicin. The NaOMe-catalyzed deacetylation of acetylated glycosides gave salicin, chlorosalicin, and ethylsalicin recently reported from Alangium chinense.

Рынок сегодня – огромное количество предложений товаров услуг, значительная доля которых реализуется через интернет-площадки. Как России удержать отечественных покупателей и построить свою систему, не зависящую от других стран, рассмотрено в данной статье.

В статье рассматривается воспитательная работа как совместные действия учителя, родителей и обучающихся, а также готовность педагога наблюдать, анализировать и корректировать процесс воспитания и личностного развития на примере исследования уровня воспитанности обучающихся 4–8 классов средней общеобразовательной школы.

In two studies, participants completed an implicit attractiveness task with faces as primes varying on (a) facial features from Afrocentric to Eurocentric and (b) skin tone from dark to light, and target pictures of environmental scenes varying in attractiveness. On each trial, participants were briefly primed with a face. Next, they categorized a target picture as either attractive or unattractive as quickly as possible. In addition, in Study 2, participants rated the same faces on an attractiveness scale. While results of Study 1 showed that when faces were medium in skin tone, participants were more accurate when primed with a Eurocentric face responding to attractive targets, but also more accurate when primed with an Afrocentric face responding to unattractive targets, a more powerful Study 2 failed to replicate this effect. There was no relationship between participants' explicit ratings of attractiveness and accuracy rates in the implicit attractiveness task.