Parent crater for Australasian tektites beneath the sands of the Alashan Desert, Northwest China: Best candidate ever?

ABSTRACT Australasian tektites represent the largest group of tektites on Earth, and their strewn field covers up to one sixth of Earth’s surface. After several decades of fruitless quest for a parent crater for Australasian tektites, mostly in the main part of the strewn field in Indochina, the crater remains undiscovered. We elaborate upon a recently suggested original hypothesis for the impact in the Alashan Desert in Northwest China. Evidence from geochemical and isotopic compositions of potential source materials, gravity data, and geographic, paleoenvironmental, and ballistic considerations support a possible impact site in the Badain Jaran part of the Alashan Desert. In further support of an impact location in China, glassy microspherules recovered from Chinese loess may be the right age to relate to the Australasian tektite event, perhaps as part of the impacting body. The most serious shortcomings of the commonly accepted Indochina impact location include signs of little chemical weathering of source materials of Australasian tektites, unlike highly weathered sedimentary targets in Indochina, and questionable assumptions about transport of distal ejecta.

THE OLDEST ROCK ART SITES OF THE KARATAU RANGE: PETROGLYPHS OF KARASUYIR

Статья посвящена новому памятнику наскального искусства хребта Каратау, открытому в урочище Карасуйир. Приводится краткое описание памятника, публикуются наиболее важные изображения. Сюжеты и стилистические особенности основной чaсти петроглифов памятника Карасуйир связаны с эпохой бронзы, остaльные рисунки отнесены к эпохе рaннего железа и, возможно, к эпохе камня. Для некоторых из них предложена предварительная интерпретация. The article is devoted to a new rock art site of the Karatau Range, discovered in the Karasuyir Area. A brief description of the site is provided, and the most important images are published. Subjects and stylistic features of the main part of Karasuyir petroglyphs are associated with the Bronze Age, and other engravings are related to the early Iron Age and, perhaps, to the Stone Age. A preliminary interpretation is proposed for some of them.

Supercritical CO2 Extraction of Narcissus poeticus L. Flowers for the Isolation of Volatile Fragrance Compounds

The flowers of Narcissus poeticus are used for the isolation of valuable fragrance substances. So far, as the majority of these substances consist of volatile and sensitive to heat compounds, there is a need of developing effective methods for their recovery. In this study, freeze-dried N. poeticus inflorescences were extracted with pure supercritical CO2 (SFE-CO2) and its mixture with 5% co-solvent ethanol (EtOH) at 40 °C. Extract yields varied from 1.63% (12 MPa) to 3.12% (48 MPa, 5% EtOH). In total, 116 volatile compounds were identified by GC-TOF/MS in the extracts, which were divided into 20 different groups. Benzyl benzoate (9.44–10.22%), benzyl linoleate (1.72–2.17%) and benzyl alcohol (0.18–1.00%) were the major volatiles among aromatic compounds. The amount of the recovered benzyl benzoate in N. poeticus SFE-CO2 extracts varied from 58.98 ± 2.61 (24 MPa) to 91.52 ± 1.36 (48 MPa) mg/kg plant dry weight (pdw). α-Terpineol dominated among oxygenated monoterpenes (1.08–3.42%); its yield was from 9.25 ± 0.63 (12 MPa) to 29.88 ± 1.25 (48 MPa/EtOH) mg/kg pdw. Limonene was the major monoterpene hydrocarbon; (3E)-hexenol and heneicosanol dominated among alcohols and phenols; dihydroactinidiolide and 4,8,12,16-tetramethyl heptadecan-4-olide were the most abundant lactones; heptanal, nonanal, (2E,4E)-decadienal and octadecanal were the most abundant aldehydes. The most important prenol lipids were triterpenoid squalene, from 0.86 ± 0.10 (24 MPa) to 7.73 ± 0.18 (48 MPa/EtOH) mg/kg pdw and D-α-tocopherol, from 1.20 ± 0.04 (12 MPa) to 15.39 ± 0.31 (48 MPa/EtOH) mg/kg pdw. Aliphatic hydrocarbons (waxes) constituted the main part (41.47 to 54.93%) in the extracts; while in case of a 5% EtOH the percentage of alkanes was the lowest. The fraction of waxes may be removed for the separation of higher value fragrance materials. In general, the results obtained are promising for a wider application of SFE-CO2 for the recovery of fragrance substances from N. poeticus flowers.

Dynamics of Open Quantum Systems I, Oscillation and Decay

We develop a framework to analyze the dynamics of a finite-dimensional quantum system S in contact with a reservoir R. The full, interacting SR dynamics is unitary. The reservoir has a stationary state but otherwise dissipative dynamics. We identify a main part of the full dynamics, which approximates it for small values of the SR coupling constant, uniformly for all times t≥0. The main part consists of explicit oscillating and decaying parts. We show that the reduced system evolution is Markovian for all times. The technical novelty is a detailed analysis of the link between the dynamics and the spectral properties of the generator of the SR dynamics, based on Mourre theory. We allow for SR interactions with little regularity, meaning that the decay of the reservoir correlation function only needs to be polynomial in time, improving on the previously required exponential decay.In this work we distill the structural and technical ingredients causing the characteristic features of oscillation and decay of the SR dynamics. In the companion paper [27] we apply the formalism to the concrete case of an N-level system linearly coupled to a spatially infinitely extended thermal bath of non-interacting Bosons.

Creating Educational Robots

After more than 30 years of development, the designing, constructing, and programming of educational robots is still enjoying increasing popularity in formal, non-formal, and informal educational settings. Although building instructions and required technical components are easily available and accessible, the realization of own teaching projects is a special challenge and is subject to decisive influences. This includes the content-related training of teachers as well as their attitudes and ways of thinking and acting. Therefore, the first section of this chapter spans an arc from the didactic concept of the extracurricular project technikcamps related to robotics. The experiences gained from it and the consequences for teacher training to the philosophical roots of technical education follows. In connection with this, the main part deals with the technological basics of creating educational robots in general. It leads from manufacturing single parts through the creation of a support structure and automation to the application of the engineering design process.

Особенности применения теоремы вириала для магнитных систем с квазибессиловыми обмотками

The article shows that in a magnetic system with a thin-walled balanced winding close to a force-free one, a significant increase in the parameter θ=WM γ/M σМ , is possible, which, according to the virial theorem, characterizes the ratio of the energy of the magnetic system WM to the weight of equipment with a material density γ, where under the action of electromagnetic forces there appears a mechanical stress σМ. In a quasi-force-free magnetic system, the main part of the winding is in a state of local equilibrium, and only a relatively small part of the equipment is subject to stress. This part determines the weight of the entire system, and this weight can be minimized. The configurations of balanced thin-walled windings are developed, at the boundaries two boundary conditions are fulfilled simultaneously - the absence of the induction component normal to the boundary and the constancy of the product of induction and radius. The authors consider an example of a system consisting of a main part - a sequence of balanced "transverse" modules in the form of flat discs and end parts, consisting of a combination of "transverse" modules and "longitudinal" ones, having the form of rings elongated along the axis with balanced end parts. It is shown that in the system under consideration, the characteristic dimensionless parameter θ with an unlimited increase in the number of elements of the main part can reach a value of about 24, and when the number of these elements changes within 20 - 40, it changes from 6 to 9.

A Cybersecurity Skills Framework

This chapter traces the evolution of cybersecurity skills requirements and development over the past 40 years, from the early days of computer security (Compusec) to the present day. The development of cybersecurity skills is traced from an initial focus upon national security and confidentiality through to the current recognition as business driver. The main part of the chapter concentrates on the development of a specific skills framework from the Institute of Information Security Professionals. Originally conceived in 2006 and initially used for purposes of membership accreditation, the IISP Skills Framework has since been used extensively by commerce, industry, government and academia in the UK and more widely. Version 2 of the framework was published in 2016, and the chapter discussion outlines both the original structure and the notable changes in the later release. These developments collectively illustrate the ongoing recognition of cybersecurity skills, as well as the evolution of the skills themselves.

Mellin–Barnes integrals and the method of brackets

The method of brackets is a method for the evaluation of definite integrals based on a small number of rules. This is employed here for the evaluation of Mellin–Barnes integral. The fundamental idea is to transform these integral representations into a bracket series to obtain their values. The expansion of the gamma function in such a series constitute the main part of this new application. The power and flexibility of this procedure is illustrated with a variety of examples.

Piśmiennictwo religijne polskich Tatarów w okresie powojennym (1945–1989)

Religious Literature of Polish Tatars in the Post-War Period (1945–1989)The article opens with a general overview of the socio-political situation of the Tatars and the specificity of their religiosity in the People’s Republic of Poland (1945–1989), leading to the main part: an analysis of ephemeral religious prints created and distributed by Polish Tatars. The description of the sources is introduced with a presentation of the broad socio-political context which determined the functioning of this minority after World War II. The study characterises the basic types of religious literature of the Tatars: (a) traditional manuscripts, (b) periodicals and publishing activities, (c) ephemeral prints. It also considers the significance of these types of literature in the period between 1945 and 1989. The analysis of seven prayer books and three teaching materials provides the basis of general observations concerning ephemeral religious prints created by Polish Tatars after World War II. The analysed sources have not as yet been studied by researchers. Piśmiennictwo religijne polskich Tatarów w okresie powojennym (1945–1989)Artykuł rozpoczyna się od przybliżenia położenia społeczno-politycznego Tatarów w PRL-u oraz specyfiki ich religijności, by dojść do szczegółowych kwestii, związanych z analizą religijnych druków ulotnych opracowanych przez polskich Tatarów. Charakterystykę opartą na źródłach poprzedziło zatem przedstawienie szerokiego kontekstu społeczno-politycznego, który determinował sposób funkcjonowania tej mniejszości w Polsce po II wojnie światowej. Autorzy scharakteryzowali podstawowe typy piśmiennictwa religijnego Tatarów: a) tradycyjne rękopiśmiennictwo, b) czasopiśmiennictwo i działalność wydawniczą, c) druki ulotne. Zwrócono przy tym uwagę na znaczenie poszczególnych rodzajów piśmiennictwa w okresie 1945–1989. Charakterystyki religijnych druków ulotnych, opracowanych przez polskich Tatarów po II wojnie światowej, dokonano na przykładzie 7 modlitewników oraz 3 materiałów dydaktycznych. Dokumenty te dotąd nie były przedmiotem badań naukowych.

Beer in Antiquity, Antiquity in Beer?

Modern breweries taking inspiration from ancient cultures appear as a quite interesting phenomenon, because beer is absent from the current imaginarium about the ancient Greeks and Romans. Yet it was not unknown to them, as demonstrated by the survey of sources in the first part of the text. Actually, some brewers today are aware of the beverage’s presence in ancient literature and use this knowledge in the naming of their products. Others decide on less direct references, to some historical or mythical characters. Some producers do not limit themselves to names of their brews, but also attempt to reconstruct the ancient drinks. In the second (main) part of the article several cases of each type are presented, together with an analysis of methods of the references’ presentation and explanation to the consumer. Also, some observations are made about the reasons why breweries decide to use ancient themes at all.