scholarly journals A review of motivations, methods, and achievements on microgravity combustion research

2021 ◽  
Vol 300 ◽  
pp. 01021
Author(s):  
Shihong Ye ◽  
Miaomiao Hao ◽  
Haoran Guo ◽  
Lin Lu ◽  
Huanhuan Xu ◽  
...  
Keyword(s):  
Fire Safety ◽  
Soot Formation ◽  
Microgravity Environment ◽  
Comprehensive Review ◽  
Microgravity Combustion ◽  
The Past ◽  
Research Fields ◽  
Development Direction ◽  
Safety Strategies ◽  
New Generation

Microgravity combustion has always been one of the key and frontier research fields in the international combustion community. Why has microgravity combustion attracted so much attention? First of all, fire safety and combustion reliability are imminent to spacecraft. Secondly, the convection effect is weakened in the microgravity environment, and the basic combustion phenomena are more prominent, which is greatly helpful to study the fundamental laws of combustion and develop reliable combustion models for fuels. This article systematically summarized and analyzed the research focuses, namely fire safety of spacecraft, droplet combustion, soot formation and flame structures, and current research status in the field of microgravity combustion during the past decades of years. In this paper, motivations, methods, and achievements of fire safety in spacecraft and fundamental combustion characteristics in microgravity were analyzed, which provide a comprehensive review for the microgravity combustion research. Suggestions for the development direction of microgravity combustion science were also made. Improving the application of efficient and clean combustion and optimizing fire safety strategies of new generation spacecraft materials should still be regarded as two critical targets in the future.

The Contribution of Intermediate-Voltage, High-Resolution Electron Microscopy In Materials Science: An Appraisal

1990 ◽  
Vol 48 (1) ◽  
pp. 478-479
Author(s):  
John L. Hutchison
Keyword(s):  
High Resolution ◽  
Materials Science ◽  
High Resolution Electron Microscopy ◽  
Optical Diffraction ◽  
The Past ◽  
Resolution Electron ◽  
Extreme Sensitivity ◽  
Electron Microscopes ◽  
New Generation ◽  
Small Metal Particles

Over the past five years or so the development of a new generation of high resolution electron microscopes operating routinely in the 300-400 kilovolt range has produced a dramatic increase in resolution, to around 1.6 Å for “structure resolution” and approaching 1.2 Å for information limits. With a large number of such instruments now in operation it is timely to assess their impact in the various areas of materials science where they are now being used. Are they falling short of the early expectations? Generally, the manufacturers’ claims regarding resolution are being met, but one unexpected factor which has emerged is the extreme sensitivity of these instruments to both floor-borne and acoustic vibrations. Successful measures to counteract these disturbances may require the use of special anti-vibration blocks, or even simple oil-filled dampers together with springs, with heavy curtaining around the microscope room to reduce noise levels. In assessing performance levels, optical diffraction analysis is becoming the accepted method, with rotational averaging useful for obtaining a good measure of information limits. It is worth noting here that microscope alignment becomes very critical for the highest resolution.In attempting an appraisal of the contributions of intermediate voltage HREMs to materials science we will outline a few of the areas where they are most widely used. These include semiconductors, oxides, and small metal particles, in addition to metals and minerals.

Molecular Epidemiology and Biomarkers in Etiologic Cancer Research: The New in Light of the Old

2020 ◽  
Author(s):  
Lungwani Muungo
Keyword(s):  
Gene Expression ◽  
Cancer Research ◽  
Molecular Epidemiology ◽  
Exposure Assessment ◽  
Large Scale ◽  
First Generation ◽  
Cancer Epidemiology ◽  
Policy Changes ◽  
The Past ◽  
New Generation

The purpose of this review is to evaluate progress inmolecular epidemiology over the past 24 years in canceretiology and prevention to draw lessons for futureresearch incorporating the new generation of biomarkers.Molecular epidemiology was introduced inthe study of cancer in the early 1980s, with theexpectation that it would help overcome some majorlimitations of epidemiology and facilitate cancerprevention. The expectation was that biomarkerswould improve exposure assessment, document earlychanges preceding disease, and identify subgroupsin the population with greater susceptibility to cancer,thereby increasing the ability of epidemiologic studiesto identify causes and elucidate mechanisms incarcinogenesis. The first generation of biomarkers hasindeed contributed to our understanding of riskandsusceptibility related largely to genotoxic carcinogens.Consequently, interventions and policy changes havebeen mounted to reduce riskfrom several importantenvironmental carcinogens. Several new and promisingbiomarkers are now becoming available for epidemiologicstudies, thanks to the development of highthroughputtechnologies and theoretical advances inbiology. These include toxicogenomics, alterations ingene methylation and gene expression, proteomics, andmetabonomics, which allow large-scale studies, includingdiscovery-oriented as well as hypothesis-testinginvestigations. However, most of these newer biomarkershave not been adequately validated, and theirrole in the causal paradigm is not clear. There is a needfor their systematic validation using principles andcriteria established over the past several decades inmolecular cancer epidemiology.

Vēsturiskā atmiņa Latvijas teātra jaunās paaudzes mākslinieku darbos: izrādes „Dvēseļu utenis” piemērs

2020 ◽  
pp. 269-275
Author(s):  
Ieva Rodiņa
Keyword(s):  
Historical Memory ◽  
Intergenerational Relationships ◽  
Phenomenological Approach ◽  
Political Theater ◽  
Hermeneutic Phenomenological ◽  
The Past ◽  
The Social ◽  
Humanistic Study ◽  
New Generation ◽  
Flea Market

The aim of the research “Historical Memory in the Works of the New Generation of Latvian Theater Artists: The Example of “The Flea Market of the Souls” is to focus on the current but at the same time little discussed topic in Latvian theater – the change of generations and the social processes connected to it, that are expressed on the level of world views, experiences, intergenerational relationships. Most directly, these changes are reflected in the phenomenon of historical memory. The concept of “postmemory” was defined by German professor Marianne Hirsch in 1992, suggesting that future generations are closely related to the personal and collective cultural traumas of previous generations, which are passing on the past experience through historical memory, thus affecting the present. Grotesque, self-irony, and focusing on socio-political, provocative questions and themes are the connecting point of the generation of young Latvian playwrights born in the late 1980s and early 1990s, including such personalities as Jānis Balodis, Rasa Bugavičute-Pēce, Matīss Gricmanis, Justīne Kļava, etc. However, unlike Matīss Gricmanis or Janis Balodis who represent the aesthetics of political theater, in Justīne Kļava’s works, sociopolitical processes become the background of a generally humanistic study of the relationships between generations. This theme is represented not only in “The Flea Market of the Souls”, but also in other plays, like “Jubilee ‘98” and “Club “Paradise””. The tendency to investigate the traces left by the Soviet heritage allows to define these works as autobiographical researches of the identity of the post-Soviet generation, analyzing life in today's Latvia in terms of historical memory. Using the semiotic, hermeneutic, phenomenological approach, the play “The Flea Market of the Souls” and its production in Dirty Deal Teatro (2017) are analyzed as one of the most vivid works reflecting the phenomenon of historical memory in recent Latvian original drama.

Synthesis of Drugs and Biorelevant N-heterocycles Employing Recent Advances in C-N Bond Formation

2020 ◽  
Vol 24 (20) ◽  
pp. 2293-2340
Author(s):  
Firdoos Ahmad Sofi ◽  
Prasad V. Bharatam
Keyword(s):  
Kinase Inhibitors ◽  
Bond Formation ◽  
Comprehensive Review ◽  
Biologically Relevant ◽  
Lead Compounds ◽  
Heterocyclic Molecules ◽  
The Past ◽  
Anti Cancer ◽  
Modern Methods ◽  
Bond Formation Reactions

C-N bond formation is a particularly important step in the generation of many biologically relevant heterocyclic molecules. Several methods have been reported for this purpose over the past few decades. Well-known named reactions like Ullmann-Goldberg coupling, Buchwald-Hartwig coupling and Chan-Lam coupling are associated with the C-N bond formation reactions. Several reviews covering this topic have already been published. However, no comprehensive review covering the synthesis of drugs/ lead compounds using the C-N bond formation reactions was reported. In this review, we cover many modern methods of the C-N bond formation reactions, with special emphasis on metal-free and green chemistry methods. We also report specific strategies adopted for the synthesis of drugs, which involve the C-N bond formation reactions. Examples include anti-cancer, antidepressant, anti-inflammatory, anti-atherosclerotic, anti-histaminic, antibiotics, antibacterial, anti-rheumatic, antiepileptic and anti-diabetic agents. Many recently developed lead compounds generated using the C-N bond formation reactions are also covered in this review. Examples include MAP kinase inhibitors, TRKs inhibitors, Polo-like Kinase inhibitors and MPS1 inhibitors.

Phytochemical and Pharmacological Review on Two Herbs of Baijiangcao: Patrinia scabiosaefolia Fisch. ex Trev. and Patrinia villosa (Thunb.) Juss

2020 ◽  
Vol 17 (5) ◽  
pp. 496-517
Author(s):  
Yangcheng Liu ◽  
Wei Liu ◽  
Jiaqi Wang ◽  
Yang Liu ◽  
Changlan Chen ◽  
...  
Keyword(s):  
Chemical Constituents ◽  
Volatile Components ◽  
Research Papers ◽  
Pharmacological Activities ◽  
Comprehensive Review ◽  
Scientific Databases ◽  
The Past ◽  
Current State ◽  
Patrinia Scabiosaefolia ◽  
Antiviral Activities

Patrinia scabiosaefolia Fisch. Trev. and Patrinia villosa (Thunb.) Juss, are two species of Patrinia recorded in the Chinese Pharmacopoeia with the same Chinese name “Baijiangcao” and similar therapeutic effect in traditional Chinese medicine. The present article is the first comprehensive review on the chemical composition and pharmacological activities of these herbs. In this review, data on chemical constituents and pharmacological profile of the two herbs are provided. This review discusses all the classes of the 223 compounds (phenylpropanoids, flavonoids, terpenes, saponins and volatile components, etc.) detected in the two herbs providing information on the current state of knowledge of the phytochemicals present in them. In the past three years, our research group has isolated and identified about more than 100 ingredients from the two herbs. Therefore, we published a systematic review of our research papers and studies on the two herbs were carried out using resources such as classic books about Chinese herbal medicine and scientific databases including Pubmed, Web of Science, SciFinder, CNKI. etc. The present review discusses the most thoroughly studied pharmacological activities (antioxidant, anti-inflammatory, immunomodulatory, antimicrobial, antitumor and antiviral activities) of the two herbs. This comprehensive review will be informative for scientists searching for new properties of these herbs and will be important and significant for the discovery of bioactive compounds from the two herbs and in complete utilization of Patrinia scabiosaefolia Fisch. ex Trev. and Patrinia villosa (Thunb.) Juss.

The Twenty-first Century

2018 ◽  
Author(s):  
Alexander Gillespie
Keyword(s):  
Environmental Sustainability ◽  
First Century ◽  
Bad News ◽  
Good News ◽  
Species Loss ◽  
The Past ◽  
Scientific Terms ◽  
Twenty First Century ◽  
Open Question ◽  
New Generation

The cumulative environmental challenge of sustainable development in the twenty-first century is larger than anything humanity has ever had to deal with in the past. The good news is that solid progress is being reached in the understanding of issues in scientific terms and understanding what needs to be done. The bad news is twofold. First, although many of the environmental problems of earlier centuries are now being confronted, a new generation of difficulties is eclipsing what were the older difficulties. Secondly, much of the progress is being achieved by the wealthier parts of the planet, rather than the developing world. From population growth to climate change to unprecedented habitat and species loss, whether environmental sustainability can be achieved in the twenty-first century is an open question.

scholarly journals The evolution of Darwinian sexualities

BJHS Themes ◽  
2021 ◽  
pp. 1-23
Author(s):  
Erika Lorraine Milam
Keyword(s):  
Gay Rights ◽  
First Century ◽  
Sexual Practices ◽  
Past Century ◽  
Sexual Preferences ◽  
The Past ◽  
Sexual Behaviours ◽  
Late Twentieth ◽  
New Generation ◽  
Descent Of Man

Abstract Charles Darwin's Descent of Man was suffused with questions of courtship, mating and sex. Following in his footsteps, biologists throughout the twentieth century interrogated the sexual behaviour of humans and animals. This paper charts the fate of evolutionary theories of sexuality to argue that – despite legal and social gains of the past century – when biologists used sexual selection as a tool for theorizing the evolution of homosexual behaviour (which happened only rarely), the effect of their theories was to continuously reinscribe normative heterosexuality. If, at the end of the nineteenth century, certain sex theorists viewed homosexuality as a marker of intermediate sex, by the late twentieth a new generation of evolutionary theorists idealized gay men as hyper-masculine biological males whose sexual behaviours were uncompromised by the necessity of accommodating women's sexual preferences. In both cases, normative assumptions about gender were interwoven with those about sexuality. By the twenty-first century, animal exemplars were again mobilized alongside data gathered about human sexual practices in defence of gay rights, but this time by creating the opportunity for naturalization without recourse to biological determinism.

Corrigendum to: Lamprothamnium in Australia (Characeae, Charophyceae)

2013 ◽  
Vol 26 (6) ◽  
pp. 475
Author(s):  
Michelle T. Casanova
Keyword(s):  
New Species ◽  
Species Level ◽  
Type Material ◽  
Review Of The Literature ◽  
Comprehensive Review ◽  
The Past

Charophytes in the genus Lamprothamnium exhibit a large amount of diversity, particularly in the examples from Australia, although little of that variation has been recognised at species level in the past. The Australian members of the genus are revised here on the basis of extensive new collections, examination of specimens in herbaria and comprehensive review of the literature and available type material. The existing species Lamprothamnium macropogon (A.Braun) Ophel, L. inflatum (Fil. & G.O.Allen ex Fil.) A.García & Karol and L. heraldii A.García & Casanova are retained, eight new species are described (L. australicum Casanova, L. beilbyae Casanova, L. capitatum Casanova, L. compactum Casanova, L. coorongense Casanova, L. diminutum Casanova, L. macroanthum Casanova and L. stipitatum Casanova) and two taxa variously treated at infraspecific rank in Lychnothamnus are transferred to Lamprothamnium at species rank (L. cockajemmyense Casanova, L. tasmanicum (A.Braun) Casanova). Neither L. papulosum (Wallr.) J.Groves nor L. succinctum (A.Braun) R.D.Wood are confirmed for Australia after examination of the type material of these species. Species are distinguished by the arrangement of the gametangia, morphology of the fertile whorls and characteristics of the oospores. Four of these species are dioecious and nine are monoecious, which supports published conjectures concerning the biogeography of charophyte species (Proctor (1980): J. Phycol. 16, 218–233, doi:10.1111/j.1529-8817.1980.tb03023.x).

Corruption and anti-corruption local discourses and international practices in post-socialist Romania

Human Affairs ◽  
2013 ◽  
Vol 23 (2) ◽  
Author(s):  
Filippo Zerilli
Keyword(s):  
Cultural History ◽  
Research Literature ◽  
The European Union ◽  
The Past ◽  
Research Fields ◽  
Nation States ◽  
National Heritage ◽  
New Research ◽  
Local Discourses ◽  
The Cold War

AbstractIn the past two decades academic and research literature on “corruption” has flourished. During the same period organizations and initiatives fighting against corruption have also significantly expanded, turning “anti-corruption” into a new research subject. However, despite a few exceptions there is a division of labor between scholars who study corruption itself and those who study the global anti-corruption industry. Juxtaposing corruption’s local discourses and anti-corruption international practices, this article is an attempt to bring together these two intertwined research dimensions and explore how an ethnographic approach might contribute to framing them together. Firstly, it describes how corruption in Romania is often conceptualized and explained in terms of national heritage, something related to old and recent cultural history, including traditional folklore. Secondly, it explores how anti-corruption works in practice, focusing on international legal cooperation projects monitoring the progress and shortcomings both prior to and post Romania’s accession to the European Union. Finally, revealing the articulations of these two apparently unrelated research fields, the article argues that corruption’s local explanations and the circular logic of auditing observed within the anti-corruption industry share a common developmental ideology mirroring the crypto-colonialist structure of power relations and dependency among European nation-states emerging out of the Cold War.

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