Analytical investigation of hybrid composite precast beams with modified strain compatibility for entire history of nominal flexural capacity

2015 ◽  
Vol 24 (13) ◽  
pp. 835-852 ◽  
Author(s):  
Won-Kee Hong ◽  
Yongjei Lee ◽  
Sunkuk Kim ◽  
Seung-il Kim ◽  
Yeo-jin Yun
Author(s):  
Petr Ilyin

Especially dangerous infections (EDIs) belong to the conditionally labelled group of infectious diseases that pose an exceptional epidemic threat. They are highly contagious, rapidly spreading and capable of affecting wide sections of the population in the shortest possible time, they are characterized by the severity of clinical symptoms and high mortality rates. At the present stage, the term "especially dangerous infections" is used only in the territory of the countries of the former USSR, all over the world this concept is defined as "infectious diseases that pose an extreme threat to public health on an international scale." Over the entire history of human development, more people have died as a result of epidemics and pandemics than in all wars combined. The list of especially dangerous infections and measures to prevent their spread were fixed in the International Health Regulations (IHR), adopted at the 22nd session of the WHO's World Health Assembly on July 26, 1969. In 1970, at the 23rd session of the WHO's Assembly, typhus and relapsing fever were excluded from the list of quarantine infections. As amended in 1981, the list included only three diseases represented by plague, cholera and anthrax. However, now annual additions of new infections endemic to different parts of the earth to this list take place. To date, the World Health Organization (WHO) has already included more than 100 diseases in the list of especially dangerous infections.


Author(s):  
Roy Livermore

Tuzo Wilson introduces the concept of transform faults, which has the effect of transforming Earth Science forever. Resistance to the new ideas is finally overcome in the late 1960s, as the theory of moving plates is established. Two scientists play a major role in quantifying the embryonic theory that is eventually dubbed ‘plate tectonics’. Dan McKenzie applies Euler’s theorem, used previously by Teddy Bullard to reconstruct the continents around the Atlantic, to the problem of plate rotations on a sphere and uses it to unravel the entire history of the Indian Ocean. Jason Morgan also wraps plate tectonics around a sphere. Tuzo Wilson introduces the idea of a fixed hotspot beneath Hawaii, an idea taken up by Jason Morgan to create an absolute reference frame for plate motions.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Chin Jian Yang ◽  
Joanne Russell ◽  
Luke Ramsay ◽  
William Thomas ◽  
Wayne Powell ◽  
...  

AbstractDistinctness, Uniformity and Stability (DUS) is an intellectual property system introduced in 1961 by the International Union for the Protection of New Varieties of Plants (UPOV) for safeguarding the investment and rewarding innovation in developing new plant varieties. Despite the rapid advancement in our understanding of crop biology over the past 60 years, the DUS system has changed little and is still largely dependent upon a set of morphological traits for testing candidate varieties. As the demand for more plant varieties increases, the barriers to registration of new varieties become more acute and thus require urgent review to the system. To highlight the challenges and remedies in the current system, we evaluated a comprehensive panel of 805 UK barley varieties that span the entire history of DUS testing. Our findings reveal the system deficiencies such as inconsistencies in DUS traits across environments, limitations in DUS trait combinatorial space, and inadequacies in currently available DUS markers. We advocate the concept of genomic DUS and provide evidence for a shift towards a robust genomics-enabled registration system for new crop varieties.


2020 ◽  
Vol 2020 (12) ◽  
Author(s):  
Hsu-Wen Chiang ◽  
Yu-Hsien Kung ◽  
Pisin Chen

Abstract One interesting proposal to solve the black hole information loss paradox without modifying either general relativity or quantum field theory, is the soft hair, a diffeomorphism charge that records the anisotropic radiation in the asymptotic region. This proposal, however, has been challenged, given that away from the source the soft hair behaves as a coordinate transformation that forms an Abelian group, thus unable to store any information. To maintain the spirit of the soft hair but circumvent these obstacles, we consider Hawking radiation as a probe sensitive to the entire history of the black hole evaporation, where the soft hairs on the horizon are induced by the absorption of a null anisotropic flow, generalizing the shock wave considered in [1, 2]. To do so we introduce two different time-dependent extensions of the diffeomorphism associated with the soft hair, where one is the backreaction of the anisotropic null flow, and the other is a coordinate transformation that produces the Unruh effect and a Doppler shift to the Hawking spectrum. Together, they form an exact BMS charge generator on the entire manifold that allows the nonperturbative analysis of the black hole horizon, whose surface gravity, i.e. the Hawking temperature, is found to be modified. The modification depends on an exponential average of the anisotropy of the null flow with a decay rate of 4M, suggesting the emergence of a new 2-D degree of freedom on the horizon, which could be a way out of the information loss paradox.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Weizhao Yang ◽  
Nathalie Feiner ◽  
Catarina Pinho ◽  
Geoffrey M. While ◽  
Antigoni Kaliontzopoulou ◽  
...  

AbstractThe Mediterranean basin is a hotspot of biodiversity, fuelled by climatic oscillation and geological change over the past 20 million years. Wall lizards of the genus Podarcis are among the most abundant, diverse, and conspicuous Mediterranean fauna. Here, we unravel the remarkably entangled evolutionary history of wall lizards by sequencing genomes of 34 major lineages covering 26 species. We demonstrate an early (>11 MYA) separation into two clades centred on the Iberian and Balkan Peninsulas, and two clades of Mediterranean island endemics. Diversification within these clades was pronounced between 6.5–4.0 MYA, a period spanning the Messinian Salinity Crisis, during which the Mediterranean Sea nearly dried up before rapidly refilling. However, genetic exchange between lineages has been a pervasive feature throughout the entire history of wall lizards. This has resulted in a highly reticulated pattern of evolution across the group, characterised by mosaic genomes with major contributions from two or more parental taxa. These hybrid lineages gave rise to several of the extant species that are endemic to Mediterranean islands. The mosaic genomes of island endemics may have promoted their extraordinary adaptability and striking diversity in body size, shape and colouration, which have puzzled biologists for centuries.


Diagnosis ◽  
2015 ◽  
Vol 2 (2) ◽  
pp. 137-140 ◽  
Author(s):  
Wycliffe Mbagaya ◽  
Joanne Foo ◽  
Ahai Luvai ◽  
Claire King ◽  
Sarah Mapplebeck ◽  
...  

AbstractMacrocomplexes between immunoglobins and aspartate aminotransferase (macro-AST) may result in persistently increased AST concentration. The presence of macro-AST in patients has been implicated in unnecessary investigations of abnormal liver function tests. We report the case of a 44-year-old female who presented to the rheumatology clinic with a 12-months’ history of constant widespread pain affecting her limbs and was found to have an elevated AST concentration. Further information from her GP revealed a 14-years’ history of elevated AST with otherwise normal liver function. Previous abdominal ultrasound and two liver biopsies carried out 2 years apart were normal. This prompted further analytical investigation by the biochemistry department which identified macro-AST as the cause. This case illustrates that persistently raised isolated AST concentration with no other abnormal indices may warrant macroenzyme analysis potentially avoiding unnecessary invasive investigations.


2021 ◽  
Vol 49 (3) ◽  
pp. 12-32

A brief overview of the main historical events that accompanied the formation and establishment of the Laboratory of Oceanology in the Academy of Sciences in 1941 is given. Then, a few years later, the Laboratory was transformed into the Institute of Oceanology, the director of which was appointed the Minister of the Merchant Fleet of the USSR, Academician P. P. Shirshov. By his initiative in 1949, the Institute became the owner of its first large research vessel "Vityaz". It is shown that the entire history of the institute and its research team was primarily based on the development and generalization of the results of regular sea and ocean expeditions. The article provides general information about the results obtained in the recent past, and their development and deepening in the works of the institute at present.


2008 ◽  
Vol 2 (2) ◽  
Author(s):  
Alan Sondheim

The Internet Text is an extended analysis of the environment of Internet communication, an extended meditation on the psychology and philosophy of Net exchange. As such, it is concerned primarily with virtual or electronic subjectivity – the simultaneous presence and absence of the user, the sorts of libidinal projections that result, the nature of flamewars, and the ontological or epistemological issues that underlie these processes. Internet Text begins with a brief, almost corrosive, account of the subject – an account based on the concepts of Address, Protocol, and Recognition. This section “reduces” virtual subjectivity to packets of information, Internet sputterings, and an ontology of the self based on Otherness – your recognition of me is responsible for my Net-presence. The reduction then begins to break down through a series of further texts detailing the nature of this presence; a nature which is both sexualized/gendered, and absenting, the result of an imaginary site. Eventually, it has become clear that everything revolves around issues of the virtual subject, who is only virtual on the Net, but who has a very real body elsewhere. So Internet Text has evolved more and more in a meditation on this subject – a subject which will perhaps be one of the dominant modes of being within the next millennium. Finally, it should be noted that there are no conclusions to be drawn in Internet Text, no series of protocol statements or declarations creating any sort of ultimate defining or explanatory position. The entire history of philosophy mitigates against this; instead, I side with the Schlegels, with Nietzsche, Bataille, Jabes, and others, for whom the fragment is crucial to an understanding of contemporary life... It is dedicated to Michael Current and Clara Hielo.


Author(s):  
James W. Giancaspro ◽  
Christos G. Papakonstantinou ◽  
P. N. Balaguru

By far, carbon and glass fibers are the most popular fiber reinforcements for composites. Traditional carbon composites are relatively expensive since the manufacturing process requires significant heat and pressure, while the carbon fibers themselves are inherently expensive to produce. In addition, they are often flammable and their use is restricted when fire is a critical design parameter. Glass fabrics are approximately one order of magnitude less expensive than similar carbon fabrics. However, they lack the stiffness and the durability needed for many high performance applications. By combining these two types of fibers, hybrid composites can be fabricated that are strong, yet relatively inexpensive to produce. The primary objective of this study was to experimentally investigate the effects of bonding high strength carbon fibers to E-glass composite cores using a high temperature, inorganic matrix known as geopolymer. Carbon fibers were bonded to E-glass cores (i) on only the tension face, (ii) on both the tension and compression faces, or (iii) dispersed throughout the core in alternating layers to obtain a strong, yet economical, hybrid composite laminate. For each response measured (flexural capacity, stiffness, and ductility), at least one hybrid configuration displayed mechanical properties comparable to all carbon composite laminates. The results indicate that hybrid composite plates manufactured using 3k unidirectional carbon tape exhibit increases in flexural capacity of approximately 700% over those manufactured using E-glass fibers alone. In general, as the relative amount of carbon fibers increased, the likelihood of precipitating a compression failure also increased. For 92% of the specimens tested, the threshold for obtaining a compression failure was utilizing 30% carbon fibers. The results presented herein can dictate future studies to optimize hybrid performance and to achieve economical configurations for a given set of design requirements.


Author(s):  
Mihai Răzvan Niță ◽  
Miruna Arsene ◽  
Giorgiana Barbu ◽  
Alina Gabriela Cus ◽  
Mihail Ene ◽  
...  

In the context of increasing urbanization and associated economic, social and environmental challenges, cities have increasingly acknowledged the importance of urban parks in delivering social, economic and environmental benefits to the population. The importance has been demonstrated also during the COVID-19 pandemic that generated lockdowns and reduced the capacity of urban inhabitants in accessing such benefits. The present study aims to determine how the presence in urban parks was reflected on social media during the pandemic period of 2020. We examined Instagram posts associated with a sample of eight urban parks in Bucharest, Romania and also the entire history of Google reviews between January and August 2020. The selection of parks was made according to their size, location in Bucharest, previous reported number of visitors and profile of attractiveness. Results revealed that the peak period of the COVID-19 pandemic and the first initiation of the lockdowns strongly affected the recreation and leisure activities that people performed almost daily in the parks of Bucharest. Reviews and comments of the population were not that focused on the pandemic even after the restrictions were lifted, but they evidenced the positive and negative aspects of each park. Our results can represent a useful instrument for local administrations in determining both the flow of visitors but also their perceptions towards the endowments, landscape and most important management of urban parks.


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