Chalk fractures geometry: a comprehensive description of fracture surfaces

2018 ◽  
Author(s):  
M-L. Wattier ◽  
F. Descamps ◽  
S. Vandycke ◽  
J-P. Tshibangu
Author(s):  
Russell L. Steere ◽  
Michael Moseley

A redesigned specimen holder and cap have made possible the freeze-etching of both fracture surfaces of a frozen fractured specimen. In principal, the procedure involves freezing a specimen between two specimen holders (as shown in A, Fig. 1, and the left side of Fig. 2). The aluminum specimen holders and brass cap are constructed so that the upper specimen holder can be forced loose, turned over, and pressed down firmly against the specimen stage to a position represented by B, Fig. 1, and the right side of Fig. 2.


Author(s):  
Kathleen B. Reuter

The reaction rate and efficiency of piperazine to 1,4-diazabicyclo-octane (DABCO) depends on the Si/Al ratio of the MFI topology catalysts. The Al was shown to be the active site, however, in the Si/Al range of 30-200 the reaction rate increases as the Si/Al ratio increases. The objective of this work was to determine the location and concentration of Al to explain this inverse relationship of Al content with reaction rate.Two silicalite catalysts in the form of 1/16 inch SiO2/Al2O3 bonded extrudates were examined: catalyst A with a Si/Al of 83; and catalyst B, the acid/phosphate Al extracted form of catalyst A, with a Si/Al of 175. Five extrudates from each catalyst were fractured in the transverse direction and particles were obtained from the fracture surfaces near the center of the extrudate diameter. Particles were also obtained from the outside surfaces of five extrudates.


2020 ◽  
Vol 85 ◽  
pp. 47-58
Author(s):  
Y Jiang ◽  
Y Liu

Various studies have observed that increased nutrient supply promotes the growth of bloom-forming cyanobacteria, but only a limited number of studies have investigated the influence of increased nutrient supply on bloom-forming cyanobacteria at the proteomic level. We investigated the cellular and proteomic responses of Microcystis aeruginosa to elevated nitrogen and phosphorus supply. Increased supply of both nutrients significantly promoted the growth of M. aeruginosa and the synthesis of chlorophyll a, protein, and microcystins. The release of microcystins and the synthesis of polysaccharides negatively correlated with the growth of M. aeruginosa under high nutrient levels. Overexpressed proteins related to photosynthesis, and amino acid synthesis, were responsible for the stimulatory effects of increased nutrient supply in M. aeruginosa. Increased nitrogen supply directly promoted cyanobacterial growth by inducing the overexpression of the cell division regulatory protein FtsZ. NtcA, that regulates gene transcription related to both nitrogen assimilation and microcystin synthesis, was overexpressed under the high nitrogen condition, which consequently induced overexpression of 2 microcystin synthetases (McyC and McyF) and promoted microcystin synthesis. Elevated nitrogen supply induced the overexpression of proteins involved in gas vesicle organization (GvpC and GvpW), which may increase the buoyancy of M. aeruginosa. Increased phosphorus level indirectly affected growth and the synthesis of cellular substances in M. aeruginosa through the mediation of differentially expressed proteins related to carbon and phosphorus metabolism. This study provides a comprehensive description of changes in the proteome of M. aeruginosa in response to an increased supply of 2 key nutrients.


Author(s):  
Olga B. Ponomareva ◽  
Valeriya I. Orlova

This article presents a comprehensive analysis of the basic concepts that make up the conceptual sphere of the novel “Of Human Bondage” by W. S. Maugham. These concepts act as cognitive dominants of the linguistic consciousness of the protagonist’s linguistic personality in the work under study. The novelty of this research lies in the fact that it is performed within the framework of a new paradigm of linguistics — the cognitive linguistics, which involves the study of mental and linguistic representations of thought processes that occur during the perception of information. Moreover, the novel “Of Human Bondage” by W. S. Maugham has not attracted the attention of linguists-cognitologists previously, which adds to the novelty of this article. In addition, the present study provides a comprehensive description of the basic concepts making up the conceptual sphere of the novel. The linguistic methods of representing various concepts in the analyzed work are determined by the national, personal, cultural, and psychological aspects of Maugham’s thinking. The authors employ a communicative-cognitive methodological analysis proposed by N. S. Bolotnova involving the modeling of textual and intertextual semantic fields of artistic concepts and the analysis of the conceptual sphere of a literary text. The universal concepts RELIGION, LOVE, PASSION, THE MEANING OF LIFE, which constitute the conceptual sphere of the novel by W. S. Maugham “Of Human Bondage”, are analyzed. The main result of the study is that THE MEANING OF LIFE concept is universal, not individual, and it includes other universal concepts, such as RELIGION, LOVE, PASSION, THE MEANING OF LIFE, conceptual metaphors and metonyms, symbols, and other words-associates, which constitute the broad figurative and evaluative periphery of the conceptual sphere of the novel.


Author(s):  
Ginestra Bianconi

Defining the centrality of nodes and layers in multilayer networks is of fundamental importance for a variety of applications from sociology to biology and finance. This chapter presents the state-of-the-art centrality measures able to characterize the centrality of nodes, the influences of layers or the centrality of replica nodes in multilayer and multiplex networks. These centrality measures include modifications of the eigenvector centrality, Katz centrality, PageRank centrality and Communicability to the multilayer network scenario. The chapter provides a comprehensive description of the research of the field and discusses the main advantages and limitations of the different definitions, allowing the readers that wish to apply these techniques to choose the most suitable definition for his or her case study.


2013 ◽  
Vol 46 (4) ◽  
pp. 388-400 ◽  
Author(s):  
Agnieszka Dzioba ◽  
Elizabeth Skarakis-Doyle ◽  
Philip C. Doyle ◽  
Wenonah Campbell ◽  
Allyson D. Dykstra

Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1792
Author(s):  
Debashri Manna ◽  
Devanand Sarkar

Cancer development results from the acquisition of numerous genetic and epigenetic alterations in cancer cells themselves, as well as continuous changes in their microenvironment. The plasticity of cancer cells allows them to continuously adapt to selective pressures brought forth by exogenous environmental stresses, the internal milieu of the tumor and cancer treatment itself. Resistance to treatment, either inherent or acquired after the commencement of treatment, is a major obstacle an oncologist confronts in an endeavor to efficiently manage the disease. Resistance to chemotherapy, chemoresistance, is an important hallmark of aggressive cancers, and driver oncogene-induced signaling pathways and molecular abnormalities create the platform for chemoresistance. The oncogene Astrocyte elevated gene-1/Metadherin (AEG-1/MTDH) is overexpressed in a diverse array of cancers, and its overexpression promotes all the hallmarks of cancer, such as proliferation, invasion, metastasis, angiogenesis and chemoresistance. The present review provides a comprehensive description of the molecular mechanism by which AEG-1 promotes tumorigenesis, with a special emphasis on its ability to regulate chemoresistance.


Data ◽  
2021 ◽  
Vol 6 (6) ◽  
pp. 60
Author(s):  
Miguel A. Becerra ◽  
Catalina Tobón ◽  
Andrés Eduardo Castro-Ospina ◽  
Diego H. Peluffo-Ordóñez

This paper provides a comprehensive description of the current literature on data fusion, with an emphasis on Information Quality (IQ) and performance evaluation. This literature review highlights recent studies that reveal existing gaps, the need to find a synergy between data fusion and IQ, several research issues, and the challenges and pitfalls in this field. First, the main models, frameworks, architectures, algorithms, solutions, problems, and requirements are analyzed. Second, a general data fusion engineering process is presented to show how complex it is to design a framework for a specific application. Third, an IQ approach, as well as the different methodologies and frameworks used to assess IQ in information systems are addressed; in addition, data fusion systems are presented along with their related criteria. Furthermore, information on the context in data fusion systems and its IQ assessment are discussed. Subsequently, the issue of data fusion systems’ performance is reviewed. Finally, some key aspects and concluding remarks are outlined, and some future lines of work are gathered.


Sign in / Sign up

Export Citation Format

Share Document