scholarly journals A Central Role for Genetics in Plant Biology

2021 ◽  
Vol 72 (1) ◽  
pp. 1-16
Author(s):  
Maarten Koornneef
Keyword(s):  
Natural Variation ◽  
Plant Biology ◽  
Model Species ◽  
Plant Breeder ◽  
Physiological Characterization ◽  
The Past ◽  
Area Of Interest ◽  
Integrated Study ◽  
Main Model

This article describes my involvement in the development of genetics as an essential tool in the integrated study of plant biology. My research comes from a strong background in plant genetics based on my education as a plant breeder at Wageningen University and collaborations with plant physiologists and molecular geneticists in Wageningen and the wider scientific community. It initially involved the isolation and physiological characterization of mutants defective in biosynthesis or mode of action of plant hormones, photoreceptors and traits such as flowering time in both Arabidopsis and tomato. I also generated a genetic map of Arabidopsis. Subsequently, the exploitation of natural variation became a main area of interest, including the molecular identification of underlying genetic differences. The integration of various disciplines and the adoption of Arabidopsis as a main model species contributed strongly to the impressive progress in our knowledge of plant biology over the past 40 years.

Review. Solvothermal Synthesis and Structure of Chalcogenidoarsenate Anions

2010 ◽  
Vol 65 (8) ◽  
pp. 918-936 ◽  
Author(s):  
Anna Kromm ◽  
Tobias van Almsick ◽  
William S. Sheldrick
Keyword(s):  
Transition Metal ◽  
Rich Variety ◽  
The Past ◽  
Coordination Sites ◽  
Area Of Interest ◽  
Metal Atoms ◽  
New Compounds ◽  
Solvothermal Conditions ◽  
Structural Aspects

A rich variety of chalcogenidoarsenate anions and ligands have been prepared under mild solvothermal conditions in strongly polarizing solvents such as water, methanol and amines in the temperature range 100 - 200 ◦C. This review covers synthetic and structural aspects of such species ASxEyz− with particular emphasis being placed on the trends and differences observed for E = S, Se, Te and on developments within the past decade. These include the preparation of quaternary Main Group element chalcogenidoarsenates(III) such as Cs3AsGeSe5 and polymeric selenidoarsenates(II, III) such as Cs2As4Se6. A currently expanding area of interest involves the employment of transition metal-polyamine or -polyimine fragments such as {Mn(tren)}2+ or {Mn(terpy)}2+ as structuredirecting agents. The metal atoms of such cations can be connected to the terminal chalcogen atoms of oligomeric or polymeric anions AsxEy z− to prevent their further condensation or can be directly incorporated into anionic or neutral networks when at least two free coordination sites are available in the fragment. This strategy has led to the characterization of novel ligands including cyclo- [As4S8]4−, As2Se62−, As2Se64− and 1∞[As4Se72−]. The syntheses and structures of the new compounds Cs5As5Se9 and Cs[{Mn(trien)}(AsSe4-K2Se)] ・CH3OH are also presented. Whereas the former phase contains infinite selenidoarsenate(II,III) chains 1∞[As5Se95−], the [{Mn(trien)}(AsSe4)]− anion of the latter compound represents the first example of a transition metal-containing ternary selenidoarsenate( V)

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

Ionic Liquids for the Synthesis of Five-Membered N,N-, N,N,N- and N,N,N,NHeterocycles

2019 ◽  
Vol 23 (11) ◽  
pp. 1214-1238 ◽  
Author(s):  
Navjeet Kaur ◽  
Pranshu Bhardwaj ◽  
Meenu Devi ◽  
Yamini Verma ◽  
Neha Ahlawat ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Organic Synthesis ◽  
Heterocyclic Compounds ◽  
Reaction Medium ◽  
Environmental Issues ◽  
Organic Reaction ◽  
Environment Friendly ◽  
The Past ◽  
Area Of Interest ◽  
Major Subject

Due to special properties of ILs (Ionic Liquids) like their wide liquid range, good solvating ability, negligible vapour pressure, non-inflammability, environment friendly medium, high thermal stability, easy recycling and rate promoters etc. they are used in organic synthesis. The investigation for the replacement of organic solvents in organic synthesis is a growing area of interest due to increasing environmental issues. Therefore, ionic liquids have attracted the attention of chemists and act as a catalyst and reaction medium in organic reaction with high activity. There is no doubt that ionic liquids have become a major subject of study for modern chemistry. In comparison to traditional processes the use of ionic liquids resulted in improved, complimentary or alternative selectivities in organic synthesis. The present manuscript reported the synthesis of multiple nitrogen containing five-membered heterocyclic compounds using ionic liquids. This review covered interesting discoveries in the past few years.

‘The Wretch of To-day, may be happy To-morrow’

2017 ◽  
Author(s):  
Sarah Lloyd
Keyword(s):  
Emotional Experience ◽  
The Past

This chapter explores what we can know about the conceptualization and representation of by poorer Britons. It draws on ‘pauper letters’ to parish authorities, written tactically, and on autobiographies and letters composed by the relatively poor, noting echoes of the characterization of happiness by elite social commentators. It draws attention to a growing interest (linked to the development of the concept of nostalgia) in the emotional charge that could be derived from reflection on emotional experience as people contrasted past happiness with present misery, or vice versa. While reading such accounts may lead us to think that we are penetrating the interior lives of marginal people in the past, Lloyd suggests that our response is probably coloured by the fact that we are heirs to these ways of conceptualizing and representing experience. We need to work harder to glean insight from earlier ways of representing happiness and suffering.

The Problem of Divine Hiddenness

2018 ◽  
Author(s):  
Michael C. Rea
Keyword(s):  
Problem Of Evil ◽  
Philosophical Discussion ◽  
Detailed Characterization ◽  
The Past ◽  
Divine Hiddenness ◽  
The Problem Of Evil ◽  
The Relationship

This chapter provides a detailed characterization of the various meanings of the term “divine hiddenness,” carefully and rigorously articulates the version of the problem of divine hiddenness that has dominated contemporary philosophical discussion for the past twenty-five years, and then explains the relationship between that problem and the problem of evil.

scholarly journals Molecular Pathogenesis of Hodgkin Lymphoma: Past, Present, Future

2020 ◽  
Vol 21 (18) ◽  
pp. 6623 ◽  
Author(s):  
Marc Bienz ◽  
Salima Ramdani ◽  
Hans Knecht
Keyword(s):  
Immune System ◽  
Targeted Therapy ◽  
Signaling Pathways ◽  
Hodgkin Lymphoma ◽  
Genetic Instability ◽  
Host Immune System ◽  
Cellular Interactions ◽  
Classical Hodgkin Lymphoma ◽  
The Past

Our understanding of the tumorigenesis of classical Hodgkin lymphoma (cHL) and the formation of Reed–Sternberg cells (RS-cells) has evolved drastically in the last decades. More recently, a better characterization of the signaling pathways and the cellular interactions at play have paved the way for new targeted therapy in the hopes of improving outcomes. However, important gaps in knowledge remain that may hold the key for significant changes of paradigm in this lymphoma. Here, we discuss the past, present, and future of cHL, and review in detail the more recent discoveries pertaining to genetic instability, anti-apoptotic signaling pathways, the tumoral microenvironment, and host-immune system evasion in cHL.

Molecular and physiological characterization of Arabidopsis‐Colletotrichum gloeosporioides pathosystem

2021 ◽  
Author(s):  
Mengze Gao ◽  
Miting Wan ◽  
Liyun Yang ◽  
Meng Zhao ◽  
Xiaojin Liu ◽  
...  
Keyword(s):  
Colletotrichum Gloeosporioides ◽  
Physiological Characterization

scholarly journals Synthesis and Characterization of Store-Operated Calcium Entry Inhibitors Active in the Submicromolar Range

2020 ◽  
Vol 21 (24) ◽  
pp. 9777
Author(s):  
Camille Le Guilcher ◽  
Tomas Luyten ◽  
Jan B. Parys ◽  
Mathieu Pucheault ◽  
Olivier Dellis
Keyword(s):  
Cell Activation ◽  
Interleukin 2 ◽  
Calcium Entry ◽  
Ip3 Receptors ◽  
Excitable Cells ◽  
Cellular Targets ◽  
Entry Inhibitors ◽  
The Past ◽  
Store Operated Calcium Entry

The store-operated calcium entry, better known as SOCE, forms the main Ca2+ influx pathway in non-excitable cells, especially in leukocytes, where it is required for cell activation and the immune response. During the past decades, several inhibitors were developed, but they lack specificity or efficacy. From the non-specific SOCE inhibitor 2-aminoethyl diphenylborinate (2-APB), we synthetized 16 new analogues by replacing/modifying the phenyl groups. Among them, our compound P11 showed the best inhibitory capacity with a Ki ≈ 75 nM. Furthermore, below 1 µM, P11 was devoid of any inhibitory activity on the two other main cellular targets of 2-APB, the IP3 receptors, and the SERCA pumps. Interestingly, Jurkat T cells secrete interleukin-2 under phytohemagglutinin stimulation but undergo cell death and stop IL-2 synthesis when stimulated in the presence of increasing P11 concentrations. Thus, P11 could represent the first member of a new and potent family of immunosuppressors.

scholarly journals Theoretical and Empirical Characterization of Water as a Factor: Examples and Related Issues with the World Trade Model

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 459
Author(s):  
Ignacio Cazcarro ◽  
Albert E. Steenge
Keyword(s):  
World Trade ◽  
Low Cost ◽  
Virtual Water ◽  
Considerable Change ◽  
Water Research ◽  
Trade Model ◽  
The World ◽  
Main Model ◽  
Selection Of

This article originates from the theoretical and empirical characterization of factors in the World Trade Model (WTM). It first illustrates the usefulness of this type of model for water research to address policy questions related to virtual water trade, water constraints and water scarcity. It also illustrates the importance of certain key decisions regarding the heterogeneity of water and its relation to the technologies being employed and the prices obtained. With regard to WTM, the global economic input–output model in which multiple technologies can produce a “homogeneous output”, it was recently shown that two different mechanisms should be distinguished by which multiple technologies can arise, i.e., from “technology-specific” or from “shared” factors, which implies a mechanism-specific set of prices, quantities and rents. We discuss and extend these characterizations, notably in relation to the real-world characterization of water as a factor (for which we use the terms technology specific, fully shared and “mixed”). We propose that the presence of these separate mechanisms results in the models being sensitive to relatively small variations in specific numerical values. To address this sensitivity, we suggest a specific role for specific (sub)models or key choices to counter unrealistic model outcomes. To support our proposal we present a selection of simulations for aggregated world regions, and show how key results concerning quantities, prices and rents can be subject to considerable change depending on the precise definitions of resource endowments and the technology-specificity of the factors. For instance, depending on the adopted water heterogeneity level, outcomes can vary from relatively low-cost solutions to higher cost ones and can even reach infeasibility. In the main model discussed here (WTM) factor prices are exogenous, which also contributes to the overall numerical sensitivity of the model. All this affects to a large extent our interpretation of the water challenges, which preferably need to be assessed in integrated frameworks, to account for the main socioeconomic variables, technologies and resources.

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