Local modes

2002 ◽  
Vol 80 (12) ◽  
pp. 1635-1642 ◽  
Author(s):  
Bryan R Henry ◽  
Henrik G Kjaergaard

The historical background for the development of the local mode approach is reviewed, including the critical role of the radiation field. The harmonically coupled anharmonic oscillator model is described. Local modes have been used in the interpretation of XH stretching overtone spectra. These spectra can be used as sensitive probes of molecular properties such as bond length and molecular conformation. Examples of these spectral features are discussed. An intensity theory has been developed that permits the accurate calculation of relative and absolute overtone intensities. In molecules with low barriers to methyl rotation, torsional states contribute to the XH stretching band profile. A successful theoretical approach is presented that accounts for these effects and provides insight into the vibrational dynamics. The application of calculated local mode overtone spectra to atmospheric chemistry is discussed.Key words: local mode, overtone, vibrational intensity.

2021 ◽  
Vol 62 (2) ◽  
pp. 147-157
Author(s):  
Caleb Gordon ◽  
Hannah Malcolm

This article analyses the growing participation of UK Christians in climate initiatives over the last five years. In many cases, climate science is cited as a necessary consideration for the fulfilment of already-existing Christian commitments. This represents a significant shift in the ways UK Christians understand the role of dialogue between theology and the sciences; previous science and theology dialogue has usually been treated as an area of expert concern, primarily offering insight into apologetics or specific ethical problems. By contrast, the dialogue between climate science and theology has seen the emergence of non-technical leadership amid the expectation that climate science plays a critical role in re-examining the meaning of Christian life, both for individuals and as communities.


2013 ◽  
Author(s):  
◽  
Raksha Padaruth

This paper documents and evaluates the use of ceramics as an aesthetic architectural element in Durban from 1914-2012 with special reference to James Hall (1916-2006), Andrew Walford (b.1942) and Jane du Rand (b.1969). These artists were selected because their work demonstrates a wide range of the use of decorative tiles and mosaics as aesthetic elements in Durban architecture over a period of more than fifty years. Reference is made to the historical use of tiles and mosaics as aesthetic architectural elements in Durban from 1914-1955 in order to provide a context to an investigation and evaluation of the contribution of Hall, Walford and du Rand to the use of tiles and mosaics as an aesthetic architectural element in Durban. The paper begins by highlighting the importance of this study, discusses the role of ceramic architectural adornment and defines terminology for the purpose of this research. In addition an explanation of the research methodology used, research questions and literature review is provided. The study is contextualised through an overview of the historical background of the use of ceramics (tiles and mosaics) as an aesthetic element in architecture. The importance of the use of ceramic elements in relation to architecture, as well as the different techniques and methods of production, are highlighted and related to contemporary practice. The overview provides insight into how the use of ceramic elements in the past has influenced the approach of contemporary practice. My contribution to the use of mosaics as an aesthetic architectural element in Durban and my art practice, in the form of an installation titled passage is discussed and evaluated. The paper concludes by noting that the historical use of tiles and mosaics as aesthetic elements in architecture persists in contemporary art practice. However, the methods of tiled mosaic production and tiled mosaic techniques have been revolutionised extensively. It is evident that, the use of ceramics as an aesthetic element in Durban architecture reflects, both a strong European design influence and a distinctive local identity.


2018 ◽  
Author(s):  
David M. Kern ◽  
SeCheol Oh ◽  
Richard K. Hite ◽  
Stephen G. Brohawn

AbstractHypoosmotic conditions activate volume-regulated anion channels in vertebrate cells. These channels are formed by leucine-rich repeat-containing protein 8 (LRRC8) family members and contain LRRC8A in homo- or hetero-hexameric assemblies. Here we present single-particle cryo-electron microscopy structures of LRRC8A in complex with the inhibitor DCPIB reconstituted in lipid nanodiscs. DCPIB plugs the channel like a cork in a bottle - binding in the extracellular selectivity filter and sterically occluding ion conduction. Constricted and expanded structures reveal coupled dilation of cytoplasmic LRRs and the channel pore, suggesting a mechanism for channel gating by internal stimuli. Conformational and symmetry differences between LRRC8A structures determined in detergent micelles and lipid bilayers related to reorganization of intersubunit lipid binding sites demonstrate a critical role for the membrane in determining channel structure. These results provide insight into LRRC8 gating and inhibition and the role of lipids in the structure of an ionic-strength sensing ion channel.


2020 ◽  
Vol 34 (2) ◽  
pp. 99-110
Author(s):  
Thomas Gretton ◽  
Lindsey Blom ◽  
Dorice Hankemeier ◽  
Lawrence Judge

Preperformance routines are microlevel performance processes utilized by athletes to facilitate the attainment of an optimal state and enhance the chance for successful performance. Despite continued examination of these routines, only a small proportion of research has been directed toward the cognitive component of these routines. This study explored the cognitive component of elite high jumpers’ preperformance routines, and specifically the consistency of the cognitive content (i.e., psychological skills and strategies). Data were acquired over an 8-week high-jump season and subjected to inductive thematic analysis. Results revealed the consistent implementation of the cognitive content (e.g., visualization) but an inconsistent design of this content (i.e., the content of the visualization). Furthermore, results underline the critical role of high-jump coaches and an athlete’s need to be adaptable and competent in utilizing various types of preperformance routine. This study offers valuable insight into the complexities and inconsistencies of the cognitive component of high jumpers’ preperformance routines.


Science ◽  
2020 ◽  
Vol 369 (6510) ◽  
pp. 1477-1481 ◽  
Author(s):  
Yifei Du ◽  
Weidong An ◽  
Xing Zhu ◽  
Qi Sun ◽  
Jia Qi ◽  
...  

The 90S preribosome is a large, early assembly intermediate of small ribosomal subunits that undergoes structural changes to give a pre-40S ribosome. Here, we gained insight into this transition by determining cryo–electron microscopy structures of Saccharomyces cerevisiae intermediates in the path from the 90S to the pre-40S. The full transition is blocked by deletion of RNA helicase Dhr1. A series of structural snapshots revealed that the excised 5′ external transcribed spacer (5′ ETS) is degraded within 90S, driving stepwise disassembly of assembly factors and ribosome maturation. The nuclear exosome, an RNA degradation machine, docks on the 90S through helicase Mtr4 and is primed to digest the 3′ end of the 5′ ETS. The structures resolved between 3.2- and 8.6-angstrom resolution reveal key intermediates and the critical role of 5′ ETS degradation in 90S progression.


Author(s):  
Robert Bogue

Purpose The purpose of this paper is to provide an insight into how augmented reality (AR) technologies are being applied to robotics. Design/methodology/approach Following an introduction and a brief historical background to AR, this first provides examples of AR applications in robot programming. It then gives examples of recent research into AR-based robot teleoperation. Research activities involving the virtual fixtures (VF) technique are then discussed and finally, brief conclusions are drawn. Findings Because AR concepts were first investigated in the 1990s, applications involving robotics have been widely studied. Programming with the aid of AR devices, such as the HoloLens headset, can be simplified and AR methods, including the VF technique, can improve the accuracy and speed of teleoperation, manipulation and positional control tasks. They can also provide visual or haptic feedback which leads to more intuitive operation and significantly reduces the cognitive load on the operator. Originality/value This provides an insight into the growing role of AR in robotics by providing examples of recent research in a range of applications.


1976 ◽  
Vol 49 (4) ◽  
pp. 960-966 ◽  
Author(s):  
W. A. Thaler ◽  
D. J. Buckley

Abstract This investigation has provided insight into the critical role of solution properties on the course of cationic polymerization and has led to a technique for reconciling the opposing demands for synthesis of isoolefin-diene copolymers both free from gel and high in molecular weight. By this technique, the synthesis of a broad range of intermediate-unsaturation elastomers of quality has been realized.


2021 ◽  
Vol 12 ◽  
Author(s):  
Panpan Chang ◽  
Hao Li ◽  
Hui Hu ◽  
Yongqing Li ◽  
Tianbing Wang

Autophagy fights against harmful stimuli and degrades cytosolic macromolecules, organelles, and intracellular pathogens. Autophagy dysfunction is associated with many diseases, including infectious and inflammatory diseases. Recent studies have identified the critical role of the NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasomes activation in the innate immune system, which mediates the secretion of proinflammatory cytokines IL-1β/IL-18 and cleaves Gasdermin D to induce pyroptosis in response to pathogenic and sterile stimuli. Accumulating evidence has highlighted the crosstalk between autophagy and NLRP3 inflammasome in multifaceted ways to influence host defense and inflammation. However, the underlying mechanisms require further clarification. Histone deacetylase 6 (HDAC6) is a class IIb deacetylase among the 18 mammalian HDACs, which mainly localizes in the cytoplasm. It is involved in two functional deacetylase domains and a ubiquitin-binding zinc finger domain (ZnF-BUZ). Due to its unique structure, HDAC6 regulates various physiological processes, including autophagy and NLRP3 inflammasome, and may play a role in the crosstalk between them. In this review, we provide insight into the mechanisms by which HDAC6 regulates autophagy and NLRP3 inflammasome and we explored the possibility and challenges of HDAC6 in the crosstalk between autophagy and NLRP3 inflammasome. Finally, we discuss HDAC6 inhibitors as a potential therapeutic approach targeting either autophagy or NLRP3 inflammasome as an anti-inflammatory strategy, although further clarification is required regarding their crosstalk.


2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Ruanmei Sheng ◽  
Xiaoming Zhong ◽  
Zhiwen Yang ◽  
Xuemin Wang

Neutrophils play a critical role in innate immune defense and directly contribute to infectious and autoimmune ailments. Great efforts are underway to better understand the nature of neutrophilic inflammation. Of note, CARD9, a myeloid cell-specific signaling protein that mainly expresses in macrophages and dendritic cells, is also present in neutrophils, emerging as a critical mediator for intercellular communication. CARD9–deficiency neutrophils display an increased susceptibility to fungal infection that primarily localize to the central nervous system, subcutaneous, and skin tissue. Additionally, CARD9–deficiency neutrophils are associated with some autoimmune diseases and even provide protection against a few bacteria. Here, the review summarizes recent preclinical and clinical advances that have provided a novel insight into the pathogenesis of CARD9 deficiency in neutrophils.


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