Rational Design of Layered Perovskites through the Organic Cation Selection for Emission Tunability

Hydride ion conduction in layered perovskites is of great interest for sustainable-energy applications. In this report we study Ba2ScHO3, a recently synthesized oxyhydride with an unusual anion ordering, using a multifaceted density functional theory approach involving both transition state calculations and molecular dynamics simulations. Beyond simply identifying the key ion migration pathways, we perform detailed analysis of transition states and identify key interactions which drive trends in ionic mobility. Our key findings are that ionic mobility is, remarkably, independent of hydride-oxide disorder, the dominant migration pathway changes under pressure, and a reduction in A-site cation size accelerates hydride diffusion. Local structural flexibility along migration pathways is understood in terms of dimensionality and ionic size, and we thus identify crystal engineering principles for rational design of ion conductors. On the basis of our new insights into these materials, we predict that Sr2ScHO3 will show improved conductivity over existing analogues.

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RNA virus attenuation by codon pair deoptimisation is an artefact of increases in CpG/UpA dinucleotide frequencies

eLife ◽

10.7554/elife.04531 ◽

2014 ◽

Vol 3 ◽

Cited By ~ 103

Author(s):

Fiona Tulloch ◽

Nicky J Atkinson ◽

David J Evans ◽

Martin D Ryan ◽

Peter Simmonds

Keyword(s):

Virus Replication ◽

Rational Design ◽

Rna Virus ◽

Safety Evaluation ◽

Translation Efficiency ◽

Innate Immune Responses ◽

Live Virus ◽

Codon Pair ◽

Selection For ◽

Virus Genomes

Mutating RNA virus genomes to alter codon pair (CP) frequencies and reduce translation efficiency has been advocated as a method to generate safe, attenuated virus vaccines. However, selection for disfavoured CPs leads to unintended increases in CpG and UpA dinucleotide frequencies that also attenuate replication. We designed and phenotypically characterised mutants of the picornavirus, echovirus 7, in which these parameters were independently varied to determine which most influenced virus replication. CpG and UpA dinucleotide frequencies primarily influenced virus replication ability while no fitness differences were observed between mutants with different CP usage where dinucleotide frequencies were kept constant. Contrastingly, translation efficiency was unaffected by either CP usage or dinucleotide frequencies. This mechanistic insight is critical for future rational design of live virus vaccines and their safety evaluation; attenuation is mediated through enhanced innate immune responses to viruses with elevated CpG/UpA dinucleotide frequencies rather the viruses themselves being intrinsically defective.

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Design Considerations for Propellers in a Cavitating Environment

Marine Technology and SNAME News ◽

10.5957/mt1.1978.15.2.144 ◽

1978 ◽

Vol 15 (02) ◽

pp. 144-178 ◽

Cited By ~ 3

Author(s):

Donald L. Blount ◽

David L. Fox

Keyword(s):

Rational Design ◽

Computation Time ◽

Design Practice ◽

Good Balance ◽

Design Considerations ◽

Performance Predictions ◽

Blade Section ◽

Selection For ◽

Thrust And Torque ◽

Propeller Thrust

Cavitation adds a dimension to propeller operation that necessitates rational design practice to approach a good balance of craft requirements. This paper discusses propeller characteristic format to reduce the computation time to make performance predictions and propeller selection for partially and fully cavitating conditions. In addition, maximum propeller thrust and torque loading limits are defined for four different blade section shapes, including recommended design limits. Discussers Jim W. Bordeaux Mark Oaks

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New Development of Biomarkers for Gastrointestinal Cancers: From Neoplastic Cells to Tumor Microenvironment

Biomedicines ◽

10.3390/biomedicines6030087 ◽

2018 ◽

Vol 6 (3) ◽

pp. 87 ◽

Cited By ~ 1

Author(s):

Jiajia Zhang ◽

Shafat Quadri ◽

Christopher Wolfgang ◽

Lei Zheng

Keyword(s):

Tumor Microenvironment ◽

Rational Design ◽

Response To Treatment ◽

Liquid Biopsies ◽

Gastrointestinal Malignancies ◽

Immune Biomarkers ◽

New Development ◽

Selection For ◽

Monitor Treatment Response ◽

Tumor Genome

Biomarkers refer to a plethora of biological characteristics that can be quantified to facilitate cancer diagnosis, forecast the prognosis of disease, and predict a response to treatment. The identification of objective biomarkers is among the most crucial steps in the realization of individualized cancer care. Several tumor biomarkers for gastrointestinal malignancies have been applied in the clinical setting to help differentiate between cancer and other conditions, facilitate patient selection for targeted therapies, and to monitor treatment response and recurrence. With the coming of the immunotherapy age, the need for a new development of biomarkers that are indicative of the immune response to tumors are unprecedentedly urgent. Biomarkers from the tumor microenvironment, tumor genome, and signatures from liquid biopsies have been explored, but the majority have shown a limited prognostic or predictive value as single biomarkers. Nevertheless, use of multiplex biomarkers has the potential to provide a significantly increased diagnostic accuracy compared to traditional single biomarker. A comprehensive analysis of immune-biomarkers is needed to reveal the dynamic and multifaceted anti-tumor immunity and thus imply for the rational design of assays and combinational strategies.

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Improving Hydride Conductivity in Layered Perovskites via Crystal Engineering

10.26434/chemrxiv.12730553 ◽

2020 ◽

Author(s):

Harry W. T. Morgan ◽

Harry J. Stroud ◽

Neil Allan

Keyword(s):

Crystal Engineering ◽

Density Functional ◽

Rational Design ◽

Ionic Mobility ◽

Theory Approach ◽

Ion Migration ◽

Energy Applications ◽

Migration Pathway ◽

Migration Pathways ◽

Layered Perovskites

Hydride ion conduction in layered perovskites is of great interest for sustainable-energy applications. In this report we study Ba2ScHO3, a recently synthesized oxyhydride with an unusual anion ordering, using a multifaceted density functional theory approach involving both transition state calculations and molecular dynamics simulations. Beyond simply identifying the key ion migration pathways, we perform detailed analysis of transition states and identify key interactions which drive trends in ionic mobility. Our key findings are that ionic mobility is, remarkably, independent of hydride-oxide disorder, the dominant migration pathway changes under pressure, and a reduction in A-site cation size accelerates hydride diffusion. Local structural flexibility along migration pathways is understood in terms of dimensionality and ionic size, and we thus identify crystal engineering principles for rational design of ion conductors. On the basis of our new insights into these materials, we predict that Sr2ScHO3 will show improved conductivity over existing analogues.

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Enhanced Out-of-Plane Conductivity and Photovoltaic Performance in n = 1 Layered Perovskites through Organic Cation Design

Journal of the American Chemical Society ◽

10.1021/jacs.8b03659 ◽

2018 ◽

Vol 140 (23) ◽

pp. 7313-7323 ◽

Cited By ~ 80

Author(s):

James V. Passarelli ◽

Daniel J. Fairfield ◽

Nicholas A. Sather ◽

Mark P. Hendricks ◽

Hiroaki Sai ◽

...

Keyword(s):

Organic Cation ◽

Photovoltaic Performance ◽

Out Of Plane ◽

Layered Perovskites

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Molecular insights on the dynamic stability of peptide nucleic acid functionalized carbon and boron nitride nanotubes

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05759b ◽

2021 ◽

Vol 23 (1) ◽

pp. 219-228

Author(s):

Nabanita Saikia ◽

Mohamed Taha ◽

Ravindra Pandey

Keyword(s):

Nucleic Acid ◽

Boron Nitride ◽

Nucleic Acids ◽

Dynamic Stability ◽

Peptide Nucleic Acid ◽

Rational Design ◽

Peptide Nucleic Acids ◽

Boron Nitride Nanotubes ◽

Molecular Hybrids ◽

Single Wall Nanotubes

The rational design of self-assembled nanobio-molecular hybrids of peptide nucleic acids with single-wall nanotubes rely on understanding how biomolecules recognize and mediate intermolecular interactions with the nanomaterial's surface.

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Optimizing electron density of nickel sulfide electrocatalysts through sulfur vacancy engineering for alkaline hydrogen evolution

Journal of Materials Chemistry A ◽

10.1039/d0ta05594h ◽

2020 ◽

Vol 8 (35) ◽

pp. 18207-18214

Author(s):

Dongbo Jia ◽

Lili Han ◽

Ying Li ◽

Wenjun He ◽

Caichi Liu ◽

...

Keyword(s):

Hydrogen Evolution ◽

Electron Density ◽

Rational Design ◽

Nickel Sulfide ◽

Catalytic Performance ◽

Sulfide Catalysts ◽

Sulfur Vacancy

A novel, rational design for porous S-vacancy nickel sulfide catalysts with remarkable catalytic performance for alkaline HER.

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Framework for Selecting Vocabulary for Preliterate Children Who Use Augmentative and Alternative Communication

American Journal of Speech-Language Pathology ◽

10.1044/2019_ajslp-18-0041 ◽

2019 ◽

Vol 28 (3) ◽

pp. 1000-1009

Author(s):

Allison Bean ◽

Lindsey Paden Cargill ◽

Samantha Lyle

Keyword(s):

Language Impairment ◽

Augmentative And Alternative Communication ◽

Developmentally Appropriate ◽

School Age Children ◽

Alternative Communication ◽

School Based ◽

Selection For ◽

Nonverbal Children ◽

Grammatical Structures ◽

Insufficient Knowledge

Purpose Nearly 50% of school-based speech-language pathologists (SLPs) provide services to school-age children who use augmentative and alternative communication (AAC). However, many SLPs report having insufficient knowledge in the area of AAC implementation. The objective of this tutorial is to provide clinicians with a framework for supporting 1 area of AAC implementation: vocabulary selection for preliterate children who use AAC. Method This tutorial focuses on 4 variables that clinicians should consider when selecting vocabulary: (a) contexts/environments where the vocabulary can be used, (b) time span during which the vocabulary will be relevant, (c) whether the vocabulary can elicit and maintain interactions with other people, and (d) whether the vocabulary will facilitate developmentally appropriate grammatical structures. This tutorial focuses on the role that these variables play in language development in verbal children with typical development, verbal children with language impairment, and nonverbal children who use AAC. Results Use of the 4 variables highlighted above may help practicing SLPs select vocabulary that will best facilitate language acquisition in preliterate children who use AAC.

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