Showing papers by "King Abdullah University of Science and Technology published in 2023"

Non‐Flammable Electrolyte Enables High‐Voltage and Wide‐Temperature Lithium‐Ion Batteries with Fast Charging

Abstract: Electrolyte design has become ever more important to enhance the performance of lithium-ion batteries (LIBs). However, the flammability issue and high reactivity of the conventional electrolytes remain a major problem, especially when the LIBs are operated at high voltage and extreme temperatures. Herein, we design a novel non-flammable fluorinated ester electrolyte that enables high cycling stability in wide-temperature variations (e.g., -50 °C-60 °C) and superior power capability (fast charge rates up to 5.0 C) for the graphite||LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) battery at high voltage (i.e., >4.3 V vs. Li/Li+ ). Moreover, this work sheds new light on the dynamic evolution and interaction among the Li+ , solvent, and anion at the molecular level. By elucidating the fundamental relationship between the Li+ solvation structure and electrochemical performance, we can facilitate the development of high-safety and high-energy-density batteries operating in harsh conditions.

Alkaloids as potential antivirals. A comprehensive review

Abstract: Alkaloids are a diverse group of natural phytochemicals. These phytochemicals in plants provide them protection against pests, and herbivorous organisms and also control their development. Numerous of these alkaloids have a variety of biological effects, and some have even been developed into medications with different medicinal properties. This review aims to provide a broad overview of the numerous naturally occurring alkaloids (isolated from both terrestrial and aquatic species) along with synthetically produced alkaloid compounds having prominent antiviral properties. Previous reviews on this subject have focused on the biological actions of both natural and synthetic alkaloids, but they have not gone into comprehensive detail about their antiviral properties. We reviewed here several antiviral alkaloids that have been described in the literature in different investigational environments i.e. (in-vivo, in-ovo, in-vitro, and in-silico), and found that these alkaloid compounds have significant antiviral properties against several infectious viruses. These alkaloids repressed and targeted various important stages of viral infection at non-toxic doses while some of the alkaloids reported here also exhibited comparable inhibitory activities to commercially used drugs. Overall, these anti-viral effects of alkaloids point to a high degree of specificity, implying that they could serve as effective and safe antiviral medicines if further pursued in medicinal and pharmacological investigations.

Flame Synthesis of Carbon and Metal-Oxide Nanoparticles: Flame Types, Effects of Combustion Parameters on Properties and Measurement Methods

Abstract: Carbon and metal-oxide nanoparticles (NP) are currently synthesized worldwide for various applications in the solar-energy, optical, pharmaceutical, and biomedical industries, among many others. Gas phase methods comprise flame synthesis and flame spray pyrolysis (FSP), which provide high efficiency, low cost, and the possibility of large-scale applications. The variation of combustion operation parameters exerts significant effects on the properties of the NPs. An analysis of the latest research results relevant to NP flame synthesis can provide new insight into the optimization of these methods and the development of these techniques for a large scale. This review offers insight into the current status of flame synthesis for carbon and metal-oxide NPs—specifically containing analysis and comparison of the most common carbon and metal-oxide NP production techniques. The burner configurations used at the laboratory scale and large scale are also discussed, followed by the assessment of the influence of combustion parameters on the properties of NPs. Finally, the features of the measurement techniques applied for determining NP properties were described.

Synthetic biology open language (SBOL) version 3.1.0

Abstract: Abstract Synthetic biology builds upon genetics, molecular biology, and metabolic engineering by applying engineering principles to the design of biological systems. When designing a synthetic system, synthetic biologists need to exchange information about multiple types of molecules, the intended behavior of the system, and actual experimental measurements. The Synthetic Biology Open Language (SBOL) has been developed as a standard to support the specification and exchange of biological design information in synthetic biology, following an open community process involving both bench scientists and scientific modelers and software developers, across academia, industry, and other institutions. This document describes SBOL 3.1.0, which improves on version 3.0.0 by including a number of corrections and clarifications as well as several other updates and enhancements. First, this version includes a complete set of validation rules for checking whether documents are valid SBOL 3. Second, the best practices section has been moved to an online repository that allows for more rapid and interactive of sharing these conventions. Third, it includes updates based upon six community approved enhancement proposals. Two enhancement proposals are related to the representation of an object’s namespace. In particular, the Namespace class has been removed and replaced with a namespace property on each class. Another enhancement is the generalization of the CombinatorialDeriviation class to allow direct use of Features and Measures . Next, the Participation class now allow Interactions to be participants to describe higher-order interactions. Another change is the use of Sequence Ontology terms for Feature orientation . Finally, this version of SBOL has generalized from using Unique Reference Identifiers (URIs) to Internationalized Resource Identifiers (IRIs) to support international character sets.

Genome‐wide identification and characterization of exapted transposable elements in the large genome of sunflower ( <i>Helianthus annuus</i> L.)

Abstract: Transposable elements (TEs) are an important source of genome variability, playing many roles in the evolution of eukaryotic species. Besides well-known phenomena, TEs may undergo the exaptation process and generate the so-called exapted transposable element genes (ETEs). Here we present a genome-wide survey of ETEs in the large genome of sunflower (Helianthus annuus L.), in which the massive amount of TEs, provides a significant source for exaptation. A library of sunflower TEs was used to build TE-specific Hidden Markov Model profiles, to search for all available sunflower gene products. In doing so, 20 016 putative ETEs were identified and further investigated for the characteristics that distinguish TEs from genes, leading to the validation of 3530 ETEs. The analysis of ETEs transcription patterns under different stress conditions showed a differential regulation triggered by treatments mimicking biotic and abiotic stress; furthermore, the distribution of functional domains of differentially regulated ETEs revealed a relevant presence of domains involved in many aspects of cellular functions. A comparative genomic investigation was performed including species representative of Asterids and appropriate outgroups: the bulk of ETEs that resulted were specific to the sunflower, while few ETEs presented orthologues in the genome of all analyzed species, making the hypothesis of a conserved function. This study highlights the crucial role played by exaptation, actively contributing to species evolution.

Tuning Rate of Strategy Revision in Population Games

Abstract: We investigate a multi-agent decision problem in population games where each agent in a population makes a decision on strategy selection and revision to engage in repeated games with others. The strategy revision is subject to time delays which represent the time it takes for an agent revising its strategy needs to spend before it can adopt a new strategy and return back to the game. We discuss the effect of the time delays on long-term behavior of the agents’ strategy revision. In particular, when the time delays are large, the strategy revision would exhibit oscillation and the agents spend substantial time in "transitioning" between different strategies, which prevents the agents from attaining the Nash equilibrium of the game. As a main contribution of the paper, we propose an algorithm that tunes the rate of the agents’ strategy revision and show such tuning approach ensures convergence to the Nash equilibrium. We validate our analytical results using simulations.

Preferential Pyrolysis Construction of Carbon Anodes with 8400 h Lifespan for High‐Energy‐Density K‐ion Batteries

Abstract: Carbonaceous materials are promising anodes for practical potassium-ion batteries, but fail to meet the requirements for durability and high capacities at low potentials. Herein, we constructed a durable carbon anode for high-energy-density K-ion full cells by a preferential pyrolysis strategy. Utilizing S and N volatilization from a π–π stacked supermolecule, the preferential pyrolysis process introduces low-potential active sites of sp2 hybridized carbon and carbon vacancies, endowing a low-potential “vacancy-adsorption/intercalation” mechanism. The as-prepared carbon anode exhibits a high capacity of 384.2 mAh g−1 (90 % capacity locates below 1 V vs. K/K+), which contributes to a high energy density of 163 Wh kg−1 of K-ion full battery. Moreover, abundant vacancies of carbon alleviate volume variation, boosting the cycling stability over 14 000 cycles (8400 h). Our work provides a new synthesis approach for durable carbon anodes of K-ion full cells with high energy densities.

Architectural Structures from Quad Meshes with Planar Parameter Lines

Abstract: We address the computational design of architectural structures which are based on a grid of intersecting beams that are aligned with the parameter lines of a quad mesh. While previous work mainly put a planarity constraint onto the faces of the mesh, we focus on the planarity of long-range supporting beams which follow selected polylines in the underlying mesh. In addition to that, we impose further constraints including planarity of faces, right node angles and static equilibrium, and discuss in which way these may be combined. Some of the studied meshes are discrete counterparts of certain well-known surfaces in classical geometry, whose knowledge is helpful for initializing the proposed optimization algorithms.

Insights into the drivers and spatio-temporal trends of extreme wildfires with statistical deep-learning

Abstract: Extreme wildfires continue to be a significant cause of human death and biodiversity destruction across the globe, with recent worrying trends in their activity (i.e., occurrence and spread) suggesting that wildfires are likely to be highly impacted by climate change. In order to facilitate appropriate risk mitigation for extreme wildfires, it is imperative to identify their main drivers and assess their spatio-temporal trends, with a view to understanding the impacts of global warming on fire activity. To this end, we analyse monthly burnt area due to wildfires using a hybrid statistical deep-learning framework that exploits extreme value theory and quantile regression. Three study regions are considered: the contiguous U.S., Mediterranean Europe and Australia.

Isolated Electron Trap‐Induced Charge Accumulation for Efficient Photocatalytic Hydrogen Production

Abstract: The solar-driven evolution of hydrogen from water using particulate photocatalysts is considered one of the most economical and promising protocols for achieving a stable supply of renewable energy. However, the efficiency of photocatalytic water splitting is far from satisfactory due to the sluggish electron-hole pair separation kinetics. Herein, isolated Mo atoms in a high oxidation state have been incorporated into the lattice of Cd0.5Zn0.5S ([email protected]) nanorods, which exhibit photocatalytic hydrogen evolution rate of 11.32 mmol g−1 h−1 (226.4 μmol h−1; catalyst dosage 20 mg). Experimental and theoretical simulation results imply that the highly oxidized Mo species lead to mobile-charge imbalances in CZS and induce the directional photogenerated electrons transfer, resulting in effectively inhibited electron-hole recombination and greatly enhanced photocatalytic efficiency.

Cultivation of the polyextremophile<i>Cyanidioschyzon merolae</i>10D during summer conditions on the coast of the Red Sea and its adaptation to hypersaline sea water

Abstract: Abstract The west coast of Saudi Arabia borders the Red Sea, which maintains high average temperatures and increased salinity compared to other seas or oceans. Summer conditions in the Arabian Peninsula may exceed the temperature tolerance of most currently cultivated microalgae. The Cyanidiales are polyextremophilic red algae whose native habitats are at the edges of acidic hot springs. Cyanidioschyzon merolae 10D has recently emerged as an interesting model organism capable of high-cell density cultivation on pure CO 2 with optimal growth at 42 °C and low pH between 0.5-2. C. merolae biomass has an interesting macromolecular composition, is protein rich, and contains valuable bio-products like heat-stable phycocyanin, carotenoids, β-glucan, and starch. Here, photobioreactors were used to model C. merolae 10D growth performance in simulated environmental conditions of the mid-Red Sea coast across four seasons, it was then grown at various scales outdoors in Thuwal, Saudi Arabia during the Summer of 2022. We show that C. merolae 10D is amenable to cultivation with industrial-grade nutrient and CO 2 inputs outdoors in this location and that its biomass is relatively constant in biochemical composition across culture conditions. We also show the adaptation of C. merolae 10D to high salinity levels of those found in Red Sea waters and conducted further modeled cultivations in nutrient enriched local sea water. It was determined that salt-water adapted C. merolae 10D could be cultivated with reduced nutrient inputs in local conditions. The results presented here indicate this may be a promising alternative species for algal bioprocesses in outdoor conditions in extreme desert summer environments.

Linker histone H1 modulates defense priming and immunity in plants

Abstract: Abstract Linker H1 histones play an important role in animal and human pathogenesis, but their function in plant immunity is poorly understood. Here, we analyzed mutants of the three canonical variants of Arabidopsis H1 histones, namely H1.1, H1.2 and H1.3. We observed that double h1.1h1.2 and triple h1.1h1.2h1.3 (3h1) mutants were resistant to Pseudomonas syringae and Botrytis cinerea infections. Transcriptome analysis of 3h1 mutant plants showed H1s play a key role in regulating the expression of early and late defense genes upon pathogen challenge. Moreover, 3h1 mutant plants showed enhanced production of reactive oxygen species and activation of mitogen activated protein kinases upon pathogen-associated molecular pattern (PAMP) treatment. However, 3h1 mutant plants were insensitive to priming with flg22, a well-known bacterial PAMP which induces enhanced resistance in WT plants. The defective defense response in 3h1 upon priming was correlated with altered DNA methylation and reduced global H3K56ac levels. Our data place H1 as a molecular gatekeeper in governing dynamic changes in the chromatin landscape of defense genes during plant pathogen interaction.

Type-I/Type-II Transition of MoSe2/g-GaN van der Waals heterostructures mediated by biaxial strain and electric field for overall water splitting

Abstract: Nowadays, the fabrication of van der Waals heterostructures (vdWHs) from a variety of novel and existing two-dimensional materials has been regarded as an effective approach since it unravels excellent photocatalytic properties. Especially, transforming type-I to type-II vdWHs has gained significant attention due to efficient charge separation in photocatalytic, and photovoltaic devices. Here, we suggest two-dimensional MoSe2/GaN vdW heterostructures along with their mechanical, electronic, photocatalytic, and optical properties using hybrid density functional. The stability of vertically stacked MoSe2/GaN vdWHs is endorsed via binding energy, elastic constants, phonon dispersion, and ab-initio molecular dynamics simulation (AIMD). The HSE band structure and band alignment exhibit that MoSe2/GaN vdWH has a direct bandgap and suitable band edges for the hydrogen evolution reaction (HER) (ΔEc ≥ 0.36 eV) and oxygen evolution reaction (OER) (ΔEv ≥ 0.33 eV). The empirical and DFT schemes reveal that the MoSe2/GaN vdWHs have an intrinsic type-I band alignment with a direct bandgap and have adequately high kinetic over potentials to easily start the redox reaction. Furthermore, it’s also anticipated that type-I MoSe2/GaN vdWHs could be transformed to type-II vdWHs under mild strains and external electric fields, which would be favorable for effective charge separation and transportation. Notably, MoSe2/GaN vdWH shows a significantly high optical absorption of nearly 105 cm−1 in the visible and ultraviolet regions which could be more easily tuned with applied strain. Current work demonstrates that the design and modulation of MoSe2/GaN vdW heterostructures under strain and an electric field could open new directions for identifying promising photocatalysts in a wide solar spectrum.

Controlled Manufacture of Heterogeneous Catalysts for the Hydrogenation of CO₂ via Steam Pyrolysis of Different Metal–Organic Frameworks

Abstract: The use of metal–organic frameworks (MOFs) as precursors for the manufacture of heterogeneous catalysts has gained a great deal of attention over the last decade. By subjecting a given MOF to pyrolysis, electrochemical degradation, or other treatments under a controlled atmosphere, (supported) metal (oxide) nanoparticles with very narrow size distributions can be obtained, opening the door to the design of more efficient catalytic solids. Here, we demonstrate the benefits of steam during the controlled decomposition of two different MOF structures (Basolite F300(Fe) and In@ZIF-67(Co)) and the consequences of treatment under this mildly oxidizing atmosphere on the properties of the resulting catalysts for the direct hydrogenation of CO2 to hydrocarbons and methanol. In-depth characterization demonstrates that steam addition helps to control the phase composition both before and after catalysis; additionally, it results in the formation of smaller nanoparticles, thus leading to more efficient catalysts in comparison with conventional pyrolysis.

Epigenetics and Brain Plasticity: Back to Function

Abstract: Throughout our entire life, our brain is constantly shaped by the experience of both the outer and the inner environments. Sensory perceptions, as well as thoughts and feelings, are constantly processed and integrated in order to create a plastic representation of these environments and to efficiently adapt to perturbations; such a high demand of plasticity is met by the extraordinary capacity of our nervous system to quickly modify upon specific stimuli. Since a great number of neuronal plasticity processes rely on changes in gene induction/repression, a responsive, fine-tuned regulation of gene expression is of primary importance for a correct adaptation. Epigenetic regulation orchestrates the spatiotemporal regulation of gene expression in response to intracellular and extracellular stimuli, specifically through modifying chromatin accessibility to the transcriptional machinery, and is therefore likely to play a fundamental role in nervous system homeostasis and functioning. Despite being studied for more than forty years, our current understanding of the importance of epigenetics, particularly in highly complex fields such as neurophysiology and cognitive processes, is still very limited. This chapter aims to summarize our current knowledge on the role epigenetics plays in brain repair and how epigenome alterations may be involved in the pathophysiology of some common psychiatric disorders.

Hybrid distributed acoustic sensing and Kramers–Kronig communication system over a two-mode fiber

Abstract: We report on the co-propagation of distributed acoustic sensing (DAS) and Kramers–Kronig communication scheme over a two-mode fiber, achieving DAS with a signal-to-noise ratio larger than 2 dB and gross data rate of 2.04 Gbps.

Reply on RC3

Abstract: Abstract. Dark CO₂ fixation by bacteria is believed to be particularly important in oligotrophic ecosystems. However, only a few studies have characterized the role of bacterial dissolved inorganic carbon (DIC) fixation in global carbon dynamics. Therefore, this study quantified the primary production (PP), total bacteria dark CO₂ fixation (TB_DIC fixation), and heterotrophic bacterial production (HBP) in the warm and oligotrophic Red Sea using stable isotope labeling and cavity ring-down spectroscopy (¹³C-CRDS). Additionally, we assessed the contribution of bacterial DIC fixation (TB_DIC %) relative to the total DIC fixation (Total_DIC fixation). Our study demonstrated that TB_DIC fixation increased the Total_DIC fixation from 2.03 to 60.45 µg C L⁻¹ d⁻¹ within the photic zone, contributing 13.18 % to 71.68 % with an average value of 33.95 ± 0.02 % of the photic layer Total_DIC fixation. The highest TB_DIC fixation values were measured at the surface and deep (400 m) water with an average value of 5.23 ± 0.45 µg µg C L⁻¹ d⁻¹, and 4.95 ± 1.33 µg C L⁻¹ d⁻¹, respectively. These findings suggest that the non-photosynthetic processes such as anaplerotic DIC reactions and chemo-autotrophic CO₂ fixation extended to the entire oxygenated water column. On the other hand, the % of TB_DIC contribution to Total_DIC fixation increased as primary production decreased (R² = 0.45, p <0.0001), suggesting the relevance of increased dark DIC fixation when photosynthetic production was low or absent, as observed in other systems. Therefore, when estimating the total carbon dioxide production in the ocean, dark DIC fixation must also be accounted as a crucial component of the carbon dioxide flux in addition to photosynthesis.

Functional relationships reveal differences in the water cycle representation of global water models

Abstract: Global water models are widely used for policy-making and in scientific studies, but substantial inter-model differences highlight the need for additional evaluation. Here we evaluate global water models by assessing so-called functional relationships between system forcing and response variables. The more widely used comparisons between observed and simulated fluxes provide insight into model behavior for the representative area of an observation, and can therefore potentially improve the model for that area. Functional relationships, by contrast, aim to capture how system forcing and response variables co-vary across large scales, and thus offer the potential for model improvement over large areas. Using 30-year annual averages from 8 global water models, we quantify such functional relationships by calculating correlations between key forcing variables (precipitation, net radiation) and water fluxes (actual evapotranspiration, groundwater recharge, total runoff). We find strong disagreement for groundwater recharge, some disagreement for total runoff, and the best agreement for evapotranspiration. Observation- and theory-derived functional relationships show varying agreements with models, indicating where model representations and our process understanding are particularly uncertain. Overall, our results suggest that model improvement is most important for the representation of energy balance processes, recharge processes, and generally for model behavior in dry and cold regions. We argue that advancing our ability to simulate global hydrology requires a better perceptual understanding of the global water cycle. To evaluate if our models match that understanding, we should explore alternative evaluation strategies, such as the use of functional relationships.