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Recent Submissions

  • Side Chain Redistribution as a Strategy to Boost Organic Electrochemical Transistor Performance and Stability

    Moser, Maximilian; Hidalgo, Tania Cecilia; Surgailis, Jokubas; Gladisch, Johannes; Ghosh, Sarbani; Sheelamanthula, Rajendar; Thiburce, Quentin; Giovannitti, Alexander; Salleo, Alberto; Gasparini, Nicola; Wadsworth, Andrew; Zozoulenko, Igor; Berggren, Magnus; Stavrinidou, Eleni; Inal, Sahika; McCulloch, Iain (Advanced Materials, Wiley, 2020-08-05) [Article]
    A series of glycolated polythiophenes for use in organic electrochemical transistors (OECTs) is designed and synthesized, differing in the distribution of their ethylene glycol chains that are tethered to the conjugated backbone. While side chain redistribution does not have a significant impact on the optoelectronic properties of the polymers, this molecular engineering strategy strongly impacts the water uptake achieved in the polymers. By careful optimization of the water uptake in the polymer films, OECTs with unprecedented steady-state performances in terms of [μC*] and current retentions up to 98% over 700 electrochemical switching cycles are developed.
  • Sensitivity of Cloud Microphysics on the Simulation of a Monsoon Depression Over the Bay of Bengal

    Podeti, Srinivasa Rao; Ramakrishna, S. S. V. S.; Viswanadhapalli, Yesubabu; Dasari, Hari Prasad; Nellipudi, Nanaji Rao; Rao, B. Ravi Srinivasa (Pure and Applied Geophysics, Springer Science and Business Media LLC, 2020-08-04) [Article]
    In this study, we have examined the role of implicit and explicit representation of cloud microphysics on the simulation of a monsoon depression formed over the Bay of Bengal and the associated rainfall from 0000 UTC of 13 August to 0000 UTC of 17 August 2018 using the Weather Research and Forecast model. Five different WRF model simulations are performed by changing the Cloud Micro Physics (CMP) schemes: WSM6, Goddard, Thompson, Morrison, and Thompson Scheme with Aerosol aware options in both explicit and implicit cloud models. WRF simula15 tions are conducted by initializing the NCEP GFS analysis at 0000 UTC of 13 August 2018 and integrated up to 96-h. The boundary conditions are updated at 6-hourly intervals with the respective GFS forecasts. Our results of sensitivity simulations suggest that the Thompson Scheme with Aerosol aware scheme, followed by Goddard microphysics, captured the features of monsoon depres21 sion and associated rainfall. Microphysics schemes have an influence on the simulation of low level westerly jet, and upper level easterly jet. Implicit and explicit cloud microphysics options are able to reproduce the convection over the west-coast, but the implicit option failed in producing the prolonged convection over the east coast. The comparison of model rainfall with rain-gauge, and satellite merged rainfall estimates reveals that the large scale off-shore precipitation is better captured in CMP with the inclusion of explicit cumulus parameterization. The orographic rainfall over the wind-ward and lee-ward sides of the Eastern and Western Ghats is well predicted in the implicit CMP. The vertical distribution of the hydrometeors and rainfall analysis suggest that the Thompson Scheme with Aerosol aware scheme with the cloud-resolving explicit mode is suitable for simulating the monsoon depressions formed over the Bay of Bengal and the associated heavy rainfall over the east coast of India.
  • Increased Antibacterial and Antibiofilm Properties of Silver Nanoparticles Using Silver Fluoride as Precursor

    Bertoglio, Federico; De Vita, Lorenzo; D’Agostino, Agnese; Diaz Fernandez, Yuri; Falqui, Andrea; Casu, Alberto; Merli, Daniele; Milanese, Chiara; Rossi, Silvia; Taglietti, Angelo; Visai, Livia; Pallavicini, Piersandro (Molecules, MDPI AG, 2020-08-03) [Article]
    Silver nanoparticles were produced with AgF as the starting Ag(I) salt, with pectin as the reductant and protecting agent. While the obtained nanoparticles (pAgNP-F) have the same dimensional and physicochemical properties as those already described by us and obtained from AgNO3 and pectin (pAgNP-N), the silver nanoparticles from AgF display an increased antibacterial activity against E. coli PHL628 and Staphylococcus epidermidis RP62A (S. epidermidis RP62A), both as planktonic strains and as their biofilms with respect to pAgNP-N. In particular, a comparison of the antimicrobial and antibiofilm action of pAgNP-F has been carried out with pAgNP-N, pAgNP-N and added NaF, pure AgNO3, pure AgF, AgNO3 and added NaF and pure NaNO3 and NaF salts. By also measuring the concentration of the Ag+ cation released by pAgNP-F and pAgNP-N, we were able to unravel the separate contributions of each potential antibacterial agent, observing an evident synergy between p-AgNP and the F− anion: the F− anion increases the antibacterial power of the p-AgNP solutions even when F− is just 10 µM, a concentration at which F− alone (i.e., as its Na+ salt) is completely ineffective.
  • Comparative infection modeling and control of COVID-19 transmission patterns in China, South Korea, Italy and Iran

    He, Junyu; Chen, Guangwei; Jiang, Yutong; Jin, Runjie; Shortridge, Ashton; Agusti, Susana; He, Mingjun; Wu, Jiaping; Duarte, Carlos M.; Christakos, George (Science of The Total Environment, Elsevier BV, 2020-08-03) [Article]
    The COVID-19 has become a pandemic. The timing and nature of the COVID-19 pandemic response and control varied among the regions and from one country to the other, and their role in affecting the spread of the disease has been debated. The focus of this work is on the early phase of the disease when control measures can be most effective. We proposed a modified susceptible-exposed-infected-removed model (SEIR) model based on temporal moving windows to quantify COVID-19 transmission patterns and compare the temporal progress of disease spread in six representative regions worldwide: three Chinese regions (Zhejiang, Guangdong and Xinjiang) vs. three countries (South Korea, Italy and Iran). It was found that in the early phase of COVID-19 spread the disease follows a certain empirical law that is common in all regions considered. Simulations of the imposition of strong social distancing measures were used to evaluate the impact that these measures might have had on the duration and severity of COVID-19 outbreaks in the three countries. Measure-dependent transmission rates followed a modified normal distribution (empirical law) in the three Chinese regions. These rates responded quickly to the launch of the 1st-level Response to Major Public Health Emergency in each region, peaking after 1–2 days, reaching their inflection points after 10–19 days, and dropping to zero after 11–18 days since the 1st-level response was launched. By March 29th, the mortality rates were 0.08% (Zhejiang), 0.54% (Guangdong) and 3.95% (Xinjiang). Subsequent modeling simulations were based on the working assumption that similar infection transmission control measures were taken in South Korea as in Zhejiang on February 25th, in Italy as in Guangdong on February 25th, and in Iran as in Xinjiang on March 8th. The results showed that by June 15th the accumulated infection cases could have been reduced by 32.49% (South Korea), 98.16% (Italy) and 85.73% (Iran). The surface air temperature showed stronger association with transmission rate of COVID-19 than surface relative humidity. On the basis of these findings, disease control measures were shown to be particularly effective in flattening and shrinking the COVID-10 case curve, which could effectively reduce the severity of the disease and mitigate medical burden. The proposed empirical law and the SEIR-temporal moving window model can also be used to study infectious disease outbreaks worldwide.
  • Sequencing Effort Dictates Gene Discovery in Marine Microbial Metagenomes

    Duarte, Carlos M.; Ngugi, David; Alam, Intikhab; Pearman, John K.; Kamau, Allan; Eguíluz, V. M.; Gojobori, Takashi; Acinas, Silvia G.; Gasol, Josep M.; Bajic, Vladimir B.; Irigoien, Xabier (Environmental Microbiology, Wiley, 2020-08-03) [Article]
    Massive metagenomic sequencing combined with gene prediction methods were previously used to compile the gene catalogue of ocean and host-associated microbes. Global expeditions conducted over the past 15 years have sampled to ocean to build a catalogue of genes from pelagic microbes. Here we undertook a large sequencing effort of a perturbed Red Sea plankton community to uncover that the rate of gene discovery increases continuously with sequencing effort, with no indication that the retrieved 2.83 million non-redundant (complete) genes predicted from the experiment represented a nearly complete inventory of the genes present in the sampled community (i.e. no evidence of saturation). The underlying reason is the Pareto-like distribution of the abundance of genes in the plankton community, resulting in a very long tail of millions of genes present at remarkably low abundances, which can only be retrieved through massive sequencing. Microbial metagenomic projects retrieve variable number of unique genes per Tera base-pair (Tbp), with a median value of 14.7 million unique genes per Tbp sequenced across projects. The increase in the rate of gene discovery in microbial metagenomes with sequencing effort implies that there is ample room for new gene discovery in further ocean and holobiont sequencing studies This article is protected by copyright. All rights reserved.
  • Symbiodiniaceae diversity of Palythoa tuberculosa in the central and southern Red Sea influenced by environmental factors

    Wee, Hin Boo; Berumen, Michael L.; Ravasi, Timothy; Reimer, James Davis (Coral Reefs, Springer Science and Business Media LLC, 2020-08-03) [Article]
    Sea surface temperatures (SST) and chlorophyll a concentrations (Chl a) in the southern Red Sea have wide variations based on distance from the coast. To understand how these variations can affect the diversity of symbionts hosted by reef-associated organisms, we conducted a study in the central and southern Red Sea to examine the diversity of Symbiodiniaceae hosted by the zooxanthellate zoantharian Palythoa tuberculosa at different distances from the coast: offshore (FBO), midshelf (FBM) and inshore (FBI) of Farasan Banks, and inshore at Thuwal (TI). Genomic DNA was extracted from 198 specimens, followed by amplification of the ribosomal DNA internal transcribed spacer 2 (ITS-2) and noncoding region of the chloroplast plastid minicircle (psbAncr). Durusdinium and six lineages of Cladocopium (Pt-1-a, Pt-1-b, Pt-1-c, Pt-1-d, Pt-3-a, Pt-3-b) were identified based on sequences of the two marker regions. Changes in composition of Symbiodiniaceae lineages were observed from FBI (high SST, high Chl a) to FBO (low SST, low Chl a). Molecular variance analyses showed that distance from coast was the most likely predictor of differences in Cladocopium lineages. Multinomial logistic regression analysis showed a transition among different Cladocopium lineages as SST increased. One Cladocopium lineage, Pt-1-b, demonstrated higher prevalences at high SSTs and increased in prevalences at the same rate as thermotolerant Durusdinium. Additionally, Cladocopium lineage Pt-3-a had a high affinity to low Chl a concentrations. This study demonstrates that environmental variations in SSTs and Chl a concentrations are significant predictors for the diversity of dominant Symbiodiniaceae within individual host P. tuberculosa colonies. We theorize that flexibility with different lineages of Symbiodiniaceae allows generalist P. tuberculosa to live across a wide range of environments in the southern Red Sea.
  • On the biosynthesis and evolution of apocarotenoid plant growth regulators.

    Wang, Jian You; Lin, Pei-Yu; Al-Babili, Salim (Seminars in cell & developmental biology, Elsevier BV, 2020-08-01) [Article]
    Carotenoids are an important source of metabolites with regulatory function, which include the plant hormones abscisic acid (ABA) and strigolactones (SLs), and several recently identified growth regulators and signaling molecules. These carotenoid-derivatives originate from oxidative breakdown of double bonds in the carotenoid polyene, a common metabolic process that gives rise to diverse carbonyl cleavage-products known as apocarotenoids. Apocarotenoids exert biologically important functions in all taxa. In plants, they are a major regulator of plant growth, development and response to biotic and abiotic environmental stimuli, and mediate plant's communication with surrounding organisms. In this article, we provide a general overview on the biology of plant apocarotenoids, focusing on ABA, SLs, and recently identified apocarotenoid growth regulators. Following an introduction on carotenoids, we describe plant apocarotenoid biosynthesis, signal transduction, and evolution and summarize their biological functions. Moreover, we discuss the evolution of these intriguing metabolites, which has not been adequately addressed in the literature.
  • Healthy soils for healthy plants for healthy humans

    Hirt, Heribert (EMBO reports, EMBO, 2020-07-31) [Article]
    The microbiota of the human gut and the plant rhizome are similar in many ways and intricately connected with each other. A healthy plant therefore affects human microbiota and human health.
  • Room-Temperature Valley Polarization in Atomically Thin Semiconductors via Chalcogenide Alloying

    Liu, Sheng; Granados del Águila, Andrés; Liu, Xue; Zhu, Yihan; Han, Yu; Chaturvedi, Apoorva; Gong, Pu; Yu, Hongyi; Zhang, Hua; Yao, Wang; Xiong, Qihua (ACS Nano, American Chemical Society (ACS), 2020-07-31) [Article]
    Room-temperature manipulation and processing of information encoded in the electronic valley pseudospin and spin degrees of freedoms lie at the heart of the next technological quantum revolution. In atomically thin layers of transition-metal dichalcogenides (TMDs) with hexagonal lattices, valley-polarized excitations and valley quantum coherence can be generated by simply shining with adequately polarized light. In turn, the polarization states of light can induce topological Hall currents in the absence of an external magnetic field, which underlies the fundamental principle of opto-valleytronics devices. However, demonstration of optical generation of valley polarization at room temperature has remained challenging and not well understood. Here, we demonstrate control of strong valley polarization (valley quantum coherence) at room temperature of up to ∼50% (∼20%) by strategically designing Coulomb forces and spin−orbit interactions in atomically thin TMDs via chalcogenide alloying. We show that tailor making the carrier density and the relative order between optically active (bright) and forbidden (dark) states by key variations on the chalcogenide atom ratio allows full control of valley pseudospin dynamics. Our findings set a comprehensive approach for intrinsic and efficient manipulation of valley pseudospin and spin degree of freedom toward realistic opto-valleytronics devices.
  • An Integrated Photocatalytic and Photothermal Process for Solar-Driven Efficient Purification of Complex Contaminated Water

    Shi, Le; Shi, Yusuf; Zhang, Chenlin; Zhuo, Sifei; Wang, Wenbin; Li, Renyuan; Wang, Peng (Energy Technology, Wiley, 2020-07-31) [Article]
    With the water and energy crises becoming critical issues for an increasingly industrialized society, solar-driven water purification technologies are highly desired for both potable water production and wastewater treatment. Herein, the performance of an integrated photocatalytic and photothermal composite, TiO2/Au-carbon nanotube (TiO2/Au-CNT)-coated SiC ceramic plate, in complex contaminated water treatment driven by solar energy is investigated. The short-wavelength part of the solar spectrum is used for simultaneous photo-oxidation of rhodamine B (RhB) (oxidation efficiency of ≈98.5%) and photo-reduction of Cr(VI) (reduction efficiency of ≈90.6%) in an integrated solar still device. A Z-scheme charge transfer mechanism with CNTs as an electron mediator is proposed and discussed for TiO2/Au-CNT-coated SiC ceramic plate. Meanwhile, the design here allowed the long-wavelength part of the solar spectrum to be utilized for high-quality potable clean water production via solar distillation with a solar-to-water evaporation efficiency of ≈72%. Therefore, this integrated photocatalytic and photothermal system can be utilized for potable water production and wastewater treatment in the same device with high solar energy utilization efficiency.
  • Viral Metagenomic Content Reflects Seawater Ecological Quality in the Coastal Zone.

    Tsiola, Anastasia; Michoud, Gregoire; Fodelianakis, Stylianos; Karakassis, Ioannis; Kotoulas, Georgios; Pavlidou, Alexandra; Pavloudi, Christina; Pitta, Paraskevi; Simboura, Nomiki; Daffonchio, Daniele; Tsapakis, Manolis (Viruses, MDPI AG, 2020-07-30) [Article]
    Viruses interfere with their host's metabolism through the expression of auxiliary metabolic genes (AMGs) that, until now, are mostly studied under large physicochemical gradients. Here, we focus on coastal marine ecosystems and we sequence the viral metagenome (virome) of samples with discrete levels of human-driven disturbances. We aim to describe the relevance of viromics with respect to ecological quality status, defined by the classic seawater trophic index (TRIX). Neither viral (family level) nor bacterial (family level, based on 16S rRNA sequencing) community structure correlated with TRIX. AMGs involved in the Calvin and tricarboxylic acid cycles were found at stations with poor ecological quality, supporting viral lysis by modifying the host's energy supply. AMGs involved in "non-traditional" energy-production pathways (3HP, sulfur oxidation) were found irrespective of ecological quality, highlighting the importance of recognizing the prevalent metabolic paths and their intermediate byproducts. Various AMGs explained the variability between stations with poor vs. good ecological quality. Our study confirms the pivotal role of the virome content in ecosystem functioning, acting as a "pool" of available functions that may be transferred to the hosts. Further, it suggests that AMGs could be used as an ultra-sensitive metric of energy-production pathways with relevance in the vulnerable coastal zone and its ecological quality.
  • Downscaling Multispectral Satellite Images Without Colocated High-Resolution Data: A Stochastic Approach Based on Training Images

    Oriani, Fabio; McCabe, Matthew; Mariethoz, Gregoire (IEEE Transactions on Geoscience and Remote Sensing, Institute of Electrical and Electronics Engineers (IEEE), 2020-07-30) [Article]
    Very high-resolution satellite imagery from the latest generation commercial platforms provides an unprecedented capacity for imaging the Earth with very high spatial detail. However, these data are generally expensive, particularly if large areas or temporal sequences are required. In recent years, lower quality imagery has been enabled through the launch of constellations of small satellites with short revisit time. In this article, we apply for the first time a statistical approach to downscale and bias-correct these multispectral satellite data using the information contained in a limited training set of very highresolution images. The technique, based on the direct sampling algorithm, aims at extending the coverage of high-resolution images by sampling data from a training data set, where similar lower resolution data patterns are found. Unlike the majority of the current downscaling techniques, the approach does not require colocated fine-resolution data, but it is based on the use of training images similar to the target zone. A novel specific setup is proposed, which is adaptive to different types of landscapes with no additional user effort. The results show that the proposed technique can generate more realistic images than the traditional approaches based on the parametric bias correction and bicubic interpolation. In particular, properties such as the intensity histogram, spatial correlation, and connectivity are accurately preserved. The proposed approach can be used to extend the footprint of the high-resolution images to generate new time frames or to downscale the remote sensing imagery based on a distant but structurally similar training image.
  • Monitoring the insertion of Pt into Cu2−xSe nanocrystals: a combined structural and chemical approach for the analysis of new ternary phases

    Casu, Alberto; Dalmases, Mariona; Lin, Mengxi; Wang, Yan; Homs, Narcís; Ramírez de la Piscina, Pilar; Llorca, Jordi; Figuerola, Albert; Falqui, Andrea (Nanoscale, Royal Society of Chemistry (RSC), 2020-07-30) [Article]
    The work explores the reactions between Cu$_{2−x}$Se premade nanoparticles and a Pt(ii) precursor, and confirms the formation of ternary CuPtSe phases with flexible stoichiometry and photocatalytic activity towards the hydrogen evolution reaction.
  • Functional annotation of human long noncoding RNAs via molecular phenotyping.

    Ramilowski, Jordan A; Yip, Chi Wai; Agrawal, Saumya; Chang, Jen-Chien; Ciani, Yari; Kulakovskiy, Ivan V; Mendez, Mickaël; Ooi, Jasmine Li Ching; Ouyang, John F; Parkinson, Nick; Petri, Andreas; Roos, Leonie; Severin, Jessica; Yasuzawa, Kayoko; Abugessaisa, Imad; Akalin, Altuna; Antonov, Ivan V; Arner, Erik; Bonetti, Alessandro; Bono, Hidemasa; Borsari, Beatrice; Brombacher, Frank; Cameron, Chris J F; Cannistraci, Carlo Vittorio; Cardenas, Ryan; Cardon, Melissa; Chang, Howard; Dostie, Josée; Ducoli, Luca; Favorov, Alexander; Fort, Alexandre; Garrido, Diego; Gil, Noa; Gimenez, Juliette; Guler, Reto; Handoko, Lusy; Harshbarger, Jayson; Hasegawa, Akira; Hasegawa, Yuki; Hashimoto, Kosuke; Hayatsu, Norihito; Heutink, Peter; Hirose, Tetsuro; Imada, Eddie L; Itoh, Masayoshi; Kaczkowski, Bogumil; Kanhere, Aditi; Kawabata, Emily; Kawaji, Hideya; Kawashima, Tsugumi; Kelly, S Thomas; Kojima, Miki; Kondo, Naoto; Koseki, Haruhiko; Kouno, Tsukasa; Kratz, Anton; Kurowska-Stolarska, Mariola; Kwon, Andrew Tae Jun; Leek, Jeffrey; Lennartsson, Andreas; Lizio, Marina; López-Redondo, Fernando; Luginbühl, Joachim; Maeda, Shiori; Makeev, Vsevolod J; Marchionni, Luigi; Medvedeva, Yulia A; Minoda, Aki; Müller, Ferenc; Muñoz-Aguirre, Manuel; Murata, Mitsuyoshi; Nishiyori, Hiromi; Nitta, Kazuhiro R; Noguchi, Shuhei; Noro, Yukihiko; Nurtdinov, Ramil; Okazaki, Yasushi; Orlando, Valerio; Paquette, Denis; Parr, Callum J C; Rackham, Owen J L; Rizzu, Patrizia; Sánchez Martinez, Diego Fernando; Sandelin, Albin; Sanjana, Pillay; Semple, Colin A M; Shibayama, Youtaro; Sivaraman, Divya M; Suzuki, Takahiro; Szumowski, Suzannah C; Tagami, Michihira; Taylor, Martin S; Terao, Chikashi; Thodberg, Malte; Thongjuea, Supat; Tripathi, Vidisha; Ulitsky, Igor; Verardo, Roberto; Vorontsov, Ilya E; Yamamoto, Chinatsu; Young, Robert S; Baillie, J Kenneth; Forrest, Alistair R R; Guigó, Roderic; Hoffman, Michael M; Hon, Chung Chau; Kasukawa, Takeya; Kauppinen, Sakari; Kere, Juha; Lenhard, Boris; Schneider, Claudio; Suzuki, Harukazu; Yagi, Ken; de Hoon, Michiel J L; Shin, Jay W; Carninci, Piero (Genome research, Cold Spring Harbor Laboratory, 2020-07-29) [Article]
    Long noncoding RNAs (lncRNAs) constitute the majority of transcripts in the mammalian genomes, and yet, their functions remain largely unknown. As part of the FANTOM6 project, we systematically knocked down the expression of 285 lncRNAs in human dermal fibroblasts and quantified cellular growth, morphological changes, and transcriptomic responses using Capped Analysis of Gene Expression (CAGE). Antisense oligonucleotides targeting the same lncRNAs exhibited global concordance, and the molecular phenotype, measured by CAGE, recapitulated the observed cellular phenotypes while providing additional insights on the affected genes and pathways. Here, we disseminate the largest-to-date lncRNA knockdown data set with molecular phenotyping (over 1000 CAGE deep-sequencing libraries) for further exploration and highlight functional roles for ZNF213-AS1 and lnc-KHDC3L-2.
  • Recruitment of coral reef fishes along a cross-shelf gradient in the Red Sea peaks outside the hottest season

    Robitzch Sierra, Vanessa S. N.; Berumen, Michael L. (Coral Reefs, Springer Science and Business Media LLC, 2020-07-29) [Article]
    Knowledge on the early life history, ecology, and biology of marine species is crucial for future projections of the resilience of coral reef ecosystems and for adequate management strategies. A fundamental component of population dynamics is the recruitment of new individuals, and in some marine populations, this may be a limiting factor. Recruitment peaks of coral reef fishes commonly occur during the warmer months of the year in many subtropical and temperate locations worldwide. In the Red Sea, very little is known about the influence of temperature on reproductive patterns of coral reef fishes and studies on recruitment are missing. The Red Sea is one of the hottest and most isolated tropical seas in the world. We hypothesized that sea surface temperatures (SSTs) during the Red Sea’s hottest season may exceed the optimum for successful recruitment of some coral reef fishes, which therefore has to occur during other, cooler seasons, unlike recruitment among coral reef ecosystems around the world. We identified taxa among fish recruits by matching mitochondrial DNA sequences (using COI, commonly known as “barcoding”) and assessed potential biological and environmental drivers of recruitment. We studied three reefs located along a cross-shelf gradient for 12 consecutive months in the central Red Sea to capture seasonal changes in biotic and abiotic parameters along this gradient. Our results indicated that recruitment peaks did not occur during the hottest SSTs for most taxa, especially at the hottest inshore and mid-shelf reefs, and identified fish recruitment to be mainly and strongly correlated with the biomass of planktonic invertebrates. Moreover, temporal patterns of fish recruitment differed within and among taxonomic families among the reefs.
  • Tuning the Surface Structure of Polyamide Membranes Using Porous Carbon Nitride Nanoparticles for High-Performance Seawater Desalination

    Zhou, Zongyao; Li, Xiang; Shinde, Digambar; Sheng, Guan; Lu, Dongwei; Li, Peipei; Lai, Zhiping (Membranes, MDPI AG, 2020-07-24) [Article]
    Enhancing the water flux while maintaining the high salt rejection of existing reverse osmosis membranes remains a considerable challenge. Herein, we report the use of a porous carbon nitride (C3N4) nanoparticle to potentially improve both the water flux and salt rejection of the state-of-the-art polyamide (PA) thin film composite (TFC) membranes. The organic–organic covalent bonds endowed C3N4 with great compatibility with the PA layer, which positively influenced the customization of interfacial polymerization (IP). Benefitting from the positive effects of C3N4, a more hydrophilic, more crumpled thin film nanocomposite (TFN) membrane with a larger surface area, and an increased cross-linking degree of PA layer was achieved. Moreover, the uniform porous structure of the C3N4 embedded in the ”ridge” sections of the PA layer potentially provided additional water channels. All these factors combined provided unprecedented performance for seawater desalination among all the PA-TFC membranes reported thus far. The water permeance of the optimized TFN membrane is 2.1-folds higher than that of the pristine PA-TFC membrane, while the NaCl rejection increased to 99.5% from 98.0%. Our method provided a promising way to improve the performance of the state-of-art PA-TFC membranes in seawater desalination.
  • Dissecting new genetic components of salinity tolerance in two-row spring barley at the vegetative and reproductive stages

    saade, stephanie; Brien, Chris; Pailles, Yveline; Berger, Bettina; Shahid, Mohammad; Russell, Joanne; Waugh, Robbie; Negrão, Sónia; Tester, Mark A. (PLOS ONE, Public Library of Science (PLoS), 2020-07-23) [Article]
    Soil salinity imposes an agricultural and economic burden that may be alleviated by identifying the components of salinity tolerance in barley, a major crop and the most salt tolerant cereal. To improve our understanding of these components, we evaluated a diversity panel of 377 two-row spring barley cultivars during both the vegetative, in a controlled environment, and the reproductive stages, in the field. In the controlled environment, a high-throughput phenotyping platform was used to assess the growth-related traits under both control and saline conditions. In the field, the agronomic traits were measured from plots irrigated with either fresh or saline water. Association mapping for the different components of salinity tolerance enabled us to detect previously known associations, such as HvHKT1;5. Using an "interaction model", which took into account the interaction between treatment (control and salt) and genetic markers, we identified several loci associated with yield components related to salinity tolerance. We also observed that the two developmental stages did not share genetic regions associated with the components of salinity tolerance, suggesting that different mechanisms play distinct roles throughout the barley life cycle. Our association analysis revealed that genetically defined regions containing known flowering genes (Vrn-H3, Vrn-H1, and HvNAM-1) were responsive to salt stress. We identified a salt-responsive locus (7H, 128.35 cM) that was associated with grain number per ear, and suggest a gene encoding a vacuolar H+-translocating pyrophosphatase, HVP1, as a candidate. We also found a new QTL on chromosome 3H (139.22 cM), which was significant for ear number per plant, and a locus on chromosome 2H (141.87 cM), previously identified using a nested association mapping population, which associated with a yield component and interacted with salinity stress. Our study is the first to evaluate a barley diversity panel for salinity stress under both controlled and field conditions, allowing us to identify contributions from new components of salinity tolerance which could be used for marker-assisted selection when breeding for marginal and saline regions.
  • Carbon quantum dots enabled tuning of the microphase structures of poly (ether-b-amide) membrane for CO2 separation

    Shi, Fei; Tian, Qianqian; Wang, Jingtao; Wang, Qi; Shi, Feng; Li, Yifan; Nunes, Suzana Pereira (Industrial & Engineering Chemistry Research, American Chemical Society (ACS), 2020-07-23) [Article]
    In this study, molecular-level of mixed matrix membranes are prepared by incorporating two types of carbon quantum dots (QDs), polymer-like QDs (PQD) and graphene oxide QDs (GQD) into Pebax, a poly (ether-b-amide) copolymer. PQD is shown to destroy part of the intrinsic crystalline structure of Pebax as typical fillers do. By comparison, GQD has fewer functional groups and causes an interesting enhancement of the microphase separation of Pebax. The polyether domains become more segregated and more available for the selective CO2 permeation. As a result, the gas separation performance of the membranes is evidently enhanced. GQD outperforms PQD as filler and the encouraging enhancement occurs at lower loading. The membrane with 0.05 wt% GQD loading shows the optimal gas separation property while it is 1 wt% for PQD-doped membranes. A possible mechanism is tentatively proposed based on the findings of this study.
  • NEXARTM-coated hollow fibers for air dehumidification

    Upadhyaya, Lakshmeesha; Gebreyohannes, Abaynesh Yihdego; Akhtar, Faheem; Falca, Gheorghe; Musteata, Valentina-Elena; Mahalingam, Dinesh K.; Almansoury, Rneem; Ng, Kim Choon; Nunes, Suzana Pereira (Journal of Membrane Science, Elsevier BV, 2020-07-22) [Article]
    Air conditioning is one of the essential requirements for households as well as work stations. Dehumidification in air conditioning is the highest energy-consuming component, where membranes could play a crucial role. In this work, we propose the coating of NEXARTM, a commercial pentablock copolymer in tetrahydrofuran on polyetherimide hollow fiber support for separation of water vapor from humidified air. The block copolymer in tetrahydrofuran forms a lamellar/parallel cylindrical structure separated by equidistance during the morphological transformation process giving its unique characteristics with higher water vapor transfer efficiency. Both vacuum and sweep gas modes of membrane dehumidification strategies are investigated along with the detailed study of the morphological transformation process under a controlled environment, which is supported by comprehensive scanning electron microscopic and atomic force microscopic imaging. The membrane has shown water vapor permeance up to 9089 GPU with water vapor to nitrogen selectivity up to 3870. The membrane can reduce the relative humidity from 80% to 41% proving one of the competitive materials for membrane dehumidification.
  • Ethylene Glycol-Based Side Chain Length Engineering in Polythiophenes and its Impact on Organic Electrochemical Transistor Performance

    Moser, Maximilian; Savagian, Lisa R.; Savva, Achilleas; Matta, Micaela; Ponder, James F.; Hidalgo, Tania Cecilia; ohayon, David; Hallani, Rawad; Reisjalali, Maryam; Troisi, Alessandro; Wadsworth, Andrew; Reynolds, John R.; Inal, Sahika; McCulloch, Iain (Chemistry of Materials, American Chemical Society (ACS), 2020-07-22) [Article]
    Replacing the alkyl side chains on conventional semiconducting polymers with ethylene glycol (EG)-based chains is a successful strategy in the molecular design of mixed conduction materials for bioelectronic devices, including organic electrochemical transistors (OECTs). Such polymers have demonstrated the capability to conduct both ionic and electronic charges and can offer superior performance compared to the most commonly used active material, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). While many research efforts have been dedicated to optimizing OECT performance through the engineering of the semiconducting polymers’ conjugated backbones, variation of the EG chain length has been investigated considerably less. In this work, a series of glycolated polythiophenes with pendant EG chains spanning two to six EG repeat units was synthesized and the electrochemical and structural characteristics of the resulting films were characterized by experimental means and molecular dynamics simulations. OECTs were fabricated and tested, and their performance showed a strong correlation to the the EG side chain length, thereby elucidating important structure−property guidelines for the molecular design of future channel materials. Specifically, a careful balance in the EG length must be struck during the design of EG-functionalized conjugated polymers for OECTs. While minimizing the EG side chain length appears to boost both the capacitive and charge carrier transport properties of the polymers, the chosen EG side chain length must be kept sufficiently long to induce solubility for processing, and allow for the necessary ion interactions with the conjugated polymer backbone.

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