Now showing items 1-20 of 22396

    • High-Level FPGA Accelerator Design for Structured-Mesh-Based Explicit Numerical Solvers

      Kamalakkannan, Kamalavasan; Mudalige, Gihan R.; Reguly, Istvan Z.; Fahmy, Suhaib A. (IEEE, 2021-05-17) [Conference Paper]
      This paper presents a workflow for synthesizing near-optimal FPGA implementations of structured-mesh based stencil applications for explicit solvers. It leverages key characteristics of the application class and its computation-communication pattern and the architectural capabilities of the FPGA to accelerate solvers for high-performance computing applications. Key new features of the workflow are (1) the unification of standard state-of-the-art techniques with a number of highgain optimizations such as batching and spatial blocking/tiling, motivated by increasing throughput for real-world workloads and (2) the development and use of a predictive analytical model to explore the design space, and obtain resource and performance estimates. Three representative applications are implemented using the design workflow on a Xilinx Alveo U280 FPGA, demonstrating near-optimal performance and over 85% predictive model accuracy. These are compared with equivalent highly-optimized implementations of the same applications on modern HPC-grade GPUs (Nvidia V100), analyzing time to solution, bandwidth, and energy consumption. Performance results indicate comparable runtimes with the V100 GPU, with over 2× energy savings for the largest non-trivial application on the FPGA. Our investigation shows the challenges of achieving high performance on current generation FPGAs compared to traditional architectures. We discuss determinants for a given stencil code to be amenable to FPGA implementation, providing insights into the feasibility and profitability of a design and its resulting performance.
    • Runtime Abstraction for Autonomous Adaptive Systems on Reconfigurable Hardware

      Bucknall, Alex R.; Fahmy, Suhaib A. (IEEE, 2021-02-01) [Conference Paper]
      Autonomous systems increasingly rely on on-board computation to avoid the latency overheads of offloading to more powerful remote computing. This requires the integration of hardware accelerators to handle the complex computations demanded by date-intensive sensors. FPGAs offer hardware acceleration with ample flexibility and interfacing capabilities when paired with general purpose processors, with the ability to reconfigure at runtime using partial reconfiguration. Managing dynamic hardware is complex and has been left to designers to address in an ad-hoc manner without first-class integration in autonomous software frameworks. This paper presents an abstracted runtime for managing adaptation of FPGA accelerators, including partial reconfiguration and parametric changes, that presents as a typical interface used in autonomous software systems. We present a demonstration using the Robot Operating System (ROS), showing negligible latency overhead as a result of the abstraction.
    • Symmetry-dependent field-free switching of perpendicular magnetization

      Liu, Liang; Zhou, Chenghang; Shu, Xinyu; Li, Changjian; Zhao, Tieyang; Lin, Weinan; Deng, Jinyu; Xie, Qidong; Chen, Shaohai; Zhou, Jing; Guo, Rui; Wang, Han; Yu, Jihang; Shi, Shu; Yang, Ping; Pennycook, S. J.; Manchon, Aurelien; Chen, Jingsheng (Nature Nanotechnology, Springer Science and Business Media LLC, 2021-01-18) [Article]
      Modern magnetic-memory technology requires all-electric control of perpendicular magnetization with low energy consumption. While spin–orbit torque (SOT) in heavy metal/ferromagnet (HM/FM) heterostructures1,2,3,4,5 holds promise for applications in magnetic random access memory, until today, it has been limited to the in-plane direction. Such in-plane torque can switch perpendicular magnetization only deterministically with the help of additional symmetry breaking, for example, through the application of an external magnetic field2,4, an interlayer/exchange coupling6,7,8,9 or an asymmetric design10,11,12,13,14. Instead, an out-of-plane SOT15 could directly switch perpendicular magnetization. Here we observe an out-of-plane SOT in an HM/FM bilayer of L11-ordered CuPt/CoPt and demonstrate field-free switching of the perpendicular magnetization of the CoPt layer. The low-symmetry point group (3m1) at the CuPt/CoPt interface gives rise to this spin torque, hereinafter referred to as 3m torque, which strongly depends on the relative orientation of the current flow and the crystal symmetry. We observe a three-fold angular dependence in both the field-free switching and the current-induced out-of-plane effective field. Because of the intrinsic nature of the 3m torque, the field-free switching in CuPt/CoPt shows good endurance in cycling experiments. Experiments involving a wide variety of SOT bilayers with low-symmetry point groups16,17 at the interface may reveal further unconventional spin torques in the future.
    • Protein Phosphatase 1 regulates atypical chromosome segregation and cell polarity during mitotic and meiotic division in Plasmodium sexual stages

      Zeeshan, Mohammad; Pandey, Rajan; Subudhi, Amit; Ferguson, David J P; Kaur, Gursimran; Rashpa, Ravish; Nugmanova, Raushan; Brady, Declan; Bottrill, Andrew R.; Vaughan, Sue; Brochet, Mathieu; Bollen, Mathieu; Pain, Arnab; Holder, Anthony A.; Guttery, David; Tewari, Rita (Cold Spring Harbor Laboratory, 2021-01-17) [Preprint]
      AbstractPP1 is a conserved eukaryotic serine/threonine phosphatase that regulates many aspects of mitosis and meiosis, often working in concert with other phosphatases, such as CDC14 and CDC25. The proliferative stages of the parasite life cycle include sexual development within the mosquito vector, with male gamete formation characterized by an atypical rapid mitosis, consisting of three rounds of DNA synthesis, successive spindle formation with clustered kinetochores, and a meiotic stage during zygote to ookinete development following fertilization. It is unclear how PP1 is involved in these unusual processes. Using real-time live-cell and ultrastructural imaging, conditional gene knockdown, RNA-seq and proteomic approaches, we show that Plasmodium PP1 is involved in both chromosome segregation during mitotic exit, and establishment of cell polarity during zygote development in the mosquito midgut, suggesting that small molecule inhibitors of PP1 should be explored for blocking parasite transmission.
    • Characterization of microbiologically influenced corrosion by comprehensive metagenomic analysis of an inland oil field.

      Nasser, Badoor Ali Hassan; Saito, Yoshimoto; Alarawi, Mohammed; Humam, Abdulmohsen A; Mineta, Katsuhiko; Gojobori, Takashi (Gene, Elsevier BV, 2021-01-15) [Article]
      Corrosion in pipelines and reservoir tanks in oil plants is a serious problem in the global energy industry because it causes substantial economic losses associated with frequent part replacement and can lead to potential damage to entire crude oil fields. Previous studies revealed that corrosion is mainly caused by microbial activities in a process currently termed microbiologically influenced corrosion (MIC) or biocorrosion. Identifying the bacteria responsible for biocorrosion is crucial for its suppression. In this study, we analyzed the microbial communities present at corrosion sites in oil plant pipelines using comparative metagenomic analysis along with bioinformatics and statistics. We analyzed the microbial communities in pipelines in an oil field in which groundwater is used as injection water. We collected samples from four different facilities in the oil field. Metagenomic analysis revealed that the microbial community structures greatly differed even among samples from the same facility. Treatments such as biocide administration and demineralization at each location in the pipeline may have independently affected the microbial community structure. The results indicated that microbial inspection throughout the pipeline network is essential to prevent biocorrosion at industrial plants. By identifying the bacterial species responsible for biocorrosion, this study provides bacterial indicators to detect and classify biocorrosion. Furthermore, these species may serve as biomarkers to detect biocorrosion at an early stage. Then, appropriate management such as treatment with suitable biocides can be performed immediately and appropriately. Thus, our study will serve as a platform for obtaining microbial information related to biocorrosion to enable the development of a practical approach to prevent its occurrence.
    • Characterization of microbiologically influenced corrosion by comprehensive metagenomic analysis of an inland oil field.

      Nasser, Badoor Ali Hassan; Saito, Yoshimoto; Alarawi, Mohammed; Humam, Abdulmohsen A; Mineta, Katsuhiko; Gojobori, Takashi (Gene, Elsevier BV, 2021-01-15) [Article]
      Corrosion in pipelines and reservoir tanks in oil plants is a serious problem in the global energy industry because it causes substantial economic losses associated with frequent part replacement and can lead to potential damage to entire crude oil fields. Previous studies revealed that corrosion is mainly caused by microbial activities in a process currently termed microbiologically influenced corrosion (MIC) or biocorrosion. Identifying the bacteria responsible for biocorrosion is crucial for its suppression. In this study, we analyzed the microbial communities present at corrosion sites in oil plant pipelines using comparative metagenomic analysis along with bioinformatics and statistics. We analyzed the microbial communities in pipelines in an oil field in which groundwater is used as injection water. We collected samples from four different facilities in the oil field. Metagenomic analysis revealed that the microbial community structures greatly differed even among samples from the same facility. Treatments such as biocide administration and demineralization at each location in the pipeline may have independently affected the microbial community structure. The results indicated that microbial inspection throughout the pipeline network is essential to prevent biocorrosion at industrial plants. By identifying the bacterial species responsible for biocorrosion, this study provides bacterial indicators to detect and classify biocorrosion. Furthermore, these species may serve as biomarkers to detect biocorrosion at an early stage. Then, appropriate management such as treatment with suitable biocides can be performed immediately and appropriately. Thus, our study will serve as a platform for obtaining microbial information related to biocorrosion to enable the development of a practical approach to prevent its occurrence.
    • A first-principles approach for treating wastewaters

      Santana, Adriano; Farinha, Andreia S. F.; Zarzar Torano, Aniela; Ibrahim, Mahmoud; Mishra, Himanshu (International Journal of Quantum Chemistry, Wiley, 2021-01-15) [Article]
      Numerous materials are employed for the removal of contaminants from wastewaters. However, the regeneration/reuse of these materials is still seldom practiced. Quantitative insights into intermolecular forces between the contaminants and the functional surfaces might aid the rational design of reusable materials. Here, we compare the efficacies of aliphatic (C8H18), aromatic (C6H6), and aromatic perfluorinated (C6F6) moieties at removing methylene blue (MB+) as a surrogate cationic dye from water. We employed density functional theory with an implicit polarizable continuum model for water to accurately determine the contributions of the solvent's electrostatics in the adsorption process. Our calculations pinpointed the relative contributions of ππ stacking, van der Waals complexation, hydrogen bonding, and cationπ interactions, predicting that MB+ would bind the strongest with C6F6 due to hydrogen bonding and the weakest with C8H18. Complementary laboratory experiments revealed that, despite the similar hydrophobicity of silica beads functionalized with SiC8H17, SiC6H5, and SiC6F5 groups, as characterized by their water contact angles, the relative uptake of aqueous MB+ varied as SiC6F5 (95%) > SiC6H5 (35%) > SiC8H17 (3%). This first principles-led experimental approach can be easily extended to other classes of dyes, thereby advancing the rational design of adsorbents.
    • A zero liquid discharge system integrating multi-effect distillation and evaporative crystallization for desalination brine treatment

      Chen, Qian; Burhan, Muhammad; Shahzad, Muhammad Wakil; Ybyraiymkul, Doskhan; Akhtar, Faheem; Li, Yong; Ng, Kim Choon (Desalination, Elsevier BV, 2021-01-13) [Article]
      With growing global desalination capacity, brine from desalination plants has become an environmental threat to the ecosystems. One sustainable method for brine treatment is to develop zero liquid discharge systems that completely convert seawater into freshwater and salts. This paper presents a zero liquid discharge system, which consists of multi-effect distillation and evaporative crystallization, to treat desalination brine with a salinity of 70 g/kg. A thermodynamic analysis is firstly conducted for the proposed system. The specific heat consumption, specific heat transfer area, and Second-law efficiency are found to be 600–1100 kJ/kg, 110–340 m2/(kg/s), and 10–17%, respectively. The heat consumption can be effectively reduced by increasing the number of MED stages, while the specific heat transfer area decreases significantly with higher heat source temperatures. Based on the thermodynamic performance, a techno-economic analysis is conducted for the proposed system, and the specific cost is calculated to be $4.17/m3. Cost reduction can be achieved via employing cost-effective heat sources, reducing heat consumption, and scaling up the system. By selling the freshwater and salt crystals, the system will be more competitive than other existing brine treatment methods.
    • Reactive Oxygen Species: Beyond Their Reactive Behavior.

      Tauffenberger, Arnaud; Magistretti, Pierre J. (Neurochemical research, Springer Science and Business Media LLC, 2021-01-13) [Article]
      Cellular homeostasis plays a critical role in how an organism will develop and age. Disruption of this fragile equilibrium is often associated with health degradation and ultimately, death. Reactive oxygen species (ROS) have been closely associated with health decline and neurological disorders, such as Alzheimer's disease or Parkinson's disease. ROS were first identified as by-products of the cellular activity, mainly mitochondrial respiration, and their high reactivity is linked to a disruption of macromolecules such as proteins, lipids and DNA. More recent research suggests more complex function of ROS, reaching far beyond the cellular dysfunction. ROS are active actors in most of the signaling cascades involved in cell development, proliferation and survival, constituting important second messengers. In the brain, their impact on neurons and astrocytes has been associated with synaptic plasticity and neuron survival. This review provides an overview of ROS function in cell signaling in the context of aging and degeneration in the brain and guarding the fragile balance between health and disease.
    • Change-point detection using spectral PCA for multivariate time series

      Jiao, Shuhao; Shen, Tong; Yu, Zhaoxia; Ombao, Hernando (arXiv, 2021-01-12) [Preprint]
      We propose a two-stage approach Spec PC-CP to identify change points in multivariate time series. In the first stage, we obtain a low-dimensional summary of the high-dimensional time series by Spectral Principal Component Analysis (Spec-PCA). In the second stage, we apply cumulative sum-type test on the Spectral PCA component using a binary segmentation algorithm. Compared with existing approaches, the proposed method is able to capture the lead-lag relationship in time series. Our simulations demonstrate that the Spec PC-CP method performs significantly better than competing methods for detecting change points in high-dimensional time series. The results on epileptic seizure EEG data and stock data also indicate that our new method can efficiently {detect} change points corresponding to the onset of the underlying events.
    • Impacts of hypoxic events surpass those of future ocean warming and acidification

      Sampaio, Eduardo; Santos, Catarina; Rosa, Inês C.; Ferreira, Verónica; Pörtner, Hans-Otto; Duarte, Carlos M.; Levin, Lisa A.; Rosa, Rui (Nature Ecology & Evolution, Springer Science and Business Media LLC, 2021-01-11) [Article]
      Over the past decades, three major challenges to marine life have emerged as a consequence of anthropogenic emissions: ocean warming, acidification and oxygen loss. While most experimental research has targeted the first two stressors, the last remains comparatively neglected. Here, we implemented sequential hierarchical mixed-model meta-analyses (721 control–treatment comparisons) to compare the impacts of oxygen conditions associated with the current and continuously intensifying hypoxic events (1–3.5 O2 mg l−1) with those experimentally yielded by ocean warming (+4 °C) and acidification (−0.4 units) conditions on the basis of IPCC projections (RCP 8.5) for 2100. In contrast to warming and acidification, hypoxic events elicited consistent negative effects relative to control biological performance—survival (–33%), abundance (–65%), development (–51%), metabolism (–33%), growth (–24%) and reproduction (–39%)—across the taxonomic groups (mollusks, crustaceans and fish), ontogenetic stages and climate regions studied. Our findings call for a refocus of global change experimental studies, integrating oxygen concentration drivers as a key factor of ocean change. Given potential combined effects, multistressor designs including gradual and extreme changes are further warranted to fully disclose the future impacts of ocean oxygen loss, warming and acidification.
    • The skeletome of the red coral Corallium rubrum indicates an independent evolution of biomineralization process in octocorals

      Le Roy, Nathalie; Ganot, Philippe; Aranda, Manuel; Allemand, Denis; Tambutté, Sylvie (BMC Ecology and Evolution, Springer Science and Business Media LLC, 2021-01-11) [Article]
      Abstract Background The process of calcium carbonate biomineralization has arisen multiple times during metazoan evolution. In the phylum Cnidaria, biomineralization has mostly been studied in the subclass Hexacorallia (i.e. stony corals) in comparison to the subclass Octocorallia (i.e. red corals); the two diverged approximately 600 million years ago. The precious Mediterranean red coral, Corallium rubrum, is an octocorallian species, which produces two distinct high-magnesium calcite biominerals, the axial skeleton and the sclerites. In order to gain insight into the red coral biomineralization process and cnidarian biomineralization evolution, we studied the protein repertoire forming the organic matrix (OM) of its two biominerals. Results We combined High-Resolution Mass Spectrometry and transcriptome analysis to study the OM composition of the axial skeleton and the sclerites. We identified a total of 102 OM proteins, 52 are found in the two red coral biominerals with scleritin being the most abundant protein in each fraction. Contrary to reef building corals, the red coral organic matrix possesses a large number of collagen-like proteins. Agrin-like glycoproteins and proteins with sugar-binding domains are also predominant. Twenty-seven and 23 proteins were uniquely assigned to the axial skeleton and the sclerites, respectively. The inferred regulatory function of these OM proteins suggests that the difference between the two biominerals is due to the modeling of the matrix network, rather than the presence of specific structural components. At least one OM component could have been horizontally transferred from prokaryotes early during Octocorallia evolution. Conclusion Our results suggest that calcification of the red coral axial skeleton likely represents a secondary calcification of an ancestral gorgonian horny axis. In addition, the comparison with stony coral skeletomes highlighted the low proportion of similar proteins between the biomineral OMs of hexacorallian and octocorallian corals, suggesting an independent acquisition of calcification in anthozoans.
    • MAAS: Multi-modal Assignation for Active Speaker Detection

      León-Alcázar, Juan; Heilbron, Fabian Caba; Thabet, Ali Kassem; Ghanem, Bernard (arXiv, 2021-01-11) [Preprint]
      Active speaker detection requires a solid integration of multi-modal cues. While individual modalities can approximate a solution, accurate predictions can only be achieved by explicitly fusing the audio and visual features and modeling their temporal progression. Despite its inherent muti-modal nature, current methods still focus on modeling and fusing short-term audiovisual features for individual speakers, often at frame level. In this paper we present a novel approach to active speaker detection that directly addresses the multi-modal nature of the problem, and provides a straightforward strategy where independent visual features from potential speakers in the scene are assigned to a previously detected speech event. Our experiments show that, an small graph data structure built from a single frame, allows to approximate an instantaneous audio-visual assignment problem. Moreover, the temporal extension of this initial graph achieves a new state-of-the-art on the AVA-ActiveSpeaker dataset with a mAP of 88.8\%.
    • Efficient bifacial monolithic perovskite/silicon tandem solar cells via bandgap engineering

      de Bastiani, Michele; Mirabelli, Alessandro J.; Hou, Yi; Gota, Fabrizio; Aydin, Erkan; Allen, Thomas; Troughton, Joel; Subbiah, Anand Selvin; Isikgor, Furkan Halis; Liu, Jiang; Xu, Lujia; Chen, Bin; Van Kerschaver, Emmanuel; Baran, Derya; Fraboni, Beatrice; Salvador, Michael F.; Paetzold, Ulrich W.; Sargent, E.; De Wolf, Stefaan (Nature Energy, Springer Science and Business Media LLC, 2021-01-11) [Article]
      Bifacial monolithic perovskite/silicon tandem solar cells exploit albedo—the diffuse reflected light from the environment—to increase their performance above that of monofacial perovskite/silicon tandems. Here we report bifacial tandems with certified power conversion efficiencies >25% under monofacial AM1.5G 1 sun illumination that reach power-generation densities as high as ~26 mW cm–2 under outdoor testing. We investigated the perovskite bandgap required to attain optimized current matching under a variety of realistic illumination and albedo conditions. We then compared the properties of these bifacial tandems exposed to different albedos and provide energy yield calculations for two locations with different environmental conditions. Finally, we present a comparison of outdoor test fields of monofacial and bifacial perovskite/silicon tandems to demonstrate the added value of tandem bifaciality for locations with albedos of practical relevance.
    • Response to Zöller et al.'s critique on “Potential short-term earthquake forecasting by farm-animal monitoring”

      Wikelski, Martin; Mueller, Uschi; Scocco, Paola; Catorci, Andrea; Desinov, Lev V.; Belyaev, Mikhail Y.; Keim, Daniel; Pohlmeier, Winfried; Fechteler, Gerhard; Mai, Paul Martin; Goymann, Wolfgang (Ethology, Wiley, 2021-01-11) [Article]
      Zöller et al. (Ethology, 2020) criticize our original publication (Wikelski et al., Ethology, 126(9), 2020, 931) for obvious reasons: we only observed the behavior of one group of farm animals before, during and after one earthquake series in one area of the world. It is clear that no earthquake predictions are possible, and should not be attempted, from this data set. However, what we show is that there is important information within this animal collective pertaining to potential future local forecasting of earthquakes when combined with traditional data sources. We maintain that combining Zöller et al.'s (2020) modeling tools with the adequate use of our data can stimulate novel ways of earthquake forecasting. Future studies should combine both approaches.
    • Population structure of indigenous inhabitants of Arabia

      Mineta, Katsuhiko; Goto, Kosuke; Gojobori, Takashi; Alkuraya, Fowzan S. (PLOS Genetics, Public Library of Science (PLoS), 2021-01-11) [Article]
      Modern day Saudi Arabia occupies the majority of historical Arabia, which may have contributed to ancient waves of migration out of Africa. This ancient history has left a lasting imprint in the genetics of the region, including the diverse set of tribes that call Saudi Arabia their home. How these tribes relate to each other and to the world’s major populations remains an unanswered question. In an attempt to improve our understanding of the population structure of Saudi Arabia, we conducted genomic profiling of 957 unrelated individuals who self-identify with 28 large tribes in Saudi Arabia. Consistent with the tradition of intra-tribal unions, the subjects showed strong clustering along tribal lines with the distance between clusters correlating with their geographical proximities in Arabia. However, these individuals form a unique cluster when compared to the world’s major populations. The ancient origin of these tribal affiliations is supported by analyses that revealed little evidence of ancestral origin from within the 28 tribes. Our results disclose a granular map of population structure and have important implications for future genetic studies into Mendelian and common diseases in the region.
    • Coating of Conducting and Insulating Threads with Porous MOF Particles through Langmuir-Blodgett Technique

      Rauf, Sakandar; Andrés, Miguel A.; Roubeau, Olivier; Gascón, Ignacio; Serre, Christian; Eddaoudi, Mohamed; Salama, Khaled N. (Nanomaterials, MDPI AG, 2021-01-10) [Article]
      The Langmuir-Blodgett (LB) method is a well-known deposition technique for the fabrication of ordered monolayer and multilayer thin films of nanomaterials onto different substrates that plays a critical role in the development of functional devices for various applications. This paper describes detailed studies about the best coating configuration for nanoparticles of a porous metal-organic framework (MOF) onto both insulating or conductive threads and nylon fiber. We design and fabricate customized polymethylmethacrylate sheets (PMMA) holders to deposit MOF layers onto the threads or fiber using the LB technique. Two different orientations, namely, horizontal and vertical, are used to deposit MIL-96(Al) monolayer films onto five different types of threads and nylon fiber. These studies show that LB film formation strongly depends on deposition orientation and the type of threads or fiber. Among all the samples tested, cotton thread and nylon fiber with vertical deposition show more homogenous monolayer coverage. In the case of conductive threads, the MOF particles tend to aggregate between the conductive thread’s fibers instead of forming a continuous monolayer coating. Our results show a significant contribution in terms of MOF monolayer deposition onto single fiber and threads that will contribute to the fabrication of single fiber or thread-based devices in the future.
    • An efficient and stable solar flow battery enabled by a single-junction GaAs photoelectrode.

      Fu, Hui-Chun; Li, Wenjie; Yang, Ying; Lin, Chun-Ho; Veyssal, Atilla; He, Jr-Hau; Jin, Song (Nature communications, Springer Science and Business Media LLC, 2021-01-09) [Article]
      Converting and storing solar energy and releasing it on demand by using solar flow batteries (SFBs) is a promising way to address the challenge of solar intermittency. Although high solar-to-output electricity efficiencies (SOEE) have been recently demonstrated in SFBs, the complex multi-junction photoelectrodes used are not desirable for practical applications. Here, we report an efficient and stable integrated SFB built with back-illuminated single-junction GaAs photoelectrode with an n-p-n sandwiched design. Rational potential matching simulation and operating condition optimization of this GaAs SFB lead to a record SOEE of 15.4% among single-junction SFB devices. Furthermore, the TiO2 protection layer and robust redox couples in neutral pH electrolyte enable the SFB to achieve stable cycling over 408 h (150 cycles). These results advance the utilization of more practical solar cells with higher photocurrent densities but lower photovoltages for high performance SFBs and pave the way for developing practical and efficient SFBs.
    • Metabolomic and Biochemical Analysis of Two Potato (Solanum tuberosum L.) Cultivars Exposed to In Vitro Osmotic and Salt Stresses.

      Hamooh, Bahget Talat; Sattar, Farooq Abdul; Wellman, Gordon; Mousa, Magdi Ali Ahmed (Plants (Basel, Switzerland), MDPI AG, 2021-01-09) [Article]
      Globally, many crop production areas are threatened by drought and salinity. Potato ($\textit{Solanum tuberosum}$ L.) is susceptible to these challenging environmental conditions. In this study, an in vitro approach was employed to compare the tolerance of potato cultivars 'BARI-401' (red skin) and 'Spunta' (yellow skin). To simulate ionic and osmotic stress, MS media was supplemented with lithium chloride (LiCl 20 mM) and mannitol (150 mM). GC-MS and spectrophotometry techniques were used to determine metabolite accumulation. Other biochemical properties, such as total phenols concentration (TPC), total flavonoids concentration (TFC), antioxidant capacity (DPPH free radical scavenging capacity), polyphenol oxidase (PPO), and peroxidase (POD) activities, were also measured. The two cultivars respond differently to ionic and osmotic stress treatments, with Spunta accumulating more defensive metabolites in response, indicating a higher level of tolerance. While further investigation of the physiological and biochemical responses of these varieties to drought and salinity is required, the approach taken in this paper provides useful information prior to open field evaluation.
    • Generation of iPSC lines (KAUSTi011-A, KAUSTi011-B) from a Saudi patient with epileptic encephalopathy carrying homozygous mutation in the GLP1R gene.

      Alowaysi, Maryam; Astro, Veronica; Fiacco, Elisabetta; AlZahrani, Fatema; Alkuraya, Fowzan S; Adamo, Antonio (Stem cell research, Elsevier BV, 2021-01-09) [Article]
      Glucagon-like peptide-1 receptor (GLP1R) is a seven-transmembrane-spanning helices membrane protein expressed in multiple human tissues including pancreatic islets, lung, brain, heart and central nervous system (CNS). GLP1R agonists are commonly used as antidiabetic drugs, but a neuroprotective function in neurodegenerative disorders is emerging. Here, we established two iPSC lines from a patient harboring a rare homozygous splice site variant in GLP1R (NM_002062.3; c.402 + 3delG). This patient displays severe developmental delay and epileptic encephalopathy. Therefore, the derivation of these iPSC lines constitutes a primary model to study the molecular pathology of GLP1R dysfunction and develop novel therapeutic targets.