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Synergistic co-utilization of biomass-derived sugars enhances aromatic amino acid production by engineered Escherichia coli(vol121, pg784, 2024)

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BIOTECHNOLOGY AND BIOengineering 2024年第4期121卷 1177-1177页

作者： Liu, A. Machas, M. Mhatre, A. Hajinajaf, N. Sarnaik, A. Nichols, N. Frazer, S. Wang, X. Varman, A. M. Nielsen, D. R. Biological Design Program School for Engineering of Matter Transport and Energy Arizona State University Tempe Arizona USA Chemical Engineering Program School for Engineering of Matter Transport and Energy Arizona State University Tempe Arizona USA US Department of Agriculture Agricultural Research Service National Center for Agricultural Utilization Research Peoria Illinois USA School of Life Sciences Arizona State University Tempe Arizona USA

Efficient co-utilization of mixed sugar feedstocks remains a biomanufacturing challenge, thus motivating ongoing efforts to engineer microbes for improved conversion of glucose−xylose mixtures. This study focuses on enhancing phenylalanine production by engineering Escherichia coli to efficiently co-utilize glucose and xylose. Flux balance analysis identified E4P flux as a bottleneck which could be alleviated by increasing the xylose-to-glucose flux ratio. A mutant copy of the xylose-specific activator (XylR) was then introduced into the phenylalanine-overproducing E. coli NST74, which relieved carbon catabolite repression and enabled efficient glucose−xylose co-utilization. Carbon contribution analysis through 13C-fingerprinting showed a higher preference for xylose in the engineered strain (NST74X), suggesting superior catabolism of xylose relative to glucose. As a result, NST74X produced 1.76 g/L phenylalanine from a model glucose−xylose mixture; a threefold increase over NST74. Then, using biomass-derived sugars, NST74X produced 1.2 g/L phenylalanine, representing a 1.9-fold increase over NST74. Notably, and consistent with the carbon contribution analysis, the xylR* mutation resulted in a fourfold greater maximum rate of xylose consumption without significantly impeding the maximum rate of total sugar consumption (0.87 vs. 0.70 g/L-h). This study presents a novel strategy for enhancing phenylalanine production through the co-utilization of glucose and xylose in aerobic E. coli cultures, and highlights the potential synergistic benefits associated with using substrate mixtures over single substrates when targeting specific products.

关键词： aromatic biochemicals carbon catabolite repression corn stover hydrolysate flux balance analysis phenylalanine sugar co-utilization

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Security of Cyber-Physical Systems Against Actuator Attacks through Cryptography 11

Security of Cyber-Physical Systems Against Actuator Attacks ...

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11th International Conference on Information Technology, ICIT 2023

作者： Oliveira, Samuel Leal, André B. Teixeira, Marcelo Lopes, Yuri K. Department of Exact and Technological Sciences AP Macapá Brazil Graduate Program in Electrical Engineering SC Joinville Brazil Graduate Program in Electrical Engineering Brazil

ISBN: (纸本)9798350320060

The connectivity demanded by Industry 4.0 poses new challenges for cyber-physical systems (CPS), notably bolstering resilience against cyberattacks. In this paper, the authors use the formalism of Discrete Event Systems (DES) to design an approach that aims to protect CPS against actuator attacks using event-based symmetric cryptography. In this approach, controllable events that are properly selected are encrypted before being transmitted from the controller to the plant, leading intruders to mistakenly infer the supervisor's control actions. Thus, attacks on actuators do not have the expected impact on the plant, preventing unsafe states from being reached. The proposed approach is applied to a case study from the literature, where the identification of the attack is done without causing any damage while maintaining the integrity of the system. © 2023 IEEE.

关键词： Cryptography

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Visualization of Methamphetamine-Contaminated Fingermarks on Glass Surfaces by Field Emission Scanning Electron Microscope for Forensic Investigation

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Journal of Forensic Science and Medicine 2023年第1期9卷 6-11页

作者： Sarah Aliah Amir Sarifudin Kah Haw Chang Bee Ee Khoo Ahmad Fahmi Lim Abdullah Forensic Science Program School of Health SciencesHealth CampusUniversiti Sains MalaysiaKelantanMalaysia Mechatronic Engineering Program School of Electrical and Electronic EngineeringEngineering CampusUniversiti Sains MalaysiaPenangMalaysia

Background:Fingermark is an individual’s primary identification *** is helpful in determining individuals involved in illegal activities and is frequently encountered in clandestine *** forensic investigation,the critical question to be answered is whether a fingermark was left on a surface before or after the initiation of an unlawful *** and Objectives:This study aimed to investigate the visualization of methamphetamine-contaminated fingermarks on glass surfaces and estimate the immediacy of their *** and Methods:In this study,the prior-deposition contaminated fingermarks,i.e.,fingermarks deposited a surface priorly contaminated by methamphetamine,and the postdeposition contaminated fingermarks,i.e.,fingermarks deposited on a clean surface but subsequently contaminated with methamphetamine were visualized and compared using Field Emission Scanning Electron Microscope(FESEM).Results:Under FESEM,the latent fingermarks and the crystalline structure of methamphetamine were clearly *** postdeposition contaminated fingermarks appeared in smudge conditions in all the three replicate samples,where the ridge and nonridge areas could not be *** the contrary,the prior-deposition contaminated fingermark demonstrated distinct separations between ridges and ***,the application of fingerprint powders reduced the possibility to determine the immediacy of ***:To conclude,both prior-deposition contaminated fingermarks and postdeposition contaminated fingermarks can be discriminated,providing information on the instance when a fingermark was left on a surface.

关键词： Fingermark methamphetamine scanning electron microscope visualization powder

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Atmospheric extinction coefficients and night sky brightness at ITB-Undana remote telescope site

Atmospheric extinction coefficients and night sky brightness...

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2023 International Symposium From the Universe Back to Earth: Developing Astronomy to Meet Today's Natural Challenges

作者： Yusuf, M. Yap, F. Ramadhan, S. Jatmiko, A.T.P. Ramadhan, D.G. Perhati, T. Arwinata, H.I. Satya, L. Premadi, P.W. Louk, A.C. Putra, M. Bosscha Observatory Faculty of Mathematics and Natural Sciences Institut Teknologi Bandung Indonesia Astronomy Study Program Institut Teknologi Bandung Indonesia Physics Study Program Faculty of Sciences and Engineering Universitas Nusa Cendana Indonesia

A remote telescope system has been established at Universitas Nusa Cendana, Kupang. Bosscha Observatory, Institut Teknologi Bandung (ITB), and the Physics Study program at Universitas Nusa Cendana (Undana) collaborated to develop the system. The ITB-Undana Telescope system has a QSI 616 CCD camera and BV RI Bessel filter attached to a 20-cm (f/10) Schmidt-Cassegrain reflector. Several research and public outreach activities have been conducted using the ITB-Undana remote telescope throughout 2023. When establishing a new astronomical observation site, it is imperative to conduct sky characterization and quality assessment. This process involves measuring night sky brightness and atmospheric extinction coefficients. In May 2023, we observed photometric standard stars using the absolute photometry technique with BV RI Bessel filters. We also utilized the Sky Quality Meter (SQM) to measure night sky brightness over three nights from May 24th to May 26th, 2023, to compare the sky brightness values obtained through the absolute photometry method. Our initial measurement shows a first-order extinction coefficient value ranging from kb′ = 0.269 to 0.520, kv′ = 0.216 to 0.297, kr′ = 0.019 to 0.206, and ki′ = 0.127 to 0.163, for B, V, R, and I filter, respectively. Application of extinction coefficient value in the sky field gives a mean sky brightness value in V bandpass, Vsky = 19.431 ± 0.022, with color index (B - V )sky = 0.492 ± 0.039. These night sky brightness values are suitable for measurements using the SQM. © Published under licence by IOP Publishing Ltd.

关键词： Luminance

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Mantle flow underneath the South China Sea revealed by seismic anisotropy

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National Science Review 2023年第10期10卷 54-61页

作者： Fansheng Kong Rui Gao Stephen S.Gao Kelly H.Liu Weiwei Ding Xiongwei Niu Aiguo Ruan Pingchuan Tan Jianke Fan Shaoping Lu Zhengyi Tong Liqun Cheng Wenfei Gong Yanghui Zhao Jiabiao Li Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural Resources Southern Marine Science and Engineering Guangdong Laboratory Geology and Geophysics Program Department of Geosciences and Geological and Petroleum Engineering Missouri University of Science and Technology School of Earth Sciences and Engineering Sun Yat-sen University Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences

It has long been established that plastic flow in the asthenosphere interacts constantly with the overlying lithosphere and plays a pivotal role in controlling the occurrence of geohazards such as earthquakes and volcanic ***,accurately characterizing the direction and lateral extents of the mantle flow field is notoriously difficult,especially in oceanic areas where deployment of ocean bottom seismometers(OBSs) is expensive and thus *** this study,by applying shear wave splitting analyses to a dataset recorded by an OBS array that we deployed between mid-2019 and mid-2020 in the South China Sea(SCS),we show that the dominant mantle flow field has a NNW-SSE orientation,which can be attributed to mantle flow extruded from the Tibetan Plateau by the ongoing Indian-Eurasian *** addition,the results suggest that E-W oriented flow fields observed in South China and the Indochina Peninsula do not extend to the central SCS.

关键词： mantle flow South China Sea Tibetan Plateau seismic anisotropy shear wave splitting

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Unveiling the size effect of nitrogen-doped carbon-supported copper-based catalysts on nitrate-to-ammonia electroreduction

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Nano Research 2024年第4期17卷 2438-2443页

作者： Ran Li Taotao Gao Wenxi Qiu Minghao Xie Zhaoyu Jin Panpan Li College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Institute for Advanced Study Chengdu UniversityChengdu 610106China Materials Science and Engineering Program and Walker Department of Mechanical Engineering The University of Texas at AustinAustinTexas 78712USA Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

The electrocatalytic nitrate reduction reaction(NitRR)represents a promising approach toward achieving economically and environmentally sustainable ***,it remains a challenge to regulate the size effect of electrocatalysts to optimize the catalytic activity and ammonia ***,the Cu-based catalysts were tailored at the atomic level to exhibit a size gradient ranging from single-atom catalysts(SACs,0.15–0.35 nm)to single-cluster catalysts(SCCs,1.0–2.8 nm)and nanoparticles(NPs,20–30 nm),with the aim of studying the size effect for the NO_(3)^(-)-to-NH_(3) reduction ***,the Cu SCCs exhibit enhanced metal–substrate and metal–metal interactions by taking advantageous features of Cu SACs and Cu ***,Cu SCCs achieve exceptional electrocatalytic performance for the NitRR with a maximum Faradaic efficiency of ca.96%NH_(3)and the largest yield rate of ca.1.99 mg·h^(-1)·cm^(-2) at-0.5 V *** hydrogen electrode(RHE).The theoretical calculation further reveals the size effect and coordination environment on the high catalytic activity and selectivity for the *** work provides a promising various size-controlled design strategy for aerogel-based catalysts effectively applied in various electrocatalytic reactions.

关键词： nitrate electroreduction ammonia electrosynthesis size effect single-cluster catalyst

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Characteristics of Fly Ash as a Constituent Material for Geopolymer

Characteristics of Fly Ash as a Constituent Material for Geo...

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2023 National Physics Seminar, SNF 2023

作者： Chairunnisa, N. Haryanti, N.H. Nurwidayati, R. Pratiwi, A.Y. Arnandha, Y. Saputra, Y. Hazizah, N. Civil Engineering Program Engineering Faculty Lambung Mangkurat University Banjarbaru Indonesia Physics Program Mathematics and Natural Sciences Faculty Lambung Mangkurat University Banjarbaru Indonesia Civil Engineering Post Graduated Program Engineering Faculty Lambung Mangkurat University Banjarmasin Indonesia Civil Engineering Program Engineering Faculty Tidar University Magelang Indonesia

Fly ash waste from the Asam-Asam Power Plant in South Kalimantan continues to increase. Various attempts have been made to utilize fly ash waste, among others. as a basic material for making geopolymers. Geopolymer is environmentally friendly because it replaces all cement with high Silica (Si) and Alumina (Al) wastes such as fly ash. This study aims to characterize fly ash as a raw material of geopolymer. Fly ash was filtered using 200 mesh and then heated in an oven at 105°C for 24 hours. The prepared fly ash was then tested for physical properties and compound analysis using XRF, identification of chemical bonds and functional groups using FTIR, morphology, and elements using SEM EDX. Initial and final setting time was investigated using the Vicat apparatus to determine e whether cement is undergoing proper hydration. The results indicated that the fly ash was classified to class F. That was based on the amount of SiO2 + Al2O3 + Fe2O3 of 85.91%, and the CaO content was less than 10%. Moreover, fly ash's initial and final setting time was 1072.5 and 3180 minutes, respectively. Fly ash in this research can be used as a raw material for geopolymers. © Published under licence by IOP Publishing Ltd.

关键词： Fly ash

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Preference-based jogging route selection in downtown Tokyo

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Cities and Health 2024年第3期8卷 390-404页

作者： Huang, Yumeng Eom, Sunyong Suzuki, Tsutomu Master’s Program in Risk Engineering Graduate School of Systems and Information Engineering University of Tsukuba Tsukuba Japan Division of Policy and Planning Sciences Institute of Systems and Information Engineering University of Tsukuba Tsukuba Japan

Jogging has become a popular urban outdoor recreational activity because it is inexpensive and easy. Although there are positive responses to leisure-route planning from many regions, the routes with features preferred by joggers are not commonly considered in urban planning. This article explores and evaluates methods for determining optimal urban jogging routes while considering joggers’ preferences. This study combines information about road width, green space, riverbank scenery, and various points of interest with jogging heat map data and uses a decision tree analysis to study joggers’ preferences. Next, routes with high potential considering three different patterns of points of interest and road width are selected using the vehicle routing problem analysis in ArcGIS. This method for preference-based route selection can be used to identify which links in urban road networks are attractive to runners and provide policymakers with useful information for designing built environments. © 2024 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Jogger preferences jogging route selection urban outdoor recreation vehicle routing problem

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Ultralong thermally activated delayed fluorescence based on intermolecular charge transfer induced by isomer in carbazole derivative

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Aggregate 2024年第6期5卷 392-399页

作者： Junru Chen Xianhe Zhang Zongliang Xie Bin Liu Department of Chemical and Biomolecular Engineering National University of SingaporeSingaporeSingapore Integrative Sciences and Engineering Program NUS Graduate SchoolNational University of SingaporeSingaporeSingapore Institute for Functional Intelligent Materials National University of SingaporeSingaporeSingapore

Ultralong thermally activated delayed fluorescence(UTADF)materials play an important role in realizing time-dependent color-tunable *** typical carbazole(Cz)derivatives have been reported to exhibit UTADF ***,a 10-fold difference in TADF lifetime was found between commercial Cz derivatives and the corresponding lab-synthesized ones,which indicated that UTADF may not be derived from the single Cz derivatives as *** reveal the real mechanism,we synthesized three Cz derivatives and one isomer to form three host-guest pairs for optical *** photophysical properties revealed that UTADF originated from the intermolecular charge transfer between host and guest,while the ultralong organic phosphorescence was from the *** to the rich color variations in luminescence displayed by 4-(1H-benzo[f]indol-1-yl)−4′-(9H-carbazol-9-yl)-[1,1′-biphenyl]−3,3′-dicarbonitrile/4,4′-di(9H-carbazol-9-yl)-[1,1′-biphenyl]−3,3′-dicarbonitrile(CBP-2CN)at different delay times,it can be applied to realize multi-dimensional encryption in both delay time and luminescent color.

关键词： energy transfer intermolecular charge transfer ultralong organic phosphorescence ultralong thermally activated delayed fluorescence

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Effects of Initial and Boundary Conditions on Heavy Rainfall Simulation over the Yellow Sea and the Korean Peninsula:Comparison of ECMWF and NCEP Analysis Data Effects and Verification with Dropsonde Observation

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Advances in Atmospheric sciences 2024年第9期41卷 1787-1803页

作者： Jiwon HWANG Dong-Hyun CHA Donghyuck YOON Tae-Young GOO Sueng-Pil JUNG Department of Civil Urban Earth and Environmental Engineering Ulsan National Institute of Science and TechnologyUlsan 44919South Korea Program in Atmospheric and Oceanic Sciences Princeton UniversityPrincetonNew Jersey 08544USA National Institute of Meteorological Sciences NIMSJeju 63568South Korea

This study evaluated the simulation performance of mesoscale convective system(MCS)-induced precipitation,focusing on three selected cases that originated from the Yellow Sea and propagated toward the Korean *** evaluation was conducted for the European Centre for Medium-Range Weather Forecasts(ECMWF)and National Centers for Environmental Prediction(NCEP)analysis data,as well as the simulation result using them as initial and lateral boundary conditions for the Weather Research and Forecasting ***,temperature and humidity profiles from 3D dropsonde observations from the National Center for Meteorological Science of the Korea Meteorological Administration served as validation *** showed that the ECMWF analysis consistently had smaller errors compared to the NCEP analysis,which exhibited a cold and dry bias in the lower levels below 850 *** model,in terms of the precipitation simulations,particularly for high-intensity precipitation over the Yellow Sea,demonstrated higher accuracy when applying ECMWF analysis data as the initial *** advantage also positively influenced the simulation of rainfall events on the Korean Peninsula by reasonably inducing convective-favorable thermodynamic features(i.e.,warm and humid lower-level atmosphere)over the Yellow *** conclusion,this study provides specific information about two global analysis datasets and their impacts on MCS-induced heavy rainfall simulation by employing dropsonde observation ***,it suggests the need to enhance the initial field for MCS-induced heavy rainfall simulation and the applicability of assimilating dropsonde data for this purpose in the future.

关键词： initial conditions dropsonde heavy rainfall forecast global model analysis evaluation

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