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Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming Ma chris J.Pickard Hanyu Liu Maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard Materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of Materials Science & Metallurgy University of Cambridge Advanced Institute for Materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. these molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. this surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

Experimental and analytical investigation on friction resistance force between buried coated pressurized steel pipes and soil

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 615-629页

作者： Shaurav ALAM tanvir MANZUR John MAttHEWS chris BARtLEtt Erez ALLOUCHE Brent KEIL John KRAFt Department of Civil Engineering and Construction Engineering technology Louisiana Tech UniversityRustonLA 71270USA Department of Civil Engineering Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh Georgia tech Research Institute AtlantaGA 30332USA Stantec Inc. Edmonton T5J0K4Canada North West Pipe Company VancouverWA 98684USA

this paper presents an analytical approach for estimating frictional resistance to pipe movement at soil and external pipe surface of buried coated pressurized steel pipes relative to the internal thrust *** proposed analytical method was developed based on 36 experiments,which involved three coating types(cement mortar(CM),polyurethane type-I(Pt-I),prefabricated plastic tape(PPt))on pipes’surfaces,three different soils(pea-gravel(PG),sand(S),silty-clay(SC)),and four simulated over burden depths above the pipe’s *** showed frictional resistance decreased with increasing over burden depth above the pipe’s *** degree of frictional resistance at the pipe-soil interface was found to be in the order of PG>SC>S for all coating variations and overburden *** coated pipe buried in all three types of soil produced significantly higher frictional resistance as compared to other coating *** on experimental data,the developed analytical introduced a dimensionless factor“Z”,which included effects of types of coatings,soil,and overburden depths for simplified rapid *** showed that the method provided a better prediction of frictional resistance forces,in comparison to previous analytical methods,which were barely close in predicting friction resistance for different coating variations,soil types,and overburden *** resistance force values reported herein could be considered conservative.

关键词： friction resistance force thrust force coated pressurized steel pipe soil type overburden depth

Nitrate reduction capacity of the oral microbiota is impaired in periodontitis:potential implications for systemic nitric oxide availability

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International Journal of Oral Science 2024年第1期16卷 52-61页

作者： Bob t.Rosier William Johnston Miguel Carda-Diéguez Annabel Simpson Elena Cabello-Yeves Krystyna Piela Robert Reilly Alejandro Artacho chris Easton Mia Burleigh Shauna Culshaw Alex Mira Department of Genomics and Health FISABIO FoundationCenter for Advanced Research in Public HealthValenciaSpain Department of Biological and Biomedical Sciences Glasgow Caledonian UniversityGlasgowUK Oral Sciences University of Glasgow Dental SchoolSchool of MedicineDentistry and NursingCollege of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowUK Sport and Physical Activity Research Institute University of the West of ScotlandBlantyreScotland Instituto de Biomedicina de Valencia Consejo Superior de Investigaciones Científicas(IBV-CSIC)ValenciaSpain CIBER Center for Epidemiology and Public Health MadridSpain

the reduction of nitrate to nitrite by the oral microbiota has been proposed to be important for oral health and results in nitric oxide formation that can improve cardiometabolic conditions. Studies of bacterial composition in subgingival plaque suggest that nitrate-reducing bacteria are associated with periodontal health, but the impact of periodontitis on nitrate-reducing capacity(NRC)and, therefore, nitric oxide availability has not been evaluated. the current study aimed to evaluate how periodontitis affects the NRC of the oral microbiota. First, 16S rRNA sequencing data from five different countries were analyzed, revealing that nitratereducing bacteria were significantly lower in subgingival plaque of periodontitis patients compared with healthy individuals(P tasets with n = 20–82 samples per dataset). Secondly, subgingival plaque, saliva, and plasma samples were obtained from 42 periodontitis patients before and after periodontal treatment. the oral NRC was determined in vitro by incubating saliva with 8 mmol/L nitrate(a concentration found in saliva after nitrate-rich vegetable intake) and compared with the NRC of 15healthy individuals. Salivary NRC was found to be diminished in periodontal patients before treatment(P t recovered to healthy levels 90 days post-treatment. Additionally, the subgingival levels of nitrate-reducing bacteria increased after treatment and correlated negatively with periodontitis-associated bacteria(P t effect of periodontal treatment on the baseline saliva and plasma nitrate and nitrite levels was found, indicating that differences in the NRC may only be revealed after nitrate intake. Our results suggest that an impaired NRC in periodontitis could limit dietary nitrate-derived nitric oxide levels, and the effect on systemic health should be explored in future studies.

关键词： impaired intake nitrate

Individual consistency in spatiotemporal characteristics of migratory Whimbrels in the East Asian-Australasian Flyway

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Avian Research 2024年第3期15卷 308-315页

作者： Siwei An Fenliang Kuang Wei Wu chris J.Hassell Jonathan t.Coleman Zijing Gao Xuena Sun Yue Yuan Grace Maglio Kar-Sin K.Leung Xuesong Feng Zhijun Ma Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Coastal Ecosystems Research Station of the Yangtze River EstuaryInstitute of Biodiversity ScienceSchool of Life SciencesFudan UniversityShanghai200433China School of Chemistry and Environment Yunnan Minzu UniversityKunming650504China Shanghai Chongming Dongtan Nature Reserve Administration Center ChongmingShanghai202183China Global Flyway Network PO Box 3089BroomeWA 6725Australia Australasian Wader Studies Group BroomeWA6725Australia Queensland Wader Study Group Shailer ParkQLD4128Australia Hong Kong Waterbirds Ringing Group Hong Kong999077China

Many migratory birds exhibit interannual consistency in migration schedules,routes and stopover *** the interannual consistency in spatiotemporal characteristics helps understand the maintenance of migration and enables the implementation of targeted conservation *** tracked the migration of Whimbrel(Numenius phaeopus)in the East Asian-Australasian Flyway and collected spatiotemporal data from individuals that were tracked for at least two *** non-parametric tests were used to compare the interannual variations in the dates of departure from and arrival at breeding/nonbreeding sites,and the inter-annual variation in the longitudes when the same individual across the same *** exhibited a high degree of consistency in the use of breeding,nonbreeding,and stopover sites between *** variation of arrival dates at nonbreeding sites was significantly larger than that of the departure dates from nonbreeding and breeding *** used stopover sites by the same individuals in multiple years were concentrated in the Yellow Sea coast during northward migration,but were more widespread during southward *** stopover duration at repeatedly used sites was significantly longer than that at sites used only *** flying across the Yellow Sea,Whimbrels breeding in Sakha(Yakutia)exhibited the highest consistency in migration routes in both autumn and ***,the consistency in migration routes of Yakutia breeding birds was generally higher than that of birds breeding in *** results suggest that the northward migration schedule of the Whimbrels is mainly controlled by endogenous factors,while the southward migration schedule is less affected by endogenous *** repeated use of stopover sites in the Yellow Sea coast suggests this region is important for the migration of Whimbrel,and thus has high conservation value.

关键词： Consistency Migration route Migration timing Shorebird

Predictive modeling for post operative delirium in elderly

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World Journal of Gastrointestinal Oncology 2024年第9期16卷 3761-3764页

作者： chris B Lamprecht Abeer Dagra Brandon Lucke-Wold Lillian S.Wells Department of Neurosurgery University of FloridaGainevilleFL 32610United States

Delirium,a complex neurocognitive syndrome,frequently emerges following surgery,presenting diverse manifestations and considerable obstacles,especially among the *** editorial delves into the intricate phenomenon of postoperative delirium(POD),shedding light on a study that explores POD in elderly individuals undergoing abdominal malignancy *** study examines pathophysiology and predictive determinants,offering valuable insights into this challenging clinical *** the synthetic minority oversampling technique,a predictive model is developed,incorporating critical risk factors such as comorbidity index,anesthesia grade,and surgical *** is an urgent need for accurate risk factor identification to mitigate POD *** specific to elderly patients with abdominal malignancies,the findings contribute significantly to understanding delirium pathophysiology and *** research is warranted to establish standardized predictive for enhanced generalizability.

关键词： Post-operative delirium Elderly delirium Neurocognitive syndrome Neurotransmitters Abdominal malignancy Predictive model Synthetic minority oversampling technique

Proliferating Satellite Constellations Pose Astronomical and Environmental Challenges

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Engineering 2024年第5期36卷 9-11页

作者： chris Palmer Senior technology Writer

On 6 October 2023,Amazon(Seattle,WA,USA)launched two prototype satellites into low-Earth orbit[1],the inaugural orbiters of Project Kuiper,a constellation of 3236 satellites that will work together to eventually deliver internet to tens of millions of customers *** Kuiper,named for the belt of ice,rock,and dwarf planets beyond Neptune,is smaller in number than the so-called mega-constellations built by SpaceX(Hawthorne,CA,USA),OneWeb(London,UK),and others,Amazon plans to loft its Kuiper satellites into orbit at a historic pace over the next few years.

关键词： Amazon eventually planet

Unprecedented JWSt Observations Contest Cosmological Canons

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Engineering 2024年第6期37卷 6-9页

作者： chris Palmer Senior technology Writer

After more than 18 months of nearly flawless operation,the James Webb Space telescope(JWSt)continues to deliver amazement,making unexpected discoveries,adding new wrinkles to known phenomena,and calling into question long-held theories of how the universe works.“the instruments are working amazingly well,in essentially all cases better than expected,”said Garth Illingworth,professor emeritus of astronomy and astrophysics at the University of California,Santa Cruz(CA,USA),and one of the three originators of the mission over three decades ago.“It has exceeded every one of its performance requirements,which is truly amazing when you think about how complex it is.”that complexity has included three decades of planning,design,and construction,followed by launch and maneuvering 1.5106 km from Earth to its second Lagrange(L2)orbit,unfolding and locking into position the 18 segments of its 6.5 m diameter main mirror,and deploying 8 motors,90 cables,and some 400 pulleys to unfurl its fragile sunshield[1,2].

关键词： universe Observation Cosmo

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对臭氧层造成破坏的违禁化学物质仍在增加

Engineering 2024年第4期35卷 7-9页

作者： chris Palmer Senior technology Writer

As reported in a study published in April 2023,some of the globally banned chemicals that decimated the Earth’s ozone layer are still finding their way into the atmosphere[1].While unlikely to greatly impact global ozone levels,the continuing pollution has scientists concerned for two reasons:the chemicals,called chlorofluorocarbons(CFCs),are potent greenhouse gases,and,perhaps more worrying,the sources of the surprising emissions remain unidentified.

关键词： pollution ozone globally

“泰坦”号潜水器--通向死亡的“海洋之门”

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Engineering 2024年第1期32卷 1-3页

作者： chris Palmer Senior technology Writer

Early on the morning of June 18,2023,far off the shore of Newfoundland,Canada,the titan deep-sea submersible began its descent into the depths of the North *** was titan’s inventor and pilot,Stockton Rush,along with four“mission specialists,”several of whom may have paid as much as 250000 USD to accompany Rush on a voyage to the site of the infamous titanic shipwreck on the ocean *** two hours later.

关键词：泰坦 depths ocean