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International Journal of Geosciences 2024年第8期15卷 632-666页

作者： Colin michael Jones Retired Cambridge UK

The Roaches Grit in the UK Pennine Basin was a complex deep water deltaic sequence deposited during the Late Carboniferous glacial period. The channels of the upper part of the Roaches Grit, deposited towards the end of the cyclothem after the eustatic minimum, contain evidence for very high seasonal discharges related to strong monsoon rainfall in the catchment areas. In some channels, intense turbulence near the delta front, led to knick point recession and deep incision. These channels were filled with sediments during reduced discharge, including very large sets of cross-bedding up to 16 m thick. Channels were short-lived with frequent avulsions. Over time slightly lower discharges formed laterally migrating channels dominated by bar forms. Different discharge-controlled processes operated on the reactivated delta slope. Incised channels generated turbidity currents during floods which transported sediments directly into the basin far from the delta. Migrating channels built mouth bars;resedimentation during floods formed density currents which then deposited sediment on the lower parts of the slope.

关键词： Carboniferous Delta Climate Monsoon Rainfall ITCZ Precession

Past, Present and Future: A Role for Liquid Biofuels in Transitioning to Net Zero?

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Natural Resources 2024年第5期15卷 107-124页

作者： David michael Mousdale Beò carta Ltd. Glasgow United Kingdom

Over the last decade, the uptake rate of first-generation biofuels (ethanol and biodiesel) has decelerated as low blend limits have increased only slowly and extreme volatility in oil prices has limited investment in biofuels production infrastructure. Concerns over the environmental impacts of large-scale biofuels production combined with tariff barriers have greatly restricted the global trade in biofuels. First-generation biofuels produced either by fermentation of sugars from maize or sugarcane (ethanol) or transesterification of triglycerides (biodiesel) presently contribute less than 4% of terrestrial transportation fuel demand and techno-economic modelling foresees this only slowly increasing by 2035. With internal combustion and diesel engines widely anticipated as being phased out in favour of electric power for motor vehicles, a much-reduced market demand for biofuels is likely if global demand for all liquid fuels declines by 2050. However, second-generation, thermochemically produced and biomass-derived fuels (renewable diesel, marine oils and sustainable aviation fuel) have much higher blend limits;combined with policies to decarbonise the aviation and marine industries, major new markets for these products in terrestrial, marine and aviation sectors may emerge in the second half of the 21st century.

关键词： Biofuels Ethanol Biodiesel Renewable Diesel Sustainable Aviation Fuel Biomass

Enhanced Species Diversity Unlocked by Habitat Conservation in Agricultural Landscapes: New Perspectives on Ecological Weed Management and Sustainable Intensification—Species Diversity and Habitat Conservation

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Open Journal of Ecology 2024年第8期14卷 585-603页

作者： michael Ignatius Ferreira Directorate Plant Sciences Western Cape Department of Agriculture Elsenburg South Africa

The impulse to remain profitable by increasing agricultural production levels in view of the greater demand for food, provided impetus to production intensification. The aim of this review is to summarise current literature, reporting specifically on the impact of production intensification on habitats and yield constraints caused by weeds. Secondly, in alleviating these effects over the short term, ecological measures that enhance species diversity in conserved habitats and promote semi-natural habitats in the agricultural landscape, are discussed. In large-scale intensive agriculture, weed control is predominantly rooted in agrochemical applications in the form of herbicides. Long lasting intensive agricultural practices show discord both with the promotion of the biodiversity of microbes belowground and aboveground and with organisms involved in the breaking down of plant material. The presence of native species in the surroundings, in combination with hedgerows and field margins, with a comparatively intricate and balanced variety of plants in a sheltered environment, are essential for settlement of benign insects, particularly in the face of intensive agricultural production. The promising tactic of advantageous seed predators enables decreased herbicide applications. Crop mosaics arranged to advance compatibility at the landscape scale are important to bolster pollination services and insect management, while ecological variety in the surroundings acts as a safety net for habitat diversity. Weed control in combination with different tactics of vegetation use, comprising cover cropping, hedgerows and field margins, sets up safe havens in the landscape, and improves the diffusion of complementary life forms. Field margins perform a meaningful natural function as point of provision for forage, safe havens and distribution passageways for pollinators and insect predators. Production practices that promote more heterogeneity and combine high density semi-natural sa

关键词： Crop mosaics Field Margins Hedgerows Microbial Nitrogen Immobilization Semi-Natural Habitats Soil Microbes Weed Cross-Resistance Weed Seed Predation

Molecularly engineered lignin to polyphenol via organocatalysis as an active sunscreen ingredient

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Journal of Bioresources and Bioproducts 2024年第2期9卷 197-210页

作者： Yuanlong Guo Pengcheng Liu Lei Deng Changwei Lui michael North Gang Hu Qitian Huang Zongbao Kent Zhao Haibo Xie Department of Polymeric Materials&Engineering Guizhou UniversityGuiyang 550025China KZJ New Materials Group Guizhou Co.Ltd. Guizhou 551200China Green Chemistry Centre of Excellence Department of ChemistryUniversity of YorkYork YO105DDUK Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China

Phenolation is one of the effective strategies to synthesize lignin-based polyphenols,improve lignin’s properties,and extend its value-added applications in biological,medicinal and cosmetic ***,by taking the structural feature advantage of lignin,an effective and green strategy was developed to molecularly engineer lignin into a robust lignin-3-(2-hydroxyphenyl)propionate ester(LPPE)derivative via a transesterification reaction between 3,4-dihydrocoumarin(DHC)and the aliphatic hydroxyls in lignin under *** strategy is optimized and the novel derivative was systematically characterized by ^(1)H,^(13)C and ^(31)P nuclear magnetic resonance(NMR)and Fourier transform infrared(FT-IR)*** findings indicated that the successful introduction of 3-(2-hydroxyphenyl)propionate groups using a OH groups/DHC/organic base mo-lar ratio of 1꞉1꞉0.3 at 120℃ for 6 h increased the content of phenolic hydroxyl groups from 1.7931 to 3.0179 mmol/g,and the LPPE exhibited excellent ultraviolet-absorbing and antioxidant per-formance with up to 90%free radical scavenging activity within 20 min using 5 mg/mL of *** addition,good biocompatibility and a high Sun protection factor(SPF)value of 40.9 were achieved at 5%(w)dosage of LPPE in the cream,indicating its significant application potential in sunscreen.

关键词： Phenolation of lignin Organocatalysis 3,4-dihydrocoumarin Antioxidant Sunscreen cream

Insights into optimizing exosome therapies for acute skin wound healing and other tissue repair

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Frontiers of Medicine 2024年第2期18卷 258-284页

作者： Tianjing Sun Mo Li Qi Liu Anyong Yu Kun Cheng Jianxing Ma Sean Murphy Patrick michael McNutt Yuanyuan Zhang Department of Emergency Affiliated Hospital of Zunyi Medical UniversityZunyi563003China Department of Nephrology Affiliated Hospital of Zunyi Medical UniversityZunyi563003China Division of Pharmacology and Pharmaceutical Sciences School of PharmacyUniversity of Missouri-Kansas CityKansas CityMO64108USA Department of Biochemistry Wake Forest University School of MedicineWinston-SalemNC27157USA Wake Forest Institute of Regenerative Medicine Wake Forest School of MedicineWinston-SalemNC27109USA

Exosome therapy holds great promise as a novel approach to improve acute skin wound *** review provides a comprehensive overview of the current understanding of exosome biology and its potential applications in acute skin wound healing and ***,small extracellular vesicles secreted by various stem cells,have emerged as potent mediators of intercellular communication and tissue *** advantage of exosome therapy is its ability to avoid potential risks associated with stem cell therapy,such as immune rejection or stem cells differentiating into unwanted cell ***,further research is necessary to optimize exosome therapy,not only in the areas of exosome isolation,characterization,and engineering,but also in determining the optimal dose,timing,administration,and frequency of exosome ***,optimization of exosome therapy is critical for the development of more effective and safer exosome-based therapies for acute skin wound healing and other diseases induced by cancer,ischemia,or *** review provides valuable insights into the potential of exosome therapy and highlights the need for further research to optimize exosome therapy for clinical use.

关键词： exosomes stem cells therapeutic impact skin wound healing

Masting promotes transformation from predation to mutualism in an oak-weevil-rodent system

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Science China(Life Sciences) 2024年第7期67卷 1514-1524页

作者： Hongmao Zhang Hongyu Niu michael ASteele Liqing Peng Huimin He Aoqiang Li Xianfeng Yi Hongjun Li Zhibin Zhang Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture Institute of ZoologyChinese Academy of SciencesBeijing 100101China Department of Biology Wilkes UniversityWilkes-Barre 18766USA School of Life Sciences Qufu Normal UniversityQufu 273165China

The significance of ecological non-monotonicity(a function whose first derivative changes signs)in shaping the structure and functions of the ecosystem has recently been recognized,but such studies involving high-order interactions are ***,we have proposed a threetrophic conceptual diagram on interactions among trees,rodents,and insects in mast and non-mast years and tested the hypothesis that oak(Quercus wutaishanica)masting could result in increased mutualism and less predation in an oak-weevil-rodent system in a warm temperate forest of *** 14-year dataset revealed that mast years coincided with a relatively low rodent abundance but a high weevil *** not only benefited seedling recruitment of oaks through increased dispersal by rodents but also a decrease in predation by rodents and weevils,as well as an increase in the overwintering survival of *** appeared to have increased weevil survival by reducing predation of infested acorns by *** results suggest that masting benefits all participants in the plant-insect-rodent system by increasing mutualism and reducing predation behavior(i.e.,a non-monotonic function).Our study highlights the significance of masting in maintaining the diversity and function of the forest ecosystem by facilitating the transformation from predation to mutualism among trophic species.

关键词： antagonism ecological non-monotonicity mutualism seed-weevil-rodent system seedling recruitment rodent overwintering survival weevil survival

Correcting distortions of thin-walled machined parts by machine hammer peening

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Chinese Journal of Aeronautics 2024年第6期37卷 439-453页

作者： Aitor MADARIAGA Mikel CUESTA Gorka ORTIZ-DE-ZARATE Eneko SAENZ-DE-ARGANDONA Denis SORIANO michael B.PRIME Pedro Jose ARRAZOLA Department of Materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom Mechanical and Industrial Production Department Faculty of EngineeringMondragon UnibertsitateaArrasate 20500Spain Los Alamos National Laboratory Los AlamosNew MexicoUSA

Thin-walled aerostructural components frequently get distorted after the machining *** to correct distortions or eventually rejecting parts significantly increases the *** paper proposes a new approach to correct distortions in thin-walled components by strategically applying hammer peening on target surfaces of a machined *** alloy 7475-T7351 was chosen for this *** study was divided in two ***,the residual stresses(RS)induced by four different pneumatic hammer peening conditions(modifying the stepover distance and initial offset)were characterised in a test coupon,and one of the conditions was selected for the next *** the second stage,a FEM model was used to predict distortions caused by machining in a representative ***,the RS induced by hammer peening were included in an FEM model to define two hammer peening strategies(varying the coverage area)to analyse the capability to reduce *** workpieces were machined and then treated with the simulated hammer peening strategies for experimental *** in the test coupon showed that pneumatic hammer peening can generate high compressive RS(-50 to350 MPa)up to 800 lm depth,with their magnitude increasing with a reduced stepover *** of hammer peening over 4% of the surface of the representative workpiece reduced the machininginduced distortions by 37%,and a coverage area of 100% led to and overcorrection by a factor of *** confirms that hammer peening can be strategically applied(in target areas and changing the percentage of coverage)to correct low or severe distortions.

关键词： Aeronautics Machining,Hammer Peening Aluminium alloy Distortions Residual Stress

A review of control strategies used for morphing aircraft applications

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Chinese Journal of Aeronautics 2024年第4期37卷 436-463页

作者： Muhammed S.PARANCHEERIVILAKKATHIL Jafar S.PILAKKADAN Rafic M.AJAJ Mohammadreza AMOOZGAR Davood ASADI Yahya ZWEIRI michael I.FRISWELL Department of Aerospace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Aerospace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Mechanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Department of Aerospace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple Proportional Integral Derivative(PID) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.

关键词： Control strategies Morphing aircraft Shape morphing Flight dynamics Aeroelasticity

Role of buccal mucosa graft ureteroplasty in the surgical management of pyeloplasty failure

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Asian Journal of Urology 2024年第3期11卷 373-376页

作者： Matthew Lee Elizabeth Nagoda David Strauss Matthew Loecher michael Stifelman Lee Zhao Department of Urology Lewis Katz School of MedicineTemple UniversityPhiladelphiaPAUSA Department of Urology Hackensack Meridian School of MedicineHackensack University Medical CenterHackensackNJUSA Department of Urology New York University Grossman School of MedicineNew York University Langone Health SystemNew YorkNYUSA

Objective:Secondary pyeloplasty for recurrent ureteropelvic junction obstructions may be a safe and feasible surgical option for *** study aimed to demonstrate outcomes of utilizing a non-transecting buccal mucosa graft ureteroplasty for management of recurrent ureteropelvic junction obstruction after prior failed ***:We performed a retrospective review of our Collaborative of Reconstructive Robotic Ureteral Surgery database for all consecutive patients who underwent buccal mucosa graft ureteroplasty between April 2012 and June 2022 for management of recurrent ureteropelvic junction obstructions after prior failed *** primary outcome included surgical success which was defined as the absence of flank pain and no obstruction on ***:Overall,ten patients were included in our *** median stricture length was 2.5(interquartile range[IQR]1.8-4.0)*** median operative time was 230.5(IQR 199.5-287.0)min and median estimated blood loss was 50.0(IQR 28.8-102.5)*** a median follow-up of 10.3(IQR 6.2-14.8)months,80%of patients were surgically successful and there were no major(ClavieneDindo Grade>2)***:Buccal mucosa graft ureteroplasty is a valuable non-transecting surgical option for patients with recurrent ureteropelvic junction obstructions who failed prior pyeloplasty and has comparable outcomes to the literature regarding standard transecting techniques.

关键词： Ureteral obstruction Buccal mucosagraft Pyeloplasty Robotic Stricture

Rbfox1 controls alternative splicing of focal adhesion genes in cardiac muscle cells

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Journal of Molecular Cell Biology 2024年第1期16卷 54-65页

作者： Peter Zorn Jaime Calvo Sánchez Tala Alakhras Barbara Schreier michael Gekle Stefan Hüttelmaier Marcel Köhn Junior Group‘Non-coding RNAs and RBPs in Human Diseases’ Medical FacultyUniversity of Halle–Wittenberg06120 Halle(Saale)Germany Julius Bernstein Institute of Physiology Medical FacultyUniversity of Halle–Wittenberg06112 Halle(Saale)Germany Institute of Molecular Medicine Medical FacultyUniversity of Halle–Wittenberg06120 Halle(Saale)Germany

Alternative splicing is one of the major cellular processes that determine the tissue-specific expression of protein ***,it remains challenging to identify physiologically relevant and tissue-selective proteins that are generated by alternative ***,we investigated the target spectrum of the splicing factor Rbfox1 in the cardiac muscle context in more *** using a combination of in silico target prediction and in-cell validation,we identified several focal adhesion proteins as alternative splicing targets of *** focused on the alternative splicing patterns of vinculin(metavinculin isoform)and paxillin(extended paxillin isoform)and identified both as potential Rbfox1 *** analyses suggested that both isoforms are promoted by Rbfox1 due to binding in the *** adhesions play an important role in the cardiac muscle context,since they mainly influence cell shape,cytoskeletal organization,and cell–matrix *** data confirmed that depletion of Rbfox1 changed cardiomyoblast morphology,cytoskeletal organization,and multinuclearity after differentiation,which might be due to changes in alternative splicing of focal adhesion ***,our results indicate that Rbfox1 promotes alternative splicing of focal adhesion genes in cardiac muscle cells,which might contribute to heart disease progression,where downregulation of Rbfox1 is frequently observed.

关键词： Rbfox1 alternative splicing focal adhesion cardiac muscle cells