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Advancements and Applications of 4D Bioprinting in Biomedical Science 被引量:1
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作者 Hakan Eskizengin Can Ergun 《Chinese Journal of Polymer Science》 2025年第1期18-39,I0006,共23页
The constraints of traditional 3D bioprinting are overcome by 4D bioprinting integrating with adaptable materials over time,resulting in dynamic,compliant,and functional biological structures.This innovative approach ... The constraints of traditional 3D bioprinting are overcome by 4D bioprinting integrating with adaptable materials over time,resulting in dynamic,compliant,and functional biological structures.This innovative approach to bioprinting holds great promise for tissue engineering,regenerative medicine,and advanced drug delivery systems.4D bioprinting is a technology that allows for the extension of 3D bioprinting technology by making predesigned structures change after they are fabricated using smart materials that can alter their characteristics via stimulus,leading to transformation in healthcare,which is able to provide precise personalized effective medical treatment without any side effects.This review article concentrates on some recent developments and applications in the field of 4D bioprinting,which can pave the way for groundbreaking advancements in biomedical sciences.4D printing is a new chapter in bioprinting that introduces dynamism and functional living biological structures.Therefore,smart materials and sophisticated printing techniques can eliminate the challenges associated with printing complex organs and tissues.However,the problems with this process are biocompatibility,immunogenicity,and scalability,which need to be addressed.Moreover,numerous obstacles have been encountered during its widespread adoption in clinical practice.Therefore,4D bioprinting requires improvements in future material science innovations and further development in printers and manufacturing techniques to unlock its potential for better patient care and outcomes. 展开更多
关键词 Tissue engineering Four-dimensional bioprinting Three-dimensional bioprinting HYDROGELS Stimuli sensitive polymers
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Phytochemical fingerprinting of phytotoxins as a cutting-edge approach for unveiling nature's secrets in forensic science
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作者 Nabil Zakaria Ashraf S.A.El-Sayed Mostafa G.Ali 《Natural Products and Bioprospecting》 2025年第1期71-95,共25页
The integration of phytochemistry into forensic science has emerged as a groundbreaking frontier,providing unprecedented insights into nature's secrets through the precise application of phytochemical fingerprinti... The integration of phytochemistry into forensic science has emerged as a groundbreaking frontier,providing unprecedented insights into nature's secrets through the precise application of phytochemical fingerprinting of phytotoxins as a cutting-edge approach.This study explores the dynamic intersection of phytochemistry and forensic science,highlighting how the unique phytochemical profiles of toxic plants and their secondary metabolites,serve as distinctive markers for forensic investigations.By utilizing advanced techniques such as Ultra-High-Performance Liquid Chromatography(UHPLC)and High-Resolution Mass Spectrometry(HRMS),the detection and quantification of plant-derived are made more accurate in forensic contexts.Real-world case studies are presented to demonstrate the critical role of plant toxins in forensic outcomes and legal proceedings.The challenges,potential,and future prospects of integrating phytochemical fingerprinting of plant toxins into forensic science were discussed.This review aims to illuminate phytochemical fingerprinting of plant toxins as a promising tool to enhance the precision and depth of forensic analyses,offering new insights into the complex stories embedded in plant toxins. 展开更多
关键词 Forensic phytochemistry Phytochemical fingerprinting Plant toxins Advanced chromatography
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Building a Culture of Care in Laboratory Animal Science through practicing“remembrance”:A reflection on local practices in Sri Lanka
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作者 A.D.D.S.Amarasekara K.A.A.U.Karunarathna +3 位作者 W.M.K.M.Ratnayake A.A.I.Senevirathne P.Yapa M.Gunatilake 《Animal Models and Experimental Medicine》 2025年第9期1725-1728,共4页
Remembrance activities can support the Culture of Care(CoC)in Laboratory Animal Science(LAS)not only by promoting a culture of respect,gratitude and thankfulness for animal life but also by helping the emotional proce... Remembrance activities can support the Culture of Care(CoC)in Laboratory Animal Science(LAS)not only by promoting a culture of respect,gratitude and thankfulness for animal life but also by helping the emotional processing and healing of lab animal researchers and animal facility staff.Even though remembrance activities are practiced in many parts of the world,we did not come across any reported cases in Sri Lanka before 2022.Therefore,here,we report on the various remembrance activities and practices observed within our local scientific community. 展开更多
关键词 Asia Laboratory Animal Day Culture of Care Lab animal welfare Remembrance
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Reconstruction of the surface of carbon paper by electrochemical exfoliation to produce a binder-free electrode for Zn-ion storage
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作者 Iqra Ashraf Awais Ahmad +4 位作者 Ibrahim A.Shaaban Tensangmu Lama Tamang Muhammad Sufyan Javed Fan Haosen Fang Li 《新型炭材料(中英文)》 北大核心 2026年第1期184-195,共12页
Zinc-ion supercapacitors(ZISCs)have received considerable interest for energy storage because of their low cost,high safety,and minimal environmental impact.However,they have a low energy density and poor cycling perf... Zinc-ion supercapacitors(ZISCs)have received considerable interest for energy storage because of their low cost,high safety,and minimal environmental impact.However,they have a low energy density and poor cycling performance.The design of a better cathode material is needed to overcome these limitations.A simple method was used to synthesize binder-free electrochemically exfoliated carbon paper(EECP)which modifies the surface of the paper by introducing oxygen functional groups and thus improves its pseudocapacitance.When used in a Zn-ion supercapacitor(ZISC),an EECPbased cathode provides a large surface area and quick charge transfer.As a result,the ZISC had remarkable charge storage properties and had a dominant capacitive-type charge storage mechanism with 78.8%retention of capacity at 10 mV/s of the total storage.Furthermore,at 1 A/g,the EECP electrode had a maximum capacitance of 252.5 F/g.The EECP electrode retained 81.7%of its capacitance after 10000 cycles,indicating its promise for use in the growing renewable energy sector.A ZISC was also constructed using EECP as the positive electrode and Zn as the negative electrode with a 1 mol L^(−1) ZnSO_(4) electrolyte.It had a capacitance of 186.22 F/g at 1 A/g and a 97.01%retention rate after 10000 cycles.It also had an excellent energy density of 46.6 Wh/kg at a power density of 500.4 W/kg.The material is therefore suitable for use in high-rate next-generation ZISCs. 展开更多
关键词 Carbon paper Electrochemical exfoliation Cathode material Zinc-ion supercapacitor
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Preparation of ZnO Nanoparticles Incorporated into Cross-Linked Poly (Methyl Methacrylate) (PMMA) Polymer and Its Biological Application
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作者 Nazeeha S.Alkayal 《Journal of Polymer Materials》 2026年第1期357-370,共14页
The development of polymer nanoparticle composites with enhanced thermal and antibacterial properties is essential for next-generation biomedical materials.However,conventional polymers often exhibit limited bioactivi... The development of polymer nanoparticle composites with enhanced thermal and antibacterial properties is essential for next-generation biomedical materials.However,conventional polymers often exhibit limited bioactivity and poor resistance to degradation,restricting their functional applications.The novelty of this study involves the combination of the bio-derived cross-linker 2,5-bis(aminomethyl)furan(BAF)into poly(methylmethacrylate)PMMA to form a cross-linked network incorporated with various ratios of ZnO nanoparticles(ZnO NPs),resulting in improved biological and thermal properties.The surface morphologies,material crystallinity,and thermal degradation properties of the synthesized BAF-PMMA/ZnO were investigated using Scanning Electron microscopy(SEM),Energy-Dispersive X-ray spectroscopy(EDX),X-ray diffraction(XRD),andThermogravimetric characterization technique(TGA),respectively.The prepared BAF-PMMA/ZnO nanocomposites showed an enhancement in the crystallinity after increasing the ratio of ZnO NPs compared to the amorphous cross-linked BAF-PMMA polymer.The thermal stability of nanocomposites was significantly enhanced after the introduction of ZnO NPs into crosslinked BAF-PMMA polymer.The resultant nanocomposites BAF-PMMA/ZnO were examined as antibacterial agents against the Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)bacterial strains.The results showed that most BAF-PMMA/ZnO nanocomposites have antibacterial activity against both bacterial species compared to the pure cross-linked BAF-PMMA polymer.The BAF-PMMA/ZnO 10 wt.%sample shows the highest inhibition zone of(16.3±0.33)against E.coli.These outcomes demonstrate that such nanocomposites offer a viable pathway towardmultipurpose biomaterials with exceptional structural and biological features. 展开更多
关键词 Cross-linked PMMA FURAN ZnO nanoparticle antibacterial E.COLI S.aureus
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Effects of non-plastic silt and soil aging on re-liquefaction resistance of sandy soils
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作者 Tadao Enomoto 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1601-1620,共20页
To investigate the influencesof non-plastic silt and soil aging on the re-liquefaction resistance of sands,a series of undrained triaxial tests was performed on sand-silt mixtures with finescontent ranging from 0%to 1... To investigate the influencesof non-plastic silt and soil aging on the re-liquefaction resistance of sands,a series of undrained triaxial tests was performed on sand-silt mixtures with finescontent ranging from 0%to 100%,as well as on undisturbed and reconstituted non-plastic sandy soils retrieved from earth structures with a history of earthquake-induced damage.The specimens on sand-silt mixtures were produced under an initial degree of compaction of 95%.In these tests,liquefaction histories were applied three times to a single specimen under the same cyclic stress ratio after the respective consolidation stages with the measurements of the shear wave velocities.The following conclusions can be obtained from the test results:(1)The liquefaction resistance obtained in the firstto third cyclicloading stages decreased initially with increasing finescontent up to about 45%,while it increased afterward.Therefore,the susceptibility of sands containing a relatively large amount of non-plastic silt to reliquefaction may be more significantthan that of clean sands;(2)The liquefaction resistance and the shear wave velocity decreased significantlyduring the second cyclic-loading stage and after the second consolidation,respectively,despite an increase in the specimen density caused by the first liquefaction history,while they increased in the third stage.The possible reason for this change would be the disturbance of soil structures due to liquefaction,which may be partially evaluated by the volumetric strain during the respective consolidation stages,and the stress-induced anisotropy formed in the previous liquefaction stage;and(3)The liquefaction resistance and the shear wave velocity of the undisturbed specimens,which were measured in the firstto third stages,were larger than those of the reconstituted ones due to the aging effects,respectively.That is,the aging effects may not necessarily be eliminated by the subsequent liquefaction history and may remain partially in some cases. 展开更多
关键词 Multiple liquefaction Non-plastic silt Undisturbed non-plastic sandy soil Aging effect Triaxial liquefaction test Shear wave velocity
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An evidence-based review of the ethnomedicinal,phytochemical,and pharmacological properties of Typhonium flagelliforme
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作者 Siti Aishah Mohammad Amin Yeun-Mun Choo 《Traditional Medicine Research》 2026年第5期1-13,共13页
Typhonium flagelliforme(TF)is a Southeast Asian medicinal plant traditionally used for cancer,respiratory disorders,gastrointestinal complaints,wound healing,inflammation,and general health.Contemporary studies valida... Typhonium flagelliforme(TF)is a Southeast Asian medicinal plant traditionally used for cancer,respiratory disorders,gastrointestinal complaints,wound healing,inflammation,and general health.Contemporary studies validate these uses,showing potent anticancer,immunomodulatory,anti-inflammatory,gastroprotective,antibacterial,antioxidant,and wound-healing activities.Ethanol,dichloromethane,methanol,and ethyl acetate extracts exhibit strong cytotoxicity against breast(MCF-7,T47D),lung(NCI-H23),colon(WiDr),and leukemia(CEM-ss,WEHI-3)cells via apoptosis,telomerase inhibition,HER2/neu and BCL-2 suppression,and antiangiogenesis.Notably,2-octenoic acid and 2-hexenoic acid show exceptional activity(IC₅₀=2.66 and 3.10μg/mL)against MCF-7 cells.TF also restores lymphocyte proliferation,enhances macrophage activity,increases both CD4+and CD8+T-cell levels,and modulates cytokines(TNF-α,IL-1α,IL-10).Gastroprotective,anti-ulcer,antibacterial,antioxidant,and wound-healing effects further support traditional claims.Key phytochemicals include flavonoids(isovitexin,kaempferol,vitexin),phenolics(vanillin,4-hydroxybenzaldehyde),phytosterols(β-sitosterol,campesterol,stigmasterol,daucosterol),chlorophyll derivatives(pheophorbides),and long-chain fatty acids(linoleic,linolenic,oleic,stearic).These findings highlight TF as a source of multifunctional bioactive compounds,warranting further pharmacokinetic,safety,and clinical evaluation for evidence-based therapeutic development. 展开更多
关键词 Typhonium flagelliforme ETHNOMEDICINE PHYTOCHEMICALS anticancer activity IMMUNOMODULATION
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Homret Ghannam Post-collisional Granites in the Eastern Desert of Egypt:Petrogenesis,Geodynamic Evolution,and Rare-metal Significance
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作者 Elwan I.WAHEED Abdel-Karim M.ABDEL-AAL +2 位作者 Azer K.MOKHLES Zamzam A.SARA Shaimaa A.EL-SHAFEI 《Acta Geologica Sinica(English Edition)》 2026年第1期99-120,共22页
Homret Ghannam alkali feldspar granite(HGAFG)in the central Eastern Desert(CED)of Egypt represents a distinctive example of late Neoproterozoic magmatism in the Arabian-Nubian Shield(ANS).This study integrates field o... Homret Ghannam alkali feldspar granite(HGAFG)in the central Eastern Desert(CED)of Egypt represents a distinctive example of late Neoproterozoic magmatism in the Arabian-Nubian Shield(ANS).This study integrates field observations,petrography,mineral chemistry(EMPA),and whole-rock geochemistry to investigate its petrogenesis,geodynamic evolution,and rare-metal potential.HGAFG comprises two cogenetic varieties,alkali feldspar granite and riebeckite-bearing granite,hosting rare-metal minerals such as zircon,fluorite,columbite and apatite.HGAFG exhibits diagnostic A-type geochemical characteristics,including high SiO₂contents(73.81-77.86 wt%),metaluminous to mildly peralkaline composition(ASI:0.92-1.03),enrichment in HFSE(Zr≈791.80 ppm,Nb≈68.12 ppm,Y≈90.81 ppm)andΣREE(103.40-475.57 ppm),and pronounced negative Eu anomalies(Eu/Eu^(*)=0.07-0.20).Zircon saturation thermometry yields high crystallization temperatures(TZr≈908.87℃)and low emplacement pressures(1.46 kbar)under reducing conditions(ƒO_(2)≈−11.5).The mineralogical and geochemical results reveal that HGAFG originated from a hybrid,fluorine-rich magma generated by anatexis of lower crust,followed by extensive fractional crystallization,during late post-collisional extension associated with lithospheric delamination.The reduced nature and fluorine enrichment of HGAFG magma promoted the mineralization of Nb-Ta-REE phases,highlighting its significance as a fertile,high-temperature product of the terminal magmatic stage in ANS evolution. 展开更多
关键词 alkaline granites riebeckite arfvedsonite COLUMBITE PETROGENESIS Homret Ghannam
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Bio-inspired magnetic soft robots with omnidirectional climbing for multifunctional biomedical applications
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作者 Ruomeng Xu Xianli Wang +2 位作者 Yuanhe Chen Lap Mou Tam Qingsong Xu 《International Journal of Extreme Manufacturing》 2026年第1期685-695,共11页
In recent years,the rising incidence of gastrointestinal(GI)cancer has triggered an urgent need for effective early intervention strategies.Traditional endoscopic techniques often cause patient discomfort,and it is di... In recent years,the rising incidence of gastrointestinal(GI)cancer has triggered an urgent need for effective early intervention strategies.Traditional endoscopic techniques often cause patient discomfort,and it is difficult to navigate deep regions of complex organ structures.This work proposes a kind of bio-inspired magnetic soft robot(BMSR)to address these challenges.The design of the BMSRs is inspired by the rolling motion of the golden wheel spider.Two six-degree-of-freedom(6-DOF)robotic arms are used,where one arm is responsible for real-time manipulation of the BMSRs,and the other is dedicated to monitoring their status.Under the actuation of an external rotating magnetic field,the BMSRs can flexibly climb on inclined surfaces at any angle,involving the inverted surface.Through the powerful output force,the BMSRs can overcome the mobility barrier induced by different human organs,including mucus,folds,and height differences of up to 8 cm.Such an exceptional mobility enables the BMSRs to deliver drugs in the targeted complex GI environment.Moreover,in combination with an endoscope,it provides real-time visual feedback for precise navigation.In vitro animal experiments validate the feasibility of BMSRs,paving a way for their usage in minimally invasive GI treatment.This work advances the potential applications of magnetic soft robots in the biomedical field. 展开更多
关键词 magnetic millirobots magnetic actuation medical robotics soft robots bio-inspired robots
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Nutrient transporters in broiler chickens:intestinal gene expression profiles,functional roles,and influencing factors
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作者 Vahideh Shay Sadr Jose A.Quinteros +1 位作者 Sonia Yun Liu Reza Barekatain 《Journal of Animal Science and Biotechnology》 2026年第2期591-612,共22页
The primary role of the gastrointestinal tract in broiler chickens is nutrient assimilation,with transporter proteins facilitating the uptake of amino acids,peptides,monosaccharides,fatty acids,and minerals across the... The primary role of the gastrointestinal tract in broiler chickens is nutrient assimilation,with transporter proteins facilitating the uptake of amino acids,peptides,monosaccharides,fatty acids,and minerals across the intestinal epithelium.Among these nutrient transporters,members of the solute carrier family are particularly important,and gene expression analyses targeting these transporters have provided informative insights into how birds adapt to diverse dietary,environmental,and physiological challenges to maintain nutrient homeostasis.These transporters are expressed either at the brush border membrane,where they facilitate the absorption of nutrients from the gut lumen into enterocytes,or at the basolateral membrane,where they mediate the transfer of nutrients from the enterocytes into the bloodstream.The expression of these transporters is influenced by a range of factors,including bird age,sex,intestinal segment,dietary substrate availability and source,as well as external stressors such as heat stress and pathogen exposure.While upregulation of transporter genes often suggests an enhanced capacity for nutrient uptake,it does not always correlate with improved growth performance,due to compensatory physiological responses and fluctuations in nutrient bioavailability.Understanding the regulation and functional dynamics of nutrient transporters presents valuable opportunities to develop targeted dietary and management strategies aimed at optimizing nutrient utilization and improving bird performance.This review summarizes current knowledge on the classification,function,and regulation of key nutrient transporters in broilers,highlights factors influencing their expression,and explores their implications for nutrition and production efficiency. 展开更多
关键词 Broiler chickens Gene expression Growth performance Nutrient homeostasis Nutrient transporters
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Boechera or not?Genomic insights and taxonomic reassessment of the misclassified Asian species B.calcarea(Brassicaceae)
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作者 Terezie Mandáková Milan Pouch +4 位作者 Petra Hloušková Dmitry A.German Pavel Trávníček Michael D.Windham Martin A.Lysak 《Plant Diversity》 2026年第1期107-116,共10页
The genus Boechera(Brassicaceae)serves as a model system for studying apomictic reproduction and ecological adaptations,with most species occurring in North America.The rare occurrence of Boechera species outside thei... The genus Boechera(Brassicaceae)serves as a model system for studying apomictic reproduction and ecological adaptations,with most species occurring in North America.The rare occurrence of Boechera species outside their typical range provides unique opportunities to investigate genome evolution in extralimital environments.One such species,B.calcarea,has been described from the Chandalaz Mountains in northeastern Asia(Russia).This study aimed to investigate the genome structure and evolutionary history of B.calcarea.However,our analyses reveal that the species does not belong to Boechera.Instead,an integrative approach combining cytogenetic,phylogenetic and repeatome analysis identified the species as a member of one of more ancestral clades in the tribe Arabideae.The diploid Parryodes calcarea(2n=16)exhibits Arabideae-specific chromosomal signatures,including multiple centromere repositionings.These findings clarify the misclassification of P.calcarea as Boechera,leaving Boechera falcata and Borodinia macrophylla as the only representatives of the Boechereae in the Old World.This study highlights the importance of an integrative approach in resolving taxonomic ambiguities and provides new insights into the diversification of the largest cruciferous tribe,the Arabideae. 展开更多
关键词 Arabideae CRUCIFERAE Chromosome structure Centromere repositioning CYTOGENETICS Phylogenetic reconstruction
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Design of a compact wide-field-of-view infrared imager based on wavefront coding
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作者 Chonghui Zhu Jiaqian Yu Jingang Cui 《Chinese Physics B》 2026年第2期383-388,共6页
Compact size,high brightness,and wide field of view(FOV)are key requirements for long-wave infrared imagers used in military surveillance or night navigation.However,to meet the imaging requirements of high resolution... Compact size,high brightness,and wide field of view(FOV)are key requirements for long-wave infrared imagers used in military surveillance or night navigation.However,to meet the imaging requirements of high resolution and wide FOV,infrared optical systems often adopt complex optical lens groups,which will increase the size and weight of the optical system.In this paper,a strategy based on wavefront coding(WFC)is proposed to design a compact wide-FOV infrared imager.A cubic phase mask is inserted into the pupil plane of the infrared imager to correct the aberration.The simulated results show that,the WFC infrared imager has good imaging quality in a wide FOV of±16°.In addition,the WFC infrared imager achieves compactness with its 40 mm×40 mm×40 mm size.A fast focal ratio of 1 combined with an entrance pupil diameter of 25 mm ensures brightness.This work is of significance for designing a compact wide-FOV infrared imager. 展开更多
关键词 optical design infrared imager wavefront coding
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Bioconversion of agro-industrial carbon wastes into biodiesel feedstocks with superior fuel properties by promising oleaginous yeasts and cultivation strategies
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作者 Amporn Malisorn Benjamas Cheirsilp +2 位作者 Asma Billateh Yasmi Louhasakul Apichat Upaichit 《Carbon Resources Conversion》 2026年第2期49-61,共13页
Oleaginous yeasts hold significant potential as biodiesel feedstocks as they accumulate high content of lipids with similar fatty acid profiles to those of plant oils.However,the commercialization of yeast lipids is l... Oleaginous yeasts hold significant potential as biodiesel feedstocks as they accumulate high content of lipids with similar fatty acid profiles to those of plant oils.However,the commercialization of yeast lipids is limited by the high cost of nutrients for yeast cultivation.This study aimed to explore the use of agro-industrial carbon wastes as low-cost nutrients and cultivation strategies for promising oleaginous yeasts.Four oleaginous yeasts were screened for their ability to grow on molasses,crude glycerol,and whey lactose.Among the yeast strains and agro-industrial wastes tested,Candida tropicalis X37 and Rhodotorula mucilaginosa G43 grew best on molasses and produced higher lipids than other strains.Both strains grew better when adding ammonium sulfate as a low-cost nitrogen source,but C.tropicalis X37 produced higher lipids when using only molasses.Through the fed-batch cultivation,C.tropicalis X37 could thrive in high molasses concentration and gave higher biomass and lipids than R.mucilaginosa G43.Scaling up in a bioreactor using an aeration rate of 1.0 air volume per liquid volume per minute further increased the production of biomass and lipids by C.tropicalis X37 up to 15.75±0.42 g/L and 6.55±0.35 g/L,respectively.The analysis of prospective fuel properties confirmed that the yeast lipids are suitable as biodiesel feedstocks.These strategies would contribute greatly to supporting green energy supply,sustainable management of wastes,and environmental protection. 展开更多
关键词 Crude glycerol Fed-batch cultivation Fuel properties MOLASSES Yeast lipids
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Interplay of Cytochrome P450 genes and flavonoid pathways in enhancing plant defense against heavy metal toxicity
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作者 Yuanpeng Fang Zehui Wang +2 位作者 Salah F.Abou-Elwafa Maha Aljabri Xin Xie 《Horticultural Plant Journal》 2026年第3期653-669,共17页
Toxic heavy metal and metalloid(THMM)contamination poses a major global challenge,threatening human health and sustainable agriculture.The crucial role of the Cytochrome P450(CYP)gene family in plant tolerance to THMM... Toxic heavy metal and metalloid(THMM)contamination poses a major global challenge,threatening human health and sustainable agriculture.The crucial role of the Cytochrome P450(CYP)gene family in plant tolerance to THMMs has been recently highlighted,but there is still a lack of comprehensive understanding,especially in relation to metabolites.This study delved into the identification of CYP genes that are linked to the tolerance mechanisms of plants in response to heavy metal stress.The findings highlight the significant metabolic pathways that contribute to this resilience,using rice and Arabidopsis as exemplars.THMM exposure changed CYP gene expression in plants,and THMM antidotes mitigated its downregulation and that of flavonoid biosynthesis genes.CYP genes involved in THMM responses were predominantly enriched in the pathways associated with flavonoid synthesis,indicating functional adaptations to distinct stresses.Notably,anthocyanin(Ant)accumulation,a type of flavonoid,affected the uptake of various heavy metals in Brassica rapa,with flavonoid biosynthesis-associated genes correlating with Cd or As tolerance and Ant content.These findings highlight the critical importance of flavonoid metabolism and the intricate network of biosynthesis genes in bolstering plant resilience against heavy metal stress.This enhanced understanding paves the way for significant advancements in phytoremediation technologies,offering innovative solutions for soil and water decontamination. 展开更多
关键词 Heavy metals Cytochrome P450 Flavonoid biosynthesis ANTHOCYANIN Plant tolerance
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Improved Performance and Compost Biodegradation of PLA/PBAT Blend and PLA/PBAT Compatibilized Blends with Algae as a Reinforcer
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作者 John Letwaba Sudhakar Muniyasamy +1 位作者 Nagarethinam Rakku Lucey Mavhungu 《Journal of Renewable Materials》 2026年第2期106-125,共20页
Melt blending of biodegradable polyesters such as poly(lactic acid)(PLA)and poly(butylene adipate co-terephthalate)(PBAT)with a compatibilizer and natural filler offers a chance to develop biodegradable biocomposites ... Melt blending of biodegradable polyesters such as poly(lactic acid)(PLA)and poly(butylene adipate co-terephthalate)(PBAT)with a compatibilizer and natural filler offers a chance to develop biodegradable biocomposites with improved performance.In this study,we examined how PLA/PBAT blends behave during ultimate biodegradation(mineralization),both with and without compatibilizer and algae as a reinforcement,under controlled composting conditions using carbon dioxide(CO_(2))respirometry techniques.Throughout the biodegradation process,the disintegration behaviour,thermal,chemical,and morphological properties of test samples before and after biodegradation were analyzed using FTIR,TGA,DSC,and SEM techniques.The results from CO_(2)biodegradation showed that PLA/PBAT blend exhibits a higher rate of biodegradation compared to neat PLA and PBAT.The addition of algae to a compatibilized PLA/PBAT blend showed an enhanced biodegradation rate due to hydrolytic cleavage and microbial assimilation.This was further supported by the disintegration test,where algae-reinforced composites showed fragmentation within 30 days.FTIR,TGA and SEM analysis revealed the structural changes that occurred during biodegradation,highlighting the role of algae in affecting the thermal stability and surface morphology.After the compost biodegradation step,eco-toxicity seed germination was conducted on the test samples.Plant seed germination test results confirmed that all test samples achieved maximumgermination.This indicates there were no toxic residues,suggesting that the degraded materials are environmentally safe.Overall,this study contributes to the understanding of biodegradation mechanisms and the ecological impact of bio-based polymer composites as eco-friendly materials and products. 展开更多
关键词 PLA PBAT COMPATIBILIZER ALGAE BIO-COMPOSITES mechanical properties thermal properties
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BRST formalism of f(R)gravity
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作者 Ichiro Oda 《Communications in Theoretical Physics》 2026年第2期108-120,共13页
We perform the manifestly covariant quantization of f(R)gravity in the de Donder gauge condition(or harmonic gauge condition)for general coordinate invariance.We explicitly calculate various equal-time commutation rel... We perform the manifestly covariant quantization of f(R)gravity in the de Donder gauge condition(or harmonic gauge condition)for general coordinate invariance.We explicitly calculate various equal-time commutation relations(ETCRs),in particular the ETCR between the metric and its time derivative,and show that it has a nonvanishing and nontrivial expression,whose situation should be contrasted to the previous result in higher-derivative or quadratic gravity where the ETCR was found to be identically vanishing.We also clarify global symmetries,the physical content of f(R)gravity,and clearly show that this theory is manifestly unitary and has a massive scalar and massless graviton as physical modes. 展开更多
关键词 BRST formalism f(R)gravity covariant quantization
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Predicting the potential habitat suitability of invasive Chromolaena odorata and Tithonia differsifolia in Nigeria's urban ecosystems using MaxEnt
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作者 Abdulfatai B.Rufai Olusanya A.Olatunji +5 位作者 Gideon O.Okunlola Saheed O.Adebisi Idris O.Raimi Emmanuel T.Komolafe Emmanuel C.Chukwuma Mahboob A.Jimoh 《Ecological Frontiers》 2026年第1期197-209,共13页
Rapid colonization by invasive plants threatened local biodiversity worldwide;however,their distributional hotspots and future habitat shifts remain poorly understood in developing nations such as Nigeria.Using MaxEnt... Rapid colonization by invasive plants threatened local biodiversity worldwide;however,their distributional hotspots and future habitat shifts remain poorly understood in developing nations such as Nigeria.Using MaxEnt model,we investigated present and future habitat suitability for two aggressive invaders,C.odorata and T.diversifolia,across Nigeria's urban landscapes.We used a dataset consisting of 327 and 108 occurrence points for C.odorata and T.diversifolia,respectively,along with twenty-three(23)environmental variables to identify occurrence and areas of concern under current climatic fluctuations.The results revealed that the model performed strongly(AUC>0.85)and identified precipitation seasonality as the dominant predictor for both species.The finding indicates that precipitation seasonality of≤59 CV,isothermality of≥57%and precipitation of wettest month of≥170 mm enhance niche occupancy of C.odorata,while precipitation seasonality of 62-70 CV,precipitation of wettest quarter and maximum temperature of warmest month of≥450 mm and 35℃,respectively enhance that of T.differsifolia.Current predictions place C.odorata primarily along the southern coast,while T.diversifolia is most suitable in the southwest and extends into the northcentral.Future suitable area for C.odorata will slightly expand by 2050 and 2070,encroaching into southeastern and some central states.In contrast,T.diversifolia contracts under CNRM-CM5 but shows a modest expansion under GFDL-CM3.These projections indicate that climate change may reinforce the dominance of C.odorata in southern Nigeria,whereas T.differsifolia may exhibit divergent trajectories from southern to certain northern states in the future. 展开更多
关键词 Invasive species T.Differsifolia C.odorata MAXENT Bioclimatic Topographic Precipitation SEASONALITY
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Seismotectonic analysis and characterization of seismic source zones in Cameroon,Central Africa
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作者 Eddy Ferdinand Mbossi Etoundi Delair Dieudonné Ndibi +5 位作者 Jean Marcel Abate Essi Pauline Nguet Wokwenmendam Nfomou Ntepe Mustapha Meghraoui Bekoa Ateba Tabod Charles Tabod 《Earthquake Science》 2026年第2期156-189,共34页
A compilation of databases from Cameroon and neighbouring countries,including seismicity,stress tensor distribution,gravity,magnetic,topography,lithosphere structure and geological data,is used to define its seismotec... A compilation of databases from Cameroon and neighbouring countries,including seismicity,stress tensor distribution,gravity,magnetic,topography,lithosphere structure and geological data,is used to define its seismotectonic zonation.Based on the quality and quantity of available data,a seismotectonic map was drawn up through the characterization of subunits of concentrations of earthquake foci and,large neotectonic and structural domains.To prepare this map,a homogeneous earthquake catalogue was compiled from the literature and international data centers dated from 1852 up to 2023.Another point of study was to establish links between seismicity and deformation zones.Many faults and/or structures were identified as possibly active,although some of them are not always associated with seismicity.A seismotectonic model for Cameroon was then built from a classification of faults,neotectonic and seismogenic regions.This structured and highly data-driven approach has been developed specifically for the definition of source zones where seismicity is not well known.The results of the seismotectonic analysis allowed characterizing seventeen seismotectonic source zones in Cameroon.Five source zones are defined in the Mount Cameroon region which is the greatest seismicity activity in the study area.The crustal thickness map of Cameroon revealed a thinned transitional zone interspersed between the thickened Congo Shield and thin Pan-African belt favourable for the development of megastructures such as Central Cameroon shear zone and Kribi-Campo shear zone.This region represents the second highest seismicity zone and contains five source zones. 展开更多
关键词 Cameroon SEISMICITY catalogue of seismicity FAULTS seismotectonic model ZONATION
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Pressure calibrations of high-pressure large-volume presses at HPSTAR
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作者 Yongjiang Xu Peiyan Wu +17 位作者 Sheng Shang Xue Wang Taihang Li Shuchang Gao Shijie Lv Hang Cheng Qianzhi Xu Shang Lei Jiajia Feng Lei Zhao Wim van Westrenen Takayuki Ishii Bin Chen Lei Su Yang Ding Wenge Yang Ho-Kwang Mao Yanhao Lin 《Matter and Radiation at Extremes》 2026年第1期111-130,共20页
Large-volume presses(LVPs)are widely utilized in diverse research fields—including high-pressure physics,chemistry,materials science,and Earth and planetary sciences—to investigate the physical and chemical properti... Large-volume presses(LVPs)are widely utilized in diverse research fields—including high-pressure physics,chemistry,materials science,and Earth and planetary sciences—to investigate the physical and chemical properties of materials under extreme high-pressure and hightemperature conditions.A prerequisite for achieving reproducible property measurements is the determination and control of pressure within experimental setups.However,the lack of precise pressure calibration in LVPs hinders the broader application of such devices in ultrahigh-pressure studies.This study employs a suite of standard phase transition-based pressure markers—comprising metallic conductors,semiconductors,and minerals—through both in situ and ex situ identification approaches,to establish pressure calibration curves ranging from 0.4 to>30 GPa for various types of LVP installed at the Center for High Pressure Science and Technology Advanced Research(HPSTAR),Beijing,including piston–cylinder,cubic,and multi-anvil presses.The results provide a unified and traceable pressure reference for highpressure experiments conducted at HPSTAR,while also offering technical guidance and calibration standards for other researchers utilizing similar LVP systems,thereby enabling more consistent comparison between different laboratories.This work facilitates the advancement of LVP research toward broader applications in higher-pressure regimes. 展开更多
关键词 CHEMISTRY earth planetary sciences pressure calibration high pressure physics materials science investigate physical chemical properties materials determination control pressure
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Subtle Micro-Tremor Fusion:A Cross-Modal AI Framework for Early Detection of Parkinson’s Disease from Voice and Handwriting Dynamics
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作者 H.Ahmed Naglaa E.Ghannam +1 位作者 H.Mancy Esraa A.Mahareek 《Computer Modeling in Engineering & Sciences》 2026年第2期1070-1099,共30页
Parkinson’s disease remains a major clinical issue in terms of early detection,especially during its prodromal stage when symptoms are not evident or not distinct.To address this problem,we proposed a new deep learni... Parkinson’s disease remains a major clinical issue in terms of early detection,especially during its prodromal stage when symptoms are not evident or not distinct.To address this problem,we proposed a new deep learning 2-based approach for detecting Parkinson’s disease before any of the overt symptoms develop during their prodromal stage.We used 5 publicly accessible datasets,including UCI Parkinson’s Voice,Spiral Drawings,PaHaW,NewHandPD,and PPMI,and implemented a dual stream CNN–BiLSTM architecture with Fisher-weighted feature merging and SHAP-based explanation.The findings reveal that the model’s performance was superior and achieved 98.2%,a F1-score of 0.981,and AUC of 0.991 on the UCI Voice dataset.The model’s performance on the remaining datasets was also comparable,with up to a 2–7 percent betterment in accuracy compared to existing strong models such as CNN–RNN–MLP,ILN–GNet,and CASENet.Across the evidence,the findings back the diagnostic promise of micro-tremor assessment and demonstrate that combining temporal and spatial features with a scatter-based segment for a multi-modal approach can be an effective and scalable platform for an“early,”interpretable PD screening system. 展开更多
关键词 Early Parkinson diagnosis explainable AI(XAI) feature-level fusion handwriting analysis microtremor detection multimodal fusion Parkinson’s disease prodromal detection voice signal processing
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