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1Assessing Soil Available Potassium by Cation Exchange Membrane and Conventional Chemical Extractions 被引量:3
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作者 LIUZHAOHUI J.SCHOENAU 《Pedosphere》 SCIE CAS CSCD 1999年第1期91-96,共6页
Four testing methods using canon exchange membrane (CEM), ammonium acetate, ASI (0.25 mol L-1 NaHCO3+0.01 mol L-1 EDTA +0.01 mol L-1 NH4P) and 1.0 mol L-1 boiling nitric acid, respectively, were used to evaluate soil ... Four testing methods using canon exchange membrane (CEM), ammonium acetate, ASI (0.25 mol L-1 NaHCO3+0.01 mol L-1 EDTA +0.01 mol L-1 NH4P) and 1.0 mol L-1 boiling nitric acid, respectively, were used to evaluate soil available K. The soil K tested by CEM was significantly correlated with that by the other (conventional) methods (r2=0.43**~0.95***). The soil K tested by CEM saturated with NH4HCO3 (15 min extraction) was most closely correlated with that by the other methods (2 =0. 60***~0.95***). Potassium availability, as predicted by soil test, was comparable to actual K uptake by canola and wheat grown on the soils in growth chamber. Regression analyses showed that plant K uptake was more closely correlated with K extracted by CEM (r2=0.56***~0.81***) than that by the conventional methods (r2=0.46***~;0.81***), most closely correlsted with that by NH4HCO3-saturated CEM for 15 min (r2=0.81***), and worst correlated with that by HNO3 (r2=0.45**~0.72***). 展开更多
关键词 canon exchange resin membrane conventional chemical extractions soil available potassium
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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins 被引量:3
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作者 Antonio Pizzi Marie-Pierre Laborie Zeki Candan 《Journal of Renewable Materials》 EI CAS 2024年第3期397-425,共29页
Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly ... Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses. 展开更多
关键词 TANNINS FLAVONOIDS SOURCES extraction methods analysis methods
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Using a pre-kicker to ensure safe extractions from the HEPS storage ring 被引量:1
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作者 Zhe Duan Jin-Hui Chen +3 位作者 Hua Shi Guang-Yi Tang Lei Wang Yu-Wen Wu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第12期26-36,共11页
The High Energy Photon Source(HEPS)is a 6 GeV diffraction-limited storage ring light source under construction.The swap-out injection is adopted with the depleted bunch recycled via high-energy accumulation in the boo... The High Energy Photon Source(HEPS)is a 6 GeV diffraction-limited storage ring light source under construction.The swap-out injection is adopted with the depleted bunch recycled via high-energy accumulation in the booster.The extremely high beam energy density of the bunches with an ultra-low emittance(about 30 pm horizontally and 3 pm vertically)and high bunch charges(from 1.33 to 14.4 nC)extracted from the storage ring could cause hazardous damage to the extraction Lambertson magnet in case of extraction kicker failure.To this end,we proposed the use of a pre-kicker to spoil the bunches prior to extraction,significantly reducing the maximum beam energy density down to within a safe region while still maintaining highly efficient extractions.The main parameters of the pre-kicker are simulated and discussed. 展开更多
关键词 Pre-kicker The high energy photon source Intense electron beam Diffraction-limited storage ring Extraction Lambertson magnet
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Discriminant Analysis in the Study of Alzheimer's Disease Using Feature Extractions and Support Vector Machines in Positron Emission Tomography with ^(18)F-FDG
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作者 苏赛赛 陈克伟 黄秋 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第5期555-560,共6页
With more successful applications of advanced medical imaging technologies in clinical diagnosis, various analytic discriminant approaches, by seeking the imaging based characteristics of a given disease to achieve au... With more successful applications of advanced medical imaging technologies in clinical diagnosis, various analytic discriminant approaches, by seeking the imaging based characteristics of a given disease to achieve automatic diagnosis, gain greater attention in the medical community. However the existing computer-aided discriminant procedures for Alzheimer's disease (AD) are yet to be improved for better identifying patients with mild cognitive impairment (MCI) from those with AD and those who are cognitively normal. In this work we present a computer assisted diagnosis approach by first statistically extracting characteristics from whole brain 2-deoxy-2-(lSF)fluoro-D-glucose positron emission tomography (lSF-FDG PET) images, and then using support vector machines for classification. Evaluations of the proposed procedure with patient data exhibit satisfactory accuracies in distinguishing AD from its early stage MCI, and normal controls. 展开更多
关键词 Alzheimer’s disease feature extraction CLASSIFICATION mild cognitive impairment(MCI)
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Effects of Mandibular Extractions with Clear Aligners:A Finite Element Analysis
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作者 FENG Qiping CHU Fengting +1 位作者 CHEN Rongjing PAN Xiaogang 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第3期377-382,共6页
This study was aimed at analysing the mechanical characteristics of different mandibular extraction modes using a clear aligner.Three experimental schemes of different extraction patterns were designed to treat mandib... This study was aimed at analysing the mechanical characteristics of different mandibular extraction modes using a clear aligner.Three experimental schemes of different extraction patterns were designed to treat mandibular crowding,including extraction of one mandibular central incisor,bilateral first premolars,and bilateral second premolars.The stress distribution during the space closing was analysed using the finite element method.When a central incisor was extracted,a significant retraction force was found in the anterior region,in line with the design expectation.The posterior teeth,which were designed to move mesially,acted as anchorage for anterior retraction,and were subjected to a mesial force.The anterior teeth were retracted when the bilateral first premolars were extracted.The lateral incisors and canines were subjected to a significant distal force and moment,while the central incisors and canines were subjected to lingual forces and moments.Additionally,the canines were subjected to a non-designated intruding force.The molars were designed to move mesially when the bilateral second premolars were extracted.All molars were subjected to a significant mesial force,while the lingual force on the front teeth was slight.The bilateral second molars were subjected to non-design mesial moment and extrusive force.The bilateral first molars were subjected to a non-designated mesial moment,and the bilateral first premolars on both sides were subjected to non-designated intrusive force and distal moment.When one incisor was extracted,attachments on the anterior teeth had a controlling effect on the tooth axis,but the anterior teeth still tended to tilt.When the bilateral first premolars were extracted,the anterior teeth showed a tendency for lingual inclination.The risk of distal inclination of the canines and lingual inclination of the central incisor increased.When the bilateral second premolars were extracted and the posterior teeth were designed to move mesially,the teeth on both sides of the extraction sites showed an obvious bowing effect. 展开更多
关键词 clear aligner mandibular incisor extraction finite element analysis
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Use of Flexible Periotomes and Conventional Periotomes in Atraumatic Extractions: A Comparative Study
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作者 Zoya Rafiq Kolari Vinayakrishna Joyce P. Sequeira 《Open Journal of Stomatology》 CAS 2023年第4期134-142,共9页
The aim of this study was to compare the efficiency of flexible periotomes versus non-flexible conventional periotomes in atraumatic dental extractions of similar teeth. The study also aimed to evaluate the wound heal... The aim of this study was to compare the efficiency of flexible periotomes versus non-flexible conventional periotomes in atraumatic dental extractions of similar teeth. The study also aimed to evaluate the wound healing, duration of the procedure, and level of gingival laceration associated with the use of these two instruments. The study was a randomized controlled clinical trial involving 26 patients requiring nonsurgical tooth extractions bilaterally. The subjects were randomized into two groups: the study group, where flexible periotomes were used to break the periodontal ligament, and the control group, where conventional periotomes were used. A total of 52 extractions were performed, either for orthodontic or implant placement purposes. After the extractions, the researchers evaluated the level of gingival laceration, duration of the procedure, and wound healing on postoperative days 1 and 7. Any complications that arose were also noted. The study group (flexible periotome) and control group (conventional periotome) were compared, and the results showed that the flexible periotomes required a shorter duration of time (around 4 minutes) compared to conventional periotomes (7 minutes). Additionally, gingival lacerations were found to be less severe in the study group. In conclusion, the use of flexible periotomes was found to be more efficient in atraumatic dental extractions compared to conventional periotomes. This study highlights the importance of using newer technology to perform atraumatic extractions, particularly in the era of implantology where there is an increased demand for such procedures. 展开更多
关键词 Randomized Clinical Trial Periotome Flexible Periotome Atraumatic Extraction
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Fetal Instrumental Extractions at the Maternity Section of the Dakar Nabil Choucair Health Centre (Senegal) in 2017: Epidemio-Clinical Aspects, Indications and Prognosis
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作者 Omar Gassama Babacar Biaye +6 位作者 Boura Taoufiki Ndeye Astou Faye Djibril Diallo Aminata Niass Abdou Ndiaye Alassane Diouf Jean Charles Moreau 《Open Journal of Obstetrics and Gynecology》 2020年第3期390-399,共10页
Introduction:?An instrumental extraction is performed in order to shorten the phase of expulsion of the fetus outside the maternal pelvic pathway, when there is a suspected fetal state or a defect in progression of th... Introduction:?An instrumental extraction is performed in order to shorten the phase of expulsion of the fetus outside the maternal pelvic pathway, when there is a suspected fetal state or a defect in progression of the fetal mobile. It can be responsible for immediate or late maternal complications, which are not specific because they can occur after a normal delivery. The objectives of this work are to describe the epidemiological-clinical and prognosis aspects of deliveries assisted by instrumental extractions in a reference maternity unit in Dakar.?Materials and Methods:?This was a retrospective, descriptive and analytical study between January 1, 2017 and December 31, 2017, a period of 12 months at the maternity ward of the Nabil Choucair Health Center. The collection was carried out using the survey form completed on the basis of the analysis of the files, the delivery register and the anaesthesia register of the operating room. The parameters studied were about socio-demographic?characteristics, indications and prognosis. The data entry was carried out using the Sphinx version 5 software and the data analysis using the Epi info version?3.5?software. Results:?During the period of our study, we collected 94 instrumental?extractions. The frequency of instrumental extractions was?1.7%. The average age of the patients was 25 years with extremes of 16 to 43 years old. The average parity was 1 with extremes 1 to 6. Among parturient women, 12?patients (12.8%) had a history of suction cup, two (2.1%) had received forceps and three (3.2%) had a cesarean section. The average gestational age was 39 Weeks of Amenorrhea (WA), the average uterine?height was 32?cm, fetal heart sounds were normal in 98% parturient’ cases. The vaginal?touch had found a fully dilated cervix, a rupture of the amniotic sac with clear amniotic?fluid in 98% of parturient women and a fetus with an anterior left iliac occipito topin 69.4% of cases. The pelvis was clinically normal in all parturient women. The indications were dominated by maternal fatigue (65.9%). The spatula was the?most commonly used instrument (82.7%). Episiotomy was performed in 97.3%?of cases. The average weight of the newborn was 3058 grams and an Apgar score of 8/10 was noted in 96% of newborns. We noted 3?cases of maternal complications with perineal tear type (3.2%) and 1 case of perineal tear associated with postpartum hemorrhage (1.06%). The neonatal prognosis was dominated by 2 caput succedaneum cases (2.1%). Newborns were alive and well in 97.8%. We noted 2 cases of death, i.e. 2.1% in?unsolved circumstances. All the mothers were alive and well at (100%). Conclusion:?Instrumental extractions must be integrated into our structures?to significantly reduce the number of abusive cesarean sections. The perfect mastery of extraction techniques and indications makes?it possible to?reduce fetal suffering while avoiding the morbidity associated with instrumental?extractions. 展开更多
关键词 INSTRUMENTAL Extraction Suction Cup Spoonbill FORCEPS
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A Comparative Study of Soluble Protein Extractions of Populus deltoides × ( Trichocarpa × Deltoides) for 2-DE
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作者 Joke Dupae Ann Cuypers +4 位作者 Jean-Paul Noben Jana Boulet Nele Weyens Karen Verstraelen Jaco Vangronsveld 《Journal of Life Sciences》 2012年第9期970-979,共10页
Background: The disclosure of the poplar genome strengthens its position as well-established model organism. Populus has been subject of several proteome studies, but up to date no comparative study was performed on ... Background: The disclosure of the poplar genome strengthens its position as well-established model organism. Populus has been subject of several proteome studies, but up to date no comparative study was performed on the extraction method of soluble proteins for this species. The extraction is the most critical step in two-dimensional gel electrophoresis and each extraction method has its advantages, disadvantages and limitations. Therefore protein extraction methods should be optimized for each tissue before starting an experimental setup. In prospect of future DIGE (Differential Gel electrophoresis) experiments for the investigation of the effects of cadmium and inoculation with plant growth promoting bacteria at the proteome level, the aim of this study was to optimize an extraction method for soluble proteins of poplar leaves and roots. Results: The acetone-phenol extraction method was found to be the most suited, rendering a high spot number and low background interference. During further optimization, several critical steps in the extraction method were revealed. Conclusion: Aiming to optimize the extraction of soluble leaf and root proteins of Populus deltoides × (trichocarpa× deltoides) compatible with DIGE analysis, a protocol rendering high reproducibility, low background interference and a high spot number was established, however no novel insights were acquired. 展开更多
关键词 PROTEOMICS two-dimensional gel electrophoresis soluble proteins protein extraction Populus.
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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 Starch particle Physicochemical properties Starch function Resistant starch Starch extraction
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Artificial intelligence-enabled high-precision colony extraction and isolation system
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作者 ZHAO Xu-feng JIA Zhi-qiang +5 位作者 CHEN Wei-xue HU Peng-tao SU Xin-ran LI Jun-lin GE Ming-feng DONG Wen-fei 《中国光学(中英文)》 北大核心 2026年第1期190-204,共15页
Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and... Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel. 展开更多
关键词 artificial intelligence colony extraction and isolation large-field imaging AUTOMATION
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Coordination-driven in-situ reduction and extraction of neptunium
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作者 Huaixin Hao Shuyun Zhang +7 位作者 Xue Dong Qilong Tang Yuxiao Guo Yaoyang Liu Jing Chen Jing Su Zhipeng Wang Chao Xu 《Science China Chemistry》 2026年第2期777-783,共7页
The recycling of neptunium(Np)from nuclear wastes is crucial for the sustainable development of nuclear energy,yet it is still a challenging task owing to the complexity of Np chemistry.Precise control of oxidation st... The recycling of neptunium(Np)from nuclear wastes is crucial for the sustainable development of nuclear energy,yet it is still a challenging task owing to the complexity of Np chemistry.Precise control of oxidation state is highly desirable for the effective recovery of Np.In this study,we report an innovative strategy for Np recovery through in-situ coordination and reduction of Np(Ⅴ)in a biphasic extraction system.By leveraging the synergistic effects of coordination by a P=O donating ligand(trialkyl phosphine oxide,TRPO)and reduction by hydroquinone(HQ)in the organic phase,efficient Np(Ⅴ)-to-Np(Ⅳ)conversion and high distribution ratio(D)of Np were achieved in a single extraction contact.The reduction mechanism of Np was elucidated through spectroscopic and theoretical analyses.This work enriches the redox chemistry of Np and provides a novel pathway for Np recovery in advanced nuclear fuel cycles. 展开更多
关键词 NEPTUNIUM COORDINATION REDUCTION EXTRACTION
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Comparative Analysis of the Impact of Different Ecotypes on In Vitro Anti-Inflammatory Activity of Ethanolic Extracts of Moringa oleifera Leaves
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作者 Mario D’Ambrosio Elisabetta Bigagli +4 位作者 Lorenzo Cinci Cecilia Brunetti Edgardo Giordani Francesco Ferrini Cristina Luceri 《Phyton-International Journal of Experimental Botany》 2026年第1期23-33,共11页
Moringa oleifera(MO)is traditionally used to mitigate inflammatory-mediated disorders;however,the influence of ecotypic variation on its anti-inflammatory activity remains poorly understood.In this study,we compared t... Moringa oleifera(MO)is traditionally used to mitigate inflammatory-mediated disorders;however,the influence of ecotypic variation on its anti-inflammatory activity remains poorly understood.In this study,we compared the phytochemical composition and anti-inflammatory activity of ethanolic extracts obtained from fresh and dried leaves of four MO ecotypes(India,Paraguay,Mozambique,and Pakistan),all grown under the same outdoor conditions,as well as two commercial powders(Just Moringa and WISSA),using LPS-stimulated RAW 264.7 macrophages.Extracts from fresh leaves were 19-43%more cytotoxic than those from dried leaves,depending on the ecotype,likely due to higher cyanogenic glycoside content.Extracts from the India and Paraguay ecotypes,characterized by high levels of quercetin derivatives and caffeic acids,as well as Just Moringa,enriched in kaempferol derivatives,significantly inhibited LPS-induced nitric oxide(NO)production(p<0.05).Just Moringa and Paraguay extracts also reduced iNOS gene expression(p<0.05 and p<0.01,respectively),whereas only the Paraguay extract decreased iNOS protein levels(p<0.05).In contrast,quercetin-3-O-glucoside and rutin showed significant effects only at concentrations approximately 100-fold higher than those present in the extracts,indicating that the phytocomplex displays greater bioactivity than individual compounds.Overall,these results demonstrate that ecotypic variation strongly affects the polyphenolic composition and anti-inflammatory properties of MO leaves,highlighting the importance of reporting both origin and phytochemical composition in MO-based products. 展开更多
关键词 Moringa oleifera ECOTYPE INFLAMMATION plant extract POLYPHENOLS
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Engineering a Bilayered Scaffold as a Potential Cardiac Patch:From Scaffold Design to In Vitro Assessment
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作者 Adile Yuruk Ayhan Duzler +1 位作者 Sevil Dincer Isoglu Ismail Alper Isoglu 《Journal of Bionic Engineering》 2026年第1期394-415,共22页
In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electros... In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electrospun Poly(lactic-co-glycolic acid)/Gelatin(PLGA/Gel)membrane incorporated with Vascular Endothelial Growth Fac-tor(VEGF)and hawthorn extract.Functionally,the DP supplies native Extracellular Matrix(ECM)components and mechanical support,while PANINPs provide conductivity.The electrospun PLGA/Gel layer mimics fibrous ECM.It incorporates bioactives,with VEGF promoting pro-angiogenic stimulation and hawthorn extract enhanc-ing anticoagulant activity,as well as increasing surface hydrophilicity.The tissue adhesive ensures the interfacial integrity between the two layers.Decellularization efficiency was confirmed histologically using 4',6-diamidino-2-phenylindole(DAPI)and Hematoxylin-Eosin(H&E)staining.The DP exhibited a DNA content of 115.9±47.8 ng/mg DNA,compared to 982.88±395.42 ng/mg in Native Pericardium(NP).The PANINPs had an average par-ticle size of 104.94±13.7 nm.The conductivity of PANINPs-coated decellularized pericardium was measured to be 9.093±8.6×10-4 S/cm using the four-point probe method.PLGA/Gel membranes containing hawthorn extract(1%,5%,10%,and 15%w/v)and VEGF(0.1μg/mL,0.5μg/mL,and 1μg/mL)were fabricated by electrospinning,result-ing in fiber diameters between 850 and 1200 nm and pore sizes between 14 and 20μm.The anticoagulant efficiency of the membranes containing hawthorn extract reached 430 s in the Activated Partial Thromboplastin Time Assay(aPTT).Mechanical testing revealed a tensile strength of 22.70±6.33 MPa,an elongation of 53.58±10.63%,and Young's modulus of 0.67±0.10 MPa.The scaffold also exhibited over 91%cell viability and excellent cardiomyo-cyte adhesion.The hemolysis ratio was determined to be 0.421±0.191%,which confirms its blood compatibility.Our results indicate that the proposed bilayered scaffold can be a promising candidate for cardiac patch applications. 展开更多
关键词 Cardiac patch Bilayered scaffold DECELLULARIZATION ELECTROSPINNING Hawthorn extract VEGF
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Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications
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作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 2026年第5期15-30,共16页
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis... The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness. 展开更多
关键词 Defect cleavage COF nanofibers Flexibility AEROGELS Uranium extraction
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Biostimulatory Influence of Commercial Seaweed Extract on Seed Emergence,Seedling Growth,and Vigor of Winter Rice
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作者 Zakia Akter Sumona Akter Jannat +5 位作者 Sheikh Md.Shibly Afroza Sultana Amdadul Hoque Amran Joairia Hossain Faria Sabina Yeasmin Md.Parvez Anwar 《Phyton-International Journal of Experimental Botany》 2026年第1期327-344,共18页
Seaweed extract contains plant growth regulators and bio-stimulants that enhance plant growth and development.In Bangladesh,winter rice(Boro rice)in the nursery bed often shows poor seed emergence and weak seedling gr... Seaweed extract contains plant growth regulators and bio-stimulants that enhance plant growth and development.In Bangladesh,winter rice(Boro rice)in the nursery bed often shows poor seed emergence and weak seedling growth due to low temperature.This problem can be addressed by using seaweed extract as a seed priming agent and bio-stimulant.The objective of this study was to evaluate the effectiveness of seaweed extract(Crop Plus)on seed emergence,seedling growth,and vigor of winter rice in the nursery.Two experiments were conducted at Bangladesh Agricultural University using BRRI dhan89.The laboratory experiment consisted of 17 treatments combining three concentrations of Crop Plus(5000,10,000 and 15,000 ppm)and four priming durations(6,12,18,and 24 h),along with hydro-priming and a no priming as control.Seed priming with 15,000 ppm for 24 h produced the highest germination percentage and superior seedling growth traits.The nursery bed experiment comprised 11 treatments combining two doses(1 mL m^(−2)and 2 mL m^(−2))of Crop Plus and five different foliar application schedules,along with a control.All treatments outperformed the control,with the best results from Crop Plus@2 mL m^(−2)applied at 20 and 30 days after sowing(DAS).Overall,the treatment involving seed priming with 15,000 ppm seaweed extract for 24 h,followed by nursery application at 2 mL m^(−2)at 20 and 30 DAS,resulted in higher germination and improved early growth of winter rice.However,further validation across multiple locations,seasons,and rice cultivars is recommended. 展开更多
关键词 Seaweed extract seed invigoration foliar feeding GERMINATION seedling vigor PADDY
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Straightforward and versatile construction of phenanthroline-derived diamide ligands for f-block element extraction
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作者 Dong Fang Xiaofan Yang +1 位作者 Fengxin Gao Chengliang Xiao 《Chinese Chemical Letters》 2026年第1期602-605,共4页
As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive stu... As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive study.In this work,we first report a convenient synthetic method for the construction of DAPhen using Friedländer reaction by two facile steps(vs.previous 12 steps).A variety of DAPhen ligands are readily available,especially unsymmetrical ones,which give us a platform to systematically study the substituent effect on f-block elements extraction performance.The performance of unsymmetrical extractants is experimentally confirmed to falls between that of their corresponding symmetrical extractants by extracting UO_(2)^(2+) as the representative f-block element.This work provides a direct and versatile method to synthesize symmetrical and unsymmetrical DAPhen,which paves way for the investigations on their coordination properties with metal ions and other applications. 展开更多
关键词 Phenanthroline diamide ligand Friedlander reaction UNSYMMETRICAL SYMMETRICAL Solvent extraction
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Cutting-edge aminated conjugated microporous poly(aniline)s enabled high-performance membrane for seawater uranium extraction
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作者 Xiaoxia Ye Bingqing Huang +7 位作者 Xueying Chen Yaping Wang Zhihong Zheng Yifan Liu Yuancai Lv Chunxiang Lin Jian Huang Jie Chen 《Green Energy & Environment》 2026年第1期181-194,共14页
The extraction of uranium from seawater via membrane adsorption is a promising strategy for ensuring a long-term supply of uranium and the sustainability of nuclear energy.However,this approach has been hindered by th... The extraction of uranium from seawater via membrane adsorption is a promising strategy for ensuring a long-term supply of uranium and the sustainability of nuclear energy.However,this approach has been hindered by the longstanding challenge of identifying sustainable membrane materials.In response,we propose a prototypal hybridization strategy to design a novel series of aminated conjugated microporous polymer(CMPN)@collagen fiber membrane(COLM).These sustainable and low-cost membrane materials allow a rapid and high-affinity kinetic to capture 90%of the uranium in just 30 min from 50 ppm with a high selectivity of Kd>105 mL·g^(−1).They also afford a robustly reusable adsorption capacity as high as 345 mg·g^(−1)that could harvest 1.61 mg·g^(−1)of uranium in a short 7-day real marine engineering in Fujian Province,even though suffered from very low uranium concentration of 3.29μg·L^(−1)and tough influence of salts such as 10.77 g·L^(−1)of Na^(+),1.75μg·L^(−1)of VO_(3)^(−)etc.in the rough seas.The structural evidence from both experimental and theoretical studies confirmed the formation of favorable chelating motifs from the amino group on CMPN-COLM,and the intensification by the synergistic effect from the size-sieving action of CMPN and the capillary inflow effect of COLM. 展开更多
关键词 Conjugated microporous polymer Collagen fiber MEMBRANE Seawater Uranium extraction
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Enhanced Multi-Scale Feature Extraction Lightweight Network for Remote Sensing Object Detection
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作者 Xiang Luo Yuxuan Peng +2 位作者 Renghong Xie Peng Li Yuwen Qian 《Computers, Materials & Continua》 2026年第3期2097-2118,共22页
Deep learning has made significant progress in the field of oriented object detection for remote sensing images.However,existing methods still face challenges when dealing with difficult tasks such as multi-scale targ... Deep learning has made significant progress in the field of oriented object detection for remote sensing images.However,existing methods still face challenges when dealing with difficult tasks such as multi-scale targets,complex backgrounds,and small objects in remote sensing.Maintaining model lightweight to address resource constraints in remote sensing scenarios while improving task completion for remote sensing tasks remains a research hotspot.Therefore,we propose an enhanced multi-scale feature extraction lightweight network EM-YOLO based on the YOLOv8s architecture,specifically optimized for the characteristics of large target scale variations,diverse orientations,and numerous small objects in remote sensing images.Our innovations lie in two main aspects:First,a dynamic snake convolution(DSC)is introduced into the backbone network to enhance the model’s feature extraction capability for oriented targets.Second,an innovative focusing-diffusion module is designed in the feature fusion neck to effectively integrate multi-scale feature information.Finally,we introduce Layer-Adaptive Sparsity for magnitude-based Pruning(LASP)method to perform lightweight network pruning to better complete tasks in resource-constrained scenarios.Experimental results on the lightweight platform Orin demonstrate that the proposed method significantly outperforms the original YOLOv8s model in oriented remote sensing object detection tasks,and achieves comparable or superior performance to state-of-the-art methods on three authoritative remote sensing datasets(DOTA v1.0,DOTA v1.5,and HRSC2016). 展开更多
关键词 Deep learning object detection feature extraction feature fusion remote sensing
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Occurrence modes and comprehensive utilization of critical metal resources associated with coal:A review
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作者 Qin Zhang Wei Cheng +6 位作者 Tiebin Zhang Hongbo Liu Jiwei Yuan Aoao Chen Tingshun Wang Qian Liu Jianghe Wang 《International Journal of Mining Science and Technology》 2026年第2期277-293,共17页
Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a syste... Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a systematic review of the enrichment characteristics,occurrence modes,and comprehensive utilization potential of these critical metals in coal.Globally,the distribution of these metal resources exhibits significant regional heterogeneity.While the concentration in most coals falls below industrial cut-off grades,anomalous enrichment in specific coal basins results in Li,Ga,Ge,and REE concentrations far exceeding global averages,highlighting their considerable potential as unconventional metal deposits.The occurrence modes of these metals are diverse:Li is primarily hosted in mineral phases;Ga exists in inorganic,organic,and complex forms;Ge shows a strong association with organic matter;and REE are mainly present in adsorbed/isomorphic forms within clay minerals,while also displaying organic affinity.Direct extraction of metals from raw coal is often cost-prohibitive;effective recovery is therefore more feasible when integrated with coal processing.Metals are further enriched in solid wastes such as coal gangue,fly ash,and bottom ash,from which recovery is more economically and technically viable.Current comprehensive utilization primarily employs integrated mineral processing-hydrometallurgy approaches.Future research should focus on elucidating the precise occurrence forms of metals in coal and solid wastes,optimizing pre-treatment methods,and selecting effective activators and leachants.Advancing the synergistic extraction and green recovery of multiple associated resources from coal and its by-products is essential for achieving high-value,comprehensive utilization of coal-based resources. 展开更多
关键词 Coal-associated resources Lithium GALLIUM GERMANIUM Rare carth elements Extraction and separation
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Pavement Crack Detection Based on Star-YOLO11
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作者 Jiang Mi Zhijian Gan +3 位作者 Pengliu Tan Xin Chang Zhi Wang Haisheng Xie 《Computers, Materials & Continua》 2026年第1期962-983,共22页
In response to the challenges in highway pavement distress detection,such as multiple defect categories,difficulties in feature extraction for different damage types,and slow identification speeds,this paper proposes ... In response to the challenges in highway pavement distress detection,such as multiple defect categories,difficulties in feature extraction for different damage types,and slow identification speeds,this paper proposes an enhanced pavement crack detection model named Star-YOLO11.This improved algorithm modifies the YOLO11 architecture by substituting the original C3k2 backbone network with a Star-s50 feature extraction network.The enhanced structure adjusts the number of stacked layers in the StarBlock module to optimize detection accuracy and improve model efficiency.To enhance the accuracy of pavement crack detection and improve model efficiency,three key modifications to the YOLO11 architecture are proposed.Firstly,the original C3k2 backbone is replaced with a StarBlock-based structure,forming the Star-s50 feature extraction backbone network.This lightweight redesign reduces computational complexity while maintaining detection precision.Secondly,to address the inefficiency of the original Partial Self-attention(PSA)mechanism in capturing localized crack features,the convolutional prior-aware Channel Prior Convolutional Attention(CPCA)mechanism is integrated into the channel dimension,creating a hybrid CPC-C2PSA attention structure.Thirdly,the original neck structure is upgraded to a Star Multi-Branch Auxiliary Feature Pyramid Network(SMAFPN)based on the Multi-Branch Auxiliary Feature Pyramid Network architecture,which adaptively fuses high-level semantic and low-level spatial information through Star-s50 connections and C3k2 extraction blocks.Additionally,a composite dataset augmentation strategy combining traditional and advanced augmentation techniques is developed.This strategy is validated on a specialized pavement dataset containing five distinct crack categories for comprehensive training and evaluation.Experimental results indicate that the proposed Star-YOLO11 achieves an accuracy of 89.9%(3.5%higher than the baseline),a mean average precision(mAP)of 90.3%(+2.6%),and an F1-score of 85.8%(+0.5%),while reducing the model size by 18.8%and reaching a frame rate of 225.73 frames per second(FPS)for real-time detection.It shows potential for lightweight deployment in pavement crack detection tasks. 展开更多
关键词 Crack detection YOLO11 feature extraction attention mechanism feature fusion
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